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Sample records for enamel caries lesions

  1. Assessment of enamel-dentin caries lesions detection using bitewing PSP digital images

    PubMed Central

    TORRES, Marianna Guanaes Gomes; SANTOS, Aline da Silva; NEVES, Frederico Sampaio; ARRIAGA, Marcel Lautenschlager; CAMPOS, Paulo Sérgio Flores; CRUSOÉ-REBELLO, Iêda

    2011-01-01

    Objectives The aim of this study was to evaluate the detection of enamel-dentin occlusal caries using photostimulable phosphor plates. Material and Methods The ability to detect enamel-dentin occlusal caries in 607 premolars and molars from 47 patients between 10 and 18 years old, referred to the School of Dentistry of the Federal University of Bahia, Brazil, was evaluated based on clinical and radiographic examinations, using the criteria proposed in a previous study. A total of 156 bitewing digital images were obtained using Digora® (Soredex Medical Systems, Helsinki, Finland) phosphor plates. The plates were scanned and the images were captured and displayed on a computer screen. Image evaluation was done using Digora® for Windows 2.1 software, Soredex®. The radiologists were allowed to use enhancement tools to obtain better visibility during scoring of the teeth based on the radiographic criteria proposed in a previous study. Descriptive analysis and chi-squared proportion tests were done at 5% significance level. Results The results of clinical examination showed a higher prevalence of teeth with a straight dark line or demineralization of the occlusal fissure (score 1) and a lower prevalence of sealed teeth (score 5). In the bitewing digital images, 47 teeth presented visible radiolucency, circumscribed, in dentin under occlusal enamel (enamel-dentin caries lesions). Conclusions Correlating the clinical and radiographic findings, it was found that in the majority of teeth diagnosed by radiographic images as having enamel-dentin caries, no caries could be detected by clinical examination. PMID:21986650

  2. Surface Roughness of Initial Enamel Caries Lesions in Human Teeth After Resin Infiltration

    PubMed Central

    Arnold, Wolfgang H.; Meyer, Ann-Kathrin; Naumova, Ella A.

    2016-01-01

    Background: Low viscosity resin infiltration of initial caries lesions is a modern microinvasive method to treat initial cries lesions. However, only scarce information is available about the long-term surface alterations of infiltrated lesions. Methods: Twenty-eight premolar teeth exhibiting non-cavitated initial caries lesions (International Caries Detection and Assessment System (ICDAS code 1&2)) were divided into two groups, one of which was infiltrated with resin, and the other remained untreated. The teeth underwent two thermocycling procedures. The surface roughness was determined quantitatively, and the results were evaluated statistically. In addition, the surfaces of the lesions were investigated by scanning electron microscopy (SEM), and the surface was analyzed visually with respect to surface irregularities. Results: The results showed a reduction in the surface roughness that was significant after 2500 thermocycles compared to the untreated surface. In the control specimens, no change in the surface roughness was found. The qualitative SEM data also showed a smooth surface after thermocycling, which supported the statistical findings. Conclusion: After thermocycling, resin-infiltrated enamel surfaces become smoother and had no additional risk for plaque accumulation. PMID:27733877

  3. Remineralizing efficacy of a CPP-ACP cream on enamel caries lesions in situ.

    PubMed

    Meyer-Lueckel, Hendrik; Wierichs, Richard J; Schellwien, Timo; Paris, Sebastian

    2015-01-01

    The aim of this double-blind, randomized, cross-over in situ study was to compare the remineralizing effects induced by the application of casein phosphopeptide-stabilized amorphous calcium phosphate complexes (CPP-ACP)-containing cream (without fluoride) after the use of fluoride toothpaste with the prolonged use of fluoride toothpaste on enamel caries lesions in situ. During each of three experimental legs of 4 weeks, 13 participants wore intra-oral mandibular appliances with 8 pre-demineralized bovine enamel specimens in the vestibular flanges mimicking either 'easily cleanable' or 'proximal' surfaces (n = 312). The three randomly allocated treatments were as follows: (1) application of CPP-ACP-containing cream (GC Tooth Mouse, non-fluoride) after the use of fluoride toothpaste (1,400 ppm NaF; TM), (2) prolonged application of fluoride toothpaste (1,400 ppm NaF; positive control, PC) and (3) prolonged application of fluoride-free toothpaste (negative control, NC). Additionally, one of each of the two flanges was brushed twice daily with the respective toothpaste. The differences in integrated mineral loss as assessed by transversal microradiography were calculated between values before and after the in situ period. Changes in mineral loss were analysed for those pairs of subgroups differing in only one of the three factors (intervention, brushing and position). The PC treatment induced a significantly higher mineral gain compared with the TM and NC treatments. No significant differences between TM and NC for both positions were observed. In conclusion, the additional use of a CPP-ACP-containing cream seems to be less efficacious in remineralizing caries lesions than the prolonged application of fluoride toothpaste.

  4. Role of Candida species from HIV infected children in enamel caries lesions: an in vitro study

    PubMed Central

    CHARONE, Senda; PORTELA, Maristela Barbosa; MARTINS, Karol de Oliveira; SOARES, Rosangela Maria; CASTRO, Gloria Fernanda

    2017-01-01

    Abstract Objectives This study analyzed the capacity of Candida spp. from dental biofilm of HIV infected (HIV+) children to demineralize primary molar enamel in vitro by Transversal Microhardness (TMH), Polarized Light Microscopy (PLM) and the quantity of calcium ions (Ca2+) released from the enamel. Material and Methods Candida spp. samples were isolated from the supragingival biofilm of HIV+ children. A hundred and forty (140) enamel blocks were randomly assigned to six groups: biofilm formed by C. albicans (Group 1); mixed biofilm formed by C. albicans and C. tropicalis (Group 2); mixed biofilm formed by C. albicans and C. parapsilosis (Group 3); mixed biofilm formed by C. albicans, C. parapsilosis and C. glabrata (Group 4); biofilm formed by C. albicans ATCC (Group 5) and medium without Candida (Group 6). Enamel blocks from each group were removed on days 3, 5, 8 and 15 after biofilm formation to evaluate the TMH and images of enamel were analyzed by PLM. The quantity of Ca2+ released, from Groups 1 and 6, was determined using an Atomic Absorption Spectrophotometer. The SPSS program was used for statistical analysis and the significance level was 5%. Results TMH showed a gradual reduction in enamel hardness (p<0.05) from the 1st to 15th day, but mainly five days after biofilm formation in all groups. The PLM showed superficial lesions indicating an increase in porosity. C. albicans caused the release of Ca2+ into suspension during biofilm formation. Conclusion Candida species from dental biofilm of HIV+ children can cause demineralization of primary enamel in vitro. PMID:28198976

  5. In vitro re-hardening of artificial enamel caries lesions using enamel matrix proteins or self-assembling peptides

    PubMed Central

    Schmidlin, Patrick; Zobrist, Katja; Attin, Thomas; Wegehaupt, Florian

    2016-01-01

    ABSTRACT Objectives To assess the re-hardening potential of enamel matrix derivatives (EMD) and self-assembling peptides in vitro, hypothesizing that these materials may increase the mineralization of artificial carious lesions and improve hardness profiles. Material and Methods Forty-eight enamel samples were prepared from extracted bovine lower central incisors. After embedding and polishing, nail varnish was applied, leaving a defined test area. One third of this area was covered with a flowable composite (non-demineralized control). The remaining area was demineralized in an acidic buffer solution for 18 d to simulate a carious lesion. Half the demineralized area was then covered with composite (demineralized control), while the last third was left open for three test and one control treatments: (A) Application of enamel-matrix proteins (EMD - lyophilized protein fractions dissolved in acetic acid, Straumann), (B) self-assembling peptides (SAP, Curodont), or (C) amine fluoride solution (Am-F, GABA) for 5 min each. Untreated samples (D) served as control. After treatment, samples were immersed in artificial saliva for four weeks (remineralization phase) and microhardness (Knoop) depth profiles (25-300 µm) were obtained at sections. Two-way ANOVA was calculated to determine differences between the areas (re-hardening or softening). Results Decalcification resulted in significant softening of the subsurface enamel in all groups (A-D). A significant re-hardening up to 125 µm was observed in the EMD and SAP groups. Conclusions This study showed that EMD and SAP were able to improve the hardness profiles when applied to deep demineralized artificial lesions. However, further research is needed to verify and improve this observed effect. PMID:27008255

  6. Lasers effects on enamel for caries prevention

    NASA Astrophysics Data System (ADS)

    Ana, P. A.; Bachmann, L.; Zezell, D. M.

    2006-05-01

    The aim of this study was to ascertain whether laser irradiation is able to reduce caries incidence. For this purpose, the effects of laser on enamel and on fluoride uptake were discussed. Current literature regarding the preventive effect of laser irradiation on dental hard tissue has been reviewed. An evaluation of the results of the available in vitro and in vivo studies on the efficacy of anticaries and induced changes on enamel by laser irradiation were also performed. Articles were selected using the Medline, Web of Science, Embase, and Cochrane databases, and the results of these studies were described. The most common lasers employed for caries prevention on enamel are Nd:YAG; CO2; Er:YAG; Er,Cr:YSGG; and argon. The percentage of inhibition of dental caries varied from 30 to 97.2%, and the association with fluoride has demonstrated the best results on inhibition of caries development. Laser irradiation under specific conditions can change the crystallographic properties of apatite crystals, increasing the acid resistance of lased enamel. The combined treatment of laser irradiation with fluoride propitiates an expressive fluoride uptake, reducing the progression of carieslike lesions, and this treatment is more effective than laser or fluoride alone. Available data suggest that lasers combined with fluoride is a promising treatment in caries prevention.

  7. CO2 Laser and Topical Fluoride Therapy in the Control of Caries Lesions on Demineralized Primary Enamel

    PubMed Central

    Valério, R. A.; Saraiva, M. C. P.; Corona, S. A. M.

    2015-01-01

    This study evaluated the effect of CO2 laser irradiation and topical fluoride therapy in the control of caries progression on primary teeth enamel. 30 fragments (3 × 3 × 2 mm) from primary canines were submitted to an initial cariogenic challenge that consisted of immersion on demineralizing solution for 3 hours and remineralizing solution for 21 hours for 5 days. Fragments were randomly assigned into three groups (n = 10): L: CO2 laser (λ = 10.6 μm), APF: 1.23% acidulated phosphate fluoride, and C: no treatment (control). CO2 laser was applied with 0.5 W power and 0.44 J/cm2 energy density. Fluoride application was performed with 0.1 g for 1 minute. Cariogenic challenge was conducted for 5 days following protocol previously described. Subsurface Knoop microhardness was measured at 30 μm from the edge. Obtained data were subjected to analysis the variance (ANOVA) and Duncan test with significance of 5%. It was found that the L group showed greater control of deciduous enamel demineralization and were similar to those of APF group, while being statistically different from C group (P ≤ 0.05) that showed the lowest microhardness values. It was concluded that CO2 laser can be an additional resource in caries control progression on primary teeth enamel. PMID:25874248

  8. CO2 laser and topical fluoride therapy in the control of caries lesions on demineralized primary enamel.

    PubMed

    Valério, R A; Rocha, C T; Galo, R; Borsatto, M C; Saraiva, M C P; Corona, S A M

    2015-01-01

    This study evaluated the effect of CO2 laser irradiation and topical fluoride therapy in the control of caries progression on primary teeth enamel. 30 fragments (3 × 3 × 2 mm) from primary canines were submitted to an initial cariogenic challenge that consisted of immersion on demineralizing solution for 3 hours and remineralizing solution for 21 hours for 5 days. Fragments were randomly assigned into three groups (n = 10): L: CO2 laser (λ = 10.6 μm), APF: 1.23% acidulated phosphate fluoride, and C: no treatment (control). CO2 laser was applied with 0.5 W power and 0.44 J/cm(2) energy density. Fluoride application was performed with 0.1 g for 1 minute. Cariogenic challenge was conducted for 5 days following protocol previously described. Subsurface Knoop microhardness was measured at 30 μm from the edge. Obtained data were subjected to analysis the variance (ANOVA) and Duncan test with significance of 5%. It was found that the L group showed greater control of deciduous enamel demineralization and were similar to those of APF group, while being statistically different from C group (P ≤ 0.05) that showed the lowest microhardness values. It was concluded that CO2 laser can be an additional resource in caries control progression on primary teeth enamel.

  9. The chemistry of enamel caries.

    PubMed

    Robinson, C; Shore, R C; Brookes, S J; Strafford, S; Wood, S R; Kirkham, J

    2000-01-01

    The chemical changes which occur during the process of carious destruction of enamel are complex due to a number of factors. First, substituted hydroxyapatite, the main component of dental enamel, can behave in a very complex manner during dissolution. This is due not only to its ability to accept substituent ions but also to the wide range of calcium phosphate species which can form following dissolution. In addition, the composition, i.e., the extent of substitution, changes throughout enamel in the direction of carious attack, i.e., from surface to interior. Both surface and positively birefringent zones of the lesion clearly illustrate that carious destruction is not simple dissolution. Selective dissolution of soluble minerals occurs, and there is the probability of reprecipitation. The role of fluoride here is crucial in that not only does it protect enamel per se but also its presence in solution means that rather insoluble fluoridated species can form very easily, encouraging redeposition. The role of organic material clearly needs further investigation, but there is the real possibility of both inhibition of repair and facilitation of redeposition. For the future, delivering fluoride deep into the lesion would appear to offer the prospect of improved repair. This would entail a delivery vehicle which solved the problem of fluoride uptake by apatite at the tooth surface. Elucidation of the role of organic material may also reveal putative mechanisms for encouraging repair and/or protecting the enamel mineral.

  10. Remineralization of initial enamel caries in vitro using a novel peptide based on amelogenin

    NASA Astrophysics Data System (ADS)

    Li, Danxue; Lv, Xueping; Tu, Huanxin; Zhou, Xuedong; Yu, Haiyang; Zhang, Linglin

    2015-09-01

    Dental caries is the most common oral disease with high incidence, widely spread and can seriously affect the health of oral cavity and the whole body. Current caries prevention measures such as fluoride treatment, antimicrobial agents, and traditional Chinese herbal, have limitations to some extent. Here we design and synthesize a novel peptide based on the amelogenin, and assess its ability to promote the remineralization of initial enamel caries lesions. We used enamel blocks to form initial lesions, and then subjected to 12-day pH cycling in the presence of peptide, NaF and HEPES buffer. Enamel treated with peptide or NaF had shallower, narrower lesions, thicker remineralized surfaces and less mineral loss than enamel treated with HEPES. This peptide can promote the remineralization of initial enamel caries and inhibit the progress of caries. It is a promising anti-caries agent with various research prospects and practical application value.

  11. EDX-Element Analysis of the In Vitro Effect of Fluoride Oral Hygiene Tablets on Artificial Caries Lesion Formation and Remineralization in Human Enamel.

    PubMed

    Eggerath, J; Kremniczky, T; Gaengler, P; Arnold, W H

    2011-01-01

    Aim of this in-vitro-study was to assess the remineralization potential of a tooth cleaning tablet with different fluoride content quantitatively using EDX analysis.Twenty three caries free impacted third molars were examined; enamel surfaces were wax coated leaving two 3x4mm windows for exposure to demineralization/remineralization cycles. The teeth were randomly assigned to 4 groups of 5 control and 6 experimental teeth each. Demineralization by standardized HEC-gel, pH 4.7 at 37°C for 72h, was alternated by rinsing in remineralization solution, pH 7.0 at 37°C for 72h, total challenge time 432h. The negative control group N was treated during remineralization cycles with saline; positive control group P was treated with remineralization solution; experimental group D1 was exposed to remineralization solution containing Denttabs(®)-tablets with 1450 ppm F; experimental group D2 was exposed to remineralization solution and Denttabs(®)-tablets with 4350 ppm F. Each tooth was cut into serial sections and analyzed by scanning electron microscopy with EDX element analysis for assessment of the different zones of the lesions in 3 representative sections. Statistical analysis was based on the AVOVA test for repeated measurements and post hoc Bonferroni adjustment. The results showed a significantly higher Ca and P content in the body of the lesion in both fluoride treated groups compared to the controls. It can be concluded that higher concentrations of NaF may be more effective in remineralization of early advanced caries lesions.

  12. Remineralization of caries lesions extending into dentin.

    PubMed

    ten Cate, J M

    2001-05-01

    Remineralization is one aspect of the overall process of tooth decay. However, it is primarily studied in shallow lesions. The aim of this study was to explore whether caries lesions in enamel and extending into the dentin can be remineralized. A single-section model was developed for the longitudinal and non-destructive monitoring of changes in enamel and dentin. Lesions at least 200 microm into dentin were formed in undersaturated acetate buffers. Next, the lesions were divided into groups (three treatment and one control) and remineralized. The treatments were: weekly immersion in 1,000 ppm fluoride, single treatment with methanehydroxybisphosphonate, and a constant level of 1 ppm fluoride. De- and remineralization was assessed by transverse microradiography. Remineralization was observed in enamel, but also in dentin, indicating that, deep into dentin, the pores become supersaturated to apatite formation. Treatments affected remineralization only in the outer part of enamel. Both findings are explained by a relatively fast diffusion of mineral ions, with precipitation being rate-limiting. The results suggest that dentin remineralization, underneath enamel, can be achieved and could possibly be used in clinical treatment strategies.

  13. Genetic influences on dental enamel that impact caries differ between the primary and permanent dentitions

    PubMed Central

    Bayram, Merve; Deeley, Kathleen; Reis, Maria Fernanda; Trombetta, Vanessa M.; Ruff, Timothy D.; Sencak, Regina C.; Hummel, Michael; Dizak, Piper M.; Washam, Kelly; Romanos, Helena F.; Lips, Helena F.; Alves, Gutemberg; Costa, Marcelo C.; Granjeiro, José M.; Antunes, Leonardo S.; Küchler, Erika C.; Seymen, Figen; Vieira, Alexandre R.

    2015-01-01

    Clinically, primary and permanent teeth are distinct anatomically and the presentation of caries lesions differs between the two dentitions. However, the possibility exists that genetic contributions to tooth formation of the two dentitions are different. The purpose of this study was to test the hypothesis that genetic associations with an artificial caries model will not be the same between primary and permanent dentitions. Enamel samples from primary and permanent teeth were tested for microhardness at baseline, after carious lesion creation, and after fluoride application to verify association with genetic variants of selected genes. Associations were found between genetic variants of ameloblastin, amelogenin, enamelin, tuftelin, tuftelin interactive protein 11, and matrix metalloproteinase 20 and enamel from permanent teeth but not with enamel from primary teeth. In conclusion, our data continue to support that genetic variation may impact enamel development and consequently individual caries susceptibility. These effects may be distinct between primary and permanent dentitions. PMID:26283008

  14. Impact of enamel defects on early caries development in preschool children.

    PubMed

    Carvalho, J C; Silva, E F; Gomes, R R; Fonseca, J A C; Mestrinho, H D

    2011-01-01

    Quantitative defects of the enamel are considered risk factors for caries development at the cavitated level. Since caries risk assessment and control should be implemented as early as possible in order to prevent operative treatment, it seemed interesting to investigate the relationship between enamel defects and caries development in the stages of progression that precede cavitation. The impact of enamel defects and selected child-mother indicators on early caries development was investigated in a cohort of Brazilian preschool children. The null hypothesis that developmental defects of the enamel and dental caries are independent and that an association between them occurs by chance was tested. The sample (n = 1,718) was made up of 2- to 5-year-olds. Developmental defects of enamel and caries on buccal surfaces were identified in 48 and 26% of the children, respectively. Bivariate analyses at the surface level showed neither an association between demarcated/diffuse opacity and caries experience (p ≥ 0.64, GLM), nor between the presence of hypoplastic surfaces and non-cavitated lesions (p = 0.29, GLM). The multivariate analyses indicated that in the mouths of individual children, hypoplastic surfaces were more likely to present filled surfaces and non-cavitated/cavitated lesions than non-hypoplastic surfaces (within-child p = 0.03, GEE). However, children having teeth with hypoplastic surfaces were not at higher caries risk than those children who did not present hypoplastic surfaces (between-child p = 0.23, GEE). The null hypothesis could not be accepted for quantitative defects such as hypoplasia, since they had a significant impact on the within-child prevalence of filled surfaces and non-cavitated/cavitated lesions.

  15. Metatranscriptomics reveals overall active bacterial composition in caries lesions

    PubMed Central

    Simón-Soro, Aurea; Guillen-Navarro, Miriam; Mira, Alex

    2014-01-01

    Background Identifying the microbial species in caries lesions is instrumental to determine the etiology of dental caries. However, a significant proportion of bacteria in carious lesions have not been cultured, and the use of molecular methods has been limited to DNA-based approaches, which detect both active and inactive or dead microorganisms. Objective To identify the RNA-based, metabolically active bacterial composition of caries lesions at different stages of disease progression in order to provide a list of potential etiological agents of tooth decay. Design Non-cavitated enamel caries lesions (n=15) and dentin caries lesions samples (n=12) were collected from 13 individuals. RNA was extracted and cDNA was constructed, which was used to amplify the 16S rRNA gene. The resulting 780 bp polymerase chain reaction products were pyrosequenced using Titanium-plus chemistry, and the sequences obtained were used to determine the bacterial composition. Results A mean of 4,900 sequences of the 16S rRNA gene with an average read length of 661 bp was obtained per sample, giving a comprehensive view of the active bacterial communities in caries lesions. Estimates of bacterial diversity indicate that the microbiota of cavities is highly complex, each sample containing between 70 and 400 metabolically active species. The composition of these bacterial consortia varied among individuals and between caries lesions of the same individuals. In addition, enamel and dentin lesions had a different bacterial makeup. Lactobacilli were found almost exclusively in dentin cavities. Streptococci accounted for 40% of the total active community in enamel caries, and 20% in dentin caries. However, Streptococcus mutans represented only 0.02–0.73% of the total bacterial community. Conclusions The data indicate that the etiology of dental caries is tissue dependent and that the disease has a clear polymicrobial origin. The low proportion of mutans streptococci detected confirms that they

  16. Sugar Alcohols, Caries Incidence, and Remineralization of Caries Lesions: A Literature Review

    PubMed Central

    Mäkinen, Kauko K.

    2010-01-01

    Remineralization of minor enamel defects is a normal physiological process that is well known to clinicians and researchers in dentistry and oral biology. This process can be facilitated by various dietary and oral hygiene procedures and may also concern dentin caries lesions. Dental caries is reversible if detected and treated sufficiently early. Habitual use of xylitol, a sugar alcohol of the pentitol type, can be associated with significant reduction in caries incidence and with tooth remineralization. Other dietary polyols that can remarkably lower the incidence of caries include erythritol which is a tetritol-type alditol. Based on known molecular parameters of simple dietary alditols, it is conceivable to predict that their efficacy in caries prevention will follow the homologous series, that is, that the number of OH-groups present in the alditol molecule will determine the efficacy as follows: erythritol ≥ xylitol > sorbitol. The possible difference between erythritol and xylitol must be confirmed in future clinical trials. PMID:20339492

  17. Pulsed Nd:YAG laser selective ablation of surface enamel caries: II. Histology and clinical trials

    NASA Astrophysics Data System (ADS)

    Harris, David M.; Goodis, Harold E.; White, Joel M.; Arcoria, Charles J.; Simon, James; Burkart, John; Yessik, Michael J.; Myers, Terry D.

    2000-03-01

    High intensity infrared light from the pulsed Nd:YAG dental laser is absorbed by pigmented carious enamel and not absorbed by normal enamel. Therefore, this system is capable of selective removal of surface enamel caries. Safety and efficacy of the clinical procedure was evaluated in two sets of clinical trials at three dental schools. Carious lesions were randomized to drill or laser treatment. Pulp vitality, surface condition, preparations and restorations were evaluated by blinded evaluators. In Study 1 surface caries were removed from 104 third molars scheduled for extraction. One week post-treatment teeth were extracted and the pulp was examined histologically. In Study 2 90 patients with 422 lesions on 376 teeth were randomized to laser or drill and followed for six months. There were no adverse events and both clinical and histological evaluations of pulp vitality showed no abnormalities. Caries were removed in all conditions. A significantly greater number of preparations in the drill groups vs. laser groups entered dentin (drill equals 11, laser equals 1, p less than 0.001). This indicates that the more conservative laser treatment removed the caries but not the sound enamel below the lesion.

  18. In Vitro Acid-Mediated Initial Dental Enamel Loss Is Associated with Genetic Variants Previously Linked to Caries Experience.

    PubMed

    Vieira, Alexandre R; Bayram, Merve; Seymen, Figen; Sencak, Regina C; Lippert, Frank; Modesto, Adriana

    2017-01-01

    We have previously shown that AQP5 and BTF3 genetic variation and expression in whole saliva are associated with caries experience suggesting that these genes may have a functional role in protecting against caries. To further explore these results, we tested ex vivo if variants in these genes are associated with subclinical dental enamel mineral loss. DNA and enamel samples were obtained from 53 individuals. Enamel samples were analyzed for Knoop hardness of sound enamel, integrated mineral loss after subclinical carious lesion creation, and change in integrated mineral loss after remineralization. DNA samples were genotyped for single nucleotide polymorphisms using TaqMan chemistry. Chi-square and Fisher's exact tests were used to compare individuals above and below the mean sound enamel microhardness of the cohort with alpha of 0.05. The A allele of BTF3 rs6862039 appears to be associated with harder enamel at baseline (p = 0.09), enamel more resistant to demineralization (p = 0.01), and enamel that more efficiently regain mineral and remineralize (p = 0.04). Similarly, the G allele of AQP5 marker rs3759129 and A allele of AQP5 marker rs296763 are associated with enamel more resistant to demineralization (p = 0.03 and 0.05, respectively). AQP5 and BTF3 genetic variations influence the initial subclinical stages of caries lesion formation in the subsurface of enamel.

  19. In Vitro Acid-Mediated Initial Dental Enamel Loss Is Associated with Genetic Variants Previously Linked to Caries Experience

    PubMed Central

    Vieira, Alexandre R.; Bayram, Merve; Seymen, Figen; Sencak, Regina C.; Lippert, Frank; Modesto, Adriana

    2017-01-01

    We have previously shown that AQP5 and BTF3 genetic variation and expression in whole saliva are associated with caries experience suggesting that these genes may have a functional role in protecting against caries. To further explore these results, we tested ex vivo if variants in these genes are associated with subclinical dental enamel mineral loss. DNA and enamel samples were obtained from 53 individuals. Enamel samples were analyzed for Knoop hardness of sound enamel, integrated mineral loss after subclinical carious lesion creation, and change in integrated mineral loss after remineralization. DNA samples were genotyped for single nucleotide polymorphisms using TaqMan chemistry. Chi-square and Fisher's exact tests were used to compare individuals above and below the mean sound enamel microhardness of the cohort with alpha of 0.05. The A allele of BTF3 rs6862039 appears to be associated with harder enamel at baseline (p = 0.09), enamel more resistant to demineralization (p = 0.01), and enamel that more efficiently regain mineral and remineralize (p = 0.04). Similarly, the G allele of AQP5 marker rs3759129 and A allele of AQP5 marker rs296763 are associated with enamel more resistant to demineralization (p = 0.03 and 0.05, respectively). AQP5 and BTF3 genetic variations influence the initial subclinical stages of caries lesion formation in the subsurface of enamel. PMID:28275354

  20. Imaging simulated secondary caries lesions with cross polarization OCT

    NASA Astrophysics Data System (ADS)

    Stahl, Jonathan; Kang, Hobin; Fried, Daniel

    2010-02-01

    The clinical diagnosis of secondary caries has been found to account for the replacement of the majority of intra-coronal restorations. Current methods to diagnose the presence of these lesions at early stages are considered insufficient due to their low sensitivity. Polarization-sensitive optical coherence tomography (PS-OCT) imaging studies have confirmed its effectiveness for imaging carious subsurface lesions in enamel and dentin. The objective of this study was to determine if PS-OCT can be used to nondestructively image demineralization through resin restorations on extracted teeth with both simulated and natural lesions. Simulated secondary caries lesions were created by exposing cavity preparations made in extracted human teeth to a demineralizing solution for 48 hours and subsequently restoring with resin. Negative control restorations were also prepared on each tooth. Optical changes in demineralized versus control preparations beneath restorations were measured as a function of depth using PS-OCT. PS-OCT images indicated that a significant increase in reflectivity and depth occurred in the simulated lesions compared with the control preparations. This study suggests that PS-OCT is well-suited to nondestructively detect early caries lesions in enamel beneath composite restorations.

  1. Dentifrice fluoride and abrasivity interplay on artificial caries lesions.

    PubMed

    Nassar, Hani M; Lippert, Frank; Eckert, George J; Hara, Anderson T

    2014-01-01

    Incipient caries lesions on smooth surfaces may be subjected to toothbrushing, potentially leading to remineralization and/or abrasive wear. The interplay of dentifrice abrasivity and fluoride on this process is largely unknown and was investigated on three artificially created lesions with different mineral content/distribution. 120 bovine enamel specimens were randomly allocated to 12 groups (n = 10), resulting from the association of (1) lesion type [methylcellulose acid gel (MeC); carboxymethylcellulose solution (CMC); hydroxyethylcellulose gel (HEC)], (2) slurry abrasive level [low (REA 4/ RDA 69); high (REA 7/RDA 208)], and (3) fluoride concentration [0/275 ppm (14.5 mM) F as NaF]. After lesion creation, specimens were brushed in an automated brushing machine with the test slurries (50 strokes 2×/day). Specimens were kept in artificial saliva in between brushings and overnight. Enamel surface loss (SL) was determined by optical profilometry after lesion creation, 1, 3 and 5 days. Two enamel sections (from baseline and post-brushing areas) were obtained and analyzed microradiographically. Data were analyzed by analysis of variance and Tukey's tests (α = 5%). Brushing with high-abrasive slurry caused more SL than brushing with low-abrasive slurry. For MeC and CMC lesions, fluoride had a protective effect on SL from day 3 on. Furthermore, for MeC and CMC, there was a significant mineral gain in the remaining lesions except when brushed with high-abrasive slurries and 0 ppm F. For HEC, a significant mineral gain took place when low-abrasive slurry was used with fluoride. The tested lesions responded differently to the toothbrushing procedures. Both slurry fluoride content and abrasivity directly impacted SL and mineral gain of enamel caries lesions.

  2. Optical Assessment of Caries Lesion Structure and Activity

    NASA Astrophysics Data System (ADS)

    Lee, Robert Chulsung

    New, more sophisticated diagnostic tools are needed for the detection and characterization of caries lesions in the early stages of development. It is not sufficient to simply detect caries lesions, methods are needed to assess the activity of the lesion and determine if chemical or surgical intervention is needed. Previous studies have demonstrated that polarization sensitive optical coherence tomography (PS-OCT) can be used to nondestructively image the subsurface lesion structure and measure the thickness of the highly mineralized surface zone. Other studies have demonstrated that the rate of dehydration can be correlated with the lesion activity and that the rate can be measured using optical methods. The main objective of this work was to test the hypothesis that optical methods can be used to assess lesion activity on tooth coronal and root surfaces. Simulated caries models were used to develop and validate an algorithm for detecting and measuring the highly mineralized surface layer using PS-OCT. This work confirmed that the algorithm was capable of estimating the thickness of the highly mineralized surface layer with high accuracy. Near-infrared (NIR) reflectance and thermal imaging methods were used to assess activity of caries lesions by measuring the state of lesion hydration. NIR reflectance imaging performed the best for artificial enamel and natural coronal caries lesion samples, particularly at wavelengths coincident with the water absorption band at 1460-nm. However, thermal imaging performed the best for artificial dentin and natural root caries lesion samples. These novel optical methods outperformed the conventional methods (ICDAS II) in accurately assessing lesion activity of natural coronal and root caries lesions. Infrared-based imaging methods have shown potential for in-vivo applications to objectively assess caries lesion activity in a single examination. It is likely that if future clinical trials are a success, this novel imaging

  3. Contact versus non-contact ablation of the artificial enamel caries by Er:YAG and CTH:YAG laser radiation

    NASA Astrophysics Data System (ADS)

    Dostálová, Tat'jana; Jelínková, Helena; Å ulc, Jan; Němec, Michal; Bučková, Michaela; Kašparová, Magdalena; Miyagi, Mitsunobu

    The aim of study is to compare the ablation effect of contact and non-contact interaction of Er:YAG and CTH:YAG laser radiation with artificial enamel caries lesion. The artificial caries was prepared in intact teeth to simulate demineralized surface and the laser radiation was applied. Contact and non-contact ablation was compared. Two laser systems Er:YAG 2.94 μm and CTH:YAG 2.1 μm were used. The enamel artificial caries were gently removed by laser radiation and flow Sonic fill composite resin was inserted. Scanning electron microscope was use to evaluate the enamel surface.

  4. The prevalence of caries and enamel defects in 229 Malaysian children 16 years after water fluoridation (a pilot study).

    PubMed

    Majid, Z A; Hussein, N N; Bagramian, R A

    1996-07-01

    Two hundred and twenty-nine children aged 12-15 years who were continuous residents of Penang island, in the north of Peninsular Malaysia were examined for caries and enamel defects. Caries prevalence was 82.2% with a DMFT score of 3.4 and DMFS score of 4.9; there were very few missing teeth and very little untreated caries in the population examined. Majority of DF (decayed/filled) lesions were pits and fissures with approximal and smooth surfaces relatively caries free. The prevalence of enamel defects was 76.4% with 19.1% of all teeth examined being affected. More posterior than anterior teeth were affected by enamel defects just as there were more maxillary than mandibular teeth affected by enamel defects. Diffuse patchy opacities were the most common defect diagnosed and this was found in 60.2% of the population examined. A bilateral distribution of diffuse patchy opacities was seen in 41.5% of the population examined. Tooth surfaces with enamel defects were no more susceptible to caries than defect-free surfaces.

  5. Quantitative evaluation of simulated human enamel caries kinetics using photothermal radiometry and modulated luminescence

    NASA Astrophysics Data System (ADS)

    Hellen, Adam; Mandelis, Andreas; Finer, Yoav; Amaechi, Bennett T.

    2011-03-01

    Photothermal radiometry and modulated luminescence (PTR-LUM) is a non-destructive methodology applied toward the detection, monitoring and quantification of dental caries. The purpose of this study was to evaluate the efficacy of PTRLUM to detect incipient caries lesions and quantify opto-thermophysical properties as a function of treatment time. Extracted human molars (n=15) were exposed to an acid demineralization gel (pH 4.5) for 10 or 40 days in order to simulate incipient caries lesions. PTR-LUM frequency scans (1 Hz - 1 kHz) were performed prior to and during demineralization. Transverse Micro-Radiography (TMR) analysis followed at treatment conclusion. A coupled diffusephoton- density-wave and thermal-wave theoretical model was applied to PTR experimental amplitude and phase data across the frequency range of 4 Hz - 354 Hz, to quantitatively evaluate changes in thermal and optical properties of sound and demineralized enamel. Excellent fits with small residuals were observed experimental and theoretical data illustrating the robustness of the computational algorithm. Increased scattering coefficients and poorer thermophysical properties were characteristic of demineralized lesion bodies. Enhanced optical scattering coefficients of demineralized lesions resulted in poorer luminescence yield due to scattering of both incident and converted luminescent photons. Differences in the rate of lesion progression for the 10-day and 40-day samples points to a continuum of surface and diffusion controlled mechanism of lesion formation. PTR-LUM sensitivity to changes in tooth mineralization coupled with opto-thermophysical property extraction illustrates the technique's potential for non-destructive quantification of enamel caries.

  6. Zinc in the mouth, its interactions with dental enamel and possible effects on caries; a review of the literature.

    PubMed

    Lynch, Richard J M

    2011-08-01

    Zinc is an essential trace element. In the mouth, it is present naturally in plaque, saliva and enamel. Zinc is formulated into oral health products to control plaque, reduce malodour and inhibit calculus formation. It has good oral substantivity, and elevated concentrations can persist for many hours in plaque and saliva following delivery from mouthrinses and toothpastes. Although low concentrations of zinc can both reduce enamel demineralisation and modify remineralisation, during caries clinical trials, the addition of zinc to fluoride toothpastes has not affected their ability to reduce caries. Mechanistic studies may help explain this apparent contradiction. Zinc is readily desorbed from hydroxyapatite by calcium, which is plentiful in plaque and saliva. Where crystal-growth sites remain occupied by zinc despite this, they may simply be 'over-grown' by remineralisation initiated at unoccupied sites. Further, under certain conditions, low concentrations of zinc can enhance remineralisation of enamel lesions, by retarding lesion arrestment. Although this may help to explain the apparent lack of an overall zinc effect on caries, it seems unlikely that any negative effects would be countered exactly by positive effects. Further mechanistic studies, complementing well-designed in vitro and in situ caries studies, should lead to further understanding of the zinc-enamel interactions relevant to demineralisation and remineralisation.

  7. Approximal secondary caries lesion progression, a 20-week in situ study.

    PubMed

    Thomas, R Z; Ruben, J L; ten Bosch, J J; Fidler, V; Huysmans, M C D N J M

    2007-01-01

    There is no consensus about the definition and progression of outer and wall lesions in secondary caries. In this study we investigated whether lesion progression is influenced by an adjacent composite restoration and whether wall lesions develop at the composite-tooth interface. In order to study the appearance and progression of approximal primary caries lesions and lesions next to composite restorations, 16 samples were placed in a full denture of each of 8 subjects. Each denture housed 4 restored and 4 unrestored enamel samples and similarly 8 dentin samples. All samples were distributed over 2 sample holders, in each of which 4 approximal spaces were simulated. Every 4 weeks the sample holders were microradiographed using transversal wavelength independent microradiography and lesion depth was measured. At the end of the study, after 20 weeks, the lesion depth of the outer lesions was 0-350 microm for enamel and 0-750 microm for dentin. The estimated difference in progression between secondary and primary lesions (1.1 microm/4 weeks, 95% CI: -9.2 to 11.4 microm) was not statistically significant (p = 0.83). Secondary outer lesions appeared and progressed as primary caries lesions. No clear wall lesions were found next to composite, but they were observed next to acrylic resin.

  8. Predictive research methods of enamel and dentine for initial caries detection

    PubMed Central

    2013-01-01

    Currently, various research methods of enamel and dentine for precautionary diagnostics of initial caries forms are developed; however, the vast majority of these do not provide objective criteria of caries diagnostics or are very difficult to perform. Therefore, the search of diagnostics and enamel research methods, which will allow predicting caries emergence and to carry out personalised prevention of this pathology, is necessary. In this review, modern diagnostic methods that allow understanding the main aspects of caries process, assess the risk of its development, and also suggest the possibility of emergency prevention of caries progression in the nearest future are presented. PMID:23800183

  9. The efficiency of child formula dentifrices containing different calcium and phosphate compounds on artificial enamel caries

    PubMed Central

    Rirattanapong, Praphasri; Vongsavan, Kadkao; Saengsirinavin, Chavengkiat; Khumsub, Ploychompoo

    2016-01-01

    Objectives: Fluoride toothpaste has been extensively used to prevent dental caries. However, the risk of fluorosis is concerning, especially in young children. Calcium phosphate has been an effective remineralizing agent and is present in commercial dental products, with no risk of fluorosis to users. This in vitro study aimed to compare the effects of different calcium phosphate compounds and fluoride-containing dentifrices on artificial caries in primary teeth. Materials and Methods: Fifty sound primary incisors were coated with nail varnish, leaving two 1 mm2 windows on the labial surface before immersion in demineralizing solution for 96 hours to produce artificial enamel lesions. Subsequently, one window from each tooth was coated with nail varnish, and all 50 teeth were divided into five groups (n = 10); group A – deionized water; group B – casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) paste (Tooth Mousse); group C – 500 ppm F (Colgate Spiderman®); group D – nonfluoridated toothpaste with triple calcium phosphate (Pureen®); and group E – tricalcium phosphate (TCP). Polarized light microscopy and Image-Pro® Plus software were used to evaluate lesions. Results: After a 7-day pH-cycle, mean lesion depths in groups A, B, C, D, and E had increased by 57.52 ± 10.66%, 33.28 ± 10.16%, 17.04 ± 4.76%, 32.51 ± 8.99%, and 21.76 ± 8.15%, respectively. All data were processed by the Statistical Package for the Social Sciences (version 16.0) software package. Comparison of percentage changes using one-way analysis of variance and Fisher's least squares difference tests at a 95% level of confidence demonstrated that group A was significantly different from the other groups (P < 0.001). Lesions in groups B and D had a significant lesion progression when compared with groups C and E. Conclusions: All toothpastes in this study had the potential to delay the demineralization progression of artificial enamel caries in primary teeth. The

  10. Isolated development of inner (wall) caries like lesions in a bacterial-based in vitro model.

    PubMed

    Diercke, K; Lussi, A; Kersten, T; Seemann, R

    2009-12-01

    The study conducted in a bacterial-based in vitro caries model aimed to determine whether typical inner secondary caries lesions can be detected at cavity walls of restorations with selected gap widths when the development of outer lesions is inhibited. Sixty bovine tooth specimens were randomly assigned to the following groups: test group 50 (TG50; gap, 50 microm), test group 100 (TG100; gap, 100 microm), test group 250 (TG250; gap, 250 microm) and a control group (CG; gap, 250 microm). The outer tooth surface of the test group specimens was covered with an acid-resistant varnish to inhibit the development of an outer caries lesion. After incubation in the caries model, the area of demineralization at the cavity wall was determined by confocal laser scanning microscopy. All test group specimens demonstrated only wall lesions. The CG specimens developed outer and wall lesions. The TG250 specimens showed significantly less wall lesion area compared to the CG (p < 0.05). In the test groups, a statistically significant increase (p < 0.05) in lesion area could be detected in enamel between TG50 and TG250 and in dentine between TG50 and TG100. In conclusion, the inner wall lesions of secondary caries can develop without the presence of outer lesions and therefore can be regarded as an entity on their own. The extent of independently developed wall lesions increased with gap width in the present setting.

  11. Numerical modelling of tooth enamel subsurface lesion formation induced by dental plaque.

    PubMed

    Ilie, O; van Turnhout, A G; van Loosdrecht, M C M; Picioreanu, C

    2014-01-01

    Using a one-dimensional mathematical model that couples tooth demineralisation and remineralisation with metabolic processes occurring in the dental plaque, two mechanisms for subsurface lesion formation were evaluated. It was found that a subsurface lesion can develop only as the result of alternating periods of demineralisation (acid attack during sugar consumption) and remineralisation (resting period) in tooth enamel with uniform mineral composition. It was also shown that a minimum plaque thickness that can induce an enamel lesion exists. The subsurface lesion formation can also be explained by assuming the existence of a fluoride-containing layer at the tooth surface that decreases enamel solubility. A nearly constant thickness of the surface layer was obtained with both proposed mechanisms. Sensitivity analysis showed that surface layer formation is strongly dependent on the length of remineralisation and demineralisation cycles. The restoration period is very important and the numerical simulations support the observation that often consumption of sugars is a key factor in caries formation. The calculated profiles of mineral content in enamel are similar to those observed experimentally. Most probably, both studied mechanisms interact in vivo in the process of caries development, but the simplest explanation for subsurface lesion formation remains the alternation between demineralisation and remineralisation cycles without any pre-imposed gradients.

  12. Infiltration of natural caries lesions in relation to their activity status and acid pretreatment in vitro.

    PubMed

    Neuhaus, K W; Schlafer, S; Lussi, A; Nyvad, B

    2013-01-01

    This study aimed at testing how active and inactive enamel caries lesions differ by their degree of resin infiltration, and whether the choice of acid pretreatment plays a crucial role. Four examiners assessed 104 human molars and premolars with noncavitated enamel lesions and classified them as 'active' or 'inactive' using the Nyvad criteria. Forty-five teeth were included in this study after independent unanimous lesion activity assessment. Lesions were cut perpendicularly into 2 halves. Each half lesion was pretreated with either 15% hydrochloric acid or 35% phosphoric acid. The lesions were infiltrated after staining with rhodamine isothiocyanate. Thin sections of 100 µm were prepared and the specimens were bleached with 30% hydrogen peroxide. The specimens were then counterstained with sodium fluorescein, subjected to confocal laser scanning microscopy and analyzed quantitatively. Outcome parameters were maximum and average infiltration depths as well as relative penetration depths and areas. In active lesions no significant difference of percentage maximum penetration depth and percentage average penetration depth between lesions pretreated with hydrochloric or phosphoric acid could be observed. In inactive lesions, however, phosphoric acid pretreatment resulted in significantly lower penetration compared to hydrochloric acid pretreatment. Surface conditioning with hydrochloric acid led to similar infiltration results in active and inactive lesions. Moreover, inactive lesions showed greater variability in all assessed infiltration parameters than did active lesions. In conclusion, caries lesion activity and acid pretreatment both influenced the infiltration. The use of phosphoric acid to increase permeability of the surface layer of active lesions should be further explored.

  13. Effect of nano-hydroxyapatite concentration on remineralization of initial enamel lesion in vitro.

    PubMed

    Huang, S B; Gao, S S; Yu, H Y

    2009-06-01

    The purpose of the research was to determine the effect of nano-hydroxyapatite concentrations on initial enamel lesions under dynamic pH-cycling conditions. Initial enamel lesions were prepared in bovine enamel with an acidic buffer. NaF (positive control), deionized water (negative control) and four different concentrations of nano-hydroxyapatite (1%, 5%, 10% and 15% wt%) were selected as the treatment agents. Surface microhardness (SMH) measurements were performed before/after demineralization and after 3, 6, 9 and 12 days of application, and the percentage surface microhardness recovery (%SMHR) was calculated. The specimens were then examined by a scanning electron microscope. The %SMHR in nano-hydroxyapatite groups was significantly greater than that of negative control. When the concentration of nano-HA was under 10%, SMH and %SMHR increased with increasing nano-hydroxyapatite concentrations. There were no significant differences between the 10% and 15% groups at different time periods in the pH-cycling. The SEM analysis showed that nano-hydroxyapatite particles were regularly deposited on the cellular structure of the demineralized enamel surface, which appeared to form new surface layers. It was concluded that nano-hydroxyapatite had the potential to remineralize initial enamel lesions. A concentration of 10% nano-hydroxyapatite may be optimal for remineralization of early enamel caries.

  14. Remineralization of artificial dentinal caries lesions by biomimetically modified Mineral Trioxide Aggregate

    PubMed Central

    Qi, Yi-pin; Li, Nan; Niu, Li-na; Primus, Carolyn M.; Ling, Jun-Qi; Pashley, David H.; Tay, Franklin R.

    2011-01-01

    Fluoride-releasing restorative materials are available for remineralization of enamel and root caries. However, dentin remineralization is more difficult than enamel remineralization due to the paucity of apatite seed crystallites along the lesion surface for heterogeneous crystal growth. Extracellular matrix proteins play critical roles in controlling apatite nucleation/growth in collagenous tissues. This study examined the remineralization efficacy of mineral trioxide aggregate (MTA) in phosphate-containing simulated body fluid (SBF) by incorporating polyacrylic acid and sodium tripolyphosphate as biomimetic analogs of matrix proteins for remineralizing caries-like dentin. Artificial caries-like dentin lesions incubated in SBF were remineralized over a 6-week period using MTA or MTA containing biomimetic analogs in the absence or presence of dentin adhesive application. Lesion depths and integrated mineral loss were monitored with micro-computed tomography. Ultrastructure of baseline and remineralized lesions were examined by transmission electron microscopy. Dentin remineralization was best achieved using MTA containing biomimetic analogs regardless of whether an adhesive was applied; dentinal tubules within the remineralized dentin were occluded by apatite. It is concluded that the MTA version employed in the study may be doped with biomimetic analogs for remineralization of unbonded and bonded artificial caries-like lesions in the presence of SBF. PMID:22085925

  15. PIXE analysis of caries related trace elements in tooth enamel

    NASA Astrophysics Data System (ADS)

    Annegarn, H. J.; Jodaikin, A.; Cleaton-Jones, P. E.; Sellschop, J. P. F.; Madiba, C. C. P.; Bibby, D.

    1981-03-01

    PIXE analysis has been applied to a set of twenty human teeth to determine trace element concentration in enamel from areas susceptible to dental caries (mesial and distal contact points) and in areas less susceptible to the disease (buccal surfaces), with the aim of determining the possible roles of trace elements in the curious process. The samples were caries-free anterior incisors extracted for periodontal reasons from subjects 10-30 years of age. Prior to extraction of the sample teeth, a detailed dental history and examination was carried out in each individual. PIXE analysis, using a 3 MeV proton beam of 1 mm diameter, allowed the determination of Ca, Mn, Fe, Cu, Zn, Sr and Pb above detection limits. As demonstrated in this work, the enhanced sensitivity of PIXE analysis over electron microprobe analysis, and the capability of localised surface analysis compared with the pooled samples required for neutron activation analysis, makes it a powerful and useful technique in dental analysis.

  16. Association between developmental defects of enamel and dental caries in schoolchildren.

    PubMed

    Vargas-Ferreira, F; Zeng, J; Thomson, W M; Peres, M A; Demarco, F F

    2014-05-01

    Despite improvement, dental caries is still the main public oral health problem worldwide and the major cause of pain, tooth loss and chewing difficulties in children and adolescents; and it impacts negatively on oral health-related quality of life. A cross-sectional study of a multistage representative sample of 8-12-year-old Brazilian school children was carried out in order to investigate the association between enamel defects and dental caries. Children's mothers completed a questionnaire about socio-demographic and behavioural characteristics at home. Firth's bias reduced logistic regression models were undertaken to assess the association between the main exposure (enamel defects) and caries experience. The prevalence of any enamel defect was 64.0%; the prevalence of diffuse opacities, demarcated opacities and enamel hypoplasia was 35.0%, 29.5% and 3.7%, respectively. The prevalence of dental caries was 32.4%, with mean DMFT of 0.6 (SD, 1.2). Dental caries experience was more common among children who had enamel hypoplasia in their posterior teeth (OR=2.79; 95% CI: 1.05, 6.51) than among those with none. In anterior teeth, there was no association. Enamel hypoplasia appears to be an important risk factor for dental caries.

  17. Quantifying the remineralization of artificial caries lesions using PS-OCT

    NASA Astrophysics Data System (ADS)

    Jones, Robert S.; Fried, Daniel

    2006-02-01

    New optical imaging methods are needed to determine whether caries lesions (tooth decay) are active and progressing or have become remineralized and arrested and are no longer progressing. The objective of this study was to use Polarization Sensitive Optical Coherence Tomography (PS-OCT) to image the fluoride enhanced remineralization of artificial enamel lesions. Artificial lesions were created by an acetate buffer on smooth enamel surfaces and were exposed for 20 days to a 2 ppm fluoride containing remineralization solution. PS-OCT images revealed the presence of a low scattering surface zone after the artificial lesions were remineralized. These samples displayed intact nondepolarizing surface zones when analyzed with Polarized Light Microscopy (PLM). No statistical difference in lesion depth before and after remineralization was found with both PS-OCT and PLM. The remineralized lesions showed a significant decrease in the overall integrated reflectivity compared with the demineralized lesions. Digital Microradiography confirmed the increase in mineral volume of the remineralized surface zone. This study determined that PS-OCT can image the restoration of the surface zone enamel after fluoride-enhanced remineralization of artificial in vitro dental caries.

  18. Effect of 10% carbamide peroxide bleaching on sound and artificial enamel carious lesions.

    PubMed

    Pinto, Cristiane Franco; Paes Leme, Adriana Franco; Cavalli, Vanessa; Giannini, Marcelo

    2009-01-01

    This study evaluated the effect of 10% carbamide peroxide (CP) bleaching on Knoop surface microhardness (KHN) and morphology of sound enamel and enamel with early artificial caries lesions (CL) after pH-cycling model (pHcm). Human dental enamel blocks were randomly divided into 6 groups (n=10): 1 - sound enamel bleached (S) with CP (Rembrandt/Den-Mat); 2 - S and submitted to pHcm; 3 - CL bleached with CP; 4 - CL stored in artificial saliva and submitted to pHcm; 5 - CL treated with placebo gel and submitted to pHcm; 6 - CL bleached with CP and submitted to pHcm. Enamel blocks with known initial KHN values were demineralized (groups 3 to 6) and submitted to 12 day pHcm (groups 2, 4, 5 and 6). After demineralization and treatments, KHN was determined and the specimens were examined using scanning electron microscopy (SEM). Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. The results showed that among CL groups (3 to 6) only the group 3 presented remineralization after treatments. S groups (1 and 2) showed higher KHN and presented less formation of porosities on enamel surface than CL groups after treatments. In conclusion, bleaching procedures on enamel with CL did not exacerbate the demineralization, but should be indicated with caution.

  19. Investigation on the remineralization effect of arginine toothpaste for early enamel caries: nanotribological and nanomechanical properties

    NASA Astrophysics Data System (ADS)

    Yu, Ping; Arola, Dwayne D.; Min, Jie; Yu, Dandan; Xu, Zhou; Li, Zhi; Gao, Shanshan

    2016-11-01

    Remineralization is confirmed as a feasible method to restore early enamel caries. While there is evidence that the 8% arginine toothpaste has a good remineralization effect by increasing surface microhardness, the repair effect on wear-resistance and nanomechanical properties still remains unclear. Therefore, this research was conducted to reveal the nanotribological and nanomechanical properties changes of early caries enamel after remineralized with arginine toothpaste. Early enamel caries were created in bovine enamel blocks, and divided into three groups according to the treatment solutions: distilled and deionized water (DDW group), arginine toothpaste slurry (arginine group) and fluoride toothpaste slurry (fluoride group). All of the samples were subjected to pH cycling for 12 d. The nanotribological and nanomechanical properties were evaluated via the nanoscratch and nanoindentation tests. The wear depth and scratch morphology were observed respectively by scanning probe microscopic (SPM) and scanning electron microscopy (SEM). Finally, x-ray photoelectron spectroscopy (XPS) was used for element analysis of remineralized surfaces. Results showed that the wear depth of early caries enamel decreased after remineralization treatment and both the nanohardness and elastic modulus increased. Compared with the fluoride group, the arginine group exhibited higher nanohardness and elastic modulus with higher levels of calcium, fluoride, nitrogen and phosphorus; this group also underwent less wear and related damage. Overall, the synergistic effect of arginine and fluoride in arginine toothpaste achieves better nanotribological and nanomechanical properties than the single fluoride toothpaste, which could have significant impact on fight against early enamel caries.

  20. Possibilities and potential roles of the functional peptides based on enamel matrix proteins in promoting the remineralization of initial enamel caries.

    PubMed

    Ieong, Cheng Cheng; Zhou, Xue Dong; Li, Ji Yao; Li, Wei; Zhang, Ling Lin

    2011-03-01

    Dental caries is the most common oral diseases, and it gives a serious threat to oral and general health. Fluoride, a classic anti-caries agent, has a profound effect on caries prevention and treatment. However, fluorosis and fluoride-resistant strains limit the further application of fluoride treatment. Therefore, it is still of significant benefit to seek alternatives, bringing more effective anti-caries agents. The potential role of enamel matrix proteins(EMPs) in promoting the regeneration of periodontal tissue and inducing bone have been proved. EMPs have been successfully applied in the field of periodontal disease and dental implants in recent years. Previous researches revealed that enamel matrix proteins had an important role in the synthesis of hydroxyapatite in vitro. Some experiments about the degeneration or removal of EMP suggest that enamel matrix proteins are related to the occurrence and development of caries. Based on evidences illustrated by these experiments, this paper hypothesizes that functional peptides based on the function and structure of EMPs could promote remineralization of enamel caries, which could perform as a suitable treatment to enamel caries. The hypothesis may lead a new direction in the study on the prevention and treatment of enamel caries, and further study of the anti-caries mechanisms of EMP will enable researchers to find out the most effective anti-caries peptides, which could be developed into a bionics anti-cariogenic agent.

  1. Elevated fluoride products enhance remineralization of advanced enamel lesions.

    PubMed

    ten Cate, J M; Buijs, M J; Miller, C Chaussain; Exterkate, R A M

    2008-10-01

    Caries prevention might benefit from the use of toothpastes containing over 1500 ppm F. With few clinical studies available, the aim of this pH-cycling study was to investigate the dose response between 0 and 5000 ppm F of de- and remineralization of advanced (> 150 microm) enamel lesions. Treatments included sodium and amine fluoride, and a fluoride-free control. Mineral uptake and loss were assessed from solution calcium changes and microradiographs. Treatments with 5000 ppm F both significantly enhanced remineralization and inhibited demineralization when compared with treatments with 1500 ppm F. Slight differences in favor of amine fluoride over sodium fluoride were observed. The ratio of de- over remineralization rates decreased from 13.8 to 2.1 in the range 0 to 5000 ppm F. As much as 71 (6)% of the remineralized mineral was calculated to be resistant to dissolution during subsequent demineralization periods. With 5000-ppm-F treatments, more demineralizing episodes per day (10 vs. 2 for placebo) would still be repaired by remineralization.

  2. [Enamel resistance to acid dissolution and its correlation with dental caries].

    PubMed

    Sánchez-Pérez, T L; Sáenz-Martínez, L P; Gómez-López, M E; Pérez-Quiroz, J

    1995-01-01

    Enamel resistance to acid dissolution is a factor which has an influence upon dental caries susceptibility. The objectives of this study were to determine enamel resistance to acid dissolution by applying the RM technique, and to correlate data obtained to the prevalence of dental caries. Two hundred and seventy one children between seven and nine years of age were chosen by non probabilistic sampling in two city districts, (six public schools in Mexico City). These children's central permanent incisives had already erupted. The DMF-T and dmf-t indexes were recorded, and the RM enamel resistance test was performed on them. A total of 56.4% of the subjects in the sample had very resistant enamel and 27.3%, less resistant enamel. A proportion of 57.9% was free of dental caries on the permanent dentition and 10% in the temporary dentition. The average obtained for the DMF-T index was 0.93 +/- 1.34 and that for dmf-t was 4.7 +/- 3.1. Data suggest that enamel resistance distribution is not homogeneous and this increases proportionally in relation to the eruption third (p < 0.05.) Spearman's correlation coefficient was found to be negative and statistically significant at p < 0.05. The RM technique showed the presence of individuals with different enamel resistance to acid dissolution.

  3. Automated detection of remineralization in simulated enamel lesions with PS-OCT

    NASA Astrophysics Data System (ADS)

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Previous in vitro and in vivo studies have demonstrated that polarization-sensitive optical coherence tomography (PS-OCT) can be used to nondestructively image the subsurface structure and measure the thickness of the highly mineralized transparent surface zone of caries lesions. There are structural differences between active lesions and arrested lesions, and the surface layer thickness may correlate with activity of the lesion. The purpose of this study was to develop a method that can be used to automatically detect and measure the thickness of the transparent surface layer in PS-OCT images. Automated methods of analysis were used to measure the thickness of the transparent layer and the depth of the bovine enamel lesions produced using simulated caries models that emulate demineralization in the mouth. The transparent layer thickness measured with PS-OCT correlated well with polarization light microscopy (PLM) measurements of all regions (r2=0.9213). This study demonstrates that PS-OCT can automatically detect and measure thickness of the transparent layer formed due to remineralization in simulated caries lesions.

  4. Nucleation and growth of hydroxyapatite nanocrystals for nondestructive repair of early caries lesions

    NASA Astrophysics Data System (ADS)

    Onuma, Kazuo; Yamagishi, Kazue; Oyane, Ayako

    2005-08-01

    Characterization of synthetic enamel formed by newly developed dental paste for repairing early caries lesions was performed using scanning and transmission electron microscopies and atomic force microscopy, with the chemical composition analysis using X-ray photoelectron spectroscopy. It was shown that the hydroxyapatite nanocrystals seamlessly grew in the interface between the paste and tooth enamel, and arranged their (0 0 0 1) face parallel to the tooth surface same as enamel apatite. The rapid growth of high crystalline large hydroxyapatite crystals by applying the paste is attributed to the dissociation of calcium phosphate clusters, Ca 9(PO 4) 6, which is the main growth unit of hydroxyapatite when it grows under physiological conditions, to ionic species in the concentrated and low pH phosphate solution.

  5. Detecting and Treating Occlusal Caries Lesions

    PubMed Central

    Stolpe, M.; Meyer-Lueckel, H.; Paris, S.

    2015-01-01

    The health gains and costs resulting from using different caries detection strategies might not only depend on the accuracy of the used method but also the treatment emanating from its use in different populations. We compared combinations of visual-tactile, radiographic, or laser-fluorescence–based detection methods with 1 of 3 treatments (non-, micro-, and invasive treatment) initiated at different cutoffs (treating all or only dentinal lesions) in populations with low or high caries prevalence. A Markov model was constructed to follow an occlusal surface in a permanent molar in an initially 12-y-old male German patient over his lifetime. Prevalence data and transition probabilities were extracted from the literature, while validity parameters of different methods were synthesized or obtained from systematic reviews. Microsimulations were performed to analyze the model, assuming a German health care setting and a mixed public-private payer perspective. Radiographic and fluorescence-based methods led to more overtreatments, especially in populations with low prevalence. For the latter, combining visual-tactile or radiographic detection with microinvasive treatment retained teeth longest (mean 66 y) at lowest costs (329 and 332 Euro, respectively), while combining radiographic or fluorescence-based detections with invasive treatment was the least cost-effective (<60 y, >700 Euro). In populations with high prevalence, combining radiographic detection with microinvasive treatment was most cost-effective (63 y, 528 Euro), while sensitive detection methods combined with invasive treatments were again the least cost-effective (<59 y, >690 Euro). The suitability of detection methods differed significantly between populations, and the cost-effectiveness was greatly influenced by the treatment initiated after lesion detection. The accuracy of a detection method relative to a “gold standard” did not automatically convey into better health or reduced costs. Detection

  6. Monitoring of enamel lesion remineralization by optical coherence tomography: an alternative approach towards signal analysis

    NASA Astrophysics Data System (ADS)

    Sadr, Alireza; Mandurah, Mona; Nakashima, Syozi; Shimada, Yasushi; Kitasako, Yuichi; Tagami, Junji; Sumi, Yasunori

    Early detection, monitoring and remineralization repair of enamel lesions are top research priorities in the modern dentistry focusing on minimal intervention concept for caries management. We investigate the use of swept-source optical coherence tomography system (SS-OCT) without polarization-sensing at 1319 nm wavelength developed for clinical dentistry (Dental OCT System Prototype 2, Panasonic Healthcare Co., Ltd., Japan) in quantitative assessment of artificial enamel lesions and their remineralization. Bovine enamel blocks were subjected to demineralization to create subsurface lesions approximately 130 μm in depth over 2 weeks, and subjected to remineralization in solution containing bioavailable calcium and 1ppm fluoride at pH 6.5 for 2 weeks. Cross-sectional images of sound, demineralized and remineralized specimens were captured under hydrated conditions by the OCT. Finally, the specimens were cut into sections for nanoindentation to measure hardness through the lesion under 2mN load. Reflectivity had increased with demineralization. OCT images of lesions showed a boundary closely suggesting the lesion depth that gradually progressed with demineralization time. After remineralization, the boundary depth gradually decreased and nanoindentation showed over 60% average hardness recovery rate. A significant negative correlation was found between the slope power-law regression as a measure of attenuation and overall nanohardness for a range of data covering sound, demineralized and remineralized areas. In conclusion, OCT could provide clear images of early enamel lesion extent and signal attenuation could indicate its severity and recovery. Clinical data of natural lesions obtained using Dental OCT and analyzed by this approach will also be presented. Study supported by GCOE IRCMSTBD and NCGG.

  7. Clinical monitoring of early caries lesions using cross polarization optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Fried, Daniel; Staninec, Michal; Darling, Cynthia L.; Chan, Kenneth H.; Pelzner, Roger B.

    New methods are needed for the nondestructive measurement of tooth demineralization and remineralization and to monitor the progression of incipient caries lesions (tooth decay) for effective nonsurgical intervention and to evaluate the performance of anti-caries treatments such as chemical treatments or laser irradiation. Studies have shown that optical coherence tomography (OCT) has great potential to fulfill this role, since it can be used to measure the depth and severity of early lesions with an axial resolution exceeding 10-μm. It is easy to apply in vivo and it can be used to image the convoluted topography of tooth occlusal surfaces. In this paper we present early results from two clinical studies underway to measure the effect of fluoride intervention on early lesions. CP-OCT was used to monitor early lesions on enamel and root surfaces before and after intervention with fluoride varnish. The lesion depth and internal structure were resolved for all the lesions examined and some lesions had well defined surface zones of lower reflectivity that may be indicative of arrested lesions. Changes were also noted in the structure of some of the lesions after fluoride intervention.

  8. A Microbeam Small-Angle X-ray Scattering Study on Enamel Crystallites in Subsurface Lesion

    NASA Astrophysics Data System (ADS)

    Yagi, N.; Ohta, N.; Matsuo, T.; Tanaka, T.; Terada, Y.; Kamasaka, H.; Kometani, T.

    2010-10-01

    The early caries lesion in bovine tooth enamel was studied by two different X-ray diffraction systems at the SPring-8 third generation synchrotron radiation facility. Both allowed us simultaneous measurement of the small and large angle regions. The beam size was 6μm at BL40XU and 50μm at BL45XU. The small-angle scattering from voids in the hydroxyapatite crystallites and the wide-angle diffraction from the hydroxyapatite crystals were observed simultaneously. At BL40XU an X-ray image intensifier was used for the small-angle and a CMOS flatpanel detector for the large-angle region. At BL45XU, a large-area CCD detector was used to cover both regions. A linear microbeam scan at BL40XU showed a detailed distribution of voids and crystals and made it possible to examine the structural details in the lesion. The two-dimensional scan at BL45XU showed distribution of voids and crystals in a wider region in the enamel. The simultaneous small- and wide-angle measurement with a microbeam is a powerful tool to elucidate the mechanisms of demineralization and remineralization in the early caries lesion.

  9. INTRAPUPAL TEMPERATURE VARIATION DURING ER,CR:YSGG ENAMEL IRRADIATION ON CARIES PREVENTION

    PubMed Central

    de Freitas, Patrícia Moreira; Soares-Geraldo, Débora; Biella-Silva, Ana Cristina; Silva, Amanda Verna; da Silveira, Bruno Lopes; Eduardo, Carlos de Paula

    2008-01-01

    Studies have shown the cariostatic effect of Er,Cr:YSGG (2.78 μm) laser irradiation on human enamel and have suggested its use on caries prevention. However there are still no reports on the intrapulpal temperature increase during enamel irradiation using parameters for caries prevention. The aim of this in vitro study was to evaluate the temperature variation in the pulp chamber during human enamel irradiation with Er,Cr:YSGG laser at different energy densities. Fifteen enamel blocks obtained from third molars (3 x 3 x 3 mm) were randomly assigned to 3 groups (n=5): G1 – Er,Cr:YSGG laser 0.25 W, 20 Hz, 2.84 J/cm2, G2 – Er,Cr:YSGG laser 0.50 W, 20 Hz, 5.68 J/cm2, G3 – Er,Cr:YSGG laser 0.75 W, 20 Hz, 8.52 J/cm2. During enamel irradiation, two thermocouples were fixed in the inner surface of the specimens and a thermal conducting paste was used. One-way ANOVA did not show statistically significant difference among the experimental groups (α=0.05). There was intrapulpal temperature variation ≤0.1°C for all irradiation parameters. In conclusion, under the tested conditions, the use of Er,Cr:YSGG laser with parameters set for caries prevention lead to an acceptable temperature increase in the pulp chamber. PMID:19089198

  10. Assessment of the remineralization in simulated enamel lesions via dehydration with near-IR reflectance imaging

    NASA Astrophysics Data System (ADS)

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2015-02-01

    Previous studies have demonstrated that near-IR imaging can be used to nondestructively monitor the severity of enamel lesions. Arrested lesions typically have a highly mineralized surface layer that reduces permeability and limits diffusion into the lesion. The purpose of this study was to investigate whether the rate of water loss correlates with the degree of remineralization using near-IR reflectance imaging. Artificial bovine (n=15) enamel lesions were prepared by immersion in a demineralization solution for 24 hours and they were subsequently placed in an acidic remineralization solution for different periods. The samples were dehydrated using an air spray for 30 seconds and surfaces were imaged using an InGaAs camera at 1300-1700 nm wavelengths. Near-IR reflectance intensity differences before and after dehydration decreased with longer periods of remineralization. This study demonstrated that near-IR reflectance imaging was suitable for the detection of remineralization in simulated caries lesions and near-IR wavelengths longer than 1400 nm are well suited for the assessment of remineralization.

  11. Effects of XeCl excimer lasers and fluoride application on artificial caries-like lesions

    NASA Astrophysics Data System (ADS)

    Wilder-Smith, Petra B. B.; Phan, T.; Liaw, Lih-Huei L.; Berns, Michael W.

    1994-09-01

    In this study the affects of a pulsed excimer laser emitting at 308 nm (XeCl) on enamel susceptibility to artificial caries-like lesions were investigated. Additional effects of fluoride (F) application were also studied and SEC examinations performed. Sixty-four extracted human molar teeth were coated with acid resistant varnish leaving four windows, then sectioned, leaving one window on each tooth quarter. The windows were treated in one of the following ways: untreated (control), or lased, or exposed to 4 min. APF (1.23% F) before lasing, or exposed to 4 min. APF (1.23% F) after lasing. After lasing, microhardness profiles were obtained and SEM was performed. Caries resistance was generally increased at moderate fluences. F application combined with lasing enhanced caries resistance at some parameters. SEM showed effects ranging from minimal to localized effects to extended glazing. Pulsed excimer laser irradiation, especially combined with topical F application can inhibit development of artificial caries-like lesions.

  12. The effect of whitening agents on caries susceptibility of human enamel.

    PubMed

    Al-Qunaian, Talal A

    2005-01-01

    This in vitro study evaluated whether the treatment of human enamel with whitening agents containing different concentrations of carbamide or hydrogen peroxide changes the susceptibility of enamel to caries. Twenty-four sound human incisors were selected for this study. For each tooth, the crown was sectioned into two halves in the cervical-incisal direction. One half of the sectioned tooth was treated and the other half was used as a control specimen. Each half was randomly divided into three treatment groups (eight two-halves/group). The whitening agents were 10% carbamide peroxide, 20% carbamide peroxide with fluoride and 35% hydrogen peroxide. Following pretreatment, the specimens were demineralized for four days in an in vitro microbial caries model and then analyzed using a confocal laser scanning microscope (CLSM). Results showed that there were no significant differences between the treated and controlled specimens for teeth treated with 10% carbamide peroxide or 35% hydrogen peroxide. However, specimens treated with 20% carbamide peroxide with FP (0.11% fluoride and potassium nitrate) were less susceptible to caries than their controls at p < or = 0.05. In conclusion, application of bleaching agents does not increase the caries susceptibility of human enamel.

  13. Effects of enamel matrix genes on dental caries are moderated by fluoride exposures.

    PubMed

    Shaffer, John R; Carlson, Jenna C; Stanley, Brooklyn O C; Feingold, Eleanor; Cooper, Margaret; Vanyukov, Michael M; Maher, Brion S; Slayton, Rebecca L; Willing, Marcia C; Reis, Steven E; McNeil, Daniel W; Crout, Richard J; Weyant, Robert J; Levy, Steven M; Vieira, Alexandre R; Marazita, Mary L

    2015-02-01

    Dental caries (tooth decay) is the most common chronic disease, worldwide, affecting most children and adults. Though dental caries is highly heritable, few caries-related genes have been discovered. We investigated whether 18 genetic variants in the group of non-amelogenin enamel matrix genes (AMBN, ENAM, TUFT1, and TFIP11) were associated with dental caries experience in 13 age- and race-stratified samples from six parent studies (N = 3,600). Linear regression was used to model genetic associations and test gene-by-fluoride interaction effects for two sources of fluoride: daily tooth brushing and home water fluoride concentration. Meta-analysis was used to combine results across five child and eight adult samples. We observed the statistically significant association of rs2337359 upstream of TUFT1 with dental caries experience via meta-analysis across adult samples (p < 0.002) and the suggestive association for multiple variants in TFIP11 across child samples (p < 0.05). Moreover, we discovered two genetic variants (rs2337359 upstream of TUFT1 and missense rs7439186 in AMBN) involved in gene-by-fluoride interactions. For each interaction, participants with the risk allele/genotype exhibited greater dental caries experience only if they were not exposed to the source of fluoride. Altogether, these results confirm that variation in enamel matrix genes contributes to individual differences in dental caries liability, and demonstrate that the effects of these genes may be moderated by protective fluoride exposures. In short, genes may exert greater influence on dental caries in unprotected environments, or equivalently, the protective effects of fluoride may obviate the effects of genetic risk alleles.

  14. Effects of enamel matrix genes on dental caries are moderated by fluoride exposures

    PubMed Central

    Shaffer, John R.; Carlson, Jenna C.; Stanley, Brooklyn O. C.; Feingold, Eleanor; Cooper, Margaret; Vanyukov, Michael M.; Maher, Brion S.; Slayton, Rebecca L.; Willing, Marcia C.; Reis, Steven E.; McNeil, Daniel W.; Crout, Richard J.; Weyant, Robert J.; Levy, Steven M.; Vieira, Alexandre R.; Marazita, Mary L.

    2014-01-01

    Dental caries (tooth decay) is the most common chronic disease, worldwide, affecting most children and adults. Though dental caries is highly heritable, few caries-related genes have been discovered. We investigated whether 18 genetic variants in the group of nonamelogenin enamel matrix genes (AMBN, ENAM, TUFT1, and TFIP11) were associated with dental caries experience in 13 age- and race-stratified samples from six parent studies (N=3,600). Linear regression was used to model genetic associations and test gene-byfluoride interaction effects for two sources of fluoride: daily tooth brushing and home water fluoride concentration. Meta-analysis was used to combine results across five child and eight adult samples. We observed the statistically significant association of rs2337359 upstream of TUFT1 with dental caries experience via meta-analysis across adult samples (p<0.002) and the suggestive association for multiple variants in TFIP11 across child samples (p<0.05). Moreover, we discovered two genetic variants (rs2337359 upstream of TUFT1 and missense rs7439186 in AMBN) involved in gene-by-fluoride interactions. For each interaction, participants with the risk allele/genotype exhibited greater dental caries experience only if they were not exposed to the source of fluoride. Altogether, these results confirm that variation in enamel matrix genes contributes to individual differences in dental caries liability, and demonstrate that the effects of these genes may be moderated by protective fluoride exposures. In short, genes may exert greater influence on dental caries in unprotected environments, or equivalently, the protective effects of fluoride may obviate the effects of genetic risk alleles. PMID:25373699

  15. Prevalence and Association of Developmental Defects of Enamel with, Dental- Caries and Nutritional Status in Pre-School Children, Lucknow

    PubMed Central

    Saha, Sabyasachi; Jagannath, G.V.; Singh, Sanjay

    2015-01-01

    Background Developmental Defects of Enamel in the primary dentition may be associated and predictors of dental caries and nutritional status. The aim of the present study was to assess the Prevalence of Developmental Defects of Enamel and its Association with, Dental-Caries and Nutritional Status in Pre-School Children of Lucknow, India. Materials and Methods Multistage Sampling was done. A total of 302 pre-school (Rural and Urban) children were examined. Type III examination was conducted with WHO Probe. Developmental Enamel Defects (DED) and Dental Caries were assessed using WHO (1997) Proforma. Results The prevalence of DED of any type was 39.9% with that of demarcated opacities being the highest, followed by hypoplasia. The most frequently affected teeth were maxillary anterior teeth, while the least affected teeth were mandibular incisors. The mean dmft was 3.5. A positive association between DED and caries was observed. Association between Dental Caries & BMI was non-significant whereas Pearson correlation showed a negative correlation between the two. Conclusion The prevalence of enamel defects and caries was high, as the enamel defects were strongly associated with caries. PMID:26557622

  16. Influence of CO2 (10.6 μm) and Nd:YAG laser irradiation on the prevention of enamel caries around orthodontic brackets.

    PubMed

    Seino, Priscila Yumi; Freitas, Patrícia Moreira; Marques, Márcia Martins; de Souza Almeida, Fernanda Campos; Botta, Sérgio Brossi; Moreira, Maria Stella Nunes Araújo

    2015-02-01

    One possible undesirable consequence of orthodontic therapy is the development of incipient caries lesions of enamel around brackets. The aim of this study was to compare the effects of CO2 (λ = 10.6 μm) and Nd:YAG (λ = 1,064 nm) lasers associated or not with topical fluoride application on the prevention of caries lesions around brackets. Brackets were bonded to the enamel of 65 premolars. The experimental groups (n = 13) were: G1--application of 1.23% acidulated fluoride phosphate gel (AFP, control); G2--Nd:YAG laser irradiation (0.6 W, 84.9 J/cm(2), 10 Hz, 110 μs, contact mode); G3--Nd:YAG laser irradiation associated with AFP; G4--CO2 laser irradiation (0.5 W, 28.6 J/cm(2), 50 Hz, 5 μs, and 10 mm focal distance); and G5--CO2 laser irradiation associated with AFP. Quantitative light-induced fluorescence was used to assess enamel demineralization. The data were statistically compared (α = 5%). The highest demineralization occurred in the Nd:YAG laser group (G2, 26.15% ± 1.94). The demineralization of all other groups was similar to that of the control group. In conclusion, CO2 laser alone was able to control enamel demineralization around brackets at the same level as that obtained with topical fluoride application.

  17. In vitro evaluation of the efficacy of laser fluorescence (DIAGNOdent) to detect demineralization and remineralization of smooth enamel lesions

    PubMed Central

    Bahrololoomi, Zahra; Musavi, Seyed Ahmad; Kabudan, Mona

    2013-01-01

    Objective: Early detection of smooth surface lesions is important for appropriate management and monitoring of dental caries. The purpose of this in vitro study was to evaluate the efficacy of laser fluorescence to detect demineralization and remineralization of smooth enamel surfaces. Materials and Methods: In this in vitro study, 132 enamel blocks of semi-impacted human third molars were obtained; artificial caries lesions were induced and they were submitted to the pH-cycling process to create remineralization. Superficial microhardness (SMH) and laser fluorescence (LF) analysis were performed at baseline, after demineralization, and remineralization processes. The data were analyzed by Statistical Package for Social Sciences (SPSS)-16 using analysis of variance (ANOVA), Paired samples t-test, and Pearson's correlation test. Results: There was a significant difference between SMH values at baseline, after demineralization and after remineralization. Also, a statistically significant difference was observed between LF values in these three stages. The LF values increased after demineralization and then decreased after remineralization, and the SMH values decreased after demineralization and increased after remineralization. There was an inverse relationship between SMH and LF only at baseline and after demineralization, but not after remineralization. Conclusion: The results showed that LF is an appropriate method for detection of demineralization in an in vitro condition in smooth enamel lesions, but it was not so efficient in the detection of remineralization. PMID:23956542

  18. Remineralization potential of nano-hydroxyapatite on initial enamel lesions: an in vitro study.

    PubMed

    Huang, S; Gao, S; Cheng, L; Yu, H

    2011-01-01

    The application of nano-hydroxyapatite (HA) in the repair of early caries lesion has received considerable attention. Neither the effects of the size of HA nor the effects of the effective pH range of nano-HA on remineralization have been investigated comprehensively, and the protective mechanism is still open for debate. To address these factors, the remineralization effect of nano-HA on demineralized bovine enamel is investigated under pH cycling conditions through surface and cross-sectional microhardness (CSMH) tests and polarized light microscopy (PLM). The percentage of surface microhardness recovery and integrated mineral loss obtained from CSMH tests demonstrated that nano-HA provides better remineralization than micro-HA. However, detailed investigation using CSMH tests and PLM indicated that nano-HA helped mineral deposition predominantly in the outer layer of the lesion and only had a limited capacity to reduce lesion depth. Nevertheless, the remineralization effect of nano-HA increased significantly when the pH was less than 7.0. Clearly, nano-HA has potential as an effective repair material and anticaries agent. Our findings also suggest that both the particle- and ion-mediated remineralization pathways in nano-HA may contribute to the repair of demineralized enamel.

  19. Effect of ammonium hexafluorosilicate application for arresting caries treatment on demineralized primary tooth enamel.

    PubMed

    Hosoya, Yumiko; Tadokoro, Katsumi; Otani, Hideji; Hidaka, Kiyoshi; Inoue, Takashi; Miyazaki, Masashi; Tay, Franklin R

    2013-01-01

    Ammonium hexafluorosilicate (AHF) has been applied to arrest caries without discoloration. The purpose of this study was to observe structural and elemental changes of demineralized and AHF applied primary tooth enamel. Enamel from the labial surface of 20 primary canines was divided into an unground side and ground side at the center of the tooth, and demineralized with 35% phosphoric acid for 6 min. The teeth were divided into 4 groups according to a 3-min application of AHF and 1 week of soaking in artificial saliva, as follows: group A (neither AHF nor saliva), group B (only saliva), group C (only AHF), and group D (AHF and saliva), and then subdivided according to whether the enamel was ground or unground. Specimens were analyzed with scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The data were statistically analyzed using ANOVA and Fisher's PLSD test at α = 0.05. In groups A and B, prism structures were seen, however, in groups C and D, enamel surfaces were covered with spherical particles. Ca/P ratio was significantly higher in groups C and D than in groups A and B. There was no significant difference between ground and unground enamel in the content of any element. The values for F, Na, Mg and Si persents and Ca/P ratio were significantly higher for the enamel surface than for points 10-30 µm beneath the surface. Results of this study suggest the possibility that AHF treatment arrests caries, although further study will be required to confirm this result.

  20. Management of Post-orthodontic White Spot Lesions and Subsequent Enamel Discoloration with Two Microabrasion Techniques

    PubMed Central

    Jahanbin, Arezoo; Ameri, Hamideh; Shahabi, Mostafa; Ghazi, Ala

    2015-01-01

    Statement of the Problem Demineralization of enamel adjacent to orthodontic appliances frequently occurs, commonly due to insufficient oral hygiene. Purpose The aim of this study was to compare two microabrasion techniques on improving the white spot lesions as well as subsequent enamel discoloration. Materials and Method Sixty extracted premolar teeth without caries and hypoplasia were selected for this study. White spot lesions were artificially induced on the buccal surface of each tooth. Teeth were randomly assigned to three treatment groups, each treated with pumice powder as the control, microabrasion with 18% HCl, and microabrasion with 37% H3PO4. Subsequently, the three groups were daily immersed for five minutes in a tea-coffee solution for a period of one week. Colorimetric evaluation was done before and after formation of white spot lesions, after microabrasion, and after immersion in the colored solution; then the color differences (∆E) were calculated. Statistical analysis was performed by multiple measurement analysis and the Tukey’s test. Results This study showed that ∆E between the stages of white spot formation and microabrasion for H3PO4 was more than other groups and for the pumice powder group it was less than the others. Furthermore, there was a significant difference between ∆E of the three study groups (p= 0.017). Additionally, ∆E after placing the teeth in the colored solution and microabrasion was the highest for the HCl group and the lowest for the pumice powder group. There was also a significant difference between the three groups (p= 0.000). Conclusion Pumice powder alone had similar effects as 18% HCl on removing the white spot lesions. Nevertheless, 18% HCl makes the enamel susceptible for subsequent color staining more than the other microabrasion methods. PMID:26106636

  1. Terahertz pulsed imaging study to assess remineralization of artificial caries lesions

    NASA Astrophysics Data System (ADS)

    Churchley, David; Lynch, Richard J. M.; Lippert, Frank; O'Bryan Eder, Jennifer Susan; Alton, Jesse; Gonzalez-Cabezas, Carlos

    2011-02-01

    We compare terahertz-pulsed imaging (TPI) with transverse microradiography (TMR) and microindentation to measure remineralization of artificial caries lesions. Lesions are formed in bovine enamel using a solution of 0.1 M lactic acid/0.2% Carbopol C907 and 50% saturated with hydroxyapatite adjusted to pH 5.0. The 20-day experimental protocol consists of four 1 min treatment periods with dentifrices containing 10, 675, 1385, and 2700 ppm fluoride, a 4-h/day acid challenge, and, for the remaining time, specimens are stored in a 50:50 pooled human/artificial saliva mixture. Each specimen is imaged at the focal point of the terahertz beam (data-point spacing = 50 μm). The time-domain data are used to calculate the refractive index volume percent profile throughout the lesion, and the differences in the integrated areas between the baseline and post-treatment profiles are used to calculate ΔΔZ(THz). In addition, the change from baseline in both the lesion depth and the intensity of the reflected pulse from the air/enamel interface is determined. Statistically significant Pearson correlation coefficients are observed between TPI and TMR/microindentation (P < 0.05). We demonstrate that TPI has potential as a research tool for hard tissue imaging.

  2. Dental Caries and Enamel Defects in Very Low Birth Weight Adolescents

    PubMed Central

    Nelson, S.; Albert, J.M.; Lombardi, G.; Wishnek, S.; Asaad, G.; Kirchner, H.L.; Singer, L.T.

    2011-01-01

    Objectives The purpose of this study was to examine developmental enamel defects and dental caries in very low birth weight adolescents with high risk (HR-VLBW) and low risk (LR-VLBW) compared to full-term (term) adolescents. Methods The sample consisted of 224 subjects (80 HR-VLBW, 59 LR-VLBW, 85 term adolescents) recruited from an ongoing longitudinal study. Sociodemographic and medical information was available from birth. Dental examination of the adolescent at the 14-year visit included: enamel defects (opacity and hypoplasia); decayed, missing, filled teeth of incisors and molars (DMFT-IM) and of overall permanent teeth (DMFT); Simplified Oral Hygiene Index for debris/calculus on teeth, and sealant presence. A caregiver questionnaire completed simultaneously assessed dental behavior, access, insurance status and prevention factors. Hierarchical analysis utilized the zero-inflated negative binomial model and zero-inflated Poisson model. Results The zero-inflated negative binomial model controlling for sociodemographic variables indicated that the LR-VLBW group had an estimated 75% increase (p < 0.05) in number of demarcated opacities in the incisors and first molar teeth compared to the term group. Hierarchical modeling indicated that demarcated opacities were a significant predictor of DMFT-IM after control for relevant covariates. The term adolescents had significantly increased DMFT-IM and DMFT scores compared to the LR-VLBW adolescents. Conclusion LR-VLBW was a significant risk factor for increased enamel defects in the permanent incisors and first molars. Term children had increased caries compared to the LR-VLBW group. The effect of birth group and enamel defects on caries has to be investigated longitudinally from birth. PMID:20975268

  3. Characterizing and identifying incipient carious lesions in dental enamel using micro-Raman spectroscopy.

    PubMed

    Mohanty, B; Dadlani, D; Mahoney, D; Mann, A B

    2013-01-01

    Early detection of dental caries is vital if improved patient outcomes are to be achieved by reversal of the demineralization process. Current techniques used by dentists for identifying carious lesions are effective in identifying more advanced lesions, but do not have sufficient sensitivity and specificity to detect them at the earliest stages. This study focused on characterizing the growth of incipient carious lesions in vitro using micro-Raman spectroscopy. The incipient carious lesions were grown on the buccal faces of human molars by controlled exposure to lactic acid. Lesions were cross-sectioned to expose the subsurface body of the lesion and then examined using micro-Raman spectroscopy. The intensity of the phosphate peaks in the Raman spectra was found to differ significantly between healthy enamel and the demineralized region of the lesions. The sensitivity of the phosphate peaks to the degree of demineralization was observed by taking a series of spectra over the cross section of the lesions. This revealed that the body of the lesion is highly demineralized, but in a narrow surface region (up to 10 µm) there is little demineralization. All the phosphate peaks were found to be sensitive to the degree of demineralization; however, changes in the intensity of the pronounced phosphate peak at 961 cm(-1) offer the most promise for identifying lesions. The results indicate that micro-Raman spectroscopy has both the sensitivity and selectivity to identify incipient carious lesions, but the presence of a surface layer with a relatively high mineral content could complicate the analysis.

  4. Radiopaque Tagging Masks Caries Lesions following Incomplete Excavation in vitro.

    PubMed

    Schwendicke, F; Meyer-Lueckel, H; Schulz, M; Dörfer, C E; Paris, S

    2014-06-01

    One-step incomplete excavation seals caries-affected dentin under a restoration and appears to be advantageous in the treatment of deep lesions. However, it is impossible to discriminate radiographically between intentionally left, arrested lesions and overlooked or active lesions. This diagnostic uncertainty decreases the acceptance of minimally invasive excavation and might lead to unnecessary re-treatment of incompletely excavated teeth. Radiopaque tagging of sealed lesions might mask arrested lesions and assist in discrimination from progressing lesions. Therefore, we microradiographically screened 4 substances (SnCl2, AgNO3, CsF, CsCH3COO) for their effect on artificial lesions. Since water-dissolved tin chloride (SnCl2×Aq) was found to stably mask artificial lesions, we then investigated its radiographic effects on progressing lesions. Natural lesions were incompletely excavated and radiopaque tagging performed. Grey-value differences (△GV) between sound and carious dentin were determined and radiographs assessed by 20 dentists. While radiographic effects of SnCl2×Aq were stable for non-progressing lesions, they significantly decreased during a second demineralization (p < .001, t test). For natural lesions, tagging with SnCl2×Aq significantly reduced △GV (p < .001, Wilcoxon). Tagged lesions were detected significantly less often than untagged lesions (p < .001). SnCl2×Aq was suitable to mask caries-affected dentin and discriminate between arrested and progressing lesions in vitro. Radiopaque tagging could resolve diagnostic uncertainties associated with incomplete excavation.

  5. High contrast optical imaging methods for image guided laser ablation of dental caries lesions

    NASA Astrophysics Data System (ADS)

    LaMantia, Nicole R.; Tom, Henry; Chan, Kenneth H.; Simon, Jacob C.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Laser based methods are well suited for automation and can be used to selectively remove dental caries to minimize the loss of healthy tissues and render the underlying enamel more resistant to acid dissolution. The purpose of this study was to determine which imaging methods are best suited for image-guided ablation of natural non-cavitated carious lesions on occlusal surfaces. Multiple caries imaging methods were compared including near-IR and visible reflectance and quantitative light fluorescence (QLF). In order for image-guided laser ablation to be feasible, chemical and physical modification of tooth surfaces due to laser irradiation cannot greatly reduce the contrast between sound and demineralized dental hard tissues. Sound and demineralized surfaces of 48 extracted human molar teeth with non-cavitated lesions were examined. Images were acquired before and after laser irradiation using visible and near-IR reflectance and QLF at several wavelengths. Polarization sensitive-optical coherence tomography was used to confirm that lesions were present. The highest contrast was attained at 1460-nm and 1500-1700-nm, wavelengths coincident with higher water absorption. The reflectance did not decrease significantly after laser irradiation for those wavelengths.

  6. Gum containing calcium fluoride reinforces enamel subsurface lesions in situ.

    PubMed

    Kitasako, Y; Sadr, A; Hamba, H; Ikeda, M; Tagami, J

    2012-04-01

    The aim of this study was to assess the effect of chewing gum containing phosphoryl oligosaccharides of calcium (POs-Ca) and a low concentration of fluoride (F) on the hardness of enamel subsurface lesions, utilizing a double-blind, randomized, and controlled in situ model. Fifteen individuals wore removable lingual appliances with 3 bovine-enamel insets containing subsurface demineralized lesions. Three times a day for 14 days, they chewed one of the 3 chewing gums (placebo, POs-Ca, POs-Ca+F). After the treatment period, cross-sectional mineral content, nanoindentation hardness, and fluoride ion mapping by time-of-flight secondary ion mass spectrometry (TOF-SIMS) were evaluated. Although there were no statistical differences in overall mineral content and hardness recovery rates between POs-Ca and POs-Ca+F subsurface lesions (p > 0.05), nanoindentation at 1-μm distance increments from the surface showed statistical differences in hardness recovery rate between POs-Ca and POs-Ca+F in the superficial 20-μm region (p < 0.05). Fluoride mapping revealed distribution of the ion up to 20 μm from the surface in the POs-Ca+F group. Nanoindentation and TOF-SIMS results highlighted the benefits of bioavailability of fluoride ion on reinforcement of the superficial zone of subsurface lesions in situ (NCT01377493).

  7. Nondestructive assessment of the severity of occlusal caries lesions with near-infrared imaging at 1310 nm

    NASA Astrophysics Data System (ADS)

    Lee, Chulsung; Lee, Dustin; Darling, Cynthia L.; Fried, Daniel

    2010-07-01

    The high transparency of dental enamel in the near-infrared (NIR) at 1310 nm can be exploited for imaging dental caries without the use of ionizing radiation. The objective of this study is to determine whether the lesion contrast derived from NIR imaging in both transmission and reflectance can be used to estimate lesion severity. Two NIR imaging detector technologies are investigated: a new Ge-enhanced complementary metal-oxide-semiconductor (CMOS)-based NIR imaging camera, and an InGaAs focal plane array (FPA). Natural occlusal caries lesions are imaged with both cameras at 1310 nm, and the image contrast between sound and carious regions is calculated. After NIR imaging, teeth are sectioned and examined using polarized light microscopy (PLM) and transverse microradiography (TMR) to determine lesion severity. Lesions are then classified into four categories according to lesion severity. Lesion contrast increases significantly with lesion severity for both cameras (p<0.05). The Ge-enhanced CMOS camera equipped with the larger array and smaller pixels yields higher contrast values compared with the smaller InGaAs FPA (p<0.01). Results demonstrate that NIR lesion contrast can be used to estimate lesion severity.

  8. The effects of 1% pyrophosphate and 0.02% sodium fluoride on artificial caries lesions in vivo.

    PubMed

    Mellberg, J R; Petrou, I D; Deutchman, M; Grote, N

    1988-12-01

    We evaluated the potential of a pyrophosphate-fluoride solution to affect the remineralizing-demineralizing equilibrium, i.e., caries-inhibiting/-promoting effects on enamel in vivo. Fifteen subjects carried dentin blocks and enamel thin sections with artificial caries lesions in removable partial dentures for periods of two weeks, during which time they rinsed twice daily in a double-blind, randomized cross-over design with solutions containing (a) 90 ppm F, (b) 90 ppm F and 1% pyrophosphate, or (c) no active agents (placebo). A severe cariogenic challenge provided to the lesions by plaque under a stainless steel mesh cover resulted in the placebo-treated lesions losing 70.2% +/- 72.1% mineral. The pyrophosphate rinse with fluoride held the mineral loss to only 28.1 +/- 52.8%, while the fluoride rinse without pyrophosphate held the loss to 24.2 +/- 50.1%. The differences between the fluoride and placebo results were significant (p less than 0.01), but the difference between the two fluoride groups was not. A large amount of fluoride was deposited in the dentin lesions. In the surface layer, the concentration was increased from 1000 ppm F to more than 2300 ppm F by both fluoride treatments. The concentration of fluoride in both groups of fluoride-treated lesions further increased to more than 3500 ppm F in the approximate center of the lesion before declining in deeper layers toward the level found in the placebo-treated group. The findings from both mineral change and fluoride uptake phases of this study show that in the presence of 90 ppm F, 1% pyrophosphate did not promote demineralization of artificial caries lesions.

  9. Prevalence of candida albicans in dental plaque and caries lesion of early childhood caries (ECC) according to sampling site

    PubMed Central

    Ghasempour, Maryam; Sefidgar, Seyed Ali Asghar; Eyzadian, Haniyeh; Gharakhani, Samaneh

    2011-01-01

    Background: Candida albicans may have cariogenic potential but its role in caries etiology has not been established. The aim of this study was to determine candida albicans in supragingival dental plaque and infected dentine of cervical and proximal in early childhood caries (ECC). Methods: This cross-sectional study was carried out on 6o children aged 2-5 years, which were divided into 3 groups: children with at least one cervical caries; children with at least one proximal caries and caries-free. The infected dentine was collected from cervical and proximal caries lesions and plaque samples were collected from the three groups in order to compare the frequency of candida albicans in the collected sites. All samples were cultured in Sabouraud and CHROMagar medium and the cases that were positive for candida albicans were cultured in germ tube. Data were collected and analyzed. Results: The mean age of the children was 3.9 years. From 100 samples, candida albicans samples were isolated in 55%, mold fungi were found in 29% cases and there was no fungal growth in 16% of the samples. In plaque samples, candida albicans were found in 15% of caries-free samples, 20% of the proximal and 80% of the cervical caries. In samples extracted from the caries, candida albicans were found in 60% of the proximal and 100% of the cervical caries. Mothers with university educational level had children with more cervical decays, caries free and proximal caries, respectively. Conclusion: The results showed that prevalence of Candida albicans in dental plaque and caries lesions of children with early childhood caries were relatively high and the prevalence was higher in cervical caries group. PMID:24551436

  10. Children with severe early childhood caries: streptococci genetic strains within carious and white spot lesions

    PubMed Central

    Gilbert, Kenneth; Joseph, Raphael; Vo, Alex; Patel, Trusha; Chaudhry, Samiya; Nguyen, Uyen; Trevor, Amy; Robinson, Erica; Campbell, Margaret; McLennan, John; Houran, Farielle; Wong, Tristan; Flann, Kendra; Wages, Melissa; Palmer, Elizabeth A.; Peterson, John; Engle, John; Maier, Tom; Machida, Curtis A.

    2014-01-01

    Background and objectives Mutans streptococci (MS) are one of the major microbiological determinants of dental caries. The objectives of this study are to identify distinct MS and non-MS streptococci strains that are located at carious sites and non-carious enamel surfaces in children with severe early childhood caries (S-ECC), and assess if cariogenic MS and non-cariogenic streptococci might independently exist as primary bacterial strains on distinct sites within the dentition of individual children. Design Dental plaque from children (N=20; aged 3–6) with S-ECC was collected from carious lesions (CLs), white spot lesions (WSLs) and non-carious enamel surfaces. Streptococcal isolates (N=10–20) from each site were subjected to polymerase chain reaction (PCR) to identify MS, and arbitrarily primed-PCR for assignment of genetic strains. Primary strains were identified as ≥50% of the total isolates surveyed at any site. In several cases, strains were characterized for acidurity using ATP-driven bioluminescence and subjected to PCR-determination of potential MS virulence products. Identification of non-MS was determined by 16S rRNA gene sequencing. Results Sixty-four independent MS or non-MS streptococcal strains were identified. All children contained 1–6 strains. In many patients (N=11), single primary MS strains were identified throughout the dentition. In other patients (N=4), primary MS strains were identified within CLs that were distinct from primary strains found on enamel. Streptococcus gordonii strains were identified as primary strains on enamel or WSLs in four children, and in general were less aciduric than MS strains. Conclusions Many children with S-ECC contained only a single primary MS strain that was present in both carious and non-carious sites. In some cases, MS and non-cariogenic S. gordonii strains were found to independently exist as dominant strains at different locations within the dentition of individual children, and the aciduric

  11. Effects of Enamel Fluorosis and Dental Caries on Quality of Life

    PubMed Central

    Onoriobe, U.; Rozier, R.G.; Cantrell, J.; King, R.S.

    2014-01-01

    The objectives of this study were to determine the impact of enamel fluorosis and dental caries on oral health–related quality of life (OHRQoL) in North Carolina schoolchildren and their families. Students (n = 7,686) enrolled in 398 classrooms in grades K-12 were recruited for a onetime survey. Parents of students in grades K-3 and 4-12 completed the Early Childhood Oral Health Impact Scale (ECOHIS) and Family Impact Scale (FIS), respectively. Students in grades 4-12 completed the Child Perceptions Questionnaire (CPQ8-10 in grades 4-5; CPQ11-14 in grades 6-12). All students were examined for fluorosis (Dean’s index) and caries experience (d2-3fs or D2-3MFS indices). OHRQoL scores (sum response codes) were analyzed for their association with fluorosis categories and sum of d2-3fs and D2-3MFS according to ordinary least squares regression with SAS procedures for multiple imputation and analysis of complex survey data. Differences in OHRQoL scores were evaluated against statistical and minimal important difference (MID) thresholds. Of 5,484 examined students, 71.8% had no fluorosis; 24.4%, questionable to very mild fluorosis; and 3.7%, mild, moderate, or severe fluorosis. Caries categories were as follows: none (43.1%), low (28.6%), and moderate to high (28.2%). No associations between fluorosis and any OHRQoL scales met statistical or MID thresholds. The difference (5.8 points) in unadjusted mean ECOHIS scores for the no-caries and moderate-to-high caries groups exceeded the MID estimate (2.7 points) for that scale. The difference in mean FIS scores (1.5 points) for the no-caries and moderate-to-high groups exceeded the MID value (1.2 points). The sum of d2-3fs and D2-3MFS scores was positively associated with CPQ11-14 (B = 0.240, p < .001), ECOHIS (B = 0.252, p ≤ .001), and FIS (B = 0.096, p ≤ .01) scores in ordinary least squares regression models. A child’s caries experience negatively affects OHRQoL, while fluorosis has little impact. PMID:25154834

  12. Effects of enamel fluorosis and dental caries on quality of life.

    PubMed

    Onoriobe, U; Rozier, R G; Cantrell, J; King, R S

    2014-10-01

    The objectives of this study were to determine the impact of enamel fluorosis and dental caries on oral health-related quality of life (OHRQoL) in North Carolina schoolchildren and their families. Students (n = 7,686) enrolled in 398 classrooms in grades K-12 were recruited for a onetime survey. Parents of students in grades K-3 and 4-12 completed the Early Childhood Oral Health Impact Scale (ECOHIS) and Family Impact Scale (FIS), respectively. Students in grades 4-12 completed the Child Perceptions Questionnaire (CPQ8-10 in grades 4-5; CPQ11-14 in grades 6-12). All students were examined for fluorosis (Dean's index) and caries experience (d2-3fs or D2-3MFS indices). OHRQoL scores (sum response codes) were analyzed for their association with fluorosis categories and sum of d2-3fs and D2-3MFS according to ordinary least squares regression with SAS procedures for multiple imputation and analysis of complex survey data. Differences in OHRQoL scores were evaluated against statistical and minimal important difference (MID) thresholds. Of 5,484 examined students, 71.8% had no fluorosis; 24.4%, questionable to very mild fluorosis; and 3.7%, mild, moderate, or severe fluorosis. Caries categories were as follows: none (43.1%), low (28.6%), and moderate to high (28.2%). No associations between fluorosis and any OHRQoL scales met statistical or MID thresholds. The difference (5.8 points) in unadjusted mean ECOHIS scores for the no-caries and moderate-to-high caries groups exceeded the MID estimate (2.7 points) for that scale. The difference in mean FIS scores (1.5 points) for the no-caries and moderate-to-high groups exceeded the MID value (1.2 points). The sum of d2-3fs and D2-3MFS scores was positively associated with CPQ11-14 (B = 0.240, p < .001), ECOHIS (B = 0.252, p ≤ .001), and FIS (B = 0.096, p ≤ .01) scores in ordinary least squares regression models. A child's caries experience negatively affects OHRQoL, while fluorosis has little impact.

  13. Remineralization of human natural caries and artificial caries-like lesions with an experimental whisker-reinforced ART-composite

    PubMed Central

    Yang, Bin; Flaim, Glenn; Dickens, Sabine H.

    2011-01-01

    To compare the remineralization of human natural caries and artificial caries-like dentin lesions from a novel whisker-reinforced experimental composite resin to a resin-modified glass ionomer cement (RM-GIC) as control. Ten molars with moderate natural dentin caries were prepared (N). Artificial caries-like dentin lesions were prepared in occlusal dentin of ten caries-free molars and demineralized at pH=4.3 for 48 h (A). The cavities were restored with ART-composite or RM-GIC. All restored teeth were sliced into 120-μm sections. Transverse microradiography combined with digital image analysis was performed to analyze the change in mineral density at the same position of the specimens before, after 4 weeks and 8 weeks remineralization/demineralization treatment. The mean percent remineralization ± standard deviation after 4 weeks and 8 weeks are: N: ART-composite: 27±9, 46±14; RM-GIC: 18±6, 36±11; A: ART-composite: 48±9, 66±11; RM-GIC: 50±13, 62±11. For the remineralization of natural caries, there was a significant difference between ART-composite and RM-GIC (p<0.05). For both restoratives there were significant differences between remineralization of natural and artificial caries (p<0.001). ART-composite and RM-GIC remineralized natural and artificial caries differently most likely due to differences in microstructure and composition of caries dentin. PMID:21232637

  14. Conservative approach for a clinical resolution of enamel white spot lesions.

    PubMed

    Nahsan, Flavia Pardo Salata; da Silva, Luciana Mendonça; Baseggio, Wagner; Franco, Eduardo Batista; Francisconi, Paulo Afonso Silveira; Mondelli, Rafael Francisco Lia; Wang, Linda

    2011-05-01

    Enamel white spot lesions in anterior teeth that compromise esthetics are common. Microabrasion is indicated, since it affects enamel superficially. An acid-abrasive slurry with 37% phosphoric acid with pumice was used on the enamel for a controlled time period. Home bleaching with hydrogen peroxide was then used, further improving the final result. The method is safe, easy, and conservative and provides good esthetic results.

  15. Microstructure and mechanical changes induced by Q-Switched pulse laser on human enamel with aim of caries prevention

    NASA Astrophysics Data System (ADS)

    Apsari, R.; Pratomo, D. A.; Hikmawati, D.; Bidin, N.

    2016-03-01

    This study was conducted to determine the effect of Q-Switched Nd: YAG laser energy dose to human enamel caries. The specifications of Q-Switched Nd: YAG laser as followed: wavelength of 1064 nm and 6 ns pulse width. Caries enamel samples taken from human teeth molars of 17-35 ages and the type of media caries. Energy doses used in this study were 723.65 mJ/cm2, 767.72 mJ/cm2, and 1065.515 mJ/cm2; 5 Hz repetition rate, and 20 second exposure time. Samples characterized the surface morphology and the percentage of constituent elements, especially calcium/phosphorus (Ca/P) with FESEM-EDAX. The fraction volume and crystallinity percentage of hydroxyapatite (HA) with XRD and hardness value using Vickers Microhardness Test. The results indicated that exposure of Q-Switched Nd:YAG laser on enamel caries resulting cracks, holes, and melt due to plasma production effects in the surface. Plasma production effect also resulted in micro properties such as percentage of Ca/P was close to normal, the fraction volume and crystallinity percentage of HA went up but did not change the crystal structure (in terms of the lattice structure). The hardness value also rose as linear as exposure energy dose caused by phototermal effect. Based on the results, Q-Switched Nd:YAG laser can be used as contactless drill dental caries replacement candidate with the additional therapy effect such as localized caries in order to avoid the spread, the ratio of Ca/P approaching healthy teeth, the fraction volume and crystallinity percentage of HA rose and established stronger teeth with peak energy dose 1065.515 mJ/cm2.

  16. Micro-computed tomographic analysis of progression of artificial enamel lesions in primary and permanent teeth after resin infiltration.

    PubMed

    Ozgul, Betul Memis; Orhan, Kaan; Oz, Firdevs Tulga

    2015-09-01

    We investigated inhibition of lesion progression in artificial enamel lesions. Lesions were created on primary and permanent anterior teeth (n = 10 each) and were divided randomly into two groups with two windows: Group 1 (window A: resin infiltration; window B: negative control) and Group 2 (window A: resin infiltration + fluoride varnish; window B: fluoride varnish). After pH cycling, micro-computed tomography was used to analyze progression of lesion depth and changes in mineral density. Resin infiltration and resin infiltration + fluoride varnish significantly inhibited progression of lesion depth in primary teeth (P < 0.05). Inhibition of lesion depth progression in permanent teeth was significantly greater after treatment with resin infiltration + fluoride varnish than in the negative control (P < 0.05). Change in mineral density was smaller in the resin infiltration and resin infiltration + fluoride varnish groups; however, the difference was not significant for either group (P > 0.05). Resin infiltration is a promising method of inhibiting progression of caries lesions.

  17. CO2 laser irradiation enhances CaF2 formation and inhibits lesion progression on demineralized dental enamel-in vitro study.

    PubMed

    Zancopé, Bruna R; Rodrigues, Lívia P; Parisotto, Thais M; Steiner-Oliveira, Carolina; Rodrigues, Lidiany K A; Nobre-dos-Santos, Marinês

    2016-04-01

    This study evaluated if Carbon dioxide (CO2) (λ 10.6 μm) laser irradiation combined with acidulated phosphate fluoride gel application (APF gel) enhances "CaF2" uptake by demineralized enamel specimens (DES) and inhibits enamel lesion progression. Thus, two studies were conducted and DES were subjected to APF gel combined or not with CO2 laser irradiation (11.3 or 20.0 J/cm(2), 0.4 or 0.7 W) performed before, during, or after APF gel application. In study 1, 165 DES were allocated to 11 groups. Fluoride as "CaF2 like material" formed on enamel was determined in 100 DES (n = 10/group), and the surface morphologies of 50 specimens were evaluated by scanning electron microscopy (SEM) before and after "CaF2" extraction. In study 2, 165 DES (11 groups, n = 15), subjected to the same treatments as in study 1, were further subjected to a pH-cycling model to simulate a high cariogenic challenge. The progression of demineralization in DES was evaluated by cross-sectional microhardness and polarized light microscopy analyses. Laser at 11.3 J/cm(2) applied during APF gel application increased "CaF2" uptake on enamel surface. Laser irradiation and APF gel alone arrested the lesion progression compared with the control (p < 0.05). Areas of melting, fusion, and cracks were observed. CO2 laser irradiation, combined with a single APF application enhanced "CaF2" uptake on enamel surface and a synergistic effect was found. However, regarding the inhibition of caries lesion progression, no synergistic effect could be demonstrated. In conclusion, the results have shown that irradiation with specific laser parameters significantly enhanced CaF2 uptake by demineralized enamel and inhibited lesion progression.

  18. Ability of laser fluorescence device associated with fluorescent dyes in detecting and quantifying early smooth surface caries lesions.

    PubMed

    Mendes, Fausto Medeiros; de Oliveira, Elisabeth; de Faria, Dalva Lúcia Araújo; Nicolau, José

    2006-01-01

    A laser fluorescence (LF) device is a portable tool, but it does not measure minor mineral changes. Our in vitro study aim is to propose the association of an LF with two fluorescent dyes and to evaluate the performance in detecting and quantifying early demineralization. Artificial caries lesions are created in 40 primary canine teeth using a demineralizing solution (pH=4.8) for 12, 24, 48, and 96 h. LF measurements are performed with DIAGNOdent after demineralization in these samples and in 20 sound primary teeth. Measurements with LF with 0.2-mM tetrakis(N-methylpyridyl)porphyrin (LF TMPyP) and with 4-mM protoporphyrin IX (LF PPIX) are made. The amount of calcium loss is determined by atomic emission spectrometry. A correlation between LF and LF with dyes and mineral loss and receiver operating characteristics analysis are performed, as well as comparisons of sensitivity, specificity, and accuracy values. Significant correlation is obtained with LF TMPyP and mineral loss of lesions demineralized for 24, 48, and 96 h. Better performance is achieved with LF TMPyP for all parameters than with LF alone. LF PPIX does not present good results. In conclusion, LF TMPyP provides good performance in detecting and quantifying very early enamel caries lesions.

  19. Characterization of dentin, enamel, and carious lesions by a polarization-sensitive optical coherence tomography system

    NASA Astrophysics Data System (ADS)

    Chen, Yueli; Otis, Linda; Piao, Daqing; Zhu, Quing

    2005-04-01

    Enamel and dentin are the primary components of human teeth. Both of them have a strong polarization effect. We designed a polarization-sensitive optical coherence tomography (PSOCT) system to study the spatially resolved scattering and polarization phenomena of teeth. The system is constructed in free space to avoid the complexity of polarization control in fiber-based PSOCT. The structural features of enamel were evaluated in five human teeth that had no visible evidence of caries. The teeth were subsequently sectioned in mesial distal orientation and coronal orientation. Then the structural aspects of dentin were evaluated. OCT images were made of the mantel dentin near the dentin-enamel junction. Five teeth with interproximal and occlusal caries were also studied. With two channel and phase-retardation images, PSOCT provided better functional contrast and more detailed structural information than conventional OCT. For a better description of the measured PSOCT data, we classify these features by two types, i.e., the local textural features and the global structural features. This study indicates that PSOCT has the potential to be a powerful tool for research of dental formation and caries diagnosis.

  20. Biological factors in dental caries enamel structure and the caries process in the dynamic process of demineralization and remineralization (part 2).

    PubMed

    Hicks, John; Garcia-Godoy, Franklin; Flaitz, Catherine

    2004-01-01

    Dental caries is a complex disease process that afflicts a large proportion of the world's population, regardless of gender, age and ethnicity, although it does tend to affect more indivduals with a low socioeconomic status to a greater extent. The physicochemical properties of the mineral comprising the tooth surface and subsurface modulate the development, arrestment and remineralization of dental caries. Post-eruption maturation of enamel surfaces and exposed root surfaces is important in order for more susceptible mineral phases to be modified by incorporation of soluble fluoride from the plaque into dental hydroxyapatite. The chemical reactions that occur during acidic conditions when tooth mineral dissolves (critical pH) are determined by the supersaturation of calcium and phosphate within plaque and saliva, as well as if fluoride is present.

  1. Determinant Factors of Untreated Dental Caries and Lesion Activity in Preschool Children Using ICDAS.

    PubMed

    Pinto-Sarmento, Tássia Cristina de Almeida; Abreu, Mauro Henrique; Gomes, Monalisa Cesarino; Costa, Edja Maria Melo de Brito; Martins, Carolina Castro; Granville-Garcia, Ana Flávia; Paiva, Saul Martins

    2016-01-01

    The aim of the present study was to investigate determinant factors associated with the presence of dental caries and lesion activity in preschool children. A population-based, cross-sectional study was carried out with 843 children of aged three to five years enrolled at public and private preschools in the city of Campina Grande, Brazil. A questionnaire addressing socio-demographic data and oral health care was self-administered by parents/caregivers. Three dentists previously calibrated examined the children for the diagnosis of dental caries and lesion activity using the International Caries Detection and Assessment System (ICDAS). Nutritional status was evaluated based on the body mass index. Logistic regression analysis for complex samples was performed (α = 5%). The prevalence of dental caries was 66.3%. Among the children with caries, 88.0% had active lesions. Dental caries was more prevalent in girls (OR = 1.53, 95%CI: 1.05-2.23), in children from families with a monthly household income ≤US$312.50 (OR = 2.38, 95%CI: 1.65-3.43) and those whose mothers had up to eight years of schooling (OR = 1.55, 95%CI: 1.07-2.23). Lesion activity was significantly associated with mother's schooling ≤ 8 years (OR = 2.15, 95%CI: 1.15-4.00). The prevalence rates of dental caries and lesion activity were high and mainly associated with a lower socioeconomic status and mother's schooling.

  2. Physical, chemical, and histologic changes in dentin caries lesions of primary teeth induced by regular use of polyol chewing gums.

    PubMed

    Mäkinen, K K; Chiego, D J; Allen, P; Bennett, C; Isotupa, K P; Tiekso, J; Mäkinen, P L

    1998-06-01

    A previous clinical trial showed that long-term use of saliva-stimulating polyol (xylitol and sorbitol) chewing gums was associated with arrest of dental caries in young subjects. After a 20-22-month intervention (when the subjects were 8 years old), a total of 23 primary teeth with extensive dentin caries lesions whose surface in clinical examination was found to be totally rehardened (remineralized) could be removed because the teeth were near their physiologic exfoliation time. These teeth were subjected to histologic, microhardness, and electron microscopic tests. The majority of the specimens had been remineralized from the surface by a non-cellular-mediated process within the remaining collapsed, organic extracellular matrix associated with the remaining dentinal surface. Many of the underlying dentinal tubules were filled with a matrix that had been subsequently mineralized. Dental microanalyses showed that the topmost (outer) 20-microm-thick rehardened layer of the lesions exhibited the highest Ca:P ratio, which leveled off at a depth of approximately 150 microm. The rehardened surface layer (normally <0.1 mm in thickness) was significantly (P < 0.001) harder than sound dentin and nearly as hard as sound enamel. Although the main source of the mineral present in the rehardened layer was most likely of salivary origin, some extracellular remineralization was probably mediated by odontoblasts. The results complete the dinical diagnoses of the original trial and suggest that regular use of polyol chewing gums may induce changes in dentin caries lesions, which in histologic and physiochemical studies show typical characteristics of rehardening and mineralization.

  3. In situ remineralization of subsurface enamel lesion after the use of a fluoride chewing gum.

    PubMed

    Lamb, W J; Corpron, R E; More, F G; Beltran, E D; Strachan, D S; Kowalski, C J

    1993-01-01

    In situ remineralization of early enamel lesions by a fluoride chewing gum was studied. Human enamel specimens with subsurface lesions were mounted in removable lower appliances for 6 adults. Subjects used a F-free dentifrice 3x/day and chewed five sticks/day for the F gum group (0.1 mg F/stick) or five sticks of sugarless gum. No gum was chewed for controls. Surface microhardness was performed on: (1) sound enamel; (2) lesions; (3) after intraoral exposure, and (4) after acid-resistance testing (ART). Separate specimens were etched and measured for F uptake and image analyses on microradiographs were performed for all regimens. delta Z values were calculated and converted to percent of mineralization. Values for F gum were significantly higher (p > 0.05) than non-F gum and controls for ART, percent remineralization, and F uptake up to 70 microns depth.

  4. Enamel demineralization with two forms of archwire ligation investigated using an in situ caries model--a pilot study.

    PubMed

    Gameiro, Gustavo Hauber; Nouer, Darcy Flávio; Cenci, Maximiliano Sérgio; Cury, Jaime Aparecido

    2009-10-01

    A modified in situ model to assess enamel demineralization around orthodontic devices was developed and a pilot study was conducted to evaluate two types of archwire ligation. Enamel blocks were placed in palatal removable appliances where orthodontic brackets were bonded. The brackets on one side of the appliance were ligated with elastomeric rings and those on the other side with stainless steel wires. Four volunteers (two males, two females), mean age 27 years, wore the appliances for 14 days during which time a 20 per cent sucrose solution was dripped eight times a day onto the enamel blocks. The biofilm formed around the brackets was collected for microbiological analyses and the mineral loss around the brackets was determined by cross-sectional microhardness measurement. The ligatures evaluated did not differ significantly from each other regarding biofilm weight, total bacteria, total streptococci, mutans streptococci, or lactobacilli counts (P > 0.05, Wilcoxon paired test). Enamel demineralization was also not different around the brackets for the different ligation methods (P > 0.05, split-split-plot analysis of variance). However, a statistical power analysis based on the data showed a trend to higher demineralization around brackets ligated with elastomeric rings. The developed modified in situ model may be suitable to assess the caries potential of clinical procedures used in orthodontic treatment.

  5. Prevalence of dental caries and enamel defects in the primary dentition of Antiguan pre-school children aged 3-4 years including an assessment of their habits.

    PubMed

    Vignarajah, S; Williams, G A

    1992-12-01

    In 1989 a national survey was carried out on children aged 3 to 4 years attending nursery schools, to investigate the prevalence of caries experience, nursing bottle caries and enamel defects in the primary dentition, and these children's dentally related habits. In the first part of the study, examination of 482 Antiguan children showed that the dmft and dmfs values were 0.80 and 1.26 respectively, and that 77 per cent of the children were caries free; 4.6 per cent of children had nursing bottle caries; and enamel defects occurred in 24 per cent of children. No significant difference was found in oral health between urban and rural samples. In the second part, which was an interview survey, habits such as thumb sucking (13 per cent), not brushing their teeth (3 per cent), and swallowing fluoride toothpaste (13 per cent) were found among 369 children. In the third (a questionnaire) survey, a response rate of 63 per cent was obtained. Significantly more of the children with nursing bottle caries (78.6 per cent) had the habit of sleeping with a feeding bottle than occurred in caries free children (25.6 per cent), but there was no difference in the infant feeding pattern. The children with enamel defects were breast fed for a shorter period and had an earlier introduction to bottle feeding, compared with children without enamel defects. In the final part of the survey, an assessment of snack eating habits at school, a 58 per cent response rate was achieved. The majority of children often brought healthier snacks, together with daily sugar-rich drinks. Significantly more caries free children brought sugary snacks less frequently than children with caries experience.

  6. Polarization sensitive optical coherence tomography for quantifying the severity of natural caries lesions on occlusal surfaces

    NASA Astrophysics Data System (ADS)

    Fried, Daniel; Ngaotheppitak, Patara; Darling, Cynthia L.; Ho, Chi M.

    2007-02-01

    Previous studies have demonstrated that Polarization Sensitive Optical Coherence Tomography (PS-OCT) can be used to image early dental caries. The purpose of this study was to compare the measured integrated reflectivity of natural caries lesions with the mineral loss measured using digital microradiography in order to determine if PS-OCT can be used as a nondestructive in vivo method to measure the severity of dental decay in the important occlusal surfaces. A PS-OCT system operating at 1310-nm was used to acquire polarization resolved images of natural caries lesions on the occlusal surfaces of extracted teeth. The integrated reflectivity from lesion areas was compared to the integrated mineral loss from the same lesion area measured using digital microradiography. There was a strong correlation between the integrated mineral loss of the caries lesion measured using high resolution digital microradiography and the integrated reflectivity in the perpendicular polarization axis of the PS-OCT system demonstrating the potential for this method to nondestructively monitor the severity of caries lesion in the occlusal pit and fissure where most new decay is found. Although we find these results encouraging, we desire a higher correlation between the integrated mineral loss and the integrated reflectivity and we believe a higher correlation is attainable with better matching of the PS-OCT scans and the histological thin sections.

  7. Enhancing the detection of hidden occlusal caries lesions with OCT using high index liquids

    NASA Astrophysics Data System (ADS)

    Kang, Hobin; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    In a previous study, we investigated the influence of several high refractive index fluids on the performance of polarization sensitive optical coherence tomography (PS-OCT). That study showed that these liquids can increase the effective imaging depth and lesion contrast. Other in vitro and in vivo studies have shown that OCT can be used to show whether occlusal lesions have penetrated to the dentinal-enamel junction (DEJ) and spread laterally under the enamel. The purpose of this study was to determine if high index fluids can enhance the ability of OCT to detect hidden occlusal lesions and show if these lesions have penetrated through the enamel into the underlying dentin. Ten extracted teeth with occlusal lesions were imaged using OCT after the application of water, glycerol, BABB (33% Benzyl Alcohol + 67% Benzyl Benzoate) and a Cargille Liquid (Cedar Grove, NJ) (hydrogenated terphenyl 1- bromo-naphthalene) with a refractive index of 1.61. The intensity of the reflectance from the underlying lesion area for each sample was compared with the reflectance of the sound tooth surface for each fluid. The use of high index fluids significantly (P< 0.0001) increased the reflectivity of subsurface occlusal lesions under the surrounding sound enamel.

  8. Effect of Lesion Baseline Severity and Mineral Distribution on Remineralization and Progression of Human and Bovine Dentin Caries Lesions.

    PubMed

    Lippert, Frank; Churchley, David; Lynch, Richard J

    2015-01-01

    The aims of this laboratory study were to compare the effects of lesion baseline severity, mineral distribution and substrate on remineralization and progression of caries lesions created in root dentin. Lesions were formed in dentin specimens prepared from human and bovine dentin using three protocols, each utilizing three demineralization periods to create lesions of different mineral distributions (subsurface, moderate softening, extreme softening) and severity within each lesion type. Lesions were then either remineralized or demineralized further and analyzed using transverse microradiography. At lesion baseline, no differences were found between human and bovine dentin for integrated mineral loss (x0394;Z). Differences in mineral distribution between lesion types were apparent. Human dentin lesions were more prone to secondary demineralization (x0394;x0394;Z) than bovine dentin lesions, although there were no differences in x0394;L. Likewise, smaller lesions were more susceptible to secondary demineralization than larger ones. Subsurface lesions were more acid-resistant than moderately and extremely softened lesions. After remineralization, differences between human and bovine dentin lesions were not apparent for x0394;x0394;Z although bovine dentin lesions showed greater reduction in lesion depth L. For lesion types, responsiveness to remineralization (x0394;x0394;Z) was in the order extremely softened>moderately softened>subsurface. More demineralized lesions exhibited greater remineralization than shallower ones. In summary, some differences exist between human and bovine dentin and their relative responsiveness to de- and remineralization. These differences, however, were overshadowed by the effects of lesion baseline mineral distribution and severity. Thus, bovine dentin appears to be a suitable substitute for human dentin in mechanistic root caries studies.

  9. Comparison of cross-sectional hardness and transverse microradiography of artificial carious enamel lesions induced by different demineralising solutions and gels.

    PubMed

    Magalhães, A C; Moron, B M; Comar, L P; Wiegand, A; Buchalla, W; Buzalaf, M A R

    2009-01-01

    The aims of this study were: (1) to correlate surface (SH) and cross-sectional hardness (CSH) with microradiographic parameters of artificial enamel lesions; (2) to compare lesions prepared by different protocols. Fifty bovine enamel specimens were allocated by stratified randomisation according to their initial SH values to five groups and lesions produced by different methods: MC gel (methylcellulose gel/lactic acid, pH 4.6, 14 days); PA gel (polyacrylic acid/lactic acid/hydroxyapatite, pH 4.8, 16 h); MHDP (undersaturated lactate buffer/methyl diphosphonate, pH 5.0, 6 days); buffer (undersaturated acetate buffer/fluoride, pH 5.0, 16 h), and pH cycling (7 days). SH of the lesions (SH(1)) was measured. The specimens were longitudinally sectioned and transverse microradiography (TMR) and CSH measured at 10- to 220-microm depth from the surface. Overall, there was a medium correlation but non-linear and variable relationship between mineral content and radicalCSH. radicalSH(1) was weakly to moderately correlated with surface layer properties, weakly correlated with lesion depth but uncorrelated with integrated mineral loss. MHDP lesions showed the highest subsurface mineral loss, followed by pH cycling, buffer, PA gel and MC gel lesions. The conclusions were: (1) CSH, as an alternative to TMR, does not estimate mineral content very accurately, but gives information about mechanical properties of lesions; (2) SH should not be used to analyse lesions; (3) artificial caries lesions produced by the protocols differ, especially considering the method of analysis.

  10. Determinant Factors of Untreated Dental Caries and Lesion Activity in Preschool Children Using ICDAS

    PubMed Central

    Pinto-Sarmento, Tássia Cristina de Almeida; Abreu, Mauro Henrique; Gomes, Monalisa Cesarino; Costa, Edja Maria Melo de Brito; Martins, Carolina Castro; Granville-Garcia, Ana Flávia; Paiva, Saul Martins

    2016-01-01

    The aim of the present study was to investigate determinant factors associated with the presence of dental caries and lesion activity in preschool children. A population-based, cross-sectional study was carried out with 843 children of aged three to five years enrolled at public and private preschools in the city of Campina Grande, Brazil. A questionnaire addressing socio-demographic data and oral health care was self-administered by parents/caregivers. Three dentists previously calibrated examined the children for the diagnosis of dental caries and lesion activity using the International Caries Detection and Assessment System (ICDAS). Nutritional status was evaluated based on the body mass index. Logistic regression analysis for complex samples was performed (α = 5%). The prevalence of dental caries was 66.3%. Among the children with caries, 88.0% had active lesions. Dental caries was more prevalent in girls (OR = 1.53, 95%CI: 1.05–2.23), in children from families with a monthly household income ≤US$312.50 (OR = 2.38, 95%CI: 1.65–3.43) and those whose mothers had up to eight years of schooling (OR = 1.55, 95%CI: 1.07–2.23). Lesion activity was significantly associated with mother’s schooling ≤ 8 years (OR = 2.15, 95%CI: 1.15–4.00). The prevalence rates of dental caries and lesion activity were high and mainly associated with a lower socioeconomic status and mother’s schooling. PMID:26900846

  11. Occlusal caries detection using polarized Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Ionita, I.; Bulou, A.

    2008-02-01

    The tooth enamel, because of its hydroxyapatite composition, must present a Raman spectrum with strong polarization anisotropy. Carious lesions of the enamel will produce an alteration of local symmetry and will increase much more scattering of light. This will reduce the anisotropy of the Raman spectra. Because of the difference between high sensitivity to polarization of the 959 cm -1 Raman peak in sound enamel and low sensitivity in carried enamel, Raman polarized spectroscopy could be a useful method to early detect teeth caries.

  12. Optical quantification of caries-like lesions in vitro by use of a fluorescent dye

    SciTech Connect

    Van de Rijke, J.W.; Ten Bosch, J.J. )

    1990-05-01

    An experimental method was developed for measurement of the fluorescence intensity of a dye that was introduced into caries-like lesions in vitro. A distinct pattern of change of fluorescence intensity with time appeared, displaying a plateau value and a peak value for each measurement. Both plateau and peak values showed a linear correlation with calcium loss, as measured with longitudinal microradiography. The correlation coefficients were r = 0.87 for plateau values and r = 0.89 for peak values. The difference in scattering by dry and wet caries lesions was also measured with the same equipment, which showed a linear correlation with calcium loss of r = -0.53.

  13. Molecular and structural evaluation of dentin caries-like lesions produced by different artificial models.

    PubMed

    Pacheco, Larissa Ferreira; Banzi, Éfani Caroline de Freitas; Rodrigues, Eliana; Soares, Luís Eduardo Silva; Pascon, Fernanda Miori; Correr-Sobrinho, Lourenço; Puppin-Rontani, Regina Maria

    2013-01-01

    This study evaluated structural and molecular issues of dentin caries-like lesions produced by different artificial models (ACL) compared with natural caries lesions (NCL). One hundred twenty-four sound occlusal dentin blocks and 47 carious blocks were obtained and surface hardness was analyzed (SH1). They were assigned to groups according to ACL: GB: Biological; GC: Chemical; GIS: In situ; GNC: natural caries (control). Blocks from groups 1, 2 and 3 were submitted to caries lesion induction. NCL and ACL blocks were submitted to surface hardness (SH 2), FT-Raman and µEDXRF analysis. All blocks were longitudinally sectioned and one of the halves was submitted to cross-sectional hardness (CSH) and the other to SEM analysis. SH1 and SH2 data were submitted to t test (unpaired and paired, respectively), CSH and SEM data to two-way and one-way ANOVA respectively, and Tukey and t tests, respectively (p<0.05). Data from FT-Raman/µEDXRF were submitted to one-way ANOVA and Dunnett multiple-comparisons test (a=0.05). GB and GNC showed lowest SH2 values that were significantly different from GC and GIS. Regarding CSH, GB and GNC showed no significant difference between them. SEM showed similar caries lesion depth for GB and GNC, being significantly higher than for GC and GIS. µEDXRF showed similar values of calcium and phosphate for GB and GNC; GNC values were significantly different from GIS. No significant difference was found among the groups concerning phosphate, carbonate and CH bonds values. For collagen type I, GC values were significantly different compared to other groups. It may be concluded that caries-like lesions produced by GB were the closest model to NCL.

  14. Undermining of enamel as a mechanism of abfraction lesion formation: a finite element study.

    PubMed

    Rees, J S; Hammadeh, M

    2004-08-01

    Many workers have suggested that abfraction lesion formation is caused by the physical overloading of enamel. However, an alternative mechanism, involving undermining of the cervical enamel along the amelodentinal junction (ADJ), may be a more realistic explanation. The aim of this study was to examine what effect undermining of the buccal cervical enamel would have on the stress distribution in upper teeth. Two-dimensional plain strain finite element meshes of an upper incisor, canine and first premolar and the supporting periodontal ligament and alveolar bone were developed. Each tooth was loaded with an oblique 100 N load, and the nodal maximum principal stresses (MPS) along a buccal horizontal sampling plane 1.1 mm above the amelo-cemental junction was measured. A discontinuity between the cervical enamel and dentine elements was then introduced (0.1 mm wide) using gap elements. The vertical extent of this defect varied from 0.1 to 0.5 mm. The value of the MPS varied from 1.8 to 209 Mpa, and the lowest values were found for the intact teeth (range 0.6-30.3 MPa). The discontinuity caused a dramatic increase in the numerical values of the MPS, and in many instances these exceeded the known failure stress for enamel.

  15. Enamel and dentine demineralization by a combination of starch and sucrose in a biofilm - caries model.

    PubMed

    Botelho, Juliana Nunes; Villegas-Salinas, Mario; Troncoso-Gajardo, Pía; Giacaman, Rodrigo Andrés; Cury, Jaime Aparecido

    2016-05-20

    Sucrose is the most cariogenic dietary carbohydrate and starch is considered non-cariogenic for enamel and moderately cariogenic for dentine. However, the cariogenicity of the combination of starch and sucrose remains unclear. The aim of this study was to evaluate the effect of this combination on Streptococcus mutans biofilm composition and enamel and dentine demineralization. Biofilms of S. mutans UA159 were grown on saliva-coated enamel and dentine slabs in culture medium containing 10% saliva. They were exposed (8 times/day) to one of the following treatments: 0.9% NaCl (negative control), 1% starch, 10% sucrose, or 1% starch and 10% sucrose (starch + sucrose). To simulate the effect of human salivary amylase on the starch metabolization, the biofilms were pretreated with saliva before each treatment and saliva was also added to the culture medium. Acidogenicity of the biofilm was estimated by evaluating (2 times/day) the culture medium pH. After 4 (dentine) or 5 (enamel) days of growth, biofilms (n = 9) were individually collected, and the biomass, viable microorganism count, and polysaccharide content were quantified. Dentine and enamel demineralization was assessed by determining the percentage of surface hardness loss. Biofilms exposed to starch + sucrose were more acidogenic and caused higher demineralization (p < 0.0001) on either enamel or dentine than those exposed to each carbohydrate alone. The findings suggest that starch increases the cariogenic potential of sucrose.

  16. Enamel Formation Genes Influence Enamel Microhardness Before and After Cariogenic Challenge

    PubMed Central

    Shimizu, Takehiko; Ho, Bao; Deeley, Kathleen; Briseño-Ruiz, Jessica; Faraco, Italo M.; Schupack, Brett I.; Brancher, João A.; Pecharki, Giovana D.; Küchler, Erika C.; Tannure, Patricia N.; Lips, Andrea; Vieira, Thays C. S.; Patir, Asli; Yildirim, Mine; Poletta, Fernando A.; Mereb, Juan C.; Resick, Judith M.; Brandon, Carla A.; Orioli, Iêda M.; Castilla, Eduardo E.; Marazita, Mary L.; Seymen, Figen; Costa, Marcelo C.; Granjeiro, José M.; Trevilatto, Paula C.; Vieira, Alexandre R.

    2012-01-01

    There is evidence for a genetic component in caries susceptibility, and studies in humans have suggested that variation in enamel formation genes may contribute to caries. For the present study, we used DNA samples collected from 1,831 individuals from various population data sets. Single nucleotide polymorphism markers were genotyped in selected genes (ameloblastin, amelogenin, enamelin, tuftelin, and tuftelin interacting protein 11) that influence enamel formation. Allele and genotype frequencies were compared between groups with distinct caries experience. Associations with caries experience can be detected but they are not necessarily replicated in all population groups and the most expressive results was for a marker in AMELX (p = 0.0007). To help interpret these results, we evaluated if enamel microhardness changes under simulated cariogenic challenges are associated with genetic variations in these same genes. After creating an artificial caries lesion, associations could be seen between genetic variation in TUFT1 (p = 0.006) and TUIP11 (p = 0.0006) with enamel microhardness. Our results suggest that the influence of genetic variation of enamel formation genes may influence the dynamic interactions between the enamel surface and the oral cavity. PMID:23028741

  17. Saliva substitutes in combination with highly concentrated fluorides and brushing: in vitro effects on enamel subsurface lesions.

    PubMed

    Tschoppe, P; Siegel, A; Meyer-Lueckel, H

    2010-01-01

    Hyposalivation is often associated with high caries activity, in particular in patients undergoing irradiation in the head/neck area. Besides the use of saliva substitutes to relieve the oral symptoms, daily application of fluoride gels or toothpaste (5,000 μg F⁻/g) is recommended for caries prevention. The aim of this study was to evaluate potentially remineralising effects of these fluoride agents in combination with saliva substitutes on enamel subsurface lesions. Demineralised bovine specimens were either stored in mineral water [control; saturation with respect to octacalcium phosphate (S(OCP)): 0.8], a demineralising saliva substitute (Glandosane; S(OCP): 0.3) or in a modified (with respect to S(OCP)) saliva substitute [Saliva natura (SN); S(OCP): 1.9] for 5 weeks (37°C). The following treatments were applied twice daily (11-13/group): no treatment (0), ProSchmelz fluoride gel (PS; 10 min application), Duraphat toothpaste (DP; 10 s; brushing with toothpaste/storage solution slurry), combination of DP+PS. Mineral parameters before/after storage were evaluated from microradiographs. Storage in Glandosane led to significant demineralisation (p < 0.05; paired t test), whereas additional use of fluoride agents neutralised the demineralising effect (p > 0.05). Storage in water alone resulted in no changes in mineral parameters (p > 0.05), whereas in combination with fluorides remineralisation could be shown (p < 0.05). For SN alone, remineralisation was observed (p < 0.05), but no additional beneficial effects of fluorides were detected. Under the conditions chosen, the fluoride agents reduce the demineralising effects of Glandosane and promote the remineralisation of specimens stored in water. Remineralising effects of SN could not be enhanced by the fluorides.

  18. Restorative Treatment Thresholds for Occlusal Primary Caries by Dentists in “The Dental Practice-Based Research Network”

    PubMed Central

    Gordan, Valeria V; Bader, James D; Garvan, Cynthia W; Richman, Joshua S; Qvist, Vibeke; Fellows, Jeffrey L; Rindal, D. Brad; Gilbert, Gregg H

    2010-01-01

    Objectives (1) Quantify at which carious lesion depths dentists intervene surgically for cases of varying caries penetration and caries risk; (2) Identify characteristics that are associated with surgical intervention. Methods Dentists in a practice-based research network who reported doing at least some restorative dentistry were surveyed. Dentists were asked to indicate whether they would surgically intervene in a series of cases depicting occlusal caries. Each case included a photograph of an occlusal surface displaying typical characteristics of caries penetration, and a written description of a patient at a specific level of caries risk. Using logistic regression, we analyzed associations of surgical treatment with dentist and practice characteristics, and patient caries risk levels. Results 519 DPBRN practitioner-investigators responded, of whom 63% indicated that they would surgically restore lesions located on inner enamel surfaces, and 90% of lesions located in outer dentin surfaces in a low caries risk individual. Regarding individuals at high caries risk, 77% reported that they would surgically restore inner enamel lesions and 94% reported restoring lesions located on the outer dentin surface. Dentists who did not assess caries risk were more likely to intervene on dentin lesions (p=.004). Practitioner-investigators who were in private practice were significantly more likely to intervene surgically on enamel lesions, compared to dentists from large group practices (p<.001). Conclusion Most dentists chose to provide some treatment to lesions that were within the enamel surface. Decisions to intervene surgically in the caries process differ by caries lesion depth, patient caries risk, assessment of caries risk, type of practice model, and percent of patients who self-pay. PMID:20123876

  19. Prevalence and extent of dental caries, dental fluorosis, and developmental enamel defects in Lithuanian teenage populations with different fluoride exposures.

    PubMed

    Machiulskiene, Vita; Baelum, Vibeke; Fejerskov, Ole; Nyvad, Bente

    2009-04-01

    The aim of this study was to describe the pattern of dental caries, dental fluorosis, and developmental defects of non-fluoride origin in Lithuanian children born and raised in regions with 1.1 ppm (1.1 mg/l F) and 0.3 ppm (0.3 mg/l F) water fluoride levels, respectively. All permanent surfaces/teeth of 300 teenagers were examined for dental caries, dental fluorosis, and non-fluoride developmental defects. The caries prevalence of the study population was 100%. The mean number of decayed surfaces (DS) differed only slightly and statistically insignificantly between the '1.1 ppm fluoride' and '0.3 ppm fluoride' groups (19.6 and 18.1, respectively). However, a greater number of inactive lesions and fewer fillings were found in the '1.1 ppm fluoride' group than in the '0.3 ppm fluoride' group (mean difference 1.18 and -2.80, respectively). The prevalence of dental fluorosis was 45% and 21%, respectively; the prevalence of non-fluoride opacities was 8% and 19%, respectively; and the prevalence of hypoplasia was 12% and 16%, respectively, in the '1.1 ppm fluoride' and '0.3 ppm fluoride' groups. Higher caries levels were noted in children with no fluorosis compared to those with fluorosis recorded (mean DS difference, 3.43). The results lend support to the hypothesis that the presence of fluoride in the oral environment promotes lesion arrest rather than inhibiting the initiation of new lesions.

  20. Enamel subsurface lesion remineralisation with casein phosphopeptide stabilised solutions of calcium, phosphate and fluoride.

    PubMed

    Cochrane, N J; Saranathan, S; Cai, F; Cross, K J; Reynolds, E C

    2008-01-01

    Casein phosphopeptide stabilised amorphous calcium phosphate (CPP-ACP) and amorphous calcium fluoride phosphate (CPP-ACFP) solutions have been shown to remineralise enamel subsurface lesions. The aim of this study was to determine the effect of ion composition of CPP-ACP and CPP-ACFP solutions on enamel subsurface lesion remineralisation in vitro. CPP-bound and free calcium, phosphate and fluoride ion concentrations in the solutions were determined after ultrafiltration. The ion activities of the free ion species present were calculated using an iterative computational program. The mineral deposited in the subsurface lesions was analysed using transverse microradiography and electron microprobe. CPP was found to stabilise high concentrations of calcium, phosphate and fluoride ions at all pH values (7.0-4.5). Remineralisation of the subsurface lesions was observed at all pH values tested with a maximum at pH 5.5. The CPP-ACFP solutions produced greater remineralisation than the CPP-ACP solutions at pH 5.5 and below. The mineral formed in the subsurface lesions was consistent with hydroxyapatite and fluorapatite for remineralisation with CPP-ACP and CPP-ACFP, respectively. The activity gradient of the neutral ion pair CaHPO(4)(0) into the lesion was significantly correlated with remineralisation and together with HF(0) were identified as important species for diffusion.

  1. Actinomyces spp. gene expression in root caries lesions

    PubMed Central

    Dame-Teixeira, Naile; Parolo, Clarissa Cavalcanti Fatturi; Maltz, Marisa; Tugnait, Aradhna; Devine, Deirdre; Do, Thuy

    2016-01-01

    Background The studies of the distribution of Actinomyces spp. on carious and non-carious root surfaces have not been able to confirm the association of these bacteria with root caries, although they were extensively implicated as a prime suspect in root caries. Objective The aim of this study was to observe the gene expression of Actinomyces spp. in the microbiota of root surfaces with and without caries. Design The oral biofilms from exposed sound root surface (SRS; n=10) and active root caries (RC; n=30) samples were collected. The total bacterial RNA was extracted, and the mRNA was isolated. Samples with low RNA concentration were pooled, yielding a final sample size of SRS=10 and RC=9. Complementary DNA (cDNA) libraries were prepared and sequenced on an Illumina® HiSeq 2500 system. Sequence reads were mapped to eight Actinomyces genomes. Count data were normalized using DESeq2 to analyse differential gene expression applying the Benjamini-Hochberg correction (false discovery rate [FDR]<0.001). Results Actinomyces spp. had similar numbers of reads (Mann-Whitney U-test; p>0.05), except for Actinomyces OT178 (p=0.001) and Actinomyces gerencseriae (p=0.004), which had higher read counts in the SRS. Genes that code for stress proteins (clp, dnaK, and groEL), enzymes of glycolysis pathways (including enolase and phosphoenolpyruvate carboxykinase), adhesion (Type-2 fimbrial and collagen-binding protein), and cell growth (EF-Tu) were highly – but not differentially (p>0.001) – expressed in both groups. Genes with the most significant upregulation in RC were those coding for hypothetical proteins and uracil DNA glycosylase (p=2.61E-17). The gene with the most significant upregulation in SRS was a peptide ABC transporter substrate-binding protein (log2FC=−6.00, FDR=2.37E-05). Conclusion There were similar levels of Actinomyces gene expression in both sound and carious root biofilms. These bacteria can be commensal in root surface sites but may be cariogenic

  2. Dose-response effects of zinc and fluoride on caries lesion remineralization.

    PubMed

    Lippert, F

    2012-01-01

    The present mechanistic in vitro study aimed to investigate dose-response effects of zinc and fluoride on caries lesion remineralization and subsequent protection from demineralization. Artificial caries lesions were created using a methylcellulose acid gel system. Lesions were remineralized for 2 weeks using citrate-containing artificial saliva which was supplemented with zinc (0-153 μmol/l) and fluoride (1.1 or 52.6 μmol/l) in a 7 × 2 factorial design. Lesions were also remineralized in the absence of zinc and citrate, but in the presence of fluoride. After remineralization, all lesions were demineralized for 1 day under identical conditions. Changes in mineral distribution characteristics of caries lesions after remineralization and secondary demineralization were studied using transverse microradiography. At 1.1 μmol/l fluoride, zinc exhibited detrimental effects on remineralization in a dose-response manner and mainly by preventing remineralization near the lesion surface. At 52.6 μmol/l fluoride, zinc retarded remineralization only at the highest concentration tested. Zinc enhanced overall remineralization at 3.8-15.3 μmol/l. At 76.5 and less so at 153 μmol/l, zinc showed extensive remineralization of deeper parts within the lesions at the expense of remineralization near the surface. Citrate did not interfere with remineralization at 1.1 μmol/l fluoride, but enhanced remineralization at 52.6 μmol/l fluoride. Lesions exhibiting preferential remineralization in deeper parts showed higher mineral loss after secondary demineralization, suggesting the formation of more soluble mineral phases during remineralization. In summary, zinc and fluoride showed synergistic effects in enhancing lesion remineralization, however only at elevated fluoride concentrations.

  3. A microbiological study of primary root-caries lesions with different treatment needs.

    PubMed

    Beighton, D; Lynch, E; Heath, M R

    1993-03-01

    Samples of altered or carious dentin for microbiological culture were obtained from 301 primary root-caries lesions in 59 patients by means of a standardized sampling procedure. This involved the cleansing of each root surface of extraneous supragingival plaque by means of a hand-held toothbrush and distilled water and the collection of the sample with a sterile dental excavator passed through the entire vertical dimension of each lesion. The total number of colony-forming units (cfu) in each sample and the numbers of mutans streptococci (primarily Streptococcus mutans), lactobacilli, yeasts, and Gram-positive pleomorphic rods (GPPR) were determined. Individual bacterial counts were expressed as log10 (cfu per sample), as a percentage of the total number of bacteria per sample, and as a frequency of isolation from lesions with different clinical diagnostic criteria. Clinical measurements of each lesion were made for color, texture, position relative to the gingival margin, and treatment need. Lesions classified as soft yielded significantly more bacteria, mutans streptococci, lactobacilli, and GPPR than leathery lesions, which yielded more bacteria than hard lesions. Lesions were classified into 5 treatment categories: soft and restore, leathery and restore, leathery and debride of caries; leathery and treat therapeutically; and hard no treatment. The total numbers of bacteria, mutans streptococci, lactobacilli, GPPR, and yeasts decreased significantly with decreasing treatment need. The frequency of isolation of mutans streptococci, lactobacilli, and yeasts was significantly greater from lesions requiring restoration and from lesions situated within 1 mm of the gingival margin. We suggest that the majority of root caries is initiated adjacent to the gingival margin.

  4. Enamel lesion parameter correlations between polychromatic micro-CT and TMR.

    PubMed

    Hamba, H; Nikaido, T; Sadr, A; Nakashima, S; Tagami, J

    2012-06-01

    Transverse microradiography (TMR) is considered as the gold standard technique for the evaluation of enamel lesions. Micro-computed tomography (µCT) has the advantage of non-destructive measurements, but the beam-hardening effect with polychromatic x-rays is a major drawback. To date, no study has validated µCT against TMR. The objective of this study was to validate µCT measurements of enamel lesions under various x-ray conditions and software beam-hardening correction (BHC) against TMR. Human molars with natural white-spot lesions were scanned for 5 min by µCT at 100 kV in different conditions: 50 µA (0.5-mm Al filter), 165 µA (0.5-mm Al/0.3-mm Cu), and 200 µA (0.5-mm Al/0.4-mm Cu), with or without BHC. Grayscale values were converted into mineral density values using phantoms. Thin sections at the same positions were then prepared for TMR. Lesion depth (LD; µm) and mineral loss (ΔZ; vol%µm) were compared between µCT and TMR by Pearson's correlations. µCT measurements correlated well with TMR under all conditions (p < 0.001, r > 0.86 for LD and ΔZ), except for 0.5-mm Al without BHC (p > 0.05). Even without BHC, combined Al/Cu filters successfully reduced the beam-hardening effect. µCT can be used as a non-destructive alternative to TMR with comparable parameters for the study of enamel lesions.

  5. Remineralization of Demineralized Enamel via Calcium Phosphate Nanocomposite

    PubMed Central

    Weir, M.D.; Chow, L.C.; Xu, H.H.K.

    2012-01-01

    Secondary caries remains the main problem limiting the longevity of composite restorations. The objective of this study was to investigate the remineralization of demineralized human enamel in vitro via a nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP). NACP were synthesized by a spray-drying technique and incorporated into a dental resin. First, caries-like subsurface enamel lesions were created via an acidic solution. Then, NACP nanocomposite or a commercial fluoride-releasing control composite was placed on the demineralized enamel, along with control enamel without a composite. These specimens were then treated with a cyclic demineralization/remineralization regimen for 30 days. Quantitative microradiography showed typical enamel subsurface demineralization before cyclic demineralization/remineralization treatment, and significant remineralization in enamel under the NACP nanocomposite after the demineralization/remineralization treatment. The NACP nanocomposite had the highest enamel remineralization (mean ± SD; n = 6) of 21.8 ± 3.7%, significantly higher than the 5.7 ± 6.9% for fluoride-releasing composite (p < 0.05). The enamel group without composite had further demineralization of −26.1 ± 16.2%. In conclusion, a novel NACP nanocomposite was effective in remineralizing enamel lesions in vitro. Its enamel remineralization was 4-fold that of a fluoride-releasing composite control. Combined with the good mechanical and acid-neutralization properties reported earlier, the new NACP nanocomposite is promising for remineralization of demineralized tooth structures. PMID:22933607

  6. Effects of ozone and sodium hypochlorite on caries-like lesions in dentin.

    PubMed

    Zaura, E; Buijs, M J; ten Cate, J M

    2007-01-01

    The hypothesis that ozone promotes remineralization of dentinal lesions was tested in vitro. Artificial caries-like lesions in dentin were treated with ozone gas, with another potent oxidizer (sodium hypochlorite, NaOCl, 10%) or with water. The specimens were then remineralized and subsequently demineralized again. Mineral content was assessed by transverse microradiography. NaOCl-treated samples showed damaged surface and, after being remineralized, demineralized significantly more than water- or ozone-treated groups. No difference was found between ozone and water groups. The exposure to ozone had thus no effect on remineralization and subsequent demineralization of remineralized dentinal lesions.

  7. Dental Calculus Arrest of Dental Caries

    PubMed Central

    Keyes, Paul H.; Rams, Thomas E.

    2016-01-01

    Background An inverse relationship between dental calculus mineralization and dental caries demineralization on teeth has been noted in some studies. Dental calculus may even form superficial layers over existing dental caries and arrest their progression, but this phenomenon has been only rarely documented and infrequently considered in the field of Cariology. To further assess the occurrence of dental calculus arrest of dental caries, this study evaluated a large number of extracted human teeth for the presence and location of dental caries, dental calculus, and dental plaque biofilms. Materials and methods A total of 1,200 teeth were preserved in 10% buffered formal saline, and viewed while moist by a single experienced examiner using a research stereomicroscope at 15-25× magnification. Representative teeth were sectioned and photographed, and their dental plaque biofilms subjected to gram-stain examination with light microscopy at 100× magnification. Results Dental calculus was observed on 1,140 (95%) of the extracted human teeth, and no dental carious lesions were found underlying dental calculus-covered surfaces on 1,139 of these teeth. However, dental calculus arrest of dental caries was found on one (0.54%) of 187 evaluated teeth that presented with unrestored proximal enamel caries. On the distal surface of a maxillary premolar tooth, dental calculus mineralization filled the outer surface cavitation of an incipient dental caries lesion. The dental calculus-covered carious lesion extended only slightly into enamel, and exhibited a brown pigmentation characteristic of inactive or arrested dental caries. In contrast, the tooth's mesial surface, without a superficial layer of dental calculus, had a large carious lesion going through enamel and deep into dentin. Conclusions These observations further document the potential protective effects of dental calculus mineralization against dental caries. PMID:27446993

  8. Effect of acid-etching on remineralization of enamel white spot lesions.

    PubMed

    Al-Khateeb, S; Exterkate, R; Angmar-Månsson, B; ten Cate, J M; ten Cate, B

    2000-02-01

    This in vitro study aimed at investigating whether full remineralization would occur in white spot lesions when the surface porosity was increased by acid-etching. The effect of fluoride was also investigated. Enamel blocks with in vitro produced white spot lesions were used. Group A was exposed to a remineralizing solution only. In group B, the lesions were etched with 35% phosphoric acid for 30 s, then treated as in group A. Group C was treated as group A + daily treatment with a fluoride toothpaste slurry (1,000 ppm) for 5 min. Group D was treated as group B + the daily fluoride treatment of group C. The remineralization was measured weekly with Quantitative Light-induced Fluorescence during the experimental period. After 10 weeks of remineralization, mineral profiles were assessed with transverse microradiography. The enamel fluorescence was partly regained. There were significant differences in the lesion depth, mineral content at the surface layer, and integrated mineral loss between the groups. Addition of fluoride accelerated the remineralization only in the beginning; in later stages the process leveled out and even reached a plateau in all the groups. It was concluded that full remineralization was not achieved by etching, by the addition of fluoride, nor by the combination of both treatments in this in vitro study.

  9. Casein phosphopeptide-amorphous calcium phosphate and glass ionomer show distinct effects in the remineralization of proximal artificial caries lesion in situ.

    PubMed

    Thepyou, Rathapong; Chanmitkul, Wanvipa; Thanatvarakorn, Ornnicha; Hamba, Hidenori; Chob-Isara, Wanwalai; Trairatvorakul, Chutima; Tagami, Junji

    2013-01-01

    This study aimed to compare the ability of casein-phosphopeptide amorphous-calcium-phosphate (CPP-ACP) and glass-ionomer (GI) in remineralizing proximal artificial caries lesions (ACLs). Molar enamel-slabs were divided into: original-lesion control, intra-oral controls, and experimental (CPP-ACP or GI) groups. Specimens received ACLs and were bonded on subject maxillary first molars. After 4-weeks, mineral density (MD) was analyzed by μCT. Compared to control, CPP-ACP increased MD at 0-38/68-84 microns and the GI group had an increase at 0-68 microns, with a greater increase in MD compared to the CPP-ACP group from 0-53 microns. The mean percent remineralization (%R) showed differences between the GI, CPP-ACP groups and their paired controls. GI tended to increase remineralization more than CPP-ACP. In conclusion, CPP-ACP and GI demonstrated distinct remineralizing ability. GI induced greater remineralization in the superficial lesion, while CPP-ACP remineralized the lesion body. Their effects on percent remineralization and reducing lesion depth of proximal ACLs were similar.

  10. Assessment of natural enamel lesions with optical coherence tomography in comparison with microfocus x-ray computed tomography

    PubMed Central

    Espigares, Jorge; Sadr, Alireza; Hamba, Hidenori; Shimada, Yasushi; Otsuki, Masayuki; Tagami, Junji; Sumi, Yasunori

    2015-01-01

    Abstract. A technology to characterize early enamel lesions is needed in dentistry. Optical coherence tomography (OCT) is a noninvasive method that provides high-resolution cross-sectional images. The aim of this study is to compare OCT with microfocus x-ray computed tomography (μCT) for assessment of natural enamel lesions in vitro. Ten human teeth with visible white spot-like changes on the enamel smooth surface and no cavitation (ICDAS code 2) were subjected to imaging by μCT (SMX-100CT, Shimadzu) and 1300-nm swept-source OCT (Dental SS-OCT, Panasonic Health Care). In μCT, the lesions appeared as radiolucent dark areas, while in SS-OCT, they appeared as areas of increased signal intensity beneath the surface. An SS-OCT attenuation coefficient based on Beer–Lambert law could discriminate lesions from sound enamel. Lesion depth ranged from 175 to 606  μm in SS-OCT. A correlation between μCT and SS-OCT was found regarding lesion depth (R=0.81, p<0.001) and also surface layer thickness (R=0.76, p<0.005). The images obtained clinically in real time using the dental SS-OCT system are suitable for the assessment of natural subsurface lesions and their surface layer, providing comparable images to a laboratory high-resolution μCT without the use of x-ray. PMID:26158079

  11. Assessment of natural enamel lesions with optical coherence tomography in comparison with microfocus x-ray computed tomography.

    PubMed

    Espigares, Jorge; Sadr, Alireza; Hamba, Hidenori; Shimada, Yasushi; Otsuki, Masayuki; Tagami, Junji; Sumi, Yasunori

    2015-01-01

    A technology to characterize early enamel lesions is needed in dentistry. Optical coherence tomography (OCT) is a noninvasive method that provides high-resolution cross-sectional images. The aim of this study is to compare OCT with microfocus x-ray computed tomography ([Formula: see text]) for assessment of natural enamel lesions in vitro. Ten human teeth with visible white spot-like changes on the enamel smooth surface and no cavitation (ICDAS code 2) were subjected to imaging by μCT (SMX-100CT, Shimadzu) and 1300-nm swept-source OCT (Dental SS-OCT, Panasonic Health Care). In [Formula: see text], the lesions appeared as radiolucent dark areas, while in SS-OCT, they appeared as areas of increased signal intensity beneath the surface. An SS-OCT attenuation coefficient based on Beer-Lambert law could discriminate lesions from sound enamel. Lesion depth ranged from 175 to [Formula: see text] in SS-OCT. A correlation between [Formula: see text] and SS-OCT was found regarding lesion depth ([Formula: see text], [Formula: see text]) and also surface layer thickness ([Formula: see text], [Formula: see text]). The images obtained clinically in real time using the dental SS-OCT system are suitable for the assessment of natural subsurface lesions and their surface layer, providing comparable images to a laboratory high-resolution [Formula: see text] without the use of x-ray.

  12. Near-IR and PS-OCT imaging of developmental defects in dental enamel

    NASA Astrophysics Data System (ADS)

    Hirasuna, Krista; Fried, Daniel; Darling, Cynthia L.

    2007-02-01

    Polarization sensitive optical coherence tomography (PS-OCT) and near-IR (NIR) imaging are promising new technologies under development for monitoring early carious lesions. Fluorosis is a growing problem in the U.S., and the more prevalent mild fluorosis can be visually mistaken for early enamel demineralization. Some initial NIR images suggest that enamel defects and dental caries manifest different optical behavior in the NIR. Unfortunately, there is little quantitative information available regarding the differences in optical properties of sound enamel, enamel developmental defects, and demineralized enamel due to caries. This study tested the hypothesis that hypomineralized enamel due to fluorosis can be differentiated from demineralized enamel due to caries using NIR and PS-OCT imaging because of different optical behavior in the NIR. Thirty extracted human teeth with various degrees of suspected fluorosis and/or caries were imaged using PS-OCT and NIR transillumination. An InGaAs camera and a near-IR diode laser were used to measure the optical attenuation through transverse tooth sections (~200 μm). Developmental defects were clearly visible in the polarization-resolved OCT images, demonstrating that PS-OCT can be used to nondestructively measure the depth and possible severity of the defects. Enamel defects on whole teeth that could be imaged with high contrast with visible light were transparent in the near-IR while demineralized areas due to caries were opaque. In contrast, dental caries could be clearly distinguished from sound enamel. This study suggests that PS-OCT and NIR methods may potentially be used as tools to assess the severity and extent of enamel defects and for the differentiation of mild fluorosis defects from early carious lesions.

  13. In vitro inhibition of bovine enamel demineralization by enamel matrix derivative.

    PubMed

    Ran, Jin Mei; Ieong, Cheng Cheng; Xiang, Chen Yang; Lv, Xue Ping; Xue, Jing; Zhou, Xue Dong; Li, Wei; Zhang, Ling Lin

    2014-01-01

    This study aimed to determine whether enamel matrix derivative (Emdogain) affects the demineralization of bovine enamel in vitro and to assess the agent's anti-caries potential. Bovine enamel blocks were prepared and randomly divided into three groups (n = 15 per group), which were treated with distilled water (negative control), NaF (positive control), or Emdogain. All three groups were pH-cycled 12 times over 6 days. The percentage of surface enamel microhardness reduction (%SMHR), calcium demineralization rate (CDR), surface roughness, lesion depth and mineral loss after demineralization were examined. Surface morphology of specimens was studied by scanning electron microscopy. The Emdogain and positive control groups showed similar surface roughness, lesion depths and mineral loss, which were significantly lower than those in the negative control group. In addition, the enamel surfaces of both the Emdogain and NaF groups showed much narrower intercrystalline spaces than the surfaces of the negative control group, which exhibited extensive microfractures along the crystal edges. %SMHR differed significantly among all three groups, with the smallest value in the Emdogain group and the greatest in the negative control group. These results indicate that enamel matrix derivative (Emdogain) can significantly inhibit demineralization of bovine enamel in vitro, suggesting that it has potential as an anti-caries agent.

  14. Casein phosphopeptide-amorphous calcium phosphate incorporated into sugar confections inhibits the progression of enamel subsurface lesions in situ.

    PubMed

    Walker, G D; Cai, F; Shen, P; Adams, G G; Reynolds, C; Reynolds, E C

    2010-01-01

    Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) has been demonstrated to exhibit anticariogenic activity in randomized, controlled clinical trials of sugar-free gum and a tooth cream. Two randomized, double-blind, crossover studies were conducted to investigate the potential of CPP-ACP added to hard candy confections to slow the progression of enamel subsurface lesions in an in situ model. The confections studied were: (1) control sugar (65% sucrose + 33% glucose syrup); (2) control sugar-free; (3) sugar + 0.5% (w/w) CPP-ACP; (4) sugar + 1.0% (w/w) CPP-ACP; (5) sugar-free + 0.5% (w/w) CPP-ACP. Participants (10 and 14 in study 1 and 2) wore a removable palatal appliance containing enamel half-slabs with subsurface lesions, except for meals and oral hygiene procedures, and consumed 1 confection 6 times a day for 10 days. The enamel half-slabs were inset to allow the development of plaque on the enamel surface. Participants rested for 1 week before crossing over to another confection. The appliances were stored in a humid container at 37 degrees C when not in the mouth. After each treatment period, the enamel half-slabs were removed, paired with their demineralized control half-slabs, embedded, sectioned and then analysed using transverse microradiography. In both studies consumption of the control sugar confection resulted in significant demineralization (progression) of the enamel subsurface lesions. However, consumption of the sugar confections containing CPP-ACP did not result in lesion progression, but in fact in significant remineralization (regression) of the lesions. Remineralization by consumption of the sugar + 1.0% CPP-ACP confection was significantly greater than that obtained with the sugar-free confection.

  15. Evaluation of Diagnostic Tests Using Information Theory for Multi-Class Diagnostic Problems and its Application for the Detection of Occlusal Caries Lesions

    PubMed Central

    Arslan, Umut; Karaağaoğlu, Ergun; Özkan, Gökhan; Kanlı, Aydan

    2014-01-01

    Background: Several methods are available to evaluate the performance of the tests when the purpose of the diagnostic test is to discriminate between two possible disease states. However multi-class diagnostic problems frequently appear in many areas of medical science. Hence, there is a need for methods which will enable us to characterize the accuracy of diagnostic tests when there are more than two possible disease states. Aims: To show that two information theory measures, information content (IC) and proportional reduction in diagnostic uncertainty (PRDU), can be used for the evaluation of the performance of diagnostic tests for multi-class diagnostic problems that may appear in different areas of medical science. Study Design: Diagnostic accuracy study. Methods: Sixty freshly extracted permanent human molar and pre-molar teeth suspected to have occlusal caries lesions were selected for the study and were assessed by two experienced examiners. Each examiner performed two evaluations. Histological examination was used as the gold standard. The scores of the histological examination were defined as sound (n=11), enamel caries (n=22) and dentin caries (n=27). Diagnostic performance of i) visual inspection, ii) radiography, iii) laser fluorescence (LF) and iv) micro-computed tomography (M-CT) caries detection methods was evaluated by calculating IC and PRDU. Results: Micro-computed tomography examination was the best method among the diagnostic techniques for the diagnosis of occlusal caries in terms of both IC and PRDU. M-CT examination supplied the maximum diagnostic information about the diagnosis of occlusal caries in the first (IC: 1.056; p<0.05), (PRDU: 70.5%) and second evaluation (IC: 1.105; p<0.05), (PRDU: 73.8%) for the first examiner. M-CT examination was the best method among the diagnostic techniques for the second examiner in both the first (IC:1.105; p<0.05), (PRDU:73.8%) and second evaluation (IC:1.061; p<0.05), (PRDU:70.8%). IC and PRDU were

  16. Comparison Between Biofilm Production, Phospholipase and Haemolytic Activity of Different Species of Candida Isolated from Dental Caries Lesions in Children

    PubMed Central

    Shenoy, Neetha

    2016-01-01

    Introduction C.albicans is the most commonly isolated fungal pathogen in the oral cavity, but isolation of non-albicans Candida is increasing in recent years. We wish to demonstrate the virulence factors of Candida spp. isolated from the dental caries lesion of the children as presence of virulence factors determines the pathogenic potential of any microorganism. Aim To compare biofilm production, phospholipase and haemolytic activity of C.albicans with that of non-albicans species of Candida isolated from dental caries lesions of children to evaluate the role of non- albicans species of Candida in formation of dental caries. Materials and Methods Oral swabs were collected from caries lesion of 100 school children of age 5-10 years with dental caries. Candida isolates were tested for biofilm production, phospholipase and haemolytic activity. Statistical analysis was done by Chi-Square test and Mann-Whitney U test wherever applicable using SPSS version 11.5. Results Out of the 100 children with dental caries 37 were positive for Candida by smear or culture and 31 by culture. C.albicans was the most prevalent isolate followed by C.krusei, C.tropicalis and C.albicans. Out of 21 C.albicans isolates, 10 (47.6%) showed phospholipase activity and 18 (85.71%) produced biofilm. Of the 10 non-albicans strains, 5 (50%) showed phospholipase activity and 6 (60%) produced biofilm. All isolates of Candida produced haemolysin (100%). Conclusion There was no statistically relevant difference between the virulence factor production by C.albicans and non-albicans species of Candida. In other words, our study shows that both C.albicans and non-albicans species of Candida isolated from caries lesions of the children, produce these virulence factors. So we can say that non-albicans species of Candida also are involved in caries formation. PMID:27190803

  17. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis

    PubMed Central

    Rôças, Isabela N.; Rachid, Caio T. C. C.; Lima, Kenio C.; Assunção, Isauremi V.; Gomes, Patrícia N.; Siqueira, José F.

    2016-01-01

    This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection. PMID:27135405

  18. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

    PubMed

    Rôças, Isabela N; Alves, Flávio R F; Rachid, Caio T C C; Lima, Kenio C; Assunção, Isauremi V; Gomes, Patrícia N; Siqueira, José F

    2016-01-01

    This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

  19. In Situ analysis of CO2 laser irradiation on controlling progression of erosive lesions on dental enamel.

    PubMed

    Lepri, Taísa Penazzo; Scatolin, Renata Siqueira; Colucci, Vivian; De Alexandria, Adílis Kalina; Maia, Lucianne Cople; Turssi, Cecília Pedroso; Corona, Silmara Aparecida Milori

    2014-08-01

    The present study aimed to evaluate in situ the effect of CO2 laser irradiation to control the progression of enamel erosive lesions. Fifty-six slabs of bovine incisors enamel (5 × 3 × 2.5 mm(3) ) were divided in four distinct areas: (1) sound (reference area), (2) initial erosion, (3) treatment (irradiated or nonirradiated with CO2 laser), (4) final erosion (after in situ phase). The initial erosive challenge was performed with 1% citric acid (pH = 2.3), for 5 min, 2×/day, for 2 days. The slabs were divided in two groups according to surface treatment: irradiated with CO2 laser (λ = 10.6 µm; 0.5 W) and nonirradiate. After a 2-day lead-in period, 14 volunteers wore an intraoral palatal appliance containing two slabs (irradiated and nonirradiated), in two intraoral phases of 5 days each. Following a cross-over design during the first intraoral phase, half of the volunteers immersed the appliance in 100 mL of citric acid for 5 min, 3×/day, while other half of the volunteers used deionized water (control). The volunteers were crossed over in the second phase. Enamel wear was determined by an optical 3D profilometer. Three-way ANOVA for repeated measures revealed that there was no significant interaction between erosive challenge and CO2 laser irradiation (P = 0.419). Erosive challenge significantly increased enamel wear (P = 0.001), regardless whether or not CO2 laser irradiation was performed. There was no difference in enamel wear between specimens CO2 -laser irradiated and non-irradiated (P = 0.513). Under intraoral conditions, CO2 laser irradiation did not control the progression of erosive lesions in enamel caused by citric acid.

  20. Structure of artificial enamel lesions after topical applications of high-concentration sodium fluoride solution in vitro.

    PubMed

    Wen, H B; Cui, F Z; Chen, X Q; Wang, Q; Li, H D

    1995-01-01

    A three-layer structure, including a columnar layer (CL), a buffer layer, and unaffected intact enamel, was successively formed from the outer to the inner part of artificial enamel lesions (AEL) by topical applications of a high-concentration acidic sodium fluoride solution (10,000 ppm, pH 5.6) in vitro. The AEL was produced in bovine enamel that was decalcified for 5 days in a lactic acid gel system. The morphological observations by using scanning electron microscopy showed that the CL was made of columnar deposits of small globules about 0.5 microns in diameter. It was observed for the first time that small globules filled the demineralized interprismatic regions in the buffer layer. The unaffected intact enamel was protected from further demineralization under the acidic condition. Structure and composition of the CL were investigated by using X-ray diffraction and X-ray photoelectron spectroscopy. In the CL the atomic ratio was Ca:P = 12.6 and Ca:F = 0.75, and the small globules were mainly a mixture of polycrystalline calcium fluoride and hydroxyapatite. For comparison, the sound enamel and the AEL attained by applications of 0 and 100 ppm acidic sodium fluoride solutions (pH 5.6) were also investigated. The formation mechanism of the three-layer structure and the related cariostatic effects are discussed.

  1. Detecting and treating occlusal caries lesions: a cost-effectiveness analysis.

    PubMed

    Schwendicke, F; Stolpe, M; Meyer-Lueckel, H; Paris, S

    2015-02-01

    The health gains and costs resulting from using different caries detection strategies might not only depend on the accuracy of the used method but also the treatment emanating from its use in different populations. We compared combinations of visual-tactile, radiographic, or laser-fluorescence-based detection methods with 1 of 3 treatments (non-, micro-, and invasive treatment) initiated at different cutoffs (treating all or only dentinal lesions) in populations with low or high caries prevalence. A Markov model was constructed to follow an occlusal surface in a permanent molar in an initially 12-y-old male German patient over his lifetime. Prevalence data and transition probabilities were extracted from the literature, while validity parameters of different methods were synthesized or obtained from systematic reviews. Microsimulations were performed to analyze the model, assuming a German health care setting and a mixed public-private payer perspective. Radiographic and fluorescence-based methods led to more overtreatments, especially in populations with low prevalence. For the latter, combining visual-tactile or radiographic detection with microinvasive treatment retained teeth longest (mean 66 y) at lowest costs (329 and 332 Euro, respectively), while combining radiographic or fluorescence-based detections with invasive treatment was the least cost-effective (<60 y, >700 Euro). In populations with high prevalence, combining radiographic detection with microinvasive treatment was most cost-effective (63 y, 528 Euro), while sensitive detection methods combined with invasive treatments were again the least cost-effective (<59 y, >690 Euro). The suitability of detection methods differed significantly between populations, and the cost-effectiveness was greatly influenced by the treatment initiated after lesion detection. The accuracy of a detection method relative to a "gold standard" did not automatically convey into better health or reduced costs. Detection methods

  2. Measurement of surface hardness of primary carious lesions in extracted human enamel -measurement of Knoop hardness using Cariotester.

    PubMed

    Shimizu, Akihiko; Yamamoto, Takatsugu; Nakashima, Syozi; Nikaido, Toru; Sugawara, Toyotaro; Momoi, Yasuko

    2015-01-01

    The clinical feasibility of a novel device called a Cariotester was investigated by measuring the Knoop hardness (KHN) of white spot lesions diagnosed as ICDAS code 1, 2 or 3. To obtain an equation for converting the Cariotester indentation depth into the KHN, a regression analysis was performed between the depth and measured KHN for human enamel. The Cariotester was then used to measure the indentation depth for white spots (ICDAS code 1, 2 or 3) in extracted teeth, and the KHN values were determined using the above equation. The KHN was 219.9±19.7, 162.4±24.0 and 31.7±17.5 for code 1, 2 and 3 lesions, respectively, which was 30, 49 and 90% lower than that for healthy enamel. Using the formula reported in the literature, the mineral density was calculated to be 87.7 vol.% for healthy enamel, and 75.1, 66.1 and 35.5 vol.% for code 1, 2 and 3 lesions, respectively.

  3. Serial removal of caries lesions from tooth occlusal surfaces using near-IR image-guided IR laser ablation

    NASA Astrophysics Data System (ADS)

    Chan, Kenneth H.; Tom, Henry; Darling, Cynthia L.; Fried, Daniel

    2015-02-01

    Previous studies have established that caries lesions can be imaged with high contrast without the interference of stains at near-IR wavelengths greater than 1300-nm. It has been demonstrated that computer controlled laser scanning systems utilizing IR lasers operating at high pulse repetition rates can be used for serial imaging and selective removal of caries lesions. In this study, we report our progress towards the development of algorithms for generating rasterized ablation maps from near-IR reflectance images for the removal of natural lesions from tooth occlusal surfaces. An InGaAs camera and a filtered tungsten-halogen lamp producing near-IR light in the range of 1500-1700-nm were used to collect crosspolarization reflectance images of tooth occlusal surfaces. A CO2 laser operating at a wavelength of 9.3- μm with a pulse duration of 10-15-μs was used for image-guided ablation.

  4. The wolf in sheep’s clothing: Microtomographic aspects of clinically incipient radiation-related caries

    PubMed Central

    Morais-Faria, Karina; Neves-Silva, Rodrigo; Lopes, Marcio-Ajudarte; Ribeiro, Ana-Carolina-Prado; de Castro Jr, Gilberto; da Conceição-Vasconcelos, Karina-Gondim-Moutinho; Brandão, Thais-Bianca; Santos-Silva, Alan-Roger

    2016-01-01

    Background Radiation-related caries (RRC) can cause rapid progression, with a high potential for dental destruction affecting mainly cervical and incisal areas. Unlike the injuries that occur in the conventional caries, incipient RRC present in unusual surfaces have difficult diagnosis and classification stages of cavitation. Material and Methods Evaluate the radiographic patterns of demineralization of RRC by using micro-CT. Ten teeth with incipient RRC and 10 teeth with incipient conventional caries (control group) matched by anatomic teeth group and caries affected surfaces were evaluated by X-ray microtomography (micro-CT) Skyscan 1174V2 (50Kv, 1.3 megapixel, Kontich, Belgium). Teeth were placed in a standard position for micro-CT (coronal, transaxial and sagittal sections) during images acquisition. Lesions were classified according to the depth of invasion and relationship with enamel, dentin and pulp. Results RRC samples presented deeper lesions with higher involvement of enamel and dentin. Control group presented focal and superficial lesions with lower involvement of enamel and dentin. Conclusions Incipient RRC present aggressive microtomographic patterns of demineralization when compared to conventional caries, as indicated by deep lesions, regardless of its clinically incipient aspects. Key words:Head and neck cancer, radiotherapy, microtomography, radiation caries. PMID:26946198

  5. Reversal of primary root caries using a dentifrice with a high fluoride content.

    PubMed

    Lynch, E; Baysan, A

    2001-01-01

    Root caries is a widespread problem and can be quite serious in older populations. The restoration of root carious lesions is often difficult. Compared to enamel caries, there has been limited research into the pharmaceutical management of primary root caries lesions (PRCLs), and many of these studies have been carried out in vitro, with limited numbers of clinical trials. Fluoride is presently a cornerstone in dentifrice formulations for cost-effective and anticaries therapy. It is generally accepted that fluoride ions promote remineralization of tooth substances and reduce the rate of demineralization. The use of a dentifrice with a high fluoride content may be considered to reverse PRCLs, since more fluoride is required for the remineralization of roots than for enamel. This paper reviews the effects of dentifrices with high fluoride contents on the management of root caries.

  6. The influence of the caries definition on disease prevalence and distribution in 20-23 year old persons in Stockholm.

    PubMed

    Wikner, S

    1993-01-01

    The aim was to investigate to what extent an extension of the caries criterion into the dentin, may influence the need for therapeutical intervention. Using a computerized technic, the depth of all approximal lesions in posterior teeth in 151 persons, aged 20 and 23 years, were measured on magnified (x5) radiographs and expressed as per cent of the enamel width. The proportion diseased 20 year old persons was 88% if the criterion was any sign of caries but only 50% if the criterion was at least one lesion, reaching the dentin. When caries was defined as a lesion having a depth, corresponding the double enamel width the figure was 11% and the proportion surfaces in need of therapeutical treatment constituted 2% of the total caries volume. It is concluded that an extension of the filling criterion into the superficial layers of the dentin may reduce the need for filling therapy in 20 year old persons to a very low level.

  7. A comparative evaluation of remineralizing ability of bioactive glass and amorphous calcium phosphate casein phosphopeptide on early enamel lesion

    PubMed Central

    Palaniswamy, Udaya Kumar; Prashar, Neha; Kaushik, Mamta; Lakkam, Surender Ram; Arya, Shikha; Pebbeti, Swetha

    2016-01-01

    Background: This study was done to evaluate remineralizing potential of bioactive glasses (BAGs) and amorphous calcium phosphate-casein phosphopeptide (ACP-CPP) on early enamel lesion. Materials and Methods: Twenty freshly extracted mandibular premolars were sectioned sagittally. The buccal half was impregnated in acrylic resin blocks and treated with 37% phosphoric acid in liquid form, to demineralize enamel surface to simulate early enamel lesion. The samples were divided into two groups. The samples in Group I were treated with ACP-CPP (GC Tooth Mousse) and in Group II with BAG (Sensodyne Repair and Protect) and stored in saliva to prevent dehydration. The samples were tested for microhardness. The data obtained was analyzed using ANOVA post hoc multiple comparison and independent sample t- test and presented as a mean and standard deviation. Results: All the samples showed a decrease in the microhardness after demineralization. After application of remineralizing agents, Group II showed a highly significant increase in the microhardness (P < 0.05) after 10 days, while Group I showed a significant increase in microhardness after 15 days (P < 0.05). Conclusion: Both the remineralizing agents tested in this study can be considered effective in repair and prevention of demineralization. BAG showed better results initially, but eventually both have similar remineralizing potential. PMID:27605985

  8. Brief communication: a pilot study: smooth surface early caries (caries incipiens) detection with KaVo DIAGNODent in historical material.

    PubMed

    Tomczyk, Jacek; Komarnitki, Iulian; Olczak-Kowalczyk, Dorota

    2013-03-01

    In many odontological studies concerning archeological material, there is no analysis of early caries lesions (caries incipiens) that manifest as a carious spot. At this stage of caries, the enamel is still hard, and thus, it is impossible to diagnose caries by visual methods. We assessed the usefulness of the DIAGNODent pen (DD laser) in analyzing noncavity lesions on the smooth surface sites of crowns from historical populations. Twenty-seven individuals were examined: 18 from Radom (Poland), and nine from Tell Masaikh and Terqa (Syria). A total of 562 teeth were characterized. The series represented different climatic zones, but were dated from the similar period, 18th to 19th century AD. We used four diagnostic techniques: visual, DD laser, radiographic, and histological as the gold standard. DD laser showed that the mean values of healthy enamel in both series did not exceed 15 units. The mean values of smooth and rough spots in the Syrian population were significantly higher than those from Poland. This study showed that all the noncarious spots from the Radom series did not exceed 30 units. In the Syrian samples, this limit was higher at 44 units. These results were confirmed by histology and radiography. The DD laser provided good results in detecting dentine carious lesions in historical material, but its efficiency in diagnosing early caries (caries incipiens) remains uncertain based on the presented series.

  9. Enamel loss associated with orthodontic adhesive removal on teeth with white spot lesions: an in vitro study.

    PubMed

    Tüfekçi, Eser; Merrill, Thomas E; Pintado, Maria R; Beyer, John P; Brantley, William A

    2004-06-01

    Teeth with white spot lesions (WSL) might be more prone to enamel loss during bracket debonding. This in vitro study compared enamel loss from teeth with (n = 14) and without (n = 14) WSL after polishing with low-speed finishing burs or disks (Sof-Lex, 3M ESPE, St Paul, Minn). Debonded surfaces were analyzed with a contact stylus profilometer, and digitized data were compared with baseline readings by using AnSur NT software (Regents, University of Minnesota, Minneapolis, Minn). Specimen surfaces were also examined with a scanning electron microscope. Two-way analysis of variance was performed to analyze the data. In teeth without WSL, the volume losses were 0.16 mm(3) for the bur group and 0.10 mm(3) for the disk group; the mean maximum depths were 47.7 microm for the bur group and 54.3 microm for the disk group. In teeth with WSL, the volume losses were 0.06 and 0.17 mm(3), and the mean maximum depths were 35.1 and 48.7 microm for the bur and disk groups, respectively. There were no significant differences in enamel loss between the 2 groups of teeth without WSL (P =.12). However, in teeth with WSL, the burs removed less enamel than the disks (P = 0.006). Scanning electron microscope examination showed that any damage on the enamel surface was usually located in the cervical third of the teeth. On most specimens, even though tooth surfaces appeared resin-free to the naked eye, there were remnants of it. The differences between groups were so small that they might be clinically insignificant.

  10. Eroded enamel lesion remineralization by saliva as a possible factor in the site-specificity of human dental erosion.

    PubMed

    Amaechi, B T; Higham, S M

    2001-08-01

    The composition and flow of saliva, which determine its functions, vary within intraoral sites and among individuals. Also, the susceptibility to tooth erosion reportedly varies among individuals and within the dental arches. A possible effect of saliva on early-eroded lesions may be a contributory factor. The aims here were firstly to determine the remineralization of eroded enamel lesions by saliva, and secondly to investigate any variation of this remineralization within the dental arches and among individuals. Early enamel erosion was produced on human premolars using orange juice. Control sections and two test slabs were cut from each tooth. The two slabs from the same lesion were bonded with composite resins to the palatal surface of upper right lateral incisor teeth and the lingual surface of the lower right lateral incisor teeth of volunteers, who then chewed a sugar-free gum four times daily. After 28-day intraoral exposure, mineral loss (DeltaZ) and lesion depth (ld) were quantified using microradiography and the data analysed by paired t-test (n=10, alpha=0.05). Mean DeltaZ was significantly lower in the group of slabs positioned palatally (P<0.001) and lingually (P<0.001) when compared with the control group, and in the lingually placed group when compared with the palatally positioned (P<0.01). A significantly lower ld was observed in the group of slabs positioned palatally (P<0.05) and lingually (P<0.001) when compared with the control group, and in the lingually positioned group when compared with the palatally placed (P<0.05). It was concluded that saliva can remineralize early enamel erosion, and that the degree of remineralization varies within intraoral sites and may be responsible for the differing susceptibility to erosion within the dental arches.

  11. An in vitro evaluation of selective demineralised enamel removal using bio-active glass air abrasion.

    PubMed

    Banerjee, Avijit; Pabari, Hiten; Paolinelis, George; Thompson, Ian D; Watson, Timothy F

    2011-12-01

    Unnecessary over-preparation of carious enamel often occurs clinically during operative caries management. The working hypothesis to be investigated in this study is the potential for bio-active glass air abrasion to remove selectively only demineralised enamel in artificial enamel lesions when compared to equivalent alumina air abrasion, so potentially minimising cavity over-preparation. Bisected artificial, paired smooth surface enamel lesions on ethics-approved, extracted sound human molars were created and subsequently air abraded with 27 μm alumina (n = 19) and bio-active glass (n = 19). The difference between pre-operative lesion boundary and post-operative cavity margin was calculated following optical confocal fluorescent assessment of the lesion boundary. Data indicated mean% over-preparation (sound enamel removal) of 176% with alumina and 15.2% for bio-active glass (p = 0.005). Bio-active glass abrasion removed completely the demineralised enamel from artificial lesions with clinically insignificant over-preparation of sound tissue, indicating technique selectivity towards grossly demineralised enamel. Alumina air abrasion resulted in substantial enamel removal in both sound and demineralised tissues indicating the operator selectivity required to use the techniques effectively in clinical practice.

  12. Shedding New Light on Early Caries Detection

    PubMed Central

    Choo-Smith, Lin-P'ing; Dong, Cecilia C.S.; Cleghorn, Blaine; Hewko, Mark

    2009-01-01

    Dental caries continues to be a common chronic disease among various population groups. Patient care can be improved with detection at the earliest stage. However, current techniques do not have sufficient sensitivity and specificity. We discuss 2 new methods — optical coherence tomography (OCT) and polarized Raman spectroscopy (PRS) — that are potentially useful for early caries detection and monitoring. OCT produces morphologic depth images of near-surface tissue structures with a resolution that is an order of magnitude greater than ultrasound imaging. Based on measurement of back-scattered near infrared light, OCT shows that sound enamel causes high-intensity back-scattering at the tooth surface that decreases rapidly with depth. In contrast, incipient lesions cause higher light back-scattering at the tooth surface and subsurface scattering indicative of porosity caused by demineralization. The scatter region within the enamel correlates well with the classical triangular shape of subsurface lesions observed in histologic sections. OCT imaging not only allows identification of incipient lesions, but also provides information on surface integrity and lesion depth. PRS furnishes biochemical information about the tooth's composition, mineral content and crystallinity. The depolarization ratio derived from the dominant phosphate peak of hydroxyapatite in sound teeth is consistently lower than that from incipient caries. This difference is attributed to the change in enamel crystallite morphology or orientation that occurs with acid demineralization. Thus, PRS can be used to confirm suspect lesions determined by OCT and rule out false-positive signals from non-carious anomalies. The combination of OCT and PRS provides a new detection method with high sensitivity and specificity that will improve caries management and patient care. Future studies are aimed at developing intraoral probes to validate the findings in vivo. PMID:19126361

  13. Genetic Variation in MMP20 Contributes to Higher Caries Experience

    PubMed Central

    Tannure, Patricia Nivoloni; Kuchler, Erika Calvano; Lips, Andrea; de Castro Costa, Marcelo; Luiz, Ronir Raggio; Granjeiro, Jose Mauro; Vieira, Alexandre Rezende

    2012-01-01

    Summary Matrix metalloproteinases play an important role during the initial process of enamel development and therefore may play a role in caries. Objectives To evaluate the association between MMP20 and caries experience in Brazilian children. Methods Eligible unrelated children with or without caries were evaluated using a cohort design. Demographic data and oral health habits were obtained though a questionnaire. Caries data was collected by clinical examination. Genotyping of the selected polymorphism was carried out by real-time PCR from genomic DNA. Allele and genotype frequencies were compared between groups with distinct caries experience and oral health habits. Results Of 388 subjects, 161 were caries free children. There were no differences between caries levels and genotype distribution in the total cohort. When ethnic background was considered, differences in genotype distribution were observed in caries free children versus children with caries in Caucasians (p=0.03). Differences could also be seen when poor oral hygiene was used to stratify the analysis (p=0.02). Regression analysis, adjusted for genotype and ethnicity, confirmed that ingestion of sweets between meals increases the risk of presenting carious lesions (p=0.00001; OR=2.33; 95%CI 1.53–3.54). Conclusion Variation in MMP20 may be associated with caries experience mainly in Caucasian subjects with poor oral health habits. PMID:22330321

  14. The caries balance: the basis for caries management by risk assessment.

    PubMed

    Featherstone, John D B

    2004-01-01

    Dental caries progression or reversal depends upon the balance between demineralization and remineralization. The 'Caries Balance' is determined by the relative weight of the sums of pathological factors and protective factors. Minimally invasive dentistry aims at the least possible removal of enamel or dentin, including reducing pathological factors and enhancing remineralization to avoid any removal of hard tissues. A structured caries risk assessment should be carried out based upon the concept of the caries balance. Following the risk assessment a treatment plan is devised which leads to the control of dental caries for the patient. The balance between pathological and preventive factors can be swung in the direction of caries intervention and prevention by the active role of the dentist and his/her auxiliary staff. Much is now understood about the mechanism of dental caries. We have known for a long time that demineralization of enamel, dentin or cementum is caused by organic acids that are generated by so-called acidogenic bacteria in the plaque when these bacteria feed upon fermentable carbohydrates (Silverstone, 1973; Featherstone, 2000; Loesche, 1986). The natural repair process is remineralization, which occurs when the pH rises again and calcium and phosphate from saliva together with fluoride enter the subsurface region of the lesion and form a new veneer on the existing crystal remnants in the lesion (Ten Cate and Featherstone, 1991). This veneer is less soluble than the original mineral and resists further acid attacks. The key to improved dental health for all is now for the dental profession to embrace this knowledge and put it into practice in the real world, to inhibit caries formation and progression, and to enhance the natural repair process.

  15. A Comparative Analysis of Caries Inhibitory Effect of Remineralizing Agents on Human Enamel Treated With Er:YAG Laser: An In-vitro Atomic Emission Spectrometry Analysis

    PubMed Central

    Nair, Aswin Saseendran; Kumar, R Krishna; Ahameed, Syed Shaheed; Punnathara, Sairaj; Peter, Joby

    2016-01-01

    Introduction The tug of war to maintain tooth integrity is dependent on a ratio between demineralization and remineralization. Hence, demineralization should be retarded and remineralization should be enhanced to maintain a natural equilibrium in the oral cavity. Aim To compare in-vitro acid resistance of human enamel when using Casein Phosphopeptides Amorphous Calcium Phosphate (CPP-ACP) [GC Tooth mousse] cream, Casein Phosphopeptide Amorphous Calcium Fluoride Phosphate (CPP-ACFP) [GC Tooth mousse plus] cream, Er:YAG laser alone, combination of CPP-ACP with Er:YAG laser, CPP-ACFP with Er:YAG laser. Materials and Methods An in-vitro study was done on 100 specimens which were prepared from 50 human premolars to investigate the caries inhibitory effect of remineralizing agents and laser on enamel using an atomic emission spectrometry analysis. The enamel specimens were randomly allocated into 6 groups: Untreated (control); CPP-ACP (GC Tooth mousse); CPP-ACFP (GC Tooth mousse plus); Er:YAG laser treatment alone; CPP-ACP with Er:YAG laser; CPP-ACFP with Er: YAG laser. Then specimens were immersed individually in 5ml of acetate buffer solution (0.1mol/L, pH 4.5) and incubated at 37°C for 24 hours, to determine the acid resistance by analyzing the calcium release using atomic emission spectrometry. An ANOVA model was constructed (p-value 0.05), followed by post-hoc Tukey’s test for multiple pair wise comparisons of mean values. Results There was a significant difference among the various groups with respect to amount of calcium released (p<0.001). The lowest mean score of calcium release was observed for CPP-ACFP with Er:YAG laser followed by CPP-ACFP but the differences between these groups were statistically not significant (p>0.05). Similarly the differences between CPP-ACP with Er:YAG laser and CPP-ACP also were not significant (p>0.05). The highest mean score of calcium release was for Er:YAG laser and no significant statistical difference was noticed in

  16. Stress and strain distribution in demineralized enamel: A micro-CT based finite element study.

    PubMed

    Neves, Aline Almeida; Coutinho, Eduardo; Alves, Haimon Diniz Lopes; de Assis, Joaquim Teixeira

    2015-10-01

    Physiological oral mechanical forces may play a role on the progression of enamel carious lesions to cavitation. Thus, the aim of this study was to describe, by 3D finite element analysis, stress, and strain patterns in sound and carious enamel after a simulated occlusal load. Micro-CT based models were created and meshed with tetrahedral elements (based on an extracted third molar), namely: a sound (ST) and a carious tooth (CT). For the CT, enamel material properties were assigned according to the micro-CT gray values. Below the threshold corresponding to the enamel lesion (2.5 g/cm(3) ) lower and isotropic elastic modulus was assigned (E = 18 GPa against E1  = 80 GPa, E2  = E3  = 20 GPa for sound enamel). Both models were imported into a FE solver where boundary conditions were assigned and a pressure load (500 MPa) was applied at the occlusal surface. A linear static analysis was performed, considering anisotropy in sound enamel. ST showed a more efficient transfer of maximum principal stress from enamel to the dentin layer, while for the CT, enamel layer was subjected to higher and concentrated loads. Maximum principal strain distributions were seen at the carious enamel surface, especially at the central fossa, correlating to the enamel cavity seen at the original micro-CT model. It is possible to conclude that demineralized enamel compromises appropriate stress transfer from enamel to dentin, contributing to the odds of fracture and cavitation. Enamel fracture over a dentin lesion may happen as one of the normal pathways to caries progression and may act as a confounding factor during clinical diagnostic decisions.

  17. Management of patients with active caries.

    PubMed

    Milgrom, Peter

    2014-07-01

    This paper reports on a mechanism to manage caries as a disease and to medically intervene in the disease process to halt progression. The goal of this paper is to provide this alternative to a surgical-only approach. The management of caries begins with assessing lesion activity and the potential for arrest. This requires a clinical and radiological assessment and evaluation of risk. Hopeless teeth are extracted and large cavities filled to reduce infection. Risk reduction strategies are employed so efforts to arrest lesions can be successful. Teeth with lesions in the enamel or outer third of the dentin should be sealed, not restored, as restorations can weaken teeth and can be traumatic to pulps.

  18. In vitro Induction of residual caries lesions in dentin: comparative mineral loss and nano-hardness analysis.

    PubMed

    Schwendicke, Falk; Eggers, Kerrin; Meyer-Lueckel, Hendrik; Dörfer, Christof; Kovalev, Alexander; Gorb, Stanislav; Paris, Sebastian

    2015-01-01

    Artificially inducing dentinal lesions mimicking those remaining after selective excavation should allow to investigate the effects and limits of such selective excavation, for example regarding the mechanical properties of treated teeth or the remineralisation of sealed residual lesions. Such analyses might otherwise be limited by the variability of natural lesions or ethical and practical concerns. This study compared different demineralisation protocols for their suitability to induce lesions similar to natural residual caries. Twelve natural deep lesions were excavated until leathery dentin remained, and analysed for their mineral loss (ΔZ), lesion depth (LD), mineral loss ratio (R), the slope of the mineral gradient and their nano-hardness profile. Artificial lesions were induced using four different demineralisation protocols (acetic acid pH = 4.95; 0.1 M lactic acid gel pH = 5.0; 0.5 M ethylenediaminetetraacetic acid pH = 7.2; Streptococcus mutans biofilms) and their depths monitored over different demineralisation times. Lesions with depths most according to those of natural lesions were analysed using transversal microradiography. Lesions induced by acetic acid solution did not significantly differ with regards to LD, ΔZ, R and mineral profile. Seven dentin specimens were subsequently submitted to a moderately acidic (pH = 5.3) methylhydroxydiphosphonate-buffered acetate solution for 12 weeks. Natural and artificial residual lesions were similarly deep (mean ± SD: LD = 626 ± 212 and 563 ± 88 µm), demineralised (R = 19.5 ± 4.7 and 29.8 ± 4.1%), showed a flat and continuous mineral gradient (slope = 0.10 ± 0.05 and 0.13 ± 0.06 vol%/µm) and did not significantly differ regarding their nano-hardness profile. The described protocol induces lesions with mineral content and mechanical properties similar to natural residual lesions.

  19. How do dental students determine patients' caries risk level using the Caries Management By Risk Assessment (CAMBRA) system?

    PubMed

    Doméjean, Sophie; Léger, Stéphanie; Rechmann, Peter; White, Joel M; Featherstone, John D B

    2015-03-01

    Research has demonstrated the validation of specific caries risk assessment (CRA) systems, but little is known about how dental practitioners assign a caries risk level to their patients. The aim of this study was to explore dental students' decision making in caries risk assignment when using the Caries Management By Risk Assessment (CAMBRA) system. Multiple correspondence analysis and chi-squared automated interaction detector analysis were performed on data collected retrospectively for a period of six years (2003-09) at the University of California, San Francisco predoctoral dental clinic. The study population consisted of 12,952 patients from six years of age through adult who received a baseline CRA during the period, were new to CAMBRA, and had not received any prior CAMBRA recommendations. The results showed variation in decision making and risk level assignment, illustrated by the range of percentages for the three scores (low, moderate, and high/extreme caries risk) when CRA was assigned for the first time. For those first-time CRAs, decision making was mainly based on four factors: cavities or caries lesions into dentin on radiograph, restorations during the last three years due to caries, visible heavy plaque, and interproximal lesions into enamel (by radiographs). This study's findings provide important data regarding one group of CAMBRA users and thus contribute to the development of knowledge about the implementation of caries risk assessment in contemporary dental practice.

  20. Air-rotor stripping and enamel demineralization in vitro.

    PubMed

    Twesme, D A; Firestone, A R; Heaven, T J; Feagin, F F; Jacobson, A

    1994-02-01

    This investigation sought to evaluate the effects of air-rotor stripping on the susceptibility of human enamel to demineralization using an in vitro caries model. Crowns of extracted premolar teeth were abraded (0.5 mm) on one proximal surface by air-rotor stripping. The teeth were placed in a demineralizing gel and removed at various intervals up to 336 hours. Lesion depth and mineral content on the abraded and intact surfaces was measured with contact microradiography and computerized image analysis (double window technique). For each time interval measured, lesion depth was greater (p < 0.05) on the abraded surfaces and mineral density was significantly less (p < 0.05). In a second experiment, the effect of fluoride supplements (dentifrice or topical gel) were examined on abraded and intact enamel surfaces that were exposed to the acid gel for 192 hours. The data showed that fluoride treatments significantly reduced lesion penetration on intact and abraded surfaces compared with a no fluoride group. Lesion depth on the abraded, fluoride treated surfaces was significantly greater (p < 0.05) than on the intact untreated surfaces. No significant differences (p < 0.05) were apparent between the fluoride treatment groups with respect to lesion depth and mineral density within the lesion. These results suggest that air-rotor stripping significantly increases the susceptibility of proximal enamel surfaces to demineralization. As a result, the clinician should use caution in the application of this technique until the long-term effects on caries susceptibility have been determined.

  1. Hyperspectral laser-induced autofluorescence imaging of dental caries

    NASA Astrophysics Data System (ADS)

    Bürmen, Miran; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2012-01-01

    Dental caries is a disease characterized by demineralization of enamel crystals leading to the penetration of bacteria into the dentine and pulp. Early detection of enamel demineralization resulting in increased enamel porosity, commonly known as white spots, is a difficult diagnostic task. Laser induced autofluorescence was shown to be a useful method for early detection of demineralization. The existing studies involved either a single point spectroscopic measurements or imaging at a single spectral band. In the case of spectroscopic measurements, very little or no spatial information is acquired and the measured autofluorescence signal strongly depends on the position and orientation of the probe. On the other hand, single-band spectral imaging can be substantially affected by local spectral artefacts. Such effects can significantly interfere with automated methods for detection of early caries lesions. In contrast, hyperspectral imaging effectively combines the spatial information of imaging methods with the spectral information of spectroscopic methods providing excellent basis for development of robust and reliable algorithms for automated classification and analysis of hard dental tissues. In this paper, we employ 405 nm laser excitation of natural caries lesions. The fluorescence signal is acquired by a state-of-the-art hyperspectral imaging system consisting of a high-resolution acousto-optic tunable filter (AOTF) and a highly sensitive Scientific CMOS camera in the spectral range from 550 nm to 800 nm. The results are compared to the contrast obtained by near-infrared hyperspectral imaging technique employed in the existing studies on early detection of dental caries.

  2. Comparative analysis of optical coherence tomography signal and microhardness for demineralization evaluation of human tooth enamel

    NASA Astrophysics Data System (ADS)

    de Cara, Ana Claudia Ballet; Zezell, Denise Maria; Ana, Patricia A.; Deana, Alessandro Melo; Amaral, Marcello Magri; Dias Vieira, Nilson, Jr.; de Freitas, Anderson Zanardi

    2012-06-01

    The diagnosis of dental caries at an early stage enables the implementation of conservative treatments based on dental preservation. Several diagnostic methods have been developed, like visual-tactile and radiographic are the most commons but are limited for this application. The Optical Coherence Tomography is a technique that provides information of optical properties of enamel, which may change due to the decay process. The objective of this study was to evaluate the ability of OCT to detect different stages of demineralization of tooth enamel during the development of artificial caries lesions, taking as a reference standard for comparison sectional microhardness testing. Different stages of caries lesions were simulated using the pH cycling model suggested Feathestone and modified by Argenta. The samples were exposed to 0 (control group), 5, 10, 15, 20 and 25 days at a daily regimen of three hours demineralization followed by remineralization during 20 hours. It was used an OCT system with at 930nm. Sectional images were generated in all lesion region. The results obtained from the OCT technique presented similar behavior to microhardness, except for the group 25 days, due to inability to perform indentations reading in areas of more intense demineralization. A linear relationship was observed between the OCT and microhardness techniques for detection of demineralization in enamel. This relationship will allow the use of OCT technique in quantitative assessment of mineral loss and for the evaluation of incipient caries lesions.

  3. Application of NIR Raman spectroscopy for detecting and characterizing early dental caries

    NASA Astrophysics Data System (ADS)

    Ko, A. C.; Choo-Smith, L.-P.; Zhu, R.; Hewko, M.; Dong, C.; Cleghorn, B.; Sowa, M. G.

    2006-02-01

    Early dental caries detection facilitates implementation of non-surgical methods for arresting caries progression and promoting tooth remineralization. We present a method based on Raman spectroscopy with near-IR laser excitation to provide biochemical contrast for detecting and characterizing incipient carious lesions found in extracted human teeth. Changes in Raman spectra are observed in PO 4 3- vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various intensities of the PO 4 3- ν2, ν3, ν4 vibrations showed consistent increased intensities in spectra of carious lesions compared to sound enamel. The spectral changes are attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. This hypothesis is supported by reduced Raman polarization anisotropy derived from polarized Raman spectra of carious lesions. Polarized Raman spectral imaging of carious lesions found on whole (i.e. un-sectioned) tooth samples will also be presented.

  4. Dental caries patterns in preschool children.

    PubMed

    Johnsen, D C

    1984-01-01

    Management of dental caries as a disease requires the same level of skill and broad perspective as managing many other diseases. Dental caries has several variations, four of which were presented here. Long-term outlook for children with two of the caries patterns (those secondary to fissure defects or hypoplastic defects) is good if the teeth are restored. Management of children with nursing caries often involves dealing with well-intentioned but overindulgent parents. Prevention of nursing caries goes beyond simply informing the parents of potential dangers from excessive feeding with the bottle. Hypoplastic defects can resemble nursing caries; the differentiation is important in treating the child. The child with extensive proximal molar lesions may be the most difficult to manage on a long-term basis. A successful prevention program will mean a change in life style for the parent and child. The child with a cleft lip and/or palate has the disadvantages of enamel defects and a significant medical condition inviting overindulgence.

  5. OCT of early dental caries: a comparative study with histology and Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Hewko, Mark D.; Choo-Smith, Lin-P'ing; Ko, Alex C.; Leonardi, Lorenzo; Dong, Cecilia C.; Cleghorn, Blaine; Sowa, Michael G.

    2005-03-01

    Early dental caries result from destruction of the tooth's outer mineral matrix by acid-forming bacteria found in dental plaques. Early caries begin as surface disruptions where minerals are leached from the teeth resulting in regions of decreased mineral matrix integrity. Visually, these early carious regions appear as white spots due to the higher backscattering of incident light. With age these areas may become stained by organic compounds. Optical coherence tomography (OCT) examination of human teeth demonstrates a difference in penetration depth of the OCT signal into the carious region in comparison with sound enamel. However, while OCT demonstrates a structural difference in the enamel in the region of the caries, this technique provides little insight into the source of this difference. Raman spectroscopy provides biochemical measures derived from hydroxyapatite within the enamel as well as information on the crystallinity of the enamel matrix. The differences in the biochemical and morphological features of early caries and intact sound enamel are compared. Histological thin sections confirm the observations by OCT morphological imaging while Raman spectroscopy allows for biochemical identification of carious regions by a non-destructive method. Visual examination and conventional radiographic imaging of the intact tooth are used in clinical assessment prior to optical measurements. The combination of OCT, Raman spectroscopy and thin section histology aid in determining the changes that give rise to the visual white spot lesions.

  6. Update on early childhood caries since the Surgeon General's Report.

    PubMed

    Tinanoff, Norman; Reisine, Susan

    2009-01-01

    The 2000 Surgeon General's Report on Oral Health included a limited discussion of the condition known as early childhood caries. Because of its high prevalence, its impact on young children's quality of life and potential for increasing their risk of caries in the permanent dentition, early childhood caries is arguably one of the most serious and costly health conditions among young children. A necessary first step in preventing dental caries in preschool children is understanding and evaluating the child's caries risk factors. Previous caries experience and white spot lesions should automatically classify a preschool child as high risk for caries. Microbial factors, such as presence of visible plaque and tests that identify a child as having high levels of mutans streptococci, also predict caries in young children. Frequency of sugar consumption, enamel developmental defects, social factors such as socioeconomic status, psychosocial factors, and being an ethnic minority also have shown to be relevant in determining caries risk. On the basis of this knowledge of specific risk factors for an individual, different preventive strategies and different intensities of preventive therapies can be implemented. Caries preventive strategies in preschool children include fluoride therapy, such as supervised tooth brushing with a fluoridated dentifrice, systemic fluoride supplement to children who live in a nonfluoridated area and who are at risk for caries, and professional topical fluoride with fluoride varnish. There is emerging evidence that intensive patient counseling or motivational interviews with parents to change specific behaviors may reduce caries prevalence in their children. Findings regarding antimicrobial interventions, efforts to modify diets, and traditional dental health education are less consistent.

  7. Caries risk assessment in schoolchildren - a form based on Cariogram® software

    PubMed Central

    CABRAL, Renata Nunes; HILGERT, Leandro Augusto; FABER, Jorge; LEAL, Soraya Coelho

    2014-01-01

    Identifying caries risk factors is an important measure which contributes to best understanding of the cariogenic profile of the patient. The Cariogram® software provides this analysis, and protocols simplifying the method were suggested. Objectives The aim of this study was to determine whether a newly developed Caries Risk Assessment (CRA) form based on the Cariogram® software could classify schoolchildren according to their caries risk and to evaluate relationships between caries risk and the variables in the form. Material and Methods 150 schoolchildren aged 5 to 7 years old were included in this survey. Caries prevalence was obtained according to International Caries Detection and Assessment System (ICDAS) II. Information for filling in the form based on Cariogram® was collected clinically and from questionnaires sent to parents. Linear regression and a forward stepwise multiple regression model were applied to correlate the variables included in the form with the caries risk. Results Caries prevalence, in primary dentition, including enamel and dentine carious lesions was 98.6%, and 77.3% when only dentine lesions were considered. Eighty-six percent of the children were classified as at moderate caries risk. The forward stepwise multiple regression model result was significant (R2=0.904; p<0.00001), showing that the most significant factors influencing caries risk were caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources. Conclusion The use of the form based on the Cariogram® software enabled classification of the schoolchildren at low, moderate and high caries risk. Caries experience, oral hygiene, frequency of food consumption, sugar consumption and fluoride sources are the variables that were shown to be highly correlated with caries risk. PMID:25466473

  8. Investigation of acid-etched CO2 laser ablated enamel surfaces using polarization sensitive optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Nahm, Byung J.; Kang, Hobin; Chan, Kenneth; Fried, Daniel

    2012-01-01

    A carbon dioxide laser operating at the highly absorbed wavelength of 9.3μm with a pulse duration of 10-15μs is ideally suited for caries removal and caries prevention. The enamel thermally modified by the laser has enhanced resistance to acid dissolution. This is an obvious advantage for caries prevention; however, it is often necessary to etch the enamel surface to increase adhesion to composite restorative materials and such surfaces may be more resistant to etching. The purpose of the study was to non-destructively measure the susceptibility of laser-ablated enamel surfaces to acid dissolution before and after acid-etching using Polarization Sensitive Optical Coherence Tomography (PS-OCT). PS-OCT was used to acquire images of bovine enamel surfaces after exposure to laser irradiation at ablative fluence, acid-etching, and a surface softened dissolution model. The integrated reflectivity from lesion and the lesion depth were measured using PS-OCT. Samples were also sectioned for examination by Polarized Light Microscopy (PLM). PS-OCT images showed that acid-etching greatly accelerated the formation of subsurface lesions on both laser-irradiated and non-irradiated surfaces (P<0.05). A 37.5% phosphoric acid etch removed the laser modified enamel layer after 5-10 seconds.

  9. In-vivo quantification of natural incipient caries lesions using the quantitative light-induced fluoroscence method: a reproducibility study

    NASA Astrophysics Data System (ADS)

    Tranaeus, Sofia; Shi, Xie-Qi; Trollsas, Karin; Lindgren, Lars-Erik; Angmar-Mansson, Birgit

    2000-03-01

    A new method for detection and quantification of natural incipient caries lesions, the Quantitative Light-induced Fluorescence method (QLF), has recently been developed. The aim of this study was to test the repeatability and reproducibility of the analytical part of the method. In vivo captured images (CCD-video camera, Panasonic WV-KS 152, with an argon ion laser as light source) of 15 different incipient caries lesions on smooth surfaces were analyzed by three analysts. The images were analyzed three times in a randomized order, twice for the first reconstructed area (P1A1 and P1A2), and then once for a second one (P2A1). Three parameters were measured, lesion area (mm2), average change in fluorescence (%), and maximum change in fluorescence (%) in the lesion. Repeated measures ANOVA were used to calculate the intra-, and inter-examiner reliability. Intra-examiner reliability for all three analysts showed an intra-class correlation coefficient, R, between 0.93 and 0.99 (for the analyses with the first patch, P1A1 and P1A2, as well as between the first and the second patch, P1A1 and P2A1). Inter-examiner reliability showed an inter-class correlation coefficient, R, between 0.95 and 0.99 (for analyses P1A1, P1A2 and P2A1). It was concluded that the Quantitative Light- induced fluorescence method showed excellent repeatability and reproducibility concerning the analytical part of the method.

  10. Need for new caries detection methods

    NASA Astrophysics Data System (ADS)

    Young, Douglas A.; Featherstone, John D. B.

    1999-05-01

    Dental caries (tooth decay) continues to be a major problems for adults as well as children, even though great advances have been made in preventive methods in the last 20 years. New methods for the management of caries will work best if lesions can be detected at an early stage and chemical rather than physical intervention can take place, thereby preserving the natural tooth structure and helping the saliva to heal, or remineralize, the areas of early decay. Clinical detection of caries in the US relies on visual examination, tactile with hand held explorer, and conventional radiographs, all of which are inadequate for the occlusal (biting) surfaces of the teeth where most of the decay now occurs. The dentist often has to explore by drilling with a dental bur to confirm early decay in these areas. New method that can determine the extent and degree of subsurface lesions in these surfaces non-destructively are essential for further advances in the clinical management of dental caries. Optical methods, which exploit the differences between sound and carious enamel and dentin, show great promise for the accurate detection of these lesions. Two or three- dimensional images, which include a measure of severity will be needed.

  11. Early diagnosis of incipient caries based on non-invasive lasers

    NASA Astrophysics Data System (ADS)

    Velescu, A.; Todea, C.; Vitez, B.

    2016-03-01

    AIM: The aim of this study is to detect incipient caries and enamel demineralization using laser fluorescence.This serves only as an auxilary aid to identify and to monitor the development of these lesions. MATERIALS AND METHODS: 6 patients were involved in this study, three females and three male. Each patient underwent a professional cleaning, visual examination of the oral cavity, and then direct inspection using DiagnoCam and DIAGNOdent. After data recording each patient was submitted to retro-alveolar X-ray on teeth that were detected with enamel lesions. All data was collected and analyzed statistically. RESULTS: Of 36 areas considered in clinically healthy, 24 carious surfaces were found using laser fluorescence, a totally non-invasive method for detecting incipient carious lesions compared with the radiographic examination. CONCLUSIONS: This method has good applicability for patients because it improves treatment plan by early detection of caries and involves less fear for anxious patients and children.

  12. Update on Early Childhood Caries since the Surgeon General's Report

    PubMed Central

    Tinanoff, Norman; Reisine, Susan

    2009-01-01

    The 2000 Surgeon General's Report on Oral Health (SGROH) included a limited discussion of the condition known as Early Childhood Caries (ECC). Because of its high prevalence, its impact on young children's quality of life and potential for increasing their risk of caries in the permanent dentition, ECC is arguably one of the most serious and costly health conditions among young children. A necessary first step in preventing dental caries in preschool children is understanding and evaluating the child's caries risk factors. Previous caries experience and white spot lesions should automatically classify a preschool child as high risk for caries. Microbial factors, such as presence of visible plaque and tests that identify a child as having high levels of mutans streptococci also predict caries in young children. Frequency of sugar consumption, enamel developmental defects, social factors such as socioeconomic status, psychosocial factors, and being an ethnic minority also have shown to be relevant in determining caries risk. Based on this knowledge of specific risk factors for an individual, different preventive strategies as well as different intensities of preventive therapies can be employed. Caries preventive strategies in preschool children include fluoride therapy, such as supervised tooth brushing with fluoridated dentifrice, systemic fluoride supplement to children living in a non-fluoridated area that are at risk for caries, and professional topical fluoride with fluoride varnish. There is emerging evidence that intensive patient counseling or motivational interviews with parents to change specific behaviors may reduce caries prevalence in their children. Findings regarding antimicrobial interventions, efforts to modify diets, and traditional dental health education are less consistent. PMID:19945074

  13. [Comparison of reproducibility measurements for calibration of dental caries epidemiological surveys].

    PubMed

    Assaf, Andréa Videira; Zanin, Luciane; Meneghim, Marcelo de Castro; Pereira, Antonio Carlos; Ambrosano, Gláucia Maria Bovi

    2006-09-01

    This study compares three measurements (Kappa, general agreement percentage, or GAP, and dice index) used to determine the reproducibility of caries diagnosis in epidemiological surveys under different clinical diagnostic thresholds. Eleven examiners with previous experience in epidemiological surveys were submitted to a theoretical and clinical calibration process. Data analysis used two caries detection thresholds: World Health Organization (WHO) and WHO with the inclusion of initial enamel lesions (WHO + IL). Twenty-three children 6-7 years of age were examined, with and without caries. Mean values for Kappa index, GAP, and Dice were considered high (> 0.90), except for the dice index for the WHO + IL threshold (0.69). Since Kappa is an adjusted agreement index, it can be considered the instrument of choice for calibration of examiners. However, when it is impossible to use, the GAP is recommended together with the dice index in order to orient and improve examiners when examining caries lesions.

  14. Aquaporin 5 Interacts with Fluoride and Possibly Protects against Caries

    PubMed Central

    Deeley, Kathleen; Poletta, Fernardo A.; Mereb, Juan C.; Leite, Aline L.; Barreta, Priscila A. T. M.; Silva, Thelma L.; Dizak, Piper; Ruff, Timothy; Patir, Asli; Koruyucu, Mine; Abbasoğlu, Zerrin; Casado, Priscila L.; Brown, Andrew; Zaky, Samer H.; Bayram, Merve; Küchler, Erika C.; Cooper, Margaret E.; Liu, Kai; Marazita, Mary L.; Tanboğa, İlknur; Granjeiro, José M.; Seymen, Figen; Castilla, Eduardo E.; Orioli, Iêda M.; Sfeir, Charles; Owyang, Hongjiao; Buzalaf, Marília A. R.; Vieira, Alexandre R.

    2015-01-01

    Aquaporins (AQP) are water channel proteins and the genes coding for AQP2, AQP5, and AQP6 are clustered in 12q13. Since AQP5 is expressed in serous acinar cells of salivary glands, we investigated its involvement in caries. DNA samples from 1,383 individuals from six groups were studied. Genotypes of eight single nucleotide polymorphisms covering the aquaporin locus were tested for association with caries experience. Interaction with genes involved in enamel formation was tested. The association between enamel microhardness at baseline, after creation of artificial caries lesion, and after exposure to fluoride and the genetic markers in AQP5 was tested. Finally, AQP5 expression in human whole saliva, after exposure to fluoride in a mammary gland cell line, which is known to express AQP5, and in Wistar rats was also verified. Nominal associations were found between caries experience and markers in the AQP5 locus. Since these associations suggested that AQP5 may be inhibited by levels of fluoride in the drinking water that cause fluorosis, we showed that fluoride levels above optimal levels change AQP5 expression in humans, cell lines, and rats. We have shown that AQP5 is involved in the pathogenesis of caries and likely interacts with fluoride. PMID:26630491

  15. Effect of CPP-ACP paste on dental caries in primary teeth: a randomized trial.

    PubMed

    Sitthisettapong, T; Phantumvanit, P; Huebner, C; Derouen, T

    2012-09-01

    This clinical trial tested the effect of daily application of 10% w/v calcium phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste for 1 yr when added to regular toothbrushing with fluoridated toothpaste to prevent dental caries in pre-school children. High-caries-risk children aged 2½ to 3½ yrs in a suburban area of central Thailand were assigned to receive either CPP-ACP (n = 150) or a placebo control (n = 146) in addition to fluoridated toothpaste. The International Caries Detection and Assessment System (ICDAS) was recorded at baseline, 6 mos, and 1 yr. At 1 yr, a significant increase in mean numbers of enamel and dentin caries lesions, as well as dmfs, was found in both groups (p < 0.001). No significant difference was observed between groups on these 3 outcome measures (p = 0.23, 0.84, and 0.91, respectively). The odds of enamel caries lesion transitions to a state of regression or stability, compared with progression from baseline, was also not different between groups [OR = 1.00, 95% CI (0.86, 1.17)]. This trial found that daily application of 10% w/v CPP-ACP paste on school days for 1 yr, when added to regular toothbrushing with a fluoride toothpaste, had no significant added effect in preventing caries in the primary dentition of these pre-school children (ClinicalTrials.gov number CT01 604109).

  16. New method to detect caries via fluorescence

    NASA Astrophysics Data System (ADS)

    Eberhart, J.; Frentzen, M.; Thoms, M.

    2007-07-01

    Caries, a common and widespread infectious disease, has to be detected as early as possible. Based on the need for an easy and handy tool for preventing invasive treatment a new fluorescence camera system has been developed. Using this camera the so-called porphyrins, metabolic products of oral pathogenic bacteria can be visualized. Thereby fluorophores are excited at a wavelength of 405nm by the built-in GaN-LEDs. Healthy and diseased dental hard tissues fluoresce in the green and in the red spectral range, respectively, thus allowing differentiation by coulor. To prove the reliability of this fluorescence camera system, freshly extracted teeth were examined. Three different methods of analysis were verified and compared to give information about the lesions (sensitivity & selectivity): The extent of the fluorescence area, the integral of the red/green ratio of the lesion and the maximum red/green ratio in the area of interest. Histological sections of the teeth served as reference. In addition, the camera was compared to a tip probe sensor already available on the market. In total, our results show that regarding the three different algorithms of analysis, the maximum of the red/green ratio is a preferential method to evaluate carious lesions. Sound tissue, enamel caries and dentin caries can be clearly distinguished. The new fluorescence camera is a handy, efficient and fast device in order to detect lesions and seems to be superior to the tip probe sensor regarding the positioning. Further studies are required.

  17. Image-guided removal of occlusal caries lesions with a λ= 9.3-μm CO2 laser using near-IR transillumination

    NASA Astrophysics Data System (ADS)

    Chung, Leon C.; Tom, Henry; Chan, Kenneth H.; Simon, Jacob C.; Fried, Daniel; Darling, Cynthia L.

    2015-02-01

    Previous studies have shown that near-IR transillumination is well suited for imaging deep occlusal lesions. The purpose of this study was to determine if near-IR images can be used to guide a CO2 laser for the selective removal of natural occlusal lesions on extracted teeth. Near-IR occlusal transillumination images of extracted human teeth with natural occlusal caries lesions were acquired using an InGaAs camera and near-IR light at wavelengths from 1290 to 1470-nm from a filtered tungsten halogen source. A CO2 laser operating at 9.3-μm with a pulse duration of 10-15-μs and a pulse repetition rate of 100-300-Hz was used for caries removal. Optical Coherence tomography was used to confirm lesion presence and serial scans were used to assess selective removal. Teeth were also sectioned for histological examination using polarized light microscopy. This study suggests that near-infrared transillumination is a promising method for the image guided laser ablation of occlusal caries lesions but the use of serial near-IR transillumination imaging for monitoring lesion removal was limited.

  18. Enamel bevelling and retention of composite restorations in non-carious cervical lesions.

    PubMed

    Ahmed, Khaled

    2016-09-01

    Data sourcesMedline, Web of Science, Latin American and Caribbean Health Sciences Literature database (LILACS), Brazilian Library in Dentistry (BBO), the Cochrane Library, abstracts of the annual conference of the International Association for Dental Research (IADR), System for Information on Grey literature in Europe (SIGLE), ProQuest Dissertations and Theses Fulltext database as well as the Periódicos Capes Theses, Current Controlled Trials, International Clinical trials registry platform, the ClinicalTrials.gov, Rebec and the EU Clinical Trials Register.Study selectionRandomised clinical trials (RCTs) that compared the retention rates of restorations in NCCLs placed with or without bevel with at least one year follow-up were considered.Data extraction and synthesisData were abstracted using standardised forms and study quality was assessed using the Cochrane risk of bias tool. Marginal discolouration scores were dichotomised into yes and no, and risk differences for retention rate and marginal discolouration were calculated for each study for analysis.ResultsFour studies were included. Two studies were considered to be at high risk of bias and not included in the meta-analysis. The overall risk difference was 0.0 (95%CI; 0.04 to 0.04) for the retention rate and 0.05 ((95%CI; 0.02 to 0.13) for the marginal discolouration, suggesting that enamel beveling does not influence retention rate or marginal discolouration.ConclusionsOne may conclude that there is no difference between bevelled and non-bevelled technique over the short-term follow-up of 12-18 months of clinical service, although this conclusion was based on only two low risk of bias RCTs. Additionally, there is not enough evidence to support this conclusion over longer-term follow-ups. There is a need for better standardisation and the reporting of RCTs investigating this technique variation after longer-term follow-up periods.

  19. Fluorine analysis of human enamel around fluoride-containing materials under different pH-cycling by μ-PIGE/PIXE system

    NASA Astrophysics Data System (ADS)

    Komatsu, H.; Yamamoto, H.; Matsuda, Y.; Kijimura, T.; Kinugawa, M.; Okuyama, K.; Nomachi, M.; Yasuda, K.; Satoh, T.; Oikawa, S.

    2011-10-01

    The caries preventive effect of fluoride-containing materials (FCMs) might depend on the caries risk of the individuals. Two pairs of demineralizing and remineralizing solutions of pH-cycling were prepared for simulating low and high caries risk. The purpose of this study was to determine fluorine (F) uptake into human enamel around FCMs under different pH-cycling using the in-air μ-PIGE/PIXE system. Fluoride-containing glass ionomer cement (Fuji IXGP FAST CAPSULE (FN)), and composite resin (BEAUTIFIL II with FLUORO BOND SHAKE ONE (BS)) were used in this study. The pH-cycling (pH 6.8-4.5) was carried out for 5 weeks. After pH-cycling, the caries progression was analyzed using transverse micro-radiography (TMR). The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the PIGE/PIXE system. From TMR analysis, there was a difference in caries risk between the two kinds of pH-cycling. Although the caries preventive effect of BS and FN was confirmed at low risk, the effect at high risk was confirmed for FN only. From the analysis of the fluorine uptake in the outer 200 μm of the lesion we concluded that there was no significant difference between the pH-cycling solutions. However, we found different fluorine concentrations in the enamel for the two FCMs. The decreased caries progression under high risk for FN indicated that an adequate amount of fluorine supplied from the material is required at higher caries risk. It was confirmed that the caries preventive effect of FCM depends on the caries risk. The fluorine analysis of teeth under various pH-cycling conditions gives information to evaluate the caries preventive effect of fluoride-containing materials according to the caries risk.

  20. Treatment of deep caries lesions in adults: randomized clinical trials comparing stepwise vs. direct complete excavation, and direct pulp capping vs. partial pulpotomy.

    PubMed

    Bjørndal, Lars; Reit, Claes; Bruun, Gitte; Markvart, Merete; Kjaeldgaard, Marianne; Näsman, Peggy; Thordrup, Marianne; Dige, Irene; Nyvad, Bente; Fransson, Helena; Lager, Anders; Ericson, Dan; Petersson, Kerstin; Olsson, Jadranka; Santimano, Eva M; Wennström, Anette; Winkel, Per; Gluud, Christian

    2010-06-01

    Less invasive excavation methods have been suggested for deep caries lesions. We tested the effects of stepwise vs. direct complete excavation, 1 yr after the procedure had been carried out, in 314 adults (from six centres) who had received treatment of a tooth with deep caries. The teeth had caries lesions involving 75% or more of the dentin and were centrally randomized to stepwise or direct complete excavation. Stepwise excavation resulted in fewer pulp exposures compared with direct complete excavation [difference: 11.4%, 95% confidence interval (CI) (1.2; 21.3)]. At 1 yr of follow-up, there was a statistically significantly higher success rate with stepwise excavation, with success being defined as an unexposed pulp with sustained pulp vitality without apical radiolucency [difference: 11.7%, 95% CI (0.5; 22.5)]. In a subsequent nested trial, 58 patients with exposed pulps were randomized to direct capping or partial pulpotomy. We found no significant difference in pulp vitality without apical radiolucency between the two capping procedures after more than 1 yr [31.8% and 34.5%; difference: 2.7%, 95% CI (-22.7; 26.6)]. In conclusion, stepwise excavation decreases the risk of pulp exposure compared with direct complete excavation. In view of the poor prognosis of vital pulp treatment, a stepwise excavation approach for managing deep caries lesions is recommended.

  1. Efficacy of amelogenin-chitosan hydrogel in biomimetic repair of human enamel in pH-cycling systems

    PubMed Central

    Ruan, Qichao; Liberman, David; Bapat, Rucha; Chandrababu, Karthik Balakrishna; Phark, Jin-Ho; Moradian-Oldak, Janet

    2016-01-01

    Amelogenin-chitosan (CS-AMEL) hydrogel has shown great potential for the prevention, restoration, and treatment of defective enamel. As a step prior to clinical trials, this study aimed to examine the efficacy of CS-AMEL hydrogel in biomimetic repair of human enamel with erosive or caries-like lesions in pH-cycling systems. Two models for enamel defects, erosion and early caries, were addressed in this study. Two pH-cycling systems were designed to simulate the daily cariogenic challenge as well as the nocturnal pH conditions in the oral cavity. After pH cycling and treatment with CS-AMEL hydrogel, a synthetic layer composed of oriented apatite crystals was formed on the eroded enamel surface. CS-AMEL repaired the artificial incipient caries by re-growing oriented crystals and reducing the depth of the lesions by up to 70% in the pH-cycling systems. The results clearly demonstrate that the CS-AMEL hydrogel is effective at the restoration of erosive and carious lesions under pH-cycling conditions. PMID:27331142

  2. Weaker dental enamel explains dental decay.

    PubMed

    Vieira, Alexandre R; Gibson, Carolyn W; Deeley, Kathleen; Xue, Hui; Li, Yong

    2015-01-01

    Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is "weaker" while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution.

  3. Dental caries detection by optical spectroscopy: a polarized Raman approach with fibre-optic coupling

    NASA Astrophysics Data System (ADS)

    Ko, A. C.-T.; Choo-Smith, L.-P.; Werner, J.; Hewko, M.; Sowa, M. G.; Dong, C.; Cleghorn, B.

    2006-09-01

    Incipient dental caries lesions appear as white spots on the tooth surface; however, accurate detection of early approximal lesions is difficult due to limited sensitivity of dental radiography and other traditional diagnostic tools. A new fibre-optic coupled spectroscopic method based on polarized Raman spectroscopy (P-RS) with near-IR laser excitation is introduced which provides contrast for detecting and characterizing incipient caries. Changes in polarized Raman spectra are observed in PO 4 3- vibrations arising from hydroxyapatite of mineralized tooth tissue. Demineralization-induced morphological/orientational alteration of enamel crystallites is believed to be responsible for the reduction of Raman polarization anisotropy observed in the polarized Raman spectra of caries lesions. Supporting evidence obtained by polarized Raman spectral imaging is presented. A specially designed fibre-optic coupled setup for simultaneous measurement of parallel- and cross-polarized tooth Raman spectra is demonstrated in this study.

  4. Effect of fluoride, lesion baseline severity and mineral distribution on lesion progression.

    PubMed

    Lippert, F; Butler, A; Lynch, R J M; Hara, A T

    2012-01-01

    The present study investigated the effects of fluoride (F) concentration, lesion baseline severity (ΔZ(base)) and mineral distribution on lesion progression. Artificial caries lesions were created using three protocols [methylcellulose acid gel (MeC), hydroxyethylcellulose acid gel (HEC), carboxymethylcellulose acid solution (CMC)] and with low and high ΔZ(base) groups by varying demineralization times within protocols. Subsequently, lesions were immersed in a demineralizing solution for 24 h in the presence of 0, 1, 2 or 5 ppm F. Changes in mineral distribution characteristics of caries lesions were studied using transverse microradiography. At baseline, the protocols yielded lesions with three distinctly different mineral distributions. Secondary demineralization revealed differences in F response between and within lesion types. In general, lowΔZ lesions were more responsive to F than highΔZ lesions. LowΔZ MeC lesions showed the greatest range of response among all lesions, whereas highΔZ HEC lesions were almost unaffected by F. Laminations were observed in the presence of F in all but highΔZ HEC and CMC lesions. Changes in mineral distribution effected by F were most pronounced in MeC lesions, with remineralization/mineral redeposition in the original lesion body at the expense of sound enamel beyond the original lesion in a dose-response manner. Both ΔZ(base) and lesion mineral distribution directly impact the F response and the extent of secondary demineralization of caries lesions. Further studies - in situ and on natural white spot lesions - are required to better mimic in vivo caries under laboratory conditions.

  5. Optical Coherence Tomography as an Auxiliary Tool for the Screening of Radiation-Related Caries

    PubMed Central

    de Oliveira Mota, Cláudia Cristina Brainer; Maia, Ana Marly Araújo; Santos-Silva, Alan Roger; Gomes, Anderson Stevens Leonidas; de Abreu Alves, Fábio; Leão, Jair Carneiro; de Freitas, Anderson Zanardi; Goes, Mário; Lopes, Márcio Ajudarte

    2013-01-01

    Abstract Objective: The aim of this study was to evaluate the morphological alterations of radiation-related caries using optical coherence tomography. Methods: Thirty-six extracted teeth from 11 patients who had undergone radiotherapy were sectioned in the sagittal axis in the center of the carious lesion, and 100 μm thick sections were obtained from each specimen. One sample from each tooth was investigated by an optical coherence tomography (OCT) system, and the results were compared with histological images from polarized light microscopy. Results: In OCT dentin caries images, the demineralized area appeared as a white region, whereas the translucent zone appeared as a dark area, a similar pattern also seen in coronal caries. In noncavitated enamel lesions clinically observed as brown discoloration, the area of high porosity, and also the dark color, absorbs part of the light, resulting in a dark pattern. Finally, the involvement of dentin–enamel junction (DEJ) or cement–enamel junction (CEJ) could be clearly observed, when present and marked alterations along the CEJ could be noted, as junction continuity loss, gap formation, and mineral loss tissue. Conclusions: The OCT technique was able to characterize radiation-related caries, from a morphological point of view. Also demonstrated was its potential benefit for use in the clinical monitoring of radiation-related carious process. PMID:23819504

  6. Accuracy of direct digital radiography for detecting occlusal caries in primary teeth compared with conventional radiography and visual inspection: an in vitro study

    PubMed Central

    Dias da Silva, P R; Martins Marques, M; Steagall, W; Medeiros Mendes, F; Lascala, C A

    2010-01-01

    Objectives The diagnosis of caries lesions is still a matter of concern in dentistry. The diagnosis of dental caries by digital radiography has a number of advantages over conventional radiography; however, this method has not been explored fully in the field of paediatric dentistry. This in vitro research evaluated the accuracy of direct digital radiography compared with visual inspection and conventional radiography in the diagnosis of occlusal caries lesions in primary molars. Methods 50 molars were selected and evaluated under standardized conditions by 2 previously calibrated examiners according to 3 diagnostic methods (visual inspection, conventional radiography and direct digital radiography). Direct digital radiographs were obtained with the Dixi3 system (Planmeca, Helsinki, Finland) and the conventional radiographs with InSight film (Kodak Eastman Co., Rochester, NY). The images were scored and a reference standard was obtained histologically. The interexaminer reliability was calculated using Cohen's kappa test and the specificity, sensitivity and accuracy of the methods were calculated. Results Examiner reliability was good. For lesions limited to the enamel, visual inspection showed significantly higher sensitivity and accuracy than both radiographic methods, but no significant difference was found in specificity. For teeth with dentinal caries, no significant differences were found for any parameter when comparing visual and radiographic evaluation. Conclusions Although less accurate than the visual method for detecting caries lesions confined to the enamel, the direct digital radiographic method is as effective as conventional radiographic examination and visual inspection of primary teeth with occlusal caries when the dentine is involved. PMID:20729186

  7. Comparison of reflectance spectra of sound and carious enamel

    NASA Astrophysics Data System (ADS)

    Analoui, Mostafa; Ando, Masatoshi; Stookey, George K.

    2000-03-01

    Development of dental caries is associated with the loss of minerals and change in the enamel structure. In this study, we have measured and compared reflectance spectra of sound and carious enamel, to investigate its utility in detection and analysis of dental caries. One hundred twenty, 3-mm diameter human enamel cores, with no sign of fluorosis, tetracycline stain, hypoplasia, fracture and restorations, were prepared. The enamel surfaces then were ground and polished. Specimens were placed on a fitted holder with either black or white color for background, with no fluorescence. The baseline spectra were measured using a spectrophotometer with enclosed diffused illumination. Spectra measured from 380 to 780 nm at 5 nm intervals. All measurements were corrected to compensate for the spectrum of illumination. The specimens were divided into two groups and exposed to a demineralizing solution, for 48 and 96 hours, respectively. Reflectance spectra of specimens were measured following lesion induction. All specimens were sectioned and analyzed by transverse microradiography (TMR), where lesion depth and mineral loss ((Delta) Z) were measured. Dimensionality of multi-spectral data was reduced through its conversion to L*a*b* color coordinates and principal component analysis (PCA). Multiple linear regression analysis showed low correlation between L*a*b* and lesion depth and mineral loss. PCA analysis showed higher correlation coefficient, compared to L*a*b*. Preliminary results of this study suggest that multi-spectral measurement and analysis of the tooth surface could be useful in predicting the depth and severity of an early carious lesion.

  8. Evidence of an in vitro Coupled Diffusion Mechanism of Lesion Formation within Microcosm Dental Plaque.

    PubMed

    Owens, Gareth J; Lynch, Richard J M; Hope, Christopher K; Cooper, Lee; Higham, Susan M; Valappil, Sabeel P

    2017-03-01

    The purpose of this study was to determine whether or not the dual constant-depth film fermenter (dCDFF) is able to produce caries-like enamel lesions and to ascertain further information regarding the performance of this fully functional biological caries model. Conditions were defined by the continuation (CF) or cessation (FF) of a saliva-type growth medium supply during 50-mM sucrose exposures (8 times daily). Hydroxyapatite (n = 3) and bovine enamel (n = 3) substrata were included within each condition and samples extracted after 2, 4, 8, and 16 days. Community profiles were generated for fastidious anaerobes, Lactobacillus spp., Streptococcus spp., mutans streptococci (MS), and Veillonella spp. using selective culture techniques and enamel demineralisation assessed by transverse microradiography. Results demonstrated that the dCDFF model is able to produce caries-like enamel lesions with a high degree of sensitivity where reduced ionic strength within the FF condition increased surface layer mineral deposition. Between conditions, biofilm communities did not differ significantly, although MS in the biofilms extracted from the FF condition rose to a higher proportion (by 1.5 log10 units), and Veillonella spp. were initially greater within the CF condition (by 2.5 log10 units), indicating an enhanced ability for the clearance of low-pKa acids following exposures to sucrose. However, both conditions retained the ability for caries-like lesion formation.

  9. Evaluation of new treatment for incipient enamel demineralization using 45S5 bioglass.

    PubMed

    Bakry, A S; Takahashi, H; Otsuki, M; Tagami, J

    2014-03-01

    Bioglass 45S5 is a silica-based bioactive glass capable of depositing a layer of hydroxyl carbonate apatite on the surface of the glass when immersed in body fluids. The present paper studies a new technique for treating early human dental enamel caries lesions by using a paste composed of 45S5 bioglass and phosphoric acid. Artificial caries lesions were induced in enamel flat surfaces by means of a decalcification solution. All specimens were exposed to a brushing-abrasion challenge to test the durability of any newly formed layer resulting from the application of 45S5 bioglass paste. The specimens treated with bioglass paste showed complete coverage with a layer of brushite crystals. The brushing-abrasion challenge did not statistically affect the percentage of enamel coverage with the crystalline layer formed by the application of bioglass (p<0.05). These crystals were converted to hydroxyapatite crystals when stored in artificial saliva for 14 days. The current technique suggests the possibility of restoring incipient enamel erosive lesion with an abrasion durable layer of hydroxyapatite crystals.

  10. Multimodal optical device for early childhood caries: a clinical prototype

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Ridge, Jeremy S.; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    There is currently a need for a safe and effective way to detect and diagnose early childhood caries. We have developed a multimodal optical clinical prototype for testing in vivo. The device can be used to quickly image and screen for any signs of demineralized enamel by obtaining high-resolution and highcontrast surface images using a 405-nm laser as the illumination source, as well as obtaining autofluorescence and bacterial fluorescence images. Then, when a suspicious region is located, the device can perform dual laser fluorescence spectroscopy using 405-nm and 532-nm laser excitation which is used to compute an autofluorescence ratio. This ratio can be used to quantitatively diagnose enamel health. The device is tested on four in vivo test subjects as well as 17 extracted teeth with clinically diagnosed carious lesions. The device was able to provide detailed images which served to screen for suspected early caries. The autofluorescence ratios obtained from the extracted teeth were able to discriminate between healthy and unhealthy enamel. Therefore, the clinical prototype demonstrates feasibility in screening for and in quantitatively diagnosing healthy from demineralized enamel.

  11. Detection of occlusal caries in primary teeth using swept source optical coherence tomography.

    PubMed

    Nakajima, Yukie; Shimada, Yasushi; Sadr, Alireza; Wada, Ikumi; Miyashin, Michiyo; Takagi, Yuzo; Tagami, Junji; Sumi, Yasunori

    2014-01-01

    This study aimed to investigate swept source optical coherence tomography (SS-OCT) as a detecting tool for occlusal caries in primary teeth. At the in vitro part of the study, 38 investigation sites of occlusal fissures (noncavitated and cavitated) were selected from 26 extracted primary teeth and inspected visually using conventional dental equipment by six examiners without any magnification. SS-OCT cross-sectional images at 1330-nm center wavelength were acquired on the same locations. The teeth were then sectioned at the investigation site and directly viewed under a confocal laser scanning microscope (CLSM) by two experienced examiners. The presence and extent of caries were scored in each observation. The results obtained from SS-OCT and conventional visual inspections were compared with those of CLSM. Consequently, SS-OCT could successfully detect both cavitated and noncavitated lesions. The magnitude of sensitivity for SS-OCT was higher than those for visual inspection (sensitivity of visual inspection and SS-OCT, 0.70 versus 0.93 for enamel demineralization, 0.49 versus 0.89 for enamel cavitated caries, and 0.36 versus 0.75 for dentin caries). Additionally, occlusal caries of a few clinical cases were observed using SS-OCT in vivo. The results indicate that SS-OCT has a great detecting potential for occlusal caries in primary teeth.

  12. Detection of occlusal caries in primary teeth using swept source optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Nakajima, Yukie; Shimada, Yasushi; Sadr, Alireza; Wada, Ikumi; Miyashin, Michiyo; Takagi, Yuzo; Tagami, Junji; Sumi, Yasunori

    2014-01-01

    This study aimed to investigate swept source optical coherence tomography (SS-OCT) as a detecting tool for occlusal caries in primary teeth. At the in vitro part of the study, 38 investigation sites of occlusal fissures (noncavitated and cavitated) were selected from 26 extracted primary teeth and inspected visually using conventional dental equipment by six examiners without any magnification. SS-OCT cross-sectional images at 1330-nm center wavelength were acquired on the same locations. The teeth were then sectioned at the investigation site and directly viewed under a confocal laser scanning microscope (CLSM) by two experienced examiners. The presence and extent of caries were scored in each observation. The results obtained from SS-OCT and conventional visual inspections were compared with those of CLSM. Consequently, SS-OCT could successfully detect both cavitated and noncavitated lesions. The magnitude of sensitivity for SS-OCT was higher than those for visual inspection (sensitivity of visual inspection and SS-OCT, 0.70 versus 0.93 for enamel demineralization, 0.49 versus 0.89 for enamel cavitated caries, and 0.36 versus 0.75 for dentin caries). Additionally, occlusal caries of a few clinical cases were observed using SS-OCT in vivo. The results indicate that SS-OCT has a great detecting potential for occlusal caries in primary teeth.

  13. Dental caries in Rome, 50-100 AD.

    PubMed

    Fejerskov, O; Guldager Bilde, P; Bizzarro, M; Connelly, J N; Skovhus Thomsen, J; Nyvad, B

    2012-01-01

    Scarce information exists on the clinical features of dental caries in the Imperial Roman population and no structural data on caries lesions from this period have so far been published. We report on the findings of 86 teeth (50-100 AD) found during archaeological excavations of the temple of Castor and Pollux in the Forum Romanum. We found that nearly all teeth had large carious cavities extending into the pulp. The distribution and size of the caries lesions were similar to those found in contemporary adult populations in Africa and China living without access to dental care. Most lesions had a hypermineralized zone in the dentin at the advancing front of the carious cavities as revealed by micro-computed tomography. This biological dentin reaction combined with the morphology of the cavities might indicate that some temporary topical pain relief and intervention treatment slowed down the rate of lesion progression. This is indirectly supported by examination of cavities of similar size and depth from a contemporary population without access to dental health care. In contrast to the lesions in the Roman teeth, these lesions did not exhibit a hypermineralized dentin reaction. We investigated whether the Pb isotopic composition of enamel and/or dentin of a single tooth matched that of a sample of an ancient Forum water lead pipe. The Pb isotopic composition of the tooth did not match that of the tube, suggesting that the subjects were exposed to different Pb sources during their lifetime other than the lead tubes.

  14. All-optical photoacoustic imaging and detection of early-stage dental caries

    NASA Astrophysics Data System (ADS)

    Sampathkumar, Ashwin; Hughes, David A.; Longbottom, Chris; Kirk, Katherine J.

    2015-02-01

    Dental caries remain one of the most common oral diseases in the world. Current detection methods, such as dental explorer and X-ray radiography, suffer from poor sensitivity and specificity at the earliest (and reversible) stages of the disease because of the small size (< 100 microns) of early-stage lesions. We have developed a fine-resolution (480 nm), ultra-broadband (1 GHz), all-optical photoacoustic imaging (AOPAI) system to image and detect early stages of tooth decay. This AOPAI system provides a non-contact, non-invasive and non-ionizing means of detecting early-stage dental caries. Ex-vivo teeth exhibiting early-stage, white-spot lesions were imaged using AOPAI. Experimental scans targeted each early-stage lesion and a reference healthy enamel region. Photoacoustic (PA) signals were generated in the tooth using a 532-nm pulsed laser and the light-induced broadband ultrasound signal was detected at the surface of the tooth with an optical path-stabilized Michelson interferometer operating at 532 nm. The measured time-domain signal was spatially resolved and back-projected to form 2D and 3D maps of the lesion using k-wave reconstruction methods. Experimental data collected from areas of healthy and diseased enamel indicate that the lesion generated a larger PA response compared to healthy enamel. The PA-signal amplitude alone was able to detect a lesion on the surface of the tooth. However, time- reversal reconstructions of the PA scans also quantitatively depicted the depth of the lesion. 3D PA reconstruction of the diseased tooth indicated a sub-surface lesion at a depth of 0.6 mm, in addition to the surface lesion. These results suggest that our AOPAI system is well suited for rapid clinical assessment of early-stage dental caries. An overview of the AOPAI system, fine-resolution PA and histology results of diseased and healthy teeth will be presented.

  15. Prevalence of Dental Caries among School Children in Chennai, Based on ICDAS II

    PubMed Central

    Arangannal, Ponnudurai; Jayaprakash, Jeevarathan

    2016-01-01

    Introduction Dental caries is a common dental disease, which occurs during childhood and continues to be a major public health problem. The prevalence of dental caries was associated with oral hygiene practice, sugar consumption and implementation of the preventive oral health program. Aim The purpose of this study was to assess the prevalence of dental caries in school children aged between 6-14 years using the International Caries Detection and Assessment System (ICDAS II). Materials and Methods The study population consisted of 2796 school children living in Pallikkaranai, Chennai, India and studying in government recognized schools. Each student was examined by a single examiner using ICDAS system under natural light during normal school hours. Results The prevalence of dental caries was 68.8% in the total surveyed population. The gender-wise prevalence of dental caries shows, females to have slightly higher prevalence than male. The prevalence of dental caries at the age group of 6 years was 57%, seven year 67%, eight year 63%, nine year 74%, 10 year 76%, 11 year 74%, 12 year 69%, 13 year 71%, and 14 year 69%. The distribution of CARS (Caries associated with Sealants and Restorations) in the surveyed population was only 1.4% Conclusion The distribution of non-cavitated/early enamel lesions was higher in the studied population and indicated a requirement of a sustained dental health preventive program targeting specific segments of the population. PMID:27190939

  16. Histological validation of near-infrared reflectance multispectral imaging technique for caries detection and quantification

    NASA Astrophysics Data System (ADS)

    Salsone, Silvia; Taylor, Andrew; Gomez, Juliana; Pretty, Iain; Ellwood, Roger; Dickinson, Mark; Lombardo, Giuseppe; Zakian, Christian

    2012-07-01

    Near infrared (NIR) multispectral imaging is a novel noninvasive technique that maps and quantifies dental caries. The technique has the ability to reduce the confounding effect of stain present on teeth. The aim of this study was to develop and validate a quantitative NIR multispectral imaging system for caries detection and assessment against a histological reference standard. The proposed technique is based on spectral imaging at specific wavelengths in the range from 1000 to 1700 nm. A total of 112 extracted teeth (molars and premolars) were used and images of occlusal surfaces at different wavelengths were acquired. Three spectral reflectance images were combined to generate a quantitative lesion map of the tooth. The maximum value of the map at the corresponding histological section was used as the NIR caries score. The NIR caries score significantly correlated with the histological reference standard (Spearman's Coefficient=0.774, p<0.01). Caries detection sensitivities and specificities of 72% and 91% for sound areas, 36% and 79% for lesions on the enamel, and 82% and 69% for lesions in dentin were found. These results suggest that NIR spectral imaging is a novel and promising method for the detection, quantification, and mapping of dental caries.

  17. Imaging of occlusal dental caries (decay) with near-IR light at 1310-nm

    NASA Astrophysics Data System (ADS)

    Bühler, Christopher M.; Ngaotheppitak, Patara; Fried, Daniel

    2005-01-01

    Dental enamel manifests high transparency in the near-IR. Previous work demonstrated that near-IR light at 1310-nm is ideally suited for the transillumination of interproximal dental caries (dental decay in between teeth) [1]. However, most new dental decay occurs in the pits and fissures of the occlusal (biting) surfaces of posterior teeth. These caries lesions cannot be detected by x-rays during the early stages of decay due to the overlapping topography of the crown of the tooth. In this study, a near- IR imaging system operating at 1310-nm was used to acquire occlusal images by launching the near-IR light into the buccal surface of the tooth just above the gingival margin (gum-line). The near-IR light diffuses through the highly scattering dentin providing uniform back illumination of the enamel of the crowns allowing imaging of the occlusal surfaces. The near-IR images show high contrast between sound and demineralized areas. Demineralization (decay) can be easily differentiated from stains, pigmentation, and hypomineralization (fluorosis). Moreover, the high transparency of the enamel enables imaging at greater depth for the detection of subsurface decay hidden under the enamel. These early images suggest that the near-IR offers significant advantages over conventional visual, tactile and radiographic caries detection methods.

  18. Imaging of occlusal dental caries (decay) with near-IR light at 1310-nm.

    PubMed

    Bühler, Christopher; Ngaotheppitak, Patara; Fried, Daniel

    2005-01-24

    Dental enamel manifests high transparency in the near-IR. Previous work demonstrated that near-IR light at 1310-nm is ideally suited for the transillumination of interproximal dental caries (dental decay in between teeth) [1]. However, most new dental decay occurs in the pits and fissures of the occlusal (biting) surfaces of posterior teeth. These caries lesions cannot be detected by x-rays during the early stages of decay due to the overlapping topography of the crown of the tooth. In this study, a near- IR imaging system operating at 1310-nm was used to acquire occlusal images by launching the near-IR light into the buccal surface of the tooth just above the gingival margin (gum-line). The near-IR light diffuses through the highly scattering dentin providing uniform back illumination of the enamel of the crowns allowing imaging of the occlusal surfaces. The near-IR images show high contrast between sound and demineralized areas. Demineralization (decay) can be easily differentiated from stains, pigmentation, and hypomineralization (fluorosis). Moreover, the high transparency of the enamel enables imaging at greater depth for the detection of subsurface decay hidden under the enamel. These early images suggest that the near-IR offers significant advantages over conventional visual, tactile and radiographic caries detection methods.

  19. Novel calcium phosphate nanocomposite with caries-inhibition in a human in situ model

    PubMed Central

    Melo, Mary Anne S.; Weir, Michael D.; Rodrigues, Lidiany K.A.; Xu, Hockin H.K.

    2013-01-01

    Objectives Secondary caries at the restoration margins remains the main reason for failure. Although calcium phosphate (CaP) composites are promising for caries inhibition, there has been no report of CaP composite to inhibit caries in situ. The objectives of this study were to investigate the caries-inhibition effect of nanocomposite containing nanoparticles of amorphous calcium phosphate (NACP) in a human in situ model for the first time, and to determine colony-forming units (CFU) and Ca and P ion concentrations of biofilms on the composite restorations. Methods NACP with a mean particle size of 116 nm were synthesized via a spray-drying technique. Two composites were fabricated: NACP nanocomposite, and control composite filled with glass particles. Twenty-five volunteers wore palatal devices containing bovine enamel slabs with cavities restored with NACP or control composite. After 14 days, the adherent biofilms were collected for analyses. Transverse microradiography determined the enamel mineral profiles at the margins, and the enamel mineral loss ! Z was measured. Results NACP nanocomposite released Ca and P ions and the release significantly increased at cariogenic low pH (p < 0.05). Biofilms on NACP nanocomposite contained higher Ca (p = 0.007) and P ions (p = 0.005) than those of control (n = 25). There was no significant difference in biofilm CFU between the two composites (p > 0.1). Microradiographs showed typical subsurface lesions in enamel next to control composite, but much less lesion around NACP nanocomposite. Enamel mineral loss ! Z (mean ± sd; n = 25) around NACP nanocomposite was 13.8 ± 9.3 μm, much less than 33.5 ± 19.0 μm of the control (p = 0.001). Significance Novel NACP nanocomposite substantially reduced caries formation in a human in situ model for the first time. Enamel mineral loss at the margins around NACP nanocomposite was less than half of the mineral loss around control composite. Therefore, the Ca and P ion-releasing NACP

  20. Surface variations affecting human dental enamel studied using nanomechanical and chemical analysis

    NASA Astrophysics Data System (ADS)

    Dickinson, Michelle Emma

    The enamel surface is the interface between the tooth and its ever changing oral environment. Cavity (caries) formation and extrinsic tooth staining are due, respectively, to degradation of the enamel structure under low pH conditions and interactions between salivary pellicle and dietary elements. Both of these occur at the enamel surface and are caused by the local environment changing the chemistry of the surface. The results can be detrimental to the enamel's mechanical integrity and aesthetics. Incipient carious lesions are the precursor to caries and form due to demineralisation of enamel. These carious lesions are a reversible structure where ions (e.g. Ca2+, F -) can diffuse in (remineralisation) to preserve the tooth's structural integrity. This investigation used controlled in vitro demineralisation and remineralisation to study artificial carious lesion formation and repair. The carious lesions were cross-sectioned and characterised using nanoindentation, electron probe micro-analysis and time of flight secondary ion mass spectrometry. Mechanical and chemical maps showed the carious lesion had a significantly reduced hardness and elastic modulus, and the calcium and phosphate content was lower than in sound enamel. Fluoride based remineralisation treatments gave a new phase (possibly fluorohydroxyapatite) within the lesion with mechanical properties higher than sound enamel. The acquired salivary pellicle is a protein-rich film formed by the physisorption of organic molecules in saliva onto the enamel surface. Its functions include lubrication during mastication and chemical protection. However, pellicle proteins react with dietary elements such as polyphenols (tannins in tea) causing a brown stain. This study has used in vitro dynamic nanoindentation and atomic force microscopy to examine normal and stained pellicles formed in vivo. The effects of polyphenols on the pellicle's mechanical properties and morphology have been studied. It was found that the

  1. Fluoride use in caries prevention in the primary care setting.

    PubMed

    Clark, Melinda B; Slayton, Rebecca L

    2014-09-01

    Dental caries remains the most common chronic disease of childhood in the United States. Caries is a largely preventable condition, and fluoride has proven effectiveness in the prevention of caries. The goals of this clinical report are to clarify the use of available fluoride modalities for caries prevention in the primary care setting and to assist pediatricians in using fluoride to achieve maximum protection against dental caries while minimizing the likelihood of enamel fluorosis.

  2. EFFECT OF DIFFERENT PROPHYLAXIS METHODS ON SOUND AND DEMINERALIZED ENAMEL

    PubMed Central

    Honório, Heitor Marques; Rios, Daniela; Abdo, Ruy César Camargo; Machado, Maria Aparecida de Andrade Moreira

    2006-01-01

    Considering the importance of professional plaque control for caries prevention, this study comprised an in vitro evaluation of wear by two prophylaxis methods (sodium bicarbonate jet – Profident and pumice and brush) on sound bovine enamel and with artificial carious lesions. Sixty enamel fragments were employed (4x4mm), which were divided into 4 groups: GI – 15 sound blocks treated with pumice and brush; GII – 15 sound blocks treated with Profident; GIII – 15 demineralized blocks treated with pumice and brush, and GIV – 15 demineralized blocks treated with Profident. In the fragments of Groups III and IV, artificial carious lesions were simulated by immersion in 0.05M acetic acid solution 50% saturated with bovine enamel powder at 37oC for 16h. The specimens were submitted to the prophylactic treatments for 10 seconds. Wear analysis was performed by profilometer and revealed the following results: 0.91μm – GI; 0.42μm – GII; 1.6μm – GIII, and 0.94μm – GIV. The two-way ANOVA and Tukey's test (p<0.05) revealed significant difference between all groups. Scanning electron microscopy images were employed to illustrate the wear pattern, with observation of larger alteration on the demineralized enamel surface (GIII; GIV), round-shaped wear on GI and GIII and blasted aspect on GII and GIV. The study indicated that the demineralized enamel presented more wear than the sound enamel, and the brush led to larger wear when compared to Profident. PMID:19089042

  3. Occurrence and severity of enamel decalcification adjacent to bracket bases and sub-bracket lesions during orthodontic treatment with two different lingual appliances

    PubMed Central

    Klang, Elisabeth; Helms, Hans-Joachim; Wiechmann, Dirk

    2016-01-01

    Summary Background: Using lingual enamel surfaces for bracket placement not only has esthetic advantages, but may also be suitable in terms of reducing frequencies of enamel decalcifications. Objective: To test the null-hypothesis that there is no significant difference in enamel decalcification or cavitation incidence adjacent to and beneath bracket bases between two lingual multi-bracket (MB) appliances that are different in terms of design, material composition, and manufacturing technology (group A: WIN, DW-LingualSystems; group B: Incognito, 3M-Unitek), taking into account patient- and treatment-related variables on white spot lesion (WSL) formation. Methods: Standardized, digital, top-view photographs of 630 consecutive subjects (16214 teeth; n Incognito = 237/6076 teeth; n WIN = 393/10138 teeth; mean age: 17.47±7.8; m/f 43.2/56.8%) with completed lingual MB treatment of the upper and lower permanent teeth 1–7 were screened for decalcification or cavitation adjacent to and beneath the bracket bases before and after treatment, scored from 0 to 7. Non-parametric ANOVA was used for main effects ‘appliance type’, ‘gender’, ‘treatment complexity’, ‘grouped age’ (≤16/>16 years), and ‘treatment duration’ as covariable, at an α-level of 5%. Results: About 2.57% [5.94%] of all teeth in group A [B] developed decalcifications. Subject-related incidence was 9.59% [16.17%] for upper incisors in group A [B], and 12.98% [25.74%] for all teeth 16–46. There were significant effects by gender, age, and treatment duration. Conclusion: The null-hypothesis was rejected: sub-bracket lesions were significantly less frequent in group A, while frequencies of WSL adjacent to brackets were not significantly affected by appliance type. In view of the overall low incidences of lingual post-orthodontic white-spot lesions, the use of lingual appliances is advocated as a valid strategy for a reduction of enamel decalcifications during orthodontic treatment. PMID

  4. Resin infiltrant for non-cavitated caries lesions: evaluation of color stability

    PubMed Central

    Ceci, Matteo; Rattalino, Davide; Viola, Matteo; Beltrami, Riccardo; Chiesa, Marco; Colombo, Marco

    2017-01-01

    Background The objective of this in vitro study was to evaluate the over time color stability of one resin infiltrant (Icon) upon exposure to staining solutions (coffee and wine) compared with one nano-hybrid sealant (Grandio Seal), one transparent fissure sealant with fluoride (Control Seal) and one nanofilled composite (Filtek Supreme XTE). Material and Methods All materials were polymerized according to manufacturers’ instructions into silicon rings (height 1 mm; internal diameter 6 mm; external diameter 8 mm) to obtain specimens identical in size. The specimens were immersed in staining solutions at room temperature over a 28-day test period. The control samples have not been subjected to the staining process. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. Shapiro Wilk test and Kruskal Wallis ANOVA were applied to assess significant differences among different materials. Means were compared with Scheffe’s multiple-comparison test at the 0.05 level of significance. Results In the case of all materials, immersion in solutions resulted in clinically perceivable color changes after 1 week (∆E < 3.3). Lowest CIE L* variation was registered for Control Seal and Grandio Seal both after 1 week and after 1 month, while Icon showed significantly higher variation (P < 0.05). Color coordinate CIE a* varied significantly more for Icon samples (P > 0.05). Color coordinate CIE b* varied similarly for all materials tested (P > 0.05). Conclusions Immersion in coffee or red wine resulted in clinically perceivable color changes for all materials tested. Icon showed the highest color variations both after 1 week and 1 month. Icon can fix the initial esthetic problem associated with white spot lesions, but the resin may become more discolored than other materials over time. Key words:CIE Lab, color stability, resin infiltrant. PMID:28210441

  5. Drugs that promote dental caries.

    PubMed

    2015-02-01

    Dental caries result from erosion of tooth enamel or cementum by acidic substances produced by bacteria found in dental plaque. Caries can lead to pulp necrosis and tooth loss. Risk factors include certain dietary habits, poor oral hygiene, and dry mouth. Diabetes and Sjogren's syndrome can also promote dental caries. Psychotropic substances such as cocaine, methamphetamine, heroin and cannabis can promote dental caries. Many medicinal drugs facilitate the formation of dental caries, through various mechanisms; they include formulations with a high sugar content; drugs that cause dry mouth (especially antimuscarinics); drugs that lower the buccal pH (inhaled powders, etc.); and drugs that cause demineralisation (tetracyclines, etc.). In practice, patients (and parents) should be informed that some drugs can increase the risk of dental caries. They should be encouraged to adapt and reinforce dental hygiene, and advised to visit a dentist regularly.

  6. Diagnosis and Management of Hidden Caries in a Primary Molar Tooth

    PubMed Central

    Gera, Arwa

    2017-01-01

    Hidden caries is a dentinal lesion beneath the dentinoenamel junction, visible on radiographs. A single report described this lesion in primary dentition. This case report describes a case of hidden caries in a mandibular second primary molar, misdiagnosed as malignant swelling. A 3-year-old white girl was referred to the Department of Pediatric Dentistry with a chief complaint of pain and extraoral swelling on the right side of the mandible for the last 3 months. She was earlier referred to the surgical department for biopsy of the lesion. Radiographic and computed tomography scan examination showed a periapical lesion with buccal plate resorption and radiolucency beneath the enamel on the mesial part of tooth 85. The tooth was extracted, and follow-up of 2 years showed normal development of tooth 45. The main problem is early detection and treatment, since the outer surface of enamel may appear intact on tactile examination. How to cite this article Gera A, Zilberman U. Diagnosis and Management of Hidden Caries in a Primary Molar Tooth. Int J Clin Pediatr Dent 2017;10(1):99-102. PMID:28377664

  7. Selective removal of dental caries with a diode-pumped Er:YAG laser

    NASA Astrophysics Data System (ADS)

    Yan, Ruth; Chan, Kenneth H.; Tom, Henry; Simon, Jacob C.; Darling, Cynthia L.; Fried, Daniel

    2015-02-01

    Selective removal of caries lesions with high precision is best accomplished using lasers operating at high pulse repetition rates utilizing small spot sizes. Conventional flash-lamp pumped Er:YAG lasers are poorly suited for this purpose, but new diode-pumped Er:YAG lasers have become available operating at high pulse repetition rates. The purpose of this study was to measure the ablation rate and selectivity of sound and demineralized enamel and dentin for a 30 W diode-pumped Er:YAG laser operating with a pulse duration of 20-30-μs and evaluate it's potential for the selective removal of natural occlusal lesions on extracted teeth. Microradiography was used to determine the mineral content of the demineralized enamel and dentin of 300-μm thick sections with natural caries lesions prior to laser ablation. The ablation rate was calculated for varying mineral content. In addition, near-IR reflectance measurements at 1500-1700- nm were used to guide the laser for the selective ablation of natural occlusal caries lesions on extracted teeth.

  8. Mineralisation of developmentally hypomineralised human enamel in vitro.

    PubMed

    Crombie, F A; Cochrane, N J; Manton, D J; Palamara, J E A; Reynolds, E C

    2013-01-01

    Molar-incisor hypomineralisation (MIH) is a problematic and costly condition. Caries remineralising agents are often recommended for MIH management despite the lack of evidence that these lesions have the capacity for increasing their mineral content. Following surface layer removal ± NaOCl pre-treatment and 14-day exposure to a CPP-ACFP solution at pH 5.5, MIH lesions were analysed using transverse microradiography and polarised light microscopy. Lesions were highly variable but treatment with the remineralising solution increased mineral content (1,828 ± 461 vol% min · µm, %R = 17.7 ± 5.7) and porosity decreased demonstrating the proof of concept that the mineral content of developmentally hypomineralised enamel can be improved after eruption.

  9. Preparation of fluoride substituted apatite cements as the building blocks for tooth enamel restoration

    NASA Astrophysics Data System (ADS)

    Wei, Jie; Wang, Jiecheng; Liu, Xiaochen; Ma, Jian; Liu, Changsheng; Fang, Jing; Wei, Shicheng

    2011-06-01

    Fluoride substituted apatite cement (fs-AC) was synthesized by using the cement powders of tetracalcium phosphate (TTCP) and sodium fluoride (NaF), and the cement powders were mixed with diluted phosphoric acid (H 3PO 4) as cement liquid to form fs-AC paste. The fs-AC paste could be directly filled into the carious cavities to repair damaged dental enamel. The results indicated that the fs-AC paste was changed into fluorapatite crystals with the atom molar ratio for calcium to phosphorus of 1.66 and the F ion amount of 3 wt% after self-hardening for 2 days. The solubility of fs-AC in Tris-HCl solution (pH 6) was slightly lower than hydroxyapatite cement (HAC) that was similar to the apatite in enamel, indicating the fs-AC was much insensitive to the weakly acidic solution than the apatite in enamel. The fs-AC was tightly combined with the enamel surface because of the chemical reaction between the fs-AC and the apatite in enamel after the caries cavities was filled with fs-AC. The extracts of fs-AC caused no cytotoxicity on L929 cells, which satisfied the relevant criterion on dental biomaterials, revealing good cytocompatibility. The fs-AC had potential prospect for the reconstitution of carious lesion of dental enamel.

  10. [The study on chemical composition and crystalline structure of hypoplastic primary dental enamel].

    PubMed

    Zheng, S; Deng, H; Gao, X

    1997-11-01

    The present study, firstly, analyzed chemical composition of hypoplastic primary teeth by electron probe analyzer and compared the hypoplastic part with the normal part in the same tooth; secondly, by X-ray diffraction analyzer, studied the hypoplastic dental enamel and the normal dental enamel, and compared the crystalline structure between different dental enamel and with that of the hydroxyapatite. The aim was to find out any change of crystalline structure. Two exfoliated hypoplastic deciduous anterior teeth were used for the electron probe study. The normal part of each tooth served as control. Determinations of weight percentage (wt%) were made for P, Al, Mg, Ca, Mn, Fe, Zn, Sr, Na, K and F. Four exfoliated hypoplastic deciduous anterior teeth and eight exfoliated normal deciduous anterior teeth were used for the X-ray diffraction study. We found by X-ray diffraction that the length of the alpha-axis of enamel crystallite and the distance of lattice plane (corresponding 300) were increased in defective enamel and could be associated with the increased content of magnesium detected by electron probe. Thus, the present study demonstrated that there were both quantity and quality changes in the enamel hypoplasia lesion, which may increase the susceptibility of the defective teeth to caries.

  11. Optical diagnosis and characterization of dental caries with polarization-resolved hyperspectral stimulated Raman scattering microscopy

    PubMed Central

    Wang, Zi; Zheng, Wei; Hsu, Stephen Chin-Ying; Huang, Zhiwei

    2016-01-01

    We report the utility of a rapid polarization-resolved hyperspectral stimulated Raman scattering (SRS) imaging technique developed for optical diagnosis and characterization of dental caries in the tooth. Hyperspectral SRS images (512 × 512 pixels) of the tooth covering both the fingerprint (800-1800 cm−1) and high-wavenumber (2800-3600 cm−1) regions can be acquired within 15 minutes, which is at least 103 faster in imaging speed than confocal Raman mapping. Hyperspectral SRS imaging uncovers the biochemical distributions and variations across the carious enamel in the tooth. SRS imaging shows that compared to the sound enamel, the mineral content in the body of lesion decreases by 55%; while increasing up to 110% in the surface zone, indicating the formation of a hyper-mineralized layer due to the remineralization process. Further polarized SRS imaging shows that the depolarization ratios of hydroxyapatite crystals (ν1-PO43- of SRS at 959 cm−1) of the tooth in the sound enamel, translucent zone, body of lesion and the surface zone are 0.035 ± 0.01, 0.052 ± 0.02, 0.314 ± 0.1, 0.038 ± 0.02, respectively, providing a new diagnostic criterion for discriminating carious lesions from sound enamel in the teeth. This work demonstrates for the first time that the polarization-resolved hyperspectral SRS imaging technique can be used for quantitatively determining tooth mineralization levels and discriminating carious lesions from sound enamel in a rapid fashion, proving its promising potential of early detection and diagnosis of dental caries without labeling. PMID:27446654

  12. Laser-matrix-fluoride effects on enamel demineralization.

    PubMed

    Hsu, C Y; Jordan, T H; Dederich, D N; Wefel, J S

    2001-09-01

    Laser and fluoride have been shown to inhibit enamel demineralization. However, the role of organic matrix and their interactions remains unclear. This study investigated the interaction among CO2 laser irradiation, fluoride, and the organic matrix on the demineralization of human enamel. Twenty-four molars were selected and cut into halves. One half of each tooth was depleted of its lipid and protein. The other half served as a matched control. Each tooth half had two window areas, treated with a 2.0% NaF gel. All left windows then received a laser treatment. Next, the tooth halves were subjected to a four-day pH-cycling procedure that created caries-like lesions. Tooth sections were cut from the windows, and microradiographs were used for quantification of the demineralization. The combined fluoride-laser treatment led to 98.3% and 95.1% reductions in mineral loss for enamel with and without organic matrix, respectively, when compared with sound enamel.

  13. Effectiveness of plant-derived proanthocyanidins on demineralization on enamel and dentin under artificial cariogenic challenge

    PubMed Central

    da SILVA, Ana Paula Pereira; GONÇALVES, Rafael Simões; BORGES, Ana Flávia Sanches; BEDRAN-RUSSO, Ana Karina; SHINOHARA, Mirela Sanae

    2015-01-01

    Dental caries is considered a disease of high prevalence and a constant problem in public health. Proanthocyanidins (PAs) are substances that have been the target of recent studies aiming to control or treat caries. Objective The aim of this in vitro study was to evaluate the efficacy of a treatment with grape seed extract, under cariogenic challenge, to minimize or even prevent the onset of caries in the enamel and dentin. Material and Methods Blocks of enamel and dentin (6.0x6.0 mm) were obtained from bovine central incisors, polished, and selected by analysis of surface microhardness (SH). The blocks were randomly divided into 3 groups (n=15), according to the following treatments: GC (control), GSE (grape seed extract), GF (fluoride – 1,000 ppm). The blocks were subjected to 6 daily pH cycles for 8 days. Within the daily cycling, the specimens were stored in buffered solution. The blocks were then analyzed for perpendicular and surface hardness and polarized light microscopy. Results The means were subjected to statistical analysis using the ANOVA and Fisher’s PLSD tests (p<0.05). For enamel SH, GF showed the highest hardness values. In the dentin, GF was also the one that showed higher hardness values, followed by GSE. Regarding the cross-sectional hardness values, all groups behaved similarly in both the enamel and dentin. The samples that were treated with GSE and fluoride (GF) showed statistically higher values than the control. Conclusion Based on the data obtained in this in vitro study, it is suggested that grape seed extract inhibits demineralization of artificial carious lesions in both the enamel and dentin, but in a different scale in each structure and in a smaller scale when compared to fluoride. PMID:26221925

  14. Effects of carboxymethyl cellulose-based saliva substitutes with varying degrees of saturation with respect to calcium phosphates on artificial enamel lesions.

    PubMed

    Meyer-Lueckel, H; Cölfen, H; Verch, A; Tschoppe, P

    2010-01-01

    The aim of the present study was to evaluate the effects of experimental saliva substitutes based on carboxymethyl cellulose (CMC) differing in degrees of saturation with respect to calcium phosphates on the mineral loss of enamel in vitro. Demineralized bovine specimens (subsurface lesions) were exposed to one of six experimental CMC-based solutions with theoretical degrees of saturation with respect to octacalcium phosphate (S(OCP)) of S0, S0.5, S1, S2, S4, and S8 for 10 weeks. A previously studied saliva substitute (Glandosane) and two aqueous solutions (C0 and C1) served as controls. Mineral losses and lesion depths before and after storage were evaluated from microradiographs. Free and bound calcium as well as phosphate and fluoride concentrations were determined. According to these measurements, S(OCP) of S2, S4, and S8 was 0.3, 1.1, and 3.4, respectively. Storage in Glandosane and both negative controls resulted in significant demineralization (p < 0.05). Only S2 significantly remineralized the specimens (p < 0.05). All other solutions showed neutral effects. No significant differences in mineralization between S0 and C0 as well as between S1 and C1 could be observed (p > 0.05). It can be concluded that a CMC-based solution actually unsaturated with respect to octacalcium phosphate (S2) shows most pronounced remineralization capability under the conditions chosen. This might be explained by a more favorable balance between calcium bound to CMC in an adsorbed layer at the enamel-liquid interface and heterogeneous nucleation of calcium phosphates within a solution compared to solutions either supersaturated or having lower levels of saturation.

  15. Ex vivo imaging of early dental caries within the interproximal space

    NASA Astrophysics Data System (ADS)

    Choo-Smith, Lin-P'ing; Hewko, Mark D.; Dufour, Marc L.; Fulton, Crystal; Qiu, Pingli; Gauthier, Bruno; Padioleau, Christian; Bisaillon, Charles-Etienne; Dong, Cecilia; Cleghorn, Blaine M.; Lamouche, Guy; Sowa, Michael G.

    2009-02-01

    Optical coherence tomography (OCT) is emerging as a technology that can potentially be used for the detection and monitoring of early dental enamel caries since it can provide high-resolution depth imaging of early lesions. To date, most caries detection optical technologies are well suited for examining caries at facial, lingual, incisal and occlusal surfaces. The approximal surfaces between adjacent teeth are difficult to examine due to lack of visual access and limited space for these new caries detection tools. Using a catheter-style probe developed at the NRC-Industrial Materials Institute, the probe was inserted into the interproximal space to examine the approximal surfaces with OCT imaging at 1310 nm. The probe was rotated continuously and translated axially to generate depth images in a spiral fashion. The probe was used in a mock tooth arch model consisting of extracted human teeth mounted with dental rope wax in their anatomically correct positions. With this ex vivo model, the probe provided images of the approximal surfaces revealing morphological structural details, regions of calculus, and especially regions of early dental caries (white spot lesions). Results were compared with those obtained from OCT imaging of individual samples where the approximal surfaces of extracted teeth are accessible on a lab-bench. Issues regarding access, regions of interest, and factors to be considered in an in vivo setting will be discussed. Future studies are aimed at using the probe in vivo with patient volunteers.

  16. Secondary caries formation in vitro around glass ionomer-lined amalgam and composite restorations.

    PubMed

    Dionysopoulos, P; Kotsanos, N; Papadogianis, Y

    1996-08-01

    The aim of this in vitro secondary caries study was to examine the glass-ionomer liner's effect on wall-lesion inhibition when a conventional and a light-cured glass ionomer liner was placed under amalgam and composite resin restorations. Class V preparations in extracted upper premolars were used and ten restorations were used for each of the following groups: (i) two layers of copal varnish and amalgam; (ii) conventional glass-ionomer and amalgam; (iii) light-cured glass-ionomer and amalgam; (iv) bonding agent and light-cured composite resin; (v) conventional glass-ionomer, bonding agent and light-cured composite resin; (vi) light-cured glass-ionomer, extended 0.3 mm short of the enamel margin bonding agent and light-cured composite resin; and (vii) light-cured glass-ionomer, extended 1 mm short of the enamel margin, bonding agent and light-cured composite resin. The teeth were thermocycled and artificial caries were created using an acid-gel. The results of this study showed that artificial recurrent caries can be reduced significantly (P < 0.05) with a glass-ionomer liner under amalgam restorations. The results also showed that when the light-cured glass-ionomer liner was placed 0.3 mm from the cavosurface margin under composite resin restoration, the artificial recurrent caries reduced significantly (P < 0.05).

  17. Weaker Dental Enamel Explains Dental Decay

    PubMed Central

    Vieira, Alexandre R.; Gibson, Carolyn W.; Deeley, Kathleen; Xue, Hui; Li, Yong

    2015-01-01

    Dental caries continues to be the most prevalent bacteria-mediated non-contagious disease of humankind. Dental professionals assert the disease can be explained by poor oral hygiene and a diet rich in sugars but this does not account for caries free individuals exposed to the same risk factors. In order to test the hypothesis that amount of amelogenin during enamel development can influence caries susceptibility, we generated multiple strains of mice with varying levels of available amelogenin during dental development. Mechanical tests showed that dental enamel developed with less amelogenin is “weaker” while the dental enamel of animals over-expressing amelogenin appears to be more resistant to acid dissolution. PMID:25885796

  18. Transillumination and reflectance probes for in vivo near-IR imaging of dental caries

    NASA Astrophysics Data System (ADS)

    Simon, Jacob C.; Lucas, Seth A.; Staninec, Michal; Tom, Henry; Chan, Kenneth H.; Darling, Cynthia L.; Fried, Daniel

    2014-02-01

    Previous studies have demonstrated the utility of near infrared (NIR) imaging for caries detection employing transillumination and reflectance imaging geometries. Three intra-oral NIR imaging probes were fabricated for the acquisition of in vivo, real time videos using a high definition InGaAs SWIR camera and near-IR broadband light sources. Two transillumination probes provide occlusal and interproximal images using 1300-nm light where water absorption is low and enamel manifests the highest transparency. A third reflectance probe utilizes cross polarization and operates at >1500-nm, where water absorption is higher which reduces the reflectivity of sound tissues, significantly increasing lesion contrast. These probes are being used in an ongoing clinical study to assess the diagnostic performance of NIR imaging for the detection of caries lesions in teeth scheduled for extraction for orthodontic reasons.

  19. Trimodal detection of early childhood caries using laser light scanning and fluorescence spectroscopy: clinical prototype

    PubMed Central

    Kim, Amy S.; Ridge, Jeremy S.; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    2013-01-01

    Abstract. There is currently a need for a safe and effective way to detect and diagnose early stages of childhood caries. A multimodal optical clinical prototype for diagnosing caries demineralization in vivo has been developed. The device can be used to quickly image and screen for any signs of demineralized enamel by obtaining high-resolution and high-contrast surface images using a 405-nm laser as the illumination source, as well as obtaining autofluorescence and bacterial fluorescence images. When a suspicious region of demineralization is located, the device also performs dual laser fluorescence spectroscopy using 405- and 532-nm laser excitation. An autofluorescence ratio of the two excitation lasers is computed and used to quantitatively diagnose enamel health. The device was tested on five patients in vivo as well as on 28 extracted teeth with clinically diagnosed carious lesions. The device was able to provide detailed images that highlighted the lesions identified by the clinicians. The autofluorescence spectroscopic ratios obtained from the extracted teeth successfully quantitatively discriminated between sound and demineralized enamel. PMID:23986369

  20. Effects of low-energy CO2 laser irradiation and the organic matrix on inhibition of enamel demineralization.

    PubMed

    Hsu, C Y; Jordan, T H; Dederich, D N; Wefel, J S

    2000-09-01

    In the past two decades, accumulated evidence has clearly demonstrated the inhibitory effects of laser irradiation on enamel demineralization, but the exact mechanisms of these effects remain unclear. The purpose of this study was to investigate the effects of low-energy CO2 laser irradiation on demineralization of both normal human enamel and human enamel with its organic matrix removed. Twenty-four human molars were collected, cleaned, and cut into two halves. One half of each tooth was randomly selected and its lipid and protein content extracted. The other half of each tooth was used as the matched control. Each tooth half had two window areas. All the left windows were treated with a low-energy laser irradiation, whereas the right windows served as the non-laser controls. After caries-like lesion formation in a pH-cycling environment, microradiographs of tooth sections were taken for quantification of demineralization. The mean mineral losses (with standard deviation) of the enamel control, the lased enamel, the non-organic enamel control, and the lased non-organic enamel subgroups were 3955 (1191), 52(49), 4565(1311), and 1191 (940), respectively. A factorial ANOVA showed significant effects of laser irradiation (p = 0.0001), organic matrix (p = 0.0125), and the laser-organic matrix interaction (p = 0.0377). The laser irradiation resulted in a greater than 98% reduction in mineral loss, but the laser effect dropped to about 70% when the organic matrix in the enamel was removed. The results suggest that clinically applicable CO2 laser irradiation may cause an almost complete inhibition of enamel demineralization.

  1. A simple dental caries detection system using full spectrum of laser-induced fluorescence

    NASA Astrophysics Data System (ADS)

    Rocha-Cabral, Renata Maciel; Mendes, Fausto Medeiros; Maldonado, Edison Puig; Zezell, Denise Maria

    2015-06-01

    Objectives: to develop an apparatus for the detection of early caries lesions in enamel using the full extent of the tooth fluorescence spectrum, through the integration of a laser diode, fiber optics, filters and one portable spectrometer connected to a computer, all commercially available; to evaluate the developed device in clinical and laboratory tests, and compare its performance with commercial equipment. Methods: clinical examinations were performed in patients with indication for exodontics of premolars. After examinations, the patients underwent surgery and the teeth were stored individually. The optical measurements were repeated approximately two months after extraction, on the same sites previously examined, then histological analysis was carried out. Results: the spectral detector has presented high specificity and moderate sensitivity when applied to differentiate between healthy and damaged tissues, with no significant differences from the performance of the commercial equipment. The developed device is able to detect initial damages in enamel, with depth of approximately 300 μm. Conclusions: we successfully demonstrated the development of a simple and portable system based in laser-induced fluorescence for caries detection, assembled from common commercial parts. As the spectral detector acquires a complete recording of the spectrum from each tissue, it is possible to use it for monitoring developments of caries lesions.

  2. Comparing natural and artificial carious lesions in human crowns by means of conventional hard x-ray micro-tomography and two-dimensional x-ray scattering with synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Botta, Lea Maria; White, Shane N.; Deyhle, Hans; Dziadowiec, Iwona; Schulz, Georg; Thalmann, Peter; Müller, Bert

    2016-10-01

    Dental caries, one of the most prevalent infectious bacterial diseases in the world, is caused by specific types of acid-producing bacteria. Caries is a disease continuum resulting from the earliest loss of ions from apatite crystals through gross cavitation. Enamel dissolution starts when the pH-value drops below 5.5. Neutralizing the pH-value in the oral cavity opposes the process of demineralization, and so caries lesions occur in a dynamic cyclic de-mineralizing/remineralizing environment. Unfortunately, biomimetic regeneration of cavitated enamel is not yet possible, although remineralization of small carious lesions occurs under optimal conditions. Therefore, the development of methods that can regenerate carious lesions, and subsequently recover and retain teeth, is highly desirable. For the present proceedings we analyzed one naturally occurring sub-surface and one artificially produced lesion. For the characterization of artificial and natural lesions micro computed tomography is the method of choice when looking to determine three-dimensional mineral distribution and to quantify the degree of mineralization. In this pilot study we elucidate that the de-mineralized enamel in natural and artificially induced lesions shows comparable X-ray attenuation behavior, thereby implying that the study protocol employed herein seems to be appropriate. Once we know that the lesions are comparable, a series of well-reproducible in vitro experiments on enamel regeneration could be performed. In order to quantify further lesion morphology, the anisotropy of the enamel's nanostructure can be characterized by using spatially resolved, small-angle X-ray scattering. We wanted to demonstrate that the artificially induced defect fittingly resembles the natural carious lesion.

  3. Fluorine uptake into the human enamel surface from fluoride-containing sealing materials during cariogenic pH cycling

    NASA Astrophysics Data System (ADS)

    Yasuhiro, Matsuda; Katsushi, Okuyama; Hiroko, Yamamoto; Hisanori, Komatsu; Masashi, Koka; Takahiro, Sato; Naoki, Hashimoto; Saiko, Oki; Chiharu, Kawamoto; Hidehiko, Sano

    2015-04-01

    To prevent the formation of caries and reduce dentin hypersensitivity, sealing materials, either with or without fluoride, are generally applied on the tooth in clinical practice. Application of fluoride-free sealing materials results in the formation of an acid-resistant layer on the tooth surface. On the other hand, fluoride-containing sealing materials might not only form an acid-resistant layer but could possibly further provide fluoride to enhance remineralization and reduce demineralization. In this study, the demineralization prevention ability and fluorine uptake rate in human enamel of fluoride-containing sealing materials ["MS coats F" (MSF)] and fluoride-free sealing materials ("hybrid coats 2" [HI]) were evaluated using an automatic pH cycling system. Each material was applied to the original tooth surface, the cut surfaces were covered with sticky wax, and the automatic pH-cycling system simulated daily acid changes (pH 6.8-4.5) occurring in the oral cavity for 4 weeks. Caries progression was analyzed using transverse microradiography (TMR) taken pre and post the 4 weeks of pH cycling. The fluorine and calcium distributions in the carious lesion in each specimen were evaluated using the proton-induced gamma emission (PIGE) and proton-induced X-ray (PIXE) techniques, respectively. TMR analysis showed that both MSF and HI had a caries-preventing effect after 4 weeks of pH cycling. PIGE/PIXE analysis demonstrated that only MSF resulted in fluoride uptake in the enamel surface. Therefore, MSF can help to form an acid-resistant layer and provide fluoride to the enamel surface. The presence of fluoride on the enamel surface suggested that MSF could prevent demineralization, even if the acid-resistant layer was removed, in clinical settings. The data obtained using the PIGE and PIXE techniques are useful for understanding the benefits of the use of a fluoride-containing sealing material for preventing caries.

  4. Comparison of Blue Wavelengths and Scan Velocity Effects on the Detection of Enamel Surface Caries Using Steady-State Laser-Induced Autofluorescence Spectroscopy

    NASA Astrophysics Data System (ADS)

    Khosroshahi, M. E.; Khoi, N. Taghizadeh

    2014-05-01

    The results of sound and carious enamel fl uorescence emission study using (i) different blue wavelengths, (ii) different scan velocity, and (iii) spectral ratio are reported. The samples were irradiated using a tunable argon laser emitting at 459 and 488 nm and a 405 nm laser at two different scan velocities of 0.23 and 0.5 mm/s. The results showed a spectral band of 443-492 nm for 405 nm, 493-522 nm for 459 nm, and 526-625 nm for 488 nm lasers for sound teeth. It was found from the emission spectra that with increase in the excitation wavelength, the corresponding primary peaks of the carious samples showed Stokes shifts of 4, 6, and 2 nm, respectively. No signifi cant change was observed for the secondary peaks. Also, in all cases, the intensity of fl uorescence signals of sound teeth was higher than those of carious teeth. The highest shape factor of 1.82 and integrated intensity ratio of 1.20 were achieved at 405 nm, which provides relatively better tissue discrimination. Also, increasing the scan velocity reduced the signal amplitudes in both sound and carious samples.

  5. Dental students’ and lecturers’ perception of the degree of difficulty of caries detection associated learning topics in Brazil

    PubMed Central

    2015-01-01

    Purpose: It aimed to explore the degree of difficulty of caries-detection-associated-topics perceived by dental students and lecturers as pedagogical step in the development of learning objects for e-learning. Methods: A convenience sample comprising ninety-eight subjects from different academic levels (undergraduate/graduate students and pediatric dentistry lecturers) participated. Two spreadsheets (isolated/relative) were created considering key topics in the caries detection process. The isolated evaluation intended to explore each topic in an isolated way, while the relative intended to classify, comparatively, the participants’ perceived difficulty per topic. Afterwards, data were analyzed. All values on spreadsheets were combined obtaining the subject’s final perception. Associations between the subjects’ degree of the perceived difficulty and academic level were estimated. ANOVA was used to determine differences regarding the perception among evaluated topics in distinct groups. Results: Caries histopathology and detection of proximal carious lesions were the topics perceived as the most difficult in the process of caries detection by both students and lecturers. Differentiation between an extrinsic pigmentation and a brown-spot (caries lesion) as well as differential diagnosis between caries and enamel developmental defects or non-carious lesions were considered as more difficult by undergraduates in comparison to graduates/lecturers (regression-coefficient=14.54; Standard Error=3.34; P<0.001 and 8.40, 3.31, and 0.01 respectively). Conclusion: Topics as histopathology and detection of proximal caries lesions were identified as the most difficult despite the academic level. However, some topics are differently perceived according to the group. These results are useful for developing pedagogical material, based on the students real learning needs/expectations. PMID:26708573

  6. Prevention of enamel demineralization with a novel fluoride strip: enamel surface composition and depth profile

    PubMed Central

    Lee, Bor-Shiunn; Chou, Po-Hung; Chen, Shu-Yu; Liao, Hua-Yang; Chang, Che-Chen

    2015-01-01

    There is no topically applicable low concentration fluoride delivery device available for caries prevention. This study was aimed to assess the use of a low concentration (1450 ppm) fluoride strip as an effective fluoride delivery system against enamel demineralization. The enamel surface composition and calcium-deficient hydroxyapatite or toothpaste treatments were investigated using X-ray photoelectron spectroscopy. In vitro enamel demineralization was assayed using a pH cycling model and the dissolution of calcium ions from the treated specimens was quantified using ion chromatography. After 24-hr fluoride-strip treatment, the enamel was covered with a CaF2 layer which showed a granular morphology of 1 μm in size. Below the CaF2 layer was a region of mixed fluorapatite and CaF2. Fluoride infiltrated extensively in enamel to produce highly fluorinated fluorohydroxyapatite. In comparison, low-fluoride-level fluorinated fluorohydroxyapatite was formed on the enamel specimen exposed to toothpaste. The treatments with the fluoride strip as short as 1 hr significantly inhibited enamel demineralization. The fluoride strip was effective for topical fluoride delivery and inhibited in vitro demineralization of enamel by forming CaF2 and fluoride-containing apatites at the enamel surface. It exhibited the potential as an effective fluoride delivery device for general use in prevention of caries. PMID:26293361

  7. Prevention of enamel demineralization with a novel fluoride strip: enamel surface composition and depth profile.

    PubMed

    Lee, Bor-Shiunn; Chou, Po-Hung; Chen, Shu-Yu; Liao, Hua-Yang; Chang, Che-Chen

    2015-08-21

    There is no topically applicable low concentration fluoride delivery device available for caries prevention. This study was aimed to assess the use of a low concentration (1450 ppm) fluoride strip as an effective fluoride delivery system against enamel demineralization. The enamel surface composition and calcium-deficient hydroxyapatite or toothpaste treatments were investigated using X-ray photoelectron spectroscopy. In vitro enamel demineralization was assayed using a pH cycling model and the dissolution of calcium ions from the treated specimens was quantified using ion chromatography. After 24-hr fluoride-strip treatment, the enamel was covered with a CaF2 layer which showed a granular morphology of 1 μm in size. Below the CaF2 layer was a region of mixed fluorapatite and CaF2. Fluoride infiltrated extensively in enamel to produce highly fluorinated fluorohydroxyapatite. In comparison, low-fluoride-level fluorinated fluorohydroxyapatite was formed on the enamel specimen exposed to toothpaste. The treatments with the fluoride strip as short as 1 hr significantly inhibited enamel demineralization. The fluoride strip was effective for topical fluoride delivery and inhibited in vitro demineralization of enamel by forming CaF2 and fluoride-containing apatites at the enamel surface. It exhibited the potential as an effective fluoride delivery device for general use in prevention of caries.

  8. Influence of Cavity Preparation with Er,Cr:YSGG Laser and Restorative Materials on In Situ Secondary Caries Development

    PubMed Central

    Jorge, Ana Carolina Tedesco; Cassoni, Alessandra; de Freitas, Patrícia Moreira; Reis, André Figueiredo; Junior, Aldo Brugnera

    2015-01-01

    Abstract Objective: The aim of this study was to evaluate the influence of cavity preparation and restorative materials containing fluorides in the prevention of secondary caries lesion development in situ. Methods: A total of 120 blocks obtained from human teeth were divided into two groups and standardized cavities were prepared using diamond burs (DB) or Er,Cr:YSGG-laser [20 Hz, 4.0W, 55% water, 65% air (LA)]. They were divided into three subgroups according to the restorative material (n=20): glass-ionomer cement (GI), resin modified glass-ionomer (RM) or composite resin (CR). Blocks were fixed in palatal intra-oral appliances worn in situ by 20 human volunteers, who dropped 20% sucrose solution eight times daily. After 21 days, blocks were removed and restorations were cross-sectioned to evaluate microhardness [Knoop hardness number (KHN)] underneath enamel surface from 30 to 200 μm. Factors “cavity preparation,” “restorative materials,” and “depth” were evaluated by three way ANOVA, followed by Tukey test (p<0.05). Results: The results showed lower microhardness in cavities prepared with DB than in cavities prepared with LA. At 30 μm, there were no statistical significant differences with regard to “cavity preparation” or “restorative materials” factors. In depth evaluation, the enamel microhardness progressively increased as a function of depth for the GI groups. In the groups prepared with LA at 60 μm/90 μm, there were no significant differences between GI and RM materials, whose microhardnesses were significantly higher than that of CR. Conclusions: Cavity preparation using Er,Cr:YSGG laser increases caries resistance of enamel walls, and reduce caries lesion depth development regardless of fluoride presence in the restorative material. CR showed higher caries lesion development than GI, and RM showed intermediate results. PMID:25654424

  9. In vitro evaluation of remineralization efficacy of different calcium- and fluoride-based delivery systems on artificially demineralized enamel surface

    PubMed Central

    Gangrade, Aparajita; Gade, Vandana; Patil, Sanjay; Gade, Jaykumar; Chandhok, Deepika; Thakur, Deepa

    2016-01-01

    Background: Caries is the most common dental disease facing the world population. Caries can be prevented by remineralizing early enamel lesions. Aim: To evaluate remineralization efficacy of stannous fluoride (SnF2), casein phosphopeptide-amorphous calcium phosphate with fluoride (CPP-ACPF) and calcium sucrose phosphate (CaSP). Materials and Methods: Fifty enamel samples were taken; they were divided into five groups (n = 10). Demineralization was carried out with Groups A, B, C, and E. Remineralization was carried out with Groups A, B, and C for 7 days using SnF2, CPP-ACPF, and CaSP, respectively. In Group D, no surface treatment was carried out, to mark as positive control whereas Group E was kept as negative control with only surface demineralization of enamel. Enamel microhardness was tested using Vickers's microhardness tester after 7 day remineralization regime. Statistical Analysis: One-way analysis of variance and post hoc Tukey tests were performed. Results: The mean microhardness values in descending order: Positive control > SnF2> CaSP > CPP-ACPF > negative control. Conclusion: All remineralizing agents showed improved surface remineralization. However, complete remineralization did not occur within 7 days. SnF2 showed the highest potential for remineralization followed by CaSP and CPP-ACPF. PMID:27563180

  10. Estimation of lesion progress in artificial root caries by swept source optical coherence tomography in comparison to transverse microradiography

    NASA Astrophysics Data System (ADS)

    Natsume, Yuko; Nakashima, Syozi; Sadr, Alireza; Shimada, Yasushi; Tagami, Junji; Sumi, Yasunori

    2011-07-01

    This study aimed to investigate whether swept source optical coherence tomography (SS-OCT) could estimate the lesion depth and mineral loss quantitatively without the use of polarization sensitivity, and to examine a relationship between OCT data and transverse microradiography (TMR) lesion parameters. Twenty-four bovine root dentin specimens were allocated to three groups of 4-, 7-, and 14-day demineralization. Cross-sectional images of the specimens before and after the demineralization were captured by OCT at 1319 nm center wavelength. Following the demineralization, these specimens were cut into sections for TMR analysis. Correlations between the OCT data and TMR lesion parameters were examined. TMR images of the specimens showed cavitated lesions (lesion depth or LDTMR: 200 to 500 μm, ΔZ or mineral loss: 10,000 to 30,000 vol % μm). The OCT images showed ``boundaries,'' suggesting the lesion front. Integrated dB values before and after the demineralization and their difference (RD, RS, and ΔR, respectively) were calculated from the lesion surface to the corrected depth of boundary (LDOCT). A statistically significant correlation was found between LDOCT and LDTMR (p < 0.05, r = 0.68). Similarly, statistically significant correlations were found between ΔZ and RD or ΔR. The OCT showed a potential for quantitative estimation of lesion depth and mineral loss with cavitated dentin lesions in vitro.

  11. Restoration Materials and Secondary Caries Using an In Vitro Biofilm Model

    PubMed Central

    van de Sande, F.H.; Opdam, N.J.M.; Bronkhorst, E.M.; de Soet, J.J.; Cenci, M.S.; Huysmans, M.C.D.J.N.M.

    2015-01-01

    This in vitro study investigated whether restoration materials and adhesives influence secondary caries formation in gaps using a short-term in vitro biofilm model. Sixty enamel–dentin blocks were restored with 6 different restoration materials with or without adhesives (n = 10 per group) with a gap: 1) Clearfil AP-X composite, 2) Clearfil AP-X composite + SE Bond, 3) Clearfil AP-X composite + ProtectBond, 4) Filtek Silorane composite, 5) Filtek Silorane composite + Silorane System adhesive, or 6) Tytin amalgam. Specimens were subjected to an intermittent 1% sucrose biofilm model for 20 days to create artificial caries lesions. Lesion progression in the enamel–dentin next to the different materials was measured in lesion depth (LD) and mineral loss (ML) using transversal wavelength independent microradiography (T-WIM). A regression analysis was used to compare the LD and ML of the different restoration materials at 4 measurement locations: 1 location at the surface of the enamel, 1 location at the wall of the enamel, and 2 locations at the wall of the dentin. A statistically significant effect of AP-X composite with Protect Bond was found for LD and ML at the WallDentin1 location, leading to less advanced wall lesions. An additional finding was that gap size was also statistically significant at the 2 wall locations in dentin, leading to increasing lesion progression with wider gaps. In conclusion, adhesives can influence wall lesion development in gaps. Protect Bond showed significantly less caries progression compared to bare restoration materials or other adhesives in this short-term in vitro biofilm model. PMID:25297114

  12. The association between social deprivation and the prevalence and severity of dental caries and fluorosis in populations with and without water fluoridation

    PubMed Central

    2012-01-01

    Background To determine the association between social deprivation and the prevalence of caries (including caries lesions restricted to enamel) and enamel fluorosis in areas that are served by either fluoridated or non-fluoridated drinking water using clinical scoring, remote blinded, photographic scoring for caries and fluorosis. The study also aimed to explore the use of remote, blinded methodologies to minimize the effect of examiner bias. Methods Subjects were male and female lifetime residents aged 11–13 years. Clinical assessments of caries and fluorosis were performed on permanent teeth using ICDAS and blind scoring of standardized photographs of maxillary central incisors using TF Index (with cases for fluorosis defined as TF > 0). Results Data from 1783 subjects were available (910 Newcastle, 873 Manchester). Levels of material deprivation (Index of Multiple Deprivation) were comparable for both populations (Newcastle mean 35.22, range 2.77-78.85; Manchester mean 37.04, range 1.84-84.02). Subjects in the fluoridated population had significantly less caries experience than the non-fluoridated population when assessed by clinical scores or photographic scores across all quintiles of deprivation for white spot lesions: Newcastle mean DMFT 2.94 (clinical); 2.51 (photo), Manchester mean DMFT 4.48 (clinical); 3.44 (photo) and caries into dentine (Newcastle Mean DMFT 0.65 (clinical); 0.58 (photo), Manchester mean DMFT 1.07 (clinical); 0.98 (photo). The only exception being for the least deprived quintile for caries into dentine where there were no significant differences between the cities: Newcastle mean DMFT 0.38 (clinical); 0.36 (photo), Manchester mean DMFT 0.45 (clinical); 0.39 (photo). The odds ratio for white spot caries experience (or worse) in Manchester was 1.9 relative to Newcastle. The odds ratio for caries into dentine in Manchester was 1.8 relative to Newcastle. The odds ratio for developing fluorosis in Newcastle was 3.3 relative to

  13. Dentin Caries Zones

    PubMed Central

    Pugach, M.K.; Strother, J.; Darling, C.L.; Fried, D.; Gansky, S.A.; Marshall, S.J.; Marshall, G.W.

    2009-01-01

    Caries Detector staining reveals 4 zones in dentin containing caries lesions, but characteristics of each zone are not well-defined. We therefore investigated the physical and microstructural properties of carious dentin in the 4 different zones to determine important differences revealed by Caries Detector staining. Six arrested dentin caries lesions and 2 normal controls were Caries-Detector-stained, each zone (pink, light pink, transparent, apparently normal) being analyzed by atomic force microscopy (AFM) imaging for microstructure, by AFM nano-indentation for mechanical properties, and by transverse digital microradiography (TMR) for mineral content. Microstructure changes, and nanomechanical properties and mineral content significantly decreased across zones. Hydrated elastic modulus and mineral content from normal dentin to pink Caries-Detector-stained dentin ranged from 19.5 [10.6-25.3] GPa to 1.6 [0.0-5.0] GPa and from 42.9 [39.8-44.6] vol% to 12.4 [9.1-14.2] vol%, respectively. Even the most demineralized pink zone contained considerable residual mineral. PMID:19131321

  14. Maize dependence or market integration? Caries prevalence among indigenous Maya communities with maize-based versus globalized economies.

    PubMed

    Vega Lizama, Elma Maria; Cucina, Andrea

    2014-02-01

    The relationship between diet and oral health is widely known, yet data on dental caries prevalence is lacking for many indigenous groups with traditional or rapidly modernizing diets. This research documents caries prevalence in two Maya communities from northern Yucatán (Mexico) with significantly different levels of market integration, subsistence, and diet: Yalsihón, with a traditional, maize-based subsistence economy, and Dzilam, with access to globalized food markets. Each sample was subdivided by sex into 15-19, 20-24, and 25-30 years-of-age classes. Caries prevalence was considered separately both when the lesion affected the enamel superficially (grade 1+) and when it reached the dentin (grade 2+). In both villages, females of all age classes manifest more caries than males. Results show higher prevalence of caries at Dzilam than at Yalsihón, except for grade 1+ caries among 15-19-year-old males and grade 2+ caries among 15-19-year-old females. Though differences are not significant, earlier pregnancies among 15-19-year-old females at Yalsihón could be a causative factor. A survey indicated a more balanced diet at Yalsihón despite a heavier intake of maize than at Dzilam. Striking differences were documented in the ingestion of soda and globalized foods; sodas were virtually absent at Yalsihón, while at Dzilam they were ingested daily in great quantities. The decline in oral health at Dzilam is inferred to result from consumption of industrially processed foods and drinks, while a traditional diet leads to less caries despite daily heavy consumption of maize, which must be considered when interpreting caries rates in archaeological samples.

  15. Formation of caries-like lesions in vitro on the root surfaces of human teeth in solutions simulating plaque fluid.

    PubMed

    Shellis, R P

    2010-01-01

    Lesion formation on root surfaces of human posterior teeth was studied in acetate/lactate buffers with a background electrolyte composition based on plaque fluid analyses. Lesion depth after 28 days at 37 degrees C was measured in relation to: the presence or absence of cementum; the concentration of undissociated buffer; the presence or absence of magnesium ions at plaque fluid concentration. Each factor was evaluated at several values of -log(ion activity product for hydroxyapatite): pI(HA). Solutions were formulated to minimize variation in pH, which varied by < or =0.03 for a given comparison (individual pI(HA)) and by 0.42-0.82 over the range of pI(HA) within experiments. Lesions on surfaces from which cementum had been ground were significantly deeper than on intact surfaces, but this is considered to be due to subsurface mechanical damage and not to a solubility difference. Neither the concentration of undissociated buffer nor the presence of magnesium ions significantly affected lesion depth. Lesion depth was strongly influenced by the correlated variations in pI(HA) and pH. At pI(HA) 54 and 55, only extremely shallow lesions formed. From pI(HA) 56, lesion depth increased with increasing pI(HA). The results confirm that the solubility of the mineral of root tissues is higher than that of hydroxyapatite, but indicate that it is probably lower than suggested by Hoppenbrouwers et al. [Arch Oral Biol 1987;32:319-322]. For calcium concentrations of 3-12 mM, the critical pH for root tissue mineral was calculated as 5.22-5.66 assuming solubility equivalent to pI(HA) 54 and 5.08-5.51 assuming pI(HA) 55.

  16. Enamel fusion using a carbon dioxide laser: A technique for sealing pits and fissures

    SciTech Connect

    Walsh, L.J.; Perham, S.J. )

    1991-05-01

    The well-established enhanced resistance of lased enamel to demineralization is the basis for clinical application of the carbon dioxide laser to caries prevention. This in vitro study examined the effect of focused infrared laser radiation on sound enamel and early pit and fissure caries. Low power levels (2-5 W) induced localized melting and resolidification of enamel with little surface destruction. For sound fissures, fusion of enamel from the lateral walls of the fissure eliminated the fissure space, providing a sealant effect; while in carious fissures, carious enamel was vaporized and adjacent sound enamel fused to partially eliminate the defect. The technique for enamel fusion using CO2 lasers has potential application for sealing pits and fissures and producing physicochemical alterations in enamel which may have preventive benefits.

  17. Mechanical benefits of conservative restoration for dental fissure caries.

    PubMed

    Zhang, Zhongpu; Zheng, Keke; Li, Eric; Li, Wei; Li, Qing; Swain, Michael V

    2016-01-01

    The principle of minimal intervention dentistry (MID) is to limit removal of carious tooth tissue while maximizing its repair and survival potential. The objective of this study is to explore the fracture resistance of a permanent molar tooth with a fissure carious lesion along with three clinical restoration procedures, namely one traditional and two conservative approaches, based upon MID. The traditional restoration employs extensive surgical removal of enamel and dentine about the cavity to eliminate potential risk of further caries development, while conservative method #1 removes significantly less enamel and infected dentine, and conservative method #2 only restores the overhanging enamel above the cavity and leaves the infected and affected dentine as it was. An extended finite element method (XFEM) is adopted here to analyze the fracture behaviors of both two-dimensional (2D) and three-dimensional (3D) modeling of these four different scenarios. It was found that the two conservative methods exhibited better fracture resistance than the traditional restorative method. Although conservative method #2 has less fracture resistance than method #1, it had significantly superior fracture resistance compared to other restorations. More important, after cavity sealing it may potentially enhance the opportunity for remineralization and improved loading bearing capacity and fracture resistance.

  18. In vitro near-infrared imaging of occlusal dental caries using a germanium-enhanced CMOS camera

    NASA Astrophysics Data System (ADS)

    Lee, Chulsung; Darling, Cynthia L.; Fried, Daniel

    2010-02-01

    The high transparency of dental enamel in the near-infrared (NIR) at 1310-nm can be exploited for imaging dental caries without the use of ionizing radiation. The objective of this study was to determine whether the lesion contrast derived from NIR transillumination can be used to estimate lesion severity. Another aim was to compare the performance of a new Ge enhanced complementary metal-oxide-semiconductor (CMOS) based NIR imaging camera with the InGaAs focal plane array (FPA). Extracted human teeth (n=52) with natural occlusal caries were imaged with both cameras at 1310-nm and the image contrast between sound and carious regions was calculated. After NIR imaging, teeth were sectioned and examined using more established methods, namely polarized light microscopy (PLM) and transverse microradiography (TMR) to calculate lesion severity. Lesions were then classified into 4 categories according to the lesion severity. Lesion contrast increased significantly with lesion severity for both cameras (p<0.05). The Ge enhanced CMOS camera equipped with the larger array and smaller pixels yielded higher contrast values compared with the smaller InGaAs FPA (p<0.01). Results demonstrate that NIR lesion contrast can be used to estimate lesion severity.

  19. The Prevalence of Early Childhood Caries among 24 to 36 Months Old Children of Iran: Using the Novel ICDAS-II Method

    PubMed Central

    Toutouni, Hediyeh; Nokhostin, Mohammad-Reza; Amaechi, Bennett Tochukwu; Zafarmand, Abdol Hamid

    2015-01-01

    Statement of the Problem Early childhood caries is an important oral health issue. Finding its prevalence would predict the need for oral health promotion disciplines for specific age groups.    Purpose The aim of this study was to assess the caries experience of children living in Tehran, Iran. It also would evaluate the impact of gender, ethnicity, and socioeconomic status (SES) on this oral condition. Materials and Method This epidemiological cross-sectional study was based upon stratified cluster random sampling. The samples consisted of 239 children (2- to 3- years old) registered in Tehran’s public healthcare centers for “Healthy Child Program”. Mothers of the recruited children were interviewed for the background data; then children were examined for the oral health status according to ICDAS-II (International Caries Detection and Assessment System) and WHO (World Health Organization) criteria. Statistical analyses were conducted using STATA.11 for SES classification considering six socioeconomic variables, and SPSS.21 for descriptive/analytical analyses. Results Primary Component Analysis (PCA) demonstrated five classes of SES ranging from the lowest to the highest. The distribution of caries-free (CF) children was 10.87%, non-cavitated enamel caries (codes 01-02) were 28.03%, and about 61.1% had cavitated caries (codes 03-06). There was no significant difference in caries experience between the two genders. Cavitated lesions were more prevalent among Kurdish, who also had the least CF children. Caries prevalence, especially code 02, was more among children from 3rd class SES (moderate level). Gender, ethnicity, or SES had no impact on the CF status of the children; however, ethnicity showed significant impact on the prevalence of extensive caries (codes 05-06). Conclusion The result of the present study is indicative of high caries prevalence among 2 to 3 years old children residing in Tehran. It highlights the need for comprehensive oral health

  20. Early dental caries detection using a fibre-optic coupled polarization-resolved Raman spectroscopic system.

    PubMed

    Ko, Alex C-T; Hewko, Mark; Sowa, Michael G; Dong, Cecilia C S; Cleghorn, Blaine; Choo-Smith, Lin-P'ing

    2008-04-28

    A new fibre-optic coupled polarization-resolved Raman spectroscopic system was developed for simultaneous collection of orthogonally polarized Raman spectra in a single measurement. An application of detecting incipient dental caries based on changes observed in Raman polarization anisotropy was also demonstrated using the developed fibre-optic Raman spectroscopic system. The predicted reduction of polarization anisotropy in the Raman spectra of caries lesions was observed and the results were consistent with those reported previously with Raman microspectroscopy. The capability of simultaneous collection of parallel- and cross-polarized Raman spectra of tooth enamel in a single measurement and the improved laser excitation delivery through fibre-optics demonstrated in this new design illustrates its future clinical potential.

  1. Early dental caries detection using a fibre-optic coupled polarization-resolved Raman spectroscopic system

    PubMed Central

    Ko, Alex C.-T.; Hewko, Mark; Sowa, Michael G.; Dong, Cecilia C.S.; Cleghorn, Blaine; Choo-Smith, Lin-P’ing

    2008-01-01

    A new fibre-optic coupled polarization-resolved Raman spectroscopic system was developed for simultaneous collection of orthogonally polarized Raman spectra in a single measurement. An application of detecting incipient dental caries based on changes observed in Raman polarization anisotropy was also demonstrated using the developed fibre-optic Raman spectroscopic system. The predicted reduction of polarization anisotropy in the Raman spectra of caries lesions was observed and the results were consistent with those reported previously with Raman microspectroscopy. The capability of simultaneous collection of parallel-and cross-polarized Raman spectra of tooth enamel in a single measurement and the improved laser excitation delivery through fibre-optics demonstrated in this new design illustrates its future clinical potential. PMID:18545331

  2. Oral Lactobacilli and Dental Caries

    PubMed Central

    Caufield, P.W.; Schön, C.N.; Saraithong, P.; Li, Y.; Argimón, S.

    2015-01-01

    Lactobacilli have been associated with dental caries for over a century. Here, we review the pertinent literature along with findings from our own study to formulate a working hypothesis about the natural history and role of lactobacilli. Unlike most indigenous microbes that stably colonize a host, lactobacilli appear to be planktonic, opportunistic settlers that can gather and multiply only in certain restrictive niches of the host, at least within the oral cavity. We postulate that the following essential requirements are necessary for sustained colonization of lactobacilli in humans: 1) a stagnant, retentive niche that is mostly anaerobic; 2) a low pH milieu; and 3) ready access to carbohydrates. Three sites on the human body meet these specifications: caries lesions, the stomach, and the vagina. Only a handful of Lactobacillus species is found in caries lesions, but they are largely absent in caries-free children. Lactobacilli present in caries lesions represent both a major contributor to caries progression and a major reservoir to the gastrointestinal (GI) tract. We extend the assertion from other investigators that lactobacilli found in the GI tract originate in the oral cavity by proposing that lactobacilli in the oral cavity arise from caries lesions. This, in turn, leads us to reflect on the health implications of the lactobacilli in the mouth and downstream GI and to ponder whether these or any of the Lactobacillus species are truly indigenous to the human GI tract or the oral cavity. PMID:25758458

  3. Wide-Field Raman Imaging of Dental Lesions

    PubMed Central

    Yang, Shan; Li, Bolan; Akkus, Anna; Akkus, Ozan; Lang, Lisa

    2014-01-01

    Detection of dental caries at the onset remains as a great challenge in dentistry. Raman spectroscopy could be successfully applied towards detecting caries since it is sensitive to the amount of the Raman active mineral crystals, the most abundant component of enamel. Effective diagnosis requires full examination of a tooth surface via a Raman mapping. Point-scan Raman mapping is not clinically relevant (feasible) due to lengthy data acquisition time. In this work, a wide-field Raman imaging system was assembled based on a high-sensitivity 2D CCD camera for imaging the mineralization status of teeth with lesions. Wide-field images indicated some lesions to be hypomineralized and others to be hypermineralized. The observations of wide-field Raman imaging were in agreement with point-scan Raman mapping. Therefore, sound enamel and lesions can be discriminated by Raman imaging of the mineral content. In conclusion, wide-field Raman imaging is a potentially useful tool for visualization of dental lesions in the clinic. PMID:24781363

  4. Human enamel structure studied by high resolution electron microscopy

    SciTech Connect

    Wen, S.L. )

    1989-01-01

    Human enamel structural features are characterized by high resolution electron microscopy. The human enamel consists of polycrystals with a structure similar to Ca10(PO4)6(OH)2. This article describes the structural features of human enamel crystal at atomic and nanometer level. Besides the structural description, a great number of high resolution images are included. Research into the carious process in human enamel is very important for human beings. This article firstly describes the initiation of caries in enamel crystal at atomic and unit-cell level and secondly describes the further steps of caries with structural and chemical demineralization. The demineralization in fact, is the origin of caries in human enamel. The remineralization of carious areas in human enamel has drawn more and more attention as its potential application is realized. This process has been revealed by high resolution electron microscopy in detail in this article. On the other hand, the radiation effects on the structure of human enamel are also characterized by high resolution electron microscopy. In order to reveal this phenomenon clearly, a great number of electron micrographs have been shown, and a physical mechanism is proposed. 26 references.

  5. Bacterial Profile of Dentine Caries and the Impact of pH on Bacterial Population Diversity

    PubMed Central

    Kianoush, Nima; Adler, Christina J.; Nguyen, Ky-Anh T.; Browne, Gina V.; Simonian, Mary; Hunter, Neil

    2014-01-01

    Dental caries is caused by the release of organic acids from fermentative bacteria, which results in the dissolution of hydroxyapatite matrices of enamel and dentine. While low environmental pH is proposed to cause a shift in the consortium of oral bacteria, favouring the development of caries, the impact of this variable has been overlooked in microbial population studies. This study aimed to detail the zonal composition of the microbiota associated with carious dentine lesions with reference to pH. We used 454 sequencing of the 16S rRNA gene (V3–V4 region) to compare microbial communities in layers ranging in pH from 4.5–7.8 from 25 teeth with advanced dentine caries. Pyrosequencing of the amplicons yielded 449,762 sequences. Nine phyla, 97 genera and 409 species were identified from the quality-filtered, de-noised and chimera-free sequences. Among the microbiota associated with dentinal caries, the most abundant taxa included Lactobacillus sp., Prevotella sp., Atopobium sp., Olsenella sp. and Actinomyces sp. We found a disparity between microbial communities localised at acidic versus neutral pH strata. Acidic conditions were associated with low diversity microbial populations, with Lactobacillus species including L. fermentum, L. rhamnosus and L. crispatus, being prominent. In comparison, the distinctive species of a more diverse flora associated with neutral pH regions of carious lesions included Alloprevotella tanerrae, Leptothrix sp., Sphingomonas sp. and Streptococcus anginosus. While certain bacteria were affected by the pH gradient, we also found that ∼60% of the taxa associated with caries were present across the investigated pH range, representing a substantial core. We demonstrated that some bacterial species implicated in caries progression show selective clustering with respect to pH gradient, providing a basis for specific therapeutic strategies. PMID:24675997

  6. Bio-Photonic Detection and Quantitative Evaluation Method for the Progression of Dental Caries Using Optical Frequency-Domain Imaging Method

    PubMed Central

    Wijesinghe, Ruchire Eranga; Cho, Nam Hyun; Park, Kibeom; Jeon, Mansik; Kim, Jeehyun

    2016-01-01

    The initial detection of dental caries is an essential biomedical requirement to barricade the progression of caries and tooth demineralization. The objective of this study is to introduce an optical frequency-domain imaging technique based quantitative evaluation method to calculate the volume and thickness of enamel residual, and a quantification method was developed to evaluate the total intensity fluctuation in depth direction owing to carious lesions, which can be favorable to identify the progression of dental caries in advance. The cross-sectional images of the ex vivo tooth samples were acquired using 1.3 μm spectral domain optical coherence tomography system (SD-OCT). Moreover, the advantages of the proposed method over the conventional dental inspection methods were compared to highlight the potential capability of OCT. As a consequence, the threshold parameters obtained through the developed method can be used as an efficient investigating technique for the initial detection of demineralization. PMID:27929440

  7. Effect of the antimicrobial photodynamic therapy on microorganism reduction in deep caries lesions: a systematic review and meta-analysis

    NASA Astrophysics Data System (ADS)

    Ornellas, Pâmela Oliveira; Antunes, Leonardo Santos; Fontes, Karla Bianca Fernandes da Costa; Póvoa, Helvécio Cardoso Corrêa; Küchler, Erika Calvano; Iorio, Natalia Lopes Pontes; Antunes, Lívia Azeredo Alves

    2016-09-01

    This study aimed to perform a systematic review to assess the effectiveness of antimicrobial photodynamic therapy (aPDT) in the reduction of microorganisms in deep carious lesions. An electronic search was conducted in Pubmed, Web of Science, Scopus, Lilacs, and Cochrane Library, followed by a manual search. The MeSH terms, MeSH synonyms, related terms, and free terms were used in the search. As eligibility criteria, only clinical studies were included. Initially, 227 articles were identified in the electronic search, and 152 studies remained after analysis and exclusion of the duplicated studies; 6 remained after application of the eligibility criteria; and 3 additional studies were found in the manual search. After access to the full articles, three were excluded, leaving six for evaluation by the criteria of the Cochrane Collaboration's tool for assessing risk of bias. Of these, five had some risk of punctuated bias. All results from the selected studies showed a significant reduction of microorganisms in deep carious lesions for both primary and permanent teeth. The meta-analysis demonstrated a significant reduction in microorganism counts in all analyses (p<0.00001). Based on these findings, there is scientific evidence emphasizing the effectiveness of aPDT in reducing microorganisms in deep carious lesions.

  8. Comparative in vitro microradiographic effects of resin-modified and autopolymerizing glass ionomers on demineralization of primary and permanent enamel.

    PubMed

    Wandera, A; Garcia, G

    1998-01-01

    The purpose of this study was to compare in vitro effects of resin-modified and autopolymerizing glass ionomer restorative materials on demineralization of primary and permanent human enamel. Thirty primary and permanent enamel specimens measuring approximately 3 x 4 x 4 mm were sectioned and plano-paralleled before random placement of materials: Photac-Fil, a resin-modified glass ionomer; Ketac-Fil, an autopolymerizing glass ionomer; and Tytin, a silver amalgam. After incubation for twenty-four hours, the samples were pH cycled for eight hours at pH 5.0 and sixteen hours at pH 7.2 for a total of two weeks, all at 37 degrees C. The specimens were then subjected to an artificial caries challenge at pH 5.0 for 196 hours. The specimens were embeded in Epon 812 and incubated at 55 degrees C for thirty-six hours. Microsections were produced from each sample and subjected to microradiography and quantitative microdensitometry. Data on lesion depth and mineral content were analyzed by Two Way ANOVA and Student Newman-Keuls Pairwise Multiple Comparison tests. There were significant differences in lesion depth and mineral content between groups (p < 0.05) and between permanent and primary enamel. This study demonstrates that Photac-Fil and Ketac-Fil prevent in vitro demineralization at varying levels in primary and permanent enamel.

  9. Detection of questionable occlusal carious lesions using an electrical bioimpedance method with fractional electrical model

    NASA Astrophysics Data System (ADS)

    Morais, A. P.; Pino, A. V.; Souza, M. N.

    2016-08-01

    This in vitro study evaluated the diagnostic performance of an alternative electric bioimpedance spectroscopy technique (BIS-STEP) detect questionable occlusal carious lesions. Six specialists carried out the visual (V), radiography (R), and combined (VR) exams of 57 sound or non-cavitated occlusal carious lesion teeth classifying the occlusal surfaces in sound surface (H), enamel caries (EC), and dentinal caries (DC). Measurements were based on the current response to a step voltage excitation (BIS-STEP). A fractional electrical model was used to predict the current response in the time domain and to estimate the model parameters: Rs and Rp (resistive parameters), and C and α (fractional parameters). Histological analysis showed caries prevalence of 33.3% being 15.8% hidden caries. Combined examination obtained the best traditional diagnostic results with specificity = 59.0%, sensitivity = 70.9%, and accuracy = 60.8%. There were statistically significant differences in bioimpedance parameters between the H and EC groups (p = 0.016) and between the H and DC groups (Rs, p = 0.006; Rp, p = 0.022, and α, p = 0.041). Using a suitable threshold for the Rs, we obtained specificity = 60.7%, sensitivity = 77.9%, accuracy = 73.2%, and 100% of detection for deep lesions. It can be concluded that BIS-STEP method could be an important tool to improve the detection and management of occlusal non-cavitated primary caries and pigmented sites.

  10. Caries-removal effectiveness of a papain-based chemo-mechanical agent: A quantitative micro-CT study.

    PubMed

    Neves, Aline A; Lourenço, Roseane A; Alves, Haimon D; Lopes, Ricardo T; Primo, Laura G

    2015-01-01

    The aim of this study was to access the effectiveness and specificity of a papain-based chemo-mechanical caries-removal agent in providing minimum residual caries after cavity preparation. In order to do it, extracted carious molars were selected and scanned in a micro-CT before and after caries-removal procedures with the papain-based gel. Similar parameters for acquisition and reconstruction of the image stacks were used between the scans. After classification of the dentin substrate based on mineral density intervals and establishment of a carious tissue threshold, volumetric parameters related to effectiveness (mineral density of removed dentin volume and residual dentin tissue) and specificity (relation between carious dentin in removed volume and initial caries) of this caries-removal agent were obtained. In general, removed dentin volume was similar or higher than the initial carious volume, indicating that the method was able to effectively remove dentin tissue. Samples with an almost perfect accuracy in carious dentin removal also showed an increased removal of caries-affected tissue. On the contrary, less or no affected dentin was removed in samples where some carious tissue was left in residual dentin. Mineral density values in residual dentin were always higher or similar to the threshold for mineral density values in carious dentin. In conclusion, the papain-based gel was effective in removing carious dentin up to a conservative in vitro threshold. Lesion characteristics, such as activity and morphology of enamel lesion, may also influence caries-removal properties of the method.

  11. Microstructure and nanomechanical properties of enamel remineralized with asparagine-serine-serine peptide.

    PubMed

    Chung, Hsiu-Ying; Li, Cheng Che

    2013-03-01

    A highly biocompatible peptide, triplet repeats of asparagine-serine-serine (3 NSS) was designed to regulate mineral deposition from aqueous ions in saliva for the reconstruction of enamel lesions. Healthy human enamel was sectioned and acid demineralized to create lesions, then exposed to the 3 NSS peptide solution, and finally immersed in artificial saliva for 24h. The surface morphology and roughness were examined using scanning electron microscopy (SEM) and atomic force microscopy (AFM), respectively. X-ray diffraction (XRD) was used to identify the phases and crystallinity of the deposited minerals observed on the enamel surface. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) was used to quantitatively analyze the mineral variation by calculating the relative integrated-area of characteristic bands. Nanohardness and elastic modulus measured by nanoindentation at various treatment stages were utilized to evaluate the degree of recovery. Biomimetic effects were accessed according to the degree of nanohardness recovery and the amount of hydroxyapatite deposition. The charged segments in the 3 NSS peptide greatly attracted aqueous ions from artificial saliva to form hydroxyapatite crystals to fill enamel caries, in particular the interrod areas, resulting in a slight reduction in overall surface roughness. Additionally, the deposited hydroxyapatites were of a small crystalline size in the presence of the 3 NSS peptide, which effectively restrained the plastic deformations and thus resulted in greater improvements in nanohardness and elastic modulus. The degree of nanohardness recovery was 5 times greater for remineralized enamel samples treated with the 3 NSS peptide compared to samples without peptide treatment.

  12. Caries diagnosis using laser fluorescence

    NASA Astrophysics Data System (ADS)

    Zanin, Fatima A. A.; Pinheiro, Antonio L. B.; Souza-Campos, Dilma H.; Brugnera, Aldo, Jr.; Pecora, Jesus D.

    2000-03-01

    Caries prevention is a goal to be achieved by dentist in order to promote health. There are several methods used to detect dental caries each one presenting advantages and disadvantages, especially regarding hidden occlusal caries. The improvement of laser technology has permitted the use of laser fluorescence for early diagnosis of hidden occlusal caries. The aim of this study was to assess the efficacy of the use of 655 nm laser light on the detection of hidden occlusal caries. Forty molar teeth from patients of both sexes which ages ranging from 10 - 18 years old were used on this study. Following manufacture's instructions regarding the use of the equipment, the teeth had their occlusal surface examined with the DIAGNOdent. Twenty six of 40 teeth had hidden occlusal caries detected by the DIAGNOdent. However only 17 of these 26 teeth showed radiographic signs of caries the other 9 teeth showed no radiological signs of the lesion. Radiographic examination was able to identify 34,61% of false negative cases. This means that many caries would be left untreated due to the lack of diagnosis using both visual and radiographic examination. The use of the DIAGNOdent was effective in successfully detecting hidden occlusal caries.

  13. Laser-scanned fluorescence of nonlased/normal, lased/normal, nonlased/carious, and lased/carious enamel

    NASA Astrophysics Data System (ADS)

    Zakariasen, Kenneth L.; Barron, Joseph R.; Paton, Barry E.

    1992-06-01

    Research has shown that low levels of CO2 laser irradiation raise enamel resistance to sub-surface demineralization. Additionally, laser scanned fluorescence analysis of enamel, as well a laser and white light reflection studies, have potential for both clinical diagnosis and comparative research investigations of the caries process. This study was designed to compare laser fluorescence and laser/white light reflection of (1) non-lased/normal with lased/normal enamel and (2) non-lased/normal with non-lased/carious and lased/carious enamel. Specimens were buccal surfaces of extracted third molars, coated with acid resistant varnish except for either two or three 2.25 mm2 windows (two window specimens: non-lased/normal, lased/normal--three window specimens: non-lased/normal, non-lased carious, lased/carious). Teeth exhibiting carious windows were immersed in a demineralizing solution for twelve days. Non-carious windows were covered with wax during immersion. Following immersion, the wax was removed, and fluorescence and laser/white light reflection analyses were performed on all windows utilizing a custom scanning laser fluorescence spectrometer which focuses light from a 25 mWatt He-Cd laser at 442 nm through an objective lens onto a cross-section >= 3 (mu) in diameter. For laser/white light reflection analyses, reflected light intensities were measured. A HeNe laser was used for laser light reflection studies. Following analyses, the teeth are sectioned bucco-lingually into 80 micrometers sections, examined under polarized light microscopy, and the lesions photographed. This permits comparison between fluorescence/reflected light values and the visualized decalcification areas for each section, and thus comparisons between various enamel treatments and normal enamel. The enamel specimens are currently being analyzed.

  14. Clinical trial for detection of dental caries using laser-induced fluorescence ratio reference standard

    NASA Astrophysics Data System (ADS)

    Thomas, Shiny Sara; Mohanty, Soumyakant; Jayanthi, J. L.; Varughese, Jolly Mary; Balan, Anitha; Subhash, Narayanan

    2010-03-01

    We present the clinical applicability of fluorescence ratio reference standard (FRRS) to discriminate different stages of dental caries. Toward this, laser-induced autofluorescence emission spectra are recorded in vivo in the 400- to 800-nm spectral range on a miniature fiber optic spectrometer from 65 patients, with a 404-nm diode laser as the excitation source. Autofluorescence spectra of sound teeth consist of a broad emission at 500 nm that is typical of natural enamel, whereas in caries teeth additional peaks are seen at 635 and 680 nm due to emission from porphyrin compounds in oral bacteria. Scatter plots are developed to differentiate sound teeth from enamel caries, sound teeth from dentinal caries, and enamel caries from dentinal caries using the mean fluorescence intensity (FI) and ratios F500/F635 and F500/F680 measured from 25 sites of sound teeth and 65 sites of carious teeth. The sensitivity and specificity of both the FI and FRRS are determined. It is observed that a diagnostic algorithm based on FRRS scatter plots is able to discriminate enamel caries from sound teeth, dentinal caries from sound teeth, and enamel from dentinal caries with overall sensitivities of 85, 100, and 88% and specificities of 90, 100, and 77%, respectively.

  15. Aesthetic approach for anterior teeth with enamel hypoplasia

    PubMed Central

    Martos, Josué; Gewehr, Andréa; Paim, Emanuele

    2012-01-01

    Enamel hypoplasia is a developmental defect of the enamel that is produced by a disturbance in the formation of the organic enamel matrix, clinically visible as enamel defects. Disorders that occur during the stages of enamel development and maturation reduce the amount or thickness of the enamel, resulting in white spots, tiny grooves, depressions and fissures in the enamel surface. The complexity and intensity of the dental deformity lesions will conduct the ideal treatment-associating conservative techniques. This article presents a case report of a restorative treatment of enamel hypoplasia using hybrid composite resin to mask color alteration and enamel defects. An aesthetic appearance that respects the tooth polychromatic and the self-esteem of the patient can be achieved with this approach. PMID:22629075

  16. Dissolution of powdered human enamel suspended in acid solutions at a high solid/solution ratio under a 5% CO2 atmosphere at 20 degrees C.

    PubMed

    Larsen, M J; Pearce, E I; Ravnholt, G

    1997-09-01

    The aim was to examine the nature of enamel dissolution in aqueous suspensions with a high solid/solution ratio and in a CO2-rich atmosphere. Before experimentation, a water-saturated mixture of 95% N2-5% CO2 was passed through the acid solutions for 24 hr. Samples of 2 g of powdered enamel were suspended in 7 ml of either 5 or 10 mmol/l HClO4, with or without 2 parts/10(6) fluoride and kept gently agitated for 24 hr in the above atmosphere. The same enamel samples were repeatedly exposed to fresh acid for 26 runs. All experiments were duplicated. The aqueous phase was analysed after 20 min and 24 hr for calcium, phosphate, fluoride, chloride, sodium and magnesium. It was found that after 20 min the fluoride was invariably taken up in the enamel and the solution was supersaturated with respect to hydroxyapatite with pH ranging 6.7-5.6. During the following 24 hr pH increased further, the supersaturation remained unchanged and the concentrations of calcium and phosphate in solution decreased. In contrast, sodium, magnesium and chloride were released from enamel during the entire period. In the later runs, the supersaturation with respect to hydroxyapatite was only modest and the decrease of calcium and phosphate concentrations limited, as were the release of sodium, magnesium and chloride. It is concluded that despite a CO2-rich atmosphere, calcium, phosphate and carbonate were released from enamel and quickly established a supersaturation with respect to hydroxyapatite with a secondary reprecipitation of mineral. It indicates that within the dental caries lesion in vivo, lesion fluid cannot exist undersaturated with respect to enamel apatite.

  17. Effect of dentifrices on their remineralizing potential in artificial carious lesions: An in situ study

    PubMed Central

    Damle, Satyawan Gangaramji; Bector, Aditi; Damle, Dhanashree; Kaur, Simranjeet

    2016-01-01

    Background: The eventual sequel of dental caries is determined by the dynamic equilibrium between pathological factors which lead to demineralization and protective elements, which in turn leads to remineralization. Remineralization is the natural process for noncavitated demineralized lesions and relies on calcium and phosphate ions assisted by fluoride to rebuild a new surface on existing crystal remnants in subsurface lesions remaining after demineralization. Hence, the present study was designed to evaluate the efficacy of fluoride dentifrices in remineralizing artificial caries-like lesions in situ. Materials and Methods: A double-blind, randomized study with an initial washout period of 7 days was carried out for 3 weeks. Twenty volunteers were enrolled, who wore the intraoral cariogenicity test appliance having enamel slabs incorporated into them, for 3 weeks. 10 participants were instructed to use Group A dentifrice (fluoride) and the other 10 Group B dentifrice (nonfluoride) for brushing their teeth. The enamel slabs were analyzed by surface microhardness testing and scanning electron microscopy (SEM) at 3 intervals. Results: No significant differences was seen in the microhardness values recorded for Group A and Group B at baseline and after demineralization (P > 0.05); however Group B exhibited lesser microhardness compared to Group A, after intra-oral exposure (P < 0.05). In the SEM analysis, the Group A enamel surfaces had more regular and longer crystallites to those of the Group B. Conclusion: Fluoride dentifrices avert the decrease in enamel hardness and loss of minerals from the enamel surface to a large extent as compared to the nonfluoride dentifrices. PMID:26962320

  18. Mineral density of hypomineralised and sound enamel.

    PubMed

    Garot, Elsa; Rouas, Patrick; D'Incau, Emmanuel; Lenoir, Nicolas; Manton, David; Couture-Veschambre, Christine

    2016-06-28

    Molar Incisor Hypomineralisation (MIH) is a structural anomaly that affects the quality of tooth enamel and has important consequences for oral health. The developmentally hypomineralised enamel has normal thickness and can range in colour from white to yellow or brown. The purpose of the present study is to compare the mineral density of hypomineralised and normal enamel. The sample included eight MIH teeth from seven patients. MIH teeth were scanned using high resolution microtomography. Non-parametric statistical tests (Wilcoxon test for paired samples) were carried out. Hypomineralised enamel has decreased mineral density (mean 19%; p < 0.0001) compared to normal enamel. This weak enamel has implications in clinical management of MIH lesions.

  19. Prognosis of caries increment with past caries experience variables.

    PubMed

    van Palenstein Helderman, W H; van't Hof, M A; van Loveren, C

    2001-01-01

    This study aimed to select past caries experience variables as caries predictors and to compare their prognostic accuracy with the variables used in a method of caries prognosis developed in a Swiss child population. The data used for the analyses originated from an 8-year longitudinal study starting in 1980 on caries of 7.5-year-old Dutch children. Stepwise logistic regression analyses provided predictor variables. The newly introduced variables D23fi, D(123)i and D23pifi were interchangeable and the most powerful caries predictors. For the sake of uniformity and ease of application, D23fi (number of fissures of the permanent first molar with non-cavitated or cavitated caries lesions) was chosen as the first variable in the logistic regression equations. The gain in accuracy of the second and third predictor variables (number of sound primary molars and the number of buccal and lingual smooth surfaces of the permanent first molar with non-cavitated or cavitated caries) in the regression equations was limited. The D1 condition of surfaces could be omitted from the prediction models. The present forced three-predictor-regression equations for 7.5-, 9.5- and 11.5-year-old children were evaluated to assess their prognostic performance by using the area under the ROC curve as a measure of prognostic quality. For the present regression equations, the area under the ROC curve was 81-87%, which was higher compared to the Swiss regression equations for caries prognosis.

  20. A construction of standardized near infrared hyper-spectral teeth database: a first step in the development of reliable diagnostic tool for quantification and early detection of caries

    NASA Astrophysics Data System (ADS)

    Bürmen, Miran; Usenik, Peter; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2011-03-01

    Dental caries is a disease characterized by demineralization of enamel crystals leading to the penetration of bacteria into the dentin and pulp. If left untreated, the disease can lead to pain, infection and tooth loss. Early detection of enamel demineralization resulting in increased enamel porosity, commonly known as white spots, is a difficult diagnostic task. Several papers reported on near infrared (NIR) spectroscopy to be a potentially useful noninvasive spectroscopic technique for early detection of caries lesions. However, the conducted studies were mostly qualitative and did not include the critical assessment of the spectral variability of the sound and carious dental tissues and influence of the water content. Such assessment is essential for development and validation of reliable qualitative and especially quantitative diagnostic tools based on NIR spectroscopy. In order to characterize the described spectral variability, a standardized diffuse reflectance hyper-spectral database was constructed by imaging 12 extracted human teeth with natural lesions of various degrees in the spectral range from 900 to 1700 nm with spectral resolution of 10 nm. Additionally, all the teeth were imaged by digital color camera. The influence of water content on the acquired spectra was characterized by monitoring the teeth during the drying process. The images were assessed by an expert, thereby obtaining the gold standard. By analyzing the acquired spectra we were able to accurately model the spectral variability of the sound dental tissues and identify the advantages and limitations of NIR hyper-spectral imaging.

  1. Rampant Caries

    ERIC Educational Resources Information Center

    Guzman-Armstrong, Sandra

    2005-01-01

    Although dental caries in the pediatric and adolescent population has consistently declined in the United States, it is still the most common childhood disease. Dental problems are the number one reason for missing school next to the common cold. Dental caries are an infectious, communicable disease resulting in destruction of tooth structure by…

  2. Keratins as components of the enamel organic matrix.

    PubMed

    Duverger, Olivier; Beniash, Elia; Morasso, Maria I

    2016-01-01

    Dental enamel is the hardest tissue in the human body, and although it starts as a tissue rich in proteins, by the time of eruption of the tooth in the oral cavity only a small fraction of the protein remains. While this organic matrix of enamel represents less than 1% by weight it plays essential roles in improving both toughness and resilience to chemical attacks. Despite the fact that the first studies of the enamel matrix began in the 19th century, its exact composition and mechanisms of its function remain poorly understood. It was proposed that keratin or a keratin-like primitive epithelial component exists in mature enamel, however due to the extreme insolubility of its organic matrix the presence of keratins there was never clearly established. We have recently identified expression of a number of hair keratins in ameloblasts, the enamel secreting cells, and demonstrated their incorporation into mature enamel. Mutation in epithelial hair keratin KRT75 leads to a skin condition called pseudofollicularis barbae. Carriers of this mutation have an altered enamel structure and mechanical properties. Importantly, these individuals have a much higher prevalence of caries. To the best of our knowledge, this is the first study showing a direct link between a mutation in a protein-coding region of a gene and increased caries rates. In this paper we present an overview of the evidence of keratin-like material in enamel that has accumulated over the last 150years. Furthermore, we propose potential mechanisms of action of KTR75 in enamel and highlight the clinical implications of the link between mutations in KRT75 and caries. Finally, we discuss the potential use of keratins for enamel repair.

  3. Abrasion, erosion, and abfraction combined with linear enamel hypoplasia: a case report.

    PubMed

    Boston, D W; al-bargi, H; Bogert, M

    1999-10-01

    Linear enamel hypoplasia is a developmental disturbance of enamel resulting in clinically visible horizontal defects in enamel that are present on eruption of the tooth. Nondevelopmental lesions of the hard tissues of the tooth, including carious, abrasion, erosion, attrition, and abfraction lesions, require varying amounts of time after tooth eruption to develop. Because linear enamel hypoplasia lesions are present on eruption and are exposed to the factors responsible for abrasion, erosion, and abfraction, nondevelopmental lesions could occur within them in any combination. This report describes a patient with multiple teeth with linear enamel hypoplasia lesions containing nondevelopmental defects as well as nondevelopmental defects that occurred separately. Severe pain and a unique lesion morphology were associated with the linear enamel hypoplasia defects. Affected teeth were extracted because of advanced periodontitis and were sectioned to determine the nature of the enamel and dentin lesions.

  4. Recovery of crystallographic texture in remineralized dental enamel.

    PubMed

    Siddiqui, Samera; Anderson, Paul; Al-Jawad, Maisoon

    2014-01-01

    Dental caries is the most prevalent disease encountered by people of all ages around the world. Chemical changes occurring in the oral environment during the caries process alter the crystallography and microstructure of dental enamel resulting in loss of mechanical function. Little is known about the crystallographic effects of demineralization and remineralization. The motivation for this study was to develop understanding of the caries process at the crystallographic level in order to contribute towards a long term solution. In this study synchrotron X-ray diffraction combined with scanning electron microscopy and scanning microradiography have been used to correlate enamel crystallography, microstructure and mineral concentration respectively in enamel affected by natural caries and following artificial demineralization and remineralization regimes. In particular, the extent of destruction and re-formation of this complex structure has been measured. 2D diffraction patterns collected at the European Synchrotron Radiation Facility were used to quantify changes in the preferred orientation (crystallographic texture) and position of the (002) Bragg reflection within selected regions of interest in each tooth slice, and then correlated with the microstructure and local mineral mass. The results revealed that caries and artificial demineralization cause a large reduction in crystallographic texture which is coupled with the loss of mineral mass. Remineralization restores the texture to the original level seen in healthy enamel and restores mineral density. The results also showed that remineralization promotes ordered formation of new crystallites and growth of pre-existing crystallites which match the preferred orientation of healthy enamel. Combining microstructural and crystallographic characterization aids the understanding of caries and erosion processes and assists in the progress towards developing therapeutic treatments to allow affected enamel to regain

  5. Recovery of Crystallographic Texture in Remineralized Dental Enamel

    PubMed Central

    Siddiqui, Samera; Anderson, Paul; Al-Jawad, Maisoon

    2014-01-01

    Dental caries is the most prevalent disease encountered by people of all ages around the world. Chemical changes occurring in the oral environment during the caries process alter the crystallography and microstructure of dental enamel resulting in loss of mechanical function. Little is known about the crystallographic effects of demineralization and remineralization. The motivation for this study was to develop understanding of the caries process at the crystallographic level in order to contribute towards a long term solution. In this study synchrotron X-ray diffraction combined with scanning electron microscopy and scanning microradiography have been used to correlate enamel crystallography, microstructure and mineral concentration respectively in enamel affected by natural caries and following artificial demineralization and remineralization regimes. In particular, the extent of destruction and re-formation of this complex structure has been measured. 2D diffraction patterns collected at the European Synchrotron Radiation Facility were used to quantify changes in the preferred orientation (crystallographic texture) and position of the (002) Bragg reflection within selected regions of interest in each tooth slice, and then correlated with the microstructure and local mineral mass. The results revealed that caries and artificial demineralization cause a large reduction in crystallographic texture which is coupled with the loss of mineral mass. Remineralization restores the texture to the original level seen in healthy enamel and restores mineral density. The results also showed that remineralization promotes ordered formation of new crystallites and growth of pre-existing crystallites which match the preferred orientation of healthy enamel. Combining microstructural and crystallographic characterization aids the understanding of caries and erosion processes and assists in the progress towards developing therapeutic treatments to allow affected enamel to regain

  6. Use of an optical clearing agent to enhance the visibility of subsurface structures and lesions from tooth occlusal surfaces

    NASA Astrophysics Data System (ADS)

    Kang, Hobin; Darling, Cynthia L.; Fried, Daniel

    2016-08-01

    The purpose of this study is to show that optical clearing agents can be used to increase the visibility of deeply penetrating occlusal lesions that have reached the underlying dentin and spread laterally under the enamel. Previous studies have shown that high refractive index fluids can increase the contrast of caries lesions. Extracted teeth with natural occlusal lesions were imaged with optical coherence tomography (OCT) with and without the addition of a transparent vinyl polysiloxane impression material (VPS) currently used in vivo. The relative intensity of the reflectivity from the underlying lesion area for each sample was measured before and after application of the VPS. Lesion presence was confirmed with polarized light microscopy and microradiography. Application of VPS significantly increased (P<0.0001) the integrated reflectivity of subsurface dentinal lesions. This study shows that optical clearing agents can be used to increase the optical penetration and the visibility of subsurface lesions and the dentinal-enamel junction under sound and demineralized enamel in OCT images.

  7. Effect of dentifrice containing fluoride and/or baking soda on enamel demineralization/remineralization: an in situ study.

    PubMed

    Cury, J A; Hashizume, L N; Del Bel Cury, A A; Tabchoury, C P

    2001-01-01

    The additive effect of baking soda on the anticariogenic effect of fluoride dentifrice is not well established. To evaluate it, a crossover in situ study was done in three phases of 28 days. Volunteers, using acrylic palatal appliances containing four human enamel blocks, two sound (to evaluate demineralization) and two with artificial caries lesions (to evaluate remineralization), took part in this study. During each phase, 10% sucrose solution was dripped (3 times a day) only onto the sound blocks. After 10 min, a slurry of placebo, fluoride (F) or fluoride and baking soda (F+NaHCO(3)) dentifrice was dripped onto all enamel blocks. The results showed a higher F concentration in dental plaque formed during treatment with F+NaHCO(3) than placebo (p<0.05), but the difference related to F dentifrice was not significant. The enamel demineralization was lower, and remineralization was greater, after treatment with F+NaHCO(3) than placebo (p<0.05), but the difference related to F dentifrice was not significant. The data suggest that baking soda neither improves nor impairs the effect of F dentifrice on reduction of demineralization and enhancement of remineralization of enamel.

  8. Guided fluorescence diagnosis of childhood caries: preliminary measures correlate with depth of carious decay

    NASA Astrophysics Data System (ADS)

    Timoshchuk, Mari-Alina; Zhang, Liang; Dickinson, Brian A.; Ridge, Jeremy S.; Kim, Amy S.; Baltuck, Camille T.; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    2014-02-01

    The current rise in childhood caries worldwide has increased the demand for portable technologies that can quickly and accurately detect and diagnose early stage carious lesions. These lesions, if identified at an early stage, can be reversed with remineralization treatments, education, and improvements in home care. A multi-modal optical prototype for detecting and diagnosing occlusal caries demineralization in vivo has been developed and pilot tested. The device uses a 405-nm laser as a scanned illumination source to obtain high resolution and high surface contrast reflectance images, which allows the user to quickly image and screen for any signs of demineralized enamel. When a suspicious region is located, the device can be switched to perform dual laser fluorescence spectroscopy using 405-nm and 532-nm laser excitations. These spectra are used to compute an auto-fluorescence (AF) ratio of the suspicious region and the percent difference of AF ratios from a healthy region of the same tooth. The device was tested on 7 children's teeth in vivo with clinically diagnosed carious lesions. Lesion depth was then visually estimated from the video image using the 405-nm scanned light source, and within a month the maximum drill depth was assessed by a clinician. The researcher and clinicians were masked from previous measurements in a blinded study protocol. Preliminary results show that the ratiometric percent difference measurement of the AF spectrum of the tooth correlates with the severity of the demineralization as assessed by the clinician after drilling.

  9. Dental Caries

    PubMed Central

    Burgess, Ralph C.

    1988-01-01

    Dental caries is one of the most prevalent diseases afflicting mankind. It reached a peak in the 1950s but has been declining drastically in recent years in children and young adults. This article describes the three contributing factors in dental caries: microbial plaque, tooth susceptibility, and diet, and discusses practical preventive measures which help to reduce caries incidence. Some of these, such as vaccines and antimicrobial varnishes, are still in the research stages, while others, such as sucrose substitutes, low-calorie sweeteners, and limitation of frequency of sugar snacks are well established and can be promoted by family physicians. PMID:21253193

  10. Effect of pH of amine fluoride containing toothpastes on enamel remineralization in vitro

    PubMed Central

    Arnold, Wolfgang H; Haase, Anabel; Hacklaender, Julia; Gintner, Zeno; Bánóczy, Jolan; Gaengler, Peter

    2007-01-01

    Background One of the important factors of the demineralization and remineralization equilibrium of enamel is the pH of the surrounding solutions. Effort has been laid in the formulation of different fluoride compounds and the fluoride content in toothpastes but much less is known about the influence of the pH of the toothpastes on their effectiveness. It was therefore the aim of this study to investigate the influence of different pH levels on enamel remineralization in an in vitro experiment using polarization light microscopy and EDX quantitative element analysis. Methods A 5 × 5 mm window on the enamel surface of 40 caries free extracted human premolars was demineralized in a hydroxyethylcellulose solution at pH 4.8. The teeth were divided into 8 groups and the lower half of the window was covered with varnish serving as control. Each group was then immersed in toothpaste slurry containing amine fluoride (1400 ppm) at pH 4.1, 4.5, 5.1 and 6.9 or control toothpaste slurry without fluoride at pH 4.3, 4.7, 5.3 and 7.0. Serial sections were cut through the lesions and investigated with polarization light microscopy and quantitative EDX element analysis. Results The PLM results showed a decreased porous volume of the body of the lesion after incubation with fluoridated toothpaste at pH 4.53 and 5.16. No differences between the experimental window and the control window were found in the other groups. The quantitative element analysis showed no differences in the element content of any of the groups. Conclusion From the results it can be concluded that slightly acidified fluoridated dentifrices may have a certain positive effect on enamel remineralization. PMID:17941981

  11. Fluorine uptake into human enamel around a fluoride-containing dental material during cariogenic pH cycling

    NASA Astrophysics Data System (ADS)

    Komatsu, H.; Yamamoto, H.; Nomachi, M.; Yasuda, K.; Matsuda, Y.; Murata, Y.; Kijimura, T.; Sano, H.; Sakai, T.; Kamiya, T.

    2007-07-01

    the enamel adjacent to the material remained a caries inhibition zone due to low rate of demineralization. With caries progression, fluorine accumulated in the subsurface of the caries lesion, while the outermost surface of the caries lesion gradually dissolved under increasing pH cycling. The data obtained using PIGE (TIARA, JAPAN) technique were useful to understand the fluorine benefit for preventing dental caries by means of fluoride-containing dental materials.

  12. In vitro remineralization of enamel by polymeric amorphous calcium phosphate composite: Quantitative micro-radiographic study

    PubMed Central

    Langhorst, S.E.; O'Donnell, J.N.R.; Skrtic, D.

    2009-01-01

    Objective: This study explores the efficacy of an experimental orthodontic amorphous calcium phosphate (ACP) composite to remineralize in vitro subsurface enamel lesions microradiographically similar to those seen in early caries. Methods: Lesions were artificially created in extracted human molars. Single tooth sections a minimum of 120 μm thick were cut and individually placed in holders exposing only the carious enamel surface. The exposed surfaces were either left untreated (control) or coated with a 1 mm thick layer of the experimental ACP composite (mass fraction 40 % zirconiahybridized ACP and 60 % photo-activated resin), or a commercial fluoride-releasing orthodontic cement. The composite-coated sections were then photo-cured and microradiographic images were taken of all three groups of specimens before the treatment. Specimens were then cyclically immersed in demineralizing and remineralizing solutions for one month at 37 °C to simulate the pH changes occurring in the oral environment. Microradiographs of all specimens were taken before and after treatment. Results: Quantitative digital image analysis of matched areas from the contact microradiographs taken before and after treatment indicated higher mineral recovery with ACP composites compared to the commercial orthodontic F-releasing cement (14.4 % vs. 4.3 %, respectively), while the control specimens showed an average of 55.4 % further demineralization. Significance: Experimental ACP composite efficiently established mineral ion transfer throughout the body of the lesions and restored the mineral lost due to acid attack. It can be considered a useful adjuvant for the control of caries in orthodontic applications. PMID:19215975

  13. Polarization resolved near-IR imaging of sound and carious dental enamel

    NASA Astrophysics Data System (ADS)

    Darling, Cynthia L.; Chan, Kenneth H.; Fried, Daniel

    2011-03-01

    A thorough understanding of how polarized near-IR light is reflected from and transmitted through sound and carious dental hard tissues is important for the development of optical imaging devices. New optical imaging tools employing non-ionizing radiation are needed for the detection and assessment of dental caries. In this investigation, an automated system was developed to collect images for the full 16-element Mueller Matrix. The polarized light was controlled by linear polarizers and liquid crystal retarders and the 36 images were acquired as the polarized near-IR light is reflected from the occlusal surface or transmitted through thin sections of extracted human whole teeth. Previous near-IR imaging studies suggest that polarization imaging can be exploited to obtain higher contrast images of early dental caries due to the rapid depolarization of incident polarized light by the highly scattering areas of decay. In this study, the reflectance from tooth occlusal surfaces with demineralization and transmitted light through tooth thin sections with caries lesions were investigated. Major differences in the Mueller matrix elements were observed in both sound and demineralized enamel. This study suggests that polarization resolved optical imaging can be exploited to obtain higher contrast images of dental decay.

  14. Efficacy of Concomitant Therapy with Fluoride and Chlorhexidine Varnish on Remineralization of Incipient Lesions in Young Children

    PubMed Central

    Tandon, Shobha; Nayak, Rashmi; Ratnanag, P Venkat; Prajapati, Deepesh; Kamath, Namitha

    2016-01-01

    Aim To assess the effect of combined use of chlorhexidine and fluoride varnish on the remineralization of incipient carious lesions in young children. Materials and methods Twenty caries-active children (80 lesions) were randomly divided into four groups and subjected to initial examination. Caries status was assessed visually and with the aid of DIAGNOdent. Baseline enamel biopsies were obtained. Subjects of groups I and II received fluoride and chlorhexidine varnish respectively. Group III received both fluoride and chlorhexidine varnish alternatively, for a period of 4 weeks. Group IV served as the control. At 3-month follow-up, the incipient lesions were assessed again with DIAGNOdent and enamel biopsy. Results Increased calcium, phosphate, and fluoride levels were noticed in groups I, II, III compared to group IV, at the 3-month follow-up (p < 0.001). Conclusion The combined therapy with fluoride and chlorhex-idine varnish may be considered an alternative therapy for early reversal of incipient lesions. How to cite this article Naidu S, Tandon S, Nayak R, Ratnanag PV, Prajapati D, Kamath N. Efficacy of Concomitant Therapy with Fluoride and Chlorhexidine Varnish on Remineralization of Incipient Lesions in Young Children. Int J Clin Pediatr Dent 2016;9(4):296-302. PMID:28127159

  15. Clinical validation of the use of fluorescence for the early detection of dental caries

    NASA Astrophysics Data System (ADS)

    Stookey, George K.; Isaacs, Roger L.; Ferreira Zandona, Andrea G.; Ando, Masatoshi; Gonzalez, Carlos; Mau, Melissa S.; Kelly, Sue A.; Analoui, Mostafa

    1999-05-01

    A clinical investigation was conducted in children to validate the use of fluorescence for the early detection of dental caries. A total of 150 children were examined for the presence of dental caries at baseline and at 4-month intervals for one year using conventional visual-tactile with and without a dental explorer, electrical conductivity and light fluorescence methods on the occlusal, buccal and lingual tooth surfaces. Interproximal tooth surfaces were examined using conventional film and direct digital radiography at baseline and 12 months. Validation of the clinical methods was performed by the histologic examination of exfoliated primary teeth. The results indicate that visual-tactile examinations with an explorer detected more carious lesions than similar examinations without an explorer. The use of quantitative light fluorescence permitted the detection of a substantially greater number of enamel lesions or demineralized areas than the conventional visual-tactile-radiographic diagnostic procedure. Further, the use of the quantitative light fluorescence permitted the monitoring of both the progression of regression of early carious lesions.

  16. Dental depth profilometry using simultaneous frequency-domain infrared photothermal radiometry and laser luminescence for the diagnosis of dental caries

    NASA Astrophysics Data System (ADS)

    Nicolaides, Lena; Garcia, Jose A.; Mandelis, Andreas; Abrams, Stephen H.

    2001-04-01

    Frequency-domain IR photothermal radiometry is introduced as a dynamic dental diagnostic tool and its main features are compared with modulated laser luminescence for quantifying sound and carious enamel or dentin. Dental caries found in the fissures or grooves of teeth is very difficult to diagnose or quantify with the present clinical techniques. Visual examination and dental radiographs do not detect the presence of decay until there has been significant carious destruction of the tooth. A high-spatial-resolution dynamic experimental imaging set-up, which can provide simultaneous measurements of laser-induced frequency-domain IR photothermal radiometric and luminescence signals form defects in teeth, was developed. Following optical absorption of laser photons, the new set-up can monitor simultaneously and independently the non-radiative conversion, and the radiative de-excitation in turbid media such as hard dental tissue. This work is intended to show the complementarity between modulated luminescence and photothermal frequency scans in detecting carious lesions in teeth. A sound extracted molar with a dentin-enamel interface was introduced to examine the depth profilometric abilities of the method. Occlusal surfaces of teeth with potential areas of demineralization or carious destruction in the fissures were examined and compared to the signals produced by the sound enamel establishing the depth profilometric abilities of the method. The significance to clinical dentistry lies in the potential of this technique to detect and monitor early carious lesions in the pits and fissures of teeth.

  17. Light-emitting diode and laser fluorescence-based devices in detecting occlusal caries

    NASA Astrophysics Data System (ADS)

    Rodrigues, Jonas A.; Hug, Isabel; Neuhaus, Klaus W.; Lussi, Adrian

    2011-10-01

    The aim of this study was to assess the performance of two light-emitting diode (LED)- and two laser fluorescence-based devices in detecting occlusal caries in vitro. Ninety-seven permanent molars were assessed twice by two examiners using two LED- (Midwest Caries - MID and VistaProof - VP) and two laser fluorescence-based (DIAGNOdent 2095 - LF and DIAGNOdent pen 2190 - LFpen) devices. After measuring, the teeth were histologically prepared and classified according to lesion extension. At D1 the specificities were 0.76 (LF and LFpen), 0.94 (MID), and 0.70 (VP); the sensitivities were 0.70 (LF), 0.62 (LFpen), 0.31 (MID), and 0.75 (VP). At D3 threshold the specificities were 0.88 (LF), 0.87 (LFpen), 0.90 (MID), and 0.70 (VP); the sensitivities were 0.63 (LF and LFpen), 0.70 (MID), and 0.96 (VP). Spearman's rank correlations with histology were 0.56 (LF), 0.51 (LFpen), 0.55 (MID), and 0.58 (VP). Inter- and intraexaminer ICC values were high and varied from 0.83 to 0.90. Both LF devices seemed to be useful auxiliary tools to the conventional methods, presenting good reproducibility and better accuracy at D3 threshold. MID was not able to differentiate sound surfaces from enamel caries and VP still needs improvement on the cut-off limits for its use.

  18. Evaluation of cross-polarized near infrared hyperspectral imaging for early detection of dental caries

    NASA Astrophysics Data System (ADS)

    Usenik, Peter; Bürmen, Miran; Fidler, Aleš; Pernuš, Franjo; Likar, Boštjan

    2012-01-01

    Despite major improvements in dental healthcare and oral hygiene, dental caries remains one of the most prevalent oral diseases and represents the primary cause of oral pain and tooth loss. The initial stages of dental caries are characterized by demineralization of enamel crystals and are difficult to diagnose. Near infrared (NIR) hyperspectral imaging is a new promising technique for detection of early changes in the surfaces of carious teeth. This noninvasive imaging technique can characterize and differentiate between the sound tooth surface and initial or advanced tooth caries. The absorbing and scattering properties of dental tissues reflect in distinct spectral features, which can be measured, quantified and used to accurately classify and map different dental tissues. Specular reflections from the tooth surface, which appear as bright spots, mostly located around the edges and the crests of the teeth, act as a noise factor which can significantly interfere with the spectral measurements and analysis of the acquired images, degrading the accuracy of the classification and diagnosis. Employing cross-polarized imaging setup can solve this problem, however has yet to be systematically evaluated, especially in broadband hyperspectral imaging setups. In this paper, we employ cross-polarized illumination setup utilizing state-of-the-art high-contrast broadband wire-grid polarizers in the spectral range from 900 nm to 1700 nm for hyperspectral imaging of natural and artificial carious lesions of various degrees.

  19. Inhibition of caries in vital teeth by CO2 laser treatment

    NASA Astrophysics Data System (ADS)

    Rechmann, Peter; Fried, Daniel; Le, Charles Q.; Nelson, Gerald; Rapozo-Hilo, Marcia; Rechmann, Beate M. T.; Featherstone, John D. B.

    2008-02-01

    In multiple well-controlled laboratory studies enhancing caries resistance of enamel has been successfully reported using short-pulsed 9.6 µm CO2 laser irradiation. The aim of this study was to prove in a short term clinical pilot trial that the use of the CO2 laser will significantly inhibit the formation of carious lesions around orthodontic brackets in vivo in comparison to a non-irradiated control area. Twelve subjects scheduled for extraction of premolars for orthodontic treatment reasons with an average age of 14.6 years were recruited for the 4-week study. Orthodontic brackets were placed on those premolars with a conventional composite resin (Transbond XT, 3M Unitek, REF 712-035) and a defined area next to the bracket was irradiated with a CO2 laser, Pulse System, Inc (PSI) (Model #LPS-500, Los Alamos, New Mexico), wavelength 9.6 μm, pulse duration 20 μs, pulse repetition rate 20 Hz, beam diameter 1,100 μm, average fluence 4.31 +/- 0.11 J/cm2, 20 laser pulses per spot. Premolars were extracted after four weeks for a quantitative assessment of demineralization by cross sectional microhardness testing. The relative mineral loss ΔZ (vol% x µm) for the laser treated enamel was 402 +/- 85 (SE) while the control area showed a significantly higher mineral loss (mean ΔZ 738 +/- 131; P=0.04, unpaired t-test). The laser treatment produced a 46% demineralization inhibition around the orthodontic brackets in comparison to the non-laser treated areas. This study showed, for the first time that a pulsed 9.6 µm CO2 laser works for the prevention of dental caries in the enamel in vital teeth in human mouths.

  20. The VicGeneration study - a birth cohort to examine the environmental, behavioural and biological predictors of early childhood caries: background, aims and methods

    PubMed Central

    2010-01-01

    Background Dental caries (decay) during childhood is largely preventable however it remains a significant and costly public health concern, identified as the most prevalent chronic disease of childhood. Caries in children aged less than five years (early childhood caries) is a rapid and progressive disease that can be painful and debilitating, and significantly increases the likelihood of poor child growth, development and social outcomes. Early childhood caries may also result in a substantial social burden on families and significant costs to the public health system. A disproportionate burden of disease is also experienced by disadvantaged populations. Methods/Design This study involves the establishment of a birth cohort in disadvantaged communities in Victoria, Australia. Children will be followed for at least 18 months and the data gathered will explore longitudinal relationships and generate new evidence on the natural history of early childhood caries, the prevalence of the disease and relative contributions of risk and protective biological, environmental and behavioural factors. Specifically, the study aims to: 1. Describe the natural history of early childhood caries (at ages 1, 6, 12 and 18 months), tracking pathways from early bacterial colonisation, through non-cavitated enamel white spot lesions to cavitated lesions extending into dentine. 2. Enumerate oral bacterial species in the saliva of infants and their primary care giver. 3. Identify the strength of concurrent associations between early childhood caries and putative risk and protective factors, including biological (eg microbiota, saliva), environmental (fluoride exposure) and socio-behavioural factors (proximal factors such as: feeding practices and oral hygiene; and distal factors such as parental health behaviours, physical health, coping and broader socio-economic conditions). 4. Quantify the longitudinal relationships between these factors and the development and progression of early

  1. Near-IR imaging of interproximal lesions from occlusal surfaces and the influence of stains and plaque

    NASA Astrophysics Data System (ADS)

    Fried, Daniel; Bühler, Christopher M.; Ngaotheppitak, Patara; Darling, Cynthia L.

    2006-02-01

    Dental enamel manifests high transparency in the near-IR (NIR). Our previous work demonstrated that NIR light at 1310-nm is ideally suited for the transillumination of interproximal dental caries (dental decay in between teeth) and that it can also be used to image decay in the pits and fissures of the occlusal (biting) surfaces of posterior teeth where most new dental decay occurs. Early occlusal lesions cannot be detected by x-rays during the early stages of lesion development due to the overlapping topography of the crown of the tooth. Stains and non-calcified plaque are not visible in the NIR enabling better discrimination of demineralized areas. We also demonstrate that interproximal lesions can be imaged from the occlusal surface (from above). Moreover, multiple illumination and detector angles can be exploited for optimal contrast between caries and sound tissue. These measurements suggest that NIR imaging offers significant advantages over the conventional visual, tactile and radiographic caries detection methods and other optical caries detection and imaging techniques.

  2. Thermophotonic lock-in imaging of early demineralized and carious lesions in human teeth

    NASA Astrophysics Data System (ADS)

    Tabatabaei, Nima; Mandelis, Andreas; Amaechi, Bennett Tochukwu

    2011-07-01

    As an extension of frequency-domain photothermal radiometry, a novel dental-imaging modality, thermophotonic lock-in imaging (TPLI), is introduced. This methodology uses photothermal wave principles and is capable of detecting early carious lesions and cracks on occlusal and approximal surfaces as well as early caries induced by artificial demineralizing solutions. The increased light scattering and absorption within early carious lesions increases the thermal-wave amplitude and shifts the thermal-wave centroid, producing contrast between the carious lesion and the intact enamel in both amplitude and phase images. Samples with artificial and natural occlusal and approximal caries were examined in this study. Thermophotonic effective detection depth is controlled by the modulation frequency according to the well-known concept of thermal diffusion length. TPLI phase images are emissivity normalized and therefore insensitive to the presence of stains. Amplitude images, on the other hand, provide integrated information from deeper enamel regions. It is concluded that the results of our noninvasive, noncontacting imaging methodology exhibit higher sensitivity to very early demineralization than dental radiographs and are in agreement with the destructive transverse microradiography mineral density profiles.

  3. Developmental enamel defects in the primary dentition: aetiology and clinical management.

    PubMed

    Salanitri, S; Seow, W K

    2013-06-01

    Developmental enamel defects, presenting as enamel hypoplasia or opacities are caused by damage or disruption to the developing enamel organ as a result of inherited and acquired systemic conditions. The high prevalence of these defects in the primary dentition demonstrates the vulnerability of the teeth to changes in the pre- and postnatal environment. The presence of enamel hypoplasia increases the risk of primary teeth to early childhood caries and tooth wear as the defective enamel is thinner, more plaque retentive and less resistant to dissolution in acid compared to normal enamel. The purpose of this paper was to critically review the aetiology and clinical complications of developmental enamel defects in the primary dentition and propose recommendations for the clinical management of affected teeth.

  4. Staining of residual caries under freshly-packed amalgam restorations exposed to tea/chlorhexidine in vitro.

    PubMed

    Kidd, E A; Joyston-Bechal, S; Smith, M M

    1990-08-01

    Discoloration around restorations may lead practitioners to suspect recurrent caries. Dentists, using conventional optical and tactile criteria, often fail to render the enamel-dentine junction completely caries-free during cavity preparation. The aim of the present laboratory study was to test the hypothesis that such residual caries could take up stain from tea and hence affect clinical judgement on the presence of recurrent disease. Cavities were prepared in freshly extracted carious teeth and restored with amalgam. Specimens were then temperature cycled in tea and chlorhexidine or in tea alone to encourage leakage. Subsequent removal of restorations showed staining of parts of the enamel-dentine junctions and histological examination showed these stained areas to correspond to areas of demineralization. Similarly prepared caries-free teeth showed no such staining. Thus residual caries in teeth with leaking restorations can, in the laboratory, take up stain. If this were to happen in vivo, stained residual caries could subsequently be misdiagnosed as recurrent caries.

  5. Digital radiographic measurement of approximal caries progression in fluoridated and non-fluoridated areas of Rio de Janeiro, Brazil.

    PubMed

    Lawrence, H P; Benn, D K; Sheiham, A

    1997-12-01

    The effect of fluoridation on approximal caries progression was investigated using serial digitized bitewing images and conventional film images of 290 12-16-year-old schoolchildren who were lifetime residents of either Rio de Janeiro (a fluoridated area) or Mangaratiba and Angra dos Reis (non-fluoridated areas) in the state of Rio de Janeiro, Brazil. One examiner scored a maximum of 28 approximal surfaces of posterior teeth per subject using both methods. The intraexaminer reliability for rating lesion depth with digital images was comparable with that of the conventional bitewing films (namely, intraclass correlation of 0.99 and weighted Kappa scores of 0.82, respectively). Approximal surface D1S was 3.17 +/- 0.25 (sx) in fluoridated areas and 6.64 +/- 0.44 in non-fluoridated areas. After 1 year, the rate of caries progression in approximal surfaces was significantly lower in the fluoridated areas (0.54 +/- 0.14) as compared with the non-fluoridated areas (1.41 +/- 0.20) using Pitts' scoring system for conventional bitewing radiographs (P < 0.001). Similarly, the digital radiographic method was able to detect subtle differences in approximal caries progression in the enamel and the dentin (overall mean: 0.34 mm/year in fluoridated areas vs 0.49 mm/year in non-fluoridated areas, P < 0.05). The two radiographic methods were strongly correlated (rs = 0.7). Assuming a constant rate over time, these results indicate that lesion progression from the outer half of the enamel into the outer half of the dentin takes approximately 3-4 years in schoolchildren from the fluoridated areas compared to 2 1/2 years in the non-fluoridated areas.

  6. In vitro evaluation of casein phosphopeptide-amorphous calcium phosphate effect on the shear bond strength of dental adhesives to enamel

    PubMed Central

    Shadman, Niloofar; Ebrahimi, Shahram Farzin; Shoul, Maryam Azizi; Sattari, Hasti

    2015-01-01

    Background: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is applied for remineralization of early caries lesions or tooth sensitivity conditions and may affect subsequent resin bonding. This in vitro study investigated the effect of CPP-ACP on the shear bond strength of dental adhesives to enamel. Materials and Methods: Sixty extracted human molar teeth were selected and randomly divided into three groups and six subgroups. Buccal or lingual surfaces of teeth were prepared to create a flat enamel surface. Adhesives used were Tetric N-Bond, AdheSE and AdheSE One F. In three subgroups, before applying adhesives, enamel surfaces were treated with Tooth Mousse CPP-ACP for one hour, rinsed and stored in 37°C temperature with 100% humidity. This procedure was repeated for 5 days and then adhesives were applied and Tetric N-Ceram composite was adhered to the enamel. This procedure was also fulfilled for the other three subgroups without CPP-ACP treatment. After 24 hour water storage, samples were tested for shear bond strength test in a universal testing machine. Failure modes were determined by stereomicroscope. Data were analyzed by t-test and one-way analysis of variance with P < 0.05 as the level of significance. Results: In comparison between applied and non-applied CPP-ACP subgroups, there was no significant decrease in the shear bond strength to enamel only in Tetric N-Bond (P > 0.05). In non-applied CPP-ACP subgroups, there were statistically significant differences among all subgroups. Tetric N-Bond had the highest and AdheSE One F had the lowest shear bond strength. Conclusion: CPP-ACP application reduces the shear bond strength of AdheSE and AdheSE One F to enamel but not Tetric N-Bond. PMID:25878683

  7. Developmental Defects of Enamel in Children with Intellectual Disability

    PubMed Central

    Erika, Vesna; Modrić; Karlović, Zoran

    2016-01-01

    Objectives To investigate the frequency of developmental defects of enamel (DDE) in children with intellectual disability. Subjects and methods Children aged 5–18 years (72 children with intellectual disabilities and 72 controls) were included in the study. All the teeth were screened for developmental defects of enamel using the modified Developmental defects of enamel (mDDE) index. Results Out of the 72 children with intellectual disabilities in this study, 20 (27.78%) presented dental defects of enamel, compared with 8 (11.11%) of those in the control group, which was considered statistically significant (p = 0.021). The majority of children in both groups had white demarcated opacities. Children in both groups were more likely to have maxillary teeth affected than the mandibular teeth and the asymmetrical demarcated enamel defects were more common than the symmetric ones. Majority of opacities in children in both groups were on the maxillary incisors. Conclusions Children with intellectual disabilities have more developmental defects of enamel than children in the control group. Enamel defects increase caries risk and cause reduction in enamel mechanical properties leading to restoration failures. PMID:27688428

  8. Thermophotonic lock-in imaging: a novel early caries detection and imaging modality

    NASA Astrophysics Data System (ADS)

    Tabatabaei, Nima; Mandelis, Andreas; Amaechi, Bennett T.

    2011-03-01

    Using photothermal wave principles and as an extension to the frequency-domain photothermal radiometry, a novel dental imaging modality, thermophotonic lock-in imaging (TPLI), is introduced. In order to assess the capabilities of the proposed methodology samples with natural and artificially-generated caries were examined and the results were compared with the destructive transverse microradiography density profiles. It was found that the increased light scattering and absorption within early carious lesions increases the thermal-wave amplitude and shifts the thermal-wave centroid, producing contrast between the carious lesion and the intact enamel in both amplitude and phase images. Phase images are emissivity normalized and therefore insensitive to the presence of stain. Amplitude images provide integrated information from deeper enamel regions. It was concluded that the results of our non-invasive, non-contacting imaging methodology exhibit significantly higher sensitivity to very early demineralization than dental radiographs and are in agreement with the destructive transverse microradiography mineral density profiles.

  9. Caries, Periodontal Disease, Supernumerary Teeth and Other Dental Disorders in Swedish Wild Boar (Sus scrofa).

    PubMed

    Malmsten, A; Dalin, A-M; Pettersson, A

    2015-07-01

    Between January and December 2013, the dental and periodontal health of 99 Swedish wild boars (Sus scrofa) was investigated. Sampling occurred in conjunction with routine hunting at six large estates in the southern and middle parts of Sweden. All six of the estates use supplemental feeding. The weight of the animals, their sex and their dates of death were noted. Age was estimated using tooth eruption and tooth replacement patterns. The oral cavity was inspected and abnormalities were recorded on a dental chart modified for wild boars. The findings included supernumerary teeth, absence of teeth, mild class II malocclusion, severe tooth wear, periodontitis, calculus, caries, tooth fractures and the presence of enamel defects. Swedish wild boars suffer from different dental lesions and the impact of supplemental feeding on dental and periodontal health is still to be investigated.

  10. Selective removal of demineralized enamel using a CO2 laser coupled with near-IR reflectance imaging

    NASA Astrophysics Data System (ADS)

    Tom, Henry; Chan, Kenneth H.; Saltiel, Daniel; Fried, Daniel

    2015-02-01

    Detection and diagnosis of early dental caries lesions can be difficult due to variable tooth coloration, staining of the teeth and poor contrast between sound and demineralized enamel. These problems can be overcome by using near-infrared (NIR) imaging. Previous studies have demonstrated that lasers can be integrated with NIR imaging devices, allowing image-guided ablation. The aim of this study was to demonstrate that NIR light at 1500 - 1700 nm can be used to guide a 9.3-μm CO2 laser for the selective ablation of early demineralization on tooth occlusal surfaces. The occlusal surfaces of ten sound human molars were used in this in-vitro study. Shallow simulated caries lesions of varying depth and position were produced on tooth occlusal surfaces using a demineralization solution. Sequential NIR reflectance images at 1500 - 1700 nm were used to guide the laser for selective ablation of the lesion areas. Digital microscopy and polarization sensitive optical coherence tomography (PS-OCT) were used to assess the selectivity of removal. This study demonstrates that high contrast NIR reflectance images can be used for the image-guided laser ablation of early demineralization from tooth occlusal surfaces.

  11. Detection of early caries by laser-induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Sasazawa, Shuhei; Kakino, Satoko; Matsuura, Yuji

    2015-07-01

    To improve sensitivity of dental caries detection by laser-induced breakdown spectroscopy (LIBS) analysis, it is proposed to utilize emission peaks in the ultraviolet. We newly focused on zinc whose emission peaks exist in ultraviolet because zinc exists at high concentration in the outer layer of enamel. It was shown that by using ratios between heights of an emission peak of Zn and that of Ca, the detection sensitivity and stability are largely improved. It was also shown that early caries are differentiated from healthy part by properly setting a threshold in the detected ratios. The proposed caries detection system can be applied to dental laser systems such as ones based on Er:YAG-lasers. When ablating early caries part by laser light, the system notices the dentist that the ablation of caries part is finished. We also show the intensity of emission peaks of zinc decreased with ablation with Er:YAG laser light.

  12. The Health of Naval Recruits: Dental Caries.

    DTIC Science & Technology

    1980-05-01

    the distance from the dentino- enamel junction to the pulp . C-lesions (CLES) extended one-fourth to three-fourths through dentin; urgent or U-lesions...not affected by decay, fillings, or missing due to decay. Teeth missing due to trauma or orthodontically required removal were not included in SAR or

  13. Prevention of Enamel Adjacent to Bracket Demineralization Following Carbon Dioxide Laser Radiation and Titanium Tetra Fluoride Solution Treatment: An In Vitro Study

    PubMed Central

    Mirhashemi, Amir Hossein; Hakimi, Sina; Ahmad Akhoundi, Mohammad Sadegh; Chiniforush, Nasim

    2016-01-01

    Introduction: The aim of this study was to assess the caries-preventive potential of carbon dioxide (CO2) laser application in conjunction with the use of titanium tetra fluoride solution on the enamel adjacent to bracket. Methods: Seventy-five freshly extracted bovine incisors were used. In order to attach the brackets, the area of examination was covered with adhesive tape to limit acid etching of the entire enamel surface. Metal orthodontic brackets for upper central were bonded to all the teeth following the manufacturer’s instruction. Then all the teeth were painted with 2 layers of acid-resistant nail varnish on all surfaces except the boxes area cervical to the brackets. The teeth were then randomly divided into five groups (n = 15): control group (C); laser group (L); titanium group (T); laser-titanium group (LT) and titanium-laser group (TL). The laser-titanium group was first irradiated with CO2 laser (same as the L group) then TiF4 solution was applied on the enamel (same as the T group). Samples in the TL group were first treated with TiF4 solution (same as the T group) and then irradiated with CO2 laser on the surface (same as the L group). Then, the teeth were immersed in pH-cycling solutions. After that, the amount of calcium released into the two solutions (de- and re-mineralization) was measured with an atomic absorption spectroscopy. The data were analyzed by one-way Analysis of var-iance (ANOVA) and Tukey test. Results: Calcium loss in LT, TL and T groups were significantly lower than those in the L and C groups (P < 0.05). Conclusion: The application of Titanium tetra fluoride 4% solution on enamel can inhibit as much as 87% of subsequent caries like lesion progression. PMID:28144441

  14. COMPARISON OF CHILDREN'S FOLLOW-ON INSTANT POWDERED COW'S MILK FORMULA, BUFFALO MILK FORMULA AND CHICKEN-BASED FORMULA ON ENAMEL MICROHARDNESS OF BOVINE TEETH IN VITRO.

    PubMed

    Vongsavan, Kadkao; Rirattanapong, Praphasri; Surarit, Rudee

    2016-03-01

    Dental caries are a major public health problem worldwide. The aim of this study was to compare the effects of children's follow-on instant powdered cow's milk formula, buffalo milk formula and a chicken-based formula on microhardness of bovine enamel with artificial caries-like lesions. Forty bovine teeth were each placed in acrylic blocks and the enamel surfaces were polished to create flat 5 x 5 millimeter surfaces. The teeth surfaces were then demineralized using 0.1M lactic acid (pH 4.5) to achieve an enamel microhardness of 35-65 Vickers Hardness Numbers (VHN). All specimens were then randomly allocated into one of 4 groups (n=10/group). For remineralization, each group was soaked in a different kind of milk formula for 2 hours at 37°C except group 1 which was a negative control (artificial saliva) group. Group 2 was soaked in Murrah™ buffalo milk formula (a positive control ), group 3 in S-26-Promil-Gold™ (cow's milk formula) and group 4 in a chicken-based formula (Siriraj Hospital, Mahidol University). The microhardness of the specimens was then measured again. Data were analyzed using a one-way ANOVA and paired t-test with a 95% confidence interval. After exposure to the formula, the mean VHN for each study group was significantly higher (paired t-test, p < 0.05) except for group 1 (p = 0.345). The mean VHN for the the Murrah™ buffalo milk formula, the chicken-based formula and the S-26-Promil-Gold™ formula group were not significantly different from each other (one-way ANOVA, p > 0.05). In conclusion, S-26-Promil-Gold™ follow-on cow milk formula, Murrah™ buffalo milk formula and the chicken-based formula all increased bovine enamel microhardness after soaking for 2 hours.

  15. On dental caries and caries-related factors in children and teenagers.

    PubMed

    Alm, Anita

    2008-01-01

    Dental caries is still a common disease among children and adolescents. The aims of the present thesis were therefore: 1) to investigate the approximal caries prevalence in posterior teeth in 15-year-olds, 2) to study past caries experience in the primary dentition in relation to future caries development and need for treatment, 3) to investigate factors during early childhood which are associated with caries development later in life, and 4) to study the association between age-specific body mass index (isoBMI) and approximal caries status in 15-year-olds. Paper I has a retrospective design and the analyses were based on record data from a randomly selected sample. Papers II, III and IV are based on radiographic analyses of posterior teeth in 15-year-olds followed longitudinally from 1 to 15 years of age. The data for these studies were selected from examinations, interviews and questionnaires from early childhood and school health care records at 15 years (isoBMI values). The result showed that the approximal caries prevalence in 15-year-olds is underestimated in official caries data, since initial caries lesions are not included in these statistics. Two thirds of all 15-year-olds had approximal caries and initial caries constituted 86% of the total number of caries lesions. There was a strong relationship between caries in early childhood and approximal caries prevalence in the posterior teeth at 15 years of age. Children with caries experience at 6 years received significantly more treatment in the primary dentition during the period from 7 to 12 years compared with children who were caries free at the same age. Further, it was pointed out that parents' attitudes to dental health and psychosocial factors during early childhood have an effect on approximal caries in 15-year-olds. Additionally, plaque on primary incisors at 1 year of age and infrequent toothbrushing at 3 years of age were associated with a high caries experience at 15 years. It was also

  16. Evaluation of mineral content in healthy permanent human enamel by Raman spectroscopy

    PubMed Central

    Akkus, Asya; Roperto, Renato; Akkus, Ozan; Porto, Thiago; Teich, Sorin; Lang, Lisa

    2016-01-01

    Background An understanding of tooth enamel mineral content using a clinically viable method is essential since variations in mineralization may serve as an early precursor of a dental health issues, and may predict progression and architecture of decay in addition to assessing the success and effectiveness of the remineralization strategies. Material and Methods Twenty two human incisor teeth were obtained in compliance with the NIH guidelines and site specifically imaged with Raman microscope. The front portion of the teeth was divided into apical, medium and cervical regions and subsequently imaged with Raman microscope in these three locations. Results Measured mineralization levels have varied substantially depending on the regions. It was also observed that, the cervical enamel is the least mineralization as a populational average. Conclusions Enamel mineralization is affected by a many factors such as are poor oral hygiene, alcohol consumption and high intake of dietary carbohydrates, however the net effect manifests as overall mineral content of the enamel. Thus an early identification of the individual with overall low mineral content of the enamel may be a valuable screening tool in determining a group with much higher than average caries risk, allowing intervention before development of caries. Clinically applicable non-invasive techniques that can quantify mineral content, such as Raman analysis, would help answer whether or not mineralization is associated with caries risk. Key words:Enamel, Raman spectroscopy, mineral content, dental caries. PMID:27957268

  17. Investigation of EPR signals on tooth enamel

    NASA Astrophysics Data System (ADS)

    Pavlenko, A.; Mironova-Ulmane, N.; Polakov, M.; Riekstina, D.

    2007-12-01

    Calcified tissues are involved in continues metabolic process in human organism exchanging a number of chemical elements with environment. The rate of biochemical reactions is tissue dependent and the slowest one at the tooth enamel, the most mineralized tissue of human organism. The long time stability and unique chemical composition make tooth enamel suitable for number of application. The assessment of individual radiation dose by Electron Paramagnetic Resonance (EPR) and evaluations of elemental composition by Instrumentation Neutron Activation Analysis (INAA) are the well known procedures where properties of tooth enamel intensively used. The current work is focused on investigation of EPR signals and determination of chemical composition on several teeth samples having different origin. The EPR spectra and INAA element content of milk tooth, caries tooth, and paradantose tooth have been compared to each other. The results showed that the intensity of EPR signal is much higher for the caries tooth than the for paradantose tooth that is in agreement with depleted Ca content.

  18. Biological synthesis of tooth enamel instructed by an artificial matrix

    PubMed Central

    Huang, Z.; Newcomb, C.J.; Bringas, P.; Stupp, S.I.; Snead, M.L.

    2010-01-01

    The regenerative capability of enamel, the hardest tissue in the vertebrate body, is fundamentally limited due to cell apoptosis following maturation of the tissue. Synthetic strategies to promote enamel formation have the potential to repair damage, increase the longevity of teeth and improve the understanding of the events leading to tissue formation. Using a self-assembling bioactive matrix, we demonstrate the ability to induce ectopic formation of enamel at chosen sites adjacent to a mouse incisor cultured in vivo under the kidney capsule. The resulting material reveals the highly organized, hierarchical structure of hydroxyapatite crystallites similar to native enamel. This artificially triggered formation of organized mineral demonstrates a pathway for developing cell fabricated materials for treatment of dental caries, the most ubiquitous disease in man. Additionally, the artificial matrix provides a unique tool to probe cellular mechanisms involved in tissue formation further enabling the development of tooth organ replacements. PMID:20869764

  19. Detection of early carious lesions using contrast enhancement with coherent light scattering (speckle imaging)

    NASA Astrophysics Data System (ADS)

    Deana, A. M.; Jesus, S. H. C.; Koshoji, N. H.; Bussadori, S. K.; Oliveira, M. T.

    2013-07-01

    Currently, dental caries still represent one of the chronic diseases with the highest prevalence and present in most countries. The interaction between light and teeth (absorption, scattering and fluorescence) is intrinsically connected to the constitution of the dental tissue. Decay induced mineral loss introduces a shift in the optical properties of the affected tissue; therefore, study of these properties may produce novel techniques aimed at the early diagnosis of carious lesions. Based on the optical properties of the enamel, we demonstrate the application of first-order spatial statistics in laser speckle imaging, allowing the detection of carious lesions in their early stages. A highlight of this noninvasive, non-destructive, real time and cost effective approach is that it allows a dentist to detect a lesion even in the absence of biofilm or moisture.

  20. Early detection of dental caries using photoacoustics

    NASA Astrophysics Data System (ADS)

    Kim, K.; Witte, R.; Koh, I.; Ashkenazi, S.; O'Donnell, M.

    2006-02-01

    For decades, visual, tactile and radiographic examinations have been the standard for diagnosing caries. Nonetheless, the extent of variation in the diagnosis of dental caries is substantial among dental practitioners using these traditional techniques. Therefore, a more reliable standard for detecting incipient caries would be desirable. Using photoacoustics, near-infrared (NIR) optical contrast between sound and carious dental tissues can be relatively easily and accurately detected at ultrasound resolution. In this paper, a pulsed laser (Nd:YAG, Quanta-Ray) was used to probe extracted human molars at different disease stages determined from periapical radiographs. Both fundamental (1064nm) and first harmonic (532nm) pulses (15ns pulse length, 100mJ at fundamental and 9mJ at first harmonic , 10Hz pulse repetition rate) were used to illuminate the occlusal surface of tooth samples placed in a water tank. The photoacoustic signal was recorded with an unfocused wideband single-element piezoelectric transducer (centered at 12 MHz, bandwidth 15 MHz) positioned at small angle (less than 30 degrees) to the laser beam close to the occlusal surface. At the fundamental wavelength, total photoacoustic energy increases from normal to incipient stage disease by as much as a factor of 10. Differences between photoacoustic energy at the fundamental and first harmonic wavelength further indicate spectral absorption changes of the underlying structure with disease progression. Using a focused laser beam, an extracted molar with suspected incipient caries was scanned along the occulusal surface to help localize the caries inside enamel and dentin. The significantly increasing photoacoustic signal at a specific scan line both at fundamental and first harmonic indicates the local development of the incipient caries. The photoacoustic results compare well with visual inspection after layer by layer dissection. Preliminary results demonstrate the feasibility of detecting incipient

  1. Photodynamic therapy on bacterial reduction in dental caries: in vivo study

    NASA Astrophysics Data System (ADS)

    Baptista, Alessandra; Araujo Prates, Renato; Kato, Ilka Tiemy; Amaral, Marcello Magri; Zanardi de Freitas, Anderson; Simões Ribeiro, Martha

    2010-04-01

    The reduction of pathogenic microorganisms in supragingival plaque is one of the principal factors in caries prevention and control. A large number of microorganisms have been reported to be inactivated in vitro by photodynamic therapy (PDT). The purpose of this study was to develop a rat model to investigate the effects of PDT on bacterial reduction in induced dental caries. Twenty four rats were orally inoculated with Streptococcus mutans cells (ATCC 25175) for three consecutive days. The animals were fed with a cariogenic diet and water with 10% of sucrose ad libitum, during all experimental period. Caries lesion formation was confirmed by Optical Coherence Tomography (OCT) 5 days after the beginning of the experiment. Then, the animals were randomly divided into two groups: Control Group: twelve animals were untreated by either light or photosensitizer; and PDT Group: twelve animals were treated with 100μM of methylene blue for 5min and irradiated by a Light Emitting Diode (LED) at λ = 640+/-30nm, fluence of 172J/cm2, output power of 240mW, and exposure time of 3min. Microbiological samples were collected before, immediately after, 3, 7 and 10 days after treatment and the number of total microaerophiles was counted. OCT images showed areas of enamel demineralization on rat molars. Microbiological analysis showed a significant bacterial reduction after PDT. Furthermore, the number of total microaerophiles in PDT group remained lower than control group until 10 days posttreatment. These findings suggest that PDT could be an alternative approach to reduce bacteria in dental caries.

  2. Development of Amelogenin-chitosan Hydrogel for In Vitro Enamel Regrowth with a Dense Interface

    PubMed Central

    Ruan, Qichao; Moradian-Oldak, Janet

    2014-01-01

    Biomimetic enamel reconstruction is a significant topic in material science and dentistry as a novel approach for the treatment of dental caries or erosion. Amelogenin has been proven to be a critical protein for controlling the organized growth of apatite crystals. In this paper, we present a detailed protocol for superficial enamel reconstruction by using a novel amelogenin-chitosan hydrogel. Compared to other conventional treatments, such as topical fluoride and mouthwash, this method not only has the potential to prevent the development of dental caries but also promotes significant and durable enamel restoration. The organized enamel-like microstructure regulated by amelogenin assemblies can significantly improve the mechanical properties of etched enamel, while the dense enamel-restoration interface formed by an in situ regrowth of apatite crystals can improve the effectiveness and durability of restorations. Furthermore, chitosan hydrogel is easy to use and can suppress bacterial infection, which is the major risk factor for the occurrence of dental caries. Therefore, this biocompatible and biodegradable amelogenin-chitosan hydrogel shows promise as a biomaterial for the prevention, restoration, and treatment of defective enamel. PMID:25046057

  3. Near Infrared Imaging as a Diagnostic Tool for Detecting Enamel Demineralization: An in vivo Study

    NASA Astrophysics Data System (ADS)

    Lucas, Seth Adam

    Background and Objectives: For decades there has been an effort to develop alternative optical methods of imaging dental decay utilizing non-ionizing radiation methods. The purpose of this in-vivo study was to demonstrate whether NIR can be used as a diagnostic tool to evaluate dental caries and to compare the sensitivity and specificity of this method with that of conventional methods, including bitewing x-rays and visual inspection. Materials and Methods: 31 test subjects (n=31) from the UCSF orthodontic clinic undergoing orthodontic treatment with planned premolar extractions were recruited. Calibrated examiners performed caries detection examinations using conventional methods: bitewing radiographs and visual inspection. These findings were compared with the results from NIR examinations: transillumination and reflectance. To confirm the results found in the two different detection methods, a gold standard was used. After teeth were extracted, polarized light microscopy and transverse microradiography were performed. Results: A total of 87 premolars were used in the study. NIR identified the occlusal lesions with a sensitivity of 71% and a specificity of 77%, whereas, the visual examination had a sensitivity of only 40% and a specifity of 39%. For interproximal lesions halfway to DEJ, specificity remained constant, but sensitivity improved to 100% for NIR and 75% for x-rays. Conclusions: The results of this preliminary study demonstrate that NIR is just as effective at detecting enamel interproximal lesions as standard dental x-rays. NIR was more effective at detecting occlusal lesions than visual examination alone. NIR shows promise as an alternative diagnostic tool to the conventional methods of x-rays and visual examination and provides a non-ionizing radiation technique.

  4. The effect of casein phosphopeptide toothpaste versus fluoride toothpaste on remineralization of primary teeth enamel.

    PubMed

    Yimcharoen, Veeritta; Rirattanapong, Praphasri; Kiatchallermwong, Warawan

    2011-07-01

    This study evaluated the effect of a CPP-containing toothpaste and compared it with fluoride-containing toothpastes on remineralization of caries-like lesions in primary teeth enamel, using polarized light microscopy. Forty-eight sound primary incisors were coated with nail varnish, leaving two 1x1 mm windows before being placed in a demineralizing solution for 4 days. After demineralization, all the specimens were coated with nail varnish over one window and were randomly assigned to 4 groups (A to D; n = 12). Group A teeth were exposed to distilled water. Group B teeth were exposed to a CPP-containing toothpaste (Hi Herb). Group C teeth were exposed to a 260 ppm fluoride-containing toothpaste (Smile baby toothgel). Group D teeth were exposed to a 500 ppm fluoride-containing toothpaste (Oralmed Kid). Polarized light microscopy was used to evaluate lesion depth, before and after a 7-day pH cycle. Lesion depth was measured using a computerized method with the Image-Pro Plus program. Differences in mean lesion depth within groups and between groups were analysed using the paired t-test, Kruskal-Wallis test and Mann-Whitney U test at a 95% level of confidence. Mean lesion depths in Groups A, B, C and D significantly increased by 110.1, 36.1, 40.2 and 18.2%, respectively. The mean lesion depths for all the toothpaste groups (B, C and D) were significantly different from the control group (A). Comparisons made among treatment groups showed Group D was significantly different from Groups B and C. All toothpastes were effective for inhibiting progression of carious lesions. However, a 500 ppm fluoride-containing toothpaste inhibited lesion progression better than a CPP-containing toothpaste and a 260 ppm fluoride-containing toothpaste.

  5. The erosive susceptibility of cervical versus occlusal enamel.

    PubMed

    Hammadeh, M; Rees, J S

    2001-03-01

    Clinical studies have strongly suggested a multifactorial aetiology for abfraction lesions or non-carious cervical tooth loss, with a contribution from erosive agents. Structural studies have shown that cervical enamel is more porous with a poorly developed crystal structure that may be more prone to erosion. The aim of this study was to examine the susceptibility to erosion of cervical and occlusal enamel from human premolar and molar teeth. Small blocks of cervical and cuspal enamel were immersed in either orange juice or Coca-Cola and the surface enamel loss was measured using profilometry. The enamel loss was essentially linear at a rate of 2.2-8.8 microns/hr. It was concluded that there was little difference in the susceptibility to erosion between cervical and cuspal enamel, even when the surface hypermineralised layer was removed.

  6. Multimodal imaging system for dental caries detection

    NASA Astrophysics Data System (ADS)

    Liang, Rongguang; Wong, Victor; Marcus, Michael; Burns, Peter; McLaughlin, Paul

    2007-02-01

    Dental caries is a disease in which minerals of the tooth are dissolved by surrounding bacterial plaques. A caries process present for some time may result in a caries lesion. However, if it is detected early enough, the dentist and dental professionals can implement measures to reverse and control caries. Several optical, nonionized methods have been investigated and used to detect dental caries in early stages. However, there is not a method that can singly detect the caries process with both high sensitivity and high specificity. In this paper, we present a multimodal imaging system that combines visible reflectance, fluorescence, and Optical Coherence Tomography (OCT) imaging. This imaging system is designed to obtain one or more two-dimensional images of the tooth (reflectance and fluorescence images) and a three-dimensional OCT image providing depth and size information of the caries. The combination of two- and three-dimensional images of the tooth has the potential for highly sensitive and specific detection of dental caries.

  7. Diabetes Enhances Dental Caries and Apical Periodontitis in Caries-Susceptible WBN/KobSlc Rats

    PubMed Central

    Kodama, Yasushi; Matsuura, Masahiro; Sano, Tomoya; Nakahara, Yutaka; Ozaki, Kiyokazu; Narama, Isao; Matsuura, Tetsuro

    2011-01-01

    Many epidemiologic studies have suggested that diabetes may be an important risk factor for periodontal disease. To determine whether diabetes induces or enhances periodontal disease or dental caries, dental tissue from diabetic male and nondiabetic female WBN/KobSlc rats and male and female age-matched nondiabetic F344 rats was analyzed morphologically and morphometrically for these 2 types of lesions. Soft X-ray examination revealed that the incidence and severity of both molar caries and alveolar bone resorption were much higher in male WBN/KobSlc rats with chronic diabetes than in nondiabetic female rats of the same strain. Histopathologic examination showed that dental caries progressed from acute to subacute inflammation due to bacterial infections and necrosis in the pulp when the caries penetrated the dentin. In the most advanced stage of dental caries, inflammatory changes caused root abscess and subsequent apical periodontitis, with the formation of granulation tissue around the dental root. Inflammatory changes resulted in resorption of alveolar bone and correlated well with the severity of molar caries. Our results suggest that diabetic conditions enhance dental caries in WBN/KobSlc rats and that periodontal lesions may result from the apical periodontitis that is secondary to dental caries. PMID:21819682

  8. Tooth enamel hypoplasia in PHACE syndrome.

    PubMed

    Chiu, Yvonne E; Siegel, Dawn H; Drolet, Beth A; Hodgson, Brian D

    2014-01-01

    Individuals with PHACE syndrome (posterior fossa malformations, hemangiomas, arterial anomalies, cardiac defects, eye abnormalities, sternal cleft, and supraumbilical raphe syndrome) have reported dental abnormalities to their healthcare providers and in online forums, but dental involvement has not been comprehensively studied. A study was conducted at the third PHACE Family Conference, held in Milwaukee, Wisconsin, in July 2012. A pediatric dentist examined subjects at enrollment. Eighteen subjects were enrolled. The median age was 4.2 years (range 9 mos-9 yrs; 14 girls, 4 boys). Eleven of 18 patients had intraoral hemangiomas and five of these (50%) had hypomature enamel hypoplasia. None of the seven patients without intraoral hemangiomas had enamel hypoplasia. No other dental abnormalities were seen. Enamel hypoplasia may be a feature of PHACE syndrome when an intraoral hemangioma is present. Enamel hypoplasia increases the risk of caries, and clinicians should refer children with PHACE syndrome to a pediatric dentist by 1 year of age.

  9. Enamel craze lines.

    PubMed

    Larson, Thomas D

    2014-01-01

    Enamel craze lines are a common clinical finding, especially in older patients and in patients who brux. These craze lines frequently are discolored and may present as clear in color, grey, or brown. The clinical question is, when do enamel craze lines need restoration and when should we leave them untreated? This review will look at enamel structure and the effects of occlusion, bruxing, temperature, and restorations on enamel structure. Recommendations will be made on how and when to deal with these cosmetic defects of enamel.

  10. Increased enamel hypoplasia and very low birthweight infants.

    PubMed

    Nelson, S; Albert, J M; Geng, C; Curtan, S; Lang, K; Miadich, S; Heima, M; Malik, A; Ferretti, G; Eggertsson, H; Slayton, R L; Milgrom, P

    2013-09-01

    Birth cohort studies of developmental defects of enamel (DDE) and early childhood caries (ECC) in very low birthweight (VLBW) and normal birthweight (NBW) infants are rare. In this birth cohort of 234 VLBW and 234 NBW infants, we report the incidence of ECC and DDE at 8 and 18-20 mos of corrected age. Infant medical and maternal socio-demographic data were abstracted from medical records at birth. Dental assessments for ECC and DDE (enamel hypoplasia, demarcated and diffuse opacities) were completed at 8 and 18-20 mos. The incidence of hypoplasia was significantly higher in VLBW compared with NBW infants (8 mos, 19% vs. 2%; 18 mos, 31% vs. 8%). The incidence of ECC (International Caries Detection and Assessment System: ICDAS ≥ 2) was 1.4% (8 mos) and 12% (18-20 mos) and was similar between the VLBW and NBW groups. At both ages, using a beta-binomial regression model to control for potential confounders (maternal and infant characteristics), we found increased risk for enamel hypoplasia among the VLBW infants compared with the NBW infants. African Americans had a lower risk for enamel hypoplasia at 18-20 mos. The VLBW infants should be monitored for ECC due to the presence of enamel hypoplasia.

  11. Effect of Triphala mouthwash on the caries status

    PubMed Central

    Tandon, Shobha; Gupta, Kunal; Rao, Sugandhi; Malagi, K. J.

    2010-01-01

    Nearly 60–70% of the child Indian population suffers from dental caries. Mouth rinsing is the most cost effective method of preventing dental caries. 'Triphala' has been a classic Ayurveda remedy, probably the best known among all Ayurvedic compounds. This study was conducted on 1501 students in the age group of 8-12 years with the aim of determining the effect of Triphala mouthwash on prevention of dental caries (manifest caries) as well as incipient carious lesions, and also comparing the effect of Triphala and chlorhexidine mouthwashes. The incipient caries was recorded at 3, 6, 9 months intervals and manifest caries at 9 months interval. No significant increase in the DMFS scores was found at the end of 9 months. Also, there was no significant increase in the incipient caries score towards the conclusion of the study. It was concluded that there was no significant difference between the Triphala and the chlorhexidine mouthwashes. PMID:20814522

  12. Effect of Bioactive Primers on Bacterial-Induced Secondary Caries at the Tooth-Resin Interface.

    PubMed

    Kim, G E; Leme-Kraus, A A; Phansalkar, R; Viana, G; Wu, C; Chen, S-N; Pauli, G F; Bedran-Russo, Akb

    Secondary caries at the tooth-resin interface is the primary reason for replacement of resin composite restorations. The tooth-resin interface is formed by the interlocking of resin material with hydroxyapatite crystals in enamel and collagen mesh structure in dentin. Efforts to strengthen the tooth-resin interface have identified chemical agents with dentin collagen cross-linking potential and antimicrobial activities. The purpose of the present study was to assess protective effects of bioactive primer against secondary caries development around enamel and dentin margins of class V restorations, using an in vitro bacterial caries model. Class V composite restorations were prepared on 60 bovine teeth (n=15) with pretreatment of the cavity walls with control buffer solution, an enriched fraction of grape seed extract (e-GSE), 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide/N-hydroxysuccinimide, or chlorhexidine digluconate. After incubating specimens in a bacterial model with Streptococcus mutans for four days, dentin and enamel were assessed by fluorescence microscopy. Results revealed that only the naturally occurring product, e-GSE, significantly inhibited the development of secondary caries immediately adjacent to the dentin-resin interface, as indicated by the caries inhibition zone. No inhibitory effects were observed in enamel margins. The results suggest that the incorporation of e-GSE into components of the adhesive system may inhibit secondary caries and potentially contribute to the protection of highly vulnerable dentin-resin margins.

  13. Caries management by risk assessment: A review on current strategies for caries prevention and management

    PubMed Central

    Maheswari, S. Uma; Raja, Jacob; Kumar, Arvind; Seelan, R. Gnana

    2015-01-01

    The current trend in treating dental caries is using nondestructive risk-based caries management strategies rather than focusing on the restorative treatment alone. Currently, there have been many changes in understanding of the multifaceted nature of caries process and its management. Caries Management by Risk Assessment (CAMBRA) which is an evidence-based approach focuses on determining many factors causing the expression of disease and take corrective action. The clinicians can ascertain what behaviors are increasing a patient's risk for disease and disease progression by evaluating the current caries risk of a patient. With this modern CAMBRA protocol, a novel treatment plan can be designed to arrest dental caries thereby decreasing the chance of cavitation. After the recognition of the multi factorial nature of caries involving the biofilm, the contemporary approaches focused mainly on the various options to cope with the locally out-of-balance oral biofilm and stop the progression of the disease. The initial caries lesions can be diagnosed with modern diagnostic aids and with the help of CAMBRA, reestablishment of the integrity of the tooth surface early on in the caries process will bring great rewards for patients. This review focuses on the repair of hard tooth tissues using noninvasive strategies. PMID:26538870

  14. Amelogenin and Enamel Biomimetics

    PubMed Central

    Ruan, Qichao; Moradian-Oldak, Janet

    2015-01-01

    Mature tooth enamel is acellular and does not regenerate itself. Developing technologies that rebuild tooth enamel and preserve tooth structure is therefore of great interest. Considering the importance of amelogenin protein in dental enamel formation, its ability to control apatite mineralization in vitro, and its potential to be applied in fabrication of future bio-inspired dental material this review focuses on two major subjects: amelogenin and enamel biomimetics. We review the most recent findings on amelogenin secondary and tertiary structural properties with a focus on its interactions with different targets including other enamel proteins, apatite mineral, and phospholipids. Following a brief overview of enamel hierarchical structure and its mechanical properties we will present the state-of-the-art strategies in the biomimetic reconstruction of human enamel. PMID:26251723

  15. Chemical and crystallographic events in the caries process.

    PubMed

    LeGeros, R Z

    1990-02-01

    The chemical and crystallographic events associated with the caries process can be described based on the results from the following studies: (a) effects of carbonate, magnesium, fluoride, and strontium on the physico-chemical properties--lattice parameters, crystallinity (crystal size and strain); dissolution properties of synthetic apatites; (b) factors influencing the in vitro formation and transformation of DCPD, OCP, AP (Ca-deficient apatites), FAP, beta-TCMP (Mg-substituted), and CaF2; and (c) studies on properties (crystallinity, composition, chemical, and thermal stabilities) of enamel, dentin, and bone. The dissolution of CO3-rich/Mg-rich/F-poor dental apatite crystals and re-precipitation of CO3-poor/Mg-poor/F-rich apatite in the presence of F- ions in solution contribute to a more acid-resistant surface layer of the caries lesion. Fluoride promotes the formation of less Ca-deficient and more stable apatite crystals. The presence of Ca, P, and F in solution inhibits dissolution of apatite more than does the presence of F alone. Low levels of F in solution promote the formation of (F, OH)-apatite, even under very acid conditions; an increase in F levels causes the formation of CaF2 at the expense of DCPD or apatite, especially in acid conditions. F in apatite and/or in solution suppresses extensive dissolution of dental apatite and enhances the formation of (F, OH)-apatite crystals which are more resistant against acid-dissolution than are F-free apatite crystals.

  16. Effectiveness of chemomechanical caries removal agents Papacarie® and Carie-Care™ in primary molars: An in vitro study

    PubMed Central

    Sahana, Suzan; Vasa, Aron Arun Kumar; Geddam, Divya; Reddy, Vamsi Krishna; Nalluri, Sowjanya; Velagapudi, Nagajyothi

    2016-01-01

    Aims and Objectives: The chemomechanical caries removal system is made presently available containing a natural proteolytic enzyme for ease in the excavation of infected dentin. The aim of the study was to evaluate the efficacy and efficiency of caries removal using Papacarie® and Carie-Care™. Materials and Methods: A total of 30 extracted deciduous molars with proximal caries were collected, and each tooth was sectioned mesiodistally in the center of the carious lesion so that the two halves (buccal and lingual or palatal) have similar carious lesions, thus 30 teeth yielded 60 specimens. The specimens from each tooth were divided alternatively into two groups for caries excavation either using Papacarie® or Carie-Care™ so as to avoid selection bias. Paired t-test was used to compare mean time taken for caries removal and Fischer's exact test was done for comparing bacterial remnants after caries excavation. Results: Mean time taken for caries removal was significantly higher for Carie-Care™ (427.13 s) when compared to Papacarie® (385.8 s). Papacarie® was found to be significantly more efficient in caries removal with marked reduction in the bacterial remnants following excavation. However, both gels were found to be conservative as dentinal tubule destruction was not evident in either of them. Conclusion: Both Papacarie® and Carie-Care™ were found to be conservative in caries removal. Papacarie® was more efficient in removing bacteria in lesser time from the infected carious lesion. PMID:27195222

  17. [Dental caries of the developmental age as a civilization disease].

    PubMed

    Wójcicka, Anna; Zalewska, Magdalena; Czerech, Ewa; Jabłoński, Robert; Grabowska, Stanisława Zyta; Maciorkowska, Elzbieta

    2012-01-01

    According to the definition of the World Health Organization (WHO), dental caries is a local pathological process of the extrasomatic background, leading to enamel decalcification, decomposition of dental hard tissue, and in consequence to formation of a dental cavity. Morbidity of dental caries increases with age, reaching 100% of children, aged from 6 to 7. Poland is one of few European countries where the incidence of dental caries in children did not decrease, despite recommendations of WHO for 2000 year, aimed at the decrease in the incidence of dental caries among 6-year-old children to the level of 50%. The recommendation of WHO for 2015 year is to reduce the incidence of dental caries to 30% among 6-year-olds, i.e., 70% of 6 year-old children should be free of dental caries. Apart from genetic conditioning, inappropriate health behaviors, nutritional habits and gastroesophageal reflux disease influence the development of dental caries. Consumption of 'fast food' and drinking sweetened beverages of low pH contribute markedly to the development of dental caries, decreasing simultaneously consumption of pro healthy foods, including milk and cereals. Taking into consideration perspective clinical examinations of children and adolescents, evaluating the relationship between dental caries and nutritional habits as well as environmental conditioning, the study shows current data about factors, contributing to the incidence of dental caries in children, collected from the literature. The attention was paid to the relationship between dental caries and gastroesophageal reflux disease and the necessity of its early diagnostics and proper treatment.

  18. Optical coherence tomography use in the diagnosis of enamel defects

    NASA Astrophysics Data System (ADS)

    Al-Azri, Khalifa; Melita, Lucia N.; Strange, Adam P.; Festy, Frederic; Al-Jawad, Maisoon; Cook, Richard; Parekh, Susan; Bozec, Laurent

    2016-03-01

    Molar incisor hypomineralization (MIH) affects the permanent incisors and molars, whose undermineralized matrix is evidenced by lesions ranging from white to yellow/brown opacities to crumbling enamel lesions incapable of withstanding normal occlusal forces and function. Diagnosing the condition involves clinical and radiographic examination of these teeth, with known limitations in determining the depth extent of the enamel defects in particular. Optical coherence tomography (OCT) is an emerging hard and soft tissue imaging technique, which was investigated as a new potential diagnostic method in dentistry. A comparison between the diagnostic potential of the conventional methods and OCT was conducted. Compared to conventional imaging methods, OCT gave more information on the structure of the enamel defects as well as the depth extent of the defects into the enamel structure. Different types of enamel defects were compared, each type presenting a unique identifiable pattern when imaged using OCT. Additionally, advanced methods of OCT image analysis including backscattered light intensity profile analysis and enface reconstruction were performed. Both methods confirmed the potential of OCT in enamel defects diagnosis. In conclusion, OCT imaging enabled the identification of the type of enamel defect and the determination of the extent of the enamel defects in MIH with the advantage of being a radiation free diagnostic technique.

  19. Dental caries imaging using hyperspectral stimulated Raman scattering microscopy

    NASA Astrophysics Data System (ADS)

    Wang, Zi; Zheng, Wei; Jian, Lin; Huang, Zhiwei

    2016-03-01

    We report the development of a polarization-resolved hyperspectral stimulated Raman scattering (SRS) imaging technique based on a picosecond (ps) laser-pumped optical parametric oscillator system for label-free imaging of dental caries. In our imaging system, hyperspectral SRS images (512×512 pixels) in both fingerprint region (800-1800 cm-1) and high-wavenumber region (2800-3600 cm-1) are acquired in minutes by scanning the wavelength of OPO output, which is a thousand times faster than conventional confocal micro Raman imaging. SRS spectra variations from normal enamel to caries obtained from the hyperspectral SRS images show the loss of phosphate and carbonate in the carious region. While polarization-resolved SRS images at 959 cm-1 demonstrate that the caries has higher depolarization ratio. Our results demonstrate that the polarization resolved-hyperspectral SRS imaging technique developed allows for rapid identification of the biochemical and structural changes of dental caries.

  20. Caries diagnosis: the necessity for a new standard of care.

    PubMed

    Magid, K S

    1996-01-01

    Conclusive research has called for the elimination of the explorer as a means of diagnosing pit and fissure caries. It has been shown to be not only unreliable, but capable of spreading caries and damaging enamel. This technique, however, is still in use in most dental offices and is still taught in our dental schools. The well-intentioned placing of sealants on undiagnosed caries further exacerbates the problem. New technology has provided the means for reliably and conservatively dealing with this problem. These new modalities should become the standard in diagnosis and treatment. Video examination of all pits, fissures, and grooves for changes in light transmission, color, or staining. Microabrasion of all suspect areas at low pressure with 27 mu medical grade alpha alumina. Exposing and staining carious tooth structure with a propylene glycol caries indicator. Removal of decay using microabrasion. Restoration with a bonded composite.

  1. Amelogenin-chitosan matrix promotes assembly of an enamel-like layer with a dense interface

    PubMed Central

    Ruan, Qichao; Zhang, Yuzheng; Yang, Xiudong; Nutt, Steven; Moradian-Oldak, Janet

    2013-01-01

    Biomimetic reconstruction of tooth enamel is a significant topic of study in material science and dentistry as a novel approach for prevention, restoration, and treatment of defective enamel. We developed a new amelogenin-containing chitosan hydrogel for enamel reconstruction that works through amelogenin supramolecular assembly, stabilizing Ca-P clusters and guiding their arrangement into linear chains. These amelogenin Ca-P composite chains further fuse with enamel crystals and eventually evolve into enamel-like co-aligned crystals, anchoring to the natural enamel substrate through a cluster growth process. A dense interface between the newly-grown layer and natural enamel was formed and the enamel-like layer had improved hardness and elastic modulus compared to etched enamel. We anticipate that chitosan hydrogel will provide effective protection against secondary caries because of its pH-responsive and antimicrobial properties. Our studies introduce amelogenin-containing chitosan hydrogel as a promising biomaterial for enamel repair and demonstrate the potential of applying protein-directed assembly to biomimetic reconstruction of complex biomaterials. PMID:23571002

  2. Impact of dental caries on preschool children's quality of life: an update.

    PubMed

    Bönecker, Marcelo; Abanto, Jenny; Tello, Gustavo; Oliveira, Luciana Butini

    2012-01-01

    The literature reports that dental caries can cause functional, physical and aesthetic impairment, often with repercussions on children's general health at an early age. Moreover, recent studies have investigated how caries lesions can compromise children's quality of life. This paper aims to describe the current situation of dental caries prevalence in children and how this oral health disease can impact their quality of life.

  3. Earliest evidence of dental caries manipulation in the Late Upper Palaeolithic

    PubMed Central

    Oxilia, Gregorio; Peresani, Marco; Romandini, Matteo; Matteucci, Chiara; Spiteri, Cynthianne Debono; Henry, Amanda G.; Schulz, Dieter; Archer, Will; Crezzini, Jacopo; Boschin, Francesco; Boscato, Paolo; Jaouen, Klervia; Dogandzic, Tamara; Broglio, Alberto; Moggi-Cecchi, Jacopo; Fiorenza, Luca; Hublin, Jean-Jacques; Kullmer, Ottmar; Benazzi, Stefano

    2015-01-01

    Prehistoric dental treatments were extremely rare, and the few documented cases are known from the Neolithic, when the adoption of early farming culture caused an increase of carious lesions. Here we report the earliest evidence of dental caries intervention on a Late Upper Palaeolithic modern human specimen (Villabruna) from a burial in Northern Italy. Using Scanning Electron Microscopy we show the presence of striations deriving from the manipulation of a large occlusal carious cavity of the lower right third molar. The striations have a “V”-shaped transverse section and several parallel micro-scratches at their base, as typically displayed by cutmarks on teeth. Based on in vitro experimental replication and a complete functional reconstruction of the Villabruna dental arches, we confirm that the identified striations and the associated extensive enamel chipping on the mesial wall of the cavity were produced ante-mortem by pointed flint tools during scratching and levering activities. The Villabruna specimen is therefore the oldest known evidence of dental caries intervention, suggesting at least some knowledge of disease treatment well before the Neolithic. This study suggests that primitive forms of carious treatment in human evolution entail an adaptation of the well-known toothpicking for levering and scratching rather than drilling practices. PMID:26179739

  4. The role of fluoride mouthrinses in the control of dental caries: a brief review.

    PubMed

    Adair, S M

    1998-01-01

    Fluoride mouthrinses have generally proved to be effective in controlling caries in clinical studies. Caries reductions in North American studies have averaged about 30%. Large-scale school-based mouthrinse programs conducted during the 1970s, however, used historical controls at a time when caries rates were now known to be declining. Post-hoc analysis of the absolute (not relative) caries reductions in these studies showed that school-based fluoride mouthrinse programs were of questionable benefit from a cost standpoint. Fluoride mouthrinses have been shown to reduce demineralization and enhance remineralization of enamel adjacent to orthodontic bands and brackets. Benefits in adults have been less well documented. Use of fluoride mouthrinses by young children is discouraged until they have mastery of their swallowing reflexes. This paper recommends the use of fluoride mouthrinses for patients at increased or high risk for dental caries, but cautions that school-based programs be undertaken only in communities with a high population caries rate.

  5. Deciduous teeth occlusal caries detection with 655-nm diode laser confirmed by surface scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Duarte, Danilo; Fonseca, Yara P. C.; Zanin, Fatima A. A.; Brugnera, Aldo, Jr.

    2000-03-01

    The morphological complexity of the occlusal surface of deciduous molar teeth is considered as a factor to increase vulnerability to caries lesion. Occlusal surface of these teeth shows sulcus, pits and fissures which allow retention of both micro-organisms and food debris which make them more susceptible to caries. In the last decades there was a significant reduction on caries of smooth surface but not on the occlusal surface where dentinal caries develops under fissures which are apparently caries-free under eye observation. This is known as a hidden caries. The occlusal surface of sound extracted deciduous molar teeth were examined using a 655 nm diode laser (DIAGNOdent - KaVo) in order to detect hidden caries. When there was indication of a hidden caries, the area was examined using SEM and confirm or not the diagnosis. The authors concludes that the diagnosis of caries using 655 diode laser is reliable and precise method.

  6. [Early childhood caries--facts and prevention].

    PubMed

    Menghini, Giorgio; Steiner, Marcel; Imfeld, Thomas

    2008-02-01

    In 2003, 771 randomly selected two-year-old children from the town of Zurich were examined. Teeth with carious cavities were observed in 12.6% of the children. Caries including initial (not yet cavitated) lesions was seen in 25.3% of children. Caries prevalence was strongly associated with immigrant background. Caries was found in 7.5% of Swiss children and in 38.5% of children from ex-Jugoslavia. 5% of children of mothers born in Switzerland, and 17.4% of children of mothers not born in Switzerland showed caries. The average number of teeth with carious lesions in children with caries was 4.3 irrespective of immigrant or Swiss background. This finding suggests that all kids with caries had similar risk behaviours. Multivariate logistic regressions elucidated the behavioural components associated with caries. The presence of plaque and the use of a night-time bottle proved to be the strongest predictor variables for caries. Frequent drinking of sugared non-milk drinks, age and no pacifier use were further risk indicators in children of foreign-born mothers. A significant improvement of oral health of small children can be achieved by a concerted action of child welfare consultants, paediatricians and carers of day-nurseries. The primary goal is to convince parents to actively participate in preserving dental health of their offsprings. The following recommendations should be adhered to: 1. Parents should brush the teeth of the children daily, using a fluoridated children-toothpaste starting the very day of the appearance of the first milk tooth. 2. At the age of 12 months, the bottle should be replaced by a cup and the continuous use of a nursing bottle while falling asleep and during the night should absolutely be avoided. 3. Children should primarily be offered water and milk as a beverage. A first dental inspection is due at the age of two years.

  7. Enamel hypoplasia: challenges of esthetic restorative treatment.

    PubMed

    Ruschel, Vanessa Carla; Araújo, Élito; Bernardon, Jussara Karina; Lopes, Guilherme Carpena

    2016-01-01

    Enamel defects, such as white or yellow-brown spots, usually cause problems that are more esthetic than functional. Enamel hypoplasia may be the result of hereditary, systemic, or local factors. Dental trauma is a local etiologic factor. It is relatively common in the primary dentition and can cause defects on the surface of permanent successors. Treatment for such defects can differ, depending on the depth of the spots. For deeper white-spot lesions, a composite resin restoration may be necessary. This is an excellent mode of treatment, due to both its low cost and its conservation of healthy tooth structure. The objective of this case report is to describe composite resin restoration of a maxillary central incisor affected by enamel hypoplasia.

  8. Local study of fissure caries by Fourier transform infrared microscopy and X-ray diffraction using synchrotron radiation.

    PubMed

    Seredin, Pavel; Kashkarov, Vladimir; Lukin, Anatoliy; Ippolitov, Yury; Julian, Robert; Doyle, Stephen

    2013-09-01

    Investigations of intact dental enamel as well as carious-affected human dental enamel were performed using infrared spectromicroscopy and X-ray diffraction applying synchrotron radiation. Caries of enamel was shown to be characterized by an increase in the number of deformation and valence vibrations for N-C-O, N-H and C=O bonds, a decrease of the crystallinity index, and by the absence of the preferable orientation of hydroxyapatite crystals within the affected enamel. This indicates the presence of destructive processes in the organic matrix of hard tooth tissues.

  9. Does fluoride gel/foam application time affect enamel demineralization?

    PubMed

    Braxton, Ashanti; Garrett, Latasha; Versluis-Tantbirojn, Daranee; Versluis, Antheunis

    2014-01-01

    The American Dental Association Council on Scientific Affairs recommends a four-minute application of professionally applied topical fluoride, based on clinical evidence for caries reduction. However, some product manufacturers imply that a one-minute application is sufficient. The purpose of this laboratory study was to ascertain if a one-minute application of acidulated phosphate fluoride (APF) is equivalent to a four-minute application for reduction of enamel demineralization. We measured baseline hardness of polished bovine enamel before treatment with APF gel or foam for one or four minutes (N = 10). A control group received no fluoride treatment. The teeth were then immersed in pooled human saliva for 30 minutes, rinsed, and subjected to lactic acid gel to simulate the initial stage of dental caries. After three hours, the hardness was measured and the difference in hardness was determined as an indication of demineralization. We found that enamel hardness was significantly reduced after exposure to lactic acid gel. The reduction was significantly less in all APF-treatment groups compared to the control. However, there was no significant difference between a tooth exposed to APF gel or foam for 1 minute or for 4 minutes (ANOVA/Student-Newman-Keuls, significance level 0.05). In conclusion, APF gel and foam reduced enamel demineralization regardless of a one- or four-minute application time.

  10. Dental caries: an updated medical model of risk assessment.

    PubMed

    Kutsch, V Kim

    2014-04-01

    Dental caries is a transmissible, complex biofilm disease that creates prolonged periods of low pH in the mouth, resulting in a net mineral loss from the teeth. Historically, the disease model for dental caries consisted of mutans streptococci and Lactobacillus species, and the dental profession focused on restoring the lesions/damage from the disease by using a surgical model. The current recommendation is to implement a risk-assessment-based medical model called CAMBRA (caries management by risk assessment) to diagnose and treat dental caries. Unfortunately, many of the suggestions of CAMBRA have been overly complicated and confusing for clinicians. The risk of caries, however, is usually related to just a few common factors, and these factors result in common patterns of disease. This article examines the biofilm model of dental caries, identifies the common disease patterns, and discusses their targeted therapeutic strategies to make CAMBRA more easily adaptable for the privately practicing professional.

  11. Liquid White Enamel.

    ERIC Educational Resources Information Center

    Widmar, Marge

    1985-01-01

    A secondary teacher describes how she has her students use liquid white enamel. With the enameling process, students can create lasting, exciting artwork. They can exercise an understanding of design and color while learning the value of careful, sustained craft skills. (RM)

  12. In-vitro near-infrared imaging of natural secondary caries

    NASA Astrophysics Data System (ADS)

    Simon, Jacob C.; Lucas, Seth; Lee, Robert; Darling, Cynthia L.; Staninec, Michal; Vanderhobli, Ram; Pelzner, Roger; Fried, Daniel

    2015-02-01

    Secondary caries stands as the leading reason for the failure of composite restorations and dentists spend more time replacing existing restorations than placing new ones. Current clinical strategies, and even modern visible light methods designed to detect decay, lack the sensitivity to distinguish incipient lesions, are confounded by staining on the surface and within the tooth, or are limited to detecting decay on the tooth surface. Near-IR (NIR) imaging methods, such as NIR reflectance and transillumination imaging, and optical coherence tomography are promising strategies for imaging secondary caries. Wavelengths longer than 1300-nm avoid interference from stain and exploit the greater transparency of sound enamel and dental composites, to provide increased contrast with demineralized tissues and improved imaging depth. The purpose of this study was to determine whether NIR transillumination (λ=1300-nm) and NIR crosspolarized reflectance (λ=1500-1700-nm) images can serve as reliable indicators of demineralization surrounding composite restorations. Twelve composite margins (n=12) consisting of class I, II and V restorations were chosen from ten extracted teeth. The samples were imaged in vitro using NIR transillumination and reflectance, polarization sensitive optical coherence tomography (PS-OCT) and a high-magnification digital visible light microscope. Samples were serially sectioned into 200-μm slices for histological analysis using polarized light microscopy (PLM) and transverse microradiography (TMR). The results presented demonstrate the utility of NIR light for detecting recurrent decay and suggest that NIR images could be a reliable screening tool used in conjunction with PS-OCT for the detection and diagnosis of secondary caries.

  13. Regional Odontodysplasia with Generalised Enamel Defect

    PubMed Central

    Toumba, K. J.

    2016-01-01

    Regional odontodysplasia (ROD) is uncommon developmental anomaly, which tends to be localised and involves the ectodermal and mesodermal tooth components. A five-year-old female was referred to Department of Child Dental Health at the Leeds Dental Institute regarding malformed primary teeth. On examination 64, 74, and 72 had localised hypomineralized enamel defect. The crown of 55 was broken down with only the root remaining below the gingival level. 54 has a yellowish brown discolouration with rough irregular surface. The upper anterior teeth show mild enamel opacity. Radiographically, 55 and 54 had thin radioopaque contour, showing poor distinction between the enamel and dentine and the classic feature of a wide pulp chamber. 15, 16, and 17 were developmentally delayed and were displaying the characteristic “ghost appearance.” Comprehensive dental care was done under local anaesthesia and it included extraction of the primary molars affected by ROD, stainless steel crown on 64, and caries prevention program. Fifteen months following the initial assessment the patient's oral condition remains stable and she is under regular follow-up at the department. Paediatric dentists should be aware of this anomaly as it involves both dentitions and usually requires multidisciplinary care. PMID:28097027

  14. Color masking of developmental enamel defects: a case series.

    PubMed

    Torres, C R G; Borges, A B

    2015-01-01

    Developmental defects involving color alteration of enamel frequently compromise the esthetic appearance of the tooth. The resin infiltration technique represents an alternative treatment for color masking of these lesions and uniformization of tooth color. This technique is considered relatively simple and microinvasive, since only a minimal portion of enamel is removed. This article illustrates the color-masking effect with resin infiltration of fluorosis and traumatic hypomineralization lesions with a case series. The final esthetic outcomes demonstrated the ability of the resin infiltrant to mask the color of white developmental defect lesions, resulting in satisfactory clinical esthetic improvements. However, in more severe cases, the color-masking effect was not complete.

  15. Effect of fluoride varnish on caries prevention of partially erupted of permanent molar in high caries risk.

    PubMed

    Suwansingha, Orawan; Rirattanapong, Praphasri

    2012-05-01

    The objective of this study was to measure the effectiveness of fluoride varnish as a public health intervention to prevent caries on partially erupted first and second permanent molars among 6-11 year old children at high risk for caries. In a six-month clinical trial, 105 children were randomly divided into a fluoride varnish (Duraphat) group (117 molars) or a control group (117 molars). The chi-square test used to compare caries occurrence in each group with a 95% level of confidence (p<0.05) at the intervals of 3 months. Compared to control, fluoride varnish resulted in 79% and 77.5% caries reduction in partially erupted permanent molars at 3 and 6 months, respectively. There were statistically significant differences in caries progression between the groups at 3 and 6 months. Fluoride varnish significantly reduced carious lesions in partially erupted molars at six months among high caries risk children.

  16. Effect of Er:YAG laser on enamel demineralization around restorations.

    PubMed

    Colucci, Vivian; de Souza Gabriel, Aline Evangelista; Scatolin, Renata Siqueira; Serra, Mônica Campos; Corona, Silmara Aparecida Milori

    2015-05-01

    This study evaluates in situ the effect of erbium-doped yttrium aluminum garnet (Er:YAG) laser parameters on the development of caries-like lesions adjacent to dental restorations. One hundred fifty bovine enamel slabs were randomly allocated among 15 volunteers. The specimens were subdivided into ten groups: nine experimental groups prepared with Er:YAG laser (300 mJ output, frequency of 2, 4 or 6 Hz, water flow rate of 2.0, 5.0, or 8.0 mL/min) and one control group (high-speed handpiece). The prepared cavity was restored with a composite resin, and the slabs were mounted on palatal appliance to be installed in the volunteers to the cariogenic challenge. After this, the specimens were sectioned to the longitudinal microhardness measurements. Data were submitted to Friedman and Wilcoxon paired tests. All groups prepared with Er:YAG laser demonstrated microhardness values higher than those prepared with high-speed handpiece, which showed the lowest microhardness values (24.86). The group prepared with Er:YAG laser (2 Hz-2.0 mL/min) showed the highest microhardness values (152.43), followed by those prepared with Er:YAG laser (2 Hz-5.0 mL/min) (133.08) and Er:YAG laser (2 Hz-8.0 mL/min) (91.61), respectively. The groups Er:YAG laser with 4 and 6 Hz of frequency and water flow rates of 2.0, 5.0, and 8.0 mL/min showed microhardness values lower than the groups cited above and showed statistical similarity among them. The Er:YAG laser parameters employed to cavity preparation influenced the acid resistance of the irradiated substrate, and the Er:YAG laser was capable to control the development of caries-like lesions around composite resin restorations.

  17. Oral and dental lesions in HIV infected Nigerian children

    PubMed Central

    Oyedeji, Olusola Adetunji; Gbolahan, Olalere Omoyosola; Abe, Elizabeth Oluwatoyin; Agelebe, Efeturi

    2015-01-01

    Introduction Oral diseases in the HIV infected children though commonly encountered are under researched and often overlooked by physicians in developing countries. The aim of this study is to document the types and frequency of oral lesions in HIV infected children and examine the effects of management with HAART on their rates. Methods A cross sectional study designed to identify the oral lesions in consecutive HIV infected children and their distribution at a Paediatric Anti-retroviral clinic. Information on oral disease and clinical features of the subjects were obtained by history and clinical examination and laboratory investigations by the pediatricians and dental surgeons. Results The 58 children studied consisted of 34 boys and 24 girls with their ages ranging from 3 months to 13 years. Thirty seven (63.8%) of the 58 children had oral diseases. Enamel hypoplasia, candidiasis, caries, angular chelitis, and herpes labialis were the most common oral lesions found in the patients. Oral soft tissue lesions were less frequently encountered among children on HAART. Statistical significance was recorded among those infected with candidiasis. More than 60% of the children diagnosed with oral disease had no knowledge of the state of their oral health before the study. Conclusion Oral diseases are very common amongst the children studied. Awareness of oral disease among the children and their caregivers is low. Administration of HAART may have a preventive effect on the development of oral soft tissue disease. There is a need to integrate dental care into the paediatric HIV care programs. PMID:26161210

  18. Stereomicroscopic study of the human tooth caries: clinical and morphological correlations

    NASA Astrophysics Data System (ADS)

    Oancea, Roxana; Vasile, Liliana; Marchese, Cristian; Sava-Rosianu, Ruxandra

    2012-06-01

    Objectives: Stereomicroscopy allows a three-dimensional study of the images and of laterality at superior quality in comparison with other methods. Those advantages are given by the large examination fields and the wide work distances. The adding of the clinical and morphological data at the results gathered with stereomicroscopy and the stereo micrometry is useful in order to appreciate the deepness and the widening of the carious process, and the necessity to reconsider the therapeutically strategy. Materials and methods: During 2009-2011 the study material was represented by 10 surgically removed impacted third molars, and by 20 premolars extracted for orthodontic purposes, with closed and macroscopically apparently integer surfaces. 13 premolars with different degrees of carious affectation and periodontal lesions, which were surgically extracted without trauma, were also selected. The in situ measurements at the occlusal site were realized through the utilization of a fluorescent laser device - DIAGNOdent. The basic principles in stereomicroscopy stood at the base of the obliquely and circularly coaxial illumination techniques, one with optical alignment adjustment of the optical microscope and mechanical adjustment for the optimal illumination and micrometry. The Olympus Microscope SZ ×7 and an Olympus camera with 2,5 × digital zoom and a 3× optical zoom has been used to study the samples in stereomicroscopy and through polarized light it. Results: The DiagnoDent measured the following data: out of 43 apparently healthy teeth, 18 presented values between 2 and 13 (D1), 13 showed values between 14 and 24 (D2), 12 measured values over 24 (D3). After the histological examination in stereomicroscopy and in the polarized light: 25 teeth were healthy, 10 presented caries extended in dental enamel and 8 presented dentinal caries. Stereomicroscopy has allowed the morphological study, the color absorption, the appreciation of the lesions' deepness and substance

  19. Caries Risk Assessment/Treatment Programs in U.S. Dental Schools.

    ERIC Educational Resources Information Center

    Yorty, Jack S.; Brown, K. Birgitta

    1999-01-01

    A survey of 42 U.S. dental schools was conducted to identify the number and characteristics of caries risk- assessment/treatment programs. Findings address lectures about caries risk, use of variable recall programs, categorization of risk level, early detection and treatment of lesions, and restoration of radiographically visible lesions. (DB)

  20. Diet and the microbial aetiology of dental caries: new paradigms.

    PubMed

    Bradshaw, David J; Lynch, Richard J M

    2013-12-01

    The microbial and dietary factors that drive caries have been studied scientifically for 120 years. Frequent and/or excessive sugar (especially sucrose) consumption has been ascribed a central role in caries causation, while Streptococcus mutans appeared to play the key role in metabolising sucrose to produce lactic acid, which can demineralise enamel. Many authors described caries as a transmissible infectious disease. However, more recent data have shifted these paradigms. Streptococcus mutans does not fulfil Koch's postulates - presence of the organism leading to disease, and absence of the organism precluding disease. Furthermore, molecular microbiological methods have shown that, even with a sugar-rich diet, a much broader spectrum of acidogenic microbes is found in dental plaque. While simple sugars can be cariogenic, cooked starches are also now recognised to be a caries threat, especially because such starches, while not 'sticky in the hand', can be highly retentive in the mouth. Metabolism of starch particles can yield a prolonged acidic challenge, especially at retentive, caries-prone sites. These changes in the paradigms of caries aetiology have important implications for caries control strategies. Preventing the transmission of S. mutans will likely be inadequate to prevent caries if a sufficiently carbohydrate-rich diet continues. Similarly, restriction of sucrose intake, although welcome, would be unlikely to be a panacea for caries, especially if frequent starch intake persisted. Instead, approaches to optimise fluoride delivery, to target plaque acidogenicity or acidogenic microbes, to promote plaque alkali generation, to increase salivary flow or replace fermentable carbohydrates with non-fermentable alternatives may be more promising.

  1. Caries Management Strategies for Primary Molars

    PubMed Central

    Santamaria, R.M.; Innes, N.P.T.; Machiulskiene, V.; Evans, D.J.P.; Splieth, C.H.

    2014-01-01

    Minimal invasive approaches to managing caries, such as partial caries removal techniques, are showing increasing evidence of improved outcomes over the conventional complete caries removal. There is also increasing interest in techniques where no caries is removed. We present the 1-yr results of clinical efficacy for 3 caries management options for occlusoproximal cavitated lesions in primary molars: conventional restorations (CR; complete caries removal and compomer restoration), Hall technique (HT; no caries removal, sealing in with stainless steel crowns), and nonrestorative caries treatment (NRCT; no caries removal, opening up the cavity, teaching brushing and fluoride application). In sum, 169 children (3-8 yr old; mean, 5.56 ± 1.45 yr) were enrolled in this secondary care–based, 3-arm, parallel-group, randomized clinical trial. Treatments were carried out by specialist pediatric dentists or postgraduate trainees. One lesion per child received CR, HT, or NRCT. Outcome measures were clinical failure rates, grouped as minor failure (restoration loss/need for replacement, reversible pulpitis, caries progression, etc.) and major failure (irreversible pulpitis, abscess, etc.). There were 148 children (87.6%) with a minimum follow-up of 11 mo (mean, 12.23 ± 0.98 mo). Twenty teeth were recorded as having at least 1 minor failure: NRCT, n = 8 (5%); CR, n = 11 (7%); HT, n = 1 (1%) (p = .002, 95% CI = 0.001 to 0.003). Only the comparison between NRCT and CR showed no significant difference (p = .79, 95% CI = 0.78 to 0.80). Nine (6%) experienced at least 1 major failure: NRCT, n = 4 (2%); CR, n = 5 (3%); HT, n = 0 (0%) (p = .002, 95% CI = 0.001 to 0.003). Individual comparison of NRCT and CR showed no statistically significant difference in major failures (p = .75, 95% CI = 0.73 to 0.76). Success and failure rates were not significantly affected by pediatric dentists’ level of experience (p = .13, 95% CI = 0.12 to 0.14). The HT was significantly more successful

  2. Magnesium and carbonate in enamel and synthetic apatites.

    PubMed

    LeGeros, R Z; Sakae, T; Bautista, C; Retino, M; LeGeros, J P

    1996-11-01

    This study aimed to: determine the Mg and CO3 distribution in the outer (surface), middle, and inner (closest to the enamel-dentin junction, EDJ) layers of human enamel; and determine the factors affecting the incorporation of Mg into synthetic apatites and the consequence of such incorporation on the properties of the apatites. Results demonstrated that the concentrations of Mg, CO3, and organic components increased from the surface to the inner layers close to the EDJ and a difference in crystallinity from the outer to the inner layers. Initial results indicated that the extent of dissolution of the inner layer enamel is greater than that in the outer or surface enamel. Results on synthetic apatites showed the following: (1) Limited Mg incorporation into apatite was dependent on solution [Mg/Ca] molar ratio, temperature, pH, and the presence of CO3 or fluoride (F); (2) incorporation of Mg causes reduction in crystallinity and an increase in the extent of dissolution of the apatite; (3) the negative effect of Mg on the properties of apatites is synergistic to that of CO3 and antagonistic to that of F; and (4) exposure to acid of Mg-containing apatites causes the dissolution of Mg-rich apatite and precipitation of Mg-poor apatite. The observed decrease in the [Mg/Ca] of enamel and synthetic apatites after acid exposure may explain the observed 'preferential loss' of Mg and CO3 in the initial stages of caries.

  3. Candida albicans in oral biofilms could prevent caries.

    PubMed

    Willems, Hubertine Marjoleine; Kos, Kevin; Jabra-Rizk, Mary Ann; Krom, Bastiaan P

    2016-07-01

    Streptococcus mutans is a Gram-positive bacterium involved in development to caries, the most common infectious disease of our time. Streptococcus mutans interacts with other microbes, like the fungus Candida albicans and both are commonly isolated from patients with caries. Since the role of C. albicans in caries remains unknown, our aim was to unravel this using an in vitro dual-species cariogenic oral biofilm model. Biofilms were grown for 24-72 h on glass cover slips or hydroxyapatite (HA) disks to mimic the surface of teeth. Medium pH, lactic acid production capacity and calcium release from HA disks were determined. All 24-h biofilms had external pH values below the critical pH of 5.5 where enamel dissolves. In contrast, 72-h dual-species biofilms had significantly higher pH (above the critical pH) and consequently decreased calcium release compared to single-species S. mutans biofilms. Counter intuitively, lactic acid production and growth of S. mutans were increased in 72-h dual-species biofilms. Candida albicans modulates the pH in dual-species biofilms to values above the critical pH where enamel dissolves. Our results suggest that C. albicans is not by definition a cariogenic microorganism; it could prevent caries by actively increasing pH preventing mineral loss.

  4. Protein- mediated enamel mineralization

    PubMed Central

    Moradian-Oldak, Janet

    2012-01-01

    Enamel is a hard nanocomposite bioceramic with significant resilience that protects the mammalian tooth from external physical and chemical damages. The remarkable mechanical properties of enamel are associated with its hierarchical structural organization and its thorough connection with underlying dentin. This dynamic mineralizing system offers scientists a wealth of information that allows the study of basic principals of organic matrix-mediated biomineralization and can potentially be utilized in the fields of material science and engineering for development and design of biomimetic materials. This chapter will provide a brief overview of enamel hierarchical structure and properties as well as the process and stages of amelogenesis. Particular emphasis is given to current knowledge of extracellular matrix protein and proteinases, and the structural chemistry of the matrix components and their putative functions. The chapter will conclude by discussing the potential of enamel for regrowth. PMID:22652761

  5. Current status of dental caries diagnosis using cone beam computed tomography

    PubMed Central

    Park, Young-Seok; Ahn, Jin-Soo; Kwon, Ho-Beom

    2011-01-01

    Purpose The purpose of this article is to review the current status of dental caries diagnosis using cone beam computed tomography (CBCT). Materials and Methods An online PubMed search was performed to identify studies on caries research using CBCT. Results Despite its usefulness, there were inherent limitations in the detection of caries lesions through conventional radiograph mainly due to the two-dimensional (2D) representation of caries lesions. Several efforts were made to investigate the three-dimensional (3D) image of lesion, only to gain little popularity. Recently, CBCT was introduced and has been used for diagnosis of caries in several reports. Some of them maintained the superiority of CBCT systems, however it is still under controversies. Conclusion The CBCT systems are promising, however they should not be considered as a primary choice of caries diagnosis in everyday practice yet. Further studies under more standardized condition should be performed in the near future. PMID:21977474

  6. Assessment of remineralized dentin lesions with thermal and near-infrared reflectance imaging

    NASA Astrophysics Data System (ADS)

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2016-02-01

    Accurate detection and measurement of the highly mineralized surface layer that forms on caries lesions is important for the diagnosis of lesion activity. Previous studies have demonstrated that optical imaging methods can be used to measure the degree of remineralization on enamel lesions. The purpose of this study was to determine if thermal and near-IR reflectance imaging could be used to assess the remineralization process in simulated dentin lesions. Artificial bovine (n=15) dentin lesions were prepared by immersion in a demineralization solution for 24 hours and they were subsequently placed in an acidic remineralization solution for up to 12 days. The samples were dehydrated using an air spray for 30 seconds and imaged using thermal and InGaAs cameras. The area enclosed by the time-temperature curve, ΔQ, from thermal imaging decreased significantly with longer periods of remineralization. However, near-IR reflectance intensity differences, ΔI, before and after dehydration failed to show any significant relationship with the degree of remineralization. This study shows that thermal imaging can be used for the assessment of the remineralization of dentin lesions.

  7. Assessment of remineralized dentin lesions with thermal and near-infrared reflectance imaging

    PubMed Central

    Lee, Robert C.; Darling, Cynthia L.; Fried, Daniel

    2016-01-01

    Accurate detection and measurement of the highly mineralized surface layer that forms on caries lesions is important for the diagnosis of lesion activity. Previous studies have demonstrated that optical imaging methods can be used to measure the degree of remineralization on enamel lesions. The purpose of this study was to determine if thermal and near-IR reflectance imaging could be used to assess the remineralization process in simulated dentin lesions. Artificial bovine (n=15) dentin lesions were prepared by immersion in a demineralization solution for 24 hours and they were subsequently placed in an acidic remineralization solution for up to 12 days. The samples were dehydrated using an air spray for 30 seconds and imaged using thermal and InGaAs cameras. The area enclosed by the time-temperature curve, ΔQ, from thermal imaging decreased significantly with longer periods of remineralization. However, near-IR reflectance intensity differences, ΔI, before and after dehydration failed to show any significant relationship with the degree of remineralization. This study shows that thermal imaging can be used for the assessment of the remineralization of dentin lesions. PMID:27006522

  8. Effect of caries in mentally handicapped children of addition of fluoride and bicarbonate-phosphate to dietary sugar products.

    PubMed

    Luoma, H; Nyman, A; Toivonen, A; Söderholm, S; Nuuja, T; Kantero, R L; Hassinen, M L; Jokela, M; Nummikoski, P; Ranta, H; Thesleff, I

    1979-06-01

    Mentally handicapped children, aged 5--15 years and living in institutions, received fluoride supplement in several sugar products of their diet; in candies, marmalades, jams, fruit juices and in sweet desserts corresponding to 10 mg F as NaF per kg of the sugar (sucrose or glucose) of each product. To two of the four daily candies was also added a NaHCO3 + KH2PO4 mixture (mole ratio 9.8/l, resp.) to substitute for 2.5% of the sugar of the candy. The control children received the respective products without the additives. After stepwise exclusions of subjects for various reasons, e.g. for the absence of permanent teeth, low initial caries activity, strong medication, Down's syndrome, etc., the mean DMFS-increment in the remaining 43 control subjects was 4.5 and in the 41 test subjects 2.6 lesions/100 surfaces at risk, i.e. 42% reduction. Caries arrestment had occurred in these test subjects after the first year, while in the respective controls it was continuously increasing. Among numerous oral and body parameters studied, only surface enamel fluoride in primary teeth was increased by the fluoride supplements and urinary phosphate and calcium excretion decreased.

  9. Developmental defects of enamel and dentine: challenges for basic science research and clinical management.

    PubMed

    Seow, W K

    2014-06-01

    Abnormalities of enamel and dentine are caused by a variety of interacting factors ranging from genetic defects to environmental insults. The genetic changes associated with some types of enamel and dentine defects have been mapped, and many environmental influences, including medical illnesses that can damage enamel and dentine have been identified. Developmental enamel defects may present as enamel hypoplasia or hypomineralization while dentine defects frequently demonstrate aberrant calcifications and abnormalities of the dentine-pulp complex. Clinically, developmental enamel defects often present with problems of discolouration and aesthetics, tooth sensitivity, and susceptibility to caries, wear and erosion. In contrast, dentine defects are a risk for endodontic complications resulting from dentine hypomineralization and pulpal abnormalities. The main goals of managing developmental abnormalities of enamel and dentine are early diagnosis and improvement of appearance and function by preserving the dentition and preventing complications. However, despite major advances in scientific knowledge regarding the causes of enamel and dentine defects, further research is required in order to translate the knowledge gained in the basic sciences research to accurate clinical diagnosis and successful treatment of the defects.

  10. No Carious Cervical Lesions: Abfraction

    PubMed Central

    Shetty, Sumanth M; Shetty, Rashmi G; Mattigatti, Sudha; Managoli, Noopur A; Rairam, Surabhi G; Patil, Ashwini M

    2013-01-01

    Abfraction or Theory of Abfraction is a theory explaining the non-carious cervical lesions (NCCL). It suggests that they are caused by flexural forces, usually from cyclic loading; the enamel, especially at the cementoenamel junction (CEJ), undergoes this pattern of destruction by separating the enamel rods. Clinical aspect importance of these ineart lesions are at most important to be detected for early intervention and treatment modalities as options during the progression of the disease. How to cite this article: Shetty SM, Shetty RG, Mattigatti S, Managoli NA, Rairam SG, Patil AM. No Carious Cervical Lesions: Abfraction. J Int Oral Health 2013; 5(5):142-5. PMID:24324319

  11. No carious cervical lesions: abfraction.

    PubMed

    Shetty, Sumanth M; Shetty, Rashmi G; Mattigatti, Sudha; Managoli, Noopur A; Rairam, Surabhi G; Patil, Ashwini M

    2013-10-01

    Abfraction or Theory of Abfraction is a theory explaining the non-carious cervical lesions (NCCL). It suggests that they are caused by flexural forces, usually from cyclic loading; the enamel, especially at the cementoenamel junction (CEJ), undergoes this pattern of destruction by separating the enamel rods. Clinical aspect importance of these ineart lesions are at most important to be detected for early intervention and treatment modalities as options during the progression of the disease. How to cite this article: Shetty SM, Shetty RG, Mattigatti S, Managoli NA, Rairam SG, Patil AM. No Carious Cervical Lesions: Abfraction. J Int Oral Health 2013; 5(5):142-5.

  12. Treatment modalities for caries management, including a new resin infiltration system.

    PubMed

    Kugel, Gerard; Arsenault, Peter; Papas, Athena

    2009-10-01

    Seemingly against all odds, dental caries still affects most people in the US. While fluoridated products, school-based screening and cleaning programs, better patient education, and professional and chemotherapeutic interventions have all impacted certain populations, caries is still the most prevalent chronic childhood disease and continues to affect a high percentage of adolescents, young and middle-aged adults, and seniors. Much research has proven that dental caries is not just an occasional cycle of cavitation but a complex and infectious disease process. Historically, addressing the caries challenge has relied on prevention and restoration, with no intermediary means to stop lesion progression. Recently, a technique called caries infiltration was introduced that fills the noncavitated pores of an incipient lesion with a low-viscosity resin by capillary action, creating a barrier that blocks further bacterial diffusion and lesion development. This microinvasive method for stabilizing early lesions requires no drilling or anesthesia and does not alter the tooth's anatomic shape. In cases of white spot lesions in the esthetic zone, it also eliminates opaqueness and blends with surrounding natural teeth. This article presents an overview of caries prevention initiatives and a case demonstrating the new caries infiltration technique. Combined with shifting the focus to caries risk assessment, this promising technology may prove to be a significant addition to the profession's caries treatment armamentarium.

  13. Genetic Variation in Ameloblastin Is Associated with Caries in Asthmatic Children

    PubMed Central

    Ergöz, Nihan; Seymen, Figen; Gencay, Koray; Tamay, Zeynep; Deeley, Kathleen; Vinski, Sarah; Vieira, Alexandre R.

    2014-01-01

    Aim Evidence suggests caries experience is higher in children with asthma. In this study, we compared caries experience in asthmatic and non-asthmatic children and defined whether variation in the distribution of caries experience differs between the two groups and is dependent of the presence of genetic variation in enamel formation genes. Methods Children with asthma were recruited at the Istanbul University, Faculty of Medicine, Department of Pediatrics, Division of Pediatric Allergy and Pulmonary Diseases, and non-affected children were recruited at the Istanbul University, Faculty of Dentistry, Department of Pedodontics. Cases (N=100) were defined as children between the ages of 6 and 12 years with asthma and controls (N=100) as children without asthma. Cases and controls were matched by sex and age. All study subjects received a complete dental exam, provided demographic and other caries and asthma risk factors data, and a saliva sample for DNA extraction. Caries experience was defined based on DMFT/dmft and DMFS/dmfs scores. Genotypes of 11 SNPs were selected in intronic regions of enamel development genes. PCR with TaqMan chemistry were used for genotyping all selected markers. Association between caries experience (caries free versus caries affected) depending on asthma status and SNPs was tested with PLINK by logistic regression, adjusting by risk, and other preventive measures. P-values below 0.0045 (0.05/11) were considered statistically significant. Results Logistic regression analysis showed an association between AMBN rs4694075 and caries experience (p=2.525e-007). Conclusions Our study provides, for the first time, evidence that ameloblastin is associated with caries in asthmatic children. PMID:24203249

  14. A simple model for the effect of flouride ions on remineralization of partly demineralized tooth enamel

    NASA Astrophysics Data System (ADS)

    Christoffersen, J.; Christoffersen, M. R.; Arends, J.

    1984-06-01

    A model is presented for remineralization of partly demineralized tooth enamel, taking the effect of the presence of fluoride ions into account. The model predicts that, in the absence of precipitation of other phases than calcium hydroxyapatite (HAP) and fluroridized HAP, which are assumed to model enamel, there exists a maximum value of the fluoride concentration gradient, above which lesions cannot be successfully repaired.

  15. Development of fluorapatite cement for dental enamel defects repair.

    PubMed

    Wei, Jie; Wang, Jiecheng; Shan, Wenpeng; Liu, Xiaochen; Ma, Jian; Liu, Changsheng; Fang, Jing; Wei, Shicheng

    2011-06-01

    In order to restore the badly carious lesion of human dental enamel, a crystalline paste of fluoride substituted apatite cement was synthesized by using the mixture of tetracalcium phosphate (TTCP), dicalcium phosphate anhydrous (DCPA) and ammonium fluoride. The apatite cement paste could be directly filled into the enamel defects (cavities) to repair damaged dental enamel. The results indicated that the hardened cement was fluorapatite [Ca(10)(PO(4))(6)F(2), FA] with calcium to phosphorus atom molar ratio (Ca/P) of 1.67 and Ca/F ratio of 5. The solubility of FA cement in Tris-HCl solution (pH = 5) was slightly lower than the natural enamel, indicating the FA cement was much insensitive to the weakly acidic solutions. The FA cement was tightly combined with the enamel surface, and there was no obvious difference of the hardness between the FA cement and natural enamel. The extracts of FA cement caused no cytotoxicity on L929 cells, which satisfied the relevant criterion on dental biomaterials, revealing good cytocompatibility. In addition, the results showed that the FA cement had good mechanical strength, hydrophilicity, and anti-bacterial adhesion properties. The study suggested that using FA cement was simple and promising approach to effectively and conveniently restore enamel defects.

  16. Cary Woods Elementary School.

    ERIC Educational Resources Information Center

    Havens, Glenda

    1994-01-01

    Describes the school reading program at Cary Woods Elementary School (in Auburn, Alabama), one of several school reading programs designated by the International Reading Association as exemplary. (SR)

  17. Effects of Treatment with Various Remineralizing Agents on the Microhardness of Demineralized Enamel Surface.

    PubMed

    Salehzadeh Esfahani, Kiana; Mazaheri, Romina; Pishevar, Leila

    2015-01-01

    Background and aims. Remineralization of incipient caries is one of the goals in dental health care. The present study aimed at comparing the effects of casein phosphopeptide-amorphous calcium phosphate complex (CPP-ACP), Remin Pro(®), and 5% sodium fluoride varnish on remineralization of enamel lesions. Materials and methods. In this in vitro study, 60 enamel samples were randomly allocated to six groups of 10. After four days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 underwent one-time treatment with fluoride varnish, CPP-ACP, and Remin Pro(®), respectively. Microhardness of groups 4-6 was measured not only after one-month treatment with the above-mentioned materials (for eight hours a day), but also after re-exposing to the demineralizing solution. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Fisher's least significant difference (LSD) test. Results . None of the regimens could increase microhardness in groups 1-3. However, one-month treatment regimens in groups 4-6 caused a significant increase in microhardness. The greatest microhardness was detected in the group treated with CPP-ACP (P = 0.001). In addition, although microhardness reduced following re-demineralization in all three groups, the mean reduction was minimum in the CPP-ACP-treated group (P < 0.001). Conclusion. While long-term repeated application of all compounds improved microhardness, the remineralization potential of CPP-ACP was significantly higher than that of Remin Pro(®) and sodium fluoride varnish.

  18. Effects of Treatment with Various Remineralizing Agents on the Microhardness of Demineralized Enamel Surface

    PubMed Central

    Salehzadeh Esfahani, Kiana; Mazaheri, Romina; Pishevar, Leila

    2015-01-01

    Background and aims. Remineralization of incipient caries is one of the goals in dental health care. The present study aimed at comparing the effects of casein phosphopeptide-amorphous calcium phosphate complex (CPP-ACP), Remin Pro®, and 5% sodium fluoride varnish on remineralization of enamel lesions. Materials and methods. In this in vitro study, 60 enamel samples were randomly allocated to six groups of 10. After four days of immersion in demineralizing solution, microhardness of all samples was measured. Afterward, groups 1-3 underwent one-time treatment with fluoride varnish, CPP-ACP, and Remin Pro®, respectively. Microhardness of groups 4-6 was measured not only after one-month treatment with the above-mentioned materials (for eight hours a day), but also after re-exposing to the demineralizing solution. The results were analyzed by one-way analysis of variance (ANOVA), repeated measures ANOVA, and Fisher’s least significant difference (LSD) test. Results. None of the regimens could increase microhardness in groups 1-3. However, one-month treatment regimens in groups 4-6 caused a significant increase in microhardness. The greatest microhardness was detected in the group treated with CPP-ACP (P = 0.001). In addition, although microhardness reduced following re-demineralization in all three groups, the mean reduction was minimum in the CPP-ACP-treated group (P < 0.001). Conclusion. While long-term repeated application of all compounds improved microhardness, the remineralization potential of CPP-ACP was significantly higher than that of Remin Pro® and sodium fluoride varnish. PMID:26889361

  19. Incidence of dental caries in primary dentition and risk factors: a longitudinal study.

    PubMed

    Corrêa-Faria, Patrícia; Paixão-Gonçalves, Suzane; Paiva, Saul Martins; Pordeus, Isabela Almeida

    2016-05-20

    The objectives of this prospective, longitudinal, population-based study were to estimate the incidence of dental caries in the primary dentition, identify risk factors and determine the proportion of children receiving dental treatment, through a two-year follow up. The first dental exam was conducted with 381 children aged one to five years, at health centers during immunization campaigns; 184 of them had dental caries and 197 had no caries experience. The second exam was carried out two years later at a nursery or at home with the same individuals who participated in the first exam. The diagnosis of dental caries was performed using the dmft criteria. Parents were interviewed regarding socioeconomic indicators. Descriptive, bivariate and adjusted Poisson regression analyses were performed. Among the 381 children, 234 were reexamined after two years (non-exposed: 139; exposed: 95). The overall incidence of dental caries was 46.6%. The greatest incidence of dental caries was found in the group of children with previous caries experience (61.1%). Among the children without dental caries in the first exam, 36.7% exhibited caries in the second exam. The majority of children (72.6%) received no treatment for carious lesions in the two-year interval between examinations. Children with previous dental caries (RR: 1.52, 95%CI: 1.12-2.05) had a greater risk of developing new lesions, compared with the children without previous dental caries. The incidence of dental caries was high and most of children's caries were untreated. Previous caries experience is a risk factor for developing new carious lesions in children.

  20. Dental caries: A complete changeover, PART III: Changeover in the treatment decisions and treatments

    PubMed Central

    Carounanidy, Usha; Sathyanarayanan, R

    2010-01-01

    Comprehensive management of dental caries should involve the management of disease as well as the lesion. Current decision making process in cariology is influenced by numerous factors such as the size/ depth/ activity of the carious lesion and age/ the caries risk status of the patient. Treatment decisions should involve planning the non-operative/ preventive treatment for non-cavitated or early cavitated lesions and also formulating operative treatment for cavitated lesions. Apart from these two responsibilities, a clinician should also be knowledgeable enough to decide when not to interfere in the caries dynamics and how frequently to recall the patient for follow-ups. The non-operative treatment prescriptions vary in dose, intensity and mode of delivery according to the caries risk status. Minimal invasion and maximal conservation of tooth structure has become the essence of current operative treatments. This part of the series elaborates on the paradigm shift in the management of dental caries. PMID:21217948

  1. Effect of carbon dioxide laser treatment on lesion progression in an intraoral model

    NASA Astrophysics Data System (ADS)

    Featherstone, John D. B.; Fried, Daniel; Gansky, Stuart A.; Stookey, George K.; Dunipace, Ann J.

    2001-04-01

    Previous studies have shown that pretreatment of dental enamel by specific carbon dioxide laser conditions inhibited subsequent progression of caries-like lesions in vitro. The aim of the present study was to use an intra-oral model to determine whether similar inhibition is observed in the human mouth. A cross over study with 23 subjects and three regimens was used. Pre-formed varies-like lesions were made in extracted human enamel and exposed intra-orally in partial dentures in each subject to A) placebo dentifrice and no laser treatment, B) placebo dentifrice following laser pretreatment, or C) sodium fluoride dentifrice and no laser treatment during each of three study periods. Samples were assessed by micro radiography to compare the mineral loss before and after each treatment and drive a net change in mineral value. Overall P was not significantly different form L but both P and L were different from F. For those subjects who demineralized in P, L and F were significantly better than P, with L showing an 84 percent inhibition of further demineralization, but no enhancement of demineralization.

  2. Crystalline structure of dental enamel after Ho:YLF laser irradiation.

    PubMed

    Bachmann, Luciano; Craievich, Aldo Felix; Zezell, Denise Maria

    2004-11-01

    Irradiation of teeth with lasers using specific wavelengths and energy densities produces surface melting. This effect has been already applied to different procedures such as caries prevention and hypersensitivity reduction. The aim of this study is to characterize the crystalline structure of bovine enamel after holmium laser irradiation. A holmium laser (Ho:YLF) with emission wavelength of 2065 nm was used. Enamel tissues were irradiated in ablative regime and their structures before and after irradiation were analyzed using the powder X-ray diffraction technique. The X-ray diffraction patterns of non-irradiated enamel correspond to carbonated hydroxyapatite and those produced by irradiated samples indicate the existence of a mixture of two crystalline phases: hydroxyapatite and tetracalcium phosphate. The structural characteristics of holmium irradiated enamel were compared with those of the same tissue irradiated with other lasers.

  3. Effect of resin infiltration on the nanomechanical properties of demineralized bovine enamel

    PubMed Central

    Tostes, Mônica Almeida; Santos, Emanuel; Camargo, Sérgio Alvaro

    2014-01-01

    Objective: The aim of the present study was to evaluate the efficacy of resin infiltration in preventing in vitro lesion progression. Materials and Methods: Buccal surfaces of bovine incisors were divided into mesial and distal regions and, at the center, nail varnish was applied (1.0 mm width) to protect the enamel surface against any further treatment. In order to create artificial enamel lesions in the unprotected areas, each specimen was soaked in a demineralizing solution. After that, specimens had two enamel lesions. One lesion in each sample was etched with 15% HCl for 120 s and infiltrated with a commercial infiltrating resin for 3 min, while the other lesion was not treated (control). Each specimen was cross-sectionally halved and randomly allocated to two groups: Group 1 was immediately processed and Group 2 was submitted to a new demineralization process. The samples were analyzed by means of cross-sectional hardness measurements using a nanoindenter equipment. Hardness data were statistically analyzed by non-parametric Kruskal-Wallis and MannWhitney tests (α = 0.05). Results: The findings showed statistical difference between treatments at the same analyzed distance range from the outer surface of the enamel (P < 0.05). Conclusion: The untreated lesion showed lower hardness values for distances near the outer surface of the enamel. The resin infiltration was efficient in preventing further in vitro demineralization of bovine enamel lesions. PMID:25565739

  4. Does ozone enhance the remineralizing potential of nanohydroxyapatite on artificially demineralized enamel? A laser induced fluorescence study

    NASA Astrophysics Data System (ADS)

    Srinivasan, Samuelraj; Prabhu, Vijendra; Chandra, Subhash; Koshy, Shalini; Acharya, Shashidhar; Mahato, Krishna K.

    2014-02-01

    The present era of minimal invasive dentistry emphasizes the early detection and remineralization of initial enamel caries. Ozone has been shown to reverse the initial demineralization before the integrity of the enamel surface is lost. Nano-hydroxyapatite is a proven remineralizing agent for early enamel caries. In the present study, the effect of ozone in enhancing the remineralizing potential of nano-hydroxyapatite on artificially demineralized enamel was investigated using laser induced fluorescence. Thirty five sound human premolars were collected from healthy subjects undergoing orthodontic treatment. Fluorescence was recorded by exciting the mesial surfaces using 325 nm He-Cd laser with 2 mW power. Tooth specimens were subjected to demineralization to create initial enamel caries. Following which the specimens were divided into three groups, i.e ozone (ozonated water for 2 min), without ozone and artificial saliva. Remineralization regimen was followed for 3 weeks. The fluorescence spectra of the specimens were recorded from all the three experimental groups at baseline, after demineralization and remineralization. The average spectrum for each experimental group was used for statistical analysis. Fluorescence intensities of Ozone treated specimens following remineralization were higher than that of artificial saliva, and this difference was found to be statistically significant (P<0.0001). In a nutshell, ozone enhanced the remineralizing potential of nanohydroxyapatite, and laser induced fluorescence was found to be effective in assessing the surface mineral changes in enamel. Ozone can be considered an effective agent in reversing the initial enamel caries there by preventing the tooth from entering into the repetitive restorative cycle.

  5. Effect of chlorhexidine gel on approximal caries increment in adolescents with high caries risk using professional flossing compared to individual trays.

    PubMed

    Lindquist, Birgitta; Gisselsson, Hans; Wennerholm, Kerstin

    2010-01-01

    The aim of this study was to evaluate the effect of chlorhexidine gel treatment on approximal caries development during a three year-study in children with expected high risk of caries. New caries of this group was compared to the caries development in two groups with assumed moderate or low caries risk. One hundred and sixty-nine of 201 twelve-year-old children fulfilled the trial. A group of 77 children showed no caries experience and was expected to be a low caries risk group (R1). Ninety-two children had at least one approximal lesion and their salivary numbers of mutans streptococci (ms) were quantified. Forty-six of those showed less than 3 x 10(5) ms per ml saliva and were supposed to have a moderate caries risk (R2). Forty-six children, with high levels of ms, were expected to have a high caries risk (R3). Both R1 and R3 were treated with fluoride varnish every 18th month and R2 every 6th month. The R3 group was supplementary treated with 1% chlorhexidine gel (Corsodyl) by using either flossing combined with polishing (Flossing group), or gel in individual trays (Tray group) every third month, in two subsequent days. The mean caries development during three years was for R1 and R2, 1.5 and 3.0, respectively. For R3, the corresponding caries incidence was 2.9 in the Tray group and 2.8 in the Flossing group. Significantly less new caries was found in the R1 compared to R2 and R3, but no significant difference was found between R2 and R3 or between the two groups of R3. In conclusion both methods of professional chlorhexidine gel treatments showed a caries development corresponding to the group with moderate caries risk and could both be used for caries prevention.

  6. Migration background: a risk factor for caries development during adolescence.

    PubMed

    Julihn, Annika; Ekbom, Anders; Modéer, Thomas

    2010-12-01

    The influence of child and parental migration background on the risk of approximal caries increment in Swedish adolescents was investigated. This retrospective longitudinal register-based cohort study included all 13-yr-old adolescents (n = 18,142) who were resident in the County of Stockholm, Sweden, in 2000, and followed them up to 19 yr of age. At follow-up, 15,538 subjects were examined. Caries data [decayed, missing, and filled teeth/surfaces (DMFT/S)], were collected from a dental database. Socio-demographic determinants were collected from Swedish National Registers. After adjustments for socio-demographic confounders, logistic regression analysis revealed that adolescents with foreign-born parents, irrespective of whether the child was born in Sweden or abroad, exhibited a significantly elevated risk for approximal caries increment (DMFSa > 0), and developed, on average, 0.53 and 1.14 more approximal caries lesions, respectively, compared with their counterparts with Swedish-born parents. Furthermore, adolescents born in eastern Europe exhibited an increased risk for approximal caries increment (DMFSa > 0) and developed, on average, 1.06 more approximal caries lesions compared with Swedish-born adolescents. In conclusion, parental migration background must be considered as a risk factor for caries development during adolescence, irrespective of whether or not the adolescent was born in Sweden.

  7. The implications of the new paradigm of dental caries.

    PubMed

    Kidd, Edwina

    2011-12-01

    The caries process is the ubiquitous, natural metabolism in the biofilm that causes numerous fluctuations in pH. The interaction of this biofilm with the dental tissues may result in a caries lesion. However, lesion formation and progression can be controlled, particularly by disturbing plaque regularly with a fluoride containing toothpaste. This paradigm implies that everyone with teeth is at risk to lesion development. Treatment of caries is principally non-operative, involving plaque control, fluoride and a sensible diet. Operative dentistry repairs un-cleansable cavities and is part of plaque control. A diagnosis is a mental resting place on the way to a treatment decision. The relevant diagnostic features with respect to caries are lesion activity (active lesions require active management) and un-cleansable cavities. When teaching undergraduates, it is important that they are credited for the non-operative treatment of caries as well as for operative dentistry. This is equally important in dental practice where an appropriate skills mix of the dental team is required to deliver dental health cost-effectively. Training more dentists may be an expensive mistake as far as disease control is concerned. It is ironic that dentists make most money from operative care and specialist treatment when disease control could be delivered relatively cheaply. The key to dental health is regular and effective plaque control with a fluoride containing toothpaste, from cradle to grave.

  8. Abiotic tooth enamel.

    PubMed

    Yeom, Bongjun; Sain, Trisha; Lacevic, Naida; Bukharina, Daria; Cha, Sang-Ho; Waas, Anthony M; Arruda, Ellen M; Kotov, Nicholas A

    2017-03-01

    Tooth enamel comprises parallel microscale and nanoscale ceramic columns or prisms interlaced with a soft protein matrix. This structural motif is unusually consistent across all species from all geological eras. Such invariability-especially when juxtaposed with the diversity of other tissues-suggests the existence of a functional basis. Here we performed ex vivo replication of enamel-inspired columnar nanocomposites by sequential growth of zinc oxide nanowire carpets followed by layer-by-layer deposition of a polymeric matrix around these. We show that the mechanical properties of these nanocomposites, including hardness, are comparable to those of enamel despite the nanocomposites having a smaller hard-phase content. Our abiotic enamels have viscoelastic figures of merit (VFOM) and weight-adjusted VFOM that are similar to, or higher than, those of natural tooth enamels-we achieve values that exceed the traditional materials limits of 0.6 and 0.8, respectively. VFOM values describe resistance to vibrational damage, and our columnar composites demonstrate that light-weight materials of unusually high resistance to structural damage from shocks, environmental vibrations and oscillatory stress can be made using biomimetic design. The previously inaccessible combinations of high stiffness, damping and light weight that we achieve in these layer-by-layer composites are attributed to efficient energy dissipation in the interfacial portion of the organic phase. The in vivo contribution of this interfacial portion to macroscale deformations along the tooth's normal is maximized when the architecture is columnar, suggesting an evolutionary advantage of the columnar motif in the enamel of living species. We expect our findings to apply to all columnar composites and to lead to the development of high-performance load-bearing materials.

  9. Effect of a 3-year professional flossing program with chlorhexidine gel on approximal caries and cost of treatment in preschool children.

    PubMed

    Gisselsson, H; Birkhed, D; Björn, A L

    1994-01-01

    The aim was to evaluate the effect of chlorhexidine gel treatment on the incidence of approximal caries in preschool children. One hundred and seventeen 4-year-olds, divided into two groups, participated: (1) chlorhexidine gel group (n = 59), and (2) placebo gel group (n = 58). Group 1 was treated 4 times a year with a 1% chlorhexdine gel and group 2 with a placebo gel. Approximately 0.7 ml of gel was applied interdentally by means of a flat dental floss. A control group (group 3), which did not receive any flossing or gel treatment, was also included in the study (n = 116). After 3 years, i.e. when the children were 7 years old, the mean incidence of caries on approximal surfaces (defs), including both enamel and dentin lesions, was 2.59 in the chlorhexidine gel, 4.53 in the placebo gel and 4.20 in the control group (group 1 vs. 2 and group 1 vs. 3: p < 0.01). Mean number of approximal fillings at the end of the study, i.e. when the children were 7 years old, was 0.33 in the chlorhexidine gel, 1.04 in the placebo gel and 0.80 in the control group (group 1 vs. 2: p < 0.01; group 1 vs. 3: p < 0.05). The progression of approximal caries lesions, diagnosed on bitewing radiographs from the age of 5 to 7, was slower in the chlorhexidine than in the placebo gel group (the control group was not evaluated in this respect). A cost analysis, based on the total treatment time in minutes, showed a small gain for the flossing program.(ABSTRACT TRUNCATED AT 250 WORDS)

  10. Effect of adsorption time on the adhesion strength between salivary pellicle and human tooth enamel.

    PubMed

    Zhang, Y F; Zheng, J; Zheng, L; Zhou, Z R

    2015-02-01

    Salivary pellicle is a biofilm that is formed by the selective adsorption of salivary proteins. Almost all the functions of the salivary pellicle (lubricating properties, anti-caries properties, etc.) are closely associated with its adhesion strength to tooth surface. The objective of this study was to investigate the effect of adsorption time on the adhesion strength between salivary pellicle and human tooth enamel, aiming to understand what act as the determinant of the interfacial adhesion. In this study, human tooth enamel samples were immersed in human whole saliva in vitro to obtain a salivary pellicle on the surface of enamel. Immersion treatments lasting up to 1, 3, 10 and 60 min were conducted, respectively. Nano-scratch tests were conducted on the surface of enamel after different adsorption times. The wettability of enamel surface was measured through water contact angle. Results showed that the shear energy between salivary pellicle and enamel surface increased exponentially with the adsorption time. The adhesion force between salivary pellicle and bare enamel surface was more than twice that between salivary pellicle and salivary pellicle. It was found that both the wettability and zeta potential of enamel increased obviously after 1 min saliva-adsorption treatment, and then they almost kept stable as the adsorption time further increased. In summary, the adhesion strength between initial salivary pellicle and enamel surface was much higher than that between initial salivary pellicle and outer salivary pellicle. It seemed that electrostatic interaction contributed to the adhesion between the initial salivary pellicle and enamel surface, but not to the adhesion between the initial and outer salivary pellicle. The results would be helpful to extend the understanding of the adhesion mechanism of salivary pellicle and then to develop new artificial saliva and dental restorative materials.

  11. Validation of a Cariogenic Biofilm Model to Evaluate the Effect of Fluoride on Enamel and Root Dentine Demineralization

    PubMed Central

    2016-01-01

    Due to gingival recession both enamel and root dentine are at risk of developing caries. Both tissues are exposed to a similar environment, however there is not a validated model to evaluate the effect of fluoride on these dental substrates simultaneously. Hence, this study aimed to validate a caries model to evaluate the effect of fluoride to prevent demineralization on enamel and root-dentine. Streptococcus mutans UA159 biofilms were formed on saliva-coated bovine enamel and root dentine slabs (n = 12 per group) mounted in the same well of culture plates. The biofilms were exposed 8×/day to 10% sucrose and treated 2×/day with fluoridated solutions containing 0, 150, 450, or 1,350 ppm F; thus, simulating the use of low to high fluoride concentration toothpastes. The pH values of the culture medium was monitored 2×/day as a biofilm acidogenicity indicator. After 96 h, biofilms were collected for fluoride concentration analysis. The percentage of surface hardness loss (%SHL) was calculated for slabs. The fluoride uptake by the enamel and dentine was also determined. The model showed a dose-response because the biofilm and fluoride uptake increased and %SHL decreased at increasing fluoride concentrations (p < 0.05). Fluoride in the biofilm formed on dentine and fluoride uptake by dentine were higher than those for enamel. With the same fluoride concentration treatment, the percentage of reduction of demineralization was lower for dentine than for enamel. In conclusion, the model was validated in terms of a dose-response effect of fluoride on enamel and root dentine. Furthermore, the findings support the clinical data, suggesting that higher fluoride concentrations are necessary to control caries of root dentine than of enamel. PMID:26731743

  12. Evaluation of different Diagnostic Modalities for Diagnosis of Dental Caries: An in vivo Study

    PubMed Central

    Somani, Rani; Jaidka, Shipra; Nishad, Muhamad; Singh, Shikha; Tomar, Divya

    2016-01-01

    Aim The aim of this study was to compare and evaluate the efficacy of different diagnostic aids for diagnosis of dental caries and to compare the validity in terms of sensitivity and specificity of all four diagnostic modalities for diagnosis of caries. Materials and methods Occlusal surfaces of 100 primary and permanent molars were examined using the four diagnostic systems (visual, intraoral camera, DIAGNOdent, and DIAGNOdent with dye). These results were compared with operative intervention gold standard. Sensitivity and specificity were calculated for each diagnostic system for both enamel and dentin caries. Interrater agreement was calculated for each diagnostic system using kappa statistics. Results For both enamel and dentin caries, the highest sensitivity values were provided by DIAGNOdent (0.91 and 0.72) and lowest for visual examination on wet surface (0.60 and 0.50). For both enamel and dentin caries, the specificity was found to be highest for intraoral camera on dry surface and lowest for visual examination. The DIAGNOdent gave the highest value of interrater agreement (kappa), i.e., 0.816 as compared with 0.03 for visual examination. Conclusion The study clearly demonstrated that DIAGNO-dent was the most accurate and valid system tested for the detection of occlusal caries. It has the advantage of quantifying the mineral content, helping to improve the diagnostic efficacy and treatment and accurate assessment of fissures where the visual examination alone is not adequate, thus complementing the traditional dental examination. How to cite this article Zaidi I, Somani R, Jaidka S, Nishad M, Singh S, Tomar D. Evaluation of different Diagnostic Modalities for Diagnosis of Dental Caries: An in vivo Study. Int J Clin Pediatr Dent 2016;9(4):320-325. PMID:28127163

  13. Spectrally enhanced image resolution of tooth enamel surfaces

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Nelson, Leonard Y.; Berg, Joel H.; Seibel, Eric J.

    2012-01-01

    Short-wavelength 405 nm laser illumination of surface dental enamel using an ultrathin scanning fiber endoscope (SFE) produced enhanced detail of dental topography. The surfaces of human extracted teeth and artificial erosions were imaged with 405 nm, 444 nm, 532 nm, or 635 nm illumination lasers. The obtained images were then processed offline to compensate for any differences in the illumination beam diameters between the different lasers. Scattering and absorption coefficients for a Monte Carlo model of light propagation in dental enamel for 405 nm were scaled from published data at 532 nm and 633 nm. The value of the scattering coefficient used in the model was scaled from the coefficients at 532 nm and 633 nm by the inverse third power of wavelength. Simulations showed that the penetration depth of short-wavelength illumination is localized close to the enamel surface, while long-wavelength illumination travels much further and is backscattered from greater depths. Therefore, images obtained using short wavelength laser are not contaminated by the superposition of light reflected from enamel tissue at greater depths. Hence, the SFE with short-wavelength illumination may make it possible to visualize surface manifestations of phenomena such as demineralization, thus better aiding the clinician in the detection of early caries.

  14. Contact fatigue of human enamel: Experiments, mechanisms and modeling.

    PubMed

    Gao, S S; An, B B; Yahyazadehfar, M; Zhang, D; Arola, D D

    2016-07-01

    Cyclic contact between natural tooth structure and engineered ceramics is increasingly common. Fatigue of the enamel due to cyclic contact is rarely considered. The objectives of this investigation were to evaluate the fatigue behavior of human enamel by cyclic contact, and to assess the extent of damage over clinically relevant conditions. Cyclic contact experiments were conducted using the crowns of caries-free molars obtained from young donors. The cuspal locations were polished flat and subjected to cyclic contact with a spherical indenter of alumina at 2Hz. The progression of damage was monitored through the evolution in contact displacement, changes in the contact hysteresis and characteristics of the fracture pattern. The contact fatigue life diagram exhibited a decrease in cycles to failure with increasing cyclic load magnitude. Two distinct trends were identified, which corresponded to the development and propagation of a combination of cylindrical and radial cracks. Under contact loads of less than 400N, enamel rod decussation resisted the growth of subsurface cracks. However, at greater loads the damage progressed rapidly and accelerated fatigue failure. Overall, cyclic contact between ceramic appliances and natural tooth structure causes fatigue of the enamel. The extent of damage is dependent on the magnitude of cyclic stress and the ability of the decussation to arrest the fatigue damage.

  15. Dental biothermophotonics: How photothermal methods are winning the race with X-rays for dental caries diagnostic needs of clinical dentistry

    NASA Astrophysics Data System (ADS)

    Mandelis, A.; Jeon, R.; Matvienko, A.; Abrams, S. H.; Amaechi, B. T.

    2008-01-01

    Recent trends in biothermophotonics of teeth are presented. The presentation is centered on the development of clinical-level frequency-domain photothermal radiometry and modulated luminescence to address issues associated with the early diagnosis of demineralization caries in human teeth. Biothermophotonic principles and applications to the detection of the carious state in human teeth as embodied by laser photothermal radiometry are presented and further supported by modulated luminescence. The emphasis is on recent developments with regard to abilities of these techniques to diagnose interproximal lesions between teeth, etching with phosphoric acid and with an artificial demineralization gel in order to simulate early demineralization, as well as demineralization and remineralization of dental crown enamel and root dentin. These are lesions which normally go undetected by X-ray radiographs. Comparisons with X rays, Micro-Computed Tomography (μ-CT) and Transverse Micro-Radiography (TMR) are discussed. A theoretical model involving coupled diffuse photon density and thermal-wave fields is developed and applied to frequency scans from demineralized artificial lesions to produce quantitative values for optical and thermophysical parameters of teeth as well as the thickness of the induced lesion.

  16. The etch-bleach-seal technique for managing stained enamel defects in young permanent incisors.

    PubMed

    Wright, J Timothy

    2002-01-01

    Hypomineralized enamel defects frequently are manifest as a mottled-white appearance and can be associated with variable degrees of discrete yellow-brown intrinsic staining. Numerous treatment approaches have been proposed, ranging from bleaching to enamel reduction to restorative techniques. Bleaching of hypomineralized enamel lesions, using 1 to 2 applications (10 to 15 minutes each) of 5% sodium hypochlorite, has been applied clinically. Treatment using this approach has proven successful in removing yellow-brown discolorations from lesions in young permanent teeth. Young permanent incisors with yellow-brown intrinsic discolorations can often be treated by a simple and conservative bleaching protocol using sodium hypochlorite.

  17. Abiotic tooth enamel

    NASA Astrophysics Data System (ADS)

    Yeom, Bongjun; Sain, Trisha; Lacevic, Naida; Bukharina, Daria; Cha, Sang-Ho; Waas, Anthony M.; Arruda, Ellen M.; Kotov, Nicholas A.

    2017-03-01

    Tooth enamel comprises parallel microscale and nanoscale ceramic columns or prisms interlaced with a soft protein matrix. This structural motif is unusually consistent across all species from all geological eras. Such invariability—especially when juxtaposed with the diversity of other tissues—suggests the existence of a functional basis. Here we performed ex vivo replication of enamel-inspired columnar nanocomposites by sequential growth of zinc oxide nanowire carpets followed by layer-by-layer deposition of a polymeric matrix around these. We show that the mechanical properties of these nanocomposites, including hardness, are comparable to those of enamel despite the nanocomposites having a smaller hard-phase content. Our abiotic enamels have viscoelastic figures of merit (VFOM) and weight-adjusted VFOM that are similar to, or higher than, those of natural tooth enamels—we achieve values that exceed the traditional materials limits of 0.6 and 0.8, respectively. VFOM values describe resistance to vibrational damage, and our columnar composites demonstrate that light-weight materials of unusually high resistance to structural damage from shocks, environmental vibrations and oscillatory stress can be made using biomimetic design. The previously inaccessible combinations of high stiffness, damping and light weight that we achieve in these layer-by-layer composites are attributed to efficient energy dissipation in the interfacial portion of the organic phase. The in vivo contribution of this interfacial portion to macroscale deformations along the tooth’s normal is maximized when the architecture is columnar, suggesting an evolutionary advantage of the columnar motif in the enamel of living species. We expect our findings to apply to all columnar composites and to lead to the development of high-performance load-bearing materials.

  18. Caries experience and quantification of Streptococcus mutans and Streptococcus sobrinus in saliva of Sudanese schoolchildren.

    PubMed

    Nurelhuda, Nazik M; Al-Haroni, M; Trovik, T A; Bakken, V

    2010-01-01

    Streptococcus mutans and Streptococcus sobrinus are among the most commonly isolated bacterial species implicated as etiological agents of dental caries. Details of the composition of the oral microflora related to dental caries should aid in assessing the prevalence and risk of disease at an individual level. The aim of the present study was to determine the presence and relative amounts of S. mutans and S. sobrinus in the saliva samples obtained from schoolchildren in Khartoum State, the Sudan, and to study the association of the amounts of S. mutans and S. sobrinus with caries experience, socioeconomic status and sugar-sweetened snacks in this population. 140 samples, 30 of which were from individuals with caries experience, were examined using quantitative real-time polymerase chain reaction (qRT-PCR) with specific oligonucleotide primers. The mean ratio of fold differences of S. mutans to S. sobrinus was 0.77 (SD 5.4) and 2.29 (SD 6.0) for samples obtained from caries-free and caries-active individuals, respectively. This suggested that the proportion of S. sobrinus was higher than S.mutans in the caries-active group when compared to the caries-free group. An association was found between children with caries-active lesions and the frequent consumption of sticky desserts and higher socioeconomic status. S. sobrinus seems to be associated with caries experience in the studied population. A proposal of caries screening programs designed to test for S. sobrinus in this population may be developed.

  19. Caries prevention and adhesiveness of restorative materials submitted to cariogenic mixed biofilm.

    PubMed

    Miana, Thalita A; Fidalgo, Tatiana Kelly da Silva; Portela, Maristela Barbosa; Maia, Lucianne Cople

    2014-01-01

    This in vitro study evaluated the mechanical properties of different restorative materials submitted to cariogenic conditions with induced mixed biofilm. Extracted bovine incisors (n = 108) were divided into 3 groups (n = 36) [Group 1, resin; Group 2, glass ionomer cement (GIC); and Group 3, resin-modified GIC] and were bonded on a previously prepared enamel surface with a 25 mm² area delimited with nail varnish. Each group was then further subdivided into 3 groups and tested for shear bond strength and effectiveness in caries protection. Groups 1A-3A were tested immediately after bonding, Groups 1B-3B were tested after 5 days in brain heart infusion media, and Groups 1C-3C were tested after 5 days under cariogenic conditions with mixed biofilm. The mixed biofilm system was composed of Streptococcus mutans and Candida albicans in order to artificially create white spot lesions (WSLs). Group 1 presented the most samples with WSLs, whereas Groups 2 and Group 3 presented the highest preventive effect (P < 0.05) across all subgroups. The mean bond strengths were highest in Group 1 across all subgroups (P < 0.05). The majority of the specimens in the Group 1 subgroups presented mixed and cohesive fractures, whereas Groups 2 and 3 subgroups presented the largest amount of adhesive fractures.

  20. [Caries treatment strategy. 'Tip the balance'--drilling or not drilling].

    PubMed

    van Amerongen, J P; van Loveren, C

    1997-02-01

    Traditionally caries treatment strategy has been based on the detection of caries lesions, and directed to a restorative procedure whereby the detected defects were filled. However, the detection of lesions is not synonymous to caries diagnosis. The main purpose of caries diagnosis should be the determination of the caries activity. The diagnosis is based on several parameters, which are evaluated by an intellectual process in a dentally trained mind. The treatment should be confined, in the first instance, to stopping the caries process, and to tipping the balance in the right direction, so that the caries can cure or anyway is prevented from extending. The treatment philosophy has to be pointed to a general approach of the disease caries in the patient who it concerns on the one side, and to a local approach of individual lesions on the other hand. In the second case a lesion can be treated in a symptomatic, invasive manner or, even better, by causal, not-invasive treatment.

  1. Enamel formation and amelogenesis imperfecta.

    PubMed

    Hu, Jan C-C; Chun, Yong-Hee P; Al Hazzazzi, Turki; Simmer, James P

    2007-01-01

    Dental enamel is the epithelial-derived hard tissue covering the crowns of teeth. It is the most highly mineralized and hardest tissue in the body. Dental enamel is acellular and has no physiological means of repair outside of the protective and remineralization potential provided by saliva. Enamel is comprised of highly organized hydroxyapatite crystals that form in a defined extracellular space, the contents of which are supplied and regulated by ameloblasts. The entire process is under genetic instruction. The genetic control of amelogenesis is poorly understood, but requires the activities of multiple components that are uniquely important for dental enamel formation. Amelogenesis imperfecta (AI) is a collective designation for the variety of inherited conditions displaying isolated enamel malformations, but the designation is also used to indicate the presence of an enamel phenotype in syndromes. Recently, genetic studies have demonstrated the importance of genes encoding enamel matrix proteins in the etiology of isolated AI. Here we review the essential elements of dental enamel formation and the results of genetic analyses that have identified disease-causing mutations in genes encoding enamel matrix proteins. In addition, we provide a fresh perspective on the roles matrix proteins play in catalyzing the biomineralization of dental enamel.

  2. The Caries Phenomenon: A Timeline from Witchcraft and Superstition to Opinions of the 1500s to Today's Science.

    PubMed

    Ruby, John D; Cox, Charles F; Akimoto, Naotake; Meada, Nobuko; Momoi, Yasuko

    2010-01-01

    This historical treatise follows the documented timeline of tooth decay into today's understanding, treatment, and teaching of caries biology. Caries has been attributed to many different causes for several millennia, however, only since the late 1900s has research revealed its complex multifactorial nature. European writers of the 1600s to 1700s held views that general health, mechanical injuries, trauma, and sudden temperature changes all caused caries-holding a common belief that decay was due to chemical agents, faulty saliva, and food particles. Until the early 1800s most writers believed that caries was due to inflammation from surrounding diseased alveolar bone. Today's science has demonstrated that caries is caused by indigenous oral microorganisms becoming a dynamic biofilm, that in the presence of fermentable sugars produce organic acids capable of dissolving inorganic enamel and dentin followed by the proteolytic destruction of collagen leaving soft infected dentin. As bacteria enter the pulp, infection follows.

  3. Enamel Surface with Pit and Fissure Sealant Containing 45S5 Bioactive Glass.

    PubMed

    Yang, S-Y; Kwon, J-S; Kim, K-N; Kim, K-M

    2016-05-01

    Enamel demineralization adjacent to pit and fissure sealants leads to the formation of marginal caries, which can necessitate the replacement of existing sealants. Dental materials with bioactive glass, which releases ions that inhibit dental caries, have been studied. The purpose of this study was to evaluate the enamel surface adjacent to sealants containing 45S5 bioactive glass (BAG) under simulated microleakage between the material and the tooth in a cariogenic environment. Sealants containing 45S5BAG filler were prepared as follows: 0% 45S5BAG + 50.0% glass (BAG0 group), 12.5% 45S5BAG + 37.5% glass (BAG12.5 group), 25.0% 45S5BAG + 25.0% glass (BAG25.0 group), 37.5% 45S5BAG + 12.5% glass (BAG37.5 group), and 50.0% 45S5BAG + 0% glass (BAG50.0 group). A cured sealant disk was placed over a flat bovine enamel disk, separated by a 60-µm gap, and immersed in lactic acid solution (pH 4.0) at 37 °C for 15, 30, and 45 d. After the storage period, each enamel disk was separated from the cured sealant disk, and the enamel surface was examined with optical 3-dimensional surface profilometer, microhardness tester, and scanning electron microscopy. The results showed a significant increase in roughness and a decrease in microhardness of the enamel surface as the proportion of 45S5BAG decreased (P< 0.05). In the scanning electron microscopy images, enamel surfaces with BAG50.0 showed a smooth surface, similar to those in the control group with distilled water, even after prolonged acid storage. Additionally, an etched pattern was observed on the surface of the demineralized enamel with a decreasing proportion of 45S5BAG. Increasing the 45S5BAG filler contents of the sealants had a significant impact in preventing the demineralization of the enamel surface within microgaps between the material and the tooth when exposed to a cariogenic environment. Therefore, despite some marginal leakage, these novel sealants may be effective preventive dental materials for inhibiting

  4. Can prevention eliminate caries?

    PubMed

    O'Mullane, D

    1995-07-01

    There are four main factors involved in the carious process: at-risk tooth structure, plaque flora, fermentable carbohydrates, and time. Based on our knowledge of the carious process, four main preventive strategies have been developed over the years, namely, fluorides, fissure sealing, dietary choice, and plaque control. Fluorides are having a major impact on smooth-surface caries; hence, strategies combining fluorides and fissure sealing are very effective. However, use of fissure sealing is still problematic. Changing dietary practices with a view to reducing dental caries seems to be having little impact on a global scale. Plaque control, as practiced routinely by the majority of people, is not sufficient to result in caries reductions. Deprivation and poverty are strongly associated with high caries levels. Although the preventive strategies currently available are likely to result in lower caries levels for many, for logistical reasons and because of factors associated with deprivation and poverty, caries is likely to remain a major public health problem in most communities for the foreseeable future.

  5. Er:YAG and CTH:YAG laser radiation: contact versus non-contact enamel ablation and sonic-activated bulk composite placement

    NASA Astrophysics Data System (ADS)

    Buckova, M.; Kasparova, M.; Dostalova, T.; Jelinkova, H.; Sulc, J.; Nemec, M.; Fibrich, M.; Bradna, P.; Miyagi, M.

    2013-05-01

    Laser radiation can be used for effective caries removal and cavity preparation without significant thermal effects, collateral damage of tooth structure, or patient discomfort. The aim of this study was to compare the quality of tissue after contact or non-contact Er:YAG and CTH:YAG laser radiation ablation. The second goal was to increase the sealing ability of hard dental tissues using sonic-activated bulk filling material with change in viscosity during processing. The artificial caries was prepared in intact teeth to simulate a demineralized surface and then the Er:YAG or CTH:YAG laser radiation was applied. The enamel artificial caries was gently removed by the laser radiation and sonic-activated composite fillings were inserted. A stereomicroscope and then a scanning electron microscope were used to evaluate the enamel surface. Er:YAG contact mode ablation in enamel was quick and precise; the cavity was smooth with a keyhole shaped prism and rod relief arrangement without a smear layer. The sonic-activated filling material was consistently regularly distributed; no cracks or microleakage in the enamel were observed. CTH:YAG irradiation was able to clean but not ablate the enamel surface; in contact and also in non-contact mode there was evidence of melting and fusing of the enamel.

  6. Chemomechanical Caries Removal: A Review & Study of an Indigen-ously Developed Agent (Carie Care TM Gel) In Children

    PubMed Central

    Venkataraghavan, Karthik; Kush, Anil; Lakshminarayana, CS; Diwakar, Latha; Ravikumar, Puja; Patil, Shankargouda; Karthik, Sandhya

    2013-01-01

    The invention and application of engine driven or rotary instruments in operative treatment of carious lesions has resulted in removal of considerable toothe structure. However, with the introduction of adhesive materials for restorations, and the advent of minimal cavity design this principle has been challenged and is now considered to be too destructive to the tooth structure during caries removal. A number of techniques are available for cutting tooth tissue. The chemo mechanical method of caries removal/treatment is considered to be less painful when compared to the traditional treatment method (use of drill). The present study was carried to study the effect of an indigenously developed caries removal agent viz. Carie Care TM & its effectiveness as a chemo mechanical caries removal agent. How to cite this article: Venkataraghavan K, Kush A, Lakshminarayana CS, Diwakar L, Ravikumar P, Patil S, Karthik S. Chemomechanical Caries Removal: A Review & Study of an Indigenously Developed Agent (Carie Care TM Gel) In Children. J Int Oral Health 2013; 5(4):84-90. PMID:24155626

  7. Controlled toothbrush abrasion of softened human enamel.

    PubMed

    Voronets, J; Jaeggi, T; Buergin, W; Lussi, A

    2008-01-01

    The aim of this in vitro study was to compare toothbrush abrasion of softened enamel after brushing with two (soft and hard) toothbrushes. One hundred and fifty-six human enamel specimens were indented with a Knoop diamond. Salivary pellicle was formed in vitro over a period of 3 h. Erosive lesions were produced by means of 1% citric acid. A force-measuring device allowed a controlled toothbrushing force of 1.5 N. The specimens were brushed either in toothpaste slurry or with toothpaste in artificial saliva for 15 s. Enamel loss was calculated from the change in indentation depth of the same indent before and after abrasion. Mean surface losses (95% CI) were recorded in ten treatment groups: (1) soft toothbrush only [28 (17-39) nm]; (2) hard toothbrush only [25 (16-34) nm]; (3) soft toothbrush in Sensodyne MultiCare slurry [46 (27-65) nm]; (4) hard toothbrush in Sensodyne MultiCare slurry [45 (24-66) nm]; (5) soft toothbrush in Colgate sensation white slurry [71 (55-87) nm]; (6) hard toothbrush in Colgate sensation white slurry [85 (60-110) nm]; (7) soft toothbrush with Sensodyne MultiCare [48 (39-57) nm]; (8) hard toothbrush with Sensodyne MultiCare [40 (29-51) nm]; (9) soft toothbrush with Colgate sensation white [51 (37-65) nm]; (10) hard toothbrush with Colgate sensation white [52 (36-68) nm]. Neither soft nor hard toothbrushes produced significantly different toothbrush abrasion of softened human enamel in this model (p > 0.05).

  8. Sucrose substitutes and their role in caries prevention.

    PubMed

    Matsukubo, Takashi; Takazoe, Ichiro

    2006-06-01

    Many non- or low-cariogenic sucrose substitutes are currently available and are found as ingredients of a variety of candy, chewing gum, and drinks. Recently the role of sugar alcohols in promoting remineralisation of enamel has attracted much attention. Thus, the dental profession needs to understand the general characteristics and features of sugar substitutes to provide advice on oral health to patients as well as the general public. There are two critical requirements for sucrose substitutes, namely, being nutritionally appropriate and not being detrimental to the overall general health of the individual. The use of a greater variety of confectionary containing sucrose substitutes and the development of new substitutes with high nutritional value are essential in the battle against caries. In this paper we review in detail the characteristics of sucrose substitutes currently in use, their role in caries prevention and promotion of oral health.

  9. Epidemiology of dental caries.

    PubMed

    Winter, G B

    1990-01-01

    The most recent epidemiological data on the prevalence of dental caries in children indicate a halting of the increasing levels in many developing countries and a continuing decrease in many highly industrialized countries of the world. However, a further fall in caries levels predicted for 5-yr-old children in the U.K. has not occurred and the decline in caries may have begun to level out. 'Polarization' of caries to a minority of high-risk individuals is occurring in the developed world, with 20-25% of children accounting for more than 50% of the disease. Socio-economic factors are important in determining the proportion of high-risk children in these countries. The multifactorial aetiology of caries allows a number of different interpretations to account for changes in the prevalence of the disease with time, in both the developing and developed countries. These changes are variously ascribed to alterations in dietary habits, especially the consumption of sugar; variations in the patterns of oral hygiene; increased contact with trace elements, especially fluoride, in the environment; changes in the ecology and/or virulence of oral and dental plaque microflora and alterations in the oral protective mechanisms including the immune status. The epidemiological evidence available on the relationship of all these social, environmental and other factors to changes in the prevalence levels of caries does not, however, fully explain all the changes that have been observed. The claim that caries is no longer a public health problem is premature, as it ignores the still high proportion of individuals with tooth decay throughout the world.

  10. Amelogenin-assisted ex vivo remineralization of human enamel: Effects of supersaturation degree and fluoride concentration.

    PubMed

    Fan, Yuwei; Nelson, James R; Alvarez, Jason R; Hagan, Joseph; Berrier, Allison; Xu, Xiaoming

    2011-05-01

    The formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Calcium, phosphate and fluoride ions, and amelogenin are important ingredients for the formation of organized hydroxyapatite (HAP) crystals in vitro. However, the effects of these remineralization agents on the enamel crystal morphology have not been thoroughly studied. The objective of this study was to investigate the effects of fluoride ions, supersaturation degree and amelogenin on the crystal morphology and organization of ex vivo remineralized human enamel. Extracted third molars were sliced thin and acid-etched to provide the enamel surface for immersion in different remineralization solutions. The crystal morphology and mineral phase of the remineralized enamel surface were analyzed by field emission-scanning electron microscopy, attenuated total reflection-Fourier transformed infrared and X-ray diffraction. The concentration of fluoride and the supersaturation degree of hydroxyapatite had significant effects on the crystal morphology and crystal organization, which varied from plate-like loose crystals to rod-like densely packed nanocrystal arrays. Densely packed arrays of fluoridated hydroxyapatite nanorods were observed under the following conditions: σ(HAP)=10.2±2.0 with 1.5±0.5 mg l(-1) fluoride and 40±10 μg ml(-1) amelogenin, pH 6.8±0.4. A phase diagram summarizes the conditions that form dense or loose hydroxyapatite nanocrystal structures. This study provides the basis for the development of novel dental materials for caries management.

  11. Amelogenin-assisted ex vivo remineralization of human enamel: effects of supersaturation degree and fluoride concentration

    PubMed Central

    Fan, Yuwei; Nelson, James R.; Alvarez, Jason R.; Hagan, Joseph; Berrier, Allison; Xu, Xiaoming

    2011-01-01

    The formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Calcium, phosphate and fluoride ions and amelogenin are important ingredients for the formation of organized hydroxyapatite (HAP) crystals in vitro. However, the effects of these remineralization agents on the enamel crystal morphology have not been thoroughly studied. The objective of this study was to investigate the effects of fluoride ions, supersaturation degree and amelogenin on the crystal morphology and organization of ex vivo remineralized human enamel. Extracted third molars were sliced thin and acid-etched to provide the enamel surface for immersion in different remineralization solutions. The crystal morphology and mineral phase of the remineralized enamel surface were analyzed by FE-SEM, ATR-FTIR and XRD. The concentration of fluoride and supersaturation degree of hydroxyapatite had significant effects on the crystal morphology and crystal organization, which varied from plate-like loose crystals to rod-like densely packed nanocrystal arrays. Densely packed arrays of fluoridated hydroxyapatite nanorods were observed under the following conditions: σ(HAP) = 10.2±2.0 with fluoride 1.5±0.5 mg/L and amelogenin 40±10 µg/mL, pH 6.8±0.4. A phase diagram summarized the conditions that form dense or loose hydroxyapatite nanocrystal structures. This study provides the basis for the development of novel dental materials for caries management. PMID:21256987

  12. Effects of enamel abrasion, salivary pellicle, and measurement angle on the optical assessment of dental erosion

    NASA Astrophysics Data System (ADS)

    Lussi, Adrian; Bossen, Anke; Höschele, Christoph; Beyeler, Barbara; Megert, Brigitte; Meier, Christoph; Rakhmatullina, Ekaterina

    2012-09-01

    The present study assessed the effects of abrasion, salivary proteins, and measurement angle on the quantification of early dental erosion by the analysis of reflection intensities from enamel. Enamel from 184 caries-free human molars was used for in vitro erosion in citric acid (pH 3.6). Abrasion of the eroded enamel resulted in a 6% to 14% increase in the specular reflection intensity compared to only eroded enamel, and the reflection increase depended on the erosion degree. Nevertheless, monitoring of early erosion by reflection analysis was possible even in the abraded eroded teeth. The presence of the salivary pellicle induced up to 22% higher reflection intensities due to the smoothing of the eroded enamel by the adhered proteins. However, this measurement artifact could be significantly minimized (p<0.05) by removing the pellicle layer with 3% NaOCl solution. Change of the measurement angles from 45 to 60 deg did not improve the sensitivity of the analysis at late erosion stages. The applicability of the method for monitoring the remineralization of eroded enamel remained unclear in a demineralization/remineralization cycling model of early dental erosion in vitro.

  13. Effects of enamel abrasion, salivary pellicle, and measurement angle on the optical assessment of dental erosion.

    PubMed

    Lussi, Adrian; Bossen, Anke; Höschele, Christoph; Beyeler, Barbara; Megert, Brigitte; Meier, Christoph; Rakhmatullina, Ekaterina

    2012-09-01

    The present study assessed the effects of abrasion, salivary proteins, and measurement angle on the quantification of early dental erosion by the analysis of reflection intensities from enamel. Enamel from 184 caries-free human molars was used for in vitro erosion in citric acid (pH 3.6). Abrasion of the eroded enamel resulted in a 6% to 14% increase in the specular reflection intensity compared to only eroded enamel, and the reflection increase depended on the erosion degree. Nevertheless, monitoring of early erosion by reflection analysis was possible even in the abraded eroded teeth. The presence of the salivary pellicle induced up to 22% higher reflection intensities due to the smoothing of the eroded enamel by the adhered proteins. However, this measurement artifact could be significantly minimized (p<0.05) by removing the pellicle layer with 3% NaOCl solution. Change of the measurement angles from 45 to 60 deg did not improve the sensitivity of the analysis at late erosion stages. The applicability of the method for monitoring the remineralization of eroded enamel remained unclear in a demineralization/remineralization cycling model of early dental erosion in vitro.

  14. Presence of caries with different levels of oral hygiene.

    PubMed

    Apostolska, S; Rendzova, V; Ivanovski, K; Peeva, M; Elencevski, S

    2011-01-01

    The objective of this abstract is to examine the presence of caries in the adult population with different levels of oral hygiene; to examine the concentration of Streptococcus Mutans in saliva of patients with different levels of oral hygiene; to examine the correlation among Streptococcus Mutans, caries and level of oral hygiene. This examination was made on 50 (fifty) patients, both male and female, at the age of 20 to 65. The examinees were split into 5 groups. The examinations and sampling were done randomly at the Department of Cariology and Endodontics at the Faculty of Dental Medicine in Skopje. The microbiological researches were made at the Institute of Microbiology and parasitology at the Faculty of Medicine in Skopje. The examination of all patients was made according to a unique methodology. The results obtained indicate that the Plaque index level and the number of Streptococcus Mutans in saliva (CFU) are correlated to the number of carious teeth in all age groups except for Group V (61-65) where the Plaque index level and the level of Streptococcus Mutans in saliva were much higher compared to the number of carious teeth (51-99 and >100 CFU), particularly for examinees with prosthesis. Initial enamel caries was dominant in patients up to the age of 50, and for those older than 50 surface root caries was dominant. Initial caries was present in 28.62% of Group I and was 5.66% in Group V, unlike the root surface caries in Group 1, with 1.14%, and Group 5 with 28.30%.

  15. Effect of Fluoride Concentration on Reduction of Enamel Demineralization According to the Cariogenic Challenge.

    PubMed

    Noronha, Mayara Dos Santos; Romão, Dayse Andrade; Cury, Jaime Aparecido; Tabchoury, Cínthia Pereira Machado

    2016-01-01

    Fluoride present in toothpaste at 1,100 µg/g is considered effective on caries control. However, under high cariogenic challenge due to increasing sugar exposure, higher fluoride concentration (5,000 µg/g) could be necessary to compensate the unbalance on caries process. This was tested in a pH-cycling regimen, which evaluated the effect of fluoride concentration relative to toothpaste on reduction of enamel demineralization under conditions of two levels of cariogenic challenge. Enamel slabs (n=20) were subjected to two pH-cycling regimens, simulating 8x and 16x/day sugar exposure and were treated with solutions containing: 0 (no fluoride), 275 or 1,250 µg F/mL, resulting in 6 treatment groups: 4-h/0-F; 8-h/0-F; 4-h/275-F; 8-h/275-F; 4-h/1,250-F and 8-h/1,250-F. The 275 and 1,250 µg F/mL concentrations simulate mouth salivary dilution when 1,100 and 5,000 µg/g toothpastes are used. Enamel demineralization was assessed by surface (%SHL) and cross-sectional hardness. Fluoride taken up by enamel was also evaluated. Data were analyzed by ANOVA one-way and Tukey's test. The treatment with 1,250 µg F/mL significantly reduced %SHL compared with 275 µg F/mL (p<0.05), irrespective the level of cariogenic challenge (4-h/1,250-F vs. 4-h/275-F and 8-h/1,250-F vs 8-h/275-F comparisons, respectively). These data were supported by fluoride concentration found in enamel. These findings suggest that higher fluoride concentrations could partly compensate the greater caries risk under higher cariogenic challenge due to increasing sugar exposure.

  16. Optical-fiber-based laser-induced breakdown spectroscopy for detection of early caries

    NASA Astrophysics Data System (ADS)

    Sasazawa, Shuhei; Kakino, Satoko; Matsuura, Yuji

    2015-06-01

    A laser-induced breakdown spectroscopy (LIBS) system targeting for the in vivo analysis of tooth enamel is described. The system is planned to enable real-time analysis of teeth during laser dental treatment by utilizing a hollow optical fiber that transmits both Q-switched Nd:YAG laser light for LIBS and infrared Er:YAG laser light for tooth ablation. The sensitivity of caries detection was substantially improved by expanding the spectral region under analysis to ultraviolet (UV) light and by focusing on emission peaks of Zn in the UV region. Subsequently, early caries were distinguished from healthy teeth with accuracy rates above 80% in vitro.

  17. Genes expressed in dental enamel development are associated with molar-incisor hypomineralization.

    PubMed

    Jeremias, Fabiano; Koruyucu, Mine; Küchler, Erika C; Bayram, Merve; Tuna, Elif B; Deeley, Kathleen; Pierri, Ricardo A; Souza, Juliana F; Fragelli, Camila M B; Paschoal, Marco A B; Gencay, Koray; Seymen, Figen; Caminaga, Raquel M S; dos Santos-Pinto, Lourdes; Vieira, Alexandre R

    2013-10-01

    Genetic disturbances during dental development influence variation of number and shape of the dentition. In this study, we tested if genetic variation in enamel formation genes is associated with molar-incisor hypomineralization (MIH), also taking into consideration caries experience. DNA samples from 163 cases with MIH and 82 unaffected controls from Turkey, and 71 cases with MIH and 89 unaffected controls from Brazil were studied. Eleven markers in five genes [ameloblastin (AMBN), amelogenin (AMELX), enamelin (ENAM), tuftelin (TUFT1), and tuftelin-interacting protein 11 (TFIP11)] were genotyped by the TaqMan method. Chi-square was used to compare allele and genotype frequencies between cases with MIH and controls. In the Brazilian data, distinct caries experience within the MIH group was also tested for association with genetic variation in enamel formation genes. The ENAM rs3796704 marker was associated with MIH in both populations (Brazil: p=0.03; OR=0.28; 95% C.I.=0.06-1.0; Turkey: p=1.22e-012; OR=17.36; 95% C.I.=5.98-56.78). Associations between TFIP11 (p=0.02), ENAM (p=0.00001), and AMELX (p=0.01) could be seen with caries independent of having MIH or genomic DNA copies of Streptococcus mutans detected by real time PCR in the Brazilian sample. Several genes involved in enamel formation appear to contribute to MIH.

  18. Near-IR polarization imaging of sound and carious dental enamel

    NASA Astrophysics Data System (ADS)

    Darling, Cynthia L.; Jiao, Jane J.; Lee, Chulsung; Kang, Hobin; Fried, Daniel

    2010-02-01

    A thorough understanding of how polarized near-IR light propagates through sound and carious dental hard tissues is important for the development of dental optical imaging systems. New optical imaging tools for the detection and assessment of dental caries (dental decay) such as near-IR imaging and optical coherence tomography can exploit the enhanced contrast provided by polarization sensitivity. In this investigation, an automated system was developed to collect images for the full 16-element Mueller Matrix. The polarized light was controlled by linear polarizers and liquid crystal retarders and the 36 images were acquired as the polarized near-IR light propagates through the enamel of extracted human thin tooth sections. In previous work, we reported that polarized light is rapidly depolarized by demineralized enamel, and sound and demineralized dentin.1 The rapid depolarization of polarized light by dental caries in the near-IR provides high contrast for caries imaging and detection. In this initial study, major differences in the Mueller matrix elements were observed in both sound and demineralized enamel which supports this approach and warrants further investigation.

  19. Near-IR Polarization Imaging of Sound and Carious Dental Enamel.

    PubMed

    Darling, Cynthia L; Jiao, Jane J; Lee, Chulsung; Kang, Hobin; Fried, Daniel

    2010-01-01

    A thorough understanding of how polarized near-IR light propagates through sound and carious dental hard tissues is important for the development of dental optical imaging systems. New optical imaging tools for the detection and assessment of dental caries (dental decay) such as near-IR imaging and optical coherence tomography can exploit the enhanced contrast provided by polarization sensitivity. In this investigation, an automated system was developed to collect images for the full 16-element Mueller Matrix. The polarized light was controlled by linear polarizers and liquid crystal retarders and the 36 images were acquired as the polarized near-IR light propagates through the enamel of extracted human thin tooth sections. In previous work, we reported that polarized light is rapidly depolarized by demineralized enamel, and sound and demineralized dentin.(1) The rapid depolarization of polarized light by dental caries in the near-IR provides high contrast for caries imaging and detection. In this initial study, major differences in the Mueller matrix elements were observed in both sound and demineralized enamel which supports this approach and warrants further investigation.

  20. Genes Expressed in Dental Enamel Development Are Associated with Molar-Incisor Hypomineralization

    PubMed Central

    Jeremias, Fabiano; Koruyucu, Mine; Küchler, Erika C.; Bayram, Merve; Tuna, Elif B.; Deeley, Kathleen; Pierri, Ricardo A.; Souza, Juliana F.; Fragelli, Camila M.B.; Paschoal, Marco A.B.; Gencay, Koray; Seymen, Figen; Caminaga, Raquel M.S.; dos Santos-Pinto, Lourdes; Vieira, Alexandre R.

    2013-01-01

    Genetic disturbances during dental development influence variation of number and shape of the dentition. In this study, we tested if genetic variation in enamel formation genes is associated with molar-incisor hypomineralization (MIH), also taking into consideration caries experience. DNA samples from 163 cases with MIH and 82 unaffected controls from Turkey, and 71 cases with MIH and 89 unaffected controls from Brazil were studied. Eleven markers in five genes [ameloblastin (AMBN), amelogenin (AMELX), enamelin (ENAM), tuftelin (TUFT1), and tuftelin-interacting protein 11 (TFIP11)] were genotyped by the TaqMan method. Chi-square was used to compare allele and genotype frequencies between cases with MIH and controls. In the Brazilian data, distinct caries experience within the MIH group was also tested for association with genetic variation in enamel formation genes. The ENAM rs3796704 marker was associated with MIH in both populations (Brazil: p=0.03; OR=0.28; 95% C.I.=0.06–1.0; Turkey: p=1.22e–012; OR=17.36; 95% C.I.=5.98–56.78). Associations between TFIP11 (p=0.02), ENAM (p=0.00001), and AMELX (p=0.01) could be seen with caries independent of having MIH or genomic DNA copies of Streptococcus mutans detected by real time PCR in the Brazilian sample. Several genes involved in enamel formation appear to contribute to MIH. PMID:23790503

  1. Role of sugar and sugar substitutes in dental caries: a review.

    PubMed

    Gupta, Prahlad; Gupta, Nidhi; Pawar, Atish Prakash; Birajdar, Smita Shrishail; Natt, Amanpreet Singh; Singh, Harkanwal Preet

    2013-01-01

    Dental caries is a chronic disease which can affect us at any age. The term "caries" denotes both the disease process and its consequences, that is, the damage caused by the disease process. Dental caries has a multifactorial aetiology in which there is interplay of three principal factors: the host (saliva and teeth), the microflora (plaque), and the substrate (diet), and a fourth factor: time. The role of sugar (and other fermentable carbohydrates such as highly refined flour) as a risk factor in the initiation and progression of dental caries is overwhelming. Whether this initial demineralization proceeds to clinically detectable caries or whether the lesion is remineralized by plaque minerals depends on a number of factors, of which the amount and frequency of further sugars consumption are of utmost importance. This paper reviews the role of sugar and sugar substitutes in dental caries.

  2. Tomographic imaging of incipient dental-caries using optical coherence tomography and comparison with various modalities

    NASA Astrophysics Data System (ADS)

    Na, Jihoon; Baek, Jae Ho; Ryu, Seon Young; Lee, Changsu; Lee, Byeong Ha

    2009-07-01

    We present the optical coherence tomography (OCT) made to investigate the early dental caries in human teeth and compare its results with those taken by conventional imaging modalities including light illuminating examination (LIE), digital intra-oral radiography (DIOR), and electron probe micro analyzer (EPMA). Morphological features and caries-involved areas of the dental structure were mainly investigated by LIE, DIOR, and OCT to study the infection of the caries lesion in pits and fissures. The biochemical information acquired with EPMA and the morphological features taken with OCT in the early stage of caries were compared and analyzed to present an objective and practical index for the degree of caries. The experimental results allow us to conclude that OCT could be used to provide quantitative analysis of caries based on the reflectivity difference in the specimen.

  3. Dental Enamel Development: Proteinases and Their Enamel Matrix Substrates

    PubMed Central

    Bartlett, John D.

    2013-01-01

    This review focuses on recent discoveries and delves in detail about what is known about each of the proteins (amelogenin, ameloblastin, and enamelin) and proteinases (matrix metalloproteinase-20 and kallikrein-related peptidase-4) that are secreted into the enamel matrix. After an overview of enamel development, this review focuses on these enamel proteins by describing their nomenclature, tissue expression, functions, proteinase activation, and proteinase substrate specificity. These proteins and their respective null mice and human mutations are also evaluated to shed light on the mechanisms that cause nonsyndromic enamel malformations termed amelogenesis imperfecta. Pertinent controversies are addressed. For example, do any of these proteins have a critical function in addition to their role in enamel development? Does amelogenin initiate crystallite growth, does it inhibit crystallite growth in width and thickness, or does it do neither? Detailed examination of the null mouse literature provides unmistakable clues and/or answers to these questions, and this data is thoroughly analyzed. Striking conclusions from this analysis reveal that widely held paradigms of enamel formation are inadequate. The final section of this review weaves the recent data into a plausible new mechanism by which these enamel matrix proteins support and promote enamel development. PMID:24159389

  4. Attenuation of 1310- and 1550-nm laser light through sound dental enamel

    NASA Astrophysics Data System (ADS)

    Jones, Robert S.; Fried, Daniel

    2002-06-01

    Inexpensive laser diodes and fiber-optic technology have revived optical transillumination as a promising diagnostic method for the early detection of dental caries. The principal factor limiting transillumination through dental hard tissue is light scattering in the normal enamel and dentin. Previous studies have shown that the scattering coefficient decreases with increasing wavelength. Therefore, the near-IR region is likely to be well suited for fiber optic transillumination. The objective of this study was to measure the optical attenuation of near-IR light through dental enamel at 1310-nm and 1550-nm. These laser wavelengths are readily available due to their suitability for application to fiber optic communication. In this study the collimated transmission of laser light through polished thin sections of dental enamel for various thickness from 0.1 to 2.5 mm was measured in cuvettes of index matching fluid with n= 1.63. Beer-Lambert plots show that the attenuation coefficients are 3.1+/- 0.17cm-1 and 3.8+/- 0.17cm-1 for 1310-nm and 1550-nm, respectively. This study indicates that near-IR laser wavelengths are well-suited for the transillumination of dental enamel for caries detection since the attenuation through normal tissue is an order of magnitude less than in the visible.

  5. Dental caries: A complete changeover (Part II)-Changeover in the diagnosis and prognosis

    PubMed Central

    Carounanidy, Usha; Sathyanarayanan, R

    2009-01-01

    Realization that dental caries is a reversible, dynamic biochemical event at a micron level has changed the way the profession recognizes the caries disease and the caries lesion. The diagnosis of dental caries poses challenges due to the complex interaction of multiple endogenous causal factors. The most appropriate diagnostic aid for this purpose is the risk model of caries risk assessment. The analyses of the biological determinants provide clues to the dominant causal factor. The detection of a carious lesion has undergone a rigorous revision and revolution in order to identify the earliest mineral change so that it can be controlled without resorting to invasive management options. Apart from detection, it became mandatory to assess the extent of the lesion (noncavitated/cavitated), assess the activity status of the lesion (active/arrested), monitor the lesion progress (progression/regression over a period of time), and finally to predict the prognosis of the lesion as well as the disease. The prognosis of the disease can be best assessed by analyzing the predictor factors in caries risk assessment. The ultimate objective of such a meticulous and methodical approach aids in devising a tailor-made treatment plan, using preventing measures precisely and restorative measures minimally. This ensures the best oral health outcome of the patient. PMID:20543914

  6. Preventing Childhood Caries

    PubMed Central

    Albino, J.; Tiwari, T.

    2016-01-01

    The etiology of dental caries reflects a complex interplay of biochemical, microbial, genetic, social and physical environmental, and health-influencing behavioral factors. This review updates the literature on the efficacy of behavioral approaches to caries prevention for children up to 18 y of age. Included were studies of behavioral interventions implemented at individual, family, and community levels that assessed results in terms of reductions in caries increments. Only those reports published since 2011 were considered. Outcomes were variable, although motivational interviewing, which involves individuals in decisions about oral health within the context of their respective life circumstances, proved effective in 3 of 4 reported studies, and more definitive trials are underway. Recommendations for future research include examinations of the cost-effectiveness of interventions, as well as work focused on understanding the mechanisms underlying oral health behavior change and variables that may mediate or moderate responses to interventions. PMID:26438210

  7. Laser-induced breakdown spectroscopy of dental lesions: diagnostic and therapeutic monitoring tool

    NASA Astrophysics Data System (ADS)

    Borisova, Ekaterina; Uzunov, Tzonko; Penev, Dimitar; Genova, Tsanislava; Avramov, Latchezar

    2016-01-01

    The carious decay develops a tiny area of demineralization on the enamel, which could be detected by element analytic techniques such as laser-induced breakdown spectroscopy (LIBS). That demineralization can quickly turn into a large lesion inside the tooth, it is often discovered too late to prevent the kind of decay that leads to cavities. The same optical LIBS detection approach could be used for monitoring of the caries removal using laser ablation or drilling techniques. For LIBS measurements we applied LIBS 2500Plus (Ocean Optics Inc., Dunedin, USA) system, which consists of seven spectrometric channels, covering spectral region from 200 to 980 nm, which optical resolution 0,05 nm, the spectrometers are connected with sample fiber bundle for 7-channels spectral system to the chamber for solid and liquid samples, Q-switched Nd:YAG laser, at 1 064 nm, with energy per pulse - 40 mJ, which is applied to induce plasma in the samples. LIBS spectra were obtained after single shot of the laser in the region of pathology. Samples investigated by LIBS are extracted teeth from patients, with periodontal problems on different stage of carious lesions, and their LIBS spectra are compared with the LIBS signals obtained from normal enamel and dentine tissues to receive complete picture of the carious lesion development. The major line of our investigations is related to the development of a methodology for real-time optical feedback control during selective ablation of tooth tissues using LIBS. Tooth structures, with and without pathological changes, are compared and their LIBS element analysis is used to differentiate major changes, which occur during tooth carious process and growth.

  8. Altered inorganic composition of dental enamel and dentin in primary teeth from girls with Turner syndrome.

    PubMed

    Rizell, Sara; Kjellberg, Heidrun; Dietz, Wolfram; Norén, Jörgen G; Lundgren, Ted

    2010-04-01

    In Turner syndrome (TS) one X-chromosome is missing or defective. The amelogenin gene, located on the X-chromosome, plays a key role during the formation of dental enamel. The aim of this study was to find support for the hypothesis that impaired expression of the X-chromosome influences mineral incorporation during amelogenesis and, indirectly, during dentinogenesis. Primary tooth enamel and dentin from girls with TS were analysed and compared with the enamel and dentin of primary teeth from healthy girls. Qualitative and quantitative changes in the composition of TS enamel were found, in addition to morphological differences. Higher frequencies of subsurface lesions and rod-free zones were seen in TS enamel using polarized light microscopy. Similarly, scanning electron microscopy showed that the enamel rods from TS teeth were of atypical sizes and directions. Using X-ray microanalysis, high levels of calcium and phosphorus, and low levels of carbon, were found in both TS enamel and dentin. Using microradiography, a lower degree of mineralization was found in TS enamel. Rule induction analysis was performed to identify characteristic element patterns for TS. Low values of carbon were the most critical attributes for the outcome TS. The conclusion was that impaired expression of the X-chromosome has an impact on dental hard tissue formation.

  9. RISK INDICATORS AND RISK PREDICTORS OF DENTAL CARIES IN SCHOOLCHILDREN

    PubMed Central

    Tagliaferro, Elaine Pereira da Silva; Ambrosano, Gláucia Maria Bovi; Meneghim, Marcelo de Castro; Pereira, Antonio Carlos

    2008-01-01

    The purpose of this study was to identify risk indicators of high caries level at baseline (HCLB) based on cross-sectional data and predictors of high caries increment (HCI) based on a 7-year-follow-up examination in 6-8-year-old schoolchildren. Two hundred and six schoolchildren were examined in 1997 and in 2004 by the same two calibrated dentists, in Piracicaba, Brazil. At baseline, dental caries, presence of sealants, fluorosis, and oral hygiene status were recorded. The children's parents completed a questionnaire concerning socioeconomic level, fluoride use, dental service utilization, dietary and oral hygiene habits. HCLB and HCI were defined considering the upper quartile of the total caries experience distribution (dmfs+DMFS) and caries increment distribution, respectively. Logistic regression models were adjusted estimating the Odds Ratio (OR), 95% confidence intervals and p-values. Having white spot lesions (OR=5.25) was found to be a risk indicator of HCLB. Schoolchildren with dental fluorosis (OR=0.17) or those who brushed the teeth more than two times a day (OR=0.37) presented less probability of HCLB. The predictors of HCI were: dmfs>0 (OR=2.68) and mothers' educational level up to 8 years of schooling (OR=2.87). Clinical and socioeconomic variables were found to be risk indicators and/or predictors of dental caries in schoolchildren. PMID:19082400

  10. Incomplete caries removal: a systematic review and meta-analysis.

    PubMed

    Schwendicke, F; Dörfer, C E; Paris, S

    2013-04-01

    Increasing numbers of clinical trials have demonstrated the benefits of incomplete caries removal, in particular in the treatment of deep caries. This study systematically reviewed randomized controlled trials investigating one- or two-step incomplete compared with complete caries removal. Studies treating primary and permanent teeth with primary caries lesions requiring a restoration were analyzed. The following primary and secondary outcomes were investigated: risk of pulpal exposure, post-operative pulpal symptoms, overall failure, and caries progression. Electronic databases were screened for studies from 1967 to 2012. Cross-referencing was used to identify further articles. Odds ratios (OR) as effect estimates were calculated in a random-effects model. From 364 screened articles, 10 studies representing 1,257 patients were included. Meta-analysis showed risk reduction for both pulpal exposure (OR [95% CI] 0.31 [0.19-0.49]) and pulpal symptoms (OR 0.58 [0.31-1.10]) for teeth treated with one- or two-step incomplete excavation. Risk of failure seemed to be similar for both complete and incomplete excavation, but data for this outcome were of limited quality and inconclusive (OR 0.97 [0.64-1.46]). Based on reviewed studies, incomplete caries removal seems advantageous compared with complete excavation, especially in proximity to the pulp. However, evidence levels are currently insufficient for definitive conclusions because of high risk of bias within studies.

  11. Dental caries and associated factors in Mexican schoolchildren aged 6-13 years.

    PubMed

    Casanova-Rosado, Alejandro José; Medina-Solís, Carlo Eduardo; Casanova-Rosado, Juan Fernando; Vallejos-Sánchez, Ana Alicia; Maupomé, Gerardo; Avila-Burgos, Leticia

    2005-08-01

    The objectives of the present study were to establish dental caries prevalence (percentage with caries) and experience in the primary and permanent dentition (dmft and DMFT) of 6 to 13-year-old schoolchildren in Campeche, Mexico, and to estimate the contributing roles of the likely risk indicators. A cross-sectional study was carried out in 1,644 children aged 6-13 years. Self-administered questionnaires obtained information on social, economic, behavioral, and demographic variables. The primary dentition of 1,309 children and the permanent dentition of 1,640 children were evaluated in the oral examinations. The main outcome measures were DMFT, dmft, and SiC indices. Data were modeled using logistic regression analysis. The overall caries prevalence was 77.4%, 73.6% in the primary dentition (61.6% in 6-year-olds), and 49.4% in the permanent dentition. The dmft and DMFT indices were 2.85+/-2.73 and 1.44+/-2.05, respectively (DMFT = 3.11+/-2.62 in 12-year-olds). The SiC index was 6.05 at 12 years of age. Associated variables to dental caries in both dentitions were presence of enamel defects, presence of dental plaque, low socio-economic status, female sex, and older age. Mother's schooling was negatively associated (OR = 0.95) with caries in primary dentition. Caries experience in the primary dentition (OR = 6.02) was positively associated with caries in the permanent dentition. Dental caries status in these Mexican children was closer to the goals proposed by the WHO/FDI for 2000 than previous studies. This study has identified clinical, socio-economic, and behavioral determinants for dental caries in primary and permanent dentition on Mexican schoolchildren.

  12. Er:YAG laser irradiation to control the progression of enamel erosion: an in situ study.

    PubMed

    Scatolin, R S; Colucci, V; Lepri, T P; Alexandria, A K; Maia, L C; Galo, R; Borsatto, M C; Corona, S A M

    2015-07-01

    This in situ study evaluated the effect of Er:YAG laser irradiation in controlling the progression of enamel erosion-like lesions. Fifty-six enamel slabs (330 KHN ± 10 %) with one fourth of the surface covered with resin composite (control area) were submitted to initial erosion-like lesion formation with citric acid. The slabs were divided into two groups: irradiated with Er:YAG laser and non-irradiated. Fourteen volunteers used an intraoral palatal appliance containing two slabs, in two phases of 5 days each. During the intraoral phase, in a crossed-over design, half of the volunteers immersed the appliance in citric acid while the other half used deionized water, both for 5 min, three times per day. Enamel wear was determined by an optical 3D profilometer. ANOVA revealed that when deionized water was used as immersion solution during the intraoral phase, lower values of wear were showed when compared with the groups that were eroded with citric acid, whether irradiated or non-irradiated with Er:YAG laser. When erosion with citric acid was performed, Er:YAG laser was not able to reduce enamel wear. Small changes on enamel surface were observed when it was irradiated with Er:YAG laser. It may be concluded that Er:YAG laser irradiation did not reduce the progression of erosive lesions on enamel submitted to in situ erosion with citric acid.

  13. Dental Pulp Defence and Repair Mechanisms in Dental Caries

    PubMed Central

    Farges, Jean-Christophe; Alliot-Licht, Brigitte; Renard, Emmanuelle; Ducret, Maxime; Gaudin, Alexis; Smith, Anthony J.; Cooper, Paul R.

    2015-01-01

    Dental caries is a chronic infectious disease resulting from the penetration of oral bacteria into the enamel and dentin. Microorganisms subsequently trigger inflammatory responses in the dental pulp. These events can lead to pulp healing if the infection is not too severe following the removal of diseased enamel and dentin tissues and clinical restoration of the tooth. However, chronic inflammation often persists in the pulp despite treatment, inducing permanent loss of normal tissue and reducing innate repair capacities. For complete tooth healing the formation of a reactionary/reparative dentin barrier to distance and protect the pulp from infectious agents and restorative materials is required. Clinical and in vitro experimental data clearly indicate that dentin barrier formation only occurs when pulp inflammation and infection are minimised, thus enabling reestablishment of tissue homeostasis and health. Therefore, promoting the resolution of pulp inflammation may provide a valuable therapeutic opportunity to ensure the sustainability of dental treatments. This paper focusses on key cellular and molecular mechanisms involved in pulp responses to bacteria and in the pulpal transition between caries-induced inflammation and dentinogenic-based repair. We report, using selected examples, different strategies potentially used by odontoblasts and specialized immune cells to combat dentin-invading bacteria in vivo. PMID:26538821

  14. Caries assessment: establishing mathematical link of clinical and benchtop method

    NASA Astrophysics Data System (ADS)

    Amaechi, Bennett T.

    2009-02-01

    It is well established that the development of new technologies for early detection and quantitative monitoring of dental caries at its early stage could provide health and economic benefits ranging from timely preventive interventions to reduction of the time required for clinical trials of anti-caries agents. However, the new technologies currently used in clinical setting cannot assess and monitor caries using the actual mineral concentration within the lesion, while a laboratory-based microcomputed tomography (MCT) has been shown to possess this capability. Thus we envision the establishment of mathematical equations relating the measurements of each of the clinical technologies to that of MCT will enable the mineral concentration of lesions detected and assessed in clinical practice to be extrapolated from the equation, and this will facilitate preventitive care in dentistry to lower treatment cost. We utilize MCT and the two prominent clinical caries assessment devices (Quantitative Light-induced Fluorescence [QLF] and Diagnodent) to longitudinally monitor the development of caries in a continuous flow mixed-organisms biofilm model (artificial mouth), and then used the collected data to establish mathematical equation relating the measurements of each of the clinical technologies to that of MCT. A linear correlation was observed between the measurements of MicroCT and that of QLF and Diagnodent. Thus mineral density in a carious lesion detected and measured using QLF or Diagnodent can be extrapolated using the developed equation. This highlights the usefulness of MCT for monitoring the progress of an early caries being treated with therapeutic agents in clinical practice or trials.

  15. Methods used by Dental Practice-Based Research Network (DPBRN) dentists to diagnose dental caries

    PubMed Central

    Gordan, Valeria V.; Riley, Joseph L; Carvalho, Ricardo M.; Snyder, John; Sanderson, James L; Anderson, Mary; Gilbert, Gregg H.

    2010-01-01

    Objectives To (1) identify the methods that dentists in The Dental Practice-Based Research Network (DPBRN) use to diagnose dental caries; (2) quantify their frequency of use; and (3) test the hypothesis that certain dentist and dental practice characteristics are significantly associated with their use. Methods A questionnaire about methods used for caries diagnosis was sent to DPBRN dentists who reported doing at least some restorative dentistry; 522 dentists participated. Questions included use of dental radiographs, dental explorer, laser fluorescence, air-drying, fiber optic devices, and magnification, as used when diagnosing primary, secondary/recurrent, or non-specific caries lesions. Variations on the frequency of their use were tested using multivariate analysis and Bonferroni tests. Results Overall, the dental explorer was the instrument most commonly used to detect primary occlusal caries as well as to detect caries at the margins of existing restorations. In contrast, laser fluorescence was rarely used to help diagnose occlusal primary caries. For proximal caries, radiographs were used to help diagnose 75-100% of lesions by 96% of the DPBRN dentists. Dentists who use radiographs most often to assess proximal surfaces of posterior teeth, were significantly more likely to also report providing a higher percentage of patients with individualized caries prevention (p = .040) and seeing a higher percentage of pediatric patients (p = .001). Conclusion Use of specific diagnostic methods varied substantially. The dental explorer and radiographs are still the most commonly used diagnostic methods. PMID:21488724

  16. Predicting caries by measuring its activity using quantitative light-induced fluorescence in vivo: a 2-year caries increment analysis.

    PubMed

    Meller, C; Santamaria, R M; Connert, T; Splieth, C

    2012-01-01

    The aim of this study was to analyse the predictive power of several clinical baseline parameters and the de-/remineralisation properties of in vivo etched sites measured with quantitative light-induced fluorescence (QLF) for subsequent 2-year caries increment. At baseline, in 44 children (8.23 ± 1.5 years) two areas (diameter 2 mm) of the buccal surface of a primary posterior tooth were etched with 36% phosphoric acid gel for 1 and 4 min, respectively. The etched sites were analysed immediately after etching (ΔQ1) and 24 h (ΔQ2) later by QLF. Additionally, caries status (deft/DMFT and initial caries), approximal plaque, bleeding on probing, and the patient's current use of fluorides were recorded. In the 2-year follow-up, 29 children were re-assessed. After clinical examination, the caries increment was calculated (ΔDMFT) and correlated with the baseline clinical variables and the QLF readings. Results showed a significant positive correlation between ΔQ(1 min) and the ΔDMFT (r = 0.44, p = 0.02). The ΔDMFT was significantly correlated with the baseline deft (r = 0.56, p = 0.002), cavitated active caries lesions (r = 0.52, p = 0.003), and filled teeth (r = 0.53, p = 0.003). In a regression analysis the use of fluoridated salt (SC = -0.10) and fluoride gel (SC = -0.14) were negatively associated with ΔDMFT. In conclusion, these findings suggest that the demineralisation properties of the etched sites and the outcome of the 24-hour measurements with QLF are significantly associated with caries increment. Previous caries experience strongly correlated with caries increment in this group of children.

  17. Factors Associated with Dental Caries in a Group of American Indian Children at age 36 Months

    PubMed Central

    Warren, John J.; Blanchette, Derek; Dawson, Deborah V.; Marshall, Teresa A.; Phipps, Kathy R.; Starr, Delores; Drake, David R.

    2015-01-01

    Objectives Early childhood caries (ECC) is rampant among American Indian children, but there has been relatively little study of this problem. This paper reports on risk factors for caries for a group of American Indian children at age 36 months as part of a longitudinal study. Methods Pregnant women from a Northern Plains Tribal community were recruited to participate in a longitudinal study of caries and caries risk factors. Standardized dental examinations were completed on children and questionnaires were completed by mothers at baseline and when children were 4, 8, 12, 16, 22, 28 and 36 months of age. Examinations were surface-specific for dental caries, and the questionnaires collected data on demographic, dietary and behavioral factors. Non-parametric bivariate tests and logistic regression models were used to identify risk factors for caries at 36 months, and negative binomial regression was used to identify factors related to caries severity (dmf counts). Results Among the 232 children, and caries prevalence for cavitated lesions was 80%, with an additional 15% having only non-cavitated lesions. The mean dmfs was 9.6, and of the total dmfs, nearly 62% of affected surfaces were decayed, 31% were missing, and 7% were filled. Logistic regression identified higher added sugar beverage consumption, younger maternal age at baseline, higher maternal DMFS at baseline, and greater number of people in the household as significant (p<0.05) risk factors. Negative binomial regression found that only maternal DMFS was associated with child dmf counts. Conclusions By the age of 36 months, dental caries is nearly universal in this population of American Indian children. Caries risk factors included sugared beverage consumption, greater household size and maternal factors, but further analyses are needed to better understand caries in this population. PMID:26544674

  18. Hypoplasia-associated severe early childhood caries--a proposed definition.

    PubMed

    Caufield, P W; Li, Y; Bromage, T G

    2012-06-01

    We propose a new classification of severe early childhood caries (S-ECC): hypoplasia-associated severe early childhood caries (HAS-ECC). This form of caries affects mostly young children living at or below poverty, characterized by structurally damaged primary teeth that are particularly vulnerable to dental caries. These predisposing developmental dental defects are mainly permutations of enamel hypoplasia (EHP). Anthropologists and dental researchers consider EHP an indicator for infant and maternal stresses including malnutrition, a variety of illnesses, and adverse birthing conditions. Differentiation of HAS-ECC from other forms of early childhood caries is warranted because of its distinct etiology, clinical presentation, and eventual management. Defining HAS-ECC has important clinical implications: Therapies that control or prevent other types of caries are likely to be less effective with HAS-ECC because the structural integrity of the teeth is compromised prior to their emergence into the oral cavity. By the time these children present to the dentist, the treatment options often become limited to surgical management under general anesthesia. To prevent HAS-ECC, dentists must partner with other health providers to develop interventions that begin with pregnant mothers, with the aim of eliminating or ameliorating the covariates accompanying poverty, including better pre- and post-natal care and nutrition.

  19. Radiation-induced dental caries, prevention and treatment - A systematic review

    PubMed Central

    Gupta, Nishtha; Pal, Manoj; Rawat, Sheh; Grewal, Mandeep S.; Garg, Himani; Chauhan, Deepika; Ahlawat, Parveen; Tandon, Sarthak; Khurana, Ruparna; Pahuja, Anjali K.; Mayank, Mayur; Devnani, Bharti

    2015-01-01

    Treatment of head and neck cancers (HNCs) involves radiotherapy. Patients undergoing radiotherapy for HNCs are prone to dental complications. Radiotherapy to the head and neck region causes xerostomia and salivary gland dysfunction which dramatically increases the risk of dental caries and its sequelae. Radiation therapy (RT) also affects the dental hard tissues increasing their susceptibility to demineralization following RT. Postradiation caries is a rapidly progressing and highly destructive type of dental caries. Radiation-related caries and other dental hard tissue changes can appear within the first 3 months following RT. Hence, every effort should be focused on prevention to manage patients with severe caries. This can be accomplished through good preoperative dental treatment, frequent dental evaluation and treatment after RT (with the exception of extractions), and consistent home care that includes self-applied fluoride. Restorative management of radiation caries can be challenging. The restorative dentist must consider the altered dental substrate and a hostile oral environment when selecting restorative materials. Radiation-induced changes in enamel and dentine may compromise bonding of adhesive materials. Consequently, glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients. Counseling of patients before and after radiotherapy can be done to make them aware of the complications of radiotherapy and thus can help in preventing them. PMID:27390489

  20. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, Daniel C.

    1990-02-06

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compounds of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved.

  1. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, D.C.

    1987-11-20

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compound of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved. 2 figs.

  2. Porcelain enamel neutron absorbing material

    DOEpatents

    Iverson, Daniel C.

    1990-01-01

    A porcelain enamel composition as a neutron absorbing material can be prepared of a major proportion by weight of a cadmium compound and a minor proportion of compounds of boron, lithium and silicon. These compounds in the form of a porcelain enamel coating or layer on several alloys has been found to be particularly effective in enhancing the nuclear safety of equipment for use in the processing and storage of fissile material. The composition of the porcelain enamel coating can be tailored to match the coefficient of thermal expansion of the equipment to be coated and excellent coating adhesion can be achieved.

  3. The Use of Probiotic Strains in Caries Prevention: A Systematic Review

    PubMed Central

    Cagetti, Maria Grazia; Mastroberardino, Stefano; Milia, Egle; Cocco, Fabio; Lingström, Peter; Campus, Guglielmo

    2013-01-01

    This paper aims to provide a systematic review of the caries-prevention effect of probiotics in human. The hypothesis was that the administration of probiotic strains might play a role in caries lesion prevention and in the control of caries-related risk factors. The main relevant databases (Medline, Embase) were searched. Quality of the Randomized Clinical Trials (RCTs) was classified using the “Consolidated Standards of Reporting Trials” (CONSORT) checklist and the Impact Factor (IF) value of each journal was recorded. Sixty-six papers were identified, and 23 fulfilled the inclusion criteria. Only three studies had caries lesion development as outcome, all the others reported caries risk factors as interim evaluation. Using the CONSORT Score, the papers were coded as 4 excellent, 9 good and 10 poor. The mean IF value recorded was 1.438. Probiotics may play a role as antagonistic agent on mutans streptococci (MS), acidogenic/aciduric bacteria that contributes to the caries process. In two-thirds of the selected papers, probiotics have demonstrated the capacity to reduce MS counts in saliva and/or plaque in short-term. The effect of probiotics on the development of caries lesion seems encouraging, but to date, RCTs on this topic are insufficient to provide scientific clinical evidence. PMID:23857225

  4. Diagnosis of caries by spectral analysis of laser-induced plasma sparks

    NASA Astrophysics Data System (ADS)

    Niemz, Markolf H.

    1994-12-01

    A picosecond Nd:YLF laser system was used to remove sound and carious enamel by the mechanism of plasma-induced ablation. The plasma spark was optically imaged onto the entrance pupil of a spectrometer. The spectra were scanned between 400 - 700 nm with a typical resolution of 0.2 nm. Calcium in neutral and singly ionized states and the sodium doublet at 589 nm were observed. The second harmonic of the laser wavelength was generated in an external BBO crystal, thereby converting about 10 (mu) J of the pulse energy to radiation at 527 nm. The amplitude of the diffuse reflected second harmonic was used as a reference signal for normalization of the spectra. Several sound and artificial caries regions of different teeth were investigated. The spectra obtained from caries always showed a strong decrease in amplitude of all mineral lines, if compared to sound enamel. These results can be explained by the demineralization process of dental decay. Thus, caries infected teeth are easily distinguished from sound probes, enabling a computer controlled caries removal in the near future. The possible setup of such an automated system is discussed.

  5. A mimic study on effects of fluoride on tooth enamel structures

    NASA Astrophysics Data System (ADS)

    Ma, Guobin; Wang, Mu; Liu, Xiang Yang

    2010-03-01

    Tooth enamel is the hardest tissue in human body, and this superior mechanical property is contributed by its unique microstructures, i.e., oriented growth of rod-like apatite crystals into basic structural units called the prisms Fluoride (F^-) has been recognized to have significant effects on the physical and chemical properties of tooth enamel. However, the role of F^- on microstructures of apatite crystals is not well understood yet. Here we report a detailed investigation on the topic. Mimic in vitro growth of tooth enamel structures is performed at the biophysical conditions in simulated body fluids, using belt-like hydroxyapatite crystals as substrates It shows that F^- on the order of 0.1 mM will dramatically change the morphology of the grown crystals from irregular slabs to nano-needles, and the needles are aligned along the substrate with an average misorientation of ˜12 . Branched growth of bundles of nano-needles occurs with further increase of F^-, and finally, growth of highly porous structures as well as microspheres takes place when the F^- concentration exceeds 5 mM. In comparison with real tooth enamel structures, the relationship between enamel microstructures and tooth caries as well as fluorosis is discussed.

  6. A portable fiber-optic raman spectrometer concept for evaluation of mineral content within enamel tissue

    PubMed Central

    Yang, Shan; Roperto, Renato; Mustafa, Hathem; Teich, Sorin; Akkus, Ozan

    2017-01-01

    Background Measurement of tooth enamel mineralization using a clinically viable method is essential since variation of mineralization may be used to monitor caries risk or in assessing the effectiveness of remineralization therapy. Fiber optic Raman systems are becoming more affordable and popular in context of biomedical applications. However, the applicability of fiber optic Raman systems for measurement of mineral content within enamel tissue has not been elucidated significantly in the prior literature. Material and Methods Human teeth with varying degrees of enamel mineralization were selected. In addition alligator, boar and buffalo teeth which have increasing amount of mineral content, respectively, were also included as another set of samples. Reference Raman measurements of mineralization were performed using a high-fidelity confocal Raman microscope. Results Analysis of human teeth by research grade Raman system indicated a 2-fold difference in the Raman intensities of v1 symmetric-stretch bands of mineral-related phosphate bonds and 7-fold increase in mineral related Raman intensities of animal teeth. However, fiber optic system failed to resolve the differences in the mineralization of human teeth. Conclusions These results indicate that the sampling volume of fiber optic systems extends to the underlying dentin and that confocal aperture modification is essential to limit the sampling volume to within the enamel. Further research efforts will focus on putting together portable Raman systems integrated with confocal fiber probe. Key words:Enamel, mineral content, raman spectroscopy. PMID:28210442

  7. A new technique for analyzing trace element uptake by human enamel.

    PubMed

    Funato, Yoshiki; Matsuda, Yasuhiro; Okuyama, Katsushi; Yamamoto, Hiroko; Komatsu, Hisanori; Sano, Hidehiko

    2015-01-01

    Fluorine (F) and strontium (Sr) are key elements in the de- and remineralization of teeth. To quantitatively analyze the distribution of F and Sr, micro-particle-induced gamma/X-ray emission (PIGE/PIXE) technique was used. The cavities were prepared and filled with the fluoride- and Sr-containing restorative materials (FSCMs) in extracted human molars. The single-section enamel specimens were prepared by slicing from the buccal to lingual surface including the FSCMs. After 5 weeks of automatic pH cycling, the demineralization was calculated by integrated mineral loss (ΔIML) from transverse-microradiography. The distributions of F and Sr were analyzed by the PIGE/PIXE technique. The micro-PIGE/PIXE technique indicated a fluorine uptake difference between the enamel surface and enamel cavity wall. ΔIML of FSCMs were significantly lower than intact enamel. The micro-PIGE/PIXE technique enables measurement of F and Sr uptake from FSCMs into enamel, which would be beneficial for research on caries development and prevention.

  8. Ultrastructure of the surface of dental enamel with molar incisor hypomineralization (MIH) with and without acid etching.

    PubMed

    Bozal, Carola B; Kaplan, Andrea; Ortolani, Andrea; Cortese, Silvina G; Biondi, Ana M

    2015-01-01

    The aim of the present work was to analyze the ultrastructure and mineral composition of the surface of the enamel on a molar with MIH, with and without acid etching. A permanent tooth without clinical MIH lesions (control) and a tooth with clinical diagnosis of mild and moderate MIH, with indication for extraction, were processed with and without acid etching (H3PO4 37%, 20") for observation with scanning electron microscope (SEM) ZEISS (Supra 40) and mineral composition analysis with an EDS detector (Oxford Instruments). The control enamel showed normal prismatic surface and etching pattern. The clinically healthy enamel on the tooth with MIH revealed partial loss of prismatic pattern. The mild lesion was porous with occasional cracks. The moderate lesion was more porous, with larger cracks and many scales. The mineral composition of the affected surfaces had lower Ca and P content and higher O and C. On the tooth with MIH, even on normal looking enamel, the demineralization does not correspond to an etching pattern, and exhibits exposure of crystals with rods with rounded ends and less demineralization in the inter-prismatic spaces. Acid etching increased the presence of cracks and deep pores in the adamantine structure of the enamel with lesion. In moderate lesions, the mineral composition had higher content of Ca, P and Cl. Enamel with MIH, even on clinically intact adamantine surfaces, shows severe alterations in the ultrastructure and changes in ionic composition, which affect the acid etching pattern and may interfere with adhesion.

  9. Caries management with fluoride agents.

    PubMed

    Lam, Anty; Chu, C H

    2012-11-01

    Dental caries is the single most common, chronic oral disease of childhood. It is progressive and cumulative, and becomes more complex over time. The Surgeon General's Report on Oral Health revealed that more than 51 million school hours are lost each year as a result of dental problems. Contemporary caries management philosophy has changed from the traditional surgical approach to a medical model that emphasizes prevention. Among various strategies for caries prevention or reduction, fluoride therapy has been highly promoted. Various in-office and over-the-counter fluoride products are available for caries prevention. Dental professionals should identify and assess the caries risk level of patients and optimize the use of fluorides in caries management. Since multiple sources of fluoride exposure exist, a coordinated approach to fluoride delivery is essential.

  10. Nature vs. nurture in dental caries.

    PubMed

    Mandel, I D

    1994-10-01

    Why are some people more resistant to dental caries than others? Certainly diet plays a part, but are there hereditary factors that affect caries development? This report explores genetic components that appear related to caries resistance and susceptibility.

  11. Penetration of Streptococcus sobrinus and Streptococcus sanguinis into dental enamel.

    PubMed

    Kneist, Susanne; Nietzsche, Sandor; Küpper, Harald; Raser, Gerhard; Willershausen, Brita; Callaway, Angelika

    2015-10-01

    The aim of this pilot study was to assess the difference in virulence of acidogenic and aciduric oral streptococci in an in vitro caries model using their penetration depths into dental enamel. 30 caries-free extracted molars from 11- to 16-year-olds were cleaned ultrasonically for 1 min with de-ionized water and, after air-drying, embedded in epoxy resin. After 8-h of setting at room temperature, the specimens were ground on the buccal side with SiC-paper 1200 (particle size 13-16 μm). Enamel was removed in circular areas sized 3 mm in diameter; the mean depth of removed enamel was 230 ± 60 μm. 15 specimens each were incubated anaerobically under standardized conditions with 24 h-cultures of Streptococcus sanguinis 9S or Streptococcus sobrinus OMZ 176 in Balmelli broth at 37 ± 2 °C; the pH-values of the broths were measured at the beginning and end of each incubation cycle. After 2, 4, 6, 8, and 10 weeks 3 teeth each were fixed in 2.5% glutaraldehyde in cacodylate buffer for 24 h, washed 3× and dehydrated 30-60min by sequential washes through a series of 30-100% graded ethanol. The teeth were cut in half longitudinally; afterward, two slits were made to obtain fracture surfaces in the infected area. After critical-point-drying the fragments were gold-sputtered and viewed in a scanning electron microscope at magnifications of ×20-20,000. After 10 weeks of incubation, penetration of S. sanguinis of 11.13 ± 24.04 μm below the break edges into the enamel was observed. The invasion of S. sobrinus reached depths of 87.53 ± 76.34 μm. The difference was statistically significant (paired t test: p = 0.033). The experimental penetration depths emphasize the importance of S. sanguinis versus S. sobrinus in the context of the extended ecological plaque hypothesis.

  12. Laser soldering of enameled wires

    NASA Astrophysics Data System (ADS)

    Böhm, S.; Hemken, G.; Noack, K.

    2009-02-01

    In electrical connections with enameled copper wires, isolation material residue can be found in the solder area when the coating is not stripped. This residue can lead to mechanical and electrical problems. In electronic devices and MEMS, quality requirements increase with rising thermal requirements for electrical contacts made from enameled copper wire. Examples for this exist in the area of automotive electronics, consumer electronics and in the field of machine design. Typical products with electrical connecting which use enameled wires include: micro-phones and speakers (especially for mobile phones), coil forms, small transformers, relays, clock coils, and so on. Due to increasing thermal and electrical requirements, the manufacturer of enameled wires continuously develops new isolating materials for the improvement of isolation classes, thermal resistance, etc. When using current bonding and solder processes, there exist problems for contacting enameled copper wire with these insulation layers. Therefore the Institute of Joining and Welding, Department Micro Joining developed a laser based solder process with which enamels copper wires can enable high quality electrical connections without a preceding stripping process.

  13. Enhancing caries resistance with a short-pulsed CO2 9.3-μm laser: a laboratory study (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Rechmann, Peter; Rechmann, Beate M.; Groves, William H.; Le, Charles; Rapozo-Hilo, Marcia L.; Featherstone, John D. B.

    2016-02-01

    The objective of this laboratory study was to test whether irradiation with a new 9.3µm microsecond short-pulsed CO2-laser enhances enamel caries resistance with and without additional fluoride applications. 101 human enamel samples were divided into 7 groups. Each group was treated with different laser parameters (Carbon-dioxide laser, wavelength 9.3µm, 43Hz pulse-repetition rate, pulse duration between 3μs to 7μs (1.5mJ/pulse to 2.9mJ/pulse). Using a pH-cycling model and cross-sectional microhardness testing determined the mean relative mineral loss delta Z (∆Z) for each group. The pH-cycling was performed with or without additional fluoride. The CO2 9.3μm short-pulsed laser energy rendered enamel caries resistant with and without additional fluoride use.

  14. Role of Sugar and Sugar Substitutes in Dental Caries: A Review

    PubMed Central

    Gupta, Nidhi; Pawar, Atish Prakash; Birajdar, Smita Shrishail; Natt, Amanpreet Singh; Singh, Harkanwal Preet

    2013-01-01

    Dental caries is a chronic disease which can affect us at any age. The term “caries” denotes both the disease process and its consequences, that is, the damage caused by the disease process. Dental caries has a multifactorial aetiology in which there is interplay of three principal factors: the host (saliva and teeth), the microflora (plaque), and the substrate (diet), and a fourth factor: time. The role of sugar (and other fermentable carbohydrates such as highly refined flour) as a risk factor in the initiation and progression of dental caries is overwhelming. Whether this initial demineralization proceeds to clinically detectable caries or whether the lesion is remineralized by plaque minerals depends on a number of factors, of which the amount and frequency of further sugars consumption are of utmost importance. This paper reviews the role of sugar and sugar substitutes in dental caries. PMID:24490079

  15. First step toward translation of thermophotonic lock-in imaging to dentistry as an early caries detection technology

    NASA Astrophysics Data System (ADS)

    Ojaghi, Ashkan; Parkhimchyk, Artur; Tabatabaei, Nima

    2016-09-01

    Early detection of the most prevalent oral disease worldwide, i.e., dental caries, still remains as one of the major challenges in dentistry. The current dental standard of care relies on caries detection methods, such as visual inspection and x-ray radiography, which lack the sufficient specificity and sensitivity to detect caries at early stages of formation when they can be healed. We report on the feasibility of early caries detection in a clinically and commercially viable thermophotonic imaging system. The system incorporates intensity-modulated laser light along with a low-cost long-wavelength infrared (LWIR; 8 to 14 μm) camera, providing diagnostic contrast based on the enhanced light absorption of early caries. The LWIR camera is highly suitable for integration into clinical platforms because of its low weight and cost. In addition, through theoretical modeling, we show that LWIR detection enhances the diagnostic contrast due to the minimal LWIR transmittance of enamel and suppression of the masking effect of the direct thermal Planck emission. Diagnostic performance of the system and its detection threshold are experimentally evaluated by monitoring the inception and progression of artificially induced occlusal and smooth surface caries. The results are suggestive of the suitability of the developed LWIR system for detecting early dental caries.

  16. Contact microradiographic analysis of feline tooth resorptive lesions.

    PubMed

    Ohba, S; Kiba, H; Kuwabara, M; Yoshida, H; Koide, F; Takeishi, M

    1993-04-01

    Feline tooth resorptive lesions were studied using contact microradiographic analysis of ground sections. Contact microdiagram films were developed with a PIAS-imaging device, and decalcification patterns were evaluated, revealing a clear boundary between normal tissue and the resorptive area, which was different from the image of dental caries in humans. By contrasting analysis, decalcification signs appearing in human caries were not observed in feline resorptive lesions.

  17. Dental caries development among African-American children: results from a 4-year longitudinal study

    PubMed Central

    Lim, Sungwoo; Tellez, Marisol; Ismail, Amid I.

    2015-01-01

    Objective To examine dental caries development and caries risk factors among preschool African-American children from low-income families in Detroit, Michigan over a four- year window. Methods Data came from a representative sample of 1,021 children (zero to five years) and their caregivers in Detroit. The baseline participants in 2002–03 (W1) were reexamined in 2004–05 (W2) and 2007 (W3). Caries was measured using the International Caries Detection and Assessment System. Bivariate and multivariate analyses for repeated data were conducted to explore associations between caries increment outcomes and demographics, access to dental care, oral health-related behaviors, and social and physical environments. Results The mean number of new NCCL (non-cavitated caries lesions) was 2.8 between W1 and W2 and 2.6 between W2 and W3, while the mean number of new CCL (cavitated caries lesions) was 2.0 and 2.0, respectively, during the same time periods. In younger children (< three years old in W1) higher number of new NCCL than new CCL were observed in both W1–W2 and W2–W3. The risk of new NCCL was associated with child’s soda intake and caregiver’s age. For the risk of new CCL, significant risk factors included baseline NCCL, baseline CCL, as well as child’s age. Baseline caries and child’s soda intake were also associated with the risk of developing new decayed, missing, and filled tooth surfaces. Conclusions Higher number of new NCCL relative to CCL was developed among low-income Africa-American children during early childhood. New caries development was associated with baseline caries and child’s soda intake. PMID:25441657

  18. Effects of fluoride on in vitro enamel demineralization analyzed by ¹⁹F MAS-NMR.

    PubMed

    Mohammed, N R; Kent, N W; Lynch, R J M; Karpukhina, N; Hill, R; Anderson, P

    2013-01-01

    The mechanistic action of fluoride on inhibition of enamel demineralization was investigated using (19)F magic angle spinning nuclear magnetic resonance (MAS-NMR). The aim of this study was to monitor the fluoride-mineral phase formed on the enamel as a function of the concentration of fluoride ions [F(-)] in the demineralizing medium. The secondary aim was to investigate fluorapatite formation on enamel in the mechanism of fluoride anti-caries efficacy. Enamel blocks were immersed into demineralization solutions of 0.1 M acetic acid (pH 4) with increasing concentrations of fluoride up to 2,262 ppm. At and below 45 ppm [F(-)] in the solution, (19)F MAS-NMR showed fluoride-substituted apatite formation, and above 45 ppm, calcium fluoride (CaF2) formed in increasing proportions. Further increases in [F(-)] caused no further reduction in demineralization, but increased the proportion of CaF2 formed. Additionally, the combined effect of strontium and fluoride on enamel demineralization was also investigated using (19)F MAS-NMR. The presence of 43 ppm [Sr(2+)] in addition to 45 ppm [F(-)] increases the fraction of fluoride-substituted apatite, but delays formation of CaF2 when compared to the demineralization of enamel in fluoride-only solution.

  19. Oriented and Ordered Biomimetic Remineralization of the Surface of Demineralized Dental Enamel Using HAP@ACP Nanoparticles Guided by Glycine.

    PubMed

    Wang, Haorong; Xiao, Zuohui; Yang, Jie; Lu, Danyang; Kishen, Anil; Li, Yanqiu; Chen, Zhen; Que, Kehua; Zhang, Qian; Deng, Xuliang; Yang, Xiaoping; Cai, Qing; Chen, Ning; Cong, Changhong; Guan, Binbin; Li, Ting; Zhang, Xu

    2017-01-12

    Achieving oriented and ordered remineralization on the surface of demineralized dental enamel, thereby restoring the satisfactory mechanical properties approaching those of sound enamel, is still a challenge for dentists. To mimic the natural biomineralization approach for enamel remineralization, the biological process of enamel development proteins, such as amelogenin, was simulated in this study. In this work, carboxymethyl chitosan (CMC) conjugated with alendronate (ALN) was applied to stabilize amorphous calcium phosphate (ACP) to form CMC/ACP nanoparticles. Sodium hypochlorite (NaClO) functioned as the protease which decompose amelogenin in vivo to degrade the CMC-ALN matrix and generate HAP@ACP core-shell nanoparticles. Finally, when guided by 10 mM glycine (Gly), HAP@ACP nanoparticles can arrange orderly and subsequently transform from an amorphous phase to well-ordered rod-like apatite crystals to achieve oriented and ordered biomimetic remineralization on acid-etched enamel surfaces. This biomimetic remineralization process is achieved through the oriented attachment (OA) of nanoparticles based on non-classical crystallization theory. These results indicate that finding and developing analogues of natural proteins such as amelogenin involved in the biomineralization by natural macromolecular polymers and imitating the process of biomineralization would be an effective strategy for enamel remineralization. Furthermore, this method represents a promising method for the management of early caries in minimal invasive dentistry (MID).

  20. Effect of a hydrophobic tooth coating on gingival health, mutans streptococci, and enamel demineralization in adolescents with fixed orthodontic appliances.

    PubMed

    Fornell, Ann-Charlott; Sköld-Larsson, Kerstin; Hallgren, Anders; Bergstrand, Fredrik; Twetman, Svante

    2002-01-01

    The effect of an anti-adhesive enamel coating on plaque accumulation, gingival health, and enamel demineralization was evaluated in 39 adolescents undergoing treatment with fixed orthodontic appliances using a prospective split-mouth design. Immediately after bracket insertion, the polymer was randomly applied after enamel etching to the buccal surfaces of the teeth in the left or right upper quadrant, leaving the opposite quadrant as an untreated control (218 test and 216 control teeth). Reapplications were carried out every 3rd month during the course or the study. The following data were collected at baseline and at designated follow-ups: visible plaque index, total viable counts and proportion of mutans streptococci in plaque samples, gingival bleeding index, and amount of gingival crevicular fluid. The incidence of enamel demineralization adjacent to the appliances was scored clinically at the termination of the orthodontic treatment. The observation time ranged from 6-24 months, during which the participants used fluoride rinses and toothpaste daily. A slightly impaired gingival health and increased levels or mutans streptococci compared with baseline was disclosed during the treatment. Five subjects showed enamel demineralization on a total of 30 teeth at the time of de-bonding. The results indicated no statistically significant differences between the enamel-coated and untreated teeth with regard to the studied variables at any follow-up. In conclusion, the present findings did not support a clinically beneficial effect of the polymeric tooth coating in a low-caries group of adolescents treated with fixed orthodontic appliances.

  1. Oriented and Ordered Biomimetic Remineralization of the Surface of Demineralized Dental Enamel Using HAP@ACP Nanoparticles Guided by Glycine

    NASA Astrophysics Data System (ADS)

    Wang, Haorong; Xiao, Zuohui; Yang, Jie; Lu, Danyang; Kishen, Anil; Li, Yanqiu; Chen, Zhen; Que, Kehua; Zhang, Qian; Deng, Xuliang; Yang, Xiaoping; Cai, Qing; Chen, Ning; Cong, Changhong; Guan, Binbin; Li, Ting; Zhang, Xu

    2017-01-01

    Achieving oriented and ordered remineralization on the surface of demineralized dental enamel, thereby restoring the satisfactory mechanical properties approaching those of sound enamel, is still a challenge for dentists. To mimic the natural biomineralization approach for enamel remineralization, the biological process of enamel development proteins, such as amelogenin, was simulated in this study. In this work, carboxymethyl chitosan (CMC) conjugated with alendronate (ALN) was applied to stabilize amorphous calcium phosphate (ACP) to form CMC/ACP nanoparticles. Sodium hypochlorite (NaClO) functioned as the protease which decompose amelogenin in vivo to degrade the CMC-ALN matrix and generate HAP@ACP core-shell nanoparticles. Finally, when guided by 10 mM glycine (Gly), HAP@ACP nanoparticles can arrange orderly and subsequently transform from an amorphous phase to well-ordered rod-like apatite crystals to achieve oriented and ordered biomimetic remineralization on acid-etched enamel surfaces. This biomimetic remineralization process is achieved through the oriented attachment (OA) of nanoparticles based on non-classical crystallization theory. These results indicate that finding and developing analogues of natural proteins such as amelogenin involved in the biomineralization by natural macromolecular polymers and imitating the process of biomineralization would be an effective strategy for enamel remineralization. Furthermore, this method represents a promising method for the management of early caries in minimal invasive dentistry (MID).

  2. Oriented and Ordered Biomimetic Remineralization of the Surface of Demineralized Dental Enamel Using HAP@ACP Nanoparticles Guided by Glycine

    PubMed Central

    Wang, Haorong; Xiao, Zuohui; Yang, Jie; Lu, Danyang; Kishen, Anil; Li, Yanqiu; Chen, Zhen; Que, Kehua; Zhang, Qian; Deng, Xuliang; Yang, Xiaoping; Cai, Qing; Chen, Ning; Cong, Changhong; Guan, Binbin; Li, Ting; Zhang, Xu

    2017-01-01

    Achieving oriented and ordered remineralization on the surface of demineralized dental enamel, thereby restoring the satisfactory mechanical properties approaching those of sound enamel, is still a challenge for dentists. To mimic the natural biomineralization approach for enamel remineralization, the biological process of enamel development proteins, such as amelogenin, was simulated in this study. In this work, carboxymethyl chitosan (CMC) conjugated with alendronate (ALN) was applied to stabilize amorphous calcium phosphate (ACP) to form CMC/ACP nanoparticles. Sodium hypochlorite (NaClO) functioned as the protease which decompose amelogenin in vivo to degrade the CMC-ALN matrix and generate HAP@ACP core-shell nanoparticles. Finally, when guided by 10 mM glycine (Gly), HAP@ACP nanoparticles can arrange orderly and subsequently transform from an amorphous phase to well-ordered rod-like apatite crystals to achieve oriented and ordered biomimetic remineralization on acid-etched enamel surfaces. This biomimetic remineralization process is achieved through the oriented attachment (OA) of nanoparticles based on non-classical crystallization theory. These results indicate that finding and developing analogues of natural proteins such as amelogenin involved in the biomineralization by natural macromolecular polymers and imitating the process of biomineralization would be an effective strategy for enamel remineralization. Furthermore, this method represents a promising method for the management of early caries in minimal invasive dentistry (MID). PMID:28079165

  3. Effect of high energy X-ray irradiation on the nano-mechanical properties of human enamel and dentine.

    PubMed

    Liang, Xue; Zhang, Jing Yang; Cheng, Iek Ka; Li, Ji Yao

    2016-01-01

    Radiotherapy for malignancies in the head and neck can cause common complications that can result in tooth damage that are also known as radiation caries. The aim of this study was to examine damage to the surface topography and calculate changes in friction behavior and the nano-mechanical properties (elastic modulus, nanohardness and friction coefficient) of enamel and dentine from extracted human third molars caused by exposure to radiation. Enamel and dentine samples from 50 human third molars were randomly assigned to four test groups or a control group. The test groups were exposed to high energy X-rays at 2 Gy/day, 5 days/week for 5 days (10 Gy group), 15 days (30 Gy group), 25 days (50 Gy group), 35 days (70 Gy group); the control group was not exposed. The nanohardness, elastic modulus, and friction coefficient were analyzed using a Hysitron Triboindenter. The nano-mechanical properties of both enamel and dentine showed significant dose-response relationships. The nanohardness and elastic modulus were most variable between 30-50 Gy, while the friction coefficient was most variable between 0-10 Gy for dentine and 30-50 Gy for enamel. After exposure to X-rays, the fracture resistance of the teeth clearly decreased (rapidly increasing friction coefficient with increasing doses under the same load), and they were more fragile. These nano-mechanical changes in dental hard tissue may increase the susceptibility to caries. Radiotherapy caused nano-mechanical changes in dentine and enamel that were dose related. The key doses were 30-50 Gy and the key time points occurred during the 15th-25th days of treatment, which is when application of measures to prevent radiation caries should be considered.

  4. Topical laser application enhances enamel fluoride uptake and tribological properties.

    PubMed

    Jeng, Y-R; Lin, T-T; Huang, J-S; Peng, S-R; Shieh, D-B

    2013-07-01

    Topical fluoride treatment prevents dental caries. However, the resulting calcium-fluoride-like deposits are soft and have poor wear resistance; therefore, frequent treatment is required. Lasers quickly heat surfaces and can be made portable and suitable for oral remedies. We examined the morphology, nanohardness, elastic modulus, nanowear, and fluoride uptake of fluoride-treated enamel followed by CO2 laser irradiation for 5 and 10 sec, respectively. We found that laser treatments significantly increased the mechanical properties of the calcium-fluoride-like deposits. The wear resistance of the calcium-fluoride-like deposits improved about 34% after laser irradiation for 5 sec and about 40% following irradiation for 10 sec. We also found that laser treatments increased fluoride uptake by at least 23%. Overall, laser treatment significantly improved fluoride incorporation into dental tissue and the wear resistance of the protective calcium-fluoride layer.

  5. Elemental analysis of caries-affected root dentin and artificially demineralized dentin

    PubMed Central

    Sung, Young-Hye; Son, Ho-Hyun; Yi, Keewook

    2016-01-01

    Objectives This study aimed to analyze the mineral composition of naturally- and artificially-produced caries-affected root dentin and to determine the elemental incorporation of resin-modified glass ionomer (RMGI) into the demineralized dentin. Materials and Methods Box-formed cavities were prepared on buccal and lingual root surfaces of sound human premolars (n = 15). One cavity was exposed to a microbial caries model using a strain of Streptococcus mutans. The other cavity was subjected to a chemical model under pH cycling. Premolars and molars with root surface caries were used as a natural caries model (n = 15). Outer caries lesion was removed using a carbide bur and a hand excavator under a dyeing technique and restored with RMGI (FujiII LC, GC Corp.). The weight percentages of calcium (Ca), phosphate (P), and strontium (Sr) and the widths of demineralized dentin were determined by electron probe microanalysis and compared among the groups using ANOVA and Tukey test (p < 0.05). Results There was a pattern of demineralization in all models, as visualized with scanning electron microscopy. Artificial models induced greater losses of Ca and P and larger widths of demineralized dentin than did a natural caries model (p < 0.05). Sr was diffused into the demineralized dentin layer from RMGI. Conclusions Both microbial and chemical caries models produced similar patterns of mineral composition on the caries-affected dentin. However, the artificial lesions had a relatively larger extent of demineralization than did the natural lesions. RMGI was incorporated into the superficial layer of the caries-affected dentin. PMID:27847746

  6. Effect of fluoride in phosphate buffer solution on bonding to artificially carious enamel.

    PubMed

    Wang, Hao; Shimada, Yasushi; Tagami, Junji

    2007-09-01

    The purpose of the present study was to evaluate the effect of fluoride on resin bonding to artificially carious enamel. Specimens from demineralized human enamel sections were prepared using two commercially available adhesives (Clearfil SE Bond, Kuraray; Single Bond, 3M) and a composite resin (Clearfil AP-X, Kuraray) according to manufacturers' instructions. They were then immersed in phosphate buffered saline solution with varied fluoride concentrations at 0, 0.1, 0.5, 1, and 10 ppm. After immersion in each solution for one, three, or seven days, microshear bond strength was measured. The bond strengths of both adhesive systems to artificially carious enamel significantly increased after immersion in fluoride-phosphate buffer solution. Based on the findings obtained, we thus proposed not to remove the white enamel lesions for bonding in the clinic. They might be preserved and treated using fluoride applications.

  7. Calcium release rates from tooth enamel treated with dentifrices containing whitening agents and abrasives.

    PubMed

    Araujo, Danilo Barral; Silva, Luciana Rodrigues; de Araujo, Roberto Paulo Correia

    2010-01-01

    Tooth whitening agents containing hydrogen peroxide and carbamide peroxide are used frequently in esthetic dental procedures. However, lesions on the enamel surface have been attributed to the action of these products. Using conventional procedures for separating and isolating biological structures, powdered enamel was obtained and treated with hydrogen peroxide, carbamide peroxide, and sodium bicarbonate, ingredients typically found in dentifrices. The enamel was exposed to different pH levels, and atomic emission spectrometry was used to determine calcium release rates. As the pH level increased, the rate of calcium release from enamel treated with dentifrices containing whitening agents decreased. Carbamide peroxide produced the lowest amount of decalcification, while sodium bicarbonate produced the highest release rates at all pH levels.

  8. Ozone therapy in the management and prevention of caries.

    PubMed

    Almaz, Merve Erkmen; Sönmez, Işıl Şaroğlu

    2015-01-01

    The purpose of this article was to assess the effectiveness of ozone therapy in the management and prevention of caries, reviewing clinical and in vitro studies. Ozone has proven to be effective against gram-negative and gram-positive bacteria, viruses, and fungi. In dentistry, most of the published articles are based on ozone's antimicrobial effects and the treatment of caries. Most of the clinical studies reported ozone to be a promising alternative to conventional methods for caries management. However, a few studies have shown ozone to be insufficient for preventing caries and reducing microorganisms in open occlusal carious lesions. Ozone might be a useful tool to reduce and control oral infectious microorganisms in dental plaque and dental cavity. However, the results of in vitro studies are controversial; while some researchers reported that ozone therapy had a minimal or no effect on the viability of microorganisms, others suggested ozone to be highly effective in killing both gram-positive and gram-negative oral microorganisms. Therefore, more evidence is required before ozone can be accepted as an alternative to present methods for the management and prevention of caries.

  9. Caries prevention in a community-dwelling older population.

    PubMed

    Powell, L V; Persson, R E; Kiyak, H A; Hujoel, P P

    1999-01-01

    A clinical trial was conducted to compare the effect of different caries-preventive strategies on caries progression in lower-income, ethnically diverse persons 60 years of age and older. Two hundred and ninety-seven subjects were randomized into one of five experimental groups. Group 1 received usual care from a public health department or a private practitioner. Group 2 received an educational program of 2 h duration implemented twice a year. Group 3 received the educational program plus a 0.12% chlorhexidine rinse weekly. Group 4 received the education and chlorhexidine interventions and a fluoride varnish application twice a year. Group 5 received all the above interventions as well as scaling and root planing every 6 months throughout the 3-year study. A carious event was defined as the onset of a carious lesion, a filling, or an extraction on a surface which was sound at baseline. Two hundred and one subjects remained in the study for the 3-year period. Groups that received usual intraoral procedures (groups 3, 4, and 5) had a 27% reduction for coronal caries events (p = 0.09) and 23% for root caries events (p = 0.15), when compared to the groups that received no intraoral procedures (groups 1 and 2). Routine preventive treatments may have had only a small-to-moderate effect upon caries development.

  10. Assessment of dental-caries using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Na, Jihoon; Baek, Jae H.; Choi, Eun S.; Ryu, Seon Y.; Chang, Ju-wan; Lee, Chang S.; Lee, Byeong H.

    2006-02-01

    We employed OCT imaging technique to study the human teeth infected with the caries lesion in fit and fissure. A time domain OCT system using a rapid-scanning optical delay line enabled high speed imaging of extracted teeth. The OCT images presented the morphological feature and caries-involved area of the dental structure with a high resolution of ~14 μm. The OCT images could be utilized to diagnose the disease, while a signal along the axial direction could provide quantitative analysis of the disease based on the reflectivity differences in the specimen. We investigated the influence of caries in human teeth with several imaging tools such as light illuminating exam, digital intra-oral radiography and electron probe micro analyzer, which provided the distributions of chemical compositions, mainly calcium and phosphate in hard tissues. The biochemical changes acquired from EPMA and the morphological features acquired from OCT in the early stage of caries were compared and analyzed to present more objectively practical index for translating the degree of caries.

  11. Environmental causes of enamel defects.

    PubMed

    Brook, A H; Fearne, J M; Smith, J M

    1997-01-01

    A large number of causes of enamel defects, both environmental and genetic, have been described. However, many of these are derived from case histories and studies of individual conditions. What is needed now is a systematic investigation of the problem. The first requirement in exploring the aetiology further is the standardization of both the clinical diagnosis and the descriptive terminology. This has been provided by the Fédération Dentaire Internationale Developmental Defects of Enamel Index. Comparing studies using standardized methods, including this index, has highlighted areas for closer investigation. The total prevalence of enamel defects in a population needs to be established as a baseline for studies on aetiology. Sixty-eight per cent of 1518 school children in London have enamel defects in the permanent dentition, with 10.5% having 10 or more teeth affected and 14.6% having hypoplasia, i.e. missing enamel. These findings are in contrast to the 37% with hypoplasia found in a group of third to fifth century Romano-Britons from Dorset, England, suggesting further consideration of possible environmental and genetic differences between the two populations. An overall long-term study of dental development in low birth weight children has shown significantly more (P < 0.001) enamel defects related to major health problems during the neonatal period. By using standardized, reproducible criteria in prevalence studies to gain an overview of the problem and then studying specific groups or conditions, it is possible to identify general and specific factors in the aetiology of enamel defects and investigate further the varying role of genetic and environmental effects.

  12. Amelogenin in Enamel Tissue Engineering

    PubMed Central

    2016-01-01

    In this chapter the basic premises, the recent findings and the future challenges in the use of amelogenin for enamel tissue engineering are being discoursed on. Results emerging from the experiments performed to assess the fundamental physicochemical mechanisms of the interaction of amelogenin, the main protein of the enamel matrix, and the growing crystals of apatite, are mentioned, alongside a moderately comprehensive literature review of the subject at hand. The clinical importance of understanding this protein/mineral interaction at the nanoscale are highlighted as well as the potential for tooth enamel to act as an excellent model system for studying some of the essential aspects of biomineralization processes in general. The dominant paradigm stating that amelogenin directs the uniaxial growth of apatite crystals in enamel by slowing down the growth of (hk0) faces on which it adheres is being questioned based on the results demonstrating the ability of amelogenin to promote the nucleation and crystal growth of apatite under constant titration conditions designed to mimic those present in the developing enamel matrix. The role of numerous minor components of the enamel matrix is being highlighted as essential and impossible to compensate for by utilizing its more abundant ingredients only. It is concluded that the three major aspects of amelogenesis outlined hereby – (1) the assembly of amelogenin and other enamel matrix proteins, (2) the proteolytic activity, and (3) crystallization – need to be in precise synergy with each other in order for the grounds for the proper imitation of amelogenesis in the lab to be created. PMID:26545753

  13. Polarized light propagation through sound and carious enamel at 1310-nm

    NASA Astrophysics Data System (ADS)

    Darling, Cynthia L.; Fried, Daniel

    2006-02-01

    A thorough understanding of how polarized near-IR light propagates through sound and carious dental hard tissues is important for the development of dental optical imaging systems. New optical imaging tools for the detection and assessment of dental caries (dental decay) such as near-IR imaging and optical coherence tomography can exploit the enhanced contrast provided by polarization sensitivity. Stokes polarimetry was used to monitor the state of polarization (SOP) and degree of polarization (DOP) of incident linearly and circularly polarized light as it propagates through extracted human whole teeth, thin tooth sections and single apatite crystals. These measurements at 1310-nm suggest that the DOP is maintained through sound tooth enamel and transparent dentin and that circularly polarized light is typically depolarized more rapidly than linearly light. Polarized light is rapidly depolarized by demineralized enamel and sound and demineralized dentin. The rapid depolarization of polarized light by dental caries in the near-IR provides high contrast for caries imaging and detection.

  14. FT-Raman spectroscopic characterization of enamel surfaces irradiated with Nd:YAG and Er:YAG lasers

    PubMed Central

    Shahabi, Sima; Fekrazad, Reza; Johari, Maryam; Chiniforoush, Nasim; Rezaei, Yashar

    2016-01-01

    Background. Despite recent advances in dental caries prevention, caries is common and remains a serious health problem. Laser irradiation is one of the most common methods in preventive measures in recent years. Raman spectroscopy technique is utilized to study the microcrystalline structure of dental enamel. In this study, FT-Raman spectroscopy was used to evaluate chemical changes in enamel structure irradiated with Nd:YAG and Er:YAG lasers. Methods. We used 15 freshly-extracted, non-carious, human molars that were treated as follows: No treatment was carried out in group A (control group); Group B was irradiated with Er:YAG laser for 10 seconds under air and water spray; and Group C was irradiated with Nd:YAG laser for 10 seconds under air and water spray. After treatment, the samples were analyzed by FT-Raman spectroscopy. Results. The carbonate content evaluation with regard to the integrated area under the curve (1065/960 cm–1) exhibited a significant reduction in its ratio in groups B and C. The organic content (2935/960 cm-1) area exhibited a significant decrease after laser irradiation in group B and C. Conclusion. The results showed that the mineral and organic matrices of enamel structure were affected by laser irradiation; therefore, it might be a suitable method for caries prevention. PMID:28096945

  15. Development of fibre-optic confocal microscopy for detection and diagnosis of dental caries.

    PubMed

    Rousseau, C; Poland, S; Girkin, J M; Hall, A F; Whitters, C J

    2007-01-01

    We report on the development of a fibre-optics-based confocal imaging system for the detection and potential diagnosis of early dental caries. A novel optical instrument, capable of recording axial profiles through caries lesions using single-mode optical fibres, has been developed. The practical study illustrates that miniature confocal devices based around single-mode optical fibres may provide additional diagnostic information for the general dental practitioner.

  16. Dental caries prevalence among type II diabetic and nondiabetic adults attending a hospital

    PubMed Central

    Malvania, Ekta A.; Sheth, Sona A.; Sharma, Ashish S.; Mansuri, Saloni; Shaikh, Faizan; Sahani, Saloni

    2016-01-01

    Objectives: Diabetes mellitus (DM) is a common chronic metabolic disorder which affects millions of people. At present, India has the highest incidence of diabetes worldwide. Several oral lesions and conditions are associated with diabetes. However, there is a lack of consensus among researchers regarding the relationship between DM and dental caries. Hence, the present study was carried out to assess the dental caries prevalence among type II diabetic and nondiabetic adults attending a hospital in Ahmedabad city. Materials and Methods: A hospital-based cross-sectional study was conducted. One hundred and twenty diabetics individuals attending the diabetic Outpatient Department (OPD) and age and sex-matched 120 nondiabetic individuals from general OPD were included in the study. The data were gathered through semi-close-ended questionnaire and clinical examination. Dental caries was assessed by using the World Health Organization's 2013 proforma. Data was analyzed by applying Student's independent t-test or one-way analysis of variance. Results: Dental caries prevalence among the diabetic group was 73.33% and 33.33% among the nondiabetic group. Dental caries prevalence and mean dental caries was significantly higher among uncontrolled diabetic individuals than that among controlled diabetic individuals. Duration of the disease and dental caries prevalence did not show any significant difference. Conclusion: Dental caries prevalence was significantly high among diabetic individuals compared with nondiabetic individuals. Close collaboration between the patients, healthcare units, and oral health professionals could be a way of improving diabetic patients' general and oral health. PMID:28217542

  17. Nutrition and dental caries.

    PubMed

    Mobley, Connie C

    2003-04-01

    Promotion of sound dietary practices is an essential component of caries management, along with fluoride exposure and oral hygiene practices. Scientific discoveries have lead to better understanding of the caries process, the ever-expanding food supply, and the interaction between the two. Fermentable carbohydrates interact dynamically with oral bacteria and saliva, and these foods will continue to be a major part of a healthful diet. Dental health professionals can serve their patients and the public by providing comprehensive oral health care and by promoting lifestyle behaviors to improve oral and general health within the time constraints of their practice. Dietary advice given should not contradict general health principles when providing practical guidance to reduce caries risk. The following principles should guide messages: * Encourage balanced diets based on moderation and variety as depicted by the Food Guide Pyramid and the Dietary Guidelines for Americans to provide a sound approach. Avoid references to "bad" foods and focus on "good" diets that include a variety of foods. * Give examples of how combining and sequencing foods can enhance mastication, saliva production, and oral clearance at each eating occasion. Combining dairy foods with sugary foods, raw foods with cooked, and protein-rich foods with acidogenic foods are all good examples. Suggest that eating and drinking be followed by cariostatic foods such as xylitol chewing gum. * Drink water to satisfy thirst and hydration needs as often as possible. Restrict consumption of sweetened beverages to meal and snack times when they can be combined with other cariostatic foods. * When a patient reports excessive dietary intake of a fermentable carbohydrate to the point of displacing other important foods in the diet, identify alternatives that will help the patient maintain or achieve a healthy body weight, oral health status, and a nutrient-dense intake.

  18. Fraunhofer diffraction of light by human enamel.

    PubMed

    O'Brien, W J

    1988-02-01

    Fraunhofer diffraction patterns of human enamel samples were photographed with a helium-neon laser beam (lambda = 633 nm). The first-order diffraction angle was in reasonable agreement with a prediction based upon enamel prisms acting as a two-dimensional grating. These results support the hypothesis that enamel diffracts light because of the periodic structure of enamel prisms with interprismatic spaces, which act as slits.

  19. Estimation of the enamel and dentin mineral content from the refractive index.

    PubMed

    Hariri, I; Sadr, A; Nakashima, S; Shimada, Y; Tagami, J; Sumi, Y

    2013-01-01

    Recent advances in the field of optics have enabled accurate and localized measurement of optical properties of biological substrates. This work aimed to elucidate the relationship between the local refractive index (n) and mineral content (MC) of enamel and dentin. De- and remineralized lesions in bovine enamel and dentin blocks were sectioned into 300- to 400-µm-thick slices, and placed on a metal plate to capture images of sound, de- and remineralized regions transversely by optical coherence tomography. Mean n at each depth level of the lesion (20- or 40-µm steps for enamel or dentin) was measured by the optical path length-matching method and used to plot n through lesion depth. The specimens were further polished and processed for transverse microradiography for analysis of MC. The n and MC ranged from 1.52 to 1.63 and 50 to 87 (vol.%) in enamel, and from 1.43 to 1.57 and 11 to 48 (vol.%) in dentin, respectively. Strong, positive linear correlations were found between n and MC (Pearson's r = 0.95 and 0.91 for de- and remineralized enamel, and r = 0.94 and 0.91 for dentin, respectively, p < 0.001). Experimental data were validated with a theoretical calculation of n from MC. De- and remineralization of enamel and dentin resulted in measurable changes of n, and, in turn, MC changes of the tissue could be estimated with good accuracy from this long-known optical property by the new analytical approach. Compositional changes of enamel crystallites after remineralization affect n.

  20. Glycemic control with insulin prevents progression of dental caries and caries-related periodontitis in diabetic WBN/KobSlc rats.

    PubMed

    Nakahara, Yutaka; Sano, Tomoya; Kodama, Yasushi; Ozaki, Kiyokazu; Matsuura, Tetsuro

    2013-07-01

    We have previously reported that dental caries progress in spontaneously and chemically induced diabetic rodent models. The aim of this study was to clarify the relationship between hyperglycemia and dental caries by evaluating the preventive effect of glycemic control with insulin on the progression of the lesions in diabetic rats. Male WBN/KobSlc rats aged 15 weeks were divided into groups of spontaneously diabetic rats (intact group), spontaneously diabetic rats with insulin treatment (INS group), alloxan-induced prolonged diabetic rats (AL group), and alloxan-induced prolonged diabetic rats with insulin treatment (AL + INS group). The animals were killed at 90 weeks of age, and their oral tissue was examined. Dental caries and periodontitis were frequently detected in the intact group, and the lesions were enhanced in the AL group (in which there was an increased duration of diabetes). Meanwhile, glycemic control with insulin reduced the incidence and severity of dental caries and periodontitis in the INS group, and the effects became more pronounced in the AL + INS group. In conclusion, glycemic control by insulin prevented the progression of dental caries and caries-related periodontitis in the diabetic rats.

  1. Enamel ultrastructure in pigmented hypomaturation amelogenesis imperfecta.

    PubMed

    Wright, J T; Lord, V; Robinson, C; Shore, R

    1992-10-01

    Hypomaturation amelogenesis imperfecta (AI) is a hereditary condition of enamel that is presumed to result from defects during the maturation stage of enamel development. This study characterized the enamel ultrastructure and enamel crystallite morphology, as well as the distribution of organic material in enamel affected with pigmented hypomaturation AI. Enamel exhibiting autosomal recessive pigmented hypomaturation AI was sectioned or fractured and examined using light microscopy, scanning electron microscopy and transmission electron microscopy. Enamel samples were treated with 30% NaOCl or 8 M urea to remove organic components and determine the effect of deproteinization on crystallite morphology. These were compared with untreated normal enamel samples. The enamel crystallites in hypomaturation AI exhibited considerable variability in size and morphology. Examination of deproteinized tissue indicated that the AI crystallites had a thick coating, presumably of organic or partially mineralized material, which was not visible in normal enamel. The results of this investigation provide further evidence that hypomaturation AI is associated with the retention of organic material that is most probably enamel protein. Enamel protein retention is likely to be involved in the inhibition of normal crystallite growth resulting in the morphological crystallite abnormalities associated with this disorder.

  2. Genome-wide association Scan of dental caries in the permanent dentition

    PubMed Central

    2012-01-01

    Background Over 90% of adults aged 20 years or older with permanent teeth have suffered from dental caries leading to pain, infection, or even tooth loss. Although caries prevalence has decreased over the past decade, there are still about 23% of dentate adults who have untreated carious lesions in the US. Dental caries is a complex disorder affected by both individual susceptibility and environmental factors. Approximately 35-55% of caries phenotypic variation in the permanent dentition is attributable to genes, though few specific caries genes have been identified. Therefore, we conducted the first genome-wide association study (GWAS) to identify genes affecting susceptibility to caries in adults. Methods Five independent cohorts were included in this study, totaling more than 7000 participants. For each participant, dental caries was assessed and genetic markers (single nucleotide polymorphisms, SNPs) were genotyped or imputed across the entire genome. Due to the heterogeneity among the five cohorts regarding age, genotyping platform, quality of dental caries assessment, and study design, we first conducted genome-wide association (GWA) analyses on each of the five independent cohorts separately. We then performed three meta-analyses to combine results for: (i) the comparatively younger, Appalachian cohorts (N = 1483) with well-assessed caries phenotype, (ii) the comparatively older, non-Appalachian cohorts (N = 5960) with inferior caries phenotypes, and (iii) all five cohorts (N = 7443). Top ranking genetic loci within and across meta-analyses were scrutinized for biologically plausible roles on caries. Results Different sets of genes were nominated across the three meta-analyses, especially between the younger and older age cohorts. In general, we identified several suggestive loci (P-value ≤ 10E-05) within or near genes with plausible biological roles for dental caries, including RPS6KA2 and PTK2B, involved in p38-depenedent MAPK signaling

  3. Baseline Caries Risk Assessment as a Predictor of Caries Incidence

    PubMed Central

    Chaffee, Benjamin W.; Cheng, Jing; Featherstone, John D. B.

    2015-01-01

    Few studies have evaluated clinical outcomes following caries risk assessment in large datasets that reflect risk assessments performed during routine practice. OBJECTIVE From clinical records, compare 18-month caries incidence according to baseline caries risk designation. METHODS For this retrospective cohort study, data were collected from electronic records of non-edentulous adult patients who completed an oral examination and caries risk assessment (CRA) at a university instructional clinic from 2007 to 2012 (N=18,004 baseline patients). The primary outcome was the number of new decayed/restored teeth from the initial CRA to the ensuing oral examination, through June 30, 2013 (N=4468 patients with follow-up). We obtained doubly-robust estimates for 18-month caries increment by baseline CRA category (low, moderate, high, extreme), adjusted for patient characteristics (age, sex, payer type, race/ethnicity, number of teeth), provider type, and calendar year. RESULTS Adjusted mean decayed, restored tooth (DFT) increment from baseline to follow-up was greater with each rising category of baseline caries risk, from low (0.94), moderate (1.26), high (1.79), to extreme (3.26). The percentage of patients with any newly affected teeth (DFT increment >0) was similar among low-risk and moderate-risk patients (cumulative incidence ratio, RR: 1.01; 95% confidence interval, CI: 0.83, 1.23), but was increased relative to low-risk patients among high-risk (RR: 1.28; 95% CI: 1.10, 1.52), and extreme-risk patients (RR: 1.52; 95% CI: 1.23, 1.87). CONCLUSIONS These results lend evidence that baseline caries risk predicts future caries in this setting, supporting the use of caries risk assessment to identify candidate patients for more intensive preventive therapy. PMID:25731155

  4. Evaluating performance of dental caries detection methods among third-year dental students

    PubMed Central

    2013-01-01

    Background Reliable caries detection is a cornerstone in the modern caries treatment schema. This study aimed to evaluate adopting traditional and new caries detection methods by third-year dental students. Methods Fifty-seven students were given lectures on caries detection, after which they evaluated 27 extracted carious teeth using traditional clinical assessment (CE), Nyvad’s, and ICDAS methods. On three teeth they also performed DIAGNOdent pen® (LF) scanning. Histological scores of the sectioned teeth (ICDAS, LF) and activity estimations of the lesions by the supervisors were used as golden standards (Nyvad, CE). For the ICDAS method , sensitivity and specificity were calculated using dentine caries (D3) as a cut-off point. Mean ICC and kappa values were calculated to evaluate interexaminer agreement for all lesions and methods. Spearman’s correlation coefficient evaluated LF scanning. Results ICDAS method presented good sensitivity (0.78) and specificity (0.87). The inter-examiner agreement for different methods was fair or good (CE ICC = 0.69, κ = 0.53; Nyvad’s method ICC = 0.68, κ = 0.48, ICDAS ICC = 0.66, κ = 0.47). Variation in LF values was the greatest with lesions extending to middle third of dentin. In that case, the Spearman’s correlation coefficient was also the weakest. Conclusions To follow the guidelines by the European Core Curriculum on Cariology, the third year dental students are introduced to methods for detecting lesion depth and assessing lesion activity as well as using new caries detection methods. Their performance in estimating lesion depth is good, and fair to good in estimating lesion activity even after basic training only. PMID:24314305

  5. Effects of the CO II laser combined with fluoridated toothpaste on human dental enamel demineralization

    NASA Astrophysics Data System (ADS)

    Azevedo Rodrigues, Lidiany Karla; Alvarez Vidigal, Evelyn; Silva Soares, Luís Eduardo; Abrahão Martin, Airton; Brugnera-Júnior, Aldo; Aparecida Zanin, Fátima Antonia; Nobre dos Santos, Marinês

    2006-02-01

    This in vitro pilot study investigated the CO II laser effects on demineralization inhibition in sound human dental enamel. Thirty six human enamel specimens were used and randomly assigned to 6 groups, as follows: I) Control; II) 1W; III) 2W; IV) 3W; V) 4W; VI) 5W. Group I one was kept as control and others were irradiated using a pulsed CO II laser (λ=10.6 μm) with low crescent potencies. Fourier Transform Raman Spectroscopy was used to study the surface composition of specimens after irradiation. One specimen from each group was analyzed by Scanning Electron Microscopy and the remaining ones were submitted to an 8-day pH cycling model with use of fluoridated toothpaste twice a day. After pH-cycling, the cross-sectional microhardness was performed for mineral loss (ΔZ) quantification. The data were analyzed by ANOVA and Tuckey test (α=0.05). No changes were found either in SEM photomicrographies or RAMAN Spectra of the specimens in all groups. The ΔZ values (n=5; mean+/-SD) for I-VI groups were: 1741.6+/-725.3a 1782.7+/-639.0a 1427.2+/-237.0a 1780.6+/-552.4a 1385.2+/-602.2a 943.1+/-228.1a respectively. The highest percentage of caries inhibition was found in group VI (45.8%); however the differences between ΔZ of the groups were not statistically significant. The use of CO II laser with low fluencies did not prevent more caries development than the use of fluoridated toothpaste, even though group VI had present good results in caries inhibition. Energy densities higher than 0.0125 J/cm 2 should be used to promote chemical or morphological changes on enamel surface, which are able of inhibiting mineral.

  6. The oral microbiome and the immunobiology of periodontal disease and caries.

    PubMed

    Costalonga, Massimo; Herzberg, Mark C

    2014-12-01

    The composition of the oral microbiome differs from one intraoral site to another, reflecting in part the host response and immune capacity at each site. By focusing on two major oral infections, periodontal disease and caries, new principles of disease emerge. Periodontal disease affects the soft tissues and bone that support the teeth. Caries is a unique infection of the dental hard tissues. The initiation of both diseases is marked by an increase in the complexity of the microbiome. In periodontitis, pathobionts and keystone pathogens such as Porphyromonas gingivalis appear in greater proportion than in health. As a keystone pathogen, P. gingivalis impairs host immune responses and appears necessary but not sufficient to cause periodontitis. Historically, dental caries had been causally linked to Streptococcus mutans. Contemporary microbiome studies now indicate that singular pathogens are not obvious in either caries or periodontitis. Both diseases appear to result from a perturbation among relatively minor constituents in local microbial communities resulting in dysbiosis. Emergent consortia of the minor members of the respective microbiomes act synergistically to stress the ability of the host to respond and protect. In periodontal disease, host protection first occurs at the level of innate gingival epithelial immunity. Secretory IgA antibody and other salivary antimicrobial systems also act against periodontopathic and cariogenic consortia. When the gingival immune response is impaired, periodontal tissue pathology results when matrix metalloproteinases are released from neutrophils and T cells mediate alveolar bone loss. In caries, several species are acidogenic and aciduric and appear to work synergistically to promote demineralization of the enamel and dentin. Whereas technically possible, particularly for caries, vaccines are unlikely to be commercialized in the near future because of the low morbidity of caries and periodontitis.

  7. The oral microbiome and the immunobiology of periodontal disease and caries

    PubMed Central

    Costalonga, Massimo; Herzberg, Mark C.

    2015-01-01

    The composition of the oral microbiome differs from one intraoral site to another, reflecting in part the host response and immune capacity at each site. By focusing on two major oral infections, periodontal disease and caries, new principles of disease emerge. Periodontal disease affects the soft tissues and bone that support the teeth. Caries is a unique infection of the dental hard tissues. The initiation of both diseases is marked by an increase in the complexity of the microbiome. In periodontitis, pathobionts and keystone pathogens such as Porphyromonas gingivalis appear in greater proportion than in health. As a keystone pathogen, P. gingivalis impairs host immune responses and appears necessary but not sufficient to cause periodontitis. Historically, dental caries had been causally linked to Streptococcus mutans. Contemporary microbiome studies now indicate that singular pathogens are not obvious in either caries or periodontitis. Both diseases appear to result from a perturbation among relatively minor constituents in local microbial communities resulting in dysbiosis. Emergent consortia of the minor members of the respective microbiomes act synergistically to stress the ability of the host to respond and protect. In periodontal disease, host protection first occurs at the level of innate gingival epithelial immunity. Secretory IgA antibody and other salivary antimicrobial systems also act against periodontopathic and cariogenic consortia. When the gingival immune response is impaired, periodontal tissue pathology results when matrix metalloproteinases are released from neutrophils and T cells mediate alveolar bone loss. In caries, several species are acidogenic and aciduric and appear to work synergistically to promote demineralization of the enamel and dentin. Whereas technically possible, particularly for caries, vaccines are unlikely to be commercialized in the near future because of the low morbidity of caries and periodontitis. PMID:25447398

  8. Potential mechanism for the laser-fluoride effect on enamel demineralization.

    PubMed

    Liu, Y; Hsu, C-Y S; Teo, C M J; Teoh, S H

    2013-01-01

    Laser-induced prevention of dental caries has been studied extensively. However, the cariostatic mechanisms of a combined fluoride-laser treatment are not well-understood. Using micro- computed tomography (micro-CT), we quantified the effect of fluoride and/or Er:YAG laser treatment on enamel demineralization. The mean mineral loss (%/V) for each group was 4,870 ± 1,434 (fluoride followed by laser treatment), 6,341 ± 2,204 (laser treatment), 7,669 ± 2,255 (fluoride treatment), and 10,779 ± 2,936 (control). The preventive effect of the laser (p < 0.001) and fluoride (p = 0.010) treatment was statistically significant. Characterized by micro-x-ray diffraction (XRD) analysis, the significant contraction in the a-axis after both laser and combined laser/fluoride treatment was revealed (both p < 0.05). In conclusion, subablative low-energy Er:YAG laser irradiation following fluoride treatment may instantaneously transform enamel hydroxyapatite into fluoridated hydroxyapatite to reduce enamel solubility as a preventive treatment for enamel demineralization.

  9. Managing Carious Lesions: Consensus Recommendations on Terminology.

    PubMed

    Innes, N P T; Frencken, J E; Bjørndal, L; Maltz, M; Manton, D J; Ricketts, D; Van Landuyt, K; Banerjee, A; Campus, G; Doméjean, S; Fontana, M; Leal, S; Lo, E; Machiulskiene, V; Schulte, A; Splieth, C; Zandona, A; Schwendicke, F

    2016-05-01

    Variation in the terminology used to describe clinical management of carious lesions has contributed to a lack of clarity in the scientific literature and beyond. In this article, the International Caries Consensus Collaboration presents 1) issues around terminology, a scoping review of current words used in the literature for caries removal techniques, and 2) agreed terms and definitions, explaining how these were decided.Dental cariesis the name of the disease, and thecarious lesionis the consequence and manifestation of the disease-the signs or symptoms of the disease. The termdental caries managementshould be limited to situations involving control of the disease through preventive and noninvasive means at a patient level, whereascarious lesion managementcontrols the disease symptoms at the tooth level. While it is not possible to directly relate the visual appearance of carious lesions' clinical manifestations to the histopathology, we have based the terminology around the clinical consequences of disease (soft, leathery, firm, and hard dentine). Approaches to carious tissue removal are defined: 1)selective removal of carious tissue-includingselective removal to soft dentineandselective removal to firm dentine; 2)stepwise removal-including stage 1,selective removal to soft dentine, and stage 2,selective removal to firm dentine6 to 12 mo later; and 3)nonselective removal to hard dentine-formerly known ascomplete caries removal(technique no longer recommended). Adoption of these terms, around managing dental caries and its sequelae, will facilitate improved understanding and communication among researchers and within dental educators and the wider clinical dentistry community.

  10. Saliva-promoted adhesion of Streptococcus mutans MT8148 associates with dental plaque and caries experience.

    PubMed

    Shimotoyodome, A; Kobayashi, H; Tokimitsu, I; Hase, T; Inoue, T; Matsukubo, T; Takaesu, Y

    2007-01-01

    Colonization of enamel surfaces by Streptococcus mutans is thought to be initiated by the attachment of bacteria to a saliva-derived conditioning film (acquired pellicle). However, the clinical relevance of the contribution of saliva-promoted S. mutans adhesion in biofilm formation has not yet been fully elucidated. The aim of this study was to correlate saliva-promoted S. mutans adhesion with biofilm formation in humans. We correlated all measurements of salivary factors and dental plaque formation in 70 healthy subjects. Dental plaque development after thorough professional teeth cleaning correlated positively with S. mutans adhesion onto saliva-coated hydroxyapatite pellets and the glycoprotein content of either parotid or whole saliva. Saliva-promoted S. mutans adhesion and glycoprotein content were also positively correlated with each other in parotid and whole saliva. By contrast, neither salivary mutans streptococci, Lactobacillus nor Candida correlated with biofilm formation. Parotid saliva-mediated S. mutans adhesion was significantly higher in 12 caries-experienced (CE) subjects than in 9 caries-inexperienced (CI) subjects. Salivary S. mutans adhesion was significantly less (p < 0.01) in the CI group than in the CE group. In conclusion, the present findings suggest the initial S. mutans adhesion, modulated by salivary protein adsorption onto the enamel surface, as a possible correlate of susceptibility to dental plaque and caries.

  11. Xylitol-induced changes of enamel microhardness paralleled by microradiographic observations.

    PubMed

    Scheinin, A; Söderling, E; Scheinin, U; Glass, R L; Kallio, M L

    1993-08-01

    The study, aimed to analyze the feasibility of a prospective field study, was carried out in Polynesian children with rampant untreated caries. Slabs of bovine enamel were inserted for 8-12 days in cavities and subsequently replaced by permanent fillings. Before use, the surface of the slab was polished, and one half predemineralized and tested for microhardness. The follow-up in 30 subjects involved 54 slabs, 30 from negative controls with no added sweets and 24 from subjects receiving 20 g/day of xylitol in candy. The microhardness of the slabs was reassessed, and the difference between measurements calculated and tested for significance. The differences between the groups were highly significant, the predemineralized halves showing pronounced rehardening at exposure to xylitol. Parallel microradiographic observations conformed with the above findings. The results indicate that the use of a noncariogenic sweetener might be of value in high caries risk subjects.

  12. The effect of enamel proteins on erosion

    NASA Astrophysics Data System (ADS)

    Baumann, T.; Carvalho, T. S.; Lussi, A.

    2015-10-01

    Enamel proteins form a scaffold for growing hydroxyapatite crystals during enamel formation. They are then almost completely degraded during enamel maturation, resulting in a protein content of only 1% (w/v) in mature enamel. Nevertheless, this small amount of remaining proteins has important effects on the mechanical and structural properties of enamel and on the electrostatic properties of its surface. To analyze how enamel proteins affect tooth erosion, human enamel specimens were deproteinated. Surface microhardness (SMH), surface reflection intensity (SRI) and calcium release of both deproteinated and control specimens were monitored while continuously eroding them. The deproteination itself already reduced the initial SMH and SRI of the enamel significantly (p < 0.001 and p < 0.01). During the course of erosion, the progression of all three evaluated parameters differed significantly between the two groups (p < 0.001 for each). The deproteinated enamel lost its SMH and SRI faster, and released more calcium than the control group, but these differences were only significant at later stages of erosion, where not only surface softening but surface loss can be observed. We conclude that enamel proteins have a significant effect on erosion, protecting the enamel and slowing down the progression of erosion when irreversible surface loss starts to occur.

  13. Molecular mechanisms of dental enamel formation.

    PubMed

    Simmer, J P; Fincham, A G

    1995-01-01

    Tooth enamel is a unique mineralized tissue in that it is acellular, is more highly mineralized, and is comprised of individual crystallites that are larger and more oriented than other mineralized tissues. Dental enamel forms by matrix-mediated biomineralization. Enamel crystallites precipitate from a supersaturated solution within a well-delineated biological compartment. Mature enamel crystallites are comprised of non-stoichiometric carbonated calcium hydroxyapatite. The earliest crystallites appear suddenly at the dentino-enamel junction (DEJ) as rapidly growing thin ribbons. The shape and growth patterns of these crystallites can be interpreted as evidence for a precursor phase of octacalcium phosphate (OCP). An OCP crystal displays on its (100) face a surface that may act as a template for hydroxyapatite (OHAp) precipitation. Octacalcium phosphate is less stable than hydroxyapatite and can hydrolyze to OHAp. During this process, one unit cell of octacalcium phosphate is converted into two unit cells of hydroxyapatite. During the precipitati