Science.gov

Sample records for dental arch study

  1. Dental arch asymmetry

    PubMed Central

    Al-Zubair, Nabil Muhsen

    2014-01-01

    Objective: This study was conducted to assess the dental arch asymmetry in a Yemeni sample aged (18-25) years. Materials and Methods: The investigation involved clinical examination of 1479 adults; only 253 (129 females, 124 males) out of the total sample were selected to fulfill the criteria for the study sample. Study models were constructed and evaluated to measure mandibular arch dimensions. Three linear distances were utilized on each side on the dental arch: Incisal-canine distance, canine-molar distance and incisal-molar distance, which represent the dental arch segmental measurements. Results: When applying “t-test” at P < 0.05, no significant differences were found between the right and left canine-molar, incisal-canine and incisal-molar distances in both dental arches for both sexes. The greater variation (0.30 mm) was observed between right and left canine-molar distance in the maxillary dental arch in male and the smaller (0.04 mm) in the mandibular dental arch between the right and left canine-molar distance in females. Conclusion: The findings of the present study revealed a symmetrical pattern of dental arches, since the right and left sides showed no statistically significant difference. In general, it can be observed that the measurements related to the central incisors and canines have the widest range of reading and give the impression that the location of central incisor and canines to each other and to other teeth is the strongest factor in determining the dental arch asymmetry. PMID:24966774

  2. Dental arch analysis system.

    PubMed

    Mutinelli, Sabrina; Cozzani, Mauro; Manfredi, Mario; Siciliani, Giuseppe

    2004-01-01

    The purpose of our research is to describe a computerized method, which enables orthodontists and researchers to analyze variation of dental arch form and dimension. The analysis system is composed of two independent parts: the database, where the images of scanned dental casts are stored, and the software. The operator uses the software to identify some landmarks on dental cast images. Corresponding distances are calculated (interincisive, intercanine and intermolar widths and the curve axis). Then the software algorithms calculate and draw the curves passing trough the selected landmarks (conics, catenary, cubic spline and polynomial curves). In the chosen curves the arch length is measured. The dental cast data, recorded at different times of the subject's life or in different steps of orthodontic treatment, are compared in order to evaluate the change in dimension (arch length and width) and form (shape). The statistical analysis of the data evaluates the variation in form and in dimension separately. The shape change is defined by Euclidean Distance Matrix Analysis (EDMA) and Bootstrap analysis. The computerized method allows orthodontists and researches to evaluate the variation in dimension and form of the dental arch in un-treated subjects and-or orthodontic patients over time. After the analysis of a large sample of patients or subjects, information concerning changes in dental arch dimension and form can be added to previous studies of other authors, distinguishing variation during and after orthodontic treatment, during growth or aging.

  3. The randomized shortened dental arch study: tooth loss.

    PubMed

    Walter, M H; Weber, A; Marré, B; Gitt, I; Gerss, J; Hannak, W; Hartmann, S; Heydecke, G; Huppertz, J; Jahn, F; Ludwig, A; Mundt, T; Kern, M; Klein, V; Pospiech, P; Stumbaum, M; Wolfart, S; Wöstmann, B; Busche, E; Böning, K; Luthardt, R G

    2010-08-01

    The evidence concerning the management of shortened dental arch (SDA) cases is sparse. This multi-center study was aimed at generating data on outcomes and survival rates for two common treatments, removable dental prostheses (RDP) for molar replacement or no replacement (SDA). The hypothesis was that the treatments lead to different incidences of tooth loss. We included 215 patients with complete molar loss in one jaw. Molars were either replaced by RDP or not replaced, according to the SDA concept. First tooth loss after treatment was the primary outcome measure. This event occurred in 13 patients in the RDP group and nine patients in the SDA group. The respective Kaplan-Meier survival rates at 38 months were 0.83 (95% CI: 0.74-0.91) in the RDP group and 0.86 (95% CI: 0.78-0.95) in the SDA group, the difference being non-significant.

  4. Simple Way of Recording Dental Arch Forms

    PubMed Central

    Ratre, Ram Kishore; Jain, Sandhya; Chandki, Rita

    2015-01-01

    Like finger prints each individual has a unique dental arch form design. Recording patient’s dental arch form may be required in various fields in dentistry be it longitudinal studies for evaluating growth, forensic dentistry and most importantly in orthodontic practice for fabricating arch wires for individual patients. An easy and practical method to obtain individual arch form for each patient is explained. PMID:25954726

  5. Dental Arch Wire

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Straightening teeth is an arduous process requiring months, often years, of applying corrective pressure by means of arch wires-better known as brace-which may have to be changed several times in the course of treatment. A new method has been developed by Dr. George Andreasen, orthodontist and dental scientist at the University of Iowa. The key is a new type of arch wire material, called Nitinol, with exceptional elasticity which helps reduce the required number of brace changes. An alloy of nickel and titanium, Nitinol was originally developed for aerospace applications by the Naval Ordnance Laboratory, now the Naval Surface Weapons Laboratory, White Oaks, Maryland. NASA subsequently conducted additional research on the properties of Nitinol and on procedures for processing the metal.

  6. The randomized shortened dental arch study: temporomandibular disorder pain.

    PubMed

    Reissmann, Daniel R; Heydecke, Guido; Schierz, Oliver; Marré, Birgit; Wolfart, Stefan; Strub, Joerg R; Stark, Helmut; Pospiech, Peter; Mundt, Torsten; Hannak, Wolfgang; Hartmann, Sinsa; Wöstmann, Bernd; Luthardt, Ralph G; Böning, Klaus W; Kern, Matthias; Walter, Michael H

    2014-12-01

    The aim of this multi-center, randomized controlled trial was to assess the impact of missing posterior support on the risk for temporomandibular disorder (TMD) pain by comparing patients with either shortened dental arches (SDA) or molar replacement by removable dental prostheses (RDP). A sample of 215 patients with bilateral molar loss in at least one jaw was consecutively recruited in 14 prosthodontic departments of dental schools in Germany. Of the initial sample, 152 patients (mean age: 59.7 years; 53.9 % female) received randomly allocated interventions (SDA: n = 71; RDP: n = 81). Presence of TMD pain was assessed using patients' self-reports and was verified by physical examination and by pain intensity, as the mean of current pain, worst pain, and average pain in the last 6 months, with 10-point ordinal rating scales. Assessments were performed before treatment and at follow-ups until 60 months after treatment. Impact of interventions on TMD risk and pain intensity was computed by applying logistic and linear random-intercept models. Tooth replacement (RDP) did not significantly change the risk for self-reported (odds ratio [OR]: 1.1; confidence interval [CI]: 0.4 to 3.4) or clinically verified (OR: 0.7; CI: 0.1 to 4.3) TMD pain compared to no tooth replacement (SDA). Mean characteristic pain intensity was virtually identical in both groups (Coeff: 0.01; CI: -0.30 to 0.32). Retaining or preservation of an SDA is not a major risk factor for TMD pain over the course of 5 years when compared to molar replacement with RPDs. Seemingly, missing molars do not have to be replaced in order to prevent TMD pain.

  7. Longitudinal study of dental arch relationships in Australian aboriginals with reference to alternate intercuspation.

    PubMed

    Brown, T; Abbott, A H; Burgess, V B

    1987-01-01

    The patterns of age change in dental arch breadths and depths were studied longitudinally in Australian Aboriginals, 92 males and 68 females. Three types of change in relative arch dimensions were recognized: a divergent pattern in which the differences between maxillary and mandibular dimensions increased with age, a convergent pattern in which the differences decreased, and a parallel pattern in which the arch differences remained metrically stable. The feature that best distinguished the Aboriginals from Caucasian groups was the high frequency of subjects, 71% of males and 40% of females, who showed a divergent growth pattern. The association between divergent growth in arch breadths and the development of alternate intercuspation, which is characterized by an inability to occlude the teeth on both sides of the arch at the same time, is discussed.

  8. A longitudinal study of dental arch morphology in children with the syndrome of Crouzon or Apert.

    PubMed

    Reitsma, Jacobus H; Elmi, Poejan; Ongkosuwito, Edwin M; Buschang, Peter H; Prahl-Andersen, Birte

    2013-08-01

    The aim of this study was to compare changes in dental arch morphology between patients with Crouzon syndrome or Apert syndrome and controls. Children between 4 and 14 yr of age with Crouzon syndrome (n = 40) or Apert syndrome (n = 28) were compared with non-syndromic controls (n = 457) in terms of arch widths, depths, and length dimensions. Multilevel statistical modeling techniques were used to evaluate changes over time. Dental arch dimensions were found to be smaller in patients with Crouzon syndrome or Apert syndrome compared with control subjects. Maxillary intercanine width for patients with Apert syndrome were increased, whilst other arch width variables showed no change. Patients with Crouzon syndrome showed increases in maxillary intercanine width, whilst intermolar width showed no change over time. Dental arch dimensions in syndromic patients were thus found to be consistently smaller than in control subjects between 4 and 14 yr of age, implying that patients with Crouzon syndrome and Apert syndrome had a diminished growth potential. © 2013 Eur J Oral Sci.

  9. Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

    PubMed Central

    D’Souza, Ivor M; Kumar, H. C. Kiran; Shetty, K. Sadashiva

    2015-01-01

    Introduction: Transverse deficiency of the maxilla is a common clinical problem in orthodontics and dentofacial orthopedics. Transverse maxillary deficiency, isolated or associated with other dentofacial deformities, results in esthetic and functional impairment giving rise to several clinical manifestations such as asymmetrical facial growth, positional and functional mandibular deviations, altered dentofacial esthetics, adverse periodontal responses, unstable dental tipping, and other functional problems. Orthopedic maxillary expansion is the preferred treatment approach to increase the maxillary transverse dimension in young patients by splitting of the mid palatal suture. This orthopedic procedure has lately been subject of renewed interest in orthodontic treatment mechanics because of its potential for increasing arch perimeter to alleviate crowding in the maxillary arch without adversely affecting facial profile. Hence, the present investigation was conducted to establish a correlation between transverse expansion and changes in the arch perimeter, arch width and arch length. Methods: For this purpose, 10 subjects (five males, five females) were selected who had been treated by rapid maxillary expansion (RME) using hyrax rapid palatal expander followed by fixed mechanotherapy (PEA). Pretreatment (T1), postexpansion (T2), and posttreatment (T3) dental models were compared for dental changes brought about by RME treatment and its stability at the end of fixed mechanotherapy. After model measurements were made, the changes between T1–T2, T2–T3 and T1–T3 were determined for each patient. The mean difference between T1–T2, T2–T3 and T1–T3 were compared to assess the effects of RME on dental arch measurements. Results are expressed as mean ± standard deviation and are compared by repeated measures analysis of variance followed by a post-hoc test. Arch perimeter changes are correlated with changes in arch widths at the canine, premolar and molar regions

  10. Dental arch dimensions in the mixed dentition: a study of Brazilian children from 9 to 12 years of age

    PubMed Central

    LOULY, Fabiane; NOUER, Paulo Roberto Aranha; JANSON, Guilherme; PINZAN, Arnaldo

    2011-01-01

    Objective This study evaluated dental arch dimensional changes of Brazilian children. Material and methods Dental casts were taken from 66 children (29 males; 37 females) with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dimensions were taken by one examiner using the Korkhaus’ compass and a digital pachymeter. ANOVA test was applied to compare the arch dimensions at the different ages and the t-test was used to compare the arch dimensions of male and female subjects. Arch forms were compared by means of chi-square tests. Results Only the maxillary anterior segment length showed a statistically significant increase from 10 to 12 years of age. Males had a significantly larger maxillary depth than females at the age range evaluated. The predominant dental arch form found was elliptical. Conclusion In the studied age range, anterior maxillary length increased from 10 to 12 years of age, males had larger maxillary depth than females and the predominant arch form was elliptical. PMID:21552719

  11. Heritability estimates of dental arch parameters in Lithuanian twins.

    PubMed

    Švalkauskienė, Vilma; Šmigelskas, Kastytis; Šalomskienė, Loreta; Andriuškevičiūtė, Irena; Šalomskienė, Aurelija; Vasiliauskas, Arūnas; Šidlauskas, Antanas

    2015-01-01

    The genetic influence on dental arch morphology may be country-specific, thus it is reasonable to check the estimates of genetics across different populations. The purpose of this study was to evaluate the heredity of dental arch morphology in the sample of Lithuanian twins with accurate zygosity determination. The study sample consisted of digital dental models of 40 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs. The estimates of heritability (h(2)) for dental arch breadth and length were calculated. All dental arch breadths and lengths were statistically significantly larger in men than in women. Arch length differences between genders were less expressed than largest breadth differences. In the upper jaw the largest genetic effect was found on the arch breadth between lateral incisors. The heritability of dental arch length demonstrated similar differences between upper and lower jaw with mandible dental arch length being more genetically determined. The largest genetic impact was found on the upper dental arch breadth between lateral incisors. Similar, but lower heritability is inherent for canines and first premolars of the upper jaw and first premolars of the lower jaw. It also can be noted, that arch breadths between posterior teeth show lower heritability estimates than between anterior teeth on both jaws. The dental arch in the upper jaw has more expressed genetic component than in the lower jaw.

  12. Maxillary dental arch form related to voice classification: a pilot study.

    PubMed

    Marunick, M T; Menaldi, C J

    2000-03-01

    This pilot study evaluated maxillary dental arch form dimensions and volume to determine if these parameters could be predictors for or related to voice classification. Nine white female professional singers ranging in age from 26 years to 53 years were studied. A maxillary dental impression and stone dental casts were made using standard dental procedures. Measurements were made from 10 points on each cast to determine the depth of the palate measured from first molar (depth A) and from first bicuspid (depth B), the width measured from cuspid-to-cuspid (width A) and from second molar to second molar (width B), and the length of the palate. An impression of the palatal arch of each cast was made to determine the volume of the palate using fluid displacement methods. Audio recordings were made for each subject, and based on speaking fundamental frequency, spectral analysis, voice profile, and tessitura confirmation, the actual voice classification of each subject in soprano, mezzo, and alto was achieved. Correlation and discriminant analysis tests were performed on the data. The discriminant analysis revealed that no single measurement is a predictor for voice classification. However, the discriminant analysis applied to the predictors depth A, depth B, and volume gives optimal results, ie, each subject was classified in her true group.

  13. Morphological and Dimensional Characteristics of Dental Arch among Tribal and Non-tribal Population of Central India: A Comparative Study

    PubMed Central

    Yadav, Naveen S; Saxena, Vrinda; Vyas, Rajesh; Sharma, Rohit; Sharva, Vijayta; Dwivedi, Ashish; Jain, Manish

    2014-01-01

    Background: Differences in the dental arch among Bhil Aboriginals were investigated and compared with non-tribal individuals residing in a tribal zone of Central India. Plaster models (120) were made with the help of alginate impression of tribal adults as well as non-tribal adults residing in the same area. The supposition as aboriginals being primitive due to dietary practices maxillary arch size and mandibular arch size is distended in comparison to the non-tribal population as adaptation of soft refined diet has disrupted the growth of the jaws. Hence, an attempt was made to evaluate the arch widths of tribal population and to associate it with non-tribe population in the same area of Central India. Materials and Methods: Difference in morphology and dimension of the maxillary and mandibular arches was aimed at Bhil tribes as well as non-tribal residents of tribe rich zone of Central India. The study was steered amid 120 individuals both tribal and non-tribe equally around 60 each through a well-organized out-reach program intermittently. Study models were made of dental arches of all participants. All measurements of the arch dimension were patent on the study casts using an electronic digital sliding caliper. Pair t-test was applied by using SPSS software version-19.0. Results: In the maxillary arch, on appraisal the non-tribal and Bhil tribe’s subjects, it showed a statistically significant difference in inter-incisor width (2.95 mm), inter-canine width (2.60 mm), arch depth (3.25 mm). While inter premolar width (0.20 mm) and inter molar width (0.80 mm) anterior arch length (0.60 mm), and posterior arch length (0.10 mm) showed statistically not significant difference between non-tribal population and Bhil tribe subjects. In the mandibular arch, it showed a statistically significant difference in inter-canine width (1.00 mm). Although, inter-incisor width (0.72 mm), inter-molar width (0.80 mm), arch depth (0.90 mm), anterior arch length (0.30 mm), posterior

  14. Comparison of maxillary and mandibular dental arch forms by studying Fourier series developed from mathematically estimated dentitions.

    PubMed

    Mikami, Hiroko; Nakatsuka, Michiko; Iwai, Yasutomo

    2010-11-01

    We conducted a Fourier analysis on data obtained using correlation and principal component analyses of parallel-standardized dental study models; both maxillary and mandibular dental arches were predominantly round square in shape. The present study compared and determined the contribution ratio and reproducible coefficients of amplitudes (factors affecting dental arch forms), and demonstrated that the 1st to 4th and the 1st to 6th Fourier harmonics reproduced maxillary and mandibular dental arch forms, respectively. The correlation analyses of the constant term and amplitudes demonstrated that significant differences in the 2nd harmonic amplitude was strongly correlated with the curvature of anterior teeth and the length-to-width ratio in maxillary dentitions. By comparison of the constant term and amplitudes between different arch types, we did not observe significant differences in the constant term and the 1st amplitude of maxillary dentitions and in constant term and all amplitudes of mandibular dentitions. Nevertheless, the study revealed high contribution ratios of the 1st (in mandibular dentitions) and the 2nd (in maxillary dentitions) amplitudes essentially affecting the reproducibility of arch forms. The 1st amplitudes demonstrated a bow-like arrangement of all arch types, while the 2nd amplitudes adjusted the anterior-teeth curvature and in particular demonstrated the length-to-width ratio of maxillary dentitions. The 3rd and the 4th amplitudes were also determinants of the anterior-teeth curvature of maxillary dentitions. The 6th amplitude was necessary for reproduction, but showed no difference between varying mandibular dental arch types. Collectively, we conclude that the establishment of a Fourier series significantly reproduced maxillary but not mandibular dental arch forms.

  15. [Cross-sectional study of the evolution of the primary dentition: shape of dental arches, overjet and overbite].

    PubMed

    de Castro, Liana Amado; Modesto, Adriana; Vianna, Roberto; Soviero, Vera Lígia Mendes

    2002-01-01

    The aim of this study was to evaluate the characteristics (shape of dental arches, overjet and overbite) of the primary dentition of 6- to 39-month-old children from four nurseries of Rio de Janeiro, Brazil, and to associate them to gender and dentition phase. It was observed that 68.6% of the children presented round upper arch, while 31.4% had triangular upper arch; 92% of the children presented U-shaped lower arch and 8% had square-shaped lower arch. Moderate overjet was observed in 38.3% of the children, and slight overjet, in 30.3%. Severe (26.6%) and negative (25.5%) overbites were the most prevalent modalities of that condition. There was no association between gender and the studied characteristics. There was statistically significant association between the dentition phase and the shape of the arch, overjet and overbite (p < 0.001, chi-square test). It was possible to observe, in the present study, that early signs of malocclusions appeared when first primary molars erupted, as the posterior vertical dimension of occlusion increased. It was, thus, verified that early signs of malocclusions appear as the primary dentition develops. It is very important that the first dental visit occur during the first year of age, since it allows the pediatric dentist to prevent or carry out an early diagnosis of malocclusions in the primary dentition.

  16. The Randomized Shortened Dental Arch study (RaSDA): design and protocol.

    PubMed

    Luthardt, Ralph G; Marré, Birgit; Heinecke, Achim; Gerss, Joachim; Aggstaller, Hans; Busche, Eckhard; Dressler, Paul; Gitt, Ingrid; Hannak, Wolfgang; Hartmann, Sinsa; Heydecke, Guido; Jahn, Florentine; Kern, Matthias; Mundt, Torsten; Pospiech, Peter; Stark, Helmut; Wöstmann, Bernd; Walter, Michael H

    2010-02-19

    Various treatment options for the prosthetic treatment of jaws where all molars are lost are under discussion. Besides the placement of implants, two main treatment types can be distinguished: replacement of the missing molars with removable dental prostheses and non-replacement of the molars, i.e. preservation of the shortened dental arch. Evidence is lacking regarding the long-term outcome and the clinical performance of these approaches. High treatment costs and the long time required for the treatment impede respective clinical trials. This 14-center randomized controlled investigator-initiated trial is ongoing. Last patient out will be in 2010. Patients over 35 years of age with all molars missing in one jaw and with at least both canines and one premolar left on each side were eligible. One group received a treatment with removable dental prostheses for molar replacement (treatment A). The other group received a treatment limited to the replacement of all missing anterior and premolar teeth using fixed bridges (treatment B). A pilot trial with 32 patients was carried out. Two hundred and fifteen patients were enrolled in the main trial where 109 patients were randomized for treatment A and 106 for treatment B. The primary outcome measure is further tooth loss during the 5-year follow-up. The secondary outcome measures encompassed clinical, technical and subjective variables. The study is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG WA 831/2-1, 2-2, 2-3, 2-4, 2-5). The particular value of this trial is the adaptation of common design components to the very specific features of complex dental prosthetic treatments. The pilot trial proved to be indispensable because it led to a number of adjustments in the study protocol that considerably improved the practicability. The expected results are of high clinical relevance and will show the efficacy of two common treatment approaches in terms of oral health. An array of secondary

  17. The randomized shortened dental arch study (RaSDA): design and protocol

    PubMed Central

    2010-01-01

    Background Various treatment options for the prosthetic treatment of jaws where all molars are lost are under discussion. Besides the placement of implants, two main treatment types can be distinguished: replacement of the missing molars with removable dental prostheses and non-replacement of the molars, i.e. preservation of the shortened dental arch. Evidence is lacking regarding the long-term outcome and the clinical performance of these approaches. High treatment costs and the long time required for the treatment impede respective clinical trials. Methods/design This 14-center randomized controlled investigator-initiated trial is ongoing. Last patient out will be in 2010. Patients over 35 years of age with all molars missing in one jaw and with at least both canines and one premolar left on each side were eligible. One group received a treatment with removable dental prostheses for molar replacement (treatment A). The other group received a treatment limited to the replacement of all missing anterior and premolar teeth using fixed bridges (treatment B). A pilot trial with 32 patients was carried out. Two hundred and fifteen patients were enrolled in the main trial where 109 patients were randomized for treatment A and 106 for treatment B. The primary outcome measure is further tooth loss during the 5-year follow-up. The secondary outcome measures encompassed clinical, technical and subjective variables. The study is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG WA 831/2-1, 2-2, 2-3, 2-4, 2-5). Discussion The particular value of this trial is the adaptation of common design components to the very specific features of complex dental prosthetic treatments. The pilot trial proved to be indispensable because it led to a number of adjustments in the study protocol that considerably improved the practicability. The expected results are of high clinical relevance and will show the efficacy of two common treatment approaches in terms of

  18. The randomized shortened dental arch study: tooth loss over five years.

    PubMed

    Walter, M H; Hannak, W; Kern, M; Mundt, T; Gernet, W; Weber, A; Wöstmann, B; Stark, H; Werner, D; Hartmann, S; Range, U; Jahn, F; Passia, N; Pospiech, P; Mitov, G; Brückner, J; Wolfart, S; Busche, E; Luthardt, R G; Heydecke, G; Marré, B

    2013-04-01

    The study was designed to provide clinical outcome data for two treatments of the shortened dental arch (SDA). In a multicenter randomized controlled clinical trial, patients with complete molar loss in one jaw were provided with either a partial removable dental prosthesis (PRDP) retained with precision attachments or treated according to the SDA concept preserving or restoring a premolar occlusion. No implants were placed. The primary outcome was tooth loss. Of 152 treated patients, 132 patients reached the 5-year examination. Over 5 years, 38 patients experienced tooth loss. For the primary outcome tooth loss, the Kaplan-Meier survival rates at 5 years were 0.74 (95% CI 0.64, 0.84) in the PRDP group and 0.74 (95% CI 0.63, 0.85) in the SDA group. For tooth loss in the study jaw, the survival rates at 5 years were 0.88 (95% CI 0.80, 0.95) in the PRDP group and 0.84 (95% CI 0.74, 0.93) in the SDA group. The differences were not significant. No Cox regression models of appropriate fit explaining tooth loss on the patient level could be found. The overall treatment goals of a sustainable oral rehabilitation and the avoidance of further tooth loss over longer periods were not reliably achievable. The influence of the type of prosthetic treatment on tooth loss might have been overestimated. Regarding our results, the patient's view will gain even more importance in the clinical decision between removable and fixed restorations in SDAs.

  19. Masticatory efficiency of shortened dental arch subjects with removable partial denture: A comparative study.

    PubMed

    Omo, J O; Sede, M A; Esan, T A

    2017-04-01

    The objective of this study was to compare the masticatory efficiency in subjects with shortened dental arch (SDA) before and after restoration with removable partial denture (RPD). This was a prospective study carried out on 36 consecutive patients. The subjects were asked to chew 5 g of a measured portion of fresh raw carrot for 20 specified numbers of strokes. The raw carrot was recovered into a cup and strained through a standard mesh sieve of 5 mm by 1 mm, it was air dried for 30 min and weighed with FEM digital series weighing scale. The masticatory performance ratio was then determined. The age range of the subjects was 34-64 years with the mean age being 52.2 ± 8.2 years. The difference between the total masticatory performance score at the post- and pre-treatment phases was statistically significant (P = 0.001). The improvement in masticatory performance was marked among the younger age groups (P = 0.001), unilateral free end saddle subjects (P = 0.001), and among the male gender (P < 0.05). Masticatory performance improved with the provision of RPD. However, the improvement was marked among the younger age groups, unilateral free end saddle subjects, and the male gender; thereby supporting the need for RPDs in patients with SDA.

  20. Places in the dental arch that show a greater variability in tooth number, shape and position--a prevalence study.

    PubMed

    Primožič, Jasmina; Farčnik, Franc; Ovsenik, Maja

    2012-06-01

    The aim of this study was to assess the frequency of variations in tooth number, shape and position in the dental arch to determine if there are parts of the dental arch that show a higher prevalence of tooth variability. 198 randomly selected Caucasian subjects (93 females, 105 males) aged between 10.0 and 24.5 years (mean age 14.15, SD 2.34 years) were included. A total of 5544 teeth were examined and dental anomalies of tooth number, shape and position (oral teeth positions and teeth rotations greater than 45°) were recorded. 18.68 per cent of the subjects had one or more unerupted teeth. Aplasia as the cause of uneruption was found in 12.12 per cent of the subjects, statistically significantly more frequently in females than males (Fisher test, p < 0.05). Tooth shape anomalies were found in 6.57 per cent of the sample, more frequently in males than females (Fisher test, p < 0.05). Oral position of one or more teeth was found in 47.98 per cent of the sample, whilst rotations greater than 45° were found in 15.66 per cent, with no statistically significant differences between females and males. One or more of the observed dental anomalies were found in several tooth types, however all the observed dental anomalies were found only in second premolars and in upper lateral incisor. According to the results of this study, it seems that some places in the dental arch show a greater variability in terms of tooth number, shape and position. This could be a result of genetic and environmental influences during odontogenesis or a result of evolutionary trends. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Motion planning and synchronized control of the dental arch generator of the tooth-arrangement robot.

    PubMed

    Jiang, Jin-Gang; Zhang, Yong-De

    2013-03-01

    The traditional, manual method of reproducing the dental arch form is prone to numerous random errors caused by human factors. The purpose of this study was to investigate the automatic acquisition of the dental arch and implement the motion planning and synchronized control of the dental arch generator of the multi-manipulator tooth-arrangement robot for use in full denture manufacture. First, the mathematical model of the dental arch generator was derived. Then the kinematics and control point position of the dental arch generator of the tooth arrangement robot were calculated and motion planning of each control point was analysed. A hardware control scheme is presented, based on the industrial personal computer and control card PC6401. In order to gain single-axis, precise control of the dental arch generator, we studied the control pulse realization of high-resolution timing. Real-time, closed-loop, synchronous control was applied to the dental arch generator. Experimental control of the dental arch generator and preliminary tooth arrangement were gained by using the multi-manipulator tooth-arrangement robotic system. The dental arch generator can automatically generate a dental arch to fit a patient according to the patient's arch parameters. Repeated positioning accuracy is 0.12 mm for the slipways that drive the dental arch generator. The maximum value of single-point error is 1.83 mm, while the arc-width direction (x axis) is -33.29 mm. A novel system that generates the dental arch has been developed. The traditional method of manually determining the dental arch may soon be replaced by a robot to assist in generating a more individual dental arch. The system can be used to fabricate full dentures and bend orthodontic wires. Copyright © 2012 John Wiley & Sons, Ltd.

  2. Distribution of dental plaque and gingivitis within the dental arches.

    PubMed

    Sreenivasan, Prem K; Prasad, Kakarla V V

    2017-10-01

    Objective The natural accumulation of supragingival plaque on surfaces of human teeth is associated with gingival inflammation and the initiation of common oral diseases. This study evaluated the distribution of dental plaque and gingivitis scores within the dental arches after prophylaxis. Methods Adult subjects from the Dharwad, India area representing the general population who provided written informed consent were scheduled for screening. Healthy subjects over the age of 18 years, not currently requiring any medical or dental care, and presenting with a complement of at least 20 natural teeth were recruited for this parallel design study. Enrolled subjects (n = 41) underwent oral examinations for dental plaque (PI) and gingivitis (GI) using the Turesky modification of the Quigley-Hein and the Löe-Silness Index, respectively, at the baseline visit, followed by a whole mouth dental prophylaxis. Subjects were given fluoride toothpaste for twice daily oral hygiene for the next 30 days. Subjects were recalled on days 15 and 30 for PI and GI examinations identical to baseline. Results Analyses indicated that mean scores for PI and GI on either arch and the whole mouth were higher than 2 and 1, respectively, during all examinations. Anterior surfaces consistently exhibited lower PI scores than posterior regions of either arch, or the entire dentition. Regional GI differences within the dentition were similar to PI scores, with lower scores on anterior than posterior teeth. Prophylaxis reduced both the frequency and mean scores of both PI and GI, irrespective of arch, with lower scores observed on anterior than posterior regions during all recall visits. Molar and lingual regions consistently exhibited higher PI and GI scores compared with anterior surfaces. At all examinations, mean scores for both plaque and gingivitis were higher on approximal vestibular than mid-vestibular surfaces. Conclusions Differences observed in PI and GI within the dentition have

  3. Experience from Classroom Teaching to Clinical Practice Regarding Shortened Dental Arch (SDA) Concept Among Dentists - A Questionnaire Study.

    PubMed

    Gupta, Ritu; Malhi, Ravneet; Patthi, Basavaraj; Singla, Ashish; Janakiram, Chandrasheker; Pandita, Venisha; Prasad, Monika; Kumar, Jishnu Krishna

    2016-12-01

    Periodontal disease and dental caries are the common oral conditions which cause loss of teeth, mostly molars. This further leads to Shortening of Dental Arch and Shortened Dental Arch (SDA) concept provides the overall requirements of functional dentition at reduced cost without compromising the health. The aim of the present study was to assess the Knowledge, Attitude and Practices (KAP) towards SDA concept among dentists of Ghaziabad city (Uttar Pradesh, India). A cross-sectional study was conducted among 514 dentists working as academicians or clinicians or both. KAP questionnaire consisting of questions related to SDA concept was distributed to them. Data were analyzed using Statistical Package for Social Sciences (SPSS) 18.0 (SPSS Inc., Chicago, IL, USA) and descriptive and analytical tests, including mean, standard deviation, and Chi square test were used. Of the 514 dentists, only 493 dentists responded to the questionnaire, generating the response rate of 95.5%. Only 113 (22.9%) had knowledge about this concept. Clinicians were found to have more knowledge regarding the SDA concept (p<0.05). Also years of experience and level of knowledge among dentists regarding SDA was found to be statistically significant (p<0.05). The study showed lack of knowledge regarding SDA concept among dentists and also only few dentists practice the SDA concept on their patients. If used judiciously the SDA concept can serve as a cost effective and functionally oriented approach in clinical management of patients.

  4. Experience from Classroom Teaching to Clinical Practice Regarding Shortened Dental Arch (SDA) Concept Among Dentists – A Questionnaire Study

    PubMed Central

    Malhi, Ravneet; Patthi, Basavaraj; Singla, Ashish; Janakiram, Chandrasheker; Pandita, Venisha; Prasad, Monika; Kumar, Jishnu Krishna

    2016-01-01

    Introduction Periodontal disease and dental caries are the common oral conditions which cause loss of teeth, mostly molars. This further leads to Shortening of Dental Arch and Shortened Dental Arch (SDA) concept provides the overall requirements of functional dentition at reduced cost without compromising the health. Aim The aim of the present study was to assess the Knowledge, Attitude and Practices (KAP) towards SDA concept among dentists of Ghaziabad city (Uttar Pradesh, India). Materials and Methods A cross-sectional study was conducted among 514 dentists working as academicians or clinicians or both. KAP questionnaire consisting of questions related to SDA concept was distributed to them. Data were analyzed using Statistical Package for Social Sciences (SPSS) 18.0 (SPSS Inc., Chicago, IL, USA) and descriptive and analytical tests, including mean, standard deviation, and Chi square test were used. Results Of the 514 dentists, only 493 dentists responded to the questionnaire, generating the response rate of 95.5%. Only 113 (22.9%) had knowledge about this concept. Clinicians were found to have more knowledge regarding the SDA concept (p<0.05). Also years of experience and level of knowledge among dentists regarding SDA was found to be statistically significant (p<0.05). Conclusion The study showed lack of knowledge regarding SDA concept among dentists and also only few dentists practice the SDA concept on their patients. If used judiciously the SDA concept can serve as a cost effective and functionally oriented approach in clinical management of patients. PMID:28208999

  5. Timing of hard palate closure and dental arch relationships in unilateral cleft lip and palate patients: a mixed-longitudinal study.

    PubMed

    Noverraz, A E; Kuijpers-Jagtman, A M; Mars, M; van't Hof, M A

    1993-07-01

    In a mixed longitudinal study, dental arch relationships of 88 consecutive UCLP patients treated at the Nijmegen Cleft Palate Centre were evaluated using the Goslon Yardstick. On the basis of timing of hard palate closure, the patients were divided into four groups. Mean age of hard palate closure the patients were divided into four groups. Mean age of hard palate closure in group A (n = 18) was 1.5 years, in group B (n = 26) 4.6 years and in group C (n = 18) 9.4 years. In group D (n = 26, no patient older than 10 years) the hard palate was still open. Four stages of dental development were distinguished; deciduous dentition, early mixed dentition, late mixed dentition and permanent dentition. Reproducibility of scoring with the Goslon Yardstick was good for all stages of dental development. No differences in dental arch relationships were found between the four groups. In 86% of the cases, the dental arch relationships of UCLP patients treated in Nijmegen were acceptable. Pharyngeal flap surgery had minor unfavorable effects on dental arch relationships.

  6. Determining shapes and dimensions of dental arches for the use of straight-wire arches in lingual technique

    PubMed Central

    Kairalla, Silvana Allegrini; Scuzzo, Giuseppe; Triviño, Tarcila; Velasco, Leandro; Lombardo, Luca; Paranhos, Luiz Renato

    2014-01-01

    INTRODUCTION: This study aims to determine the shape and dimension of dental arches from a lingual perspective, and determine shape and size of a straight archwire used for lingual Orthodontics. METHODS: The study sample comprised 70 Caucasian Brazilian individuals with normal occlusion and at least four of Andrew's six keys. Maxillary and mandibular dental casts were digitized (3D) and the images were analyzed by Delcam Power SHAPET 2010 software. Landmarks on the lingual surface of teeth were selected and 14 measurements were calculated to determine the shape and size of dental arches. RESULTS: Shapiro-Wilk test determined small arch shape by means of 25th percentile (P25%) - an average percentile for the medium arch; and a large one determined by means of 75th percentile (P75%). T-test revealed differences between males and females in the size of 12 dental arches. CONCLUSION: The straight-wire arch shape used in the lingual straight wire technique is a parabolic-shaped arch, slightly flattened on its anterior portion. Due to similarity among dental arch sizes shown by males and females, a more simplified diagram chart was designed. PMID:25715725

  7. Age changes in dental arch dimensions of Australian Aboriginals.

    PubMed

    Brown, T; Abbott, A H; Burgess, V B

    1983-11-01

    Breadths and depths of the dental arches were measured from standardized photographs of serial casts of Australian Aboriginals enrolled in a longitudinal growth study. The data were obtained from 1161 sets of casts representing 111 boys and 86 girls ranging in age from 6 to 19 years. Age changes in the arch dimensions conformed to previously described patterns in Caucasian children, namely, an increase in breadth and a decrease in depth. Corresponding dimensions and dimensional changes in the maxilla and mandible were strongly correlated, but breadth and depth changes were relatively independent. The disparity in size between arches increased with age, particularly in the breadth dimension of boys. Marked disparity in arch breadths characterizes an occlusal feature of this population that has been termed alternate intercuspation.

  8. Roles of different areas of palatine bone denudation on growth and development of the maxilla and dental arch: an experimental study.

    PubMed

    Meng, Tian; Shi, Bing; Huang, Xu; Zheng, Qian; Wang, Yan; Wu, Min; Lu, Yong; Li, Sheng

    2007-03-01

    This study was designed to explore the relationship of the growth of the maxilla and dental arch with different sizes of the denudation area on the hard palate. We tested the hypothesis that different sizes of denudation areas on the hard palate following palatoplasty would significantly influence the growth of the maxilla and dental arch differently. Fifty-one three-week-old Sprague-Dawley male rats were randomly divided into a control group and 3 experimental groups. In the three experimental groups, bilateral palatal mucoperiosteum was excised to three different proportions, i.e. one-quarter, one-half and three-quarters of the palate. Then, the animals were sequentially injected weekly with different fluorescent markers alternately. Three in each group were sacrificed randomly every two weeks with maxilla dissected following injections. The widths of the maxilla and dental arch were measured and the fluorescent labeling investigated at different phases. The results showed that the growth of the maxilla and dental arch here was inversely correlated with the area of denuded bone on palate. Therefore, our data may provide references for optimal treatment of cleft palate.

  9. Dental arch dimensional changes after adenotonsillectomy in prepubertal children.

    PubMed

    Petraccone Caixeta, Anna Cristina; Andrade, Ildeu; Bahia Junqueira Pereira, Tatiana; Franco, Letícia Paiva; Becker, Helena Maria Gonçalves; Souki, Bernardo Quiroga

    2014-04-01

    The purposes of this study were to investigate the dental arch changes after adenotonsillectomies in prepubertal children and to compare the dental arch dimensions of mouth-breathing and nasal-breathing children. The sample included 49 prepubertal severely obstructed mouth-breathing children and 46 prepubertal nasal-breathing children. Twenty-four of the 49 mouth-breathing children had an adenotonsillectomy and composed the adenotonsillectomy subgroup. The 25 children in whom the mouth-breathing pattern was unchanged during the 1-year study period composed the control subgroup. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. After airway clearance, the adenotonsillectomy group showed a significant maxillary transverse width gain compared with the control subgroup. The control subgroup showed a significant deepening of the palatal height when compared with the adenotonsillectomy subgroup after 1 year. The adenotonsillectomy subgroup had a significantly different pattern of arch development compared with the untreated controls. After adenotonsillectomy, the mouth-breathing children showed greater maxillary transverse development than did the controls. The palatal vault deepened in the untreated children. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  10. Mathematical definition of the shape of dental arches in human permanent healthy dentitions.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G

    1994-08-01

    Dental arch shape was studied in 50 men and 45 women aged 20-27 years with sound dentitions. Maxillary and mandibular arches were reconstructed by a fourth-order polynomial and a 'mixed' elliptical (anterior teeth), plus parabolic (post-canine teeth) interpolation of buccal cusp tips (central incisor to second molar). The maxillary arch resulted wider than the mandibular arch regardless of gender. Gender differences were found especially in the maxillary arch, where they reflect more a size discrepancy than a shape difference. The polynomial interpolation allowed the evaluation of arch asymmetry, which resulted negligible in all the subjects. The elliptical plus parabolic interpolation gave mean plots which were well superimposable to the ones obtained by the polynomial interpolation. These curves are geometrically simple and can be used for the mathematical description of dental arch shape in non-patient subjects. Moreover, they allow separate analysis of teeth with a different functional meaning.

  11. Alveolar and dental arch morphology in Angle Class II division 2 malocclusion: a comparative study.

    PubMed

    Bălan, Raluca Adriana; Popa, George; Biţă, Romina; Fabricky, Mihai; Jivănescu, Anca; Bratu, Dana Cristina

    2014-01-01

    The aim of this study was to analyze the dental and alveolar intercanine, interpremolar and intermolar widths in patients with Class II/2 malocclusion and to compare the data with a patient group with normal occlusion and also with a patient group with Class II/1 malocclusion. The study was conducted on 140 untreated patients with permanent dentition, aged 16 to 25 years, which were divided into three groups, according to Angle's classification of occlusion. The measurements of the dento-alveolar intercanine, interpremolar and intermolar widths were made on virtual study models, scanned using an optical 3D scanner. The unpaired (Student's) t-test was used to determine whether there were any significant differences between the Class II/2 and Class I groups and between Class II/2 and Class II/1 groups, respectively (p<0.05). Significant differences were found between Class II/2 and Class II/1 groups in the maxillary and mandibular intercanine widths. Comparing the Class II/2 and Class I groups, significant differences were found in the mandibular intercanine width, in the maxillary and mandibular interpremolar widths and also in the maxillary and mandibular intercanine and interpremolar alveolar widths. The maxillary and mandibular interpremolar widths and the intercanine and interpremolar alveolar widths were larger, while the mandibular intercanine width was shorter in the Class I group than in the Class II division 2 group. The mandibular intercanine width was longer and the maxillary intercanine width was shorter in the Class II division 1 group compared to the Class II division 2 group.

  12. Influence of posterior dental arch length on brain activity during chewing in patients with mandibular distal extension removable partial dentures.

    PubMed

    Shoi, K; Fueki, K; Usui, N; Taira, M; Wakabayashi, N

    2014-07-01

    It is well known that shortened dental arch decreases masticatory function. However, its potential to change brain activity during mastication is unknown. The present study investigates the effect of a shortened posterior dental arch with mandibular removable partial dentures (RPDs) on brain activity during gum chewing. Eleven subjects with missing mandibular molars (mean age, 66.1 years) on both sides received experimental RPDs with interchangeable artificial molars in a crossover trial design. Brain activity during gum chewing with RPDs containing (full dental arch) and lacking artificial molars (shortened dental arch) was measured using functional magnetic resonance imaging. Additionally, masticatory function was evaluated for each dental arch type. Food comminuting and mixing ability and the perceived chewing ability were significantly lower in subjects with a shortened dental arch than those with a full dental arch (P < 0.05). Brain activation during gum chewing with the full dental arch occurred in the middle frontal gyrus, primary sensorimotor cortex extending to the pre-central gyrus, supplementary motor area, putamen, insula and cerebellum. However, middle frontal gyrus activation was not observed during gum chewing with the shortened dental arch. These results suggest that shortened dental arch affects human brain activity in the middle frontal gyrus during gum chewing, and the decreased middle frontal gyrus activation may be associated with decreased masticatory function. © 2014 John Wiley & Sons Ltd.

  13. Dental arch dimensions in the mixed dentition: a study of Italian children born in the 1950s and the 1990s.

    PubMed

    Defraia, Efisio; Baroni, Giulia; Marinelli, Andrea

    2006-05-01

    The objective of this study was to compare the dental arch dimensions in the mixed dentition in two modern samples living in the same geographic area and separated by almost 35 years. A group of 83 subjects (39 boys and 44 girls) born between 1953 and 1959 (mean age: eight years and three months +/-15 months for the boys and seven years and 11 months +/-12 months for the girls) were compared with a group of 84 subjects (38 boys and 46 girls) born between 1990 and 1998 (mean age: eight years and eight months +/-12 months for the boys and eight years and four months +/-11 months for the girls). Measurements were taken on dental casts for posterior and anterior arch segments, intermolar and intercanine width, and mesiodistal size of incisors. The available anterior space in both arches and the posterior and anterior transverse dimensions were calculated. Groups were compared using a nonparametric test (Mann-Whitney U-test) for independent samples (P < .05). Results show that both boys and girls of 1990s showed significantly smaller maxillary intermolar width when compared with 1950s. Posterior transverse interarch discrepancy was significantly minor in girls of 1990s. The present population has a greater probability of developing a malocclusion as a consequence of the secular trend toward the reduction of the width of the upper arch.

  14. Evaluation of dental arch width and form changes after orthodontic treatment and retention with a new computerized method.

    PubMed

    Taner, Tülin Ugur; Ciger, Semra; El, Hakan; Germeç, Derya; Es, Alphan

    2004-10-01

    The purpose of this study was to evaluate longitudinal arch width and form changes and to define arch form types with a new computerized method. Maxillary and mandibular models of 21 Class II Division 1 patients were examined before treatment (T(0)), after treatment (T(1)), and an average of 3 years after retention (T(2)). Arch width measurements were made directly on scanned images of maxillary and mandibular models. Arch form changes at T(0)-T(1) and T(1)-T(2) were evaluated by superimposing the computer-generated Bezier arch curves with a computer program. Types of dental arch forms were defined by superimposing them with the pentamorphic arch system, which included 5 different types of arch forms: normal, ovoid, tapered, narrow ovoid, and narrow tapered. Maxillary arch widths were increased during orthodontic treatment. Mandibular posterior arch widths were also increased. The expansion of the mandibular arch forms was less than in the maxillary arch forms. Arch width changes were generally stable, except for reduction in maxillary and mandibular interlateral, inter-first premolar, and mandibular intercanine widths. Pretreatment maxillary arch forms were mostly tapered; mandibular arch forms were tapered and narrow tapered. In maxillary arch forms, 76% of the treatment changes were maintained. Mandibular arch form was maintained in 67% of the sample, both during treatment and after retention. In mandibular arches, 71% of orthodontically induced arch form changes were maintained.

  15. Factors Responsible for Unfavorable Dental Arch Relationship in non Syndromic Unilateral Cleft Lip and Palate Children.

    PubMed

    Haque, Sanjida; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli

    Multiple factors are whispered to be crucial cause of unfavourable dental arch relationship in cleft lip and palate (CLP).This study aims to evaluate the dental arch relationship of Bangladeshi children with non syndromic unilateral cleft lip and palate (UCLP) following cheiloplasty and palatoplasty. Also to explore the various congenital (UCLP type, UCLP side, family history of cleft, family history of class III) and environmental (cheiloplasty, palatoplasty) factors that affects dental arch relationship of UCLP patients. This was a retrospective study where 84 dental models were taken before orthodontic treatment and alveolar bone grafting. The mean age was 7.69± 2.46 (mean± SD). The dental arch relationship was assessed by GOSLON (Great Ormond Street, London and Oslo) Yardstick. According to GOSLON Yardstick, five categories are rated; named- 1: excellent; 2: good; 3: fair; 4: poor; 5: very poor. Also the groups have been dichotomized into favorable (category ratings 1-3) and unfavorable (category ratings 4 and 5) groups. Kappa statistics was used to evaluate the intra- and inter-examiner agreements and logistic regression analysis was used to explore the responsible factors that affect dental arch relationship. Total 37 subjects (44% of all subjects) were categorized into unfavourable group (category rating 4 and 5) using GOSLON yardstick. Intra- and inter-examiner agreements were very good. The mean GOSLON score was 3.238. Using crude and stepwise backward regression analysis, significant association was found between family history of skeletal class III malocclusion (p = 0.015 and p = 0.014 respectively) and unfavourable dental arch relationship. Complete UCLP (p = 0.054) and left sided UCLP (p = 0.053) also seemed to be correlated but not significant with unfavourable dental arch relationship using crude and stepwise backward regression analysis respectively. This analysis suggested that family history of skeletal class III was significantly correlated

  16. Correlation between maxillary central incisor crown morphology and mandibular dental arch form in normal occlusion subjects.

    PubMed

    Paranhos, Luiz Renato; Lima, Carolina Souto; da Silva, Ricardo Henrique Alves; Daruge Júnior, Eduardo; Torres, Fernando Cesar

    2012-01-01

    The aim of this study was to evaluate the correlation between the morphology of the mandibular dental arch and the maxillary central incisor crown. Cast models from 51 Caucasian individuals, older than 15 years, with optimal occlusion, no previous orthodontic treatment, featuring 4 of the 6 keys to normal occlusion by Andrews (the first being mandatory) were observed. The models were digitalized using a 3D scanner, and images of the maxillary central incisor and mandibular dental arch were obtained. These were printed and placed in an album below pre-set models of arches and dental crowns, and distributed to 12 dental surgeons, who were asked to choose which shape was most in accordance with the models and crown presented. The Kappa test was performed to evaluate the concordance among evaluators while the chi-square test was used to verify the association between the dental arch and central incisor morphology, at a 5% significance level. The Kappa test showed moderate agreement among evaluators for both variables of this study, and the chi-square test showed no significant association between tooth shape and mandibular dental arch morphology. It may be concluded that the use of arch morphology as a diagnostic method to determine the shape of the maxillary central incisor is not appropriate. Further research is necessary to assess tooth shape using a stricter scientific basis.

  17. Longitudinal evaluation of dental arch asymmetry in Class II subdivision malocclusion with 3-dimensional digital models.

    PubMed

    Veli, Ilknur; Yuksel, Burcin; Uysal, Tancan

    2014-06-01

    Class II subdivision malocclusions with their asymmetric occlusal relationships often pose treatment difficulties. The aim of this study was to evaluate the longitudinal changes of dental arch asymmetry in untreated subjects with Class II subdivision malocclusion. From 706 files from the University of Michigan Growth Study, longitudinal records of 17 untreated subjects with Class II subdivision malocclusion were included this study. Dental arch changes at 3 consecutive longitudinal intervals, defined by the cervical vertebral maturation method, were analyzed on digital dental models. The average ages of the subjects were 12.4, 15.1, and 19.1 years at the 3 time periods, respectively. Maxillary and mandibular reference lines were constructed and used for the intra-arch asymmetry measurements. The Friedman test and analysis of variance with repeated measures were used to determine dental arch asymmetries at the P <0.05 level. All subjects were found to have a type 1 Class II subdivision malocclusion characterized by distal positioning of the mandibular first molar on the Class II side. No statistically significant intra-arch asymmetry changes were found for the maxillary and mandibular dental arches in any time period. Between the baseline and the final follow-up, the data indicated decreases in maxillary and mandibular intercanine arch widths and arch lengths symmetrically. The results of this study indicate that the dental arch asymmetry in patients with Class II subdivision malocclusions did not improve or worsen with growth. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  18. Dental arch relationships on three-dimensional digital study models and conventional plaster study models for patients with unilateral cleft lip and palate.

    PubMed

    Asquith, J A; McIntyre, G T

    2012-09-01

    To determine if three-dimensional (3D) digital study models could replace plaster study models for the evaluation of dental arch relationships for patients with unilateral cleft lip and palate. Observational study involving plaster study models from a records archive. U.K. National Health Service. Thirty sets of study models of 5-year-old patients with unilateral cleft lip and palate were identified and scanned to produce 3D digital study models by ESM Digital Solutions Ltd. (Swords, Co. Dublin, Ireland) using an R250 Orthodontic Study Model Scanner (3Shape A/S, Copenhagen, Denmark). None. The plaster and 3D digital study models were scored using the 5-year-olds' and modified Huddart Bodenham indices and analyzed using the Friedman test (p < .05) and two-way ANOVA, respectively. Intra-observer and interobserver reproducibility were calculated from the 5-year-olds' index data using the weighted kappa statistic for both the plaster and 3D digital models. Intra-observer and interobserver reproducibility were good (0.62 to 0.83 and 0.64 to 0.78, respectively). There were no statistically significant differences between the scores for the 3D digital study models when compared to the plaster study models for either the 5-year-olds' index (p  =  .12) or for the modified Huddart Bodenham index (p  =  .506). Three-dimensional digital models are a valid alternative to traditional plaster study models for the evaluation of dental arch relationships in patients with unilateral cleft lip and palate.

  19. Evaluation of the fit of preformed nickel titanium arch wires on normal occlusion dental arches

    PubMed Central

    Al-Barakati, Rakhn G.; Alqahtani, Nasser D.; AlMadi, Abdulaziz; Albarakati, Sahar F.; ALKofide, Eman A.

    2015-01-01

    Aim To determine the fits of preformed nickel titanium (NiTi) archwires on dental arches with normal occlusion. Methods Forty sets of upper and lower plaster models were obtained from men and women with Class I occlusions. Preformed 0.016″ × 0.022″ NiTi archwires from Rocky Mountain Orthodontics (RMO), 3 M Unitek, Ormco, and Dentaurum were evaluated in terms of their fits on dental arches from male, female, and combined cases. Data were analyzed by using fourth- and sixth-order polynomial equations, analysis of variance (ANOVA), and the Duncan post hoc test. Results In the upper arches, the best fit and least error were obtained with RMO Ovoid and Ormco Orthos Large archwires for male cases, but with 3 M Orthoform LA archwires for female and combined cases. In the lower arches, the best fit and least error were obtained with Ormco Orthos Large for male cases, with 3 M Orthoform LA and RMO Normal for female cases, and with 3 M Orthoform LA, RMO Normal, Ormco Orthos Large, and Ormco Orthos Small for combined cases. When both dental arches were matched, Ormco Orthos Large was the best wire for male cases. 3 M Orthoform LA was the best wire for female and combined cases. Conclusions Using an archwire form with the best fit to the dental arch should produce minimal changes in the dental arch form when NiTi wires are used and require less customization when stainless-steel wires are used. PMID:26792965

  20. A computer program for the analysis of dental arch form using the catenary curve.

    PubMed

    BeGole, E A

    1981-01-01

    This paper presents the logic and details of a FORTRAN computer program which fits a two parameter catenary curve, using the method of least squares, to a set of data points arising from an exact size photograph of a dental model. Error is assessed by evaluating the difference between the observed and fitted y values. Finally, the length of the arc is measured. The program is useful in studies related to dental arch form as a part of orthodontic treatment. The measurement of the arc length provides as assessment of space available in the dental arch, which is an important part of treatment planning for the orthodontic patient.

  1. The randomized shortened dental arch study: influence of two different treatments on interdental spacing over 5 years.

    PubMed

    Kern, Jaana-Sophia; Wolfart, Stefan; Hilgers, Ralf-Dieter; Marré, Birgit; Scheller, Herbert; Strub, Jörg; Böning, Klaus; Hannak, Wolfgang; Luthardt, Ralph G; Heydecke, Guido; Huppertz, Jan; Pospiech, Peter; Wöstmann, Bernd; Stark, Helmut; Mundt, Torsten; Jahn, Florentine; Kern, Matthias; Edelhoff, Daniel; Walter, Michael H

    2017-07-01

    Being a secondary outcome in a multicenter randomized controlled trial, the present analysis focused on interdental spacing in the shortened dental arch (SDA). The aim was to evaluate changes in interdental spacing in dependence of two different treatments after an observation period of up to 5 years. Patients were either treated with a partial removable dental prosthesis (PRDP) for molar replacement (PRDP group) or according to the SDA concept aiming at a premolar occlusion (SDA group) in a randomized manner. Interdental spacing in the anterior region was measured with gauges and categorized as "0" (<0.1 mm), "1" (<0.5 mm), "2" (0.5-1 mm), and "3" (>1 mm). The statistical analysis was performed with analysis of variance models followed by linear contrast. Ninety-one patients (SDA n = 41, PRDP n = 50) were included. Changes of interdental spacing were detected in 70.7 % of all cases. A significant difference between the mean score changes was found in the mandible comparing the PRDP group and the SDA group. The respective mean score changes from baseline to 5 years were 0.23 (SD 0.49) for the PRDP group and 0.02 (SD 0.30) for the SDA group (p = 0.023). Major interdental spacing could be observed in neither of the groups. The SDA concept resulted in a slightly better outcome. When deciding whether to replace missing molars, the present results give further support to the SDA concept.

  2. Predictors of poor dental arch relationship in young children with unilateral cleft lip and palate.

    PubMed

    Hsieh, Yuh-Jia; Liao, Yu-Fang; Shetty, Akshai

    2012-08-01

    The aim of this cross-sectional outcome study using retrospective data capture of treatment histories was to examine the characteristics of young children with unilateral cleft lip and palate who had poor dental arch relationship (i.e., Goslon 5). The study sample comprised 120 children born with nonsyndromic complete unilateral cleft lip and palate between 1995 and 2003, and were aged between 5.0 and 7.0 years (mean age, 5.1 years) at the time of data collection. The dental arch relationship was assessed using the Goslon yardstick from intraoral dental photographs. An independent investigator recorded treatment histories from the clinical notes. The inter- and intraexaminer agreements evaluated by weighted kappa statistics were high. There was no association between dental arch relationship and the type of presurgical orthopedics or pharyngeal flap. Dental arch relationship was associated with the initial cleft size (odds ratio, OR = 1.3; 95% confidence interval, CI = 1.1-1.5, p < 0.01), surgeon grade for palate repair (OR = 5.0, 95% CI = 1.2-19.9, p < 0.05), and primary gingivoperiosteoplasty (OR = 2.8, 95% CI = 1.0-8.1, p = 0.05). These data suggest that intraoral dental photographs provide a reliable method for rating dental arch relationship. Wide initial cleft, high-volume surgeon, and primary gingivoperiosteoplasty are predictors of poor dental arch relationship outcome in young children with unilateral cleft lip and palate. These findings may improve treatment outcome by modifying the treatment protocol for patients with unilateral cleft lip and palate.

  3. Effects of unilateral premolar extraction treatment on the dental arch forms of Class II subdivision malocclusions.

    PubMed

    Dahiya, Ginu; Masoud, Ahmed I; Viana, Grace; Obrez, Ales; Kusnoto, Budi; Evans, Carla A

    2017-08-01

    A retrospective study evaluating posttreatment symmetry in dental arch form and midlines was carried out in Class II subdivision patients treated with unilateral and bilateral maxillary premolar extractions. Using Geomagic (version 14; Geomagic, Research Triangle Park, NC) and MATLAB (version 8.4; MathWorks, Natick, Mass) software, best-fit curves expressed as quartic polynomials were generated for 13 Class II subdivisions treated with unilateral extractions and 20 treated with bilateral maxillary premolar extractions. Transverse and sagittal measurements were recorded to assess symmetry. Dental models were superimposed on constructed reference planes to generate average posttreatment arches. Statistical comparisons were performed with the significance level set at P ≤0.05. The unilateral extraction group showed significant differences in transverse arch forms between the right and left sides in the anterior, anterior-middle, and middle segments of the arch, and all regions other than the posterior segment in the sagittal dimension. Significant differences were found between groups in the anterior and anterior-middle segments of the arch transversely, the middle and middle-posterior segments sagittally, and the midline deviation relative to the midsagittal plane. Superimposed average arches showed similar results. Unilateral maxillary extraction treatment generally results in a narrower and more posteriorly displaced arch form on the extraction side, with a deviated maxillary midline toward the extraction side of the arch. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  4. Correlation between dental arch width and sagittal dento-skeletal morphology in untreated adults.

    PubMed

    Shahroudi, Atefe Saffar; Etezadi, Tahura

    2013-11-01

    Dental arch form is one of the most important characteristics of dentition. However, this dimension usually receives less attention in diagnosis or treatment planning and orthodontic patients are traditionally classified with regard to their sagittal characteristics. The objectives of this study were to investigate if a relationship exists between the dental arch width (transverse dimension) and sagittal skeletal and dental parameters in orthodontic patients. Dental casts and lateral cephalograms of 108 consecutive untreated Iranian patients (47 males and 61 females) between 16 and 31 years of age were evaluated. Arch width (AW) parameters including upper and lower inter-molar width (UIMW and LIMW) and upper and lower inter-canine width (UICW and LICW) were measured by a digital caliper. Sagittal parameters included SNA and SNB angle and Wits' appraisal obtained from lateral cephalograms in addition to upper and lower arch length (UAL and LAL) obtained from dental casts. The correlation between the aforementioned parameters was evaluated applying Pearson correlation coefficients. Molar and canine relationship according to Angle's classification was also recorded and the means of all parameters were compared between three occlusal relationship classes and two gender groups by means of two-way ANOVA. According to statistical analysis a significant positive correlation between sagittal parameters and arch width measures exists between SNA and UICW and between LICW and LAL. Upper and lower ICW were significantly correlated, the relationship between upper and lower IMW and between UAL and LAL were significant. Among sagittal measures, both UAL and LAL were correlated with the ANB angle. The means of arch width parameters in three occlusal classes were not significantly different. The only significant correlation between arch width and sagittal parameters existed between UICW and SNA angle and between LICW and LAL. No significant difference of the arch width parameter

  5. Individual tooth macrowear pattern guides the reconstruction of Sts 52 (Australopithecus africanus) dental arches.

    PubMed

    Benazzi, Stefano; Kullmer, Ottmar; Schulz, Dieter; Gruppioni, Giorgio; Weber, Gerhard W

    2013-02-01

    The functional restoration of the occlusal relationship between maxillary and mandibular tooth rows is a major challenge in modern dentistry and maxillofacial surgery. Similar technical challenges are present in paleoanthropology when considering fragmented and deformed mandibular and maxillary fossils. Sts 52, an Australopithecus africanus specimen from Sterkfontein Member 4, represents a typical case where the original shape of the dental arches is no longer preserved. It includes a partial lower face (Sts 52a) and a fragmented mandible (Sts 52b), both incomplete and damaged to such an extent to thwart attempts at matching upper and lower dentitions. We show how the preserved macro wear pattern of the tooth crowns can be used to functionally reconstruct Sts 52's dental arches. High-resolution dental stone casts of Sts 52 maxillary and mandibular dentition were mounted and repositioned in a dental articulator. The occlusal relationship between antagonists was restored based on the analysis of the occlusal wear pattern of each preserved tooth, considering all dental contact movements represented in the occlusal compass. The reconstructed dental arches were three-dimensional surface scanned and their occlusal kinematics tested in a simulation. The outcome of this contribution is the first functional restoration of A. africanus dental arches providing new morphometric data for specimen Sts 52. It is noteworthy that the method described in this case study might be applied to several other fossil specimens.

  6. Dental arch diameters and relationships to oral habits.

    PubMed

    Aznar, T; Galán, A F; Marín, I; Domínguez, A

    2006-05-01

    The objective was to analyze variations in dental arch width in relation to oral habits. Maxillary and mandibular intercanine and intermolar distance were determined in relation to certain oral habits in 1297 children (ages 3 to 6 years). After an oral examination, the parents of each child completed a questionnaire about oral habits, including the use of a dummy or a bottle (or both), finger sucking, mouth breathing, breast- or bottle-feeding, and duration of these habits. Data were subjected to statistical analysis by the chi-square test for qualitative variables and analysis of variance for quantitative variables with homogeneous variances. Statistical significance was P < .05. In general, the maxillary arch was larger than the mandibular arch with regard to both the intercanine and the intermolar distances and more significantly so in boys. In relation to age, a significant increase was found only for the mandibular intercanine distance (P = .001). When arch width was analyzed in relation to various oral habits, the maxillary intercanine distance was less in children who used a dummy, especially one of a round design (P = .003). The maxillary intercanine distance was also less in children who breathed through their mouth (P = .002). In most cases, dummy use and mouth breathing were associated with a reduction in the intercanine distance in the maxillary arch. A dummy habit leads to a reduction in maxillary arch width, and mouth breathing causes a reduction in the size of both arches.

  7. Dental arch asymmetry in young healthy human subjects evaluated by Euclidean distance matrix analysis.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Serrao, G

    1993-03-01

    Form differences between biological structures can be evaluated using several approaches. A recently proposed method (Euclidean distance matrix analysis; EDMA) seems to be able to differentiate between size and shape differences. Here it has been applied to study the asymmetry of mandibular and maxillary arches in 50 men and 45 women with sound dentitions. The centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar) were individualized on the dental casts of subjects. The form of the right and left maxillary and mandibular hemi-arches was separately assessed by calculating all the possible linear distances between pairs of teeth within arch and side. Side differences were tested by EDMA. In men, the maxillary and the mandibular arches were both symmetrical (i.e. there were no significant differences in size or shape between the left and right hemi-arches). In women, the mandibular arch was symmetrical, but in the maxillary arch the two antimeres had a significantly different shape. No size differences were found between the left and right female hemi-arches.

  8. Double arch mirror study

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    The development of a method of mounting light weight glass mirrors for astronomical telescopes compatible with the goals of the Shuttle Infrared Telescope Facility (SIRTF) was investigated. A 20 in. diameter double arch lightweight mirror previously fabricated was modified to use a new mount configuration. This mount concept was developed and fabricated. The mounting concept of the double mounting mirror is outlined. The modifications made to the mirror, fabrication of the mirror mount, and room temperature testing of the mirror and mount and the extension of the mirror and mount concept to a full size (40 in. diameter) primary mirror for SIRTF are discussed.

  9. Effects of early treatment on maxillary arch development in BCLP. A study on dental casts between 0 and 4 years of age.

    PubMed

    Heidbuchel, K L; Kuijpers-Jagtman, A M; Van't Hof, M A; Kramer, G J; Prahl-Andersen, B

    1998-06-01

    The present investigation analyses longitudinally the effects of early orthopaedic and/or surgical treatment on maxillary alveolar arch development in 30 children with a complete bilateral cleft lip and palate (BCLP). Palatal arch dimensions were measured on dental casts and their growth velocities during different treatment periods were calculated. Differences in growth velocities between consecutive treatment periods were examined and tested statistically. Furthermore, growth velocities were compared with those of 80 non-cleft children. Before lip closure, growth of the intercanine width of children with a BCLP and non-cleft children was comparable. Only for arch length significantly was less growth observed in BCLP patients in comparison with the control group. After lip closure, intercanine width, arch length and segmental angle diminished. During the intersurgical period, arch form seemed to adapt to a new muscular balance. Immediately after soft palate surgery, growth of the intercanine width and intertuberosity width was restricted. This negative growth was compensated in the postsurgical period, where a catch-up growth of intertuberosity width was even observed.

  10. [Dental alveolar bone and dental arch remodeling in children: orthodontic diagnosis and treatments based on individual child arch development].

    PubMed

    Xiaobing, Li

    2016-12-01

    The etiology of malocclusions basically involves both congenital and environmental factors. Malocclusion is the result of the abnormal development of the orofacial complex (including tooth, dental alveolar bone, upper and lower jaws). Early orthodontic interceptive treatments involve the elimination of all congenital and environmental factors that contribute to the malformation of the orofacial complex, as well as interrupt the deviated development of the orofacial complex and the occlusion. Early orthodontic interceptive treatments mainly aim to use children's growth potential to correct abnormal developments of occlusions and orthodontically treat malocclusions more efficiently. The early orthodontic interceptive treatments include correcting the child's bad oral habits, training the abnormal functioned para-oral muscles, maintaining the normal eruptions of succeeding permanent teeth, applying interceptive treatments to the mal-developed teeth, and employing functional orthopedic treatments for abnormal growths of the upper and lower jaws. In orthodontics, correcting mal-positioned teeth is called orthodontic treatment, while rectifying the abnormal relationships of the upper and lower jaws is called functional orthopedic treatment. However, no clear definition is available as regards to the early orthodontic interceptive treatment of malocclusions caused by the deviated development of the dental alveolar bone. This new theory of "early dental alveolar bone and dental arch remodeling technique" was proposed by Professor Li Xiaobing of the Department of Pediatric Dentistry, Faculty of Pediatric Dentistry and Orthodontics in West China Hospital of Stomatology through his clinical analyses and investigation of his early orthodontic interceptive treatments. He defined the early orthodontic corrections of abnormal growth of dental alveolar bone as "remodel". The "early dental alveolar bone and dental arch remodeling theory and technique" is proved useful in

  11. Complete-arch implant-supported monolithic zirconia fixed dental prostheses: A systematic review.

    PubMed

    Abdulmajeed, Aous A; Lim, Kevin G; Närhi, Timo O; Cooper, Lyndon F

    2016-06-01

    Monolithic zirconia prostheses are emerging as a promising option in the implant-based rehabilitations of edentulous patients, yet their clinical performance is not fully documented. The purpose of this systematic review was to assess the clinical performance of complete-arch implant-supported monolithic zirconia fixed dental prostheses. The electronic databases PubMed, Science Direct, and Cochrane Library were searched for clinical studies on complete-arch implant-supported monolithic zirconia fixed dental prostheses. Human studies with a mean follow-up of at least 1 year and published in an English-language peer-reviewed journal up to June 2015 were included. Two independent examiners conducted the search and the review process. The search generated 903 titles. Eighteen qualifying studies were retrieved for full-text evaluation. Nine studies were included on the basis of preestablished criteria. Eight studies reported satisfactory clinical and esthetic outcomes. One study demonstrated prosthesis failure. Clinical studies are lacking on the long-term outcome of complete-arch implant-supported monolithic zirconia prostheses. Complete-arch dental implant restoration with monolithic zirconia is associated with high short-term success. Despite the many advantages and short-term favorable reports, studies of longer duration are necessary to validate the broad application of this therapy. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  12. Comparison of dental and apical base arch forms in Class II Division 1 and Class I malocclusions.

    PubMed

    Ball, Randy L; Miner, R Matthew; Will, Leslie A; Arai, Kazuhito

    2010-07-01

    The purpose of this study was to compare the mandibular dental arch form and the mandibular basal bone arch form of patients with Class I malocclusion with those of patients with Class II Division 1 malocclusion. Our aims were to determine differences in dental and basal transverse dimensions and arch forms between the 2 groups, and to determine the usefulness of WALA points as a reference for predicting a stable dental arch form in Class II Division 1 patients. Three-dimensional graphic representations of mandibular casts from 35 Class I malocclusion patients and 32 Class II Division 1 patients were created by using a laser scanning system. Anatomic reference points were subjectively identified and used to represent the dental arch form (FA points) and the arch form of the basal bone (WALA points). The FA point intercanine width was found to be significantly larger in the Class II Division 1 sample compared with the Class I sample, whereas the basal arch form, represented by the WALA ridge, was not significantly different. No significant difference was found in the FA points for intermolar width or in the arch form of the basal bone between the 2 groups. A highly significant correlation between basal and dental arch forms was found at the canine and molar areas in the Class II Division 1 sample, and the FA and WALA point arch forms were highly individual in the Class II Division 1 sample. The mandibular dental arch forms for both the Class I and Class II samples were essentially the same, except at the canines; this is likely due to the nature of the occlusion in Class II Division 1 patients. There was no difference in arch forms of the basal bone between the 2 groups. The use of WALA points or other anatomic landmarks of the basal bone to predict the ideal dental arch form for a patient seems possible and could ensure a more stable orthodontic treatment outcome. Copyright (c) 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  13. Dental arch dimensional changes after adenoidectomy or tonsillectomy in children with airway obstruction

    PubMed Central

    Zhu, Yanfei; Li, Jiaying; Tang, Yanmei; Wang, Xiaoling; Xue, Xiaochen; Sun, Huijun; Nie, Ping; Qu, Xinhua; Zhu, Min

    2016-01-01

    Abstract Background: Children with severe airway obstruction tend to have a vertical direction of growth, class II malocclusion, and narrow arches. Adenoidectomy and tonsillectomy were recommended for the promotion of balanced dentition growth in these children. The aim of this study was to determine the effect of adenoidectomy and tonsillectomy on the growth of dental morphology in children with airway obstruction. Methods: A comprehensive search of the Medline, Embase, Web of science, and OVID databases for studies published through to January 17, 2016 was conducted. Prospective, comparative, clinical studies assessing the efficacy of adenoidectomy, or tonsillectomy in children with airway obstruction were included. The weighted mean difference (WMD) and 95% confidence interval (CI) were used for continuous variables. Forest plots were drawn to demonstrate effects in the meta-analyses. Results: Eight papers were included in our study. We found that adenoidectomy and tonsillectomy led to a significant change in nasal-breathing in children with airway obstruction. Children with airway obstruction had a significantly narrower posterior maxillary dental arch than children without airway obstruction (WMD = −0.94, 95% CI [−1.13, −0.76]; P < 0.001). After surgery, these children still had a significantly narrower dental arch than the nasal-breathing children (WMD = −0.60, 95% CI [−0.79, −0.42]; P < 0.001). In terms of dental arch width, malocclusion, palatal height, overjet, overbite, dental arch perimeter, and arch length, a tendency toward normalization was evident following adenoidectomy or tonsillectomy, with no significant differences evident between the surgical group and the normal group. The small number of studies and lack of randomized controlled trials were the main limitations of this meta-analysis. Conclusions: Following adenoidectomy and tonsillectomy, the malocclusion and narrow arch width of children with airway obstruction could not

  14. Shape variation and covariation of upper and lower dental arches of an orthodontic population

    PubMed Central

    Halazonetis, Demetrios J.

    2016-01-01

    Summary Objectives: This study aimed to quantify the patterns of shape variability and the extent and patterns of shape covariation between the upper and lower dental arch in an orthodontic population. Methods: Dental casts of 133 white subjects (61 males, 72 females; ages 10.6–26.6) were scanned and digitized in three dimensions. Landmarks were placed on the incisal margins and on the cusps of canines, premolars, and molars. Geometric morphometric methods were applied (Procrustes superimposition and principal component analysis). Sexual dimorphism and allometry were evaluated with permutation tests and age–size and age–shape correlations were computed. Two-block partial least squares analysis was used to assess covariation of shape. Results: The first four principal components represented shape patterns that are often encountered and recognized in clinical practice, accounting for 6–31 per cent of total variance. No shape sexual dimorphism was found, nevertheless, there was statistically significant size difference between males and females. Allometry was statistically significant, but low (upper: R 2 = 0.0528, P < 0.000, lower: R 2 = 0.0587, P < 0.000). Age and shape were weakly correlated (upper: R 2 = 0.0370, P = 0.0001, lower: R 2 = 0.0587, P = 0.0046). Upper and lower arches covaried significantly (RV coefficient: 33 per cent). The main pattern of covariation between the dental arches was arch width (80 per cent of total covariance); the second component related the maxillary canine vertical position to the mandibular canine labiolingual position (11 per cent of total covariance). Limitations: Results may not be applicable to the general population. Age range was wide and age-related findings are limited by the cross-sectional design. Aetiology of malocclusion was also not considered. Conclusions: Covariation patterns showed that the dental arches were integrated in width and depth. Integration in the vertical dimension was weak, mainly restricted to

  15. Dental crowding in primary dentition and its relationship to arch and crown dimensions among preschool children of Davangere.

    PubMed

    Prabhakar, A R; Ravi, G R; Kurthukoti, Ameet J; Shubha, A B

    2008-01-01

    The purpose of the present study was to evaluate dental crowding in the deciduous dentition and its relationship to the crown and the arch dimensions among preschool children of Davangere. Stratified randomized selection of one hundred, 3-4 year old healthy children with all primary teeth erupted was done and divided into two groups. One group had children with anterior crowding in both the arches while the other had spacing. Alginate impressions of the upper and lower arches were made and the study casts were obtained. The tooth and arch dimensions were determined. Mesiodistal dimensions of all the teeth were significantly larger in the crowded arch group. However, the buccolingual dimensions of the maxillary right central incisor, mandibular lateral incisors and the maxillary molars and the crown shape ratio of maxillary lateral incisors, mandibular canines and mandibular right second molar was statistically different. No significant correlation was found between the arch width and the presence of crowding of deciduous dentition. The arch depth of the spaced dentition was greater when compared to the crowded ones. The arch perimeter of the crowded arches was significantly less than the spaced arches.

  16. Association of breastfeeding and three-dimensional dental arch relationships in primary dentition.

    PubMed

    Sum, Fung Hou Kumoi Mineaki Howard; Zhang, Linkun; Ling, Hiu Tung Bonnie; Yeung, Cindy Po Wan; Li, Kar Yan; Wong, Hai Ming; Yang, Yanqi

    2015-03-10

    The benefits of breastfeeding on oral health are still inconclusive, especially the association on occlusion. This study aimed to investigate the association of breastfeeding and the development of primary dentition. A cross-sectional study was conducted with 851 Asian children aged 2-5 years old in Hong Kong. Questionnaires were completed by the parents to collect information on breastfeeding and the non-nutritive sucking habits. The children's dental arch relationships were examined in the sagittal, vertical, and transverse dimensions by an experienced examiner. Children who experienced pure breastfeeding for more than 6 months had a lower chance of developing a class II incisal relationship (P < 0.05) or an increased overjet (P < 0.05), and had wider intercanine (P < 0.05) and intermolar widths (P < 0.05). Vertically, no association on the extent of overbite or openbite was found (P > 0.05). Pure breastfeeding for more than 6 months is positively associated with primary dental arch development in the anterior sagittal dental segment and on the horizontal arch width in primary dentition. Therefore, pure breastfeeding for more than 6 months is recommended, as it is associated with lower chance of the development of abnormal dental relationships. The results will be valuable for education and promotion of maternal breastfeeding.

  17. Comparison between dental and basal arch forms in normal occlusion and Class III malocclusions utilizing cone-beam computed tomography

    PubMed Central

    Suk, Kyung Eun; Park, Jae Hyun; Bayome, Mohamed; Nam, Young-Ok; Sameshima, Glenn T.

    2013-01-01

    Objective The purpose of this study was to investigate the relationship between the mandibular dental and basal arch forms in subjects with normal occlusion and compare them with those of Class III malocclusion using cone-beam computed tomography (CBCT). Methods CBCT images of 32 normal occlusion (19 males, 13 females; 24.3 years) and 33 Class III malocclusion subjects (20 males, 13 females, 22.2 years) were selected. Facial axis and root center points were identified from the left to right mandibular first molars. Distances between the facial axis and root center points for each tooth were calculated, and 4 linear and 2 ratio variables were measured and calculated for each arch form. The variables were compared between groups by independent t-test. Pearson correlation coefficient was applied to assess the relationships between dental and basal variables within each group. Results The mandibular dental and basal intercanine widths were significantly greater in the Class III group than in normal occlusion subjects (p < 0.05). The dental and basal intercanine widths as well as the dental and basal intermolar widths were strongly correlated in normal occlusion and moderately correlated in Class III malocclusion. Conclusions The dental arch form demon strated a strong positive correlation with the basal arch form in the normal occlusion group and moderate correlation in the Class III malocclusion group. These results might be helpful for clinicians to have a better understanding of the importance of basal arch form in the alveolar bone. PMID:23504406

  18. Anteroposterior dental arch and jaw-base relationships in a population sample.

    PubMed

    Zhou, Lei; Mok, Chung-Wai; Hägg, Urban; McGrath, Colman; Bendeus, Margareta; Wu, John

    2008-11-01

    To determine the association between the anteroposterior relationship of the dental arch and the anteroposterior relationship of the jaw-base in a Chinese population sample. Orthodontic casts and lateral cephalograms were obtained from a random sample of 405 twelve-year-old Chinese children from a population survey in Hong Kong. Angle's classification was used to assess the dental arch relationship from orthodontic casts. The jaw-base relationship was assessed from the lateral cephalograms using angular (ANB angle) and linear (Wits analysis) measurements. The correlation between the anteroposterior dental arch and jaw-base relationships was assessed. The anteroposterior dental arch did coincide with the jaw-base relationships, as expressed by the ANB angle in 61%, the Wits analysis in 67%, and with both in 53%. The jaw-base relationship assessed with the Wits analysis was more significantly associated with the dental arch relationship (P < .001) than that assessed with the ANB angle (P < .01). The correlation coefficient between the ANB angle and the Wits appraisal was .65 for the combined sample, and .60, .64, and .67 for Class I, II, and III dental arch relationships. In this population, the anteroposterior relationship of the dental arch and jaw-base fail to match in at least one out of every three individuals. Linear measurement of anteroposterior jaw-base relationships is a more valid reflection of the dental arch relationship than angular measurements.

  19. Duration of nutritive and nonnutritive sucking behaviors and their effects on the dental arches in the primary dentition.

    PubMed

    Warren, John J; Bishara, Samir E

    2002-04-01

    The purpose of this study was to determine the association between the duration of nutritive and nonnutritive sucking behaviors and various occlusal characteristics in the primary dentition. Sucking behavior data were collected on 372 children followed longitudinally from birth by using periodic questionnaires completed by parents. Study models were obtained from the children at 4 to 5 years of age and assessed for posterior crossbite, anterior open bite, and overjet. Dental arch parameters including arch widths, arch lengths, and arch depths were measured directly from the models. The subjects were grouped according to type of habit (pacifier or digit) and duration of nonnutritive sucking behaviors (less than 12, 12 to 24, 24 to 36, 36 to 48, and more than 48 months). Children with nonnutritive sucking of less than 12 months were further grouped according to the duration of breast-feeding. The dental arch and the occlusal characteristics were then compared among these groups. The results indicated no relationship between duration of breast-feeding during the first year of life and any dental arch or occlusal parameters. The study found that prolonged pacifier habits resulted in changes to the dental arches and the occlusal parameters that were different from the effects of digit sucking. In addition, some changes in the dental arch parameters and occlusal characteristics (eg, prevalence of posterior crossbite and increased amount of overjet) persisted well beyond the cessation of the pacifier or digit habit. Although further study is needed to determine the effects of nonnutritive sucking behavior in the mixed dentition, the results suggest that current recommendations for discontinuing these habits may not be optimal in preventing habit-related malocclusions.

  20. Transverse effect of Haas and Hyrax appliances on the upper dental arch in patients with unilateral complete cleft lip and palate: A comparative study

    PubMed Central

    Façanha, Anna Júlia de Oliveira; Lara, Tulio Silva; Garib, Daniela Gamba; da Silva Filho, Omar Gabriel

    2014-01-01

    Objective The aim of the present study was to evaluate the transverse effect of rapid maxillary expansion in patients with unilateral complete cleft lip and palate while comparing the Haas and Hyrax appliances. Methods The sample consisted of 48 patients divided into two groups: Group I - 25 patients treated with modified Haas appliance (mean age: 10 years 8 months); and Group II - 23 patients treated with Hyrax appliance (mean age: 10 years 6 months). Casts were taken during pre-expansion and after removal of the appliance at the end of the retention period. The models were scanned with the aid of the 3 Shape R700 3D scanner. Initial and final transverse distances were measured at cusp tips and cervical-palatal points of maxillary teeth by using the Ortho AnalyzerTM 3D software. Results The mean expansion obtained between cusp tips and cervical-palatal points for inter-canine width was 4.80 mm and 4.35 mm with the Haas appliance and 5.91 mm and 5.91 mm with the Hyrax appliance. As for first premolars or first deciduous molars, the values obtained were 6.46 mm and 5.90 mm in the Haas group and 7.11 mm and 6.65 mm in the Hyrax group. With regard to first molars, values were 6.11 mm and 5.24 mm in the Haas group and 7.55 mm and 6.31 mm in the Hyrax group. Conclusion Rapid maxillary expansion significantly increased the transverse dimensions of the upper dental arch in patients with cleft palate, with no significant differences between the Hass and Hyrax expanders. PMID:24945513

  1. Influence of the mode of nutritive and non-nutritive sucking on the dimensions of primary dental arches.

    PubMed

    Diouf, Joseph Samba; Ngom, Papa Ibrahima; Badiane, Alpha; Cisse, Binta; Ndoye, Cheikh; Diop-Ba, Khady; Diagne, Falou

    2010-12-01

    Sucking is innate in both infants and young children. It is termed nutritive when referring to suckling from the breast or bottle-feeding and non-nutritive when applied to sucking of a digit or pacifier. Few studies have attempted to assess the impact of the type of sucking on the size of the dental arches. The aim of this study was to quantify the influence of the mode of nutritive suckling and non-nutritive sucking habits (NNSH) on the measurements of the dental arches. This was a transverse descriptive study involving 226 Senegalese children. The mode of feeding and the presence or not of a NNSH (digit or pacifier) were gathered from parents of all children using a structured questionnaire. Quantitative variables regarding intra- and inter-arch relationships were recorded using plaster moulds taken from the children. Statistical analyses were used to compare the different variables according to gender, the mode of feeding and the presence or not of a NNSH. The subjects in the study (123 boys and 103 girls) were aged between 5 and 6years old. The children who had enjoyed mixed feeding (breast/bottle combination) had a great length of the anterior maxillary arch and a significantly greater depth of the palatal arch than children receiving breast-feeding alone. The children with antecedents or a current NNSH had a longer anterior maxillary arch than subjects with no NNSH (P=0.01). Regarding inter-arch relationships, the children with antecedents or a current digit-sucking habit had less overbite than their peers who had no NNSH (P=0.04). The results of this study show that bottle-feeding, even partial, as well as NNSH are associated with changes in certain dimensions of the maxillary dental arch and in inter-arch relationships. Longitudinal studies are required to investigate further the nature of this association. Copyright © 2010 CEO. Published by Elsevier Masson SAS. All rights reserved.

  2. Three-dimensional dental arch curvature in human adolescents and adults.

    PubMed

    Ferrario, V F; Sforza, C; Poggio, C E; Serrao, G; Colombo, A

    1999-04-01

    The three-dimensional arrangement of dental cusps and incisal edges in human dentitions has been reported to fit the surface of a sphere (the curve of Monson), with a radius of about 4 inches in adults. The objective of the current study was to compare the three-dimensional curvature of the mandibular dental arch in healthy permanent dentitions of young adults and adolescents. The mandibular casts of 50 adults (aged 19 to 22 years) and 20 adolescents (aged 12 to 14 years) with highly selected sound dentitions that were free from temporomandibular joint problems were obtained. The three coordinates of cusp tips excluding the third molars were digitized with a three-dimensional digitizer, and used to derive a spherical model of the curvature of the occlusal surfaces. From the best interpolating sphere, the radii of the left and right curves of Spee (quasi-sagittal plane) and of molar curve of Wilson (frontal plane) were computed. Mandibular arch size (interdental distances) was also calculated. The occlusal curvature of the mandibular arch was not significantly influenced by sex, although a significant effect of age was found (Student t, P <.005). The radii of the overall sphere, right and left curves of Spee, and curve of Wilson in the molar area were about 101 mm in adults, and about 80 mm in adolescents. Arch size was not influenced by either sex or age. The different curvatures of the occlusal plane in adolescents and adults may be explained by a progressive rotation of the major axis of the teeth moving the occlusal plane toward a more buccal position. These dental movements should be performed in a frontal plane on an anteroposterior axis located next to the dental crown.

  3. [Effect of dental arch length decrease during orthodontic treatment in the upper airway development. A review].

    PubMed

    Haddad, Stéphanie; Kerbrat, Jean-Baptiste; Schouman, Thomas; Goudot, Patrick

    2017-03-01

    A possible relation between an upper airway space decrease and the development of obstructive sleep apnea syndrom explains the importance to know the effect of the modification of dental arch length on the upper airway during orthodontic treatment. The aim of this article is to expose recent knowledge about upper airway development and dental arch length decrease factors, to determine the influence of this decrease on upper airway development. A review was done to determine the upper airway normal development, to define dental arch to specify if an ideal position of dental arch on apical base exists. All of the length dental arch decrease factors during orthodontic treatment (dental extraction, dental agenesis and dental malpositions) and their upper airway resounding were searched. Some authors found a diminution of upper airway space after premolars extractions while others didn't found this diminution after extractions premolars when incisor retraction is finished. A decrease of transversal maxillary diameter and nasal cavity may be due to absence of permanent teeth. The effect of dental arch length decrease during orthodontic treatment in the upper airway development was not scientifically proved. However we had to be vigilant and adapt our orthodontic treatment case by case to avoid an upper airway modification. © EDP Sciences, SFODF, 2017.

  4. Dental arch changes in postretention in Class II division 1 extraction cases.

    PubMed

    Anuwongnukroh, Niwat; Dechkunakorn, Surachai; Kunakornporamut, Kannida; Tua-Ngam, Peerapong

    2017-06-01

    The purpose of this study is to evaluate the postretention stability of the dental arches in Class II division 1 patients treated with four bicuspid extractions and the edgewise technique. A digital caliper was used to analyze the dental casts from 29 Class II division 1 malocclusion patients with skeletal type II (14 males, 15 females; ages ranging from 10.2-18.0 years), treated with four bicuspid extractions and the edgewise technique. Intercanine width, intermolar width, arch length, irregularity index, overjet and overbite were evaluated at three times: pretreatment (T1), posttreatment (T2) and postretention (T3) (mean: 4.15 years). Student's t-tests were used to compare the pretreatment-posttreatment, posttreatment-postretention and pretreatment-postretention. Significance was determined at P<0.05. The results of the study are listed as: (1) The upper and lower intercanine widths significantly increased (P<0.05) between T1-T2 and decreased between T2-T3. However, no significant changes were observed between T1-T3; (2) The upper and lower intermolar widths significantly decreased (P<0.05) between T1-T2, between T2-T3 and between T1-T3, except for the upper intermolar width between T2-T3 which showed no significant change; (3) The upper and lower arch lengths significantly decreased (P<0.05) at posttreatment and postretention due to the closure of extraction spaces. Both the upper and lower arch lengths significantly decreased between T1-T2, T2-T3, and T1-T3, except for the upper arch length between T2-T3, which showed no significant change; (4) The irregularity index was significantly improved after treatment. However, there was a slight increase in incisor irregularity at postretention. At postretention, 75.86% of the patients had mild crowding, 20.68% had moderate crowding, 3.48% had severe crowding; (5) The overjet and overbite significantly decreased (P<0.05) between T1-T2 and increased between T2-T3. The changes in the dental arches were small at

  5. Clinical performance of cantilevered fixed dental prostheses abutments in the shortened dental arch.

    PubMed

    Sasse, Martin; Kern, Matthias; Marré, Birgit; Walter, Michael H

    2014-03-01

    This article is part of a randomized clinical trial on different treatments in the shortened dental arch (SDA). It focused on the abutment tooth prognosis with cantilevered fixed dental prostheses (CFDPs). Sixty-two patients with a bilaterally SDA up to the first or second premolar in the mandible or maxilla were evaluated. In 57 of 124 quadrants, second premolars were replaced by a CFDP (cantilever group). In the remaining 67 quadrants, a natural second premolar was present and thus no need for a CFDP was given (non-cantilever group). Patients were recalled annually up to 5 years. The mean observation period was 56.3 months (min. 3.0, max. 76.2, SD 16.1). Kaplan-Meier survival rates concerning tooth loss and tooth fracture were 93.9%/94.0% in the cantilever group and 91.9%/92.8% in the non-cantilever group. Differences between both groups were not significant. The survival rate concerning loss of retention of CFDP retainers was 92.1% in the cantilever group. After 5 years of clinical service, CFDPs for the replacement of the second premolar showed no negative impact on the abutment tooth prognosis. Cantilevered fixed dental prostheses present a viable treatment option in the shortened dental arch without compromising the medium-term abutment tooth prognosis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Reliability of antagonistic arch impression in dental prostheses: clinical evaluation of different preimpression preparation procedures.

    PubMed

    Scotti, R; Lugli, M; D'Elia, A

    1995-08-01

    This study compared the influence of different methods of preimpression preparation on the quality of occlusal reproduction in irreversible hydrocolloid impressions. A total of 30 impressions of the lower dental arch of a patient were made with five different preimpression preparation procedures. Stone casts were made and analyzed. Critical comparison showed that the preimpression preparation influenced the quality of the occlusal surface of the cast. Fingerpainting the occlusal surface with fluid hydrocolloid before positioning the loaded impression tray, associated with use of a saliva ejector, reduced the incidence of macroscopic defects on the occlusal surface of the impressions.

  7. A 40 years follow-up of dental arch dimensions and incisor irregularity in adults.

    PubMed

    Tsiopas, Nikolaos; Nilner, Maria; Bondemark, Lars; Bjerklin, Krister

    2013-04-01

    Dentoalveolar changes in adulthood have not been extensively documented. Such changes may have important implications for the long-term stability of orthodontic treatment. To analyse occlusal and dentoalveolar changes in adults from the age of 20 years to the age of 60 years. The material comprised 18 Swedish dentists, 16 men and 2 women, with no missing teeth and no prosthodontic or orthodontic treatment. Measurements were recorded on study casts made between 1949 and 1989 at the Department of Stomatognathic Physiology at the Faculty of Odontology in Malmö, thus documenting changes over an average period of 38.4 years. Malocclusion traits, overbite, overjet, dental arch length and width, and Little's irregularity index were registered. There was a significant increase in Little's irregularity index in the mandible (1.0 mm, P < 0.01) and a decrease in arch length in both jaws (0.5-0.9 mm, P < 0.05). The maxillary and mandibular intercanine widths decreased by 0.8 and 1.0 mm, respectively (P < 0.001). The malocclusion traits, overbite, and overjet remained unchanged during the observation period. The results confirm that dentoalveolar changes occur as a continuous process throughout adult life. The findings of potential clinical importance are decreases in arch length and depth, resulting in a decrease in intercanine width and an increase in anterior crowding. In clinical orthodontic practice, these findings have important implications for treatment planning and long-term stability after orthodontic treatment.

  8. Three-dimensional digital evaluation of dental arches in infants with cleft lip and/or palate.

    PubMed

    Fernandes, Viviane Mendes; Jorge, Paula Karine; Carrara, Cleide Felício Carvalho; Gomide, Márcia Ribeiro; Machado, Maria Aparecida Andrade Moreira; Oliveira, Thais Marchini

    2015-01-01

    The aim of this study was to measure and compare the dimensions of the dental arches on three-dimensional digital study models in children with and without cleft lip and palate before the primary surgery. The sample consisted of 223 digital models of children aged 3-9 months, divided into 5 groups: without craniofacial deformities, unilateral and bilateral incomplete cleft lip and alveolus, unilateral and bilateral complete cleft lip and alveolus, unilateral cleft lip and palate, and bilateral cleft lip and palate. Dental casts of the maxillary dental arches of the children were used. The dental casts underwent a process of scanning through 3D scanner and the measurements used for the correlation among groups were made on the scanned images. Statistical analysis was performed by t test and ANOVA followed by Tukey test. The results showed that the intercanine distance and anterior cleft width was wider in children with unilateral cleft lip and palate. The intertuberosity distances and posterior cleft width was wider in children with bilateral cleft lip and palate among the groups. Children with cleft lip and palate before the primary surgery had wider maxillary arch dimensions than the children without cleft lip and palate.

  9. Impact of shortened dental arches on oral health-related quality of life.

    PubMed

    Antunes, J L F; Tan, H; Peres, K G; Peres, M A

    2016-03-01

    This study described the prevalence of adults with shortened dental arches (SDA) in Brazil, specifically assessing the differences of oral health-related quality of life [the prevalence and severity of oral impacts on daily performance (OIDP)] by dentition status. We analysed data from the 2010 National Survey of Oral Health in Brazil, including home interviews and oral examinations. The assessment of SDA used two alternative definitions: having 3-5 natural occlusal units (OUs) in posterior teeth or having 4 OUs in posterior teeth. Both definitions included having intact anterior region and no dental prosthesis. The analysis was weighted, and a complex sampling design was used. Negative binomial regression models assessed associations as adjusted for socio-demographic conditions and dental outcomes. A total of 9779 adults (35-44 years old) participated in the study. A non-negligible proportion had SDA: 9·9% and 3·8% for the first and second definition, respectively. Individuals with SDA (first definition) ranked higher in OIDP prevalence [count ratio (CR) 1·22; 1·09-1·36, 95% confidence interval (CI)] and severity (CR = 1·43; 1·19-1·72, 95% CI) than those with more natural teeth. This difference was not statistically significant when adjusted for socio-demographic and dental covariates: OIDP prevalence (CR = 1·04; 0·92-1·17, 95% CI) and severity (CR = 1·09; 0·91-1·30, 95% CI). Analogous results were obtained when the second definition of SDA was adopted. These findings suggest that a considerable contingent of adults may function well without dental prostheses, despite having several missing teeth. This conclusion challenges the traditional approach of replacing any missing tooth and instructs the allocation of more dental resources to preventive, diagnostic and restorative services.

  10. Spacing in deciduous dentition of Polish children in relation to tooth size and dental arch dimensions.

    PubMed

    Janiszewska-Olszowska, Joanna; Stepien, Piotr; Syrynska, Maria

    2009-05-01

    To assess the prevalence of primary and secondary spacing in the deciduous dentition and its correlation to tooth widths and dental arch dimensions. Dental casts of 50 preschool children free from malocclusion, were analysed. The width of each space was measured as the smallest distance between the proximal surfaces of the neighbouring teeth, parallel to the occlusal plane. Crown width was measured as the greatest distance between the mesial and distal surfaces of the crown, parallel to the occlusal plane. Intercanine widths were measured between cusp tips of upper and lower canines. Intermolar widths were measured between the central fossae of the second molars. Arch lengths were measured from the midpoint between the central incisors to the midpoint between the distal surfaces of the deciduous second molars. The primary spaces were present in the upper dental arch in 90% children, on the average 2.09 mm in maxilla and 1.25 mm in mandible. Their widths were dependent on upper intercanine width. Secondary spacing was present in 92% children in the upper dental arch (mean 2.86 mm) and 90% in the lower (mean 3.08 mm). Lower secondary spacing was correlated to lower intercanine width and lower arch length. Total absence of interdental spacing was found in 4% children. Interdental spacing of the deciduous dentition is present in 96% of Polish children. Children with wider intercanine widths have wider primary spaces in maxilla and wider secondary spaces in mandible.

  11. Polynomial and catenary curve fits to human dental arches.

    PubMed

    Pepe, S H

    1975-01-01

    Polynomial and catenary equations were fit by least square error methods to the dentitions of seven children with "normal" occlusion. Mean and mean square error were then used to analyze accuracy of curve fits and asymmetries of arches. A lack of congruency for the "lines of occlusion" common to the maxilla and mandible suggest that the defining anatomic landmarks are inaccurate. These analyses show that the coefficients of the sixth degree polynomial equations appear to have potential as clinical indicators of arch form and, perhaps, malocclusion.

  12. Reporting of dental status from full-arch radiographs: Descriptive analysis and methodological aspects

    PubMed Central

    Huettig, Fabian; Axmann, Detlef

    2014-01-01

    AIM: To identify standards, how entities of dental status are assessed and reported from full-arch radiographs of adults. METHODS: A PubMed (Medline) search was performed in November 2011. Literature had to report at least one out of four defined entities using radiographs: number of teeth or implants; caries, fillings or restorations; root-canal fillings and apical health; alveolar bone level. Cohorts included to the study had to be of adult age. Methods of radiographic assessment were noted and checked for the later mode of report in text, tables or diagrams. For comparability, the encountered mode of report was operationalized to a logical expression. RESULTS: Thirty-seven out of 199 articles were evaluated via full-text review. Only one article reported all four entities. Eight articles reported at the maximum 3 comparable entities. However, comparability is impeded because of the usage of absolute or relative frequency, mean or median values as well as grouping. Furthermore the methods of assessment were different or not described sufficiently. Consequently, established sum scores turned out to be highly questionable, too. The amount of missing data within all studies remained unclear. It is even so remissed to mention supernumerary and aplased teeth as well as the count of third molars. CONCLUSION: Data about dental findings from radiographs is, if at all possible, only comparable with serious limitations. A standardization of both, assessing and reporting entities of dental status from radiographs is missing and has to be established within a report guideline. PMID:25325067

  13. Transverse dental arch relationship at 9 and 12 years in children with unilateral cleft lip and palate treated with infant orthopedics: a randomized clinical trial (DUTCHCLEFT).

    PubMed

    Noverraz, R L M; Disse, M A; Ongkosuwito, E M; Kuijpers-Jagtman, A M; Prahl, C

    2015-12-01

    A long-term evaluation to assess the transverse dental arch relationships at 9 and 12 years of age in unilateral cleft lip and palate treated with or without infant orthopedics (IO). The hypothesis is that IO has no effect on the transverse dental arch relationship. A prospective two-arm randomized controlled trial (DUTCHCLEFT) in three academic cleft palate centers (Amsterdam, Nijmegen and Rotterdam, the Netherlands). Fifty-four children with complete unilateral cleft lip and palate and no other malformations were enrolled in this evaluation. One group wore passive maxillary plates (IO+) during the first year of life, and the other group did not (IO-). Until the age of 1.5, all other interventions were the same. Hard palate was closed simultaneously with bone grafting according to protocol of all teams. Orthodontic treatment was performed when indicated. The transverse dental arch relationship was assessed on dental casts using the modified Huddart/Bodenham score to measure the maxillary arch constriction at 9 and 12 years of age. No significant differences were found between the IO+ and IO- groups. Differences between the centers increased from 9 to 12 years of age. Transverse dental arch relationships at 9 and 12 years of age do not differ between children with UCLP treated with or without IO. There is no orthodontic need to perform IO as applied in this study in children with UCLP.

  14. Investigation of complete dental arches of 23 patients aged at least 75 years

    PubMed Central

    Volpato, Beniamino; Di Carlo, Stefano; Shahinas, Jorida; Mencio, Francesca; Fusco, Raimondo; Pompa, Giorgio

    2012-01-01

    Summary Numerous factors help to conserve the dentition of elderly patients, such as healthy food habits, a strong physical constitution, and a good quality of life. The aim of this study was to define a model that takes into account the integration of both the structural and functional aspects of a healthy dentition. Twenty-three patients aged at least 75 years were recruited. The patients were required to possess all of their dentition and have no prosthetic rehabilitations and be asymptomatic for temporomandibular joint disorders. Occlusal characteristics were measured and recorded using the criteria adopted by the US National Health and Nutrition Examination Survey: presence or absence of rotation of the upper arches, trend of the occlusal table, and distribution of occlusal contacts during movements. We believe that the following parameters are predictive of a condition of the dental arches’ equilibrium: crowding and disalignment of the teeth, derotated position of the upper arches, absence of the curve of Spee, an occlusal plane trend contrary to spherical theory, and presence of group function on the working side and malocclusion on the nonworking side. We consider that these factors are merely the consequence of correct functioning within the framework of favorable environmental factors. PMID:22545185

  15. Three-dimensional visualisation and analysis of post-operative changes in the size and shape of the dental arch and palate.

    PubMed

    Trefný, P; Tauferová, E; Bálková, S

    2005-01-01

    In craniofacial surgery and orthodontics, three-dimensional computer models of the dental arch and palate have recently entered usage in diagnosis assessment, treatment planning, case presentations and evaluation of treatment progress and outcome. In this contribution, we show how effective visualisation and evaluation of changes in the size and shape of the dental arch and palate in a given patient can be performed using superimposition of two or more 3D computer models that record the condition before and after treatment. We also present a method of three-dimensional measurement of the dental arch and palate suitable for evaluation of treatment results within retrospective and prospective studies in larger samples of subjects.

  16. Human dental arch shape evaluated by euclidean-distance matrix analysis.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G

    1993-04-01

    Form differences between biological structures can be evaluated using several approaches. When landmark data are available, a recently proposed method (euclidean-distance matrix analysis) seems to be able to differentiate between size and shape differences. This method also localizes those areas which differ most between the two structures. We have applied it to analyze the sexual dimorphism in dental arch form in a sample of 50 men and 45 women. Subjects ranged in age between 20 and 27 years, and had sound dentitions. Fourteen landmarks, corresponding to the centers of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were individualized on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed, thus creating four mean form matrices (one for each arch within sex). Gender differences were tested by using euclidean-distance matrix analysis. No significant differences were demonstrated in the shape of arches, while male arches proved to be slightly bigger than female arches.

  17. From classroom teaching to clinical practice: experiences of senior dental students regarding the shortened dental arch concept.

    PubMed

    Khan, Saadika B; Chikte, Usuf M E; Omar, Ridwaan

    2014-06-01

    This study explored the barriers to a meaningful translation of didactic classroom instruction to clinical practice, using the shortened dental arch (SDA) concept as a case study. A combination of survey and individual and group interviews (a mixed-methods approach) was used to collect data related to the SDA. The cohort consisted of senior dental students and their clinical teachers at the University of the Western Cape, South Africa. The response rates were 100 percent for the students (n=73) and 78 percent for the clinical teachers (n=16). Triangulation was employed to eliminate bias and strengthen the reliability of the research. In the quantitative analysis, most students (81 percent) reported having heard about the SDA concept at the university, but their responses revealed an absence of clinical implementation. The students agreed that patients can function adequately with an SDA and agreed with presenting it as a treatment option to patients. In the qualitative analysis, a "change in the clinical requirements," "being empowered by exposing them to SDA literature," and "change in health policies" were recommended measures to increase implementation of the SDA approach clinically. The students were positive about the SDA as a treatment option, but the lack of adequate knowledge and encouragement in clinical implementation was a hindrance to its use.

  18. Comparison of dental arch dimensions in models of preschool children with cleft lip/palate repaired by means of surgery alone versus controls.

    PubMed

    Burhan, Ahmad S; Nawaya, Fehmieh R

    2016-09-01

    Cleft lip and palate (CLP) anomaly is one of the most prevalent congenital defects causing disturbances of dental arch dimensions. This study aimed at investigating differences in these dimensions between preschool children with cleft lip/palate and a matched control group representing healthy individuals with normal occlusion (NO). The sample of this cross-sectional analytical study consisted of 108 plaster models of children aged from 4 to 5.5 years. They were divided into five groups: the cleft lip group, the cleft palate (CP) group, the unilateral cleft lip and palate group, the bilateral cleft lip and palate group, and the NO group. The NO group was used as a control group. All cleft-affected children were treated only with surgery. Dental arch length and widths were measured. The dental arch dimensions of the cleft lip group were nearly similar to those in the controls. Moreover, the mandibular transverse widths of the CP group were close to those in the controls. However, the mandibular arch length and all maxillary dimensions of the CP group were smaller than those in the controls. In the unilateral cleft lip and palate group, the arch lengths in both jaws and the maxillary transverse widths were smaller than those in the controls, whereas the mandibular transverse widths were similar to those in the controls. In the bilateral cleft lip and palate group, the arch lengths in both jaws were close to those in the controls, but both arches were narrower than those in the controls. The various types of CLP were found to be associated with differences in most maxillary and some mandibular arch dimensions. These data can be used for cleft patient counseling and treatment planning.

  19. Pneumatic impression: Improving dental arch impression with an inflatable balloon.

    PubMed

    Gupta, Lokendra

    2016-01-01

    The purpose of this impression technique is to overcome the problem associated with restricted mouth opening in association with high arched palate by employing pneumatic impression technique using latex balloon. A stock tray was modified with auto polymerizing acrylic resin. On the modified tray, a latex balloon was attached with aid of cyanoacrylate. The outlet of the balloon was then connected to a clinical sphygmomanometer bulb with the rubber pipe for air passage which would aid in inflating the balloon. The prepared tray assembly was then equipped for recording the impression. An adequate amount of addition polysiloxane impression material, sufficient to cover the entire area of the balloon was loaded onto the tray. The balloon was then inflated with the help of a sphygmomanometer bulb which transferred the air only in one direction. On completion of setting time of the impression material, the air pressure was relieved by deflating of balloon which helped in the easy removal of the impression. The impression was subsequently removed from the oral cavity and disinfected. This novel technique was helpful for recording impression in patients presenting with restricted mouth opening and high arched palate.

  20. Assessment of dental arches in patients with Class II division 1 and division 2 malocclusions using 3D digital models in a Syrian sample.

    PubMed

    Hajeer, M Y

    2014-06-01

    (1) to evaluate the applicability of using 3D digital models in the assessment of Class II Division 1 (Cl II-1) and Class II Division 2 (Cl II-2) malocclusion in a Syrian sample, (2) to detect any significant differences between the two groups in tooth and arch widths, anterior (ABR) and overall Bolton ratios, PAR Index, and (3) to detect any gender differences in these variables. observational, cross-sectional study for descriptive and analytical purposes at the Orthodontic Dept., University of Al-Baath Hamah Dental School, Hamah, Syria. A disproportionate multi-stratified random sampling was employed to select 36 Cl II-1 and 36 Cl II-2 patients (female-to-male ratio was 1:1 in each group). 3D digital models (O3DM) with a dedicated programme were used to measure dental arch variables. Significant differences were observed between the two groups in the mesiodistal widths of some teeth but not in the dental arch widths. The prevalence of 'discrepancy cases' in Anterior Bolton Ratios (ABRs) was 33.33% and 41.67% in Cl II1 and Cl II2 groups, respectively. The mean PAR Index score was 25.36 and 20.82 for Cl II1 and Cl II2 groups, respectively (p=0.009). (1) 3D digital models enabled fast, accurate and reliable measurements of dental arch characteristics in patients with Class II malocclusion. (2) Insignificant differences between Cl II1 and Cl II2 patients were observed regarding Bolton's ratios and transverse arch measurements. (3) Sexual dimorphism was observed in mesiodistal tooth widths and in dental arch widths, but not in Bolton's ratios and PAR Index scores.

  1. Evaluation of maxillary arch dimensions and palatal morphology in mouth-breathing children by using digital dental casts.

    PubMed

    Lione, Roberta; Buongiorno, Marco; Franchi, Lorenzo; Cozza, Paola

    2014-01-01

    The aim of the present study was to analyze the variations of maxillary arch size and of palatal morphology in subjects with prolonged mouth-breathing due to allergic rhinitis when compared with a control group with normal breathing pattern by using a three-dimensional analysis on digital casts. 26 Caucasian children (19 females and 7 males) with a mean age of 8.5 years (SD 1.6 years) were selected according to the following criteria: mouth-breathing pattern due to allergic rhinitis, early mixed dentition, skeletal Class I relationship and prepubertal stage of cervical vertebral maturation. The study group was compared with a control group of 17 nasal breathing subjects (9 females; 8 males, mean age 8.5 years SD 1.7 years). For each subject an initial dental cast was taken and the upper arch was scanned by using a tridimensional scanner. On each digital model linear measurements were performed to analyze maxillary arch dimensions and palatal morphology. Significant between-group differences were tested with the Student t-test (p<0.05). the transverse dimension of the upper arch was significantly smaller in subjects of the study group thus confirming the influence of oral breathing on skeletal development with a significant constriction of the whole palate. The study group showed a higher and sharper palatal vault at the level of second deciduous molars and of first permanent molars. Children with mouth-breathing pattern showed a significant constriction of the maxillary arch and an increased palatal height when compared with subjects with normal breathing pattern. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. [Treatment using the Lehman apparatus in patients with malocclusion in light of teleradiologic tests and dental arch measurements].

    PubMed

    Bielawska, Hanna

    2002-01-01

    The aim of this study was to assess the usefulness of Lehman's appliance for the management of distocclusion and to establish indications and contraindications to its use. The mean duration of treatment was also determined and compared to such in similar form of malocclusion treated with other types of functional appliances. Linear measurements were performed on dental plaster casts before and after treatment. Cephalometric analysis served to establish the mechanism of Class II correction (skeletal or dentoalveolar) and to reveal any increase in mandibular length caused by Lehman's appliance. The material consisted of thirty-three Class II patients (18 girls and 15 boys), aged 9 to 15 years, treated successfully with Lehman's appliance for distocclusion. Dental plaster casts and lateral cephalograms were obtained at the beginning and end of treatment. Improvement in occlusal relationship in the molar, canine and incisor segments was the result of dental and skeletal changes. Metric analysis of dental casts before and after treatment showed that active treatment was associated with an increase in transversal dimensions of the upper arch ranging from 1.8 to 2.4 mm. Overbite and overjet decreased considerably. Anterior length of upper arch was reduced significantly in boys only and was accompanied by distraction and transition from a V-shaped to U-shaped type of arch. These changes helped to harmonize transversal dental relationship of both arches and improved conditions for functional skeletal base adaptation. Treatment with Lehman's appliance improved the intermaxillary relationship and led to a decrease in the ANB angle attributable to a change in the SNA angle in girls and the SNB angle in boys. The mandibular reaction in girls with Class II/2 was interesting: the SNB angle increased considerably, indicating "unblocking" of the mandible. Changes in the vertical skeletal relationship were limited to a minor reduction in the index. Maxillary incisors moved little

  3. Dental arch width, overbite, and overjet in a Finnish population with normal occlusion between the ages of 7 and 32 years.

    PubMed

    Heikinheimo, Kaisa; Nyström, Marjatta; Heikinheimo, Tuomas; Pirttiniemi, Pertti; Pirinen, Sinikka

    2012-08-01

    The aims of the present study were to provide data on growth changes in the dental arches from age 7 to 32 in Finns with untreated normal Angle Class I occlusions. The material consisted of 33 series of dental casts of 18 women and 15 men. The subjects had been examined and study models taken at the ages of 7, 10, 12, 15, and 32. Dental arch width, overbite, and overjet were measured. Our longitudinal findings show that both the dental arches of young adults are slightly narrowed from adolescence to 32 years of age. All increases in width dimensions took place before 15 years of age. The means of the changes were mostly small, in the order of 0.5 to a few millimetres. Variability in age changes was considerable. In both genders, each variable increased in some subjects and decreased in others during every age interval. Differences between growth changes in the mesial, distal, and gingival intermolar widths indicate that both the maxillary and the mandibular first molars rotate mesiolingually and that the maxillary first molars also become more upright during late occlusal development. We expect the present findings of the changes occurring in the arch dimensions of subjects with untreated normal occlusions to help clinicians in following up occlusal development, choosing an optimal treatment time, and making orthodontic treatment and retention plans. However, because of the wide variability, accurate prediction of future development cannot be made on the individual level.

  4. Relationship of Inter-Condylar Distance With Inter-Dental Distance Of Maxillary Arch and Occlusal Vertical Dimension: A Clinical Anthropometric Study

    PubMed Central

    Gupta, Renu; Meenakshi, A; Kumar, Sandeep; Hota, Sadananda; Rawat, Pratibha

    2014-01-01

    Aim: To find out the anthropometric relationship of Inter-condylar distance to Inter-canine and Inter-molar distance of maxillary arch and occlusal vertical dimension in dentate individuals of South Indian population. Materials and Methods: A total number of 120 dentate individuals were randomly equally divided into Group A and Group B. According to the face form, each Group was again subdivided into four subgroups. Subgroup A1 and B1 contained Square face form, Subgroup A2 and B2 Tapered, Subgroup A3 and B3 Square tapered and Subgroup A4 and B4 Ovoid face form. The ratio of ICD to U3, U6 and OVD of Group A individuals were applied to the Group B individuals with similar face forms and the clinical significance of the ratios were evaluated. Results: No significant difference (p-value=0.841) was observed in the ratio of U6 to ICD (U6/ICD) in all the face forms. A significant difference (p-value = 0.010) in the mean value was observed when the ratio of OVD to ICD (OVD/ICD) was compared between the squared tapered face form of Group A (0.60 ± 0.01) and Group B (0.06±0.03). A significant difference (p value = 0.007) was observed between the measured (62.47 ±2.77) and calculated (64.99±2.61) values of OVD in square taper face form. Conclusion: In south Indian population, ICD can be used as a reliable guide line to determine the bucco-palatal position of maxillary first molar irrespective of the face forms. PMID:25654029

  5. Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch

    PubMed Central

    Wu, Jun; Zheng, Qian; Shi, Bing; Meng, Tian; Wang, Yan; Li, Sheng; Liao, Li-shu

    2008-01-01

    Objective: This study aimed to explore the effects of different types of palatal lateral excisions on the growth and development of the maxilla and dental arch, and to investigate the underlying mechanisms. Methods: A total of 112 3-week-old Sprague-Dawley (SD) male rats were randomly divided into a control and 3 experimental groups: the mucoperiosteal denudation group, the mucosal flap excision group, and the periosteum excision group. In the experimental groups, bilateral mucoperiosteal, mucosal flap and periosteum were excised respectively in the lateral one half of the palate. Four rats in each group were randomly chosen for sacrifice every two weeks. The maxilla was dissected following the excision. The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases. At the same time, 12 animals in each group were sequentially injected with calcein every two weeks. Three animals in each group, whose fluorescent labeling was used, were sacrificed for investigating bone formation at Week 8 following injection. Results: (1) Each experimental group presented the constriction of the maxilla and dental arch. The upper first molars in the experimental groups inclined medially. The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group. The indices of the mucosal flap excision group, which retained the structures of the periosteum layer, had the most approximate values to the control group; (2) Different histological changes among the experimental groups were detected. The fibers penetrated into the palatal bone as Sharpey’s fibers in the mucoperiosteal denudation group. The pattern of bone deposition was the bundle type. Sharpey’s fibers were not found in the mucosal flap and periosteum excision groups and the depositions of palatal bone were the lamellar type as those in the control group; (3) The rates of bone deposition in the experimental groups

  6. Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch.

    PubMed

    Wu, Jun; Zheng, Qian; Shi, Bing; Meng, Tian; Wang, Yan; Li, Sheng; Liao, Li-shu

    2008-08-01

    This study aimed to explore the effects of different types of palatal lateral excisions on the growth and development of the maxilla and dental arch, and to investigate the underlying mechanisms. A total of 112 3-week-old Sprague-Dawley (SD) male rats were randomly divided into a control and 3 experimental groups: the mucoperiosteal denudation group, the mucosal flap excision group, and the periosteum excision group. In the experimental groups, bilateral mucoperiosteal, mucosal flap and periosteum were excised respectively in the lateral one half of the palate. Four rats in each group were randomly chosen for sacrifice every two weeks. The maxilla was dissected following the excision. The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases. At the same time, 12 animals in each group were sequentially injected with calcein every two weeks. Three animals in each group, whose fluorescent labeling was used, were sacrificed for investigating bone formation at Week 8 following injection. (1) Each experimental group presented the constriction of the maxilla and dental arch. The upper first molars in the experimental groups inclined medially. The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group. The indices of the mucosal flap excision group, which retained the structures of the periosteum layer, had the most approximate values to the control group; (2) Different histological changes among the experimental groups were detected. The fibers penetrated into the palatal bone as Sharpey's fibers in the mucoperiosteal denudation group. The pattern of bone deposition was the bundle type. Sharpey's fibers were not found in the mucosal flap and periosteum excision groups and the depositions of palatal bone were the lamellar type as those in the control group; (3) The rates of bone deposition in the experimental groups decreased compared with the control

  7. [Biomechanical study on dento-alveolar arch forces].

    PubMed

    Onu, Brînduşa; Burlui, V

    2009-01-01

    This study has two major objectives. The first one is to draw attention in an original device especially conceived and designed to measure bite force; the second purpose of the study is represented by proper measurements of individual bite force during bilateral clenching for two lots of patients using this device and comparing the outcomes to those of other similar studies, in order to prove its practical utility. 62 young (20-35 years of age) healthy patients were tested: 35 fully dentured subjects in control group and 27 subjects with various single unit treated edentation, in test group. The two potentiometers from the lateral side of the device are connected to a computer which would measure, register and interpret the outcomes during three different sessions of clenching for each patient. Measured values showed that the mean maximum bilateral bite force in patients with no edentation was, in all cases, higher than in patients with single unit treated edentation for all three sessions. Because the device allows simultaneous bilateral registration of the bite force, during the same session, it is obvious that it can measure also the asymmetry between left and right dental hemi-arches. Therefore, in control group, mean values found in left side were higher (369.36N - 399.75N) than right side (352.18N - 392.15N); an opposite situation was found in test group: higher values were found in right side (313.75N - 329.43N) comparing to left side (310.54N -321.53N). The device proved to be usefull not only for measuring bite force in one region of dental arches, but it is designed to simultaneous register parameters from various regions; the values obtained in this study are similar to those reported by others authors who used more sophisticated devices, so that this simple device proves its usefulness.

  8. A new operative method for obtaining full-arch prostheses for immediate loading dental implants.

    PubMed

    de Mello, Guilherme Paulo Scarpel; Mello, Elaine Duarte Artuso de; Corazza, Pedro Henrique

    2017-04-01

    Implant supported full-arch immediate prosthesis (also called the immediate Brånemark protocol) revolutionized dental clinical practice due to the aesthetic/functional benefits it offers to the patient. This work presents a simplified and efficient technique for implant supported full-arch immediate prosthesis fabrication. After diagnosing the necessity of the protocol, the implants were installed with a minimum torque of 35Ncm. For implant impression, the use of previously prepared castable cylinders (dispensing with impression posts), and a U-shaped acrylic (Mello technique) generated a cast without distortion. The Brånemark protocol was fabricated on this cast without the metal test specimen. The simplified technique proposed in this article for Brånemark protocol fabrication seemed to be effective. Copyright © 2016 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  9. Dental arch relationship in children with complete unilateral cleft lip and palate following one-stage and three-stage surgical protocols.

    PubMed

    Fudalej, Piotr; Katsaros, Christos; Bongaarts, Catharina; Dudkiewicz, Zofia; Kuijpers-Jagtman, Anne Marie

    2011-08-01

    The objective of this study is to compare dental arch relationship following one-stage and three-stage surgical protocols of unilateral cleft lip and palate. Dental casts of 61 children (mean age, 11.2 years; SD, 1.7), consecutively treated in one center with one-stage closure of the complete cleft at 9.2 months (SD, 2.0), were compared with a sample of 97 patients (mean age, 8.7 years; SD, 0.9), consecutively treated with a three-stage protocol including delayed hard palate closure in another center. The dental casts were assigned random numbers to blind their origin. Four raters graded dental arch relationship and palatal morphology using the EUROCRAN index. The strength of agreement of rating was assessed with kappa statistics. Independent t tests were run to compare the EUROCRAN scores between one-stage and three-stage samples, and Fisher's exact tests were performed to evaluate differences of distribution of the EUROCRAN grades. The intra- and inter-rater agreement was moderate to very good. Dental arch relationship in the one-stage sample was less favorable than in three-stage group (mean scores, 2.58 and 1.97 for one-stage and three-stage samples, respectively; p < 0.000). Palatal morphology in the one-stage sample was more favorable than in the three-stage group (mean scores, 1.79 and 1.96 for one-stage and three-stage samples, respectively; p = 0.047). The dental arch relationship following one-stage repair was less favorable than the outcome of three-stage repair. The palatal morphology following one-stage repair, however, was more favorable than the outcome of three-stage repair.

  10. Evaluation of continuous arch and segmented arch leveling techniques in adult patients--a clinical study.

    PubMed

    Weiland, F J; Bantleon, H P; Droschl, H

    1996-12-01

    The purpose of this study was to compare the efficacy of overbite correction achieved by a conventional continuous arch wire technique and the segmented arch technique as recommended by Burstone. The sample comprised 50 adult patients (age 18 to 40 years) with deep bites. Twenty-five patients were treated with a continuous arch wire technique (CAW); in the second half of the sample, the segmented arch technique (Burstone) was used for correction of the vertical malocclusion. Lateral cephalograms and plaster cast models taken before and immediately after treatment were evaluated. Statistical analysis was performed on the collected data. The results showed that both techniques produced a highly significant overbite reduction (CAW: -3.17 mm, p < 0.001; Burstone: -3.56 mm, p < 0.001). The CAW group showed an extrusion in the molar area with subsequent posterior rotation of the mandible (6occl-ML: +1.30 mm; 6occl-NSL: +1.63 mm; ML/NSL: +1.94 degrees, all p < 0.001). The Burstone group, however, showed overbite reduction by incisor intrusion without any substantial extrusion of posterior teeth (upper 1-NSL: -1.50 mm; lower 1-ML: -1.72 mm; both p < 0.001). As a consequence, no significant posterior rotation of the mandible took place (ML/NSL: +0.52 degrees, n.s.). It is concluded that in adult patients the segmented arch technique (Burstone) can be considered as being superior to a conventional continuous arch wire technique if arch leveling by incisor intrusion is indicated.

  11. Correlation between interdental occlusal plane and plantar arches. An EMG study.

    PubMed

    Valentino, B; Melito, F; Aldi, B; Valentino, T

    2002-01-01

    The Authors carried out an experimental study on a homogeneous group of young people to provide evidence of functional correlation among masticatory muscles and, indirectly, between changes to the interdental occlusal plane and modifications of the plantar arches due to talipes valgus and flat foot. In the two analysed conditions, the masticatory muscles undergo different functional alterations. This is due to the fact that the mechanoreceptors in the tendons of the muscles governing the plantar arch configuration are stimulated in different ways during the activation of long osteoarthromuscular chains. Dental specialists will have to take these correlation into account when diagnosing TMJ disorders.

  12. Evaluation of facial morphology and sagittal relationship between dental arches in primary and mixed dentition.

    PubMed

    Traldi, Aline; Valdrighi, Heloísa Cristina; de Souza, Luciane Zanin; Vedovello, Silvia Amélia Scudeler

    2015-01-01

    To assess facial morphology (Pattern) and sagittal relationship between dental arches (Class), and establish a potential association between them and the variables sex, age and ethnicity, among schoolchildren aged between 4 and 9 years old (mean age of 6.7 years) in primary and mixed dentitions. The sample comprised 875 children (457 males and 418 females) attending schools in Descalvado, São Paulo, Brazil. An attempt was made with a view to establish a potential association between children's morphological features with sex, age and ethnicity. Descriptive analysis revealed a predominance of facial Pattern I (69.9 %) and Class I (67.4 %). Statistical tests (p < 0.001) showed that Class I was more frequent among Pattern I children, whereas Class II prevailed among Pattern II, and Class III was frequent among Pattern I and III children. Ethnicity was the only variable associated with facial pattern. Results suggest that facial pattern and sagittal relationship between dental arches tend to be correlated. Ethnicity was associated with facial pattern, with Pattern I being the most recurrent among Caucasians and facial Pattern II being recurrent among Afro-descendant subjects.

  13. Evaluation of facial morphology and sagittal relationship between dental arches in primary and mixed dentition

    PubMed Central

    Traldi, Aline; Valdrighi, Heloísa Cristina; de Souza, Luciane Zanin; Vedovello, Silvia Amélia Scudeler

    2015-01-01

    OBJECTIVE: To assess facial morphology (Pattern) and sagittal relationship between dental arches (Class), and establish a potential association between them and the variables sex, age and ethnicity, among schoolchildren aged between 4 and 9 years old (mean age of 6.7 years) in primary and mixed dentitions. METHODS: The sample comprised 875 children (457 males and 418 females) attending schools in Descalvado, São Paulo, Brazil. An attempt was made with a view to establish a potential association between children's morphological features with sex, age and ethnicity. RESULTS: Descriptive analysis revealed a predominance of facial Pattern I (69.9 %) and Class I (67.4 %). Statistical tests (p < 0.001) showed that Class I was more frequent among Pattern I children, whereas Class II prevailed among Pattern II, and Class III was frequent among Pattern I and III children. Ethnicity was the only variable associated with facial pattern. CONCLUSIONS: Results suggest that facial pattern and sagittal relationship between dental arches tend to be correlated. Ethnicity was associated with facial pattern, with Pattern I being the most recurrent among Caucasians and facial Pattern II being recurrent among Afro-descendant subjects. PMID:26352847

  14. Clinical Evaluation of Different Pre-impression Preparation Procedures of Dental Arch

    PubMed Central

    Arora, Nitin; Arora, Monika; Gupta, Naveen; Agarwal, Manisha; Verma, Rohit; Rathod, Pankaj

    2015-01-01

    Background: Bubbles and voids on the occlusal surface impede the actual intercuspation and pre-impression preparation aims to reduce the incidence of air bubbles and voids as well as influences the quality of occlusal reproduction and actual clinical intercuspation in the articulator. The study was undertaken to determine the influence of different pre-impression preparation procedures of antagonistic dental arch on the quality of the occlusal reproduction of the teeth in irreversible hydrocolloid impressions and to determine most reliable pre-impression preparation method to reduce the incidence of air bubbles. Materials and Methods: A total of 20 subjects were selected having full complement of mandibular teeth from second molar to second molar with well demarcated cusp height. 200 impressions were made with irreversible hydrocolloid material. The impressions were divided into five groups of 40 impressions each and each group had one specific type of pre-impression preparation. All the impressions were poured in die stone. A stereomicroscope with graduated eyepiece was used to count the number of bubbles on the occlusal surface of premolars and molars. The mean and standard deviations were calculated for each group. Mann–Whitney U-test was applied to find the significant difference between different groups. Results: Least bubbles were found in the group in which oral cavity was dried by saliva ejector and fluid hydrocolloid was finger painted onto the occlusal surfaces immediately before the placement of impression tray in the mouth. Conclusion: It was found that finger painting the tooth surfaces with fluid hydrocolloid immediately before the placement of loaded impression tray in the mouth was the most reliable method. The oral cavity can be cleared more easily of excess saliva by vacuum suction rather than by use of an astringent solution. PMID:26229376

  15. Comparison of two treatment protocols in children with unilateral complete cleft lip and palate: Tridimensional evaluation of the maxillary dental arch.

    PubMed

    Jorge, Paula Karine; Gnoinski, Wanda; Vaz Laskos, Karine; Felício Carvalho Carrara, Cleide; Gamba Garib, Daniela; Okada Ozawa, Terumi; Andrade Moreira Machado, Maria Aparecida; Pinelli Valarelli, Fabrício; Oliveira, Thais Marchini

    2016-09-01

    The aim of this study was to evaluate the dimensional alterations of the maxillary dental arches after lip repair in children with unilateral complete cleft lip and palate of two different protocols. The sample was composed of 94 digital models and divided in two groups: Group I - 23 children, (protocol 1) - with presurgical orthopedic intervention: Hotz plate; Group II - 24 children, (protocol 2) - without presurgical orthopedic intervention. The three dimensional images of the maxillary arch were obtained before lip repair (stage 1) and at approximately 1 year of age (stage 2). Interstages changes for each group were evaluated using dependent t test and Wilcoxon test, and in the intergroup were used independent t test, and Mann-Whitney test. The comparison of the dimensional alterations of dental arches between the two protocols exhibited differences: in the stage 1, the intercanine was smaller in Group II; in the stage 2, the anterior cleft width, the intercanine and the anteroposterior cleft were smaller in Group II. The results reported here suggest that the use of infant orthopedic plate as applied in protocol 1 may favor correct arch form establishment in infants with unilateral complete cleft lip and palate. Copyright © 2016. Published by Elsevier Ltd.

  16. Effect of implant-supported prosthesis on the bite force and masticatory efficiency in subjects with shortened dental arches.

    PubMed

    Meena, A; Jain, V; Singh, N; Arora, N; Jha, R

    2014-02-01

    The aim of the study was to assess changes in bite force and masticatory efficiency in shortened dental arch (SDA) subjects rehabilitated with implant-supported restoration for 1st molar. Ten SDA subjects with bilaterally missing mandibular molars (experimental group) were recruited. In each subject, one tapered threaded implant was placed bilaterally in 1st mandibular molar region and restored. Masticatory efficiency was evaluated objectively by measuring the released dye from chewed raw carrots, with a 'spectrophotometer' at 530 nm preoperatively and at 3 months after restoration. Bite force was evaluated using 'bite force measuring appliance' preoperatively, at 6 weeks and at 3 months after restoration. Ten completely dentate-matched subjects (in terms of age, sex, height and weight) acted as control. The results revealed that as compared with the control group, the experimental group showed significantly less (P < 0.05) mean maximum bite force at pre-restoration and at 6 weeks after restoration. Although at 3 months the mean maximum bite force value was less than the control group but the mean difference was statistically insignificant. The mean difference of masticatory efficiency between control and experimental group was statistically significant (P < 0.05) before restoration, but was statistically insignificant at 3 months after restoration. Thus it was concluded that after the restoration of mandibular arch with implant-supported prosthesis, both bite force and masticatory efficiency of all SDA subjects increased and were comparable to that of matched completely dentate subjects after 3 months.

  17. [A new method to orthodontically correct dental occlusal plane canting: wave-shaped arch].

    PubMed

    Zheng, X; Hu, X X; Ma, N; Chen, X H

    2017-02-18

    To introduce a technique of second order wave-shaped arch wire to orthodontically treat dental occlusal plane canting (DOPC) with left-right interactive anchorage, and to test its clinical efficacy. Among the permanent dentition malocclusion patients who showed no obvious facial asymmetry, we screened for patients who showed anterior occlusal plane canting (AOPC) after routine orthodontic examination, treatment planning, MBT fixed appliance installation and serial arch wires alignment. Each patient had been clinically appraised in frontal view by 2 orthodontists and the patient him/herself; if all 3 agreed that the AOPC was obvious, the patient was included. By this means, we included 37 patients, including 10 males and 27 females; the average age was (21.9±5.2) years. To correct AOPC, opposite direction equal curvature second order rocking-chair curve was bent on each side of 0.46 mm×0.56 mm stainless steel edgewise wire. With reference to normal occlusal plane, a curve toward the occlusal surface was made to extrude under-erupted teeth on one side while a curve toward the gingiva was made to intrude over-erupted teeth on the other side, so that the arch wire was made into a wave shape in vertical dimension. Before and after application of wave-shaped arch wire, frontal facial photographs were taken when the patient's mouth was open slightly with lips retracted to show anterior occlusal plane (AOP) clearly. An AOP was constructed by connecting the center of the slot in the medial edge of canine bracket on each side in the photograph. The angles between the bipupillary plane(BPP) and the constructed AOP were measured in ImageJ1-48v software and the angle differences before and after treatment were compared with paired Wilcoxon test in SPSS 10.0 software. The wave-shaped arch could correct AOPC effectively in 3 to 10 months time with an average of 5.5±1.7 months; the angles between AOP and BBP before treatment ranged from 2.90° to 6.12° with a median of 4.01

  18. Dental arch changes from 22 to 43 years of age: are they different in individuals with high versus low mandibular plane angle?

    PubMed

    Bondevik, Olav; Espeland, Lisen; Stenvik, Arild

    2015-08-01

    To investigate whether individuals with high and low mandibular plane angles, respectively, have different patterns of long-term dental arch changes in adulthood. The material comprised 16 low-angle (≤ 24.4 degree) and 10 high-angle individuals (≥38.7 degree). Mean age was 22.7 years when the first recordings were made (T1), and new recordings were made 10 (T2) and 20 (T3) years later. The individuals were orthodontically untreated except for three who had been out of retention for more than 5 years before T1. Lateral cephalograms and study casts were obtained on all three occasions. For the total observation period, the greatest mean changes were observed as a 1mm decrease of lower intercanine width and arch depths in both groups. Intermolar widths increased less than 0.5mm. Upper and lower crowding increased in the range of 0.5-0.7mm in the two groups. Only small changes occurred in overjet and overbite. Differences between groups were not significant except for lower anterior arch depth which decreased more in the low-angle group, and overjet which increased in the high- and decreased in the low-angle group. During both periods the changes were generally in the same direction. Changes in dental arch dimensions from third to fifth decade of life are small and generally similar in individuals with high versus low mandibular plane angles. The changes are for most variables in the same direction in the two periods examined. The only significant differences between the groups are the changes in lower arch depth and overjet. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  19. Systematic review of short- (5-10 years) and long-term (10 years or more) survival and success of full-arch fixed dental hybrid prostheses and supporting implants.

    PubMed

    Kwon, TaeHyun; Bain, Paul A; Levin, Liran

    2014-10-01

    The aim of this systematic review was to investigate the short-term (5-10 year mean follow-up) and long-term (10 year or more) survival and success of fixed full arch dental hybrid prosthesis and supporting dental implants. Studies reporting interventions with full-arch fixed dental hybrid prostheses were identified by searching PubMed/Medline (NCBI), Web of Science (Thomson Reuters), the Cochrane Register of Controlled Clinical Trials (EBSCO), and Dentistry and Oral Sciences Source (DOSS; EBSCO) from the earliest available dates through July 17, 2013. Through a series of review process by two examiners, potentially qualifying studies were identified and assessed with respect to the inclusion criteria. A total of 18 studies were included for the quality assessment and the systematic review. Within the limitation of available studies, high short-term survival rates of full arch fixed dental hybrid prostheses (93.3-100%) and supporting implants (87.89-100%) were found. However, the availability of studies investigating long-term outcomes seemed scarce. Furthermore, the included studies were subjected to potential sources of bias (i.e. publication, reporting, attrition bias). Despite seemingly high short-term survival, long-term survival of implant supported full arch fixed dental hybrid prosthesis could not be determined due to limited availability of true long-term studies. Although it may be a valuable option for a patient with a completely edentulous ridge(s), the strategic removal of teeth with satisfactory prognosis for the sake of delivering an implant supported full-arch dental hybrid prosthesis should be avoided. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Immediate loading of immediate mandibular implants with a full-arch fixed prosthesis: a preliminary study.

    PubMed

    Peñarrocha, Miguel; Boronat, Araceli; Garcia, Berta

    2009-06-01

    To determine the survival of immediate dental implants with immediate loading in the partially edentulous mandible, by use of a full-arch screw-retained provisional restoration. Patients who were partially edentulous in the mandible with indications for extraction of the remaining teeth and with a minimum follow-up of 12 months after implant placement were included in the study. They were treated in chronologic order by the insertion of 6 Defcon dental implants (Impladent, Sentmenat, Spain) subjected to immediate loading (4 interforaminal and 2 posterior placements). Implants with a minimum primary stability of 60 implant stability quotient were loaded. All resin screw-retained prostheses were inserted and loaded with fully functional occlusion within 24 hours of implant placement. Eleven patients were treated with immediate implants, although 2 patients were excluded from the study for having an implant stability quotient value below 60 in at least one of the implants after surgery and did not undergo restoration with immediate loading. Fifty-four implants were placed in 9 partially edentulous patients with immediate loading with a full-arch screw-fixed prosthesis. The patients wore this provisional prosthesis during the healing period (2 months) without complication and with a high level of comfort. The survival rate of the implants was 100% at 12 months of follow-up. Immediate mandibular loading with immediate full-arch implant-supported and screw-retained restorations is a viable treatment alternative, yielding a 100% success rate in this small series of patients.

  1. Pathognomonic features of Angle's Class II division 2 malocclusion: A comparative cephalometric and arch width study.

    PubMed

    Prasad, Singamsetty E R V; Indukuri, Ravikishore Reddy; Singh, Rupesh; Nooney, Anitha; Palagiri, Firoz Babu; Narayana, Veera

    2014-12-01

    A thorough knowledge of the salient features of malocclusion helps the clinician in arriving at a proper diagnosis and treatment plan, and also to predict the prognosis, prior to the onset of treatment process. Among the four classes of Angle's classification of malocclusion, Class II division 2 occurs with the least frequency. There is still continuing debate in the literature whether the Class II division 2 patients ascribe the pathognomonic skeletal and dental features. The aim of this study is to describe the unique features of Angle's Class II division 2 malocclusion to differentiate it from Angle's Class II division 1 malocclusion. A total of 582 pre-treatment records (study models and cephalograms), with the age of patients ranging from 15 to 22 years, were obtained from the hospital records of Vishnu Dental College, Bhimavaram and Geetam's Dental College, Visakhapatnam. Out of these, 11 pre-treatment records were excluded because of lack of clarity. In the rest of the sample, 283 were Class II division 1 and 288 were Class II division 2. The lateral cephalograms were analyzed by using digiceph and the arch width analysis was done based on the anatomical points described by Staley et al. and Sergl et al. An intergroup evaluation was done by using unpaired Student's "t" test. The skeletal vertical parameters, dental parameters, and the maxillary arch width parameters revealed a statistically significant difference between the two groups of malocclusion. Angle's Class II division 2 malocclusion has a pronounced horizontal growth pattern with decreased lower anterior facial height, retroclined upper anteriors, and significantly increased maxillary arch width parameters.

  2. Reconstruction of a collapsed dental arch in a patient with severe periodontitis.

    PubMed

    Nakamura, Yoshiki; Gomi, Kazuhiro; Oikawa, Takashi; Tokiwa, Hajime; Sekiya, Toshiko

    2013-05-01

    This case report describes the significance of orthodontic treatment in reconstruction of a collapsed dental arch and a malocclusion associated with severe periodontitis. A Japanese man (age, 40 years 7 months) had an anterior crossbite, a collapsed occlusion, and severe periodontitis. Orthodontic treatment included the following steps: (1) correction of the anterior crossbite, labial movement of the maxillary incisors, and intrusion and retraction of the mandibular incisors; (2) correction of the posterior crossbite on the left side, buccal movement of the maxillary left canine and first premolars, and intrusion and retraction of the mandibular first premolar into the space of the mandibular left canine; (3) correction of the crowding of the mandibular right buccal segment and alignment of the teeth after extraction of the mandibular right first molar with a periapical lesion; and (4) improvement of the occlusion, with reconstruction of an acceptable occlusion. When combined with restorative and prosthodontic treatment, a fairly good occlusion was obtained. Reevaluation of the treatment after 11 years showed that the occlusion and periodontal condition were maintained well without deepening of the pockets and further bone loss. Orthodontic treatment with a systematic approach helped to recover the occlusion and prevented the recurrence of periodontitis by acquiring a good oral environment and motivating the patient to maintain oral health. Copyright © 2013 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  3. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique.

    PubMed

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan; Kim, Hae-Young

    2014-03-01

    This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models.

  4. Bimaxillary full arch fixed dental implant supported treatment for a patient with renal failure and secondary hyperparathyroidism and osteodystrophy.

    PubMed

    Flanagan, Dennis; Mancini, Mark

    2015-04-01

    A long-term dialysis patient with end-stage renal disease (ESRD) also referred to as chronic kidney disease (CKD) due to IgA nephropathy complicated by severe secondary hyperparathyroidism and renal osteodystrophy was successfully treated with dental implant-supported fixed prostheses. Phosphate binders, vitamin D, calcium cinacalcet calcimimetic therapy, and dialysis 3 times weekly had been instituted with standard divalent ion serum assessments. Successful control of the patient's secondary hyperparathyroidism was achieved. Long and wide diameter implants were used with an anterior guidance occlusion scheme to reduce the per-square-millimeter off-axial implant force delivered to the bone. Patients with ESRD and renal osteodystrophy may be successfully surgically and prosthetically treated with long wide dental implants supporting fixed full arch splinted dental prostheses with an appropriate occlusal scheme.

  5. Intra-arch dimensional measurement validity of laser-scanned digital dental models compared with the original plaster models: a systematic review.

    PubMed

    De Luca Canto, G; Pachêco-Pereira, C; Lagravere, M O; Flores-Mir, C; Major, P W

    2015-05-01

    A systematic review was undertaken to evaluate the validity of intra-arch dimensional measurements made from laser-scanned digital dental models in comparison with measurements directly obtained from the original plaster casts (gold standard). Finally included articles were only those reporting studies that compared measurements from digital models produced from laser scanning against their plaster models. Measurements from the original plaster models should have been made using a manual or digital caliper (gold standard). Articles that used scans from impressions or digital photographs were discarded. Detailed individual search strategies for Cochrane, EMBASE, MEDLINE, PubMed, and LILACS were developed. The references cited in the selected articles were also checked for any references that could have been missed in the electronic database searches. A partial gray literature search was undertaken using Google Scholar. The methodology of selected studies was evaluated using the 14-item quality assessment tool for diagnostic accuracy studies (QUADAS). Only 16 studies were finally included for the qualitative/quantitative synthesis. The selected studies consistently agree that the validity of measurements obtained after using a laser scanner from plaster models is similar to direct measurements. Any stated differences would be unlikely clinically relevant. There is consistent scientific evidence to support the validity of measurements from digital dental models in comparison with intra-arch dimensional measurements directly obtained from them.

  6. Dental arch relationship in 5-year-olds with complete unilateral cleft lip and palate after early alveolar bone grafting.

    PubMed

    Offert, B; Pazera, P; Janiszewska-Olszowska, J; Hozyasz, K; Katsaros, C; Fudalej, P S

    2012-05-01

    To evaluate dental arch relationship in preschoolers with unilateral cleft lip and palate after early alveolar bone grafting (ABG). Three raters blindly assessed the dental arch relationship with the GOSLON Yardstick (using a 5-point scale, from 1--very good to 5--very poor outcome) in Early-grafted group (27 boys and 15 girls; mean age = 5.2 years, SD 0.5) and Non-grafted group (17 boys and 12 girls; mean age = 5.8 years, SD 0.8). The groups differed regarding the age when ABG was performed: between 2 and 4 years (mean = 2.4, SD 0.6) in the Early-grafted group and after 9 years in the Non-grafted group. The strength of agreement of rating was evaluated with kappa statistics. The intra- and inter-rater agreement was high (κ > 0.800). The mean GOSLON score in the Early-grafted group was 2.72 and in the Non-grafted group -2.64. The distribution of the GOSLON grades in the Early-grafted group was: 54.8% had a score 1 or 2, 23.8%--3, and 21.4%--4 or 5; in the Non-grafted group, 38.0% subjects scored 1 or 2, 41.4%--3, and 20.6%--4 or 5 (p = 0.023). Early alveolar bone grafting carried out between the ages of 2 and 4 years was not found to negatively affect dental arch relationship by the age of 5 years. However, it is possible that such a negative effect could be found if a longer observation period (e.g. at age 10 years or age 15 years) was allowed. © 2012 John Wiley & Sons A/S.

  7. A structural equation model to investigate the impact of missing occlusal units on objective masticatory function in patients with shortened dental arches.

    PubMed

    Fueki, K; Yoshida, E; Igarashi, Y

    2011-11-01

    The aim of this study was to investigate the impact of missing occlusal units (MOUs) on objective masticatory function with respect to food comminuting and mixing ability. Sixty partially dentate patients (mean age, 64·1 years) with shortened dental arches participated in the study. Food comminuting ability was assessed using a masticatory performance test with peanuts as a test food. Food mixing ability was assessed using a mixing ability test with a two-coloured wax cube. Maximum bite force (MBF) was measured using a pressure-sensitive film as a mediator for food comminuting and mixing ability. A structural equation model was constructed based on a hypothesis that MOUs would be associated with reduced MBF and impairment of food comminuting and mixing ability. Structural equation modelling analysis found significant direct effects of MOU on median particle size and mixing ability index (MAI) (P < 0·001). In addition, MOU had significant indirect effects on median particle size and MAI with MBF as a mediator (P < 0·05). These results suggest that decrease in occlusal platform area and reduced MBF because of MOUs are associated with the impairment of food comminution and mixing in patients with shortened dental arches.

  8. Influence of scanning and reconstruction parameters on quality of three-dimensional surface models of the dental arches from cone beam computed tomography

    PubMed Central

    Couto Souza, Paulo; Jacobs, Reinhilde; de Azambuja Berti, Soraya; van der Stelt, Paul

    2009-01-01

    The study aim is to investigate the influence of scan field, mouth opening, voxel size, and segmentation threshold selections on the quality of the three-dimensional (3D) surface models of the dental arches from cone beam computed tomography (CBCT). 3D models of 25 patients scanned with one image intensifier CBCT system (NewTom 3G, QR SLR, Verona, Italy) using three field sizes in open- and closed-mouth positions were created at different voxel size resolutions. Two observers assessed the quality of the models independently on a five-point scale using specified criteria. The results indicate that large-field selection reduced the visibility of the teeth and the interproximal space. Also, large voxel size reduced the visibility of the occlusal surfaces and bone in the anterior region in both maxilla and mandible. Segmentation threshold was more variable in the maxilla than in the mandible. Closed-mouth scan complicated separating the jaws and reduced teeth surfaces visibility. The preliminary results from this image-intensifier system indicate that the use of medium or small scan fields in an open-mouth position with a small voxel is recommended to optimize quality of the 3D surface model reconstructions of the dental arches from CBCT. More research is needed to validate the results with other flat-panel detector-based CBCT systems. PMID:19506922

  9. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique

    PubMed Central

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan

    2014-01-01

    Objective This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Methods Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP technique with an oral scanner. Six linear measurements were evaluated in terms of x, y, and z-axes using a non-contact white light scanner. Accuracy was assessed using mean differences between two measurements, and precision was examined using four quantitative methods and the Bland-Altman graphical method. Repeatability was evaluated in terms of intra-examiner variability, and reproducibility was assessed in terms of inter-examiner and inter-method variability. Results The mean difference between plaster models and PUT models ranged from 0.07 mm to 0.33 mm. Relative measurement errors ranged from 2.2% to 7.6% and intraclass correlation coefficients ranged from 0.93 to 0.96, when comparing plaster models and PUT models. The Bland-Altman plot showed good agreement. Conclusions The accuracy and precision of PUT dental models for evaluating the performance of oral scanner and subtractive RP technology was acceptable. Because of the recent improvements in block material and computerized numeric control milling machines, the subtractive RP method may be a good choice for dental arch models. PMID:24696823

  10. [Microcirculation in supporting tissues in patients with unilateral terminal defect of dental arch].

    PubMed

    Gvetadze, R Sh; Krechina, E K; Smirnov, D V; Shamkhalov, D I

    2011-01-01

    By the method laser Doppler fluometry microcirculation in a mucosa of an alveolar process at orthopedic treatment of patients with unilateral trailer defect of a dentition with application of the prosthetic design leaning on dental implants with the help unklammer of bracing. Taped dynamics of change of indicators testified to compensatory changes in regulation of a fabric blood flow in reply to a rendered load. Studying of microhemodynamic processes in tissues of a prosthetic bed, according to LDF, has shown stimulating influence of rational orthopedic treatment on a microcirculation condition.

  11. Posterior arch C-1 screw technique: a cadaveric comparison study.

    PubMed

    Moisi, Marc; Fisahn, Christian; Tkachenko, Lara; Jeyamohan, Shiveindra; Reintjes, Stephen; Grunert, Peter; Norvell, Daniel C; Tubbs, R Shane; Page, Jeni; Newell, David W; Nora, Peter; Oskouian, Rod J; Chapman, Jens

    2017-03-17

    OBJECTIVE Posterior atlantoaxial stabilization and fusion using C-1 lateral mass screw fixation has become commonly used in the treatment of instability and for reconstructive indications since its introduction by Goel and Laheri in 1994 and modification by Harms in 2001. Placement of such lateral mass screws can be challenging because of the proximity to the spinal cord, vertebral artery, an extensive venous plexus, and the C-2 nerve root, which overlies the designated starting point on the posterior center of the lateral mass. An alternative posterior access point starting on the posterior arch of C-1 could provide a C-2 nerve root-sparing starting point for screw placement, with the potential benefit of greater directional control and simpler trajectory. The authors present a cadaveric study comparing an alternative strategy (i.e., a C-1 screw with a posterior arch starting point) to the conventional strategy (i.e., using the lower lateral mass entry site), specifically assessing the safety of screw placement to preserve the C-2 nerve root. METHODS Five US-trained spine fellows instrumented 17 fresh human cadaveric heads using the Goel/Harms C-1 lateral mass (GHLM) technique on the left and the posterior arch lateral mass (PALM) technique on the right, under fluoroscopic guidance. After screw placement, a CT scan was obtained on each specimen to assess for radiographic screw placement accuracy. Four faculty spine surgeons, blinded to the surgeon who instrumented the cadaver, independently graded the quality of screw placement using a modified Upendra classification. RESULTS Of the 17 specimens, the C-2 nerve root was anatomically impinged in 13 (76.5%) of the specimens. The GHLM technique was graded Type 1 or 2, which is considered "acceptable," in 12 specimens (70.6%), and graded Type 3 or 4 ("unacceptable") in 5 specimens (29.4%). In contrast, the PALM technique had 17 (100%) of 17 graded Type 1 or 2 (p = 0.015). There were no vertebral artery injuries found

  12. Double aortic arch anomalies in Children: A Systematic 20-Year Single Center Study.

    PubMed

    Kaldararova, M; Simkova, I; Varga, I; Tittel, P; Kardos, M; Ondriska, M; Vrsanska, V; Masura, J

    2017-10-01

    Aortic arch anomalies underlie numerous congenital disorders. Effectively diagnosing and treating them requires close understanding of cardiovascular embryology. As our Center serves the entire pediatric population of our country, we performed a comprehensive retrospective analysis of all aortic arch anomalies diagnosed at our Center over the past 20 years. We analyzed 40 children with aortic arch anomalies, distinguishing two defect types: Group 1 displayed ring-forming anomalies, and Group 2 other types of aortic arch anomalies that did not form a vascular ring. We performed detailed morphological analyses using echocardiography, angiography, computed tomography, or magnetic resonance imaging and generated a catalog of all aortic arch anomalies present. Group 1 was represented by 25 patients; 40% with persistent both aortic arches, and 60% with various forms of right aortic arch and an incomplete left aortic arch. Group 2 was represented by 15 patients with complex heart defects. On the basis of our dataset, the incidence of all aortic arch anomalies was 0.033%, and of ring-forming pathologies 0.021%. Although aortic arch anomalies are rare, it is important to diagnose them correctly. It is critical to distinguish ring-forming types. Although in complex defects the aortic arch anomaly represents only an additive diagnosis, its correct definition could be crucial for further management. Cumulatively, this unique, long-term study provides a systematic patient registry and offers critical epidemiological data to aid the study of rare congenital cardiovascular defects. Clin. Anat. 30:929-939, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel--a cadaveric study.

    PubMed

    Li, Zong-Ming; Gabra, Joseph N; Marquardt, Tamara L; Kim, Dong Hee

    2013-04-01

    Carpal tunnel morphology plays an essential role in the etiology and treatment of carpal tunnel syndrome. The purpose of this study was to observe the morphological changes of the carpal tunnel as a result of carpal arch width narrowing. It was hypothesized that carpal arch width narrowing would result in increased height and area of the carpal arch. The carpal arch width of eight cadaveric hands was narrowed by a custom apparatus and cross-sectional ultrasound images were acquired. The carpal arch height and area were quantified as the carpal arch width was narrowed. Correlation and regression analyses were performed for the carpal arch height and area with respect to the carpal arch width. The carpal tunnel became more convex as the carpal arch width was narrowed. The initial carpal arch width, height, and area were 25.7 (SD1.9) mm, 4.1 (SD0.6) mm, and 68.5 (SD14.0) mm(2), respectively. The carpal arch height and area negatively correlated with the carpal arch width, with correlation coefficients of -0.974 (SD0.018) and -0.925 (SD0.034), respectively. Linear regression analyses showed a 1mm narrowing of the carpal arch width resulted in proportional increases of 0.40 (SD0.14) mm in the carpal arch height and 4.0 (SD2.2) mm(2) in the carpal arch area. This study demonstrates that carpal arch width narrowing leads to increased carpal arch height and area, a potential mechanism to reduce the mechanical insult to the median nerve and relieve symptoms associated with carpal tunnel syndrome. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel – a cadaveric study

    PubMed Central

    Li, Zong-Ming; Gabra, Joseph N.; Marquardt, Tamara L.; Kim, Dong Hee

    2013-01-01

    Background Carpal tunnel morphology plays an essential role in the etiology and treatment of carpal tunnel syndrome. The purpose of this study was to observe the morphological changes of the carpal tunnel as a result of carpal arch width narrowing. It was hypothesized carpal arch width narrowing would result in increased height and area of the carpal arch. Methods The carpal arch width of eight cadaveric hands was narrowed by a custom apparatus and cross-sectional ultrasound images were acquired. The carpal arch height and area were quantified as the carpal arch width was narrowed. Correlation and regression analyses were performed for the carpal arch height and area with respect to the carpal arch width. Findings The carpal tunnel became more convex as the carpal arch width was narrowed. The initial carpal arch width, height, and area were 25.7 (SD 1.9) mm, 4.1 (SD 0.6) mm, and 68.5 (SD 14.0) mm2, respectively. The carpal arch height and area negatively correlated with the carpal arch width, with correlation coefficients of −0.974 (SD 0.018) and −0.925 (SD 0.034), respectively. Linear regression analyses showed a 1 mm narrowing of the carpal arch width resulted in proportional increases of 0.40 (SD 0.14) mm in the carpal arch height and 4.0 (SD 2.2) mm2 in the carpal arch area. Interpretation This study demonstrates that carpal arch width narrowing leads to increased carpal arch height and area, a potential mechanism to reduce the mechanical insult to the median nerve and relieve symptoms associated with carpal tunnel syndrome. PMID:23583095

  15. Validity and reliability of a three-dimensional dental cast simulator for arch dimension measurements.

    PubMed

    Nouri, Mahtab; Asefi, Sohrab; Baghban, Alireza Akbarzadeh; Aminian, Amin; Shamsa, Mohammad; Massudi, Reza

    2014-11-01

    The accuracy and reproducibility of measurements in a locally made three dimensional (3D) simulator was assessed and compared with manual caliper measurements. A total of 20 casts were scanned by our laser scanner. Software capabilities included dimensional measurements, transformation and rotation of the cast as a whole, separation and rotation of each tooth and clip far. Two orthodontists measured the intercanine width, intermolar width and canine, molar and arch depth on the casts and in 3D simulator. For calculating the reliability coefficient and comparing random and systematic errors between the two methods, intra-class correlation coefficient of reliability (ICC), Dahlberg and paired t-test were used, respectively. The ICC and Dahlberg's formula were also applied to assess intra-examiner and inter-examiner reliability of measurements on the casts and in the simulator (P < 0.05). Canine and molar depth measurements had low reliability on the casts. Reliability between methods for the remaining three variables was 0.87, 0.98 and 0.98 in the maxilla and 0.92, 0.77 and 0.94 in the mandible, respectively. The method error was between 0.31 and 0.48 mm. The mean intra-observer difference were 0.086 and 0.23 mm in the 3D method and caliper. The inter-observer differences were 0.21 and 0.42 mm, respectively. The maximum average absolute difference between the two methods was <0.5 mm, indicating that the new system is indeed clinically acceptable. The examiner reliability was higher in 3D measurements.

  16. Validity and reliability of a three-dimensional dental cast simulator for arch dimension measurements

    PubMed Central

    Nouri, Mahtab; Asefi, Sohrab; Baghban, Alireza Akbarzadeh; Aminian, Amin; Shamsa, Mohammad; Massudi, Reza

    2014-01-01

    Background: The accuracy and reproducibility of measurements in a locally made three dimensional (3D) simulator was assessed and compared with manual caliper measurements. Materials and Methods: A total of 20 casts were scanned by our laser scanner. Software capabilities included dimensional measurements, transformation and rotation of the cast as a whole, separation and rotation of each tooth and clip far. Two orthodontists measured the intercanine width, intermolar width and canine, molar and arch depth on the casts and in 3D simulator. For calculating the reliability coefficient and comparing random and systematic errors between the two methods, intra-class correlation coefficient of reliability (ICC), Dahlberg and paired t-test were used, respectively. The ICC and Dahlberg's formula were also applied to assess intra-examiner and inter-examiner reliability of measurements on the casts and in the simulator (P < 0.05). Results: Canine and molar depth measurements had low reliability on the casts. Reliability between methods for the remaining three variables was 0.87, 0.98 and 0.98 in the maxilla and 0.92, 0.77 and 0.94 in the mandible, respectively. The method error was between 0.31 and 0.48 mm. The mean intra-observer difference were 0.086 and 0.23 mm in the 3D method and caliper. The inter-observer differences were 0.21 and 0.42 mm, respectively. Conclusion: The maximum average absolute difference between the two methods was <0.5 mm, indicating that the new system is indeed clinically acceptable. The examiner reliability was higher in 3D measurements. PMID:25540660

  17. Comparison of arch form between ethnic Malays and Malaysian Aborigines in Peninsular Malaysia

    PubMed Central

    Xinwei, Eunice Soh; Lim, Sheh Yinn; Jamaludin, Marhazlinda; Mohamed, Nor Himazian; Yusof, Zamros Yuzaidi Mohd; Shoaib, Lily Azura; Nik Hussein, Nik Noriah

    2012-01-01

    Objective To determine and compare the frequency distribution of various arch shapes in ethnic Malays and Malaysian Aborigines in Peninsular Malaysia and to investigate the morphological differences of arch form between these two ethnic groups. Methods We examined 120 ethnic Malay study models (60 maxillary, 60 mandibular) and 129 Malaysian Aboriginal study models (66 maxillary, 63 mandibular). We marked 18 buccal tips and incisor line angles on each model, and digitized them using 2-dimensional coordinate system. Dental arches were classified as square, ovoid, or tapered by printing the scanned images and superimposing Orthoform arch templates on them. Results The most common maxillary arch shape in both ethnic groups was ovoid, as was the most common mandibular arch shape among ethnic Malay females. The rarest arch shape was square. Chi-square tests, indicated that only the distribution of the mandibular arch shape was significantly different between groups (p = 0.040). However, when compared using independent t-tests, there was no difference in the mean value of arch width between groups. Arch shape distribution was not different between genders of either ethnic group, except for the mandibular arch of ethnic Malays. Conclusions Ethnic Malays and Malaysian Aborigines have similar dental arch dimensions and shapes. PMID:23112931

  18. Double arch mirror study. Part 2: Engineering analysis report

    NASA Technical Reports Server (NTRS)

    Iraninejad, B.; Vukobratovich, D.

    1983-01-01

    A method of mounting a cryogenically cooled, lightweight, double arch, class mirror for infrared, astronomical telescopes was developed. A 50 cm, fused silica mirror was modified for use in a new mount configuration. The flexures and the finite element analysis of the mirror stresses are reported.

  19. [Clinical study on endoscope-assisted repair of zygomatic arch fracture].

    PubMed

    Luo, Qi; Xiao, Wenzhi; Chen, Yong; Zhang, Li

    2016-04-01

    A study was conducted to investigate the relevant applied technique and clinical value of endoscope-assisted repair of zygomatic arch fracture. A total of 10 cases of unilateral zygomatic arch fracture and 8 cases ofunilateral zygomatic fracture were included. Reduction and fixation of the zygomatic arch in all cases were performed via asmall face incision by an endoscope. Endoscope-assisted repair allowed exposure of zygomatic arch fracture and ended the anatomy of the reset. Zygomatic arch was stabilized with titanium plates. Symmetric malar was achieved in allcases after operation. Patients did not show difficulty in opening the mouth. No chewing problems or severe complicationswere evident. This method had the advantage of hidden incision, and it did not leave scars on the face. Postoperative CT examination showed excellent reduction of zygomatic arch fracture and good fixed position of titanium plate. Endoscope-assisted repair of zygomatic arch fracture via a small face incision can be an alternative operation for zygomaticarch fracture. Patients are less traumatized. There are fewer complications. A good reduction of fracture is achieved.

  20. Prevalence of snoring and facial profile type, malocclusion class and dental arch morphology among snorer and nonsnorer university population

    PubMed Central

    Al-Madani, Gassan H.; Banabilh, Saeed M.; El-Sakhawy, Medhat M.

    2015-01-01

    Objectives: The objectives of this study were to determine the prevalence of snoring in an adult male university population, and to test the null hypothesis that there is no difference in facial profile shape, malocclusion type, or palatal morphology among snorer and nonsnorer. Materials and Methods: Berlin questionnaire was given to 840 students and employees aged 18–45 years (24 ± 40). Both snorers and nonsnorers were assessed for the facial profile type, malocclusion type, and palatal morphology. Chi-square and Student's t-test were used to compare the difference between the two groups. Results: The prevalence of snoring was 16.28%. The most frequent findings among snorer were straight profiles (52.0%), Class I malocclusion (74.7%), and V palatal shape (16.0%), respectively. The Chi-square test revealed a significant difference in terms of V-shaped palatal morphology (P < 0.05); higher neck circumference (NC) (P < 0.007); upper arch length was significantly shorter (P < 0.038); and the inter- first upper premolar distance was significantly narrower (P < 0.013). Conclusion: The null hypothesis is rejected. Snoring in our university population is associated with V-shape palatal morphology, increased NC and decrease in the upper arch length, and inter- first upper premolar distance. PMID:26955628

  1. The 5-year-olds' Index: determining the optimal format for rating dental arch relationships in unilateral cleft lip and palate.

    PubMed

    Chawla, O; Deacon, S A; Atack, N E; Ireland, A J; Sandy, J R

    2012-12-01

    The aim of this investigation was to determine the optimal format for presenting the 5-year-olds' Index reference models for the assessment of dental arch relationships in unilateral cleft lip and palate (UCLP). The 5-year-olds' Index reference models were presented in four different formats: plaster models, coloured acrylic models, and two digital formats, which included three-dimensional digital models (3D), and black and white photographs. These formats were used to rate 45 plaster models of patients born with UCLP by a total of seven examiners comprising experienced and inexperienced examiners. Scoring was undertaken 1 week apart for each format with the patient models reassigned on each occasion to reduce the effect of memory bias. For intra-examiner agreement, the patient models were scored 3 weeks later under similar conditions by the same examiners. The reliability of using the different formats was determined using the plaster reference models as the 'gold' standard for comparison. Analysis of the results using weighted kappa (k) statistics showed the magnitude of agreement for all the formats of the 5-year-olds' Index were good to very good between examiners. The more experienced examiners were consistently more reliable in their scoring using the different formats. This study clearly demonstrated that 3D digital models of the 5-year-olds' Index could prove to be a promising alternative to physical models of the 5-year-olds' Index.

  2. Computational Study of Growth and Remodeling in the Aortic Arch

    PubMed Central

    Alford, Patrick W.; Taber, Larry A.

    2009-01-01

    Opening angles (OAs) are associated with growth and remodeling in arteries. One curiosity has been the relatively large OAs found in the aortic arch of some animals. Here, we use computational models to explore the reasons behind this phenomenon. The artery is assumed to contain a smooth muscle/collagen phase and an elastin phase. In the models, growth and remodeling of smooth muscle/collagen depends on wall stress and fluid shear stress. Remodeling of elastin, which normally turns over very slowly, is neglected. The results indicate that OAs generally increase with longitudinal curvature (torus model), earlier elastin production during development, and decreased wall stiffness. Correlating these results with available experimental data suggests that all of these effects may contribute to the large OAs in the aortic arch. The models also suggest that the slow turnover rate of elastin limits longitudinal growth. These results should promote increased understanding of the causes of residual stress in arteries. PMID:18792831

  3. Double arch mirror study. Part 3: Fabrication and test report

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    A method of mounting a cryogenically cooled, lightweight, double arch, glass mirror was developed for infrared, astronomical telescopes such as the Space Infrared Telescope Facility (SIRTF). A 50 cm, fused silica mirror which was previously fabricated was modified for use with a new mount configuration. This mount concept was developed. The modification of the mirror, the fabrication of the mirror mount, and the room temperature testing of the mounted mirror are reported. A design for a SIRTF class primary mirror is suggested.

  4. Retrospective, cross-sectional study on immediately loaded implant-supported mandibular fixed complete-arch prostheses fabricated with the passive fit cementation technique.

    PubMed

    Able, Francine Baldin; de Mattias Sartori, Ivete Aparecida; Thomé, Geninho; Moreira Melo, Ana Cláudia

    2017-05-05

    Mandibular fixed complete-arch dental prostheses on dental implants have been benefiting patients for a long time, but problems with passive fitting between the metallic framework of the prostheses and the implants might influence its long-term success. The purpose of this cross-sectional study of immediately loaded mandibular fixed complete-arch dental prostheses was to evaluate the survival and success rates of prostheses, the survival rates of dental implants, the occurrence of complications in the prostheses and implants, participant satisfaction, and the association between cantilever length and prosthesis complications. Data were collected from the participants' records. The exposure variables were participant related (sex and age) and treatment related (number of implants and length of cantilever). The outcome variables were the survival and success of the prostheses and implants, complications, and participant satisfaction. The Fisher or chi-square tests was used for the association between 2 qualitative variables (α=.05). Two hundred ninety consecutive participants (1429 implants) with a mean follow-up time of 4.4 years were included. The survival rate for the prostheses was 98.6 and the success rate was 96.6%. The implant survival rate was 99.6%. Sixty-seven participants experienced a prosthetic complication, the most common being tooth fracture. Only 2.45% (n=35) of the implants were associated with screw loosening. Of the total number of participants, 86.9% were completely satisfied with their treatment. The length of the cantilever (up to 25 mm) was not associated with complications (P>.05). Implant-supported mandibular fixed complete-arch dental prostheses fabricated with a passive fit technique provide successful treatment for patients with edentulism. The success and survival rates of implants and prostheses were high. Only straightforward complications were observed. Cantilever length was not associated with complications. Copyright © 2017

  5. In vivo Study of the Accuracy of Dual-arch Impressions

    PubMed Central

    de Lima, Luciana Martinelli Santayana; Borges, Gilberto Antonio; Junior, Luiz Henrique Burnett; Spohr, Ana Maria

    2014-01-01

    Background: This study evaluated in vivo the accuracy of metal (Smart®) and plastic (Triple Tray®) dual-arch trays used with vinyl polysiloxane (Flexitime®), in the putty/wash viscosity, as well as polyether (Impregum Soft®) in the regular viscosity. Materials and Methods: In one patient, an implant-level transfer was screwed on an implant in the mandibular right first molar, serving as a pattern. Ten impressions were made with each tray and impression material. The impressions were poured with Type IV gypsum. The width and height of the pattern and casts were measured in a profile projector (Nikon). The results were submitted to Student’s t-test for one sample (α = 0.05). Results: For the width distance, the plastic dual-arch trays with vinyl polysiloxane (4.513 mm) and with polyether (4.531 mm) were statistically wider than the pattern (4.489 mm). The metal dual-arch tray with vinyl polysiloxane (4.504 mm) and with polyether (4.500 mm) did not differ statistically from the pattern. For the height distance, only the metal dual-arch tray with polyether (2.253 mm) differed statistically from the pattern (2.310 mm). Conclusion: The metal dual-arch tray with vinyl polysiloxane, in the putty/wash viscosities, reproduced casts with less distortion in comparison with the same technique with the plastic dual-arch tray. The plastic or metal dual-arch trays with polyether reproduced cast with greater distortion. How to cite the article: Santayana de Lima LM, Borges GA, Burnett LH Jr, Spohr AM. In vivo study of the accuracy of dual-arch impressions. J Int Oral Health 2014;6(3):50-5. PMID:25083032

  6. In vivo Study of the Accuracy of Dual-arch Impressions.

    PubMed

    de Lima, Luciana Martinelli Santayana; Borges, Gilberto Antonio; Junior, Luiz Henrique Burnett; Spohr, Ana Maria

    2014-06-01

    This study evaluated in vivo the accuracy of metal (Smart®) and plastic (Triple Tray®) dual-arch trays used with vinyl polysiloxane (Flexitime®), in the putty/wash viscosity, as well as polyether (Impregum Soft®) in the regular viscosity. In one patient, an implant-level transfer was screwed on an implant in the mandibular right first molar, serving as a pattern. Ten impressions were made with each tray and impression material. The impressions were poured with Type IV gypsum. The width and height of the pattern and casts were measured in a profile projector (Nikon). The results were submitted to Student's t-test for one sample (α = 0.05). For the width distance, the plastic dual-arch trays with vinyl polysiloxane (4.513 mm) and with polyether (4.531 mm) were statistically wider than the pattern (4.489 mm). The metal dual-arch tray with vinyl polysiloxane (4.504 mm) and with polyether (4.500 mm) did not differ statistically from the pattern. For the height distance, only the metal dual-arch tray with polyether (2.253 mm) differed statistically from the pattern (2.310 mm). The metal dual-arch tray with vinyl polysiloxane, in the putty/wash viscosities, reproduced casts with less distortion in comparison with the same technique with the plastic dual-arch tray. The plastic or metal dual-arch trays with polyether reproduced cast with greater distortion. How to cite the article: Santayana de Lima LM, Borges GA, Burnett LH Jr, Spohr AM. In vivo study of the accuracy of dual-arch impressions. J Int Oral Health 2014;6(3):50-5.

  7. [Study of dental chromatic space].

    PubMed

    Burlui, V; Bortă, Corina; Vrânceanu, Narcisa; Bortă, B

    2005-01-01

    Dental chromatic space has been the topic for many studies and most of all indicated that dental structures are very versatile from the colour point of view, therefore a proper shade selection is difficult to made. Our study made a comparison between the shades of dental structures of men and women of different ages, the measurements being done in three regions: incisal, middle and cervical. We used a spectrophotometer Spectra-Flash 600 and the PC programme Data-Master version 2.3 for both chromatic determinations and the statistical evaluations. The study proved that there are no major differences between the dental shades of men and women; meanwhile chrome increases with age and from incisal to cervical regions. Also, value increases from incisal to cervical region.

  8. Comparative analysis of 3D data accuracy of single tooth and full dental arch captured by different intraoral and laboratory digital impression systems.

    PubMed

    Ryakhovsky, A N; Kostyukova, V V

    2016-01-01

    The aim of this study was to compare the accuracy of digital impressions taken by different intraoral and laboratory scanners. For this purpose a synthetic jaw model with prepared tooth was scanned using intraoral scanning systems: 3D Progress (MHT S.P.A., IT - MHT Optic Research AG, CH); True Definition (3M ESPE, USA); Trios (3Shape A/S, DNK); CEREC AC Bluecam, CEREC Omnicam (Sirona Dental System GmbH, DE); Planscan (Planmeca, FIN); and laboratory scanning systems: s600 ARTI (Zirkonzahn GmbH, IT); Imetric Iscan D104, CH); D900 (3Shape A/S, DNK); Zfx Evolution (Zfx GmbH, DE) (each n=10). Reference-scanning was done by ATOS Core (GOM mbH, DE). The resulting digital impressions were superimposed with the master-scan. The measured deviations by points (trueness) for intraoral scanners were: True Definition - 15.0±2.85 μm (single tooth) and 45.0±19.11 µm (full arch); Trios - 17.1±1.44 and 58.8±27.36 µm; CEREC AC Bluecam - 22.3±5.58 and 20.3±4.13 µm; CEREC Omnicam - 25.0±1.06 and 78.5±27.03 µm; 3D Progress - 26.4±5.75 and 213.5±47.44 µm; Planscan - 54.6±11.58 and 205.2±21.73 µm. For laboratory scanners: Imetric Iscan D104 - 10.2±0.87 μm (stamp) and 65.3±5.36 µm (full arch); Zfx Evolution - 12.8±0.83 and 66.4±2.80 µm; Zirkonzahn s600 ARTI - 15.1±1.36 and 65.9±1.33 µm; 3Shape D900 - 19.9±0.53 and 63.6±0.83 µm. Precision was: True Definition - 19.9±2.77 μm (single tooth) and 40.1±11.04 µm (full arch); Trios - 25.8±2.49 and 69.9±18.95 µm; CEREC AC Bluecam - 36.4±2.78 and 46.6±3.44 µm; CEREC Omnicam - 37.6±3.29 and 76.2±13.36 µm; 3D Progress - 76.9±11.04 and 102.2±8.06 µm; Planscan - 74.3±6.58 and 93.9±15.32 µm. For laboratory scanners: Imetric Iscan D104 - 11.7±4.39 μm (stamp) and 31.2±5.58 µm (full arch); Zfx Evolution - 8.4±0.49 and 24.8±3.98 µm; Zirkonzahn s600 ARTI - 13.4±6.74 and 20.7±4.34 µm; 3Shape D900 - 10.4±0.93 and 17.8±0.62 µm. Whole deviation of the dental arch was: 3D Progress - 98.0±5.70 µm

  9. Comparative study of dental caries and dental fluorosis in populations of different dental fluorosis prevalence.

    PubMed

    Kukleva, Maria P; Kondeva, Veselina K; Isheva, Alexandra V; Rimalovska, Sevda I

    2009-01-01

    There is evidence that the prevalence of dental fluorosis in many countries has increased over the last three decades along with a noted decrease of dental caries. To date no comparative studies of dental caries and dental fluorosis have been conducted in Bulgaria reflecting the present-day conditions of life. To study comparatively the prevalence of dental fluorosis and dental caries and to establish what relationship, if any, there is between them. We performed a comparative analysis of three epidemiological studies carried out in Plovdiv and Dimitrovgrad in 2004, 2005 and 2008. The hypothesis tested was that dental caries was less frequent in populations with higher prevalence of dental fluorosis (with predominance of mild fluorosis cases). Dental fluorosis was diagnosed using Dean's criteria, and dental caries was scored using the WHO criteria. The results were analysed using the alternative analysis and analysis of variance at a level of significance P < 0.05. The prevalence of dental fluorosis in the studied populations in Dimitrovgrad in 2004 was 56.99%, in Plovdiv in 2005--7.80%, and in 2008--23.18%. The comparison of the studies in Dimitrovgrad and Plovdiv in 2005 showed lower prevalence of dental caries and lower DMFT values in all age groups (P < 0.001) in Dimitrovgrad, where the prevalence of dental fluorosis was greater than that in Plovdiv (P < 0.001). The comparison between the studies in Plovdiv alone in 2005 and 2008 showed an increase in dental fluorosis in 2008 (P < 0.001). The prevalence of dental caries was higher in almost all groups, but the differences failed to reach statistical significance (P < 0.001). The DMFT index was higher in 2008 (P < 0.001) with the exception of some age groups. The higher prevalence of dental fluorosis does not necessarily lead to low prevalence of dental caries and low DMFT values in the specific population.

  10. A mathematic-geometric model to calculate variation in mandibular arch form.

    PubMed

    Mutinelli, S; Manfredi, M; Cozzani, M

    2000-04-01

    A mathematic-geometric model was used to evaluate the variation of mandibular dental arch length with respect to the incisor inclination, but without modifying the intercanine width. In analytical terms, the equations of the curves representing the lower dental arch, before and after incisor inclination of 1 mm and of 1 degree, with controlled and uncontrolled tipping, were studied. The length of the mandibular dental arch changed in the parabolic arch form by 1.51 mm for each millimetre of incisor inclination with respect to the occlusal functional plane, by 0.54 mm for each degree of controlled tipping and by 0.43 mm for each degree of uncontrolled tipping. In the elliptical arch form (e = 0.78), it changed by 1.21, 0.43, and 0.34 mm, respectively, in the hyperbolic form by 1.61, 0.57, and 0.46 mm, in the circular form by 1.21, 0.43, and 0.34 mm, and in the catenary form by 2.07, 0.74, and 0.59 mm. The results show that by changing the arch form without modifying the dimension of the dental arch, different arch lengths can be gained for each millimetre of proclination. In addition, by controlled tipping an inter-incisive arch one-fifth longer than by uncontrolled tipping can be obtained. It would be advisable in orthodontic treatment planning to evaluate the type of dental arch, since the space available or the space required changes depending on the arch form and on the orthodontic tooth movement.

  11. Ketoprofen Dental Pain Study.

    PubMed

    Levin, L M; Cooper, S A; Betts, N J; Wedell, D; Hermann, D G; Lamp, C; Secreto, S A; Hersh, E V

    1997-01-01

    Ketoprofen is a nonsteroidal antiinflammatory drug, recently approved as an over-the-counter (OTC) analgesic at a 12.5 mg dosage strength. This is the first published study which explores the analgesic efficacy and safety of ketoprofen 12.5 mg in patients experiencing pain following the removal of impacted third molars. This study was single-dose, double-blind and randomized utilizing a 6-hour in-patient evaluation period. Patients ingested a single dose of ketoprofen 12.5 mg (n = 30), ketoprofen 37.5 mg (n = 32) or placebo (n = 15) when their post-surgical pain reached at least a moderate intensity on a 5-point categorical (CAT) scale and greater than 50 mm on a 100 mm visual analog scale (VAS). Measures of pain intensity and relief were gathered every 20 minutes for the first 2 hours, and then hourly from hours 3 through 6. Adverse drug reactions were also recorded as they occurred. Both dosages of ketoprofen were significantly more efficacious than placebo (two way ANOVAs, p < 0.05). For pain intensity difference (PID) and pain relief, the 12.5 mg dose exhibited statistical superiority from hours 1 through 3, while the 37.5 mg dose exhibited statistical superiority from 40 minutes through 4 hours. Ketoprofen 37.5 mg was significantly more efficacious than the 12.5 mg dose only at 40 minutes for PID(VAS) and relief, and at 60 minutes for PID(VAS). Both ketoprofen dosages displayed significantly greater 3-hr, 4-hr and 6-hr summary analgesic measures (SPID(VAS), SPID(CAT), TOTPAR) than placebo, with the exception of the 6-hr SPID(CAT) measure for ketoprofen 12.5 mg. No serious side effects were observed in this study. We conclude that ketoprofen in a dose range of 12.5 mg to 37.5 mg is a safe and effective analgesic for the relief of post-operative dental pain.

  12. A laboratory study of arched magnetic flux rope eruptions*

    NASA Astrophysics Data System (ADS)

    Tripathi, S.; Gekelman, W. N.

    2010-12-01

    Arched magnetic flux ropes (AMFRs) are arch-shaped twisted magnetic-structures that confine plasma and carry electrical current. Coronal loops and solar prominences are the main examples of AMFRs in the solar atmosphere. Solar AMFRs appear stable for long duration (several Alfven transit times) and then suddenly erupt due to occurrence of instabilities (e.g., kink instability). Solar AMFR eruptions have been frequently observed to evolve into more energetic events such as solar flares and coronal mass ejections. A laboratory plasma experiment has been constructed to simulate such eruptions in an ambient magnetized plasma. The laboratory AMFR (n ~ 1019 m-3 , Te ~ 10 eV, B ~ 1 kG, L ~ 0.5 m) is produced using an annular LaB6 cathode and an annular anode mounted on two movable shafts in a vacuum chamber (1.0 m diameter, 4.5 m long). Each AMFR electrode has an electromagnet to produce a vacuum magnetic field along the curved axis of the AMFR. The vacuum chamber has an additional plasma source and electromagnets to produce the ambient magnetized plasma (n ~ 1018 m-3, Te ~ 4 eV, B ~ 25 G). Two laser beams (1064 nm, ~0.5 J/pulse) strike movable carbon targets placed behind the orifices of the electrodes to generate controlled plasma flows from the AMFR footpoints that drives the eruption. The experiment operates with a 0.5 Hz repetition rate and is highly reproducible. Thus, time evolution of the AMFR is recorded in three-dimensions with high spatio-temporal resolutions using movable diagnostic probes. Initial results on the dramatic eruption of an arched magnetic flux rope will be presented that demonstrate outward expansion of the AMFR, release of the AMFR plasma to the background, and excitation of magnetosonic waves in the ambient plasma. Reference: S. K. P. Tripathi and W. Gekelman, Phys. Rev. Lett. 105, 075005 *Work supported by US DOE and NSF Fast camera image of a laboratory AMFR. Laser generated flows can be seen emanating from the both footpoints of the AMFR.

  13. Double arch mirror study. Part 1: Preliminary engineering report

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    In the proposed design, the NASA AMES 20-in double arch mirror is supported by three clamp and flexure assemblies. The mirror clamp consists of a T-shaped Invar-36 member that goes into a similarly shaped socket in the back of the mirror. The mirror socket is made oversize and contacts the clamp only along the conical surface. The clamp is preloaded by a spring washer and pulls the mirror into contact with the flexure. The clamp is then inserted into the mirror socket through a cutout, is rotated 90 deg, and is then pinned in place. Loading conditions considered in socket design are discussed as well as stress in the socket and clamp. Flexure geometry and stress are examined as well as the effects of flexure error and of mirror cell error.

  14. Intraoral gothic arch tracing.

    PubMed

    Rubel, Barry; Hill, Edward E

    2011-01-01

    In order to create optimum esthetics, function and phonetics in complete denture fabrication, it is necessary to record accurate maxillo-mandibular determinants of occlusion. This requires clinical skill to establish an accurate, verifiable and reproducible vertical dimension of occlusion (VDO) and centric relation (CR). Correct vertical relation depends upon a consideration of several factors, including muscle tone, inter-dental arch space and parallelism of the ridges. Any errors made while taking maxillo-mandibular jaw relation records will result in dentures that are uncomfortable and, possibly, unwearable. The application of a tracing mechanism such as the Gothic arch tracer (a central bearing device) is a demonstrable method of determining centric relation. Intraoral Gothic arch tracers provide the advantage of capturing VDO and CR in an easy-to-use technique for practitioners. Intraoral tracing (Gothic arch tracing) is a preferred method of obtaining consistent positions of the mandible in motion (retrusive, protrusive and lateral) at a comfortable VDO.

  15. Evaluation of accuracy of complete-arch multiple-unit abutment-level dental implant impressions using different impression and splinting materials.

    PubMed

    Buzayan, Muaiyed; Baig, Mirza Rustum; Yunus, Norsiah

    2013-01-01

    This in vitro study evaluated the accuracy of multiple-unit dental implant casts obtained from splinted or nonsplinted direct impression techniques using various splinting materials by comparing the casts to the reference models. The effect of two different impression materials on the accuracy of the implant casts was also evaluated for abutment-level impressions. A reference model with six internal-connection implant replicas placed in the completely edentulous mandibular arch and connected to multi-base abutments was fabricated from heat-curing acrylic resin. Forty impressions of the reference model were made, 20 each with polyether (PE) and polyvinylsiloxane (PVS) impression materials using the open tray technique. The PE and PVS groups were further subdivided into four subgroups of five each on the bases of splinting type: no splinting, bite registration PE, bite registration addition silicone, or autopolymerizing acrylic resin. The positional accuracy of the implant replica heads was measured on the poured casts using a coordinate measuring machine to assess linear differences in interimplant distances in all three axes. The collected data (linear and three-dimensional [3D] displacement values) were compared with the measurements calculated on the reference resin model and analyzed with nonparametric tests (Kruskal-Wallis and Mann-Whitney). No significant differences were found between the various splinting groups for both PE and PVS impression materials in terms of linear and 3D distortions. However, small but significant differences were found between the two impression materials (PVS, 91 μm; PE, 103 μm) in terms of 3D discrepancies, irrespective of the splinting technique employed. Casts obtained from both impression materials exhibited differences from the reference model. The impression material influenced impression inaccuracy more than the splinting material for multiple-unit abutment-level impressions.

  16. Transversal dental arch dimensions in 9-year-old children born in the 1960s and the 1980s.

    PubMed

    Lindsten, R; Ogaard, B; Larsson, E

    2001-12-01

    The transversal arch dimension has been studied in 2 different cohorts of 9-year-old children, a group of 119 (56 girls and 63 boys) from Norway and a group of 133 (72 girls and 61 boys) from Sweden. Half of the children in each group were born in the 1960s and half in the 1980s. The maxillary and mandibular transversal dimensions did not differ between the 1960s groups and the 1980s groups when the maxilla and the mandible were studied separately. When the intermaxillary relationship was assessed, a significant reduction in the intermaxillary difference was found in the boys born in the 1980s compared with the boys born in the 1960s. This was confirmed with different measurement points. In the girls, the mesial drift of the first permanent molars, because of a greater prevalence of caries in the 1960s groups, masked this effect. When the mesial drift of the first permanent molars in the girls born in the 1960s was considered, the transversal intermaxillary difference showed the same secular pattern as in the boys. When the mesial drift of the first permanent molars was considered, the intermaxillary difference in the 1960s groups resembled that found in an American sample of northwest European ancestry born in the 1940s to a greater extent compared with the children born in the 1980s.

  17. Mandibular canine intrusion with the segmented arch technique: A finite element method study.

    PubMed

    Caballero, Giselle Milagros; Carvalho Filho, Osvaldo Abadia de; Hargreaves, Bernardo Oliveira; Brito, Hélio Henrique de Araújo; Magalhães Júnior, Pedro Américo Almeida; Oliveira, Dauro Douglas

    2015-06-01

    Mandibular canines are anatomically extruded in approximately half of the patients with a deepbite. Although simultaneous orthodontic intrusion of the 6 mandibular anterior teeth is not recommended, a few studies have evaluated individual canine intrusion. Our objectives were to use the finite element method to simulate the segmented intrusion of mandibular canines with a cantilever and to evaluate the effects of different compensatory buccolingual activations. A finite element study of the right quadrant of the mandibular dental arch together with periodontal structures was modeled using SolidWorks software (Dassault Systèmes Americas, Waltham, Mass). After all bony, dental, and periodontal ligament structures from the second molar to the canine were graphically represented, brackets and molar tubes were modeled. Subsequently, a 0.021 × 0.025-in base wire was modeled with stainless steel properties and inserted into the brackets and tubes of the 4 posterior teeth to simulate an anchorage unit. Finally, a 0.017 × 0.025-in cantilever was modeled with titanium-molybdenum alloy properties and inserted into the first molar auxiliary tube. Discretization and boundary conditions of all anatomic structures tested were determined with HyperMesh software (Altair Engineering, Milwaukee, Wis), and compensatory toe-ins of 0°, 4°, 6°, and 8° were simulated with Abaqus software (Dassault Systèmes Americas). The 6° toe-in produced pure intrusion of the canine. The highest amounts of periodontal ligament stress in the anchor segment were observed around the first molar roots. This tooth showed a slight tendency for extrusion and distal crown tipping. Moreover, the different compensatory toe-ins tested did not significantly affect the other posterior teeth. The segmented mechanics simulated in this study may achieve pure mandibular canine intrusion when an adequate amount of compensatory toe-in (6°) is incorporated into the cantilever to prevent buccal and lingual crown

  18. Epidemiological study of dental caries.

    PubMed

    Venugopal, T; Kulkarni, V S; Nerurker, R A; Damle, S G; Patnekar, P N

    1998-01-01

    A total of 2000 children (1-14 year age group) attending pediatric OPD, school clinic & well body clinic of Dr. R.N. Cooper Municipal Hospital & K.E.M Hospital, Mumbai were examined for caries prevalence and 35.6% had dental caries. Parental income was not shown to have any bearing on caries prevalence. Parental literacy, particularly maternal literacy was shown to influence caries prevalence in children. The prevalence was low in well-nourished children and in those taking vegetarian type of diet. Frequency of sweet consumption was shown to be associated with prevalence of dental caries. In 1-4 year age group it was noted that bottle fed children were more affected by dental caries. Tooth brush with paste was the commonest method used for cleaning their teeth in all age groups in our study. Caries prevalence was low in those children using tooth brush than in those using tooth powder. Those children who were using neem datun were found to be less affected with dental caries. Dental caries was also found to be low in those who rinsed their mouth with water after food.

  19. Early alveolar bone grafting has a negative effect on maxillary dental arch dimensions of pre-school children with complete unilateral cleft lip and palate.

    PubMed

    Fudalej, P; Janiszewska-Olszowska, J; Wedrychowska-Szulc, B; Katsaros, C

    2011-05-01

    To evaluate maxillary dental arch dimensions in pre-school children with a complete unilateral cleft lip and palate (CUCLP) after early alveolar bone grafting. Intercanine and intermolar widths, length of dental arch and mesiopalatal inclination of both maxillary segments were measured directly on the dental casts of 42 children (27 boys and 15 girls; mean age = 5.2 years, SD 0.5; Early-grafted group), 30 children (18 boys and 12 girls; mean age = 5.8 years, SD 0.8; Non-grafted group), and 40 children (25 boys and 15 girls, mean age = 5.8, SD 0.4; non-cleft Control group). Children from Early-grafted and Non-grafted groups had a CUCLP repaired with a one-stage closure of the entire cleft. An alveolar bone grafting was performed in the Early-grafted group between 2 and 4 years (mean = 2.4, SD 0.6). A one-way anova model with post hoc Tukey's multiple comparison procedures were used to identify intergroup differences. The mesiopalatal inclination of the lesser segment in the Early-grafted group was decreased in comparison with the Non-grafted and Control groups. The intercanine width had a tendency to be reduced in the Early-grafted group relative to Non-grafted group. Early bone grafting results in a larger collapse of the lesser segment than bone grafting carried out between 9 and 12 years of age. © 2011 John Wiley & Sons A/S.

  20. Anatomical Variations in the Branching Pattern of Human Aortic Arch: A Cadaveric Study from Central India

    PubMed Central

    Budhiraja, Virendra; Rastogi, Rakhi; Jain, Vaishali; Bankwar, Vishal; Raghuwanshi, Shiv

    2013-01-01

    Variations of the branches of aortic arch are due to alteration in the development of certain branchial arch arteries during embryonic period. Knowledge of these variations is important during aortic instrumentation, thoracic, and neck surgeries. In the present study we observed these variations in fifty-two cadavers from Indian populations. In thirty-three (63.5%) cadavers, the aortic arch showed classical branching pattern which includes brachiocephalic trunk, left common carotid artery, and left subclavian artery. In nineteen (36.5%) cadavers it showed variations in the branching pattern, which include the two branches, namely, left subclavian artery and a common trunk in 19.2% cases, four branches, namely, brachiocephalic trunk, left common carotid artery, left vertebral artery, and left subclavian artery in 15.3% cases, and the three branches, namely, common trunk, left vertebral artery, and left subclavian artery in 1.9% cases. PMID:25938106

  1. Clinical investigation on axial versus tilted implants for immediate fixed rehabilitation of edentulous arches: preliminary results of a single cohort study.

    PubMed

    Agnini, Alessandro; Agnini, Andrea Mastrorosa; Romeo, Davide; Chiesi, Manuele; Pariente, Leon; Stappert, Christian F J

    2014-08-01

    The purpose of this clinical investigation was to evaluate full-arch fixed-dental restorations supported by immediate loaded axial and tilted implants in a single-cohort study. Survival rate of axial and tilted implants was compared. From 2006 to 2010, 30 patients were recruited and treated with dental implants. Provisional fixed-dental prostheses were screw-retained over axial or axial and tilted implants within 24 hours after surgery. Follow-ups at 6, 12, and 24 months and annually up to 5 years were scheduled, and radiographic evaluation of peri-implant bone level changes was conducted. Thirty patients (20 females and 10 males) were followed up for an average of 44 months (range 18-67 months). Six patients received both upper and lower implant rehabilitations, resulting in 36 restorations. A total of two hundred two implants were placed (maxilla = 118; mandible = 84) and 46% of the fixtures were evaluated at the 4-year recall. Four axial implants were lost in three patients, leading to 98.02% implant (97.56% axial implants and 100% tilted implants) and 100% prosthetic cumulative survival rate, respectively. No significant difference in marginal bone loss was found between tilted and axial implants in both jaws at 1-year evaluation. Midterm results confirmed that immediate loading of axial and tilted implants provides a viable treatment modality for the rehabilitation of edentulous arches. © 2012 Wiley Periodicals, Inc.

  2. Safety and Efficacy of an Aortic Arch Stent Graft with Window-Shaped Fenestration for Supra-Aortic Arch Vessels: an Experimental Study in Swine

    PubMed Central

    Park, Jong Ha; Choe, Jeong Cheon; Kim, Sang-Pil; Park, Tae Sik; Ahn, Jinhee; Park, Jin Sup; Lee, Hye Won; Oh, Jun-Hyok; Choi, Jung Hyun; Cha, Kwang Soo

    2017-01-01

    Background and Objectives Thoracic endovascular aortic repair exhibits limitations in cases where the aortic pathology involves the aortic arch. We had already developed a fenestrated aortic stent graft (FASG) with a preloaded catheter for aortic pathology involving the aortic arch. FASG was suitable for elective cases. Materials and Methods An aortic arch stent graft with a window-shaped fenestration (FASG-W) for supra-aortic arch vessels is suitable for emergent cases. This study aims to test a FASG-W for supra-aortic arch vessels and to perform a preclinical study in swine to evaluate the safety and efficacy of this device. Six FASG-Ws with 1 preloaded catheter were advanced through the iliac artery in 6 swine. The presence of endoleak and the patency and deformity of the grafts were examined with computed tomography (CT) at 4 weeks postoperatively. A postmortem examination was performed at 8 weeks. The mean procedure time for FASG-W was 27.15±4.02 minutes. The mean time for the selection of the right carotid artery was 5.72±0.72 minutes. Results Major adverse events were not observed in any of the 6 pigs who survived for 8 weeks. For the FASG-W, no endoleaks, no disconnection, and no occlusion of the stent grafts were observed in the CT findings or the postmortem gross findings. Conclusion The procedure with the FASG-W was able to be performed safely in a relatively short procedure time and involved an easy technique. The FASG-W was found to be safe and convenient for use in this preclinical study of swine. PMID:28382077

  3. Implant-supported prosthesis misalignment related to the dental arch: a 14-year clinical follow-up.

    PubMed

    das Neves, Flávio Domingues; Coró, Vitor; da Silva Neto, João Paulo; de Mattias Sartori, Ivete Aparecida; do Prado, Ricardo Alves

    2012-08-01

    The purpose of this study was to warn the dental community about a possible problem in function with partial implant-supported prostheses used for long periods. The misalignment between natural teeth and the implant-supported prosthesis on teeth 11 and 12, observed in a 14-year clinical follow-up, illustrates the fact. The metal-ceramic crowns were placed in 1995 after a rigorous occlusal adjustment. Evaluations were made at 4, 6, 9, and 14 years, when it was noticed that the restorations were positioned palatally and extruded in comparison with the natural teeth. After 9 years, a greater discrepancy was noticed, with anterior occlusion and esthetic changes. The possible causes have been discussed: occlusal problems, parafunctional habits, and natural movement. The first 2 options were discarded after clinical analysis and diagnosis. Therefore, the natural movement probably deriving from an interaction of mechanical and genetic factors might have been the cause. The implants do not have periodontal ligaments but rather ankylosis, so they do not suffer those movements. This case emphasizes the need to inform patients that implants can last more than 10 years in function, but this is not the case with restorations, which lose function and esthetics and must be replaced.

  4. Periodontal and dental effects of surgically assisted rapid maxillary expansion, assessed by using digital study models

    PubMed Central

    Siqueira, Danilo Furquim; Cardoso, Mauricio de Almeida; Capelozza, Leopoldino; Goldenberg, Dov Charles; Fernandes, Mariana dos Santos

    2015-01-01

    OBJECTIVE: The present study assessed the maxillary dental arch changes produced by surgically assisted rapid maxillary expansion (SARME). METHODS: Dental casts from 18 patients (mean age of 23.3 years) were obtained at treatment onset (T1), three months after SARME (T2) and 6 months after expansion (T3). The casts were scanned in a 3D scanner (D-250, 3Shape, Copenhagen, Denmark). Maxillary dental arch width, dental crown tipping and height were measured and assessed by ANOVA and Tukey's test. RESULTS: Increased transversal widths from T1 and T2 and the maintenance of these values from T2 and T3 were observed. Buccal teeth tipping also showed statistically significant differences, with an increase in all teeth from T1 to T2 and a decrease from T2 to T3. No statistically significant difference was found for dental crown height, except for left first and second molars, although clinically irrelevant. CONCLUSION: SARME proved to be an effective and stable procedure, with minimum periodontal hazards. PMID:26154457

  5. Immediate full-arch rehabilitation of the severely atrophic maxilla supported by zygomatic implants: a prospective clinical study with minimum follow-up of 6 years.

    PubMed

    Agliardi, E L; Romeo, D; Panigatti, S; de Araújo Nobre, M; Maló, P

    2017-06-24

    The aim of this study was to evaluate the outcomes of immediate full-arch prostheses supported by zygomatic implants alone or in combination with standard fixtures after a minimum of 6 years of loading. From October 2008 to April 2010, 15 patients with severely atrophic maxillae were treated using four zygomatic implants or two zygomatic implants in conjunction with two conventional fixtures. All subjects received a fixed screw-retained prosthesis within 3hours of surgery, while the final restoration was delivered after 6 months. Follow-up examinations were scheduled to evaluate zygomatic implant survival, conventional dental implant success, prosthetic success, plaque and bleeding scores, marginal bone loss for conventional dental implants, and patient satisfaction. Forty-two zygomatic fixtures and 18 standard implants were placed. Patients were followed up for a minimum of 79 months (range 79-97 months, average 90.61 months). No implant was lost, leading to implant and prosthetic survival rates of 100%. Bone loss for conventional implants averaged 1.39±0.10mm after 6 years of function, leading to a 100% implant success rate. High levels of patient satisfaction were recorded. These medium-term results indicate that immediate full-arch rehabilitation supported by zygomatic implants could be considered a viable treatment modality for the severely atrophic maxilla. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  6. Validation of the murine aortic arch as a model to study human vascular diseases

    PubMed Central

    Casteleyn, Christophe; Trachet, Bram; Van Loo, Denis; Devos, Daniel G H; Van den Broeck, Wim; Simoens, Paul; Cornillie, Pieter

    2010-01-01

    Although the murine thoracic aorta and its main branches are widely studied to gain more insight into the pathogenesis of human vascular diseases, detailed anatomical data on the murine aorta are sparse. Moreover, comparative studies between mice and men focusing on the topography and geometry of the heart and aorta are lacking. As this hampers the validation of murine vascular models, the branching pattern of the murine thoracic aorta was examined in 30 vascular corrosion casts. On six casts the intrathoracic position of the heart was compared with that of six younger and six older men of whom contrast-enhanced computer tomography images of the thorax were three-dimensionally reconstructed. In addition, the geometry of the human thoracic aorta was compared with that of the mouse by reconstructing micro-computer tomography images of six murine casts. It was found that the right brachiocephalic trunk, left common carotid artery and left subclavian artery branched subsequently from the aortic arch in both mice and men. The geometry of the branches of the murine aortic arch was quite similar to that of men. In both species the initial segment of the aorta, comprising the ascending aorta, aortic arch and cranial/superior part of the descending aorta, was sigmoidally curved on a cranial/superior view. Although some analogy between the intrathoracic position of the murine and human heart was observed, the murine heart manifestly deviated more ventrally. The major conclusion of this study is that, in both mice and men, the ascending and descending aorta do not lie in a single vertical plane (non-planar aortic geometry). This contrasts clearly with most domestic mammals in which a planar aortic pattern is present. As the vascular branching pattern of the aortic arch is also similar in mice and men, the murine model seems valuable to study human vascular diseases. PMID:20345858

  7. Validation of the murine aortic arch as a model to study human vascular diseases.

    PubMed

    Casteleyn, Christophe; Trachet, Bram; Van Loo, Denis; Devos, Daniel G H; Van den Broeck, Wim; Simoens, Paul; Cornillie, Pieter

    2010-05-01

    Although the murine thoracic aorta and its main branches are widely studied to gain more insight into the pathogenesis of human vascular diseases, detailed anatomical data on the murine aorta are sparse. Moreover, comparative studies between mice and men focusing on the topography and geometry of the heart and aorta are lacking. As this hampers the validation of murine vascular models, the branching pattern of the murine thoracic aorta was examined in 30 vascular corrosion casts. On six casts the intrathoracic position of the heart was compared with that of six younger and six older men of whom contrast-enhanced computer tomography images of the thorax were three-dimensionally reconstructed. In addition, the geometry of the human thoracic aorta was compared with that of the mouse by reconstructing micro-computer tomography images of six murine casts. It was found that the right brachiocephalic trunk, left common carotid artery and left subclavian artery branched subsequently from the aortic arch in both mice and men. The geometry of the branches of the murine aortic arch was quite similar to that of men. In both species the initial segment of the aorta, comprising the ascending aorta, aortic arch and cranial/superior part of the descending aorta, was sigmoidally curved on a cranial/superior view. Although some analogy between the intrathoracic position of the murine and human heart was observed, the murine heart manifestly deviated more ventrally. The major conclusion of this study is that, in both mice and men, the ascending and descending aorta do not lie in a single vertical plane (non-planar aortic geometry). This contrasts clearly with most domestic mammals in which a planar aortic pattern is present. As the vascular branching pattern of the aortic arch is also similar in mice and men, the murine model seems valuable to study human vascular diseases.

  8. Digital workflow in full-arch implant rehabilitation with segmented minimally veneered monolithic zirconia fixed dental prostheses: 2-year clinical follow-up.

    PubMed

    Papaspyridakos, Panos; Kang, Kiho; DeFuria, Catherine; Amin, Sarah; Kudara, Yukio; Weber, Hans-Peter

    2017-08-09

    To illustrate a digital workflow in full-arch implant rehabilitation with minimally veneered monolithic zirconia and to report the outcomes including technical complications. Three patients (5 edentulous arches) received full-arch fixed implant rehabilitation with monolithic zirconia and mild facial porcelain veneering involving a digital workflow. The incisal edges and occluding surface areas were milled out of monolithic zirconia to reduce the possibility of chipping. Porcelain veneering was applied on the facial aspect to improve the esthetic result. Outcomes and technical complications are reported after 2 years of clinical and radiographic follow-up. Implant and prosthesis survival rates were 100% after a short-term follow-up of 2 years. Technical complications were encountered in one patient. They did not adversely affect prosthesis survival or patient satisfaction and were easily addressed. A digital workflow for the design and fabrication of full-arch monolithic zirconia implant fixed implant prostheses has benefits, but caution is necessary during CAD planning of the prosthesis to ensure a successful outcome. Long-term clinical studies are needed to corroborate the findings discussed in this report. This article presents an integrated digital workflow that was implemented for the implant-prosthodontic rehabilitation of three edentulous patients with monolithic zirconia prostheses. Monolithic zirconia has been successfully incorporated in implant prosthodontics in an effort to reduce the technical complications associated with bilayered ceramics. This workflow simplifies design and fabrication of the zirconia prostheses. However, caution should be taken during CAD planning of the prosthesis to make sure the zirconia cylinder is sufficiently thick at the interface with the titanium insert. Additionally, when cutback is planned for facial porcelain veneering, the functional occluding cusps and incisal edges should be fabricated in monolithic zirconia to avoid

  9. Haemodynamical stress in mouse aortic arch with atherosclerotic plaques: Preliminary study of plaque progression

    PubMed Central

    Assemat, P.; Siu, K.K.; Armitage, J.A.; Hokke, S.N.; Dart, A.; Chin-Dusting, J.; Hourigan, K.

    2014-01-01

    Atherosclerotic plaques develop at particular sites in the arterial tree, and this regional localisation depends largely on haemodynamic parameters (such as wall shear stress; WSS) as described in the literature. Plaque rupture can result in heart attack or stroke and hence understanding the development and vulnerability of atherosclerotic plaques is critically important. The purpose of this study is to characterise the haemodynamics of blood flow in the mouse aortic arch using numerical modelling. The geometries are digitalised from synchrotron imaging and realistic pulsatile blood flow is considered under rigid wall assumptions. Two cases are considered; arteries with and without plaque. Mice that are fed under fat diet present plaques in the aortic arch whose size is dependent on the number of weeks under the diet. The plaque distribution in the region is however relatively constant through the different samples. This result underlines the influence of the geometry and consequently of the wall shear stresses for plaque formation with plaques growing in region of relative low shear stresses. A discussion of the flow field in real geometry in the presence and absence of plaques is conducted. The presence of plaques was shown to alter the blood flow and hence WSS distribution, with regions of localised high WSS, mainly on the wall of the brachiocephalic artery where luminal narrowing is most pronounced. In addition, arch plaques are shown to induce recirculation in the blood flow, a phenomenon with potential influence on the progression of the plaques. The oscillatory shear index and the relative residence time have been calculated on the geometry with plaques to show the presence of this recirculation in the arch, an approach that may be useful for future studies on plaque progression. PMID:25349678

  10. High arch

    MedlinePlus

    ... condition can make it difficult to fit into shoes. People who have high arches most often need ... Symptoms include: Shortened foot length Difficulty fitting shoes Foot pain with walking, standing, and running (not everyone has this symptom)

  11. [Dental pulp diseases. Ultramicroscopic studies].

    PubMed

    Conversini, A; Eramo, S; Manna, M G; Negri, P

    1998-12-01

    After the description of the anatomic and histologic aspects of the healthy dental pulp, stress is laid on pulpal pathologies and on the use of ultramicroscopic techniques to analyze the cytologic modifications in normal and pathologic dental pulp tissues. The results obtained are presented.

  12. New classification of lingual arch form in normal occlusion using three dimensional virtual models

    PubMed Central

    Park, Kyung Hee; Bayome, Mohamed; Park, Jae Hyun; Lee, Jeong Woo; Baek, Seung-Hak

    2015-01-01

    Objective The purposes of this study were 1) to classify lingual dental arch form types based on the lingual bracket points and 2) to provide a new lingual arch form template based on this classification for clinical application through the analysis of three-dimensional virtual models of normal occlusion sample. Methods Maxillary and mandibular casts of 115 young adults with normal occlusion were scanned in their occluded positions and lingual bracket points were digitized on the virtual models by using Rapidform 2006 software. Sixty-eight cases (dataset 1) were used in K-means cluster analysis to classify arch forms with intercanine, interpremolar and intermolar widths and width/depth ratios as determinants. The best-fit curves of the mean arch forms were generated. The remaining cases (dataset 2) were mapped into the obtained clusters and a multivariate test was performed to assess the differences between the clusters. Results Four-cluster classification demonstrated maximum intercluster distance. Wide, narrow, tapering, and ovoid types were described according to the intercanine and intermolar widths and their best-fit curves were depicted. No significant differences in arch depths existed among the clusters. Strong to moderate correlations were found between maxillary and mandibular arch widths. Conclusions Lingual arch forms have been classified into 4 types based on their anterior and posterior dimensions. A template of the 4 arch forms has been depicted. Three-dimensional analysis of the lingual bracket points provides more accurate identification of arch form and, consequently, archwire selection. PMID:25798413

  13. Blunt traumatic aortic injuries of the ascending aorta and aortic arch: a clinical multicentre study.

    PubMed

    Mosquera, Victor X; Marini, Milagros; Muñiz, Javier; Gulias, Daniel; Asorey-Veiga, Vanesa; Adrio-Nazar, Belen; Herrera, José M; Pradas-Montilla, Gonzalo; Cuenca, José J

    2013-09-01

    To report the clinical and radiological characteristics, management and outcomes of traumatic ascending aorta and aortic arch injuries. Historic cohort multicentre study including 17 major trauma patients with traumatic aortic injury from January 2000 to January 2011. The most common mechanism of blunt trauma was motor-vehicle crash (47%) followed by motorcycle crash (41%). Patients sustaining traumatic ascending aorta or aortic arch injuries presented a high proportion of myocardial contusion (41%); moderate or greater aortic valve regurgitation (12%); haemopericardium (35%); severe head injuries (65%) and spinal cord injury (23%). The 58.8% of the patients presented a high degree aortic injury (types III and IV). Expected in-hospital mortality was over 50% as defined by mean TRISS 59.7 (SD 38.6) and mean ISS 48.2 (SD 21.6) on admission. Observed in-hospital mortality was 53%. The cause of death was directly related to the ATAI in 45% of cases, head and abdominal injuries being the cause of death in the remaining 55% cases. Long-term survival was 46% at 1 year, 39% at 5 years, and 19% at 10 years. Traumatic aortic injuries of the ascending aorta/arch should be considered in any major thoracic trauma patient presenting cardiac tamponade, aortic valve regurgitation and/or myocardial contusion. These aortic injuries are also associated with a high incidence of neurological injuries, which can be just as lethal as the aortic injury, so treatment priorities should be modulated on an individual basis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. A digital approach to photographing and measuring cleft lip and palate dental study casts.

    PubMed

    Goodfellow, Nicky

    2007-06-01

    This paper discusses whether a digital photographic technique can be used to produce a measurably accurate image of a dental cast arch, in order to assist the outcome assessments of cleft lip and palate surgery. It describes the measurement techniques, and discusses the factors affecting reproducibility. The results indicate that measurements which were taken from a digital image, using an on-screen measuring tool, correlated significantly with measurements taken manually from a plaster dental cast arch.

  15. Comparison of arch forms between Turkish and North American

    PubMed Central

    Celebi, Ahmet A.; Keklik, Hakan; Tan, Enes; Ucar, Faruk I.

    2016-01-01

    ABSTRACT Objective: The aim of this study was to clarify the morphological differences in the mandibular arches of Turkish and North American white subjects. Methods: The sample included 132 Turkish (34 Class I, 58 Class II, and 40 Class III) and 160 North American (60 Class I, 50 Class II, and 50 Class III) subjects. The most facial portion of 13 proximal contact areas was digitized from photocopied images of patients' mandibular dental arches. Clinical bracket points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. The subjects were grouped according to arch form types (tapered, ovoid and square) in order to have frequency distribution compared between ethnic groups in each Angle classification. Results: The Turkish group showed significantly lower molar depth and more significant molar width-depth (W/D) ratio in all three Angle classifications. On the other hand, the Turkish group also showed a significantly larger intercanine width in Class III malocclusion and intermolar width in Class II malocclusion. The most frequent arch forms seen were the ovoid arch form in the Turkish group and the tapered form in the white group. Conclusions: Our results demonstrate that when treating Turkish patients, one should expect to use preformed ovoid arch form orthodontic wires in a significant percentage of patients. PMID:27275615

  16. Solar Arches

    NASA Image and Video Library

    2017-09-28

    The magnetic field lines between a pair of active regions formed a beautiful set of swaying arches, seen in this footage captured by NASA’s Solar Dynamics Observatory on April 24-26, 2017. The arches are traced out by charged particles spinning along the magnetic field lines. These arches, which form a connection between regions of opposite magnetic polarity, are visible in exquisite detail in this wavelength of extreme ultraviolet light. Extreme ultraviolet light is typically invisible to our eyes, but is colorized here in gold. Read more: go.nasa.gov/2pGgYZt NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  17. ArchE - An Architecture Design Assistant

    DTIC Science & Technology

    2016-06-30

    X, Module X 3 Author / Presenter, Date if Needed What is ArchE? ArchE is a software architecture design assistant, which: • Takes quality and...functional requirements as input • Elicits key quality attribute information to refine quality requirements • Elicits key architectural information...Derives candidate architectures • Evaluates whether quality requirements are satisfied • Identifies tradeoffs • Suggests alternative architectures ArchE is

  18. Towering Arches

    NASA Image and Video Library

    2016-04-06

    This still image from an animation from NASA GSFC Solar Dynamics Observatory shows arches of magnetic field lines towered over the edge of the Sun as a pair of active regions began to rotate into view Apr. 5-6, 2016.

  19. A study on dental vacuum system losses.

    PubMed

    Moutsoglou, A; Han, Y

    2000-01-01

    An experimental study was conducted to document system head losses for dental vacuum systems. Experiments were performed to estimate pressure losses and pressure loss coefficients for pertinent dental treatment room hoses and fittings in high-volume evacuation systems. Pressure losses for some polyvinyl chloride (PVC) elbows used in dental plumbing systems were also measured and presented. Friction head losses in straight PVC piping are calculated and documented in graphical form. Calculated values for friction losses are found to correlate exceptionally well with measured experimental data.

  20. Atresia of the Aortic Arch in 4-Year-Old Child: A Clinical Case Study

    PubMed Central

    Nigro Stimato, Vittoria; Didier, Dominique; Beghetti, Maurice; Tissot, Cécile

    2015-01-01

    Atresia of the aortic arch is a rare congenital heart defect with a high mortality when associated with other intracardiac defects. Cardiac magnetic resonance (CMR) provides the exact anatomy of the aortic arch and collateral circulation and is useful to diagnose-associated aortic arch anomalies. This report describes the case of a 4-year-old child with atresia of the aortic arch, referred to our institution with the diagnosis of aortic coarctation and bicuspid aortic valve. On clinical exam, the femoral pulses were not palpable and there was a significant differential blood pressure between the upper and lower limbs. The echocardiography showed a severely stenotic bicuspid aortic valve but was limited for the exact description of the aortic arch. CMR showed absence of lumen continuity between the ascending and descending aorta distal to the left subclavian artery, extending over 5 mm, with the presence of a bend in the arch and diverticulum on either side of the zone of discontinuity, suggesting the diagnosis atresia of the aortic arch rather than coarctation or interruption. The patient benefited from a successful surgical commissurotomy of the aortic valve and reconstruction of the aortic arch with a homograft. The post-operative CMR confirmed the good surgical result. This case emphasizes the utility of CMR to provide good anatomical information to establish the exact diagnosis and the operative strategy. PMID:25853109

  1. A Comparative Study of Bio Degradation of Various Orthodontic Arch Wires: An In Vitro Study

    PubMed Central

    Gopikrishnan, S; Melath, Anil; Ajith, V V; Mathews, N Binoy

    2015-01-01

    Background: Orthodontic wires are the corner stones of the science and art of orthodontics and they remain in the patient’s mouth for a prolonged period of 18-24 months. It is but natural to expect that they will undergo some biodegradation when in the oral environment during that period. This study aims to compare the biodegradation characteristics of four different orthodontic wires, stainless steel, nickel titanium (NiTi), titanium molybdenum alloy (TMA), and copper NiTi and to assess whether these biodegradation products, are within acceptable limits. Materials and Methods: This study involved the incubation of four different wires in artificial saliva and analyzing the amount of metal released from them at the end of a 28 days study period. The metals analyzed for where nickel, chromium, copper, cobalt, manganese, iron, molybdenum, and titanium. The artificial saliva was changed on days 7, 14, and 21 to prevent the saturation of metals in the artificial saliva. At the end of 28 days, these four samples of artificial saliva of each wire were mixed together and analyzed for the eight metals using an inductively coupled plasma spectroscope. Results: The results showed only the release of nickel, chromium, and iron from stainless steel wire, nickel from NiTi wire, nickel, and chromium from copper NiTi and none from TMA wire. Conclusion: The metals released from arch wires are of such minute quantities to be of any biologic hazard. The amount of metals released is well within acceptable biocompatible limits. Though this study has analyzed the biodegradation of various orthodontic wires, orthodontic wires are never used alone in mechanotherapy. Orthodontic wires along with multiband appliance system with which it is always used and in combination with accessories like face bows may release more metals. PMID:25709360

  2. [Clinical study of treatment effects on deep overbite: a comparison between Multiloop edgewise arch wire and manufactured artificial NiTi reverse-curve arch].

    PubMed

    Zhang, Hong-jun

    2010-06-01

    To evaluate the effects of multiloop edgewise arch wire(MEAW) and NiTi reverse-curve arch in correcting deep overbite. Twenty cases(12-27 year of age)with deep overbite were treated with MEAW or NiTi reverse-curve arch. Pre-and post-treatment cephalogram were taken and analyzed. SPSS13.0 software package was used for paired t test. Two methods could intrude incisors and extrude molars.Maxilla and mandibular had no apparent changes, but less time was spent in the MEAW group. Two methods could correct deep overbite by the same mechanism, but the MEAW has more effective results.

  3. Deployment of a Smart Structural Health Monitoring System for Long-Span Arch Bridges: A Review and a Case Study

    PubMed Central

    Chen, Zengshun; Zhou, Xiao; Wang, Xu; Dong, Lili; Qian, Yuanhao

    2017-01-01

    Structural health monitoring (SHM) technology for surveillance and evaluation of existing and newly built long-span bridges has been widely developed, and the significance of the technique has been recognized by many administrative authorities. The paper reviews the recent progress of the SHM technology that has been applied to long-span bridges. The deployment of a SHM system is introduced. Subsequently, the data analysis and condition assessment including techniques on modal identification, methods on signal processing, and damage identification were reviewed and summarized. A case study about a SHM system of a long-span arch bridge (the Jiubao bridge in China) was systematically incorporated in each part to advance our understanding of deployment and investigation of a SHM system for long-span arch bridges. The applications of SHM systems of long-span arch bridge were also introduced. From the illustrations, the challenges and future trends for development a SHM system were concluded. PMID:28925943

  4. Deployment of a Smart Structural Health Monitoring System for Long-Span Arch Bridges: A Review and a Case Study.

    PubMed

    Chen, Zengshun; Zhou, Xiao; Wang, Xu; Dong, Lili; Qian, Yuanhao

    2017-09-19

    Structural health monitoring (SHM) technology for surveillance and evaluation of existing and newly built long-span bridges has been widely developed, and the significance of the technique has been recognized by many administrative authorities. The paper reviews the recent progress of the SHM technology that has been applied to long-span bridges. The deployment of a SHM system is introduced. Subsequently, the data analysis and condition assessment including techniques on modal identification, methods on signal processing, and damage identification were reviewed and summarized. A case study about a SHM system of a long-span arch bridge (the Jiubao bridge in China) was systematically incorporated in each part to advance our understanding of deployment and investigation of a SHM system for long-span arch bridges. The applications of SHM systems of long-span arch bridge were also introduced. From the illustrations, the challenges and future trends for development a SHM system were concluded.

  5. Reversal of dental fluorosis: A clinical study

    PubMed Central

    Mehta, Dhaval N.; Shah, Jigna

    2013-01-01

    Aim: This study was conducted to evaluate the clinical reversal of dental fluorosis with various combinations of calcium, vitamin D3, and ascorbic acid, along with changes in levels of certain biochemical parameters concerned with dental fluorosis. The role of fluoride level of drinking water in the etiology of dental fluorosis and the prevalence of dental fluorosis in both dentitions and teeth were also assessed. Materials and Methods: A total number of 50 patients with clinical features of dental fluorosis without trauma and any adverse habits were selected. Of these, in 30 co-operative patients, estimation of water fluoride level and pretreatment and post-treatment serum and urine fluoride levels were done with ion selective electrode method. The selected 30 patients were divided into three groups, that is, group A, group B, and group C, and were given various combinations of medications like calcium with vitamin D3 supplements, ascorbic acid with vitamin D3 supplements, and chlorhexidine mouthwash (placebo) for three months, respectively. These 30 patients were assessed for any change in the clinical grading of dental fluorosis. Results: No change in clinical grading of dental fluorosis was noted. Considerable reduction in serum and urine fluoride levels was noted in both group A and group B patients. Dental fluorosis was noted in permanent teeth more commonly than deciduous teeth, and permanent maxillary central incisors had the highest prevalence rate. Conclusion: This study comprises only 30 patients with three months of follow-up. So, this sample of patients and duration of follow-up period are conclusive to observe changes in biochemical parameters but not sufficient to observe changes in clinical grading. PMID:23633850

  6. A Comparative Evaluation of Accuracy of the Dies Affected by Tray Type, Material Viscosity, and Pouring Sequence of Dual and Single Arch Impressions- An In vitro Study

    PubMed Central

    Kulkarni, Rahul S.; Shah, Rupal J.; Chhajlani, Rahul; Saklecha, Bhuwan; Maru, Kavita

    2017-01-01

    Introduction The clinician’s skill, impression techniques, and materials play a very important role in recording fine details in an impression for accuracy of fixed partial denture prosthesis. Impression of prepared teeth and of the opposing arch can be recorded simultaneously by dual-arch trays, while the full arch metal trays are used for impressions of prepared teeth in one arch. Aim To measure and compare the accuracy of working dies made from impressions with metal and plastic dual arch trays and metal full arch trays, for two viscosities of impression material and by changing the sequence of pour of working and non-working sides. Materials and Methods A balanced design with independent samples was used to study the three variables (tray type, impression material viscosity, and pouring sequence). An impression made by dual arch trays and single arch trays were divided in to three groups (Group A-plastic dual arch tray, Group B-metal dual arch tray, Group C-full arch metal stock tray). Out of these three groups, two groups (Group A and B) were subdivided in to four subgroups each and one group (Group C) was subdivided in to two subgroups. A sample size of 30 was used in each subgroup yielding a total 300 impressions in three groups or ten subgroups. Impressions were made of a machined circular stainless steel die. All three dimensions (Occlusogingival, Mesiodistal, and Buccolingual) of the working dies as well as stainless steel standard die were measured three times, and the mean was used for the three standard sample values to which all working dies means were compared. Statistical analysis used for this study was a 3-factor analysis of variance with hypothesis testing at α =0.05. Results With respect to the selection of impression material viscosity statistically significant differences were found in the dies for the buccolingual and mesiodistal dimensions. Metal dual arch trays were slightly more accurate in the mesiodistal dimension in comparison to the

  7. A Comparative Evaluation of Accuracy of the Dies Affected by Tray Type, Material Viscosity, and Pouring Sequence of Dual and Single Arch Impressions- An In vitro Study.

    PubMed

    Kulkarni, Poonam R; Kulkarni, Rahul S; Shah, Rupal J; Chhajlani, Rahul; Saklecha, Bhuwan; Maru, Kavita

    2017-04-01

    The clinician's skill, impression techniques, and materials play a very important role in recording fine details in an impression for accuracy of fixed partial denture prosthesis. Impression of prepared teeth and of the opposing arch can be recorded simultaneously by dual-arch trays, while the full arch metal trays are used for impressions of prepared teeth in one arch. To measure and compare the accuracy of working dies made from impressions with metal and plastic dual arch trays and metal full arch trays, for two viscosities of impression material and by changing the sequence of pour of working and non-working sides. A balanced design with independent samples was used to study the three variables (tray type, impression material viscosity, and pouring sequence). An impression made by dual arch trays and single arch trays were divided in to three groups (Group A-plastic dual arch tray, Group B-metal dual arch tray, Group C-full arch metal stock tray). Out of these three groups, two groups (Group A and B) were subdivided in to four subgroups each and one group (Group C) was subdivided in to two subgroups. A sample size of 30 was used in each subgroup yielding a total 300 impressions in three groups or ten subgroups. Impressions were made of a machined circular stainless steel die. All three dimensions (Occlusogingival, Mesiodistal, and Buccolingual) of the working dies as well as stainless steel standard die were measured three times, and the mean was used for the three standard sample values to which all working dies means were compared. Statistical analysis used for this study was a 3-factor analysis of variance with hypothesis testing at α =0.05. With respect to the selection of impression material viscosity statistically significant differences were found in the dies for the buccolingual and mesiodistal dimensions. Metal dual arch trays were slightly more accurate in the mesiodistal dimension in comparison to the plastic trays in reference of tray selection and

  8. Organized Arches

    NASA Image and Video Library

    2017-01-17

    Magnetic arcs of plasma that spiraled above two active regions held their shape fairly well over 18 hours (Jan. 11-12, 2017). The charged plasma is being controlled the magnetic field lines of the active regions. The field lines become clearly visible when viewed in this wavelength of extreme ultraviolet light. Often the arches bend and twist more dynamically than the relatively stable ones seen here. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA12327

  9. Tilted Implants for Full-Arch Rehabilitations in Completely Edentulous Maxilla: A Retrospective Study

    PubMed Central

    Cavalli, Nicolò; Barbaro, Bruno; Spasari, Davide; Azzola, Francesco; Ciatti, Alberto; Francetti, Luca

    2012-01-01

    Purpose. The aims of this study were to assess the treatment outcome of immediately loaded full-arch fixed bridges anchored to both tilted and axially placed implants in the edentulous maxilla and to evaluate the incidence of biological and prosthetic complications. Materials and Methods. Thirty-four patients (18 women and 16 men) were included in the study. Each patient received a maxillary full-arch fixed bridge supported by two axial implants and two distal tilted implants. A total of 136 implants were inserted. Loading was applied within 48 hours of surgery and definitive restorations were placed 4 to 6 months later. Patients were scheduled for followup at 6, 12, 18, and 24 months and annually up to 5 years. At each followup plaque level and bleeding scores were assessed and every complication was recorded. Results. The overall follow-up range was 12 to 73 months (mean 38.8 months). No implant failures were recorded to date, leading to a cumulative implant survival rate of 100%. Biological complications were recorded such as alveolar mucositis (11.8% patients), peri-implantitis (5.9% patients), and temporomandibular joint pain (5.9% patients). The most common prosthetic complications were the fracture or detachment of one or multiple acrylic teeth in both the temporary (20.6% patients) and definitive (17.7% patients) prosthesis and the minor acrylic fractures in the temporary (14.7% patients) and definitive (2.9% patients) prosthesis. Hygienic complications occurred in 38.2% patients. No patients' dissatisfactions were recorded. Conclusions. The high cumulative implant survival rate indicates that this technique could be considered a viable treatment option. An effective recall program is important to early intercept and correct prosthetic and biologic complications in order to avoid implant and prosthetic failures. PMID:23133453

  10. Mandibular arch perimeter changes with lip bumper treatment.

    PubMed

    Osborn, W S; Nanda, R S; Currier, G F

    1991-06-01

    The effects of lip bumper treatment on the mandibular arch were observed in 32 patients with late transitional and early permanent dentitions. Dental cast measurements were made for arch perimeter, arch length, and arch width. Cephalometric radiographs were used to determine labial tipping of the incisors and distal movement of the molars. Arch circumference increased in all patients, ranging from 0.7 mm to 8.8 mm, with an average of 4.1 mm. The mean increase in arch length was 1.2 mm and was largely attributed to anterior tipping of the mandibular incisors. Change in arch length was the most predictive variable for the increase in arch circumference. Passive changes in arch width were recorded, with a mean increase of 2.0 mm in the intercanine distance and 2.5 mm in the first premolar distance. Arch width increments contributed to the increase in arch circumference, but the increases in arch width were not found to be predictive of the change in arch circumference. Changes in either arch circumference or arch length were not related to the duration of treatment, age and sex of the patient, or the eruption status of the permanent second molars.

  11. Contact pressure of the coracoacromial arch in shoulders with joint contracture: A cadaveric study.

    PubMed

    Shiota, Yuki; Yamamoto, Nobuyuki; Kawakami, Jun; Nagamoto, Hideaki; Muraki, Takayuki; Kaneko, Kazuo; Itoi, Eiji

    2017-08-21

    There have been many reports describing that the capsular fibrosis of the shoulder joint is the main cause of frozen shoulder, whereas others reported the significance of subacromial impingement as an etiological factor. The purpose of this study was to investigate the contact pressure between the coracoacromial arch and the rotator cuff tendons to clarify the contact phenomenon in shoulders with joint contracture. Fourteen fresh-frozen cadaveric shoulders were used. Specimens were divided into two groups: normal group (8 shoulders, definition: more than 61° of flexion and abduction and more than 21° of external rotation) and joint contracture group (6 shoulders, definition: less than 60° of flexion and abduction and less than 20° of external rotation). Contact pressure and area beneath the coracoacromial arch were measured by a flexible force sensor during flexion, abduction, internal and external rotation in adduction and abduction, extension and horizontal extension motions. The peak contact pressure under the acromion was observed at 90° in flexion and abduction in the normal group, whereas that in the contracture group was observed at 30° in flexion (P = 0.037) and at 30° in abduction (P = 0.041). Contact pressure in the contracture group was significantly higher than that in the normal group at 20° and 30° of abduction (P = 0.043, P = 0.041, respectively). There were no significant differences of contact pressure during other motions. Although no significant differences of contact pressure beneath the coracoacromial ligament were observed, contact area significantly increased in extension and horizontal extension motion. The contact between the acromion and the rotator cuff was observed in lower angles of flexion and abduction in shoulders with contracture than in those without. When treating patients with shoulder contracture, we need to perform rehabilitation taking such an abnormal movement into consideration. Copyright © 2017 The

  12. Inter-arch digital model vs. manual cast measurements: Accuracy and reliability.

    PubMed

    Kiviahde, Heikki; Bukovac, Lea; Jussila, Päivi; Pesonen, Paula; Sipilä, Kirsi; Raustia, Aune; Pirttiniemi, Pertti

    2017-06-28

    The purpose of this study was to evaluate the accuracy and reliability of inter-arch measurements using digital dental models and conventional dental casts. Thirty sets of dental casts with permanent dentition were examined. Manual measurements were done with a digital caliper directly on the dental casts, and digital measurements were made on 3D models by two independent examiners. Intra-class correlation coefficients (ICC), a paired sample t-test or Wilcoxon signed-rank test, and Bland-Altman plots were used to evaluate intra- and inter-examiner error and to determine the accuracy and reliability of the measurements. The ICC values were generally good for manual and excellent for digital measurements. The Bland-Altman plots of all the measurements showed good agreement between the manual and digital methods and excellent inter-examiner agreement using the digital method. Inter-arch occlusal measurements on digital models are accurate and reliable and are superior to manual measurements.

  13. Educational material of dental anatomy applied to study the morphology of permanent teeth.

    PubMed

    Siéssere, Selma; Vitti, Mathias; de Sousa, Luiz Gustavo; Semprini, Marisa; Regalo, Simone Cecílio Hallak

    2004-01-01

    The purpose of this report is to present educational material that would allow the dental student to learn to easily identify the morphologic characteristics of permanent teeth, and how they fit together (occlusion). In order to do this, macro models of permanent teeth with no attrition were carved in wax and later molded with alginate. These molds were filled with plaster, dental stone and/or cold-cured acrylic resin. The large individual dental stone tooth models were mounted on a wax base, thus obtaining maxillary and mandibular arches which were occluded. These dental arches were molded with plaster or dental stone. The authors suggest that these types of macro models allow an excellent visualization of the morphologic characteristics of permanent teeth and occlusion. Dental students are able to carve the permanent dentition in wax with great facility when they can observe macro models.

  14. Effect of rapid maxillary expansion and transpalatal arch treatment associated with deciduous canine extraction on the eruption of palatally displaced canines: A 2-center prospective study.

    PubMed

    Sigler, Lauren M; Baccetti, Tiziano; McNamara, James A

    2011-03-01

    Our aim was to investigate the effect of rapid maxillary expansion and transpalatal arch therapy combined with deciduous canine extraction on the eruption rate of palatally displaced canines (PDCs) in patients in the late mixed dentition in a 2-center prospective study. Seventy subjects were enrolled based on PDCs diagnosed on panoramic radiographs. The treatment group (TG, 40 subjects) underwent RME followed by TPA therapy and extraction of the deciduous canines. The control group (CG, 30 subjects) received no orthodontic treatment. At the start of the trial, panoramic radiographs and dental casts were compared between the TG and the CG with the Mann-Whitney U test (P <0.05). At the second observation (cervical vertebral maturation stage 5 or 6), all subjects were reevaluated, and the eruption of the maxillary permanent canines was assessed. The rates of success in the TG were compared with those in the CG by means of chi-square tests (P <0.05). The association of PDCs with other dental anomalies was reported. No statistically significant difference was found for any measurement at the start of the trial between the 2 groups. The prevalence rates of eruption of the maxillary canines were 80% for the TG and 28% in the CG, a statistically significant difference (chi-square =16.26, P <0.001). The prevalence rate at the start for the pubertal stages of cervical vertebral maturation (63%) was significantly greater in the unsuccessfully treated subjects than in the successfully treated ones (16%). In the CG, all successful subjects had PDCs that overlapped the corresponding deciduous canine or the distal aspect of the lateral incisor. Eruption of PDCs in both groups was associated significantly with an open root apex. Rapid maxillary expansion therapy followed by a transpalatal arch combined with extraction of the deciduous canine is effective in treating patients in the late mixed dentition with PDCs. Pretreatment variables indicating success of treatment on the

  15. Dental caries is associated with dental fear in childhood: findings from a birth cohort study.

    PubMed

    Torriani, D D; Ferro, R L; Bonow, M L M; Santos, I S; Matijasevich, A; Barros, A J; Demarco, F F; Peres, K G

    2014-01-01

    This study aimed to investigate the prevalence of dental fear in preschool children and to estimate its association with maternal and children characteristics. The study was nested in a population-based birth cohort from Pelotas, Brazil, started in 2004. A sample of 1,129 children aged 5 years was dentally examined, and their mothers were interviewed. Dental fear was investigated using a validated instrument through the question ‘Do you think that your child is afraid of going to the dentist?'. The possible answers were (1) ‘no', (2) ‘yes, a little', (3) ‘yes' and (4) ‘yes, a lot'. The outcome was dichotomized as ‘children without dental fear' (answers 1 and 2) and ‘children with dental fear' (answers 3 and 4). Exploratory variables included demographic characteristics, socioeconomic status, maternal oral health status and maternal behaviors. The main explanatory variables were caries and dental pain. Data were analyzed using multivariable Poisson regression. The prevalence of dental fear was 16.8% (95% confidence interval 14.6-19.0). Multivariate analysis showed that the lower the family income at birth and the higher the severity of dental caries, the higher the prevalence of dental fear. Children who never visited the dentist and those who frequently experienced dental pain were positively associated with higher dental fear prevalence. Presence of dental caries and dental pain were associated with dental fear regardless of socioeconomic origin and lack of dental service use in childhood. © 2014 S. Karger AG, Basel.

  16. Five-Year Results of a Randomized Controlled Trial Comparing Patients Rehabilitated with Immediately Loaded Maxillary Cross-Arch Fixed Dental Prosthesis Supported by Four or Six Implants Placed Using Guided Surgery.

    PubMed

    Tallarico, Marco; Meloni, Silvio Mario; Canullo, Luigi; Caneva, Martina; Polizzi, Giovanni

    2016-10-01

    To compare the 5-year clinical and radiological outcomes of patients rehabilitated with four or six implants placed using guided surgery and immediate function concept. Forty patients randomly received four (All-on-4) or six (All-on-6) immediately loaded implants, placed using guided surgery, to support a cross-arch fixed dental prosthesis. Outcome measures were survival rates of implants and prostheses, complications, peri-implant marginal bone loss, and periodontal parameters. No drop-out occurred. Seven implants failed at the 5-year follow-up examination: six in the All-on-6 group (5%) and one in the All-on-4 group (1.25%), with no statistically significant differences (p = .246). No prosthetic failure occurred. Both group experienced some technical and biologic complications with no statistically significant differences between groups (p = .501). All-on-4 treatment concept demonstrated a trend of more complications during the entire follow-up period. A trend of more implant failure was experienced for the All-on-6 treatment concept. Marginal bone loss (MBL) from baseline to the 5-year follow-up was not statistically different between All-on-4 (1.71 ± 0.42 mm) and All-on-6 (1.51 ± 0.36 mm) groups (p = .12). For periodontal parameters, there were no differences between groups (p > .05). Both approaches may represent a predictable treatment option for the rehabilitation of complete edentulous patients in the medium term. Longer randomized controlled studies are needed to confirm these results. © 2015 Wiley Periodicals, Inc.

  17. A Retrospective Study on Immediate Placement of Neoss Implants with Early Loading of Full-Arch Bridges.

    PubMed

    Andersson, Peter; Degasperi, Werner; Verrocchi, Damiano; Sennerby, Lars

    2015-08-01

    Full-arch clearances of compromised teeth and placement of implant-supported prostheses is one solution for the prosthetic rehabilitation of partially dentate patients. To retrospectively evaluate treatment outcomes after full clearance, immediate placement, and early loading of full-arch fixed bridges. Fifty-five patients subjected to full clearance and placement of 284 Neoss implants (Bimodal™ and Proactive™, Neoss Ltd, Harrogate, UK) in 29 edentulous maxillae and 26 mandibles for early loading (1 to 3 days) of a provisional full-arch bridge were retrospectively evaluated after 1 to 6 years of loading. Osstell™ measurements (Osstell AB, Göteborg, Sweden) were taken at placement and after 3 to 9 months when the provisional bridge was replaced with a permanent one. Marginal bone levels were measured in intraoral radiographs. All patients (100%) wore a fixed bridge at the time of finalizing the study. A total of 18 failures (6.3%) were encountered during the follow-up, giving an overall cumulative survival rate of 93.7%. All failures occurred in the maxilla (10.6%), and no implants were lost in the mandible. More Bimodal™ (9.0%) than Proactive™ (4.1%) implants failed. Failing implants showed a significantly lower mean primary stability than successful ones (p = .015). Failed cases showed a significantly lower average ISQ for all implants (p = .015) and a marked decrease to the second registration, while successful cases showed and maintained high ISQs. The average bone loss after 1 year was 0.8 ± 0.5 mm. Full-arch clearance of severely diseased teeth followed by immediate placement of Neoss implants, early loading with provisional full-arch bridges, and subsequent permanent bridges is a possible treatment modality for partially dentate patients. Caution with this approach is recommended for the maxilla, as opposed to the mandible. © 2013 Wiley Periodicals, Inc.

  18. Shape change in the atlas with congenital midline non-union of its posterior arch: a morphometric geometric study.

    PubMed

    Ríos, Luis; Palancar, Carlos; Pastor, Francisco; Llidó, Susana; Sanchís-Gimeno, Juan Alberto; Bastir, Markus

    2017-10-01

    The congenital midline non-union of the posterior arch of the atlas is a developmental variant present at a frequency ranging from 0.7% to 3.9%. Most of the reported cases correspond to incidental findings during routine medical examination. In cases of posterior non-union, hypertrophy of the anterior arch and cortical bone thickening of the posterior arches have been observed and interpreted as adaptive responses of the atlas to increased mechanical stress. We sought to determine if the congenital non-union of the posterior arch results in a change in the shape of the atlas. This study is an analysis of the first cervical vertebrae from osteological collections through morphometric geometric techniques. A total of 21 vertebrae were scanned with a high-resolution three-dimensional scanner (Artec Space Spider, Artec Group, Luxembourg). To capture vertebral shape, 19 landmarks and 100 semilandmarks were placed on the vertebrae. Procrustes superimposition was applied to obtain size and shape data (MorphoJ 1.02; Klingenberg, 2011), which were analyzed through principal component analysis (PCA) and mean shape comparisons. The PCA resulted in two components explaining 22.32% and 18.8% of the total shape variance. The graphic plotting of both components indicates a clear shape difference between the control atlas and the atlas with posterior non-union. This observation was supported by statistically significant differences in mean shape comparisons between both types of vertebra (p<.0001). Changes in shape were observed in the superior and inferior articular facets, the transverse processes, and the neural canal between the control and non-union vertebrae. Non-union of the posterior arch of the atlas is associated with significant changes in the shape of the vertebra. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Study on Optimal Grouting Timing for Controlling Uplift Deformation of a Super High Arch Dam

    NASA Astrophysics Data System (ADS)

    Lin, Peng; Zhu, Xiaoxu; Li, Qingbin; Liu, Hongyuan; Yu, Yongjun

    2016-01-01

    A grouting model is developed for use during the grouting of the complex foundation of a super high arch dam. The purpose as to determine the optimal grouting timing and appropriate grouting pressure involved in controlling the uplift deformation of the dam. The model determines the optimal grouting time as the height of the arch dam increases with the concrete pouring, by checking the tensile stresses in the dam against standard specifications. The appropriate grouting pressures are given on the basis of the actual grouting pressures monitored during the upstream riverbed foundation grouting. An engineering procedure, applying the model, was then proposed and used during foundation grouting under the toe block of the Xiluodu super high-arch dam in south-western China. The quality of the foundation grouting was evaluated against the results from pressurized water permeability tests, acoustic wave velocity tests, elastic modulus tests and panoramic photographing of the rockmass on completion of the foundation grouting. The results indicated that the proposed grouting model can be applied to effectively reduce the uplift deformation and associated cracking risk for super high arch dams, and it can be concluded that the proposed engineering grouting procedure is a valuable tool for improving foundation grouting under the toe blocks of a super high arch dam.

  20. Dental Wear: A Scanning Electron Microscope Study

    PubMed Central

    Levrini, Luca; Di Benedetto, Giulia

    2014-01-01

    Dental wear can be differentiated into different types on the basis of morphological and etiological factors. The present research was carried out on twelve extracted human teeth with dental wear (three teeth showing each type of wear: erosion, attrition, abrasion, and abfraction) studied by scanning electron microscopy (SEM). The study aimed, through analysis of the macro- and micromorphological features of the lesions (considering the enamel, dentin, enamel prisms, dentinal tubules, and pulp), to clarify the different clinical and diagnostic presentations of dental wear and their possible significance. Our results, which confirm current knowledge, provide a complete overview of the distinctive morphology of each lesion type. It is important to identify the type of dental wear lesion in order to recognize the contributing etiological factors and, consequently, identify other more complex, nondental disorders (such as gastroesophageal reflux, eating disorders). It is clear that each type of lesion has a specific morphology and mechanism, and further clinical studies are needed to clarify the etiological processes, particularly those underlying the onset of abfraction. PMID:25548769

  1. Dental wear: a scanning electron microscope study.

    PubMed

    Levrini, Luca; Di Benedetto, Giulia; Raspanti, Mario

    2014-01-01

    Dental wear can be differentiated into different types on the basis of morphological and etiological factors. The present research was carried out on twelve extracted human teeth with dental wear (three teeth showing each type of wear: erosion, attrition, abrasion, and abfraction) studied by scanning electron microscopy (SEM). The study aimed, through analysis of the macro- and micromorphological features of the lesions (considering the enamel, dentin, enamel prisms, dentinal tubules, and pulp), to clarify the different clinical and diagnostic presentations of dental wear and their possible significance. Our results, which confirm current knowledge, provide a complete overview of the distinctive morphology of each lesion type. It is important to identify the type of dental wear lesion in order to recognize the contributing etiological factors and, consequently, identify other more complex, nondental disorders (such as gastroesophageal reflux, eating disorders). It is clear that each type of lesion has a specific morphology and mechanism, and further clinical studies are needed to clarify the etiological processes, particularly those underlying the onset of abfraction.

  2. Calculus detection calibration among dental hygiene faculty members utilizing dental endoscopy: a pilot study.

    PubMed

    Partido, Brian B; Jones, Archie A; English, Dana L; Nguyen, Carol A; Jacks, Mary E

    2015-02-01

    Dental and dental hygiene faculty members often do not provide consistent instruction in the clinical environment, especially in tasks requiring clinical judgment. From previous efforts to calibrate faculty members in calculus detection using typodonts, researchers have suggested using human subjects and emerging technology to improve consistency in clinical instruction. The purpose of this pilot study was to determine if a dental endoscopy-assisted training program would improve intra- and interrater reliability of dental hygiene faculty members in calculus detection. Training included an ODU 11/12 explorer, typodonts, and dental endoscopy. A convenience sample of six participants was recruited from the dental hygiene faculty at a California community college, and a two-group randomized experimental design was utilized. Intra- and interrater reliability was measured before and after calibration training. Pretest and posttest Kappa averages of all participants were compared using repeated measures (split-plot) ANOVA to determine the effectiveness of the calibration training on intra- and interrater reliability. The results showed that both kinds of reliability significantly improved for all participants and the training group improved significantly in interrater reliability from pretest to posttest. Calibration training was beneficial to these dental hygiene faculty members, especially those beginning with less than full agreement. This study suggests that calculus detection calibration training utilizing dental endoscopy can effectively improve interrater reliability of dental and dental hygiene clinical educators. Future studies should include human subjects, involve more participants at multiple locations, and determine whether improved rater reliability can be sustained over time.

  3. [Experimental study of the influence of removal of the zygomatic arch on craniofacial growth and development].

    PubMed

    Umemura, S

    1989-05-01

    To observe effects of the procedure on craniofacial growth and development, the author removed 10mm of the right zygomatic arch from rats. The subjects (128 rats) were divided into 3 groups: operation group, sham-operation group, and control group. Surgical removal of the right side of the zygomatic arch was performed on 51 rats; sham operations were performed on 42 rats, and 35 rats served as controls. Operations were performed 30 days after the animals' births. The rats were sacrificed 60 to 120 days after birth. Lateral and parietal cephalograms of the crania were projected by means of a profile projector, model V-16, and enlarged 5 times. Because they reveal craniofacial-facial morphology most clearly, 15 lateral and 7 parietal points were selected. Coordinates of these points were plotted by means of an X--Y plotter system Tracings were composed as follows: For lateral cephalograms, the intersphenoid synchondrosis(S)was the zero point, and the line between S and the basion (Ba) was the abscissa. For parietal cephalograms, the occipital bone was the zero point; and the line between (0) and the upper central (Ui) was the abscissa. The masseter muscles were microsectioned for observation of changes in muscle fibers. Results 1. There were no significant differences among the body weights of the 3 groups (control, operation, and sham operation). 2. There were no significant differences in ulnar length among the 3 groups 3. Facial asymmetry and changes in occlusion were noted in the group observed 120 days after surgery. 4. Lateral cephalographic examination showed that the zygomatic arch has almost no influence on craniofacial growth and development in terms of relations among the points examined. 5. Parietal cephalographic examination showed that removal of the zygomatic arch promoted depth development and suppressed width development in the zygomatic-arch region of the side on which surgery was performed. This may indicate that the zygomatic arch acts to suppress

  4. Clinical, microbiological, and immunological aspects of healthy versus peri-implantitis tissue in full arch reconstruction patients: a prospective cross-sectional study.

    PubMed

    Ata-Ali, Javier; Flichy-Fernández, Antonio Juan; Alegre-Domingo, Teresa; Ata-Ali, Fadi; Palacio, Jose; Peñarrocha-Diago, Miguel

    2015-04-01

    Due to the world-wide increase in treatments involving implant placement, the incidence of peri-implant disease is increasing. Late implant failure is the result of the inability to maintain osseointegration, whose most important cause is peri-implantitis. The aim of this study was to analyze the clinical, microbiological, and immunological aspects in the peri-implant sulcus fluid (PISF) of patients with healthy dental implants and patients with peri-implantitis. PISF samples were obtained from 24 peri-implantitis sites and 54 healthy peri-implant sites in this prospective cross-sectional study. The clinical parameters recorded were: modified gingival index (mGI), modified plaque index (mPI) and probing pocket depth (PPD). The periodontopathogenic bacteria Tannerella forsythia, Treponema denticola and Porphyromonas gingivalis were evaluated, together with the total bacterial load (TBL). PISF samples were analyzed for the quantification of Interleukin (IL)-8, IL-1β, IL-6, IL-10 and Tumor Necrosis Factor (TNF)-α using flow cytometry (FACS). The mGI and PPD scores in the peri-implantitis group were significantly higher than the healthy group (p < 0.001). A total of 61.5% of the patients with peri-implantitis had both arches rehabilitated, compared with 22.7% of patients with healthy peri-implant tissues; there was no implant with peri-implantitis in cases that received mandibular treatment exclusively (p < 0.05). Concentrations of Porphyromonas gingivalis (p < 0.01), association with bacteria Porphyromonas gingivalis and Treponema denticola (p < 0.05), as well as the TBL (p < 0.05) are significantly higher in the peri-implantitis group. IL-1β (p < 0.01), IL-6 (p < 0.01), IL-10 (p < 0.05) and TNF-α (p < 0.01) are significantly higher at the sites with peri-implantitis compared to healthy peri-implant tissue, while IL-8 did not increase significantly. The results of the present study involving a limited patient sample suggest that the peri-implant microbiota and

  5. Dentoalveolar mandibular changes with self-ligating versus conventional bracket systems: A CBCT and dental cast study

    PubMed Central

    de Almeida, Marcio Rodrigues; Futagami, Cristina; Conti, Ana Cláudia de Castro Ferreira; Oltramari-Navarro, Paula Vanessa Pedron; Navarro, Ricardo de Lima

    2015-01-01

    OBJECTIVE: The aim of the present study was to compare dentoalveolar changes in mandibular arch, regarding transversal measures and buccal bone thickness, in patients undergoing the initial phase of orthodontic treatment with self-ligating or conventional bracket systems. METHODS: A sample of 25 patients requiring orthodontic treatment was assessed based on the bracket type. Group 1 comprised 13 patients bonded with 0.022-in self-ligating brackets (SLB). Group 2 included 12 patients bonded with 0.022-in conventional brackets (CLB). Cone-beam computed tomography (CBCT) scans and a 3D program (Dolphin) assessed changes in transversal width of buccal bone (TWBB) and buccal bone thickness (BBT) before (T1) and 7 months after treatment onset (T2). Measurements on dental casts were performed using a digital caliper. Differences between and within groups were analyzed by Student's t-test; Pearson correlation coefficient was also calculated. RESULTS: Significant mandibular expansion was observed for both groups; however, no significant differences were found between groups. There was significant decrease in mandibular buccal bone thickness and transversal width of buccal bone in both groups. There was no significant correlation between buccal bone thickness and dental arch expansion. CONCLUSIONS: There were no significant differences between self-ligating brackets and conventional brackets systems regarding mandibular arch expansion and changes in buccal bone thickness or transversal width of buccal bone. PMID:26154456

  6. Palatal positioned implants in severely atrophic maxillae versus conventional implants to support fixed full-arch prostheses: Controlled retrospective study with 5 years of follow-up

    PubMed Central

    Candel-Marti, Eugenia; Peñarrocha-Oltra, David; Bagán, Leticia; Peñarrocha-Diago, Maria

    2015-01-01

    Background To evaluate soft tissue conditions and bone loss around palatal positioned implants supporting fixed full-arch prostheses to rehabilitate edentulous maxillae with horizontal atrophy and compare them with conventional well-centered implants placed in non-atrophic maxillae after a minimum follow-up of 5 years. Material and Methods A clinical retrospective study was performed of patients that were rehabilitated with full-arch fixed implant-supported maxillary prostheses and had a minimum follow-up of 5 years after implant loading. Patients were divided into 2 groups: patients with class IV maxilla according to Cawood and Howell and treated with palatal positioned implants (test) and with class III maxilla and treated with implants well-centered in the alveolar ridge and completely surrounded by bone (control). The following variables were assessed: age, sex, frequency of tooth brushing, smoking, type of prosthesis, type of implant, implant success, amount of buccal keratinized mucosa, buccal retraction, probing depth, plaque index, modified bleeding index, presence of mucositis or peri-implantitis and peri-implant bone loss. Statistical analysis was performed applying Chi2 Test and Student’s t-test using alpha set at 0.05. Results A total of 57 patients were included: 32 patients with 161 palatal positioned implants (test) and 25 patients with 132 well centered implants (control). No statistically significant differences were found regarding age, sex and smoking, but test group patients reported a significantly higher frequency of daily tooth brushing. Implant success rates were 96.9% for test group implants and 96.0% for control group implants. Peri-implant mucosa retraction was significantly higher in the control group than in the test group (p=0,017). No significant differences were observed either for all the other assessed clinical parameters or for peri-implant bone loss. Conclusions Despite its limitations the outcomes of the present study suggest

  7. Self Tapping Screws v/s Erich Arch Bar for Inter Maxillary Fixation: A Comparative Clinical Study in the Treatment of Mandibular Fractures.

    PubMed

    Nandini, G D; Balakrishna, Ramdas; Rao, Jyotsna

    2011-06-01

    Numerous methods have been described for achievement of Intermaxillary fixation in the treatment of fractures of facial skeleton. Conventional methods like Erich arch bars and eyelet wires are currently most common methods for achieving intermaxillary fixation (IMF), but they have their own disadvantages. Since 1989, IMF using intraoral self tapping IMF screws has been introduced for treatment of mandibular fractures. The aim of this work was to compare the efficacy, advantages, disadvantages indications and potential complications associated with Erich archbar v/s self tapping IMF screws in the management of mandibular fractures. Twenty patients with mandibular fractures, reporting to Department of Oral and Maxillofacial Surgery, The Oxford Dental College, Bangalore were evaluated, to compare the efficacy of two techniques. The parameters considered were, time taken, perforations in the gloves, patient acceptance, oral hygiene, iatrogenic dental injuries, and needle stick injuries during IMF with Erich arch Bar and self tapping IMF screws. The mean time taken for IMF was 8.52 ± 2.7 min with screws as compared to 100 min with Erich arch bars. Mean number of perforations were significantly more in Group II. Oral hygiene status was good in 90% and fair in 10% of Group I and 100% fair in Group II patients. Use of self tapping IMF screws for intermaxillary fixation is a valid alternative to conventional Erich arch bars in the treatment of mandibular fractures. Iatrogenic injury to dental roots is the most important problem to this procedure, which can be minimized by careful radiographic evaluation and treatment planning.

  8. Function of the triceps surae muscle group in low and high arched feet: an exploratory study.

    PubMed

    Branthwaite, Helen; Pandyan, Anand; Chockalingam, Nachiappan

    2012-06-01

    The Achilles tendon has been shown to be comprised of segmental components of tendon arising from the tricpes surae muscle group. Motion of the foot joints in low and high arched feet may induce a change in behaviour of the triceps surae muscle group due to altered strain on the tendon. Surface electromyogram of the medial and lateral gastrocnemius and the soleus muscle from 12 subjects (with 6 low arched and 6 high arched feet) (1:1) was recorded whilst walking at a self selected speed along a 10m walkway. The results showed a high variability in muscle activity between groups with patterns emerging within groups. Soleus was more active in 50% of the low arch feet at forefoot loading and there was a crescendo of activity towards heel lift in 58% of all subjects. This observed variability between groups and foot types emphasises the need for further work on individual anatomical variation and foot function to help in the understanding and management of Achilles tendon pathologies and triceps surae dysfunction.

  9. Carbon Dioxide in the Aortic Arch: Coronary Effects and Implications in a Swine Study

    SciTech Connect

    Culp, William C. Porter, Thomas R.; Culp, William C.; Vonk, Brian N.

    2003-04-15

    Purpose: CO{sub 2} angiography is considered dangerous in the aortic arch where bubbles may cause critical cerebral and cardiac ischemia. We investigated CO{sub 2}distribution, physiologic effects in the heart, methods of detection and treatments. Methods: Eight pigs had CO{sub 2}and iodinated contrast arch angiograms in supine and both lateral decubitus positions. An electrocardiogram, physiologic data and cardiac ultrasound were obtained. Therapies included precordial thumps and rolls to lateral decubitus positions. Results: Supine high descending aorta CO{sub 2} injections floated retrograde up the arch during diastole and preferentially filled the right coronary artery (RCA): mean score 3.5 (of 4), in nominate artery 2.4, left coronary artery 1.2; n = 17; p = 0.0001. Aortic root injections preferentially filled the RCA when the animal was supine, left coronary in the right decubitus position, and showed a diffuse pattern in the left decubitus position. Right decubitus rolls filled both coronaries causing several lethal arrhythmias. Precordialthumps successfully cleared CO{sub 2}. Ultrasound is a sensitive detector of myocardial CO{sub 2}. Conclusion: Arch distribution of CO{sub 2} primarily involves the RCA. Diagnostic ultrasound detects cardiac CO{sub 2} well. Precordial thumps are an effective treatment.

  10. Brief research on arch hinge of the steel truss arch bridge by contact problem under local stress

    NASA Astrophysics Data System (ADS)

    He, Wei; Zhu, Yinqiao; Chen, Renlong

    2017-06-01

    Because of its wide deck, elegant design and reasonable stress, the steel truss arch bridge is suitable for urban bridges. In the steel truss arch bridge, the main arch hinge is an important structure, the local structure and the stress is complex, and it is necessary to analyze the local stress state of the arch hinge. Arch hinge problem belongs to the contact problem, this paper based on Chengdu Tianfu District Shenyang Lu Xi Duan Jin Jiang in bearing steel truss arch bridge design, take the finite element software ANSYS on the main arch hinge is locally analyzed, the arch at the junction of reliable performance test. Studies have shown that half through steel truss arch bridge should be adopted by reasonable cylindrical arch hinge, and Hertz theory is in the analysis of the arch hinge contact does not apply.

  11. Clinical Variability in Arch Wires: A Preliminary Study Evaluating Mechanical and Surface Characteristics of Two Different Sized Rectangular Stainless Steel Wires

    PubMed Central

    Vena, Alessandro; Carey, Jason; Badawi, Hisham

    2007-01-01

    Experimental characterization of arch wires has been performed in many previous studies; however with the advent of new arch wire materials being introduced, some new experimental methods and characterization are required. Since literature is available for comparison, this paper examines mechanical and physical characteristics of steel arch wires to quantify their variability in engineering terms. Furthermore, the effect of wire size on properties was evaluated using two of the most common wire sizes. Finally, manufacturing consistency was verified by testing samples from different lots. PMID:19662123

  12. A Study to Determine the Dental Needs in Ohio.

    ERIC Educational Resources Information Center

    Ohio Board of Regents, Columbus.

    The objective of this study includes a determination of the need for additional dental service and an examination of the dental service delivery system in the state of Ohio. Recognizing that the question of dental manpower and the service it delivers is but one facet of the area of oral health maintenance, and that manpower needs are affected by…

  13. Gender identification and morphologic classification of tooth, arch and palatal forms in Saudi population

    PubMed Central

    Mohammad, Aljanakh; Koralakunte, Pavankumar Ravi

    2015-01-01

    Aims: To determine various tooth form, arch form, and palatal form with gender identification between males and females of the Saudi population. Materials and Methods: Irreversible hydrocolloid impressions were made of the maxillary teeth of 100 dentate male and female subjects to obtain study casts. A standardized procedure was adopted to photograph the maxillary dental arches and the maxillary central incisors on the study casts taken from each subject. The outline form of tooth, arch, and palatal form were determined using a standardized method. The average of six prosthodontist's evaluation was considered who classified the outline tracings visually. The statistical analysis was performed using Chi-Square and results tabulated. Results: The predominant tooth is combination form in males and ovoid form in females, the predominant arch is ovoid form in males and square form in females and the predominant palatal form are both U and V shaped in males and U-shaped in females. Conclusion: Except for the tooth form there was a significant difference with arch and palatal form among males and females of the population group studied. The determined tooth, arch and palatal forms are useful in selection and arrangement of artificial teeth among Saudi edentulous population group. Generalizing from the study is questionable as the sample size is small. Further studies should be conducted in a larger sample to confirm the study results PMID:26538903

  14. Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA).

    PubMed

    Schwertner, Alessandro; Almeida, Renato Rodrigues de; Gonini, Alcides; Almeida, Marcio Rodrigues de

    2017-02-01

    The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back.

  15. Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA)

    PubMed Central

    Schwertner, Alessandro; de Almeida, Renato Rodrigues; Gonini, Alcides; de Almeida, Marcio Rodrigues

    2017-01-01

    ABSTRACT Objective: The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Methods: Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Results: Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Conclusion: Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back. PMID:28444014

  16. An Infrared Study of the Dust Properties and Geometry of the Arched Filaments H ii Region with SOFIA/FORCAST

    NASA Astrophysics Data System (ADS)

    Hankins, M. J.; Lau, R. M.; Morris, M. R.; Herter, T. L.

    2017-03-01

    Massive stellar clusters provide radiation (˜ {10}7{--}{10}8 {L}⊙ ) and winds (˜1000 km s-1) that act to heat dust and shape their surrounding environment. In this paper, the Arched Filaments in the Galactic center were studied to better understand the influence of the Arches cluster on its nearby interstellar medium (ISM). The Arched Filaments were observed with the Faint Object InfraRed CAMera for the SOFIA Telescope at 19.7, 25.2, 31.5, and 37.1 μm. Color-temperature maps of the region created with the 25.2 and 37.1 μm data reveal relatively uniform dust temperatures (70-100 K) over the extent of the filaments (˜25 pc). Distances between the cluster and the filaments were calculated assuming equilibrium heating of standard-size ISM dust grains (˜0.1 μm). The distances inferred by this method are in conflict with the projected distance between the filaments and the cluster, although this inconsistency can be explained if the characteristic grain size in the filaments is smaller (˜0.01 μm) than typical values. DustEM models of selected locations within the filaments show evidence of depleted abundances of polycyclic aromatic hydrocarbons (PAHs) by factors of ˜1.6-10 by mass compared to the diffuse ISM. The evidence for both PAH depletion and a smaller characteristic grain size points to processing of the ISM within the filaments. We argue that the eroding of dust grains within the filaments is not likely attributable to the radiation or winds from the Arches cluster, but may be related to the physical conditions in the Galactic center.

  17. Wellness Among Dental Students: An Institutional Study.

    PubMed

    Harrison, Peter L; Shaddox, Luciana M; Garvan, Cynthia W; Behar-Horenstein, Linda S

    2016-09-01

    The high prevalence of distress among health professionals during their education has fostered increased interest in the study of student well-being. The aim of this study was to assess the self-perceived wellness of dental students and determine the relationship between factors affecting wellness and demographic variables. An online questionnaire was distributed to 334 first-through fourth-year dental students at one U.S. dental school. The questionnaire consisted of modified versions of the Perceived Wellness Survey, Medical Outcomes Study Social Support Survey, and Mental Health Inventory and also collected demographic information. The response rate was 78% (N=261). More than 80% of the respondents reported that they were happy all, most, or a good bit of the time. These students exhibited a strong sense of self-worth, were positive about their friendships, and perceived they had good social support. Less than 20% of respondents did not view their physical health as excellent and identified a lack of self-perceived wellness. First-year and single students reported statistically less social support. Students who were parents perceived their wellness less favorably. Hispanic and Asian students were less happy regarding their mental health than white and African American students. These findings suggest that students, especially Hispanic and Asian students, may benefit from programs that promote student well-being. Academic programs that encourage students to work together and promote peer-to-peer involvement may be beneficial, especially for first-year and single students.

  18. [Total resection of the zygomatic arch in the growth period: experimental study in rats].

    PubMed

    Procopio, Antônio Sílvio Fontão; Lemos, José Benedito Dias; Rocha, Elza Maria Villanova Fernandes da; Goulart, Alan Cruvinel

    2002-01-01

    The results obtained after total unilateral resection of the zygomatic arch in Wistar rats were evaluated by means of cephalometric measurements. The resection of the right zygomatic arch was carried out in one-month-old rats, and the animals were sacrificed two months later. The skull and hemimandibles were submitted to axial and lateral radiographic incidences. Based on the obtained radiographs, measurements were carried out by means of a computer system, which compared both sides of the specimens. The obtained values were submitted to statistical analysis. There was significant difference as to the extent of the temporal fossa, but there was no significant difference as to other measures of the maxilla. There was significant difference between both sides regarding the height of the body and the length of the base of the mandible.

  19. A retrospective study of traumatic dental injuries.

    PubMed

    Atabek, Didem; Alaçam, Alev; Aydintuğ, Itır; Konakoğlu, Gonca

    2014-04-01

    The prognosis of dental trauma cases varies depending on the time elapsed after the trauma before treatment started. The aim of this study was to examine epidemiological and dental data from traumatic injuries to primary and permanent teeth during the period from 2005 to 2010. The examinations aimed to determine the age and sex distributions of patients, the causes of tooth injury, the type of teeth injured, the monthly distribution of the trauma, the time elapsed between injury and treatment, and the classification of the traumatized teeth and their treatments. The dental trauma records of patients with an average age of 9 years, including 120 girls (35.3%) and 220 boys (64.7%), were evaluated. The most commonly affected teeth were the maxillary central incisors (66.24%). The main cause was falls (70.1%). In primary dentition, subluxation (36.4%) was observed in the highest percentage of injured teeth, and in permanent dentition, the most common observation was uncomplicated crown fractures (44.9%). Only 18 patients (2.9%) were referred to the clinic within 1 h following the injury. The most frequent treatment for primary teeth was examination and follow up (63.9%). Restoration with composite resin (26.3%) and root canal treatment (28.6%) were the most common procedures for permanent teeth. It was revealed that although the most frequent type of injury in permanent dentition was uncomplicated crown fracture, the root canal treatment was the most common treatment in permanent dentition. This finding suggests that when the checkup time after the injury was delayed, the pulp could lose vitality. This finding reveals that it is important to inform the parents about dental trauma and the importance of bringing their children fast to a dentist in trauma cases. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Patient-related and financial outcomes analysis of conventional full-arch rehabilitation versus the All-on-4 concept: a cohort study.

    PubMed

    Babbush, Charles A; Kanawati, Ali; Kotsakis, Georgios A; Hinrichs, James E

    2014-04-01

    Patient-related variables such as cost of treatment, length of the treatment period, and comfort provided by the interim prosthesis when treatment planning for full-arch rehabilitation are often neglected in dental publications. Two patient cohorts were followed up longitudinally in this study: the "All-on-4 treatment concept group" and the "historical group." The number of implants, total treatment time, number of surgical procedures, number of sinus grafts, necessity for immediate provisional implants, adjusted cost associated for treatment in each group, and the quality of interim prosthesis were compared. The total adjusted cost for patients receiving All-on-4 treatment concept averaged at $42,422 ± 3860 (&OV0556;31,392 ± 2856), whereas the mean total adjusted cost for the historical group was $57,944 ± 20,198 (&OV0556;42,879 ± 2113) (P = 0.01). The difference in cost had a mean value of $7307 (&OV0556;5407) per jaw. Factors associated with complexity of treatment and patient comfort, such as the quality of interim prosthesis, number of surgeries, and duration of treatment time, all significantly favored the All-on-4 treatment concept group in comparison with conventional treatment modalities. When implant rehabilitation of the total jaw is sought, the All-on-4 treatment concept should be considered the least costly and least time consuming treatment option.

  1. Choosing indicators of natural resource condition: A case study in Arches National Park, Utah, USA

    USGS Publications Warehouse

    Belnap, J.

    1998-01-01

    Heavy visitor use in many areas of the world have necessitated development of ways to assess visitation impacts. Arches National Park recently completed a Visitor Experience and Resource Protection (VERP) plan. Integral to this plan was developing a method to identify biological indicators that would both measure visitor impacts and response to management actions. The process used in Arches for indicator selection is outlined here as a model applicable to many areas facing similar challenges. The steps were: (1) Vegetation types most used by visitors were identified. Impacted and unimpacted areas in these types were sampled, comparing vegetation and soil factors. (2) Variables found to differ significantly between compared sites were used as potential indicators. (3) Site-specific criteria for indicators were developed, and potential indicators evaluated using these criteria. (4) Chosen indicators were further researched for ecological relevancy. (5) Final indicators were chosen, field tested, and monitoring sites designated. In Arches, indicators were chosen for monitoring annually (soil crust index, soil compaction, number of used social trails and soil aggregate stability) and every five years (vegetation cover and frequency; ground cover; soil chemistry; and plant tissue chemistry).

  2. 3-dimensional orthodontics visualization system with dental study models and orthopantomograms

    NASA Astrophysics Data System (ADS)

    Zhang, Hua; Ong, S. H.; Foong, K. W. C.; Dhar, T.

    2005-04-01

    The aim of this study is to develop a system that provides 3-dimensional visualization of orthodontic treatments. Dental plaster models and corresponding orthopantomogram (dental panoramic tomogram) are first digitized and fed into the system. A semi-auto segmentation technique is applied to the plaster models to detect the dental arches, tooth interstices and gum margins, which are used to extract individual crown models. 3-dimensional representation of roots, generated by deforming generic tooth models with orthopantomogram using radial basis functions, is attached to corresponding crowns to enable visualization of complete teeth. An optional algorithm to close the gaps between deformed roots and actual crowns by using multi-quadratic radial basis functions is also presented, which is capable of generating smooth mesh representation of complete 3-dimensional teeth. User interface is carefully designed to achieve a flexible system with as much user friendliness as possible. Manual calibration and correction is possible throughout the data processing steps to compensate occasional misbehaviors of automatic procedures. By allowing the users to move and re-arrange individual teeth (with their roots) on a full dentition, this orthodontic visualization system provides an easy and accurate way of simulation and planning of orthodontic treatment. Its capability of presenting 3-dimensional root information with only study models and orthopantomogram is especially useful for patients who do not undergo CT scanning, which is not a routine procedure in most orthodontic cases.

  3. The ARCHES Project

    NASA Astrophysics Data System (ADS)

    Motch, C.; Arches Consortium

    2015-09-01

    The Astronomical Resource Cross-matching for High Energy Studies (ARCHES) project is a FP7-Space funded programme started in 2013 and involving the Observatoire Astronomique de Strasbourg including the CDS (France), the Leibniz- Institut für Astrophysik Potsdam (Germany), the University of Leicester (UK), the Universidad de Cantabria (IFCA, Spain) and the Instituto Nacional de Tecnica Aeroespacial (Spain). ARCHES will provide the international astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large samples of objects extracted from the 3XMM X-ray catalogue of serendipitous sources. The project develops new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues and a multi-wavelength finder for clusters of galaxies. SEDs are based on an enhanced version of the 3XMM catalogue and on a careful selection of the most relevant multi-wavelength archival catalogues. In order to ensure the largest audience, SEDs will be distributed to the international community through CDS services and through the Virtual Observatory. These enhanced resources are tested in the framework of several science cases. More information may be found at http://www.arches-fp7.eu/

  4. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    DOE PAGES

    Myers, C. E.; Yamada, M.; Ji, H.; ...

    2016-11-04

    Here, the loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be appliedmore » to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruption. The verification of magnetic force balance also confirms the low-beta assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical expectations. These two co

  5. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    NASA Astrophysics Data System (ADS)

    Myers, C. E.; Yamada, M.; Ji, H.; Yoo, J.; Jara-Almonte, J.; Fox, W.

    2016-11-01

    The loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be applied to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruptions [Myers et al., Nature 528, 526 (2015)]. The verification of magnetic force balance also confirms the low-β assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical

  6. Public perceptions of dental implants: a qualitative study.

    PubMed

    Wang, Guihua; Gao, Xiaoli; Lo, Edward C M

    2015-07-01

    Dental implants have become a popular option for treating partially dentate or edentulous patients. Information on dental implants is widely available in the public domain and is disseminated through industries and dental practitioners at various levels/disciplines. This qualitative study aimed to evaluate the public's information acquisition and their perceptions of dental implants and the effects of these on their care-seeking and decision making. A purposive sample of 28 adults were recruited to join six focus groups. To be eligible, one must be 35-64 years of age, had never been engaged in dentally related jobs, had at least one missing tooth, and had heard about dental implant but never received dental implant or entered into any dental consultation regarding dental implants. All of the focus groups discussions were transcribed verbatim and subjected to thematic content analysis following a grounded theory approach. Participants acquired information on dental implants through various means, such as patient information boards, printed advertisements, social media, and personal connections. They expected dental implants to restore the patients' appearance, functions, and quality of life to absolute normality. They regarded dental implants as a panacea for all cases of missing teeth, overestimated their functions and longevity, and underestimated the expertise needed to carry out the clinical procedures. They were deterred from seeking dental implant treatment by the high price, invasive procedures, risks, and complications. Members of the public were exposed to information of varying quality and had some unrealistic expectations regarding dental implants. Such perceptions may shape their care-seeking behaviours and decision-making processes in one way or another. The views and experiences gathered in this qualitative study could assist clinicians to better understand the public's perspectives, facilitate constructive patient-dentist communication, and contribute

  7. Thirty-two-year follow-up study of Herbst therapy: a biometric dental cast analysis.

    PubMed

    Pancherz, Hans; Bjerklin, Krister; Lindskog-Stokland, Birgitta; Hansen, Ken

    2014-01-01

    The aim of this study was to analyze the very long-term effects of Herbst treatment on tooth position and occlusion. Fourteen patients from a sample of 22 with Class II Division 1 malocclusions consecutively treated with the banded Herbst appliance were reexamined 32 years after therapy. Dental casts were analyzed from before (T1) and after (T2) treatment, and at 6 years (T3) and 32 years (T4) after treatment. Minor changes in maxillary and mandibular dental arch perimeters and arch widths were seen during treatment (T1-T2) and posttreatment (T2-T4). Mandibular incisor irregularity remained, on average, unchanged from T1 to T2 but increased continuously during the 32-year follow-up period (T2-T4). Class II molar and canine relationships were normalized in most patients from T1 to T2. During the early posttreatment period (T2-T3), there was a minor relapse; during the late posttreatment period (T3-T4), molar and canine relationships remained, on average, unchanged. Overjet and overbite were reduced to normal values in all subjects during treatment (T1-T2). After treatment (T2-T4), overjet remained, on average, unchanged, but overbite increased insignificantly. Thirty-two years after Herbst therapy, overall, acceptable long-term results were seen. Stability was found in 64% of the patients for sagittal molar relationships, in 14% for sagittal canine relationships, in 86% for overjet, and in 86% for overbite. A Class II relapse seemed to be caused by an unstable interdigitation of the occluding teeth, a persisting oral habit, or an insufficient retention regimen after treatment. Most posttreatment changes occurred during the first 6 years after treatment. After the age of 20 years, only minor changes were noted. Long-term posttreatment changes in maxillary and mandibular dental arch perimeters and widths as well as in mandibular incisor irregularity seemed to be independent of treatment and a result of physiologic dentoskeletal changes throughout adulthood. Copyright

  8. [Prosthodontic correction of severe deep vertical overbite combined with dimensional discrepancy of the upper and lower dental arch. 31 years follow-up].

    PubMed

    Kaán, M; Kaán, B; Károlyházy, K

    2001-04-01

    Sz. S. a 39-years-old patient was referred to our department in 1968. Patient's masticatory dysfunction, orofacial pain syndrome and substantial weight loss was due to a combined genuine and acquired deep vertical overbite aggravated by a marked difference between the size of the lower and upper jaw bones. The premolars and molars had already been extracted. The lower incisors bit onto the palatal gingiva in centric occlusion causing direct mechanical irritation on the palate. Consequently the centric occlusion position of the mandible was only defined by the contact between the lower central incisors and the palatal soft tissue. According to the literature this kind of defect can only be corrected by a combined surgical prosthodontic therapy (increasing the mandibular arch by vertical osteotomy combined with bone grafting followed by complex prosthodontic reconstruction). Because patient refused any kind of surgical treatment a special upper full arch bridge was constructed with an extended occlusal surface on the palatal surfaces of the front crowns to provide full occlusal contact for the mandibular anterior teeth. The OVD was raised by 11 mm. The present paper reports the history of a 31 years long prosthodontic treatment and patient's follow up. It is shown how the correct centric occlusion, the masticatory functions, the phonetics and also the esthetics could have been maintained by a series of gradually changing fixed restorations meeting the demands imposed by the continuing tooth loss.

  9. Experimental Study on Cracking, Reinforcement, and Overall Stability of the Xiaowan Super-High Arch Dam

    NASA Astrophysics Data System (ADS)

    Lin, Peng; Zhou, Weiyuan; Liu, Hongyuan

    2015-03-01

    The Xiaowan super-high arch dam has faced challenging construction problems. Here, we provide a scientifically-based reference for applying geomechanical model testing to support the nonlinear design of super-high arch dams. We applied experimental similarity theory and techniques. Based on four 3D geomechanical model tests, the dam stress characteristics, deformation distribution, and the safety factors of the dam foundation were identified and compared. We also analyzed cracking characteristics of the up- and downstream dam surfaces and induced joints in the dam heel, the rock mass failure process of the dam-foundation interface, and the abutments. We propose foundation reinforcement measures for weak rock masses, alteration zones, and other faults in the abutments based on the 3D and plane tests each at a different elevation. The results show that all dam deformations remained normal with no yielding or tensile cracking under a normal water load. The reinforced rock mass increased the crack initial safety in the dam heel and toe by ~20 %. The minimum crack initial safety factor ( K 1) of the dam heel was 1.4. The induced joint in the dam heel contributed to a reduction in tensile stress at the upstream dam heel, improving K 1. Compared with similar projects following reinforcement measures, the abutment stiffness and overall stability of the Xiaowan arch dam satisfy operational requirements. Four years of monitoring operations show that key areas near the dam remained normal and the dam foundation is functioning well. Our results may also be applicable to the design and construction of similar projects worldwide.

  10. Carbon fibre versus metal framework in full-arch immediate loading rehabilitations of the maxilla - a cohort clinical study.

    PubMed

    Pera, F; Pesce, P; Solimano, F; Tealdo, T; Pera, P; Menini, M

    2017-05-01

    Frameworks made of carbon fibre-reinforced composites (CFRC) seem to be a viable alternative to traditional metal frameworks in implant prosthodontics. CFRC provide stiffness, rigidity and optimal biocompatibility. The aim of the present prospective study was to compare carbon fibre frameworks versus metal frameworks used to rigidly splint implants in full-arch immediate loading rehabilitations. Forty-two patients (test group) were rehabilitated with full-arch immediate loading rehabilitations of the upper jaw (total: 170 implants) following the Columbus Bridge Protocol with four to six implants with distal tilted implants. All patients were treated with resin screw-retained full-arch prostheses endowed with carbon fibre frameworks. The mean follow-up was 22 months (range: 18-24). Differences in the absolute change of bone resorption over time between the two implant sides (mesial and distal) were assessed performing a Mann-Whitney U-test. The outcomes were statistically compared with those of patients rehabilitated following the same protocol but using metal frameworks (control group: 34 patients with 163 implants - data reported in Tealdo, Menini, Bevilacqua, Pera, Pesce, Signori, Pera, Int J Prosthodont, 27, 2014, 207). Ten implants failed in the control group (6·1%); none failed in the test group (P = 0·002). A statistically significant difference in the absolute change of bone resorption around the implants was found between the two groups (P = 0·004), with greater mean peri-implant bone resorption in the control group (1 mm) compared to the test group (0·8 mm). Carbon fibre frameworks may be considered as a viable alternative to the metal ones and showed less marginal bone loss around implants and a greater implant survival rate during the observation period. © 2017 John Wiley & Sons Ltd.

  11. Computational Study of Non-Physiological Hemodynamics in the Cephalic Arch

    NASA Astrophysics Data System (ADS)

    Cassel, Kevin; Boghosian, Michael; Mahmoudzadeh, S. M. Javid; Hammes, Mary

    2012-11-01

    Numerical simulations of the unsteady, two-dimensional, incompressible Navier-Stokes equations are performed for the flow in a two-dimensional geometry created from radiological images and Doppler flow measurements of the cephalic arch in dialysis patients with a brachiocephalic fistula (surgically placed direct arterial-venous connection). The simulations are performed before insertion of the fistula and at subsequent time intervals as the cephalic vein arterializes over a period of three to six months. A mature fistula, with increased diameter and flow rate, can exhibit Reynolds numbers that are more than one order of magnitude larger than that of the pre-fistula vein. We evaluate the effect of this increased (physiologically abnormal) Reynolds number on flow structures and wall shear stresses through the curved cephalic arch, which is a site prone to stenosis in fistula patients. The long-term goal is to investigate if the development of initimal hyperplasia and stenoses correlates with wall shear stresses or other hemodynamic variables obtained using computational hemodynamics. Research supported by the National Institute of Diabetes And Digestive And Kidney Diseases of the National Institutes of Health under Award Number R01DK090769.

  12. Dental needs and socioeconomic status associated with utilization of dental services in the presence of dental pain: a case-control study in children.

    PubMed

    Villalobos-Rodelo, Juan José; Medina-Solís, Carlo Eduardo; Maupomé, Gerardo; Lamadrid-Figueroa, Hector; Casanova-Rosado, Alejandro José; Casanova-Rosado, Juan Fernando; Márquez-Corona, María de Lourdes

    2010-01-01

    To identify the effect of unmet dental treatment needs and socioeconomic and sociodemographic variables on the patterns of dental visits in the presence of dental pain in 6- to 12-year-old Mexican schoolchildren. A case-control study included 379 patients that had a dental visit because of dental pain in the 12 months preceding this study and 1,137 controls. Mothers and/or guardians supplied sociodemographic, socioeconomic, and oral health-related information through a questionnaire. The profiles of unmet dental needs and of oral hygiene were ascertained by means of a standardized dental examination administered to participating children. Odds ratios (OR) and 95% confidence intervals (CIs) were calculated with logistic regression. Higher unmet dental needs and lack of health insurance were associated with the experience of dental visits because of dental pain in the preceding 12 months. Boys who attended public schools had a 70% (95% CI = 1.29 to 2.23) higher probability of having had a dental visit in which dental pain was one of the main reasons for attendance, compared to boys attending private schools. The effect for girls was only 28% (95% CI = 1.10 to 1.50) higher for girls attending a public school, compared to girls attending private schools. Older children had a higher occurrence of dental visits because of dental pain than younger children. While higher unmet dental needs and lack of health insurance were strong predictors of having had dental visits because of dental pain in the preceding 12 months, some socioeconomic variables and sociodemographic variables modified these relationships.

  13. Is it possible to use cross-sectional and vertical facial measurements to establish the shape of the mandibular arch?

    PubMed

    El Haje, Ossam Abu; Pompeo, Daniela Daufenback; Furtado, Gisela Crippa; Rivera, Luciana Monti Lima; Paranhos, Luiz Renato

    2014-11-01

    Given the benefits of radiographic cephalometric studies in determining patterns of dental-skeletal-facial normality in orthodontics, the aim of this study was to investigate the association between mandibular dental arch shape and cross-sectional and vertical facial measurements. It was analyzed plaster casts and teleradiographs in frontal and lateral norm belonging to 50 individuals, aged between 15 and 19 years, with no previous history of orthodontic treatment and falling into four of the six Andrews's occlusion keys. The plaster models were scanned (3D) and the images of the dental arches were classified subjectively as oval, triangular and quadrangular by three calibrated examiners, with moderate inter-examiner agreement (Kappa = 0.50). After evaluation of the method error by paired t test (p > 0.05), it was carried out the analysis of cross-sectional and vertical facial measurements to be compared to the shape of the dental arch. Data were subjected to one-way analysis of variance with a significance level of 5%. When the VERT index was compared with the three arch shapes, no measurement showed statistically significant differences (p > 0.05): triangular (0.54); oval (0.43); and quadrangular (0.73); as well as there were no differences (p > 0.05) in the widths of the face (141.20; 141.26; 143.27); maxilla (77.27; 77.57; 78.59) and mandible (105.13; 103.96; 104.28). It can be concluded that there was no correlation between different shapes of the mandibular dental arch and the cross-sectional and vertical facial measurements investigated.

  14. Dental optical tomography with upconversion nanoparticles—a feasibility study

    NASA Astrophysics Data System (ADS)

    Long, Feixiao; Intes, Xavier

    2017-06-01

    Upconversion nanoparticles (UCNPs) have the unique ability to emit multiple colors upon excitation by near-infrared (NIR) light. Herein, we investigate the potential use of UCNPs as contrast agents for dental optical tomography, with a focus on monitoring the status of fillings after dental restoration. The potential of performing tomographic imaging using UCNP emission of visible or NIR light is established. This in silico and ex vivo study paves the way toward employing UCNPs as theranostic agents for dental applications.

  15. Quantitative effects of a nickel-titanium palatal expander on skeletal and dental structures in the primary and mixed dentition: a preliminary study.

    PubMed

    Ferrario, Virgilio F; Garattini, Giovanna; Colombo, Anna; Filippi, Vittorio; Pozzoli, Silvio; Sforza, Chiarella

    2003-08-01

    The present study analysed the six-month effects of a nickel-titanium (NiTi) palatal expander on the dental and palatal structures of four primary (mean age 5.8 years) and nine mixed dentition children (mean age 8.7 years), with a posterior unilateral crossbite. Standardized dental and palatal landmarks were digitized using a three-dimensional (3D) electromagnetic instrument. Collected data were analysed with geometric-mathematical models. During a six-month interval, the natural growth and development of the dental arches and hard tissue palate was negligible, as assessed in seven control children (two in the primary dentition, mean age 4.4 years; five in the mixed dentition, mean age 7.7 years). In all children the crossbite was completely corrected. Indeed, dental expansion was always more than or corresponded to the palatal expansion. A smoothing of the size-independent (shape) palatal curvature in the transverse plane was observed. No differences in maximum palatal height were noted. Symmetrical derotation of the anchorage teeth in a distal direction occurred in almost all children. The inclination of the facial axis of the clinical crown (FACC) in the anatomical transverse plane of those teeth with differences between dental and palatal expansion always showed significant modifications (vestibular inclination up to 16.7 degrees). The clinical crown height of anchorage teeth remained nearly the same in all patients. No significant modifications in mandibular arch size were observed. The increase in maxillary arch width, especially in younger children, was probably due to a combination of different effects: opening of the midpalatal suture, tipping of the alveolar process, and molar tipping.

  16. Preparedness of dental graduates for foundation training: a qualitative study.

    PubMed

    Ali, K; Tredwin, C; Kay, E J; Slade, A; Pooler, J

    2014-08-01

    The aims of this study were to articulate the concept of preparedness of dental graduates for foundation training programme in the United Kingdom and identify the essential attributes of preparedness. A qualitative approach using semi-structured interviews was used to explore the concept of preparedness. The study was carried out in the South West region of England. Participants were recruited from a range of stakeholders in dental education and foundation training using purposive sampling. Participants were recruited using email through appropriate professional channels. Stakeholders included dental students (DS), dental academics (DA), foundation dental practitioners (FDP), foundation trainers (FT), general dental practitioners (GDP) and a postgraduate dental deanery representative (DDR). Interviews were transcribed verbatim and data were imported into NVivo 9 and analysed thematically. Sixteen interviews were carried out with representation from all stakeholder groups. Participants expressed their views on a range of issues related to the preparedness of dental graduates. This study provides useful insights into the concept of preparedness as perceived by the stakeholders. The findings of this study may offer clarity on the essential attributes required by dental graduates upon entry into foundation training.

  17. Digital vs. conventional full-arch implant impressions: a comparative study.

    PubMed

    Amin, Sarah; Weber, Hans Peter; Finkelman, Matthew; El Rafie, Khaled; Kudara, Yukio; Papaspyridakos, Panos

    2016-12-31

    To test whether or not digital full-arch implant impressions with two different intra-oral scanners (CEREC Omnicam and True Definition) have the same accuracy as conventional ones. The hypothesis was that the splinted open-tray impressions would be more accurate than digital full-arch impressions. A stone master cast representing an edentulous mandible using five internal connection implant analogs (Straumann Bone Level RC, Basel, Switzerland) was fabricated. The three median implants were parallel to each other, the far left implant had 10°, and the far right had 15° distal angulation. A splinted open-tray technique was used for the conventional polyether impressions (n = 10) for Group 1. Digital impressions (n = 10) were taken with two intra-oral optical scanners (CEREC Omnicam and 3M True Definition) after connecting polymer scan bodies to the master cast for groups 2 and 3. Master cast and conventional impression test casts were digitized with a high-resolution reference scanner (Activity 880 scanner; Smart Optics, Bochum, Germany) to obtain digital files. Standard tessellation language (STL) datasets from the three test groups of digital and conventional impressions were superimposed with the STL dataset from the master cast to assess the 3D deviations. Deviations were recorded as root-mean-square error. To compare the master cast with conventional and digital impressions at the implant level, Welch's F-test was used together with Games-Howell post hoc test. Group I had a mean value of 167.93 μm (SD 50.37); Group II (Omnicam) had a mean value of 46.41 μm (SD 7.34); Group III (True Definition) had a mean value of 19.32 μm (SD 2.77). Welch's F-test was used together with the Games-Howell test for post hoc comparisons. Welch's F-test showed a significant difference between the groups (P < 0.001). The Games-Howell test showed statistically significant 3D deviations for all three groups (P < 0.001). Full-arch digital implant impressions using True

  18. Do dental students use optimal study strategies?

    PubMed

    McAndrew, Maureen; Kamboj, Rajit S; Pierre, Gaëlle C

    2015-01-01

    Research on human learning has shown that repeated retrieval practice or self-testing maximizes learning. However, recent studies have found undergraduate students to be largely unaware of the benefits of self-testing. The aim of this study was to examine dental students' study strategies and utilization of retrieval techniques for learning. All second-year dental students at New York University College of Dentistry were invited to participate. Of the total 360 students, 66 completed the two-question survey, for a response rate of 18.3%. The first question asked students to choose from a list of twelve study strategies the ones they used and to rank their top five in order of personal preference. Repeated reading was the most frequently used strategy with 83.3% of students reporting that they used it and 43.9% naming it as their top strategy. Of these students, 45.5% indicated that they self-tested while studying, but none indicated it was their number one strategy. The second question asked students how they would study after reading a textbook chapter for the first time. They were asked to choose one option from three possibilities: going back and restudying, self-testing (with the possibility of restudying afterward), or some other strategy. On this question, 25.8% chose restudying, 45.5% chose self-testing, and 28.8% indicated they would use another study strategy. Thus, 54.6% of the students reported they would not test themselves after reading a textbook chapter. Of those who chose self-testing, only seven students indicated they would do so to improve learning. The results of this study suggest that the students lacked sufficient awareness of the superiority of self-testing for learning.

  19. Axial relationship between dental implants and teeth/implants: a radiographic study.

    PubMed

    Machtei, Eli E; Oettinger-Barak, Orit; Horwitz, Jacob

    2014-08-01

    The relationship of dental implants with neighboring teeth will affect both occlusal relationship and distribution of forces; thus, the purpose of this study was to examine implants' axial relationship with adjacent and opposing teeth/implants. Data of dental implants patients was retrieved. Panoramic X rays were digitized. Computer-based software was used to measure the angular relationship between the implants and adjacent/opposing teeth and implants. Data was further sorted by the mode of placement and implants position. 50 patients (219 implants) were included. Mean angle to adjacent tooth/implant was 178.71° ± 9.18° (range 129.7°-206°). Implants were more parallel to adjacent teeth (180.99° ± 1.06°) than to adjacent implants (176.32° ± 0.54°; P = .0001). Mean angular relationship to opposite tooth was 167.88° ± 8.92° (range 137.7°-179.8°). Implants that were placed freehand or with positional guide had similar intra-arch relationship (178.22° and 178.81°, respectively) and similar inter-arch angulations (164.46° and 167.74°). Molars had greater deviation of the angular relationship (175.54°) compared to premolars (181.62°) and incisors (180.55°, P = .0001). Implants placed in the maxilla had smaller axial deviation compared to implants in the mandible (180.41° ± 0.64 vs 177.14° ± 1.02; P = .0081). Good axial relationship may be obtained in most implants placed by an experienced clinician, even when placed freehand. The mandibular posterior region is more prone to axial deviation and as such requires special attention.

  20. Follow-Up Study of 1994 Dental Hygiene Graduates.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In an effort to evaluate the effectiveness of its dental hygiene program, William Rainey Harper College (WRHC), in Illinois, conducted a follow-up study of program graduates from 1994. Surveys were mailed to all 30 1994 dental hygiene associate degree graduates, receiving responses from 77% (n=23). Study findings included the following: (1) all…

  1. Challenges to dental access - England as a case study.

    PubMed

    Bedi, Raman

    2006-06-01

    Access to dental services because of an insufficient workforce is a historic challenge faced by many developing countries. In recent years, however, it has become a major issue for many industrialized countries. The growing demand for cosmetic dentistry, an increase in patients' willingness to pay for dental treatment, and growing numbers of older dentate patients have all put pressure on dental systems. Ways of meeting these challenges and ensuring reasonable dental access will vary from country to country, but the solutions often lie in how the dental workforce is regulated. This case study of the dental reforms currently being implemented in England highlights progress at a particular point in time (Summer 2005). It is clear that it will take a number of years to find a new national dental payment system (the National Health Service) to replace the system which has changed little since 1948. However, the political pressure to address poor access to state-funded dental services calls for more immediate actions. The initial approach was to increase the dental workforce via international recruitment, and in the medium term to increase the number of dental students in training and to expand the numbers of other members of the dental team. An additional stratagem is to retain those already providing dental care under the National Health Service by the introduction of a new method of remuneration. England is trying to improve both access to care and the oral health of the population by creating a workforce more suitable to public demands and changing oral health needs.

  2. Dental implants in medically complex patients-a retrospective study.

    PubMed

    Manor, Yifat; Simon, Roy; Haim, Doron; Garfunkel, Adi; Moses, Ofer

    2017-03-01

    Dental implant insertion for oral rehabilitation is a worldwide procedure for healthy and medically compromised patients. The impact of systemic disease risks on the outcome of implant therapy is unclear, since there are few if any published randomized controlled trials (RCTs). The objective of this study is to investigate the rate of complications and failures following dental implantation in medically compromised patients in order to elucidate risk factors and prevent them. A retrospective cohort study was conducted from patient files treated with dental implantation between the years 2008-2014. The study group consisted of medically complex patients while the control group consisted of healthy patients. Preoperative, intraoperative, and post operative clinical details were retrieved from patients' files. The survival rate and the success rate of the dental implants were evaluated clinically and radiographically. A total of 204 patients (1003 dental implants) were included in the research, in the study group, 93 patients with 528 dental implants and in the control group, 111 patients with 475 dental implants. No significant differences were found between the groups regarding implant failures or complications. The failure rate of dental implants among the patients was 11.8 % in the study group and 16.2 % in the control group (P = 0.04). It was found that patients with a higher number of implants (mean 6.8) had failures compared with patients with a lower number of implants (mean 4.2) regardless of their health status (P < 0.01). We found a similar rate of failure and complications of dental implantation in medically complex patients and in healthy patients. Medically complex patients can undergo dental implantation. There are similar rates of complications and failures of dental implants in medically complex patients and in healthy patients.

  3. Possibility of reconstruction of dental plaster cast from 3D digital study models

    PubMed Central

    2013-01-01

    Objectives To compare traditional plaster casts, digital models and 3D printed copies of dental plaster casts based on various criteria. To determine whether 3D printed copies obtained using open source system RepRap can replace traditional plaster casts in dental practice. To compare and contrast the qualities of two possible 3D printing options – open source system RepRap and commercially available 3D printing. Design and settings A method comparison study on 10 dental plaster casts from the Orthodontic department, Department of Stomatology, 2nd medical Faulty, Charles University Prague, Czech Republic. Material and methods Each of 10 plaster casts were scanned by inEos Blue scanner and the printed on 3D printer RepRap [10 models] and ProJet HD3000 3D printer [1 model]. Linear measurements between selected points on the dental arches of upper and lower jaws on plaster casts and its 3D copy were recorded and statistically analyzed. Results 3D printed copies have many advantages over traditional plaster casts. The precision and accuracy of the RepRap 3D printed copies of plaster casts were confirmed based on the statistical analysis. Although the commercially available 3D printing enables to print more details than the RepRap system, it is expensive and for the purpose of clinical use can be replaced by the cheaper prints obtained from RepRap printed copies. Conclusions Scanning of the traditional plaster casts to obtain a digital model offers a pragmatic approach. The scans can subsequently be used as a template to print the plaster casts as required. Using 3D printers can replace traditional plaster casts primarily due to their accuracy and price. PMID:23721330

  4. Possibility of reconstruction of dental plaster cast from 3D digital study models.

    PubMed

    Kasparova, Magdalena; Grafova, Lucie; Dvorak, Petr; Dostalova, Tatjana; Prochazka, Ales; Eliasova, Hana; Prusa, Josef; Kakawand, Soroush

    2013-05-31

    To compare traditional plaster casts, digital models and 3D printed copies of dental plaster casts based on various criteria. To determine whether 3D printed copies obtained using open source system RepRap can replace traditional plaster casts in dental practice. To compare and contrast the qualities of two possible 3D printing options--source system RepRap and commercially available 3D printing. A method comparison study on 10 dental plaster casts from the Orthodontic department, Department of Stomatology, 2nd medical Faulty, Charles University Prague, Czech Republic. Each of 10 plaster casts were scanned by inEos Blue scanner and the printed on 3D printer RepRap [10 models] and ProJet HD3000 3D printer [1 model]. Linear measurements between selected points on the dental arches of upper and lower jaws on plaster casts and its 3D copy were recorded and statistically analyzed. 3D printed copies have many advantages over traditional plaster casts. The precision and accuracy of the RepRap 3D printed copies of plaster casts were confirmed based on the statistical analysis. Although the commercially available 3D printing enables to print more details than the RepRap system, it is expensive and for the purpose of clinical use can be replaced by the cheaper prints obtained from RepRap printed copies. Scanning of the traditional plaster casts to obtain a digital model offers a pragmatic approach. The scans can subsequently be used as a template to print the plaster casts as required. Using 3D printers can replace traditional plaster casts primarily due to their accuracy and price.

  5. Assessment of gingival thickness with regards to age, gender and arch location

    PubMed Central

    Kolte, Rajashri; Kolte, Abhay; Mahajan, Aaditi

    2014-01-01

    Background: There is a considerable intra and inter-individual variation in both width and thickness of the facial gingiva. As the attached gingiva is an important anatomic and functional landmark in the periodontium, the identification of gingival biotype is important in clinical practice since differences in gingival and osseous architecture have been shown to exhibit a significant impact on the outcome of restorative therapy. Hence, the aim of this study was to determine the variation in width and thickness of facial gingiva in the anterior segment with respect to age, gender and dental arch location. Materials and Methods: 120 subjects were divided into three age groups: The younger age group (16-24 years), the middle age group (25-39 years) and the older age group (>40 years) with 20 males and 20 females in each group. The width of the gingiva was assessed by William's graduated probe and the thickness was determined using transgingival probing in the maxillary and mandibular anterior segment. Results: It was observed that the younger age group had significantly thicker gingiva but less width than that of the older age group. The gingiva was found to be thinner and with less width in females than males. The mandibular arch had thicker gingiva with less width compared to the maxillary arch. Conclusion: In the present study, we concluded that gingival thickness and width varies with age, gender and dental arch location. PMID:25210263

  6. Animal analogues for the study of dental and oral diseases.

    PubMed

    Levy, B M

    1980-01-01

    The usual laboratory animals, such as rats and hamsters, may not fit the criteria for an analogue of human periodontal disease, although they may be useful in the study of dental caries. Rats, hamsters, mice, guinea pigs and rabbits have been the animals of choice in studies relating nutritional deficiencies and excesses to the dental and oral tissues. Gerbils, dogs, cats, horses, cows and fowl are useful in the study of mineralized tissues of teeth and bones. Recently, primate analogues have been developed for the study of periodontal diseaes and dental caries, the two most important dental diseases afflicting man. The use of a wide variety of laboratory animals in basic dental research makes it timely to review some of the guidelines for the selection of specific animals for particular diseases.

  7. Cross-cultural adaptability of Texas dental hygienists and dental hygiene students: a preliminary study.

    PubMed

    Tavoc, Tabitha; Newsom, Ron; DeWald, Janice P

    2009-05-01

    This study sought to determine if statistically significant differences existed among and between licensed dental hygienists and first- and second-year dental hygiene students in Texas on a cross-cultural adaptability measure. The cross-cultural adaptability of licensed dental hygienists and of first- and second-year dental hygiene students attending five randomly selected dental hygiene schools in Texas was investigated. A sample of 289 individuals completed the fifty-item Cross-Cultural Adaptability Inventory (CCAI) and a brief demographic survey, resulting in 278 usable responses. The CCAI yields a total score and four individual subscale scores that describe a person's readiness to interact with people of different cultures. The results revealed no statistically significant differences among the licensed hygienists and students in the first and second years of study and CCAI scores. A statistically significant relationship (r=.148) was found between age and one of the four CCAI subscale scores: flexibility/openness. No other statistically significant relationships were found. The number of years to earn a degree, level of practice, ethnicity, and years employed may not play a significant role in enhancing cross-cultural adaptability. Further research needs to be conducted to determine differences and relationships between and among various dental hygiene groups and their cross-cultural adaptability performance.

  8. The ARCHES project

    NASA Astrophysics Data System (ADS)

    Motch, C.; Arches Consortium

    2014-07-01

    ARCHES (Astronomical Resource Cross-matching for High Energy Studies) is a FP7-Space funded project started in 2013 and involving the Observatoire Astronomique de Strasbourg including the CDS (France), the Leibniz-Institut fuer Astrophysik Potsdam (Germany), the University of Leicester (UK), the Universidad de Cantabria (IFCA, Spain) and the Instituto Nacional de Técnica Aeroespacial (Madrid, Spain). ARCHES aims at providing the international astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large sets of objects extracted from the 3XMM catalogue. The project develops new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues. SEDs are based on an enhanced version of the 3XMM catalogue and on a careful selection of the most relevant multi-wavelength archival catalogues. In order to ensure the largest audience, SEDs will be distributed to the international community through CDS services and through the Virtual Observatory. These enhanced resources are currently tested in the framework of several science cases. An integrated cluster finder is developed at Potsdam, AGN science is studied at Leicester and IFCA while populations of Galactic X-ray sources are investigated at Strasbourg and Madrid.

  9. Determinant factors of Yemeni maxillary arch dimensions.

    PubMed

    Al-Zubair, Nabil Muhsen

    2015-01-01

    Information about maxillary arch and palatal dimensions in human populations is important for clinical orthodontics. This study was conducted to assess the determinants of maxillary arch dimensions in a sample of Yemeni individuals aged 18-25 years. The study sample comprised 214/765 adults (101 women, 113 men) who underwent clinical examination and fulfilled the study criteria. Study models were constructed and evaluated to measure maxillary arch and palatal dimensions. The majority of mean maxillary arch dimensions were significantly greater in men than in women, with inter-second molar distance showing the greatest difference and palatal depth showing the least difference. Measurements of palatal depth and relationships of the canines to one another and to other teeth thus had the widest ranges, implying that these dimensions are the strongest determinants of maxillary arch size.

  10. Seismic performance of arch dams on non-homogeneous and discontinuous foundations (a case study: Karun 4 Dam)

    NASA Astrophysics Data System (ADS)

    Ferdousi, A.

    2017-06-01

    The present study set out to investigate the nonlinear seismic response of the dam-reservoir-rock foundation system, taking into consideration the effects of change in the material properties of discontinuous foundation. To this end, it is important to provide the proper modeling of truncated boundary conditions at the far-end of rock foundation and reservoir fluid domain and to correctly apply the in situ stresses for rock foundation. The nonlinear seismic response of an arch dam mainly depends on the opening and sliding of the dam body's contraction joints and foundation discontinuities, failure of the jointed rock and concrete materials, etc. In this paper, a time domain dynamic analysis of the 3D dam-reservoir-foundation interaction problem was performed by developing a nonlinear Finite Element program. The results of the analysis of Karun-4 Dam revealed the essential role of modeling discontinuities and boundary conditions of rock foundation under seismic excitation.

  11. Arches and contact forces in a granular pile.

    PubMed

    Carlevaro, C M; Pugnaloni, L A

    2012-06-01

    Assemblies of granular particles mechanically stable under their own weight contain arches. These are structural units identified as sets of mutually stable grains. It is generally assumed that these arches shield the weight above them and should bear most of the stress in the system. We test such hypothesis by studying the stress born by in-arch and out-of-arch grains. We show that, indeed, particles in arches withstand larger stresses. In particular, the isotropic stress tends to be larger for in-arch grains whereas the anisotropic component is marginally distinguishable between the two types of particles. The contact force distributions demonstrate that an exponential tail (compatible with the maximization of entropy under no extra constraints) is followed only by the out-of-arch contacts. In-arch contacts seem to be compatible with a Gaussian distribution consistent with a recently introduced approach that takes into account constraints imposed by the local force balance on grains.

  12. Removable dental prostheses and cardiovascular survival: a 15-year follow-up study.

    PubMed

    Janket, S J; Surakka, M; Jones, J A; Lam, A; Schnell, R A; Rose, L M; Walls, A W G; Meurman, J H

    2013-08-01

    In previous studies, increasing number of teeth predicted better survival and the acute needs for dental treatment predicted mortality. We sought to investigate whether restored dentitions by various removable dental prostheses impact cardiovascular (CVD) longevity. Kuopio Oral Health and Heart study was initiated as a cross-sectional investigation with 256 subjects with diagnosed coronary artery disease [CAD] and 250 age- and sex-matched controls without CAD in 1995-1996. The mean age of both groups was 61, 30% were females. We appended mortality follow-up records to the baseline data and formulated this 15-year follow-up study. We examined the relationship between various types of dental prostheses and cardiovascular mortality by proportional hazard regression analyses. We also explored their correlation to oral and systemic inflammatory markers such as asymptotic dental score and C-reactive protein. In a model adjusted for age, sex and smoking, groups having only natural teeth (NT), removable partial denture(s) [PD] and NT, a PD and a full denture [FD], and FD/FD or FD/NT demonstrated the following hazard ratios for mortality (95% confidence interval). NT both arches: 1.00 [reference]; PD and NT: 0.75 [0.22-2.56]; PD and FD: 1.99 [1.05-3.81]; and FD opposed by FD or NT: 1.71 [0.93-3.13], respectively [p for trend=0.05]. Although statistically not significant, those with PD and NT with mean a number of teeth [Nteeth] of 15.4 had better survival compared with those who had all NT [Nteeth=22.5]; while those who had FD and PD [Nteeth=6.5] had shorter longevity than those with FD/FD or FD/NT [Nteeth=3.5]. Although not all subgroups of dental prostheses reached significant relationship with CVD mortality, our study suggests that not only the number [quantity] of remaining teeth but their maintenance [quality] removing potential inflammatory foci, such as pericoronitis or retained root tips, may positively impact on cardiovascular survival. Copyright © 2013 Elsevier

  13. Dental health status and treatment needs of police personnel of a north Indian state: a cross-sectional study.

    PubMed

    Sohi, Rk; Gambhir, Rs; Sogi, Gm; Veeresha, Kl; Randhawa, A

    2014-07-01

    Oral health is an integral part of general health. Police personnel form the backbone for safety and security of a community hence their health is of utmost importance. The present study was conducted to assess the oral health status and treatment needs of police personnel employed in police stations of three districts within 35 km radius around Maharishi Markandeshwar University, Mullana. A cross-sectional study was conducted on all the available police personnel at various police stations. Final sample size comprised of 652 subjects. The data were recorded on modified World Health Organization format (1997). The mean age of subjects was 41.02 years (standard deviation = 12.29), 98.9% (645/652) were males and 1.1% (7/652) were females. The prevalence of dental caries was 54.3% (352/652) and the mean decayed, missing and filled teeth was 3.05. Mean number of teeth requiring filling and extraction were 0.44 and 0.67 respectively. Only 2.92% (19/652) of subjects possessed prosthesis in mandibular arch and a same number of individuals possessed prosthesis in maxillary arch. Regarding highest community periodontal index (CPI) score, 23.6% (153/652) subjects had a healthy periodontium whereas maximum subjects (61.3%, 398/652) had a CPI score 2. Prevalence of dental caries was quite high. Despite a high prosthetic need, only a small number of subjects possessed dental prosthesis. Overall periodontal status was satisfactory with a high number of subjects having completely healthy periodontium.

  14. Clinical trial investigating success rates for polyether and vinyl polysiloxane impressions made with full-arch and dual-arch plastic trays.

    PubMed

    Johnson, Glen H; Mancl, Lloyd A; Schwedhelm, E Ricardo; Verhoef, Douglas R; Lepe, Xavier

    2010-01-01

    Success rates for making fixed prosthodontic impressions based on material and tray selection are not known. The purpose of this clinical study was to compare first impression success rates for 2 types of impression material and 2 impression tray systems. Dual-viscosity impressions were made with a vinyl polysiloxane (VPS) (Aquasil Ultra Monophase/Aquasil Ultra XLV) and a polyether (PE) (Impregum Penta Soft HB/Impregum Garant Soft LB) impression material. The first impression made was evaluated for success or failure using developed criteria. Fifty senior dental students participated. The type of impression material alternated for each new patient. A full-arch perforated plastic (President Tray) or a plastic dual-arch impression tray (Tri-Bite) was used based on clinical guidelines. Impression success rates were compared using logistic regression, fitted using the method of generalized estimating equations (alpha=.05). One hundred ninety-one impressions were evaluated, and the overall success rate was 61% for VPS and 54% for PE (P=.39). Additional regression analyses, adjusted for potential confounders, did not indicate a difference between the 2 systems (P=.35). There was little difference in success rates between the 2 materials when a full-arch tray was used (50% versus 49% success, P=.89), whereas a larger difference was apparent with the use of dual-arch trays (70% success with VPS versus 58% success with PE, P=.21). The most common critical defect was located on the preparation finish line (94%), and the most common operator error was inadequate gingival displacement (15%). There was little difference in success rates between VPS and PE when full-arch impression trays were used, but there was greater success when using VPS with dual-arch trays. For single teeth, the trend favored VPS, but when more than one prepared tooth per impression was involved, the success rate was higher for PE. Copyright 2010 The Editorial Council of the Journal of Prosthetic

  15. Effect of therapeutic insoles on the medial longitudinal arch in patients with flatfoot deformity: a three-dimensional loading computed tomography study

    PubMed Central

    Kido, Masamitsu; Ikoma, Kazuya; Hara, Yusuke; Imai, Kan; Maki, Masahiro; Ikeda, Takumi; Fujiwara, Hiroyoshi; Tokunaga, Daisaku; Inoue, Nozomu; Kubo, Toshikazu

    2014-01-01

    Background Insoles are frequently used in orthotic therapy as the standard conservative treatment for symptomatic flatfoot deformity to rebuild the arch and stabilize the foot. However, the effectiveness of therapeutic insoles remains unclear. In this study, we assessed the effectiveness of therapeutic insoles for flatfoot deformity using subject-based three-dimensional (3D) computed tomography (CT) models by evaluating the load responses of the bones in the medial longitudinal arch in vivo in 3D. Methods We studied eight individuals (16 feet) with mild flatfoot deformity. CT scans were performed on both feet under non-loaded and full-body-loaded conditions, first with accessory insoles and then with therapeutic insoles under the same conditions. Three-dimensional CT models were constructed for the tibia and the tarsal and metatarsal bones of the medial longitudinal arch (i.e., first metatarsal bone, cuneiforms, navicular, talus, and calcaneus). The rotational angles between the tarsal bones were calculated under loading with accessory insoles or therapeutic insoles and compared. Findings Compared with the accessory insoles, the therapeutic insoles significantly suppressed the eversion of the talocalcaneal joint. Interpretation This is the first study to precisely verify the usefulness of therapeutic insoles (arch support and inner wedges) in vivo. PMID:25457972

  16. Effect of therapeutic insoles on the medial longitudinal arch in patients with flatfoot deformity: a three-dimensional loading computed tomography study.

    PubMed

    Kido, Masamitsu; Ikoma, Kazuya; Hara, Yusuke; Imai, Kan; Maki, Masahiro; Ikeda, Takumi; Fujiwara, Hiroyoshi; Tokunaga, Daisaku; Inoue, Nozomu; Kubo, Toshikazu

    2014-12-01

    Insoles are frequently used in orthotic therapy as the standard conservative treatment for symptomatic flatfoot deformity to rebuild the arch and stabilize the foot. However, the effectiveness of therapeutic insoles remains unclear. In this study, we assessed the effectiveness of therapeutic insoles for flatfoot deformity using subject-based three-dimensional (3D) computed tomography (CT) models by evaluating the load responses of the bones in the medial longitudinal arch in vivo in 3D. We studied eight individuals (16 feet) with mild flatfoot deformity. CT scans were performed on both feet under non-loaded and full-body-loaded conditions, first with accessory insoles and then with therapeutic insoles under the same conditions. Three-dimensional CT models were constructed for the tibia and the tarsal and metatarsal bones of the medial longitudinal arch (i.e., first metatarsal bone, cuneiforms, navicular, talus, and calcaneus). The rotational angles between the tarsal bones were calculated under loading with accessory insoles or therapeutic insoles and compared. Compared with the accessory insoles, the therapeutic insoles significantly suppressed the eversion of the talocalcaneal joint. This is the first study to precisely verify the usefulness of therapeutic insoles (arch support and inner wedges) in vivo. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. A study among dental students regarding the factors influenced dental students to choose dentistry as career

    PubMed Central

    AnbuSelvan, Gobichetti Palayam Jagatheeswaran; Gokulnathan, Subramaniam; PrabuRajan, Vilvanathan; RajaRaman, Gangadharan; Kumar, Singaravelu Suresh; Thagavelu, Arthie

    2013-01-01

    Introduction: Career choice is a complex decision for students since it determines the kind of profession that they intend to pursue in life. As students try to make a career choice while in secondary school, they face the problem of matching their career choices with their abilities and school performance. Aims: The purpose of this study was to examine factors influencing career choice among dental college students in private dental collages in Tamil Nadu, India. Settings and Design: The study was conducted using descriptive survey design with a population of 989 students. The data for this study was collected using a questionnaire and interview schedules. Materials and Methods: The data for this study was collected using questionnaire previously used by Swati Shah and Rajaraman and interview schedules. The analysis of the study was based on the factors: Outcome expectations, gender, personal interests, and other factors. Results and Conclusion: The most common reason for among the dental students to choose dental science as their career choice was self-interested followed by didn′t get medicine degree, prestige and gives respect. The least common reasons observed in the study population were inspired by dentists. The findings of this study indicate that availability the most influential factors affecting career choices among students. PMID:23946573

  18. A comparative study of centbucridine and lidocaine in dental extraction.

    PubMed

    Vacharajani, G N; Parikh, N; Paul, T; Satoskar, R S

    1983-01-01

    A randomized double-blind study comparing the efficacy and tolerability of centbucridine (0.5%) with those of lidocaine (2%) as an anaesthetic agent was conducted in the dental outpatient department on patients attending for dental extraction. One hundred and twenty patients were studied. The degree of analgesia attained with centbucridine compared well with that obtained with lidocaine. The compound was well tolerated with no significant changes in the cardiovascular parameters and no serious side-effects.

  19. Knowledge of dental health and diseases among dental patients, a multicentre study in Saudi Arabia.

    PubMed

    Almas, K; Albaker, A; Felembam, N

    2000-01-01

    The aim of this study was to assess the knowledge of dental patients about dental health and diseases. A questionnaire was developed with three sets of questions, 1-general knowledge of dental conditions, 2-use of alternate methods in prevention and treatment of dental diseases, 3-awareness about personal oral health. Six hundred questionnaires were distributed in 6 cities from 4 different regions (i.e. Makkah, Riyadh, Tabuk, Gizan). 367 respondents (61% response rate) constituted 233 (63.5%) male and 134 (36.5%) female with the age range 11-70 years (mean 30 +/- 11.9). The data were analyzed by SPSS version 9.0 and results presented in frequency distributions. 99% male and 96% female considered their teeth for chewing food, 97% male and 96% female knew that increased carbohydrate intake and poor oral hygiene are related to tooth decay, 89% male and 96% female used toothbrush and paste to prevent dental diseases and 75% male and 66% female were regular user of miswak (chewing sticks.) 67% male and 59% female visit dentist, only in pain. 46% used miswak after their meals, only 14% of the subjects used miswak on their lingual and palatal surfaces of teeth, while 38% of the subjects used clove as remedy for toothache, 25.6% used saline and 10% used lemon for bleaching their teeth. 15% considered honey important for their good oral health. Regarding personal oral health, 35% had pain in gums, 36.8% were with bad breath, 28% had tooth hypersensitivity, and almost 50% used toothbrush twice daily while 42% had bleeding gums. It is important to note that knowledge and awareness about dental health and disease conditions are better in male subjects, dietary habits and oral hygiene methods need to be addressed in future investigations. There is a need to provide more health education to female subjects to improve their oral health.

  20. Individualized catenary curves: their relationship to arch form and perimeter.

    PubMed

    Battagel, J M

    1996-02-01

    Study casts of the lower arches of 35 children in whom arch alignment was considered acceptable, were examined using a reflex microscope. Arch perimeter was calculated mathematically from a method which required measurement of the mesio-distal widths of the teeth only. This was described as the 'overlap' method. Arch perimeter was also calculated using individualized catenary curves for each subject. Two calculations were made, recording arch width either at the distal contact points of the first permanent molars or between their mesio-buccal cusps. Arch perimeter measured from the length of the catenary curves was consistently shorter than that calculated by the overlap method. The variation ranged from 0.02 to 4.58 mm. The catenary constructed using the distal molar contacts gave a better representation of the actual arch form: the mean discrepancy was 2.36 mm, compared with 2.86 mm with the second method where arch width was measured between mesio-buccal cusps. Both techniques for calculation of arch perimeter were highly reproducible. The catenary curve only approximated arch form well when the arch was relatively narrow across the inter canine region. For square arches this method was unsatisfactory. It is suggested that alternative techniques would be more reliable and the overlap method described here is considered satisfactory.

  1. Palatal surface and volume in mouth-breathing subjects evaluated with three-dimensional analysis of digital dental casts-a controlled study.

    PubMed

    Lione, Roberta; Franchi, Lorenzo; Huanca Ghislanzoni, Luis Tomas; Primozic, Jasmina; Buongiorno, Marco; Cozza, Paola

    2015-02-01

    To compare the anatomical characteristics of the maxillary arch, identified as palatal surface area and volume, between mouth-breathing and nose-breathing subjects using a three-dimensional (3D) analysis of digital dental casts. Twenty-one Caucasian subjects (14 females and 7 males) with a mean age of 8.5 years [standard deviation (SD) 1.6 years] were selected according to the following criteria: mouth-breathing pattern due to allergic rhinitis, early mixed dentition, skeletal Class I relationship, and pre-pubertal stage of cervical vertebral maturation. This study group (SG) was compared with a control group (CG) of 17 nose-breathing subjects (9 females and 8 males, mean age: 8.5 years; SD: 1.7 years). For each subject, initial dental casts were taken and the upper arch was scanned using a 3D laser scanner. On each digital model, 3D measurements were performed to analyse maxillary arch morphology. Between-group differences were tested with the independent sample Student's t-test (P < 0.05). In mouth-breathing subjects, changes in physiological function of the upper respiratory tract resulted in skeletal adaptations of the maxillary arch. In the SG, both palatal surface area and volume were significantly smaller when compared with values of the CG. In particular, the palatal surface area and palatal volume were, respectively, 13.5 and 27.1 per cent smaller in the SG when compared to the CG. Subjects with prolonged mouth breathing showed a significant reduction of the palatal surface area and volume leading to a different development of the palatal morphology when compared with subjects with normal breathing pattern. © The Author 2014. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. No reliable evidence to guide initial arch wire choice for fixed appliance therapy.

    PubMed

    Flores-Mir, Carlos

    2013-12-01

    The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline and Embase databases were searched. Conference proceedings and abstracts from the British Orthodontic Conference European Orthodontic Conference and the International Association for Dental Research were also searched together with the reference lists of identified studies. Study authors were contacted for additional information. Randomised controlled trials of initial arch wire involving participants with upper and/or lower full arch fixed orthodontic appliances were included. Study selection, data extraction and risk of bias assessment were carried out independently by at least two reviewers. Nine RCTs with 571 participants were included in this review. All trials were at high risk of bias. All trials had at least one potentially confounding factor (such as bracket type, slot size, ligation method, extraction of teeth) which is likely to have influenced the outcome and was not controlled in the trial. None of the trials reported the important adverse outcome of root resorption. The comparisons were made between:Multistrand stainless steel initial arch wires compared to superelastic nickel titanium (NiTi) initial arch wires. There were four trials in this group, with different comparisons and outcomes reported at different times. No meta-analysis was possible. There is insufficient evidence from these trials to determine whether or not there is a difference in either rate of alignment or pain between stainless steel and NiTi initial arch wires.Conventional (stabilised) NiTi initial arch wires compared to superelastic NiTi initial arch wires. There were two trials in this group, one reporting the outcome of alignment over six months and the other reporting pain over one week. There is insufficient evidence from these trials to determine whether or not there is any difference between conventional (stabilised) and superelastic NiTi initial arch

  3. Dental caries among children visiting a mobile dental clinic in South Central Kentucky: a pooled cross-sectional study

    PubMed Central

    2013-01-01

    Background Dental caries is one of the most common chronic childhood diseases affecting a large portion of children in the United States. The prevalence of childhood dental caries in Kentucky is among the highest in the nation. The purposes of this study are to (1) compare sociodemographic differences between caries and no caries groups and (2) investigate factors associated with untreated dental caries among children who visited a mobile dental clinic in South Central Kentucky. Methods Study subjects were children aged 6 to 15 years who participated in the school-based dental sealant program through the mobile dental clinic operated by the Institute for Rural Health at Western Kentucky University between September 2006 and May 2011 (n = 2,453). Descriptive statistics were calculated for sociodemographic factors (age, gender, race/ethnicity, insurance status, and urban versus rural residential location) and caries status. We used chi-square tests to compare sociodemographic differences of children stratified by caries and no caries status as well as three levels of caries severity. We developed a logistic regression model to investigate factors associated with untreated dental caries while controlling for sociodemographic characteristics. Results The proportion of children having untreated dental caries was 49.7% and the mean number of untreated dental caries was 2.0. The proportion of untreated dental caries was higher in older children, children with no insurance and living in rural residential locations, and caries severity was also higher in these groups. Odds ratio indicated that older ages, not having private insurance (having only public, government-sponsored insurance or no insurance at all) and rural residential location were associated with having untreated dental caries after controlling for sociodemographic characteristics of children. Conclusions Untreated dental caries was more likely to be present in older children living in rural areas without

  4. Dental caries among children visiting a mobile dental clinic in South Central Kentucky: a pooled cross-sectional study.

    PubMed

    Dawkins, Erika; Michimi, Akihiko; Ellis-Griffith, Gregory; Peterson, Tina; Carter, Daniel; English, Gary

    2013-05-02

    Dental caries is one of the most common chronic childhood diseases affecting a large portion of children in the United States. The prevalence of childhood dental caries in Kentucky is among the highest in the nation. The purposes of this study are to (1) compare sociodemographic differences between caries and no caries groups and (2) investigate factors associated with untreated dental caries among children who visited a mobile dental clinic in South Central Kentucky. Study subjects were children aged 6 to 15 years who participated in the school-based dental sealant program through the mobile dental clinic operated by the Institute for Rural Health at Western Kentucky University between September 2006 and May 2011 (n = 2,453). Descriptive statistics were calculated for sociodemographic factors (age, gender, race/ethnicity, insurance status, and urban versus rural residential location) and caries status. We used chi-square tests to compare sociodemographic differences of children stratified by caries and no caries status as well as three levels of caries severity. We developed a logistic regression model to investigate factors associated with untreated dental caries while controlling for sociodemographic characteristics. The proportion of children having untreated dental caries was 49.7% and the mean number of untreated dental caries was 2.0. The proportion of untreated dental caries was higher in older children, children with no insurance and living in rural residential locations, and caries severity was also higher in these groups. Odds ratio indicated that older ages, not having private insurance (having only public, government-sponsored insurance or no insurance at all) and rural residential location were associated with having untreated dental caries after controlling for sociodemographic characteristics of children. Untreated dental caries was more likely to be present in older children living in rural areas without insurance. Health interventionists may use

  5. Prospective cohort study of dental implant success rate in patients with AIDS.

    PubMed

    May, Michael Clayton; Andrews, Paul Nielsen; Daher, Shadi; Reebye, Uday Nitin

    2016-12-01

    Oral health care of patients with acquired immune deficiency syndrome (AIDS) due to human immunodeficiency virus (HIV) is a growing area of concern, taking into consideration the increased life expectancy of patients resulting from antiretroviral therapy. There is insufficient literature regarding the impact of dental implants in AIDS patients. This study investigated the long-term clinical outcome of implant placement in patients diagnosed with AIDS. This monocentric study included AIDS patients with CD4 <200 cells/μL, age 18 years or older, and a minimum of one edentulous space requiring implant. All patients in the study were undergoing highly active antiretroviral therapy (HAART). HAART includes nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and integrase strand transfer inhibitors (INSTIs). Typical treatment includes two different NTRIs, along with a third drug, either an INSTI, a PI, or an NNRTI. Bicon dental implants were placed in the patients after medical clearance and were followed up for 5 years. Bicon system implants were chosen because of availability and previous experience with this brand. Implant success criteria are defined as implants that had no clinical mobility at uncovering, no radiographic radiolucency, and allowed for loading and abutment placement. Implant success in AIDS patients was measured over a period of 5 years. Descriptive statistics were used. Sixteen adults met the inclusion criteria (12 males and 4 females) with mean CD4 count as 141.25 (sd 35.5). Thirty-three implants were placed in selected patients. Average time to uncovering was 151 days (sd 25 days). Two of the three failures were maxillary implants in the anterior arch, and the third was in the mandibular posterior arch. The study found a slightly higher failure rate of 10 % in patients with AIDS, compared to widely accepted failure rates in healthy patients at 5-7 %. With

  6. Mediators between education and dental pain: a cross-sectional study to assess the role of dental services utilization.

    PubMed

    Constante, Helena M; Peres, Marco A; Schroeder, Fernanda C; Bastos, João L

    2016-02-01

    This study tested whether the pattern of dental services utilization and the reason for the last dental visit mediate the association between educational attainment and dental pain. This is a cross-sectional analysis (n = 1099) based on data from a prospective cohort study in adults, southern Brazil. The mediating effects were assessed by including interaction terms in logistic regression models and by the KHB method, which estimated the direct, mediated, and total effects of education on dental pain. The prevalence of dental pain was 17.5%. Individuals with less than 12 yr of study who visited the dentist to solve dental problems had a 20% higher odds of reporting dental pain than those with 12 or more years of study, who sought the dentist for preventive reasons. Dental services should also focus on preventive measures, especially if less-educated individuals visit the dentist only to treat problems; this may help reduce the frequency of negative oral health outcomes, including dental pain.

  7. Arching Solar Prominence

    NASA Image and Video Library

    NASA’s STEREO (Ahead) spacecraft watched as an eruptive prominence rose up and arched out in a horseshoe shape far above the Sun’s surface (Aug. 25, 2010). The image and movie show the action in a...

  8. Dental injury after conventional direct laryngoscopy: a prospective observational study.

    PubMed

    Mourão, J; Neto, J; Luís, C; Moreno, C; Barbosa, J; Carvalho, J; Tavares, J

    2013-10-01

    This observational study assessed the frequency and risk factors of dental damage after classic direct laryngoscopy for tracheal intubation in 536 adult patients. The patients' sex, age, height, weight, dental condition, dental mobility, Mallampati class, interincisor gap, thyromental distance, neck circumference, and head and neck extension were recorded. From anaesthesia records, the difficulty of intubation, the number of attempts, type of neuromuscular blocking agent used and duration of anaesthesia were recorded. After anaesthesia, examination revealed that 134 patients (25.0%) had dental damage affecting 162 teeth (147 maxillary; 15 mandibular). Enamel fracture was the commonest injury. In tooth number 21, the interincisor gap (OR 2.5 (95% CI 1.0-5.9)) and in tooth number 22, the number of intubation attempts (OR 5.3 (95% CI 1.3-22.0)) were considered a risk factor for dental injury. Conventional direct laryngoscopy is associated with a strikingly high incidence of dental damage, although specific risk factors remain unclear. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

  9. Clinical Evaluation of Efficacy of CIA and CNA Intrusion Arches.

    PubMed

    Sharma, Swati; Vora, Sambhav; Pandey, Vinisha

    2015-09-01

    Excessive overbite is one of the most common problems that confront the orthodontist. Deep bite can be due to infraocclusion of posterior teeth, supraocclusion of anterior teeth or a combination of the two. Correction of same can be carried out by extrusion of molars, intrusion of incisors or by a combination of both respectively. Various intrusion arches are recommended for correcting deep bite by true intrusion of anterior teeth, Utility arches, Segmental arch, Connecticut Intrusion Arch (CIA) and Connecticut New Arch (CNA). The purpose of this study was to evaluate clinical efficacy of CIA and CNA intrusion arches. Tracings recorded from pre and post-treatment lateral cephalograms of 25 patients treated by CIA (Group I) and another 25 patients treated by CNA (Group II) intrusion arches in deep bite cases after four months of treatment were analysed and findings were recorded. Paired t-test was used to compare pre and post-treatment changes within Groups I and II and unpaired t-test was used to compare treatment changes between Group I and Group II. A P-value of < 0.05 was set for statistical significance. Findings of this study demonstrate that an average of 1mm of intrusion takes place with CIA intrusion arch and 1.3mm with CNA intrusion arch in a period of 4 months. Both intrusion arches do not affect the position of molar in vertical or anteroposterior plane. Both CIA and CNA intrusion arches are effective in bringing about intrusion of lower incisors.

  10. Load response of the medial longitudinal arch in patients with flatfoot deformity: in vivo 3D study

    PubMed Central

    Kido, Masamitsu; Ikoma, Kazuya; Imai, Kan; Tokunaga, Daisaku; Inoue, Nozomu; Kubo, Toshikazu

    2014-01-01

    Background The acquisition of flatfoot by an adult is thought to primarily be caused by posterior tibial tendon dysfunction, although some other causes, such as congenital flexible flatfoot or an accessory navicular, may also be responsible. The objective of this study was to evaluate the bone rotation of each joint in the medial longitudinal arch (MLA) and compare the response in healthy feet with that in flat feet by analyzing the reconstructive three-dimensional (3D) CT image data during weightbearing. Methods CT scans of 20 healthy feet and 24 feet with flatfoot deformity were taken in non-load condition followed by full-body weightbearing condition. Images of the tibia and MLA bones (first metatarsal bone, cuneiforms, navicular, talus, and calcaneus) were reconstructed into 3D models. The volume merge method in three planes was used to calculate the bone-to-bone relative rotations. Findings Under loading conditions, the flatfoot dorsiflexed more in the first tarsometatarsal joint, and everted more in the talonavicular and talocalcaneal joints compared with the healthy foot. The total relative rotation was larger in the flatfoot compared with the healthy foot only in the first tarsometatarsal joint. Interpretation Supporting the MLA in the sagittal direction and the subtalar joint in the coronal direction may be useful for treating flatfoot deformity. The first tarsometatarsal joint may play an important role in diagnosing or treating flatfoot deformity. PMID:23643289

  11. Load response of the medial longitudinal arch in patients with flatfoot deformity: in vivo 3D study.

    PubMed

    Kido, Masamitsu; Ikoma, Kazuya; Imai, Kan; Tokunaga, Daisaku; Inoue, Nozomu; Kubo, Toshikazu

    2013-06-01

    The acquisition of flatfoot by an adult is thought to primarily be caused by posterior tibial tendon dysfunction, although some other causes, such as congenital flexible flatfoot or an accessory navicular, may also be responsible. The objective of this study was to evaluate the bone rotation of each joint in the medial longitudinal arch (MLA) and compare the response in healthy feet with that in flat feet by analyzing the reconstructive three-dimensional (3D) CT image data during weightbearing. CT scans of 20 healthy feet and 24 feet with flatfoot deformity were taken in non-load condition followed by full-body weightbearing condition. Images of the tibia and MLA bones (first metatarsal bone, cuneiforms, navicular, talus, and calcaneus) were reconstructed into 3D models. The volume merge method in three planes was used to calculate the bone-to-bone relative rotations. Under loading conditions, the flatfoot dorsiflexed more in the first tarsometatarsal joint, and everted more in the talonavicular and talocalcaneal joints compared with the healthy foot. The total relative rotation was larger in the flatfoot compared with the healthy foot only in the first tarsometatarsal joint. Supporting the MLA in the sagittal direction and the subtalar joint in the coronal direction may be useful for treating flatfoot deformity. The first tarsometatarsal joint may play an important role in diagnosing or treating flatfoot deformity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Different study conditions between dental students in China and Japan.

    PubMed

    Yan, Xu; Yi, Zhe; Wang, Xu; Jinno, Yohei; Zhang, Xinwen; Koyano, Kiyoshi; Ai, Hongjun

    2015-01-01

    The purpose of this study was to compare the study conditions of dental students towards dental education in China and Japan. 60 students from the Stomatology School of China Medical University and 51 students from the Dental Faculty of Kyushu University, Japan, participated in this study. Information was derived from a self-answered questionnaire consisting of 10 items. More Japanese students (60%) compared to Chinese students (28%) were satisfied with their lives in dental school. For the main reason of discontent, 23.5% of the Japanese students attributed to busy study and lacking of spare time, while 38.3% of the Chinese students indicated small campus lacking of infrastructure. Both students of two countries think they were in big pressure. The main stressor of Japanese students was the examination, but that of Chinese students was anxiety of their future and obtains employment. The main source of tuition and maintenance was family in the both countries, but more Japanese students (25.5%) were dependent on scholarship compared with Chinese students (3.3%). The findings from this study enhance our understanding of study conditions among dental students and help to define strategies to improve student management in both Japan and China.

  13. Different study conditions between dental students in China and Japan

    PubMed Central

    Yan, Xu; Yi, Zhe; Wang, Xu; Jinno, Yohei; Zhang, Xinwen; Koyano, Kiyoshi; Ai, Hongjun

    2015-01-01

    Background: The purpose of this study was to compare the study conditions of dental students towards dental education in China and Japan. Methods: 60 students from the Stomatology School of China Medical University and 51 students from the Dental Faculty of Kyushu University, Japan, participated in this study. Information was derived from a self-answered questionnaire consisting of 10 items. Results: More Japanese students (60%) compared to Chinese students (28%) were satisfied with their lives in dental school. For the main reason of discontent, 23.5% of the Japanese students attributed to busy study and lacking of spare time, while 38.3% of the Chinese students indicated small campus lacking of infrastructure. Conclusions: Both students of two countries think they were in big pressure. The main stressor of Japanese students was the examination, but that of Chinese students was anxiety of their future and obtains employment. The main source of tuition and maintenance was family in the both countries, but more Japanese students (25.5%) were dependent on scholarship compared with Chinese students (3.3%). Clinical Implications: The findings from this study enhance our understanding of study conditions among dental students and help to define strategies to improve student management in both Japan and China. PMID:26379955

  14. Neurological symptoms among dental assistants: a cross-sectional study

    PubMed Central

    Moen, BE; Hollund, BE; Riise, T

    2008-01-01

    Background Dental assistants help the dentist in preparing material for filling teeth. Amalgam was the filling material mostly commonly used in Norway before 1980, and declined to about 5% of all fillings in 2005. Amalgam is usually an alloy of silver, copper, tin and mercury. Copper amalgam, giving particularly high exposure to mercury was used in Norway until 1994. Metallic mercury is neurotoxic. Few studies of the health of dental assistants exist, despite their exposure to mercury. There are questions about the existence of possible chronic neurological symptoms today within this working group, due to this exposure. The aim of this study was to compare the occurrence of neurological symptoms among dental assistants likely to be exposed to mercury from work with dental filling material, compared to similar health personnel with no such exposure. Methods All dental assistants still at work and born before 1970 registered in the archives of a trade union in Hordaland county of Norway were invited to participate (response rate 68%, n = 41), as well as a similar number of randomly selected assistant nurses (response rate 87%, n = 64) in the same age group. The participants completed a self-administered, mailed questionnaire, with questions about demographic variables, life-style factors, musculoskeletal, neurological and psychosomatic symptoms (Euroquest). Results The dental assistants reported significant higher occurrence of neurological symptoms; psychosomatic symptoms, problems with memory, concentration, fatigue and sleep disturbance, but not for mood. This was found by analyses of variance, adjusting for age, education, alcohol consumption, smoking and personality traits. For each specific neurological symptom, adjusted logistic regression analyses were performed, showing that these symptoms were mainly from arms, hands, legs and balance organs. Conclusion There is a possibility that the higher occurrence of neurological symptoms among the dental assistants

  15. Neurological symptoms among dental assistants: a cross-sectional study.

    PubMed

    Moen, Be; Hollund, Be; Riise, T

    2008-05-18

    Dental assistants help the dentist in preparing material for filling teeth. Amalgam was the filling material mostly commonly used in Norway before 1980, and declined to about 5% of all fillings in 2005. Amalgam is usually an alloy of silver, copper, tin and mercury. Copper amalgam, giving particularly high exposure to mercury was used in Norway until 1994. Metallic mercury is neurotoxic. Few studies of the health of dental assistants exist, despite their exposure to mercury. There are questions about the existence of possible chronic neurological symptoms today within this working group, due to this exposure. The aim of this study was to compare the occurrence of neurological symptoms among dental assistants likely to be exposed to mercury from work with dental filling material, compared to similar health personnel with no such exposure. All dental assistants still at work and born before 1970 registered in the archives of a trade union in Hordaland county of Norway were invited to participate (response rate 68%, n = 41), as well as a similar number of randomly selected assistant nurses (response rate 87%, n = 64) in the same age group. The participants completed a self-administered, mailed questionnaire, with questions about demographic variables, life-style factors, musculoskeletal, neurological and psychosomatic symptoms (Euroquest). The dental assistants reported significant higher occurrence of neurological symptoms; psychosomatic symptoms, problems with memory, concentration, fatigue and sleep disturbance, but not for mood. This was found by analyses of variance, adjusting for age, education, alcohol consumption, smoking and personality traits. For each specific neurological symptom, adjusted logistic regression analyses were performed, showing that these symptoms were mainly from arms, hands, legs and balance organs. There is a possibility that the higher occurrence of neurological symptoms among the dental assistants may be related to their previous work

  16. [Mouth diseases and dental materials: potential for study with cytofluorometry].

    PubMed

    Tabaj, D; Braulin, L; Frezzini, C; Visintini, E; Maglione, M; Melato, M

    2000-01-01

    The potential dental materials have of inducing mouth diseases is well known, and various methods have been developed to investigate this phenomenon. Among these there are histological studies of the pulp and periodontium exposed to dental materials, both in vivo and in vitro in humans and animals. Other studies are based on the clinical observation of the effects induced by dental materials. Aim of the paper is to evaluate the use of flow cytometry to analyse crevicular fluid to study its content in terms of inflammatory cells and inflammation mediators. Samples of crevicular fluid were collected by aspiration using a bevelled needle mounted on a 5 ml syringe from patients without periodontitis and with periodontitis and multiple heterogeneous dental restorations. This method was adopted since it allows to place the cells of the fluid in suspension. Part of the fluid was analysed by cytology and part by flow cytometry. In the patients without periodontal disease cytological examination revealed the presence of desquamated epithelial cells and colonies of cocci, rods and spirochaetae. In the patients with periodontal disease the same examination revealed, besides the above, the presence of inflammatory cells. Flow cytometry confirmed the findings of cytological examination, thus proving to be an effective method for studying crevicular fluid. This method allows to identify specific inflammatory cells or mediators of inflammation in crevicular fluid and may therefore prove to be very useful in the study of alterations induced by some dental materials at the level of the gingival sulcus.

  17. Preliminary cone-beam computed tomography study evaluating dental and skeletal changes after treatment with a mandibular Schwarz appliance.

    PubMed

    Tai, Kiyoshi; Hotokezaka, Hitoshi; Park, Jae Hyun; Tai, Hisako; Miyajima, Kuniaki; Choi, Matthew; Kai, Lisa M; Mishima, Katsuaki

    2010-09-01

    The purpose of this study was to evaluate the efficacy of the Schwarz appliance with a new method of superimposing detailed cone-beam computed tomography (CBCT) images. The subjects were 28 patients with Angle Class I molar relationships and crowding; they were randomly divided into 2 groups: 14 expanded and 14 nonexpanded patients. Three-dimensional Rugle CBCT software (Medic Engineering, Kyoto, Japan) was used to measure 10 reference points before treatment (T0) and during the retention period of approximately 9 months after 6 to 12 months of expansion (T1). Cephalometric and cast measurements were used to evaluate the treatments in both groups. Also, the mandibular widths of both groups were measured along an axial plane at 2 levels below the cementoenamel junction from a CBCT scan. Differences between the 2 groups at T0 and T1 were analyzed by using the Mann-Whitney U test. The dental arch (including tooth root apices) had expanded; however, alveolar bone expansion was only up to 2 mm below the cementoenamel junction. There was a statistically significant (P <0.05) difference between the groups in terms of crown, cementoenamel junction, root, and upper alveolar process. However, no significant (P >0.05) differences were observed in the interwidths of the mandibular body, zygomatic bones, condylar heads, or mandibular antegonial notches. In the mandibular cast measurements, arch crowding and arch perimeter showed statistically significant changes in the expanded group. The buccal mandibular width and lingual mandibular width values had significant changes as measured from a point 2 mm below the cementoenamel junction. The findings suggest that the Schwarz appliance primarily affected the dentoalveolar complex, but it had little effect on either the mandibular body or any associated structures. In addition, the molar center of rotation was observed to be below the root apex. 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  18. Veneered zirconia inlay-retained fixed dental prostheses: 10-Year results from a prospective clinical study.

    PubMed

    Rathmann, Friederike; Bömicke, Wolfgang; Rammelsberg, Peter; Ohlmann, Brigitte

    2017-09-01

    The purpose of this study was to evaluate the 10-year clinical performance of zirconia-based inlay-retained fixed dental prostheses (IRFDP). For replacement of a molar in 27 patients, 30 IRFDP were luted by use of different cements, Panavia F (Kuraray Europe GmbH) or Multilink Automix (Ivoclar Vivadent GmbH), with use of inlay/inlay, inlay/full-crown, or inlay/partial-crown retainers for anchorage. Frameworks were milled from yttria-stabilized zirconia (IPS e.maxZirCAD; Ivoclar Vivadent GmbH) and fully veneered with pressable ceramic (IPS e.max ZirPress; Ivoclar Vivadent GmbH). Before luting, the IRFDP were silica-coated (Rocatec; 3M Espe) and silanized (Monobond S; Ivoclar Vivadent GmbH). Complications (for example, chipping or delamination of the veneering ceramic, debonding, secondary caries, endodontic treatment, and abutment tooth fracture) and failure were reported, by use of standardized report forms, 2 weeks, 6 months, and 1, 2, and 10 years after cementation. Statistical analysis included Kaplan-Meier survival and success (complication-free survival) and Cox regression analysis (α=0.05 for all). During the 10-year observation period, the complications most often observed were chipping of the veneer and debonding. Twenty-five restorations failed and one participant dropped out. Cumulative 10-year survival and success were 12.1% and 0%, respectively. The design of the retainer, use of a dental dam, choice of cement, and location in the dental arch had no statistically significant effect on the occurrence of complications. Use of fully veneered zirconia-based IRFDP with this technique cannot be recommended. A large incidence of complications and poor survival were observed for fully veneered zirconia-based IRFDP, revealing an urgent need for further design improvements for this type of restoration. This, again, emphasizes the need for testing of new restoration designs in clinical trials before implementation in general dental practice. Copyright © 2017

  19. Case study of linking dental and medical healthcare records.

    PubMed

    Theis, Mary Kay; Reid, Robert J; Chaudhari, Monica; Newton, Katherine M; Spangler, Leslie; Grossman, David C; Inge, Ronald E

    2010-02-01

    To link the administrative data of a large dental carrier and an integrated health plan in Washington State to conduct an observational study of diabetes and periodontal disease. Evaluation of variable suitability, testing of linkage variables, and performing an n - 1 deterministic linkage strategy. We examined a variety of administrative data variables for their consistency over time and their information richness to use as matching variables. After choosing social security number, date of birth, first name, and last name, we tested their reliability as linking variables among a population with dual dental and medical insurance. Lastly, we performed four n - 1 deterministic linkage steps to obtain our study population. With a success match rate of more than 96% with the 4 test variables, we extracted the entire population who met the study criteria with the understanding that only a subset would successfully link. We linked 78,230 individuals (55.2% of the Group Health Cooperative population). Of these matches more than 50% occurred within a last name-first name-birth date deterministic match. Employer groups who provide dental-medical benefits for their employees send identical administrative data to dental and healthcare plans. The n - 1 deterministic linkage was accomplished by using a relatively straightforward approach because these data were fairly homogeneous and of high quality. Until medical care and dental care are integrated, it is possible to link these data to assess the impact of oral disease on overall health.

  20. Maxillary versus mandibular arch form differences in human permanent dentition assessed by Euclidean-distance matrix analysis.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G

    1994-02-01

    Euclidean-distance matrix analysis (EDMA) was used to analyse the dental arch form in 50 men and 45 women aged 20-27 yr with sound dentitions. Fourteen landmarks, corresponding to the centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar), were identified on the dental casts of subjects. All the possible linear distances between pairs of teeth were computed and maxillary/mandibular arch differences within sex were tested by EDMA. In both sexes, the maxillary arch was larger than the mandibular arch; arch shape was also significantly different. All teeth contributed to the shape difference between arches regardless of gender. EDMA also separated the influence of anterior and posterior teeth in the determination of upper/lower arch characteristics.

  1. [Association between malocclusion and dissatisfaction with dental and gingival appearance: study with Brazilian adolescents].

    PubMed

    Borges, Carolina Marques; Peres, Marco Aurélio; Peres, Karen Glazer

    2010-12-01

    In spite of the high prevalence of malocclusion in adolescents reported worldwide, there are few studies that have investigated the association between normative malocclusion and self-rated dental and gingival appearance among adolescents. The aim of this study was to identify the association between normative malocclusion and dissatisfaction with dental and gingival appearance among Brazilian adolescents. A cross-sectional study was carried out with adolescents aged 15 to 19 years (n= 16,126) living in 250 towns of all five Brazilian regions. Dissatisfaction with dental and gingival appearance was the outcome. The main explanatory variable was malocclusion assessed by using the Dental Aesthetic Index - DAI. The other explanatory variables included were per capita family income, schooling delay, study conditions, sex, age, skin color, dental outcomes (untreated dental caries, missing teeth due dental caries, dental calculus, fluorosis, and dental pain) and use of dental services. Simple and multivariable Poisson regression analyses were performed. Dissatisfaction with dental appearance reached 11.4% (95%CI: 10.4-12.5) of the entire sample. All levels of malocclusion were associated with dissatisfaction with dental appearance. Adjusted multivariable analysis showed that dissatisfaction with dental appearance among individuals affected by severe or very severe malocclusion was respectively 40% and 80% higher than among those with normal occlusion. Malocclusion was associated with dissatisfaction with dental and gingival appearance. The results contribute to include self-rated dental appearance criteria in orthodontic treatment decision, mainly within the National Health System - SUS.

  2. Dental Prophylaxis and Osteoradionecrosis: A Population-Based Study.

    PubMed

    Chang, C T; Liu, S P; Muo, C H; Tsai, C H; Huang, Y F

    2017-05-01

    The aim of this study was to investigate the association of different dental prophylactic modalities and osteoradionecrosis (ORN) and determine the risk of ORN under different timing periods of scaling, with the use chlorhexidine mouth rinse after surgery and with different strategies of fluoride gel application in head and neck cancer (HNC) participants. A cohort of 18,231 HNC participants, including 941 ORN patients and 17,290 matched control cases, were enrolled from a Longitudinal Health Insurance Database for Catastrophic Illness Patients (LHID-CIP) in Taiwan. Based on different dental prophylactic modalities before radiotherapy, including chlorhexidine mouth rinse, scaling, and fluoride gel, all HNC subjects were stratified into different groups. The Cox proportional hazard regression was used to compare ORN incidences under different dental prophylactic modalities. The results revealed that scaling and chlorhexidine mouth rinse were significantly related to ORN risk ( P = 0.004 and P < 0.0001). Chlorhexidine mouth rinse was highly correlated to ORN occurrence (hazard ratio [HR], 1.83-2.66), as exposure increased the risk by 2.43-fold among oral cancer patients, regardless of whether they had received major oral surgery or not. Oral cancer patients receiving scaling within 2 wk before radiotherapy increased their incidence of ORN by 1.28-fold compared with patients who had not undergone scaling within 6 mo. There is no significance of fluoride application for dental prophylaxis in increasing ORN occurrence. In conclusion, dental prophylaxis before radiotherapy is strongly correlated to ORN in HNC patients. Chlorhexidine exposure and dental scaling within 2 wk before radiotherapy is significantly related to ORN risk, especially in oral cancer patients. The use of 1.1% NaF topical application did not significantly increase the risk of ORN in HNC patients. An optimal dental prophylaxis protocol to reduce ORN should concern cancer location, cautious prescription

  3. Comparative Findings in School Systems with Differing Approaches to Dental Health Education. Special Dental Health Study - Spring 1967.

    ERIC Educational Resources Information Center

    Myers, Sharon E.; Downs, Robert A.

    A study was done to determine what differences, if any, existed in the level of dental health knowledge between pupils at continuous resident (CR) schools (schools which employed a full-time dental hygienist) and pupils at nonresident (NR) schools (schools which provided only classroom instruction by the teacher). Demographic characteristics of…

  4. Comparative evaluation of border molding, using two different techniques in maxillary edentulous arches - An in vivo study.

    PubMed

    Yarapatineni, Rameshbabu; Vilekar, Abhishek; Kumar, J Phani; Kumar, G Ajay; Aravind, Prasad; Kumar, P Anil

    2013-12-01

    This study was undertaken to compare the retention between sectional border molding using low fusing greenstick compound and single step border molding using condensation silicone (putty) impression material in three stages- A. Immediately following border molding, B. After final impression and C. With the finished permanent denture base. In this study evaluation of retentive values of sectional border molding (Group I) (custom impression trays border molded with green stick compound ) and single step border molding (Group II) ( border molding with condensation silicone (putty) impression material ). In both techniques definitive wash impression were made with light body condensation silicone and permanent denture base with heat cure polymerization resin. Group II was significantly higher (mean=8011.43) than Group I (mean=5777.43) in test-A. The t-value (1.5883) infers that there was significant difference between Group I and Group II (p =0.15). Group I was significantly higher (mean=6718.57) than Group II (mean=5224.29) in test -B. The t-value (1.6909) infers that there was significant difference between Group I and Group II (p=0.17). Group II was higher (mean=4025.14) than Group I (mean=3835.07) in test -C. The t-value was 0.1239. But it was found to be statistically insignificant (p=0.005). Within the limitation of this clinical study border molding custom tray with low fusing green stick compound provided similar retention as compared to custom impression tray with condensation silicone in permanent denture base. How to cite this article: Yarapatineni R, Vilekar A, Kumar JP, Kumar GA, Aravind P, Kumar PA. Comparative evaluation of border molding, using two different techniques in maxillary edentulous arches - An in vivo study. J Int Oral Health 2013; 5(6):82-7 .

  5. Comparative evaluation of border molding, using two different techniques in maxillary edentulous arches - An in vivo study

    PubMed Central

    Yarapatineni, Rameshbabu; Vilekar, Abhishek; Kumar, J Phani; Kumar, G Ajay; Aravind, Prasad; Kumar, P Anil

    2013-01-01

    Background: This study was undertaken to compare the retention between sectional border molding using low fusing greenstick compound and single step border molding using condensation silicone (putty) impression material in three stages- A. Immediately following border molding, B. After final impression and C. With the finished permanent denture base. Materials & Methods: In this study evaluation of retentive values of sectional border molding (Group I) (custom impression trays border molded with green stick compound ) and single step border molding (Group II) ( border molding with condensation silicone (putty) impression material ). In both techniques definitive wash impression were made with light body condensation silicone and permanent denture base with heat cure polymerization resin. Results: Group II was significantly higher (mean=8011.43) than Group I (mean=5777.43) in test-A. The t-value (1.5883) infers that there was significant difference between Group I and Group II (p =0.15). Group I was significantly higher (mean=6718.57) than Group II (mean=5224.29) in test -B. The t-value (1.6909) infers that there was significant difference between Group I and Group II (p=0.17). Group II was higher (mean=4025.14) than Group I (mean=3835.07) in test -C. The t-value was 0.1239. But it was found to be statistically insignificant (p=0.005). Conclusion: Within the limitation of this clinical study border molding custom tray with low fusing green stick compound provided similar retention as compared to custom impression tray with condensation silicone in permanent denture base. How to cite this article: Yarapatineni R, Vilekar A, Kumar JP, Kumar GA, Aravind P, Kumar PA. Comparative evaluation of border molding, using two different techniques in maxillary edentulous arches - An in vivo study. J Int Oral Health 2013; 5(6):82-7 . PMID:24453450

  6. Awareness of forensic odontology among dental practitioners in Chennai: A knowledge, attitude, practice study.

    PubMed

    Preethi, S; Einstein, A; Sivapathasundharam, B

    2011-07-01

    The aim of the study is to analyze the knowledge, attitude and practice of forensic odontology among dental practitioners in Chennai. A cross-sectional study was conducted in a sample of 322 dental practitioners in Chennai and data was collected by means of a questionnaire. Twenty-one percent of the dental practitioners did not maintain dental records in their clinic/workplace, with only 12% of the practitioners maintaining complete records. Ninety-three percent of dental practitioners were not maintaining dental records for more than seven years. The significance of ante-mortem records in identifying deceased suspects was not known to 17% of the dental practitioners. Forty percent of the dental practitioners were not aware of child abuse and the actions to be taken. Dental age estimation was not known to 41% of the dental practitioners. Thirty-eight percent of the practitioners were unaware of the accurate method of individual identification. About 18% of the dental practitioners did not know the significance of bite mark patterns of the teeth. Ninety-three percent of the practitioners lacked formal training in collecting, evaluating and presenting dental evidence. Thirty percent of dental practitioners did not know they can testify as an expert witness in the court of law. Forty percent of the dental practitioners were unaware of identifying the age and gender of an individual in mass disasters. Our study revealed inadequate knowledge, poor attitude and lack of practice of forensic odontology prevailing among the dental practitioners in Chennai.

  7. Comparison of conventional study model measurements and 3D digital study model measurements from laser scanned dental impressions

    NASA Astrophysics Data System (ADS)

    Nugrahani, F.; Jazaldi, F.; Noerhadi, N. A. I.

    2017-08-01

    The field of orthodontics is always evolving,and this includes the use of innovative technology. One type of orthodontic technology is the development of three-dimensional (3D) digital study models that replace conventional study models made by stone. This study aims to compare the mesio-distal teeth width, intercanine width, and intermolar width measurements between a 3D digital study model and a conventional study model. Twelve sets of upper arch dental impressions were taken from subjects with non-crowding teeth. The impressions were taken twice, once with alginate and once with polivinylsiloxane. The alginate impressions used in the conventional study model and the polivinylsiloxane impressions were scanned to obtain the 3D digital study model. Scanning was performed using a laser triangulation scanner device assembled by the School of Electrical Engineering and Informatics at the Institut Teknologi Bandung and David Laser Scan software. For the conventional model, themesio-distal width, intercanine width, and intermolar width were measured using digital calipers; in the 3D digital study model they were measured using software. There were no significant differences between the mesio-distal width, intercanine width, and intermolar width measurments between the conventional and 3D digital study models (p>0.05). Thus, measurements using 3D digital study models are as accurate as those obtained from conventional study models

  8. Terahertz pulsed imaging study of dental caries

    NASA Astrophysics Data System (ADS)

    Karagoz, Burcu; Altan, Hakan; Kamburoglu, Kıvanç

    2015-07-01

    Current diagnostic techniques in dentistry rely predominantly on X-rays to monitor dental caries. Terahertz Pulsed Imaging (TPI) has great potential for medical applications since it is a nondestructive imaging method. It does not cause any ionization hazard on biological samples due to low energy of THz radiation. Even though it is strongly absorbed by water which exhibits very unique chemical and physical properties that contribute to strong interaction with THz radiation, teeth can still be investigated in three dimensions. Recent investigations suggest that this method can be used in the early identification of dental diseases and imperfections in the tooth structure without the hazards of using techniques which rely on x-rays. We constructed a continuous wave (CW) and time-domain reflection mode raster scan THz imaging system that enables us to investigate various teeth samples in two or three dimensions. The samples comprised of either slices of individual tooth samples or rows of teeth embedded in wax, and the imaging was done by scanning the sample across the focus of the THz beam. 2D images were generated by acquiring the intensity of the THz radiation at each pixel, while 3D images were generated by collecting the amplitude of the reflected signal at each pixel. After analyzing the measurements in both the spatial and frequency domains, the results suggest that the THz pulse is sensitive to variations in the structure of the samples that suggest that this method can be useful in detecting the presence of caries.

  9. The ARCHES Integrated Cluster Finder

    NASA Astrophysics Data System (ADS)

    Mints, A.; Schwope, A.

    2014-07-01

    We are developing a tool to search for galaxy clusters associated with X-ray sources from the 3XMM catalog within the ARCHES project (Astronomical Resource cross-matching for High-Energy Studies). We make use of the new cross-matching tool developed for ARCHES to select galaxies in different catalogs around X-ray positions and then try to find clusters by searching for overdensities in the multi-color space. Colors are related to redshifts using spectroscopic data for passively evolving galaxies from the BOSS and VIPERS catalogs. So far we are making use of SDSS, UKIDSS, WISE, and CFHTLS photometric catalogs, but the method can easily be expanded to other data as well (e.g. Pan-STARRS and DES). We present test results of our tool performed on reference samples from the XMM/SDSS cluster survey (Takey et al 2012) and the NORAS/REFLEX surveys.

  10. Digital Evaluation of Three Splinting Materials Used to Fabricate Verification Jigs for Full-Arch Implant Prostheses: A Comparative Study.

    PubMed

    Papaspyridakos, Panos; Kim, Yong-Jeong; Finkelman, Matthew; El-Rafie, Khaled; Weber, Hans-Peter

    2017-04-01

    The primary aim of this study was to assess the accuracy of different splinting materials to make implant cast verification jigs. The secondary aim was to assess the effect of 20° implant angulation on the accuracy of casts. An edentulous mandibular arch with five internal connection tissue level implants served as control. The three implants in the anterior region were parallel to each other and the two implants in the posterior region were distally tilted 20° bilaterally. Verification jigs were fabricated with three different materials by splinting prefabricated bars to temporary abutments, resulting in three different groups (n = 15 specimens). Test casts were fabricated with low expansion type IV stone, and subsequently digitized with reference scanner. The STL files from the test casts and the control were superimposed, in order to determine the three-dimensional (3D) deviations. Group 1 (GC Pattern Resin) had a mean (SD) value of 36.59 (12.47) μm; Group 2 (Fixpeed Resin) had a mean (SD) value of 35.9 (10.13) μm; and Group 3 (Triad Gel) had a mean (SD) of 34.12 (7.10) μm. One-way ANOVA showed no statistically significant difference between groups (p = 0.790). For the comparative analysis of the effect of implant angulation, data were normally distributed for Groups 1 and 3 (GC Resin and Triad Gel), but not for group 2 (Fixpeed Resin). The difference between parallel and tilted implants was significant for all three groups: GC Resin (p = 0.024; paired t-test), Fixpeed Resin (p = 0.002; Wilcoxon signed-rank test), and Triad Gel (p = 0.002; paired t-test). There were no statistically significant differences between the 3D deviations of the test casts fabricated from verification jigs made by three materials (GC Pattern Resin, Fixpeed Resin, and Triad Gel). Parallel implants had nominally significantly less 3D deviations compared with 20° distally tilted implants, but not clinically significant. The results of the present study indicate

  11. Arch development with trans-force lingual appliances.

    PubMed

    Clark, William J

    2005-01-01

    Trans-Force lingual appliances are designed to correct arch form in patients with contracted dental arches. Interceptive treatment with this new series of pre-activated lingual appliances offers new possibilities for arch development, in combination with fixed appliances. Palatal and lingual appliances insert in horizontal lingual sheaths in molar bands. No activation is required after the appliance is fitted, and this principle is extended to a series of appliances for sagittal and transverse arch development. Both sagittal and transverse appliances have additional components to achieve 3-way expansion where this is indicated. The invisible lingual appliances may be used in correction of all classes of malocclusion at any stage of development, from mixed dentition through permanent dentition, and this approach has wide indications in adult treatment.

  12. A 20-year study of dentists' and dental hygienists' assessment of dental caries lesions in bite-wing radiographs.

    PubMed

    Gabre, Pia; Birring, Eva; Gahnberg, Lars

    2006-01-01

    Epidemiological data reveal that the prevalence of dental caries in western countries has decreased in recent decades. The aim of this study was to investigate how dentists and dental hygienists assess dental caries lesions in bite-wing radiographs between 1983 and 2003. All dentists and dental hygienists in Public Dental Health in Uppsala County were offered to take part in the study. The participants assessed manifest and initial caries lesions in eight bite-wing radiographs from three patients individually. An X-ray viewer and binoculars were used. The assessments were repeated in the same radiographs every five years, a total of five times, between 1983 and 2003. In the different test occasions 80-103 dentists and 11-48 dental hygienists participated. The registration of dental caries changed between 1983 and 2003. The number of manifest lesions registered by dentists decreased between 1983 and 1988, but were stable after 1988. Dental hygienists showed no changes in the registration of manifest lesions during the study. Initial lesions registered by dentists and dental hygienists increased between 1988 and 1998. Assessments of initial caries lesions displayed a wider range than manifest lesions. Increasing age and more years in the profession resulted in fewer registered initial caries lesions. Dental hygienists had a tendency to register less caries than dentists. In conclusion, the result of the study indicate that inclusion of initial caries lesions in epidemiological reports should lead to a reduction in reliability. The changes in assessments of manifest caries lesions that took place in the 19805s should be considered when epidemiological data are evaluated.

  13. 9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ARTICULATED HANGER AND GUARDRAIL. VIEW TO SOUTHEAST. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  14. 10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, HANGERS AND GUARDRAIL. VIEW TO SOUTH. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  15. BRIDGE ABUTMENTS WITH ARCH SEGMENTS ON RIVER BOTTOM. ARCHES COLLAPSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BRIDGE ABUTMENTS WITH ARCH SEGMENTS ON RIVER BOTTOM. ARCHES COLLAPSED AROUND EIGHT YEARS BEFORE THIS DATE. - Whittlesey Road Bridge, Spanning Black River at Whittlesey Road, Lyons Falls, Lewis County, NY

  16. A Golden Arch

    NASA Image and Video Library

    2015-08-06

    This still image from an animation from NASA GSFC Solar Dynamics Observatory shows magnetically charged particles forming a nicely symmetrical arch at the edge of the Sun as they followed the magnetic field lines of an active region Aug.4-5, 2015. Before long the arch begins to fade, but a fainter and taller arch appears for a time in the same place. Note that several other bright active regions display similar kinds of loops above them. These images of ionized iron at about one million degrees were taken in a wavelength of extreme ultraviolet light. The video covers about 30 hours of activity. http://photojournal.jpl.nasa.gov/catalog/PIA19874

  17. Dental superimposition: a pilot study for standardising the method.

    PubMed

    De Angelis, D; Cattaneo, C; Grandi, M

    2007-11-01

    Dental superimposition is becoming more and more important because of the increasing number of illegal immigrants (at least in Italy), with no clinical history, no personal effects or relatives useful for genetic comparison, whose friends and acquaintances can usually only produce photographs. Very few authors have been involved in devising and using this method. The goal of the present study is to establish whether it is possible, and under which conditions, to identify individuals by dental superimposition of teeth visible in an ante-mortem photograph and dental casts of an unidentified body, and to develop a protocol for the spatial orientation analysis of the dentition and qualitative and semi-quantitative analysis of superimpositions. A non-mathematical scoring system has been applied to each superimposition as a first step towards the optimisation of a cheap, quick, semi-quantitative method of identifying individuals when other more used methods are not applicable.

  18. Asymmetry in dentition and shape of pharyngeal arches in the clonal fish Chrosomus eos-neogaeus: Phenotypic plasticity and developmental instability

    PubMed Central

    Leung, Christelle; Duclos, Kevin Karl; Grünbaum, Thomas; Cloutier, Richard

    2017-01-01

    The effect of the environment may result in different developmental outcomes. Extrinsic signals can modify developmental pathways and result in alternative phenotypes (phenotypic plasticity). The environment can also be interpreted as a stressor and increase developmental instability (developmental noise). Directional and fluctuating asymmetry provide a conceptual background to discriminate between these results. This study aims at assessing whether variation in dentition and shape of pharyngeal arches of the clonal fish Chrosomus eos-neogaeus results from developmental instability or environmentally induced changes. A total of 262 specimens of the Chrosomus eos-neogaeus complex from 12 natural sites were analysed. X-ray microcomputed tomography (X-ray micro-CT) was used to visualize the pharyngeal arches in situ with high resolution. Variation in the number of pharyngeal teeth is high in hybrids in contrast to the relative stability observed in both parental species. The basal dental formula is symmetric while the most frequent alternative dental formula is asymmetric. Within one lineage, large variation in the proportion of individuals bearing basal or alternative dental formulae was observed among sites in the absence of genetic difference. Both dentition and arch shape of this hybrid lineage were explained significantly by environmental differences. Only individuals bearing asymmetric dental formula displayed fluctuating asymmetry as well as directional left-right asymmetry for the arches. The hybrids appeared sensitive to environmental signals and intraspecific variation on pharyngeal teeth was not random but reflects phenotypic plasticity. Altogether, these results support the influence of the environment as a trigger for an alternative developmental pathway resulting in left-right asymmetry in dentition and shape of pharyngeal arches. PMID:28380079

  19. Asymmetry in dentition and shape of pharyngeal arches in the clonal fish Chrosomus eos-neogaeus: Phenotypic plasticity and developmental instability.

    PubMed

    Leung, Christelle; Duclos, Kevin Karl; Grünbaum, Thomas; Cloutier, Richard; Angers, Bernard

    2017-01-01

    The effect of the environment may result in different developmental outcomes. Extrinsic signals can modify developmental pathways and result in alternative phenotypes (phenotypic plasticity). The environment can also be interpreted as a stressor and increase developmental instability (developmental noise). Directional and fluctuating asymmetry provide a conceptual background to discriminate between these results. This study aims at assessing whether variation in dentition and shape of pharyngeal arches of the clonal fish Chrosomus eos-neogaeus results from developmental instability or environmentally induced changes. A total of 262 specimens of the Chrosomus eos-neogaeus complex from 12 natural sites were analysed. X-ray microcomputed tomography (X-ray micro-CT) was used to visualize the pharyngeal arches in situ with high resolution. Variation in the number of pharyngeal teeth is high in hybrids in contrast to the relative stability observed in both parental species. The basal dental formula is symmetric while the most frequent alternative dental formula is asymmetric. Within one lineage, large variation in the proportion of individuals bearing basal or alternative dental formulae was observed among sites in the absence of genetic difference. Both dentition and arch shape of this hybrid lineage were explained significantly by environmental differences. Only individuals bearing asymmetric dental formula displayed fluctuating asymmetry as well as directional left-right asymmetry for the arches. The hybrids appeared sensitive to environmental signals and intraspecific variation on pharyngeal teeth was not random but reflects phenotypic plasticity. Altogether, these results support the influence of the environment as a trigger for an alternative developmental pathway resulting in left-right asymmetry in dentition and shape of pharyngeal arches.

  20. Anterior maxillary segmental distraction for correction of maxillary hypoplasia and dental crowding in cleft palate patients: a preliminary report.

    PubMed

    Wang, X-X; Wang, X; Li, Z-L; Yi, B; Liang, C; Jia, Y-L; Zou, B-S

    2009-12-01

    To evaluate the feasibility of anterior maxillary segmental distraction (AMSD) to correct maxillary hypoplasia and severe dental crowding in cleft lip and palate (CLP) patients, 7 patients (average age 16.4 years) with maxillary hypoplasia, shortened maxillary dental arch length and severe anterior dental crowding secondary to CLP were selected for this study. After anterior maxillary segmental osteotomy, 3 patients were treated using bilateral internal distraction devices, and 4 patients were treated using rigid external distraction devices. Photographs and radiographs were taken to review the improvement in facial profile and occlusion after distraction. An average 10.25 mm anterior maxillary advancement was obtained in all patients after 10-23 days of distraction and 9-16 weeks of consolidation. The sella-nasion-point A (SNA) angle increased from 69.5 degrees to 79.6 degrees. Midface convexity was greatly improved and velopharyngeal competence was preserved. The maxillary dental arch length was greatly increased by 10.1 mm (P<0.01). Dental crowding and malocclusion were corrected by orthodontic treatment. These results show that AMSD can effectively correct the hypoplastic maxilla and severe dental crowding associated with CLP by increasing the midface convexity and dental arch length while preserving velopharyngeal function, and dental crowding can be corrected without requiring tooth extraction.

  1. [Study of the prevalence of dental fluorosis in Aracaju].

    PubMed

    Carvalho, Ricardo Wathson Feitosa de; Valois, Roberta Barreto Vieira; Santos, Cléa Núbia Albuquerque; Marcellini, Paulo Sérgio; Bonjardim, Leonardo Rigoldi; Oliveira, Cristiane Costa da Cunha; Barretto, Sandra Regina; Gonçalves, Suzane Rodrigues Jacinto

    2010-06-01

    With the aims of determining the prevalence dental fluorosis in the city of Aracaju, Sergipe State, 196 students were submitted to an oral exam, utilizing the Dean's index. It was concluded that the prevalence of dental fluorosis in students ranging from 5 to 15 years old in the city of Aracaju, Sergipe State was of 8.16%, not implying in a risk to public health. However, similar studies must be done regularly, besides orientation to governmental departments responsible for water fluoridation, so that the level considered excellent for this area can be respected, avoiding such problem to occur.

  2. Magnetic Field Arches

    NASA Image and Video Library

    2016-09-28

    When an active region rotated into a profile view, SDO was able to capture the magnificent loops arching above an active region (Sept. 28-29, 2016). Active region are areas of strong magnetic fields. The magnetic field lines above these regions are illuminated by charged particles spiraling along them. The images were taken in a wavelength of extreme ultraviolet light. The video covers 12 hours of activity. The Earth was inset to give a sense of the scale of these towering arches. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21101

  3. Biomechanical investigation of the supraorbital arch - a transient FEA study on the impact of physical blows

    PubMed Central

    2014-01-01

    Introduction As fractures of the supraorbital region are far less common than midfacial or orbital fractures, a study was initiated to investigate whether fist blows could lead to fractures similar to those often seen in the midface. Methods A detailed skull model and an impactor resembling a fist were created and a fist blow to the supraorbital region was simulated. A transient finite element analysis was carried out to calculate von Mises stresses, peak force, and impact time. Results Within the contact zone of skull and impactor critical stress values could be seen which lay at the lower yield border for potential fractures. A second much lower stress zone was depicted in the anterior-medial orbital roof. Conclusions In this simulation a fist punch, which could generate distinct fractures in the midface and naso-ethmoid-orbital region, would only reach the limits of a small fracture in the supraorbital region. The reason is seen in the strong bony architecture. Much higher forces are needed to create severe trauma in the upper face which is supported by clinical findings. Finite element analysis is the method of choice to investigate the impact of trauma on the human skeleton. PMID:24745339

  4. Biomechanical investigation of the supraorbital arch - a transient FEA study on the impact of physical blows.

    PubMed

    Huempfner-Hierl, Heike; Schaller, Andreas; Hierl, Thomas

    2014-04-21

    As fractures of the supraorbital region are far less common than midfacial or orbital fractures, a study was initiated to investigate whether fist blows could lead to fractures similar to those often seen in the midface. A detailed skull model and an impactor resembling a fist were created and a fist blow to the supraorbital region was simulated. A transient finite element analysis was carried out to calculate von Mises stresses, peak force, and impact time. Within the contact zone of skull and impactor critical stress values could be seen which lay at the lower yield border for potential fractures. A second much lower stress zone was depicted in the anterior-medial orbital roof. In this simulation a fist punch, which could generate distinct fractures in the midface and naso-ethmoid-orbital region, would only reach the limits of a small fracture in the supraorbital region. The reason is seen in the strong bony architecture. Much higher forces are needed to create severe trauma in the upper face which is supported by clinical findings. Finite element analysis is the method of choice to investigate the impact of trauma on the human skeleton.

  5. Transcultural skills content in a dental curriculum: a comparative study.

    PubMed

    Mariño, R; Hawthorne, L; Morgan, M; Ismail, M; Bata, M

    2012-02-01

    Australia has the highest proportion of immigrants in the world (24% of the population is overseas-born, compared to 22% in New Zealand, 19% in Canada and 12% in the USA). In this context, dental students have become increasingly diverse in a milieu where patients are derived from increasingly diverse backgrounds. The study aims to analyse the degree to which transcultural and communication skills content is currently embedded in the medical, physiotherapy and dental curricula at a major Australian university.   Undergraduate dental, medical and physiotherapy curricula were compared and critically assessed. Researchers considered the amount of transcultural and communication skills content, the number of formal contact hours for each course and the number of teaching staff involved. In addition, 21 interviews were conducted with staff at the three schools, who were involved in the curriculum development process. The medical and physiotherapy curricula had an explicit focus on transcultural and communication skills as a major and continuing element, delivered by teaching staff from a wide variety of academic and professional backgrounds. In contrast, the dental course showed an under-representation of transcultural and communication skills content which was taught by a limited number of staff from the School of Dental Science. In marked contrast to medical and physiotherapy curricula, transcultural and communication skills content had a low formal profile in the dental curriculum. A curriculum review process may be a positive step towards the development of a new training curriculum giving higher priority to transcultural and communication skills to support more effective workforce development. © 2010 John Wiley & Sons A/S.

  6. [Traumatic dental injuries in Serbian children--epidemiological study].

    PubMed

    Vuković, Ana; Marković, Dejan; Petrović, Bojan; Apostolović, Mirjana; Golijanin, Ranko; Kanjevac, Tatjana; Stojković, Branislava; Perić, Tamara; Blagojević, Duska

    2013-01-01

    Comprehensive epidemiological data regarding factors associated with traumatic dental injuries are scarce. The aim of the present study was to assess the frequency and analyze the factors associated with traumatic dental injuries in Serbian children. Research included children and adolescents with traumatic dental injury aged 0-19 year during the period from 2003 to 2010, in four University Dental Centres in Serbia: Belgrade, Nis, Novi Sad and Kragujevac. Patient history, demographic, clinical and radiographic data were obtained from dental trauma forms. Total of 2,194 patients (748 girls, 1,446 boys) (chi2 = 222.1; p < 0.01) with 3,077 injured teeth in permanent and 953 in primary dentition were observed. Most of patients were aged 7 to 12 years (n = 1,191). The most frequent injuries in primary and permanent dentition were dislocations (87.4%) and teeth fractures (50.8%), respectively (chi2 = 706.1; p < 0.01). The most frequent mechanism of injury was fall in children aged 0 to 12 years, while the collisions were most frequent in adolescents (53.9%). The most frequent injuries in adolescents were inflicted outdoor (66.8%), while the injuries in children aged 0 to 3 years occurred at home (68.2%), (chi2 = 360.8; p < 0.01). The most frequent injuries in girls were accidental (48.3%), and in boys these were sport injuries (20.4%) and violence (10.4%) (chi2 = 79.9; p < 0.01). The most frequent cause of injury in children aged 0 to 3 years was accidental (75.6%), while in adolescents it was sport (34.1%) (chi2 = 1102.7; p < 0.01). Dental injuries in preschool children most frequently resulted from fall at home. Schoolchildren most frequently injured teeth outdoor during play. Violence and sport injuries were most frequent cause of injury in adolescents.

  7. Study of a large arched structure of interstellar H I in the southern Milky Way

    NASA Astrophysics Data System (ADS)

    Olano, C. A.

    2017-10-01

    We have revisited the sky region delimited by 290° < l < 320° and 3° < b < 17°, which includes a large arc of neutral hydrogen (H i), and extended the study region using the Leiden-Argentine-Bonn H I survey. The H I arc is almost an open downward semi-circumference of ≈10° of radius, with the symmetry axis perpendicular to the Galactic plane and the vertex at (l, b) ≈ (308°, 11°). The velocity component in the spectra of the 21 cm H I line that reveals the H I arc has a mean radial velocity (local standard of rest) of - 19 ± 2 km s - 1. Analysing H I maps covering the region lying below the arc (b < 0), we have investigated whether the arc could be interpreted as the cap of an expanding shell originated by a strong explosion occurred below the Galactic plane. The lower cap of the shell would have been blown out into the Galactic halo. In these conditions, the evolution of the shock wave and the associated shell was calculated by means of the Kompaneets approximation. By comparing the model's predictions with the observations, we obtained that the distance, age and H I mass of the shell would be 640 pc, 9.3 × 106 yr and 3.4 × 105 M⊙, respectively. The shell's sizes along and perpendicular to the Galactic plane would be 295 pc and ≈ 540 pc, respectively. By means of the model, we obtained that the energy of the explosion that gave origin to the shell would be around 5 × 1050 erg. Data from future surveys and from Gaia are expected to help confirming the proposed model. Other interstellar complexes of the region are also considered in relation to the H I shell.

  8. The Foot's Arch and the Energetics of Human Locomotion.

    PubMed

    Stearne, Sarah M; McDonald, Kirsty A; Alderson, Jacqueline A; North, Ian; Oxnard, Charles E; Rubenson, Jonas

    2016-01-19

    The energy-sparing spring theory of the foot's arch has become central to interpretations of the foot's mechanical function and evolution. Using a novel insole technique that restricted compression of the foot's longitudinal arch, this study provides the first direct evidence that arch compression/recoil during locomotion contributes to lowering energy cost. Restricting arch compression near maximally (~80%) during moderate-speed (2.7 ms(-1)) level running increased metabolic cost by + 6.0% (p < 0.001, d = 0.67; unaffected by foot strike technique). A simple model shows that the metabolic energy saved by the arch is largely explained by the passive-elastic work it supplies that would otherwise be done by active muscle. Both experimental and model data confirm that it is the end-range of arch compression that dictates the energy-saving role of the arch. Restricting arch compression had no effect on the cost of walking or incline running (3°), commensurate with the smaller role of passive-elastic mechanics in these gaits. These findings substantiate the elastic energy-saving role of the longitudinal arch during running, and suggest that arch supports used in some footwear and orthotics may increase the cost of running.

  9. Conserved odontogenic potential in embryonic dental tissues.

    PubMed

    Hu, X; Lin, C; Shen, B; Ruan, N; Guan, Z; Chen, Y; Zhang, Y

    2014-05-01

    Classic tissue recombination studies have demonstrated that, in the early developing mouse tooth germ, the odontogenic potential, known as the tooth-inductive capability, resides initially in the dental epithelium and then shifts to the dental mesenchyme. However, it remains unknown if human embryonic dental tissues also acquire such odontogenic potential. Here we present evidence that human embryonic dental tissues indeed possess similar tooth-inductive capability. We found that human dental epithelium from the cap stage but not the bell stage was able to induce tooth formation when confronted with human embryonic lip mesenchyme. In contrast, human dental mesenchyme from the bell stage but not the cap stage could induce mouse embryonic second-arch epithelium as well as human keratinocyte stem cells, to become enamel-secreting ameloblasts. We showed that neither post-natal human dental pulp stem cells (DPSCs) nor stem cells from human exfoliated deciduous teeth (SHED) possess odontogenic potential or are odontogenic-competent. Our results demonstrate a conservation of odontogenic potential in mouse and human dental tissues during early tooth development, and will have an implication in the future generation of stem-cell-based bioengineered human replacement teeth.

  10. Planning predicts dental service attendance and the effect is moderated by dental anxiety and educational status: findings from a one-year prospective study.

    PubMed

    Pakpour, Amir H; Gellert, Paul; Asefzadeh, Saeed; Sniehotta, Falko F

    2014-07-01

    The aim of this study was to investigate whether planning a dental appointment is a predictor of actual dental visits over a one-year period when controlling for past attendance, demographic factors, and dental health beliefs. In addition, the planning-attendance association was explored to determine whether dental anxiety and educational status moderated this relationship. A total of N = 1,422 adults with a mean age of M = 44.4 (SD = 11.0) years and resident in Iran participated in a prospective study over a one-year period. The primary outcome was self-reported dental appointment attendance at one-year follow-up, which was validated using clinical records. Action planning, coping planning, health beliefs, age, dental insurance, income, dental health status, dental anxiety, and years of education were assessed at baseline by self-report questionnaire. Data were analysed using multivariate logistic regression. Action planning and coping planning were significantly associated with dental appointment attendance at one-year follow-up. Planning a dental appointment was more predictive of dental appointment attendance for people with higher levels of education and lower dental anxiety. The findings of this study suggest that implementation of the behaviour change technique planning into routine dental practice may have the potential to increase dental appointment attendance rates. © 2014 The International Association of Applied Psychology.

  11. An overview of characteristics of registered studies on dental implants.

    PubMed

    Gajendrareddy, Praveenkumar; Elangovan, Satheesh; Rampa, Sankeerth; Allareddy, Veeratrishul; Lee, Min Kyeong; Nalliah, Romesh P; Allareddy, Veerasathpurush

    2014-09-01

    Clinical trials serve as the empirical basis for clinical decision making. The objective of the current study is to provide an overview of clinical trials examining dental implant outcomes. All registered studies on Dental Implants were selected for analysis. The clinicaltrials.gov website was used to query the characteristics of registered studies. The search term used was dental implants. As of the study conduct date (01/01/2014), a total of 205 studies on dental implants were registered. These included 168 interventional and 37 observational studies. Results were available for only 14 studies. All observational studies and 98.8% of interventional studies included both male and female subjects. Close to 60% of studies had sample sizes between 1 and 50. NIH was listed as funding source in only 5 interventional studies and 3 observational studies. 80% of interventional studies were randomized. However, double masking was reported in only 15% of interventional studies with majority being open labeled. ClinicalTrials.gov registry was created with the intention of increasing the transparency of conducted or ongoing clinical studies and to minimize publication bias commonly seen with industry-sponsored studies. Results of the current study showed that a predominating number of registered studies are funded by industry and other sources, very few registered studies have made their results public, and the ClinicalTrials.gov registry does not provide sufficient information on the quality of study design and thus precluding the public and researchers to judge on the quality of registered studies and publication bias. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Comparative Clinical Study of Conventional Dental Implants and Mini Dental Implants for Mandibular Overdentures: A Randomized Clinical Trial.

    PubMed

    Aunmeungtong, Weerapan; Kumchai, Thongnard; Strietzel, Frank P; Reichart, Peter A; Khongkhunthian, Pathawee

    2017-04-01

    Dental implant-retained overdentures have been chosen as the treatment of choice for complete mandibular removable dentures. Dental implants, such as mini dental implants, and components for retaining overdentures, are commercially available. However, comparative clinical studies comparing mini dental implants and conventional dental implants using different attachment for implant-retained overdentures have not been well documented. To compare the clinical outcomes of using two mini dental implants with Equator(®) attachments, four mini dental implants with Equator attachments, or two conventional dental implants with ball attachments, by means of a randomized clinical trial. Sixty patients received implant-retained mandibular overdentures in the interforaminal region. The patients were divided into three groups. In Groups 1 and 2, two and four mini dental implants, respectively, were placed and immediately loaded by overdentures, using Equator(®) attachments. In Group 3, conventional implants were placed. After osseointegration, the implants were loaded by overdentures, using ball attachments. The study distribution was randomized and double-blinded. Outcome measures included changes in radiological peri-implant bone level from surgery to 12 months postinsertion, prosthodontic complications and patient satisfaction. The cumulative survival rate in the three clinical groups after one year was 100%. There was no significant difference (p < 0.05) in clinical results regarding the number (two or four) of mini dental implants with Equator attachments. However, there was a significant difference in marginal bone loss and patient satisfaction between those receiving mini dental implants with Equator attachments and conventional dental implants with ball attachments. The marginal bone resorption in Group 3 was significantly higher than in Groups 1 and 2 (p < 0.05); there were no significant differences between Groups 1 and 2. There was no significant difference

  13. Dental Hygienists' Experiences with Motivational Interviewing: A Qualitative Study.

    PubMed

    Curry-Chiu, Margaret E; Catley, Delwyn; Voelker, Marsha A; Bray, Kimberly Krust

    2015-08-01

    The effectiveness of Motivational Interviewing (MI) to change health behaviors is well documented. Previous studies support use of MI to change oral health behaviors in the areas of early childhood caries and periodontal diseases, but research is limited due to the sparse number of oral health care providers with training in MI. The University of Missouri-Kansas City (UMKC) formally integrated MI training into its dental hygiene curriculum five years ago. Summative program evaluation of UMKC's MI training shows that it effectively equips graduates with MI skills. The aim of this qualitative study was to use semi-structured interviews with nine program alumni to provide insight into the experiences of MI-trained dental hygienists in clinical practice. All interviews were captured with a digital voice recorder, were transcribed, and were resubmitted to the interviewees for checking. Five themes emerged from the data analysis: salience, best practices, barriers, facilitators, and lessons learned. These dental hygienists strongly valued and embraced the spirit of MI. They reported feeling strongly that it should be part of all dental hygiene curricula, and they upheld MI as a best practice. The participants approved of their MI instruction as a whole but felt it was difficult and sometimes not viable in practice. They reported that MI training had improved their communication skills and increased treatment acceptance. Time, difficulty, and managing patient resistance were the most often cited barriers, while a supportive climate and creating a routine were the most often cited facilitators.

  14. Microbial contamination of dental unit waterlines in dental practices in Hesse, Germany: A cross-sectional study.

    PubMed

    Arvand, Mardjan; Hack, Alfons

    2013-03-01

    The quality of water from dental units is of considerable importance since patients and dental staff are regularly exposed to water and aerosols generated from the dental unit. This study analyzed the microbial quality of water obtained for periodical monitoring from 56 dental units in different dental practices in Hesse. Contamination by Legionella spp., Pseudomonas aeruginosa, and increased total colony counts were detected in 27.8%, 3.5%, and 17% of samples. Legionella pneumophila serogroup 1 accounted for 28% of Legionella isolates. The Legionella concentration was >100 cfu/100 ml in 84% of contaminated samples. Samples collected from an instrument channel were more frequently contaminated by Legionella than those from cup filler (41.7% vs. 18.6%, p = 0.02). After release of these results, decontamination measures were performed in units that had revealed unsatisfactory results. The outcome of the intervention was followed-up by microbiological analysis. At follow-up, 65.2% and 72.7% of waterlines that had previously been contaminated by Legionella or had shown increased total colony counts were free of contamination. Our results show a high rate of contamination of water from dental units in dental practices in Hesse. They highlight the risk of exposure for patients and personnel and the need for effective strategies to reduce microbial contamination.

  15. Dental pain, oral impacts and perceived need for dental treatment in Tanzanian school students: a cross-sectional study

    PubMed Central

    Mashoto, Kijakazi O; Åstrøm, Anne N; David, Jamil; Masalu, Joyce R

    2009-01-01

    Background Dental caries, dental pain and reported oral problems influence people's oral quality of life and thus their perceived need for dental care. So far there is scant information as to the psychosocial impacts of dental diseases and the perceived treatment need in child populations of sub-Saharan Africa. Objectives Focusing on primary school students in Kilwa, Tanzania, a district deprived of dental services and with low fluoride concentration in drinking water, this study aimed to assess the prevalence of dental pain and oral impacts on daily performances (OIDP), and to describe the distribution of OIDP by socio-demographics, dental caries, dental pain and reported oral problems. The relationship of perceived need estimates with OIDP was also investigated. Methods A cross-sectional study was conducted in 2008. A total of 1745 students (mean age 13.8 yr, sd = 1.67) completed an extensive personal interview and under-went clinical examination. The impacts on daily performances were assessed using a Kiswahili version of the Child-OIDP instrument and caries experience was recorded using WHO (1997) criteria. Results A total of 36.2% (41.3% urban and 31.4% rural, p < 0.001) reported at least one OIDP. The prevalence of dental caries was 17.4%, dental pain 36.4%, oral problems 54.1% and perceived need for dental treatment 46.8% in urban students. Corresponding estimates in rural students were 20.8%, 24.4%, 43.3% and 43.8%. Adjusted OR for reporting oral impacts if having dental pain ranged from 2.5 (95% CI 1.8–3.6) (problem smiling) to 4.7 (95% CI 3.4–6.5) (problem sleeping),- if having oral problems, from 1.9 (95% CI 1.3–2.6) (problem sleeping) to 3.8 (95% CI 2.7–5.2) (problem eating) and if having dental caries from 1.5 (95% CI 1.1–2.0) (problem eating) to 2.2 (95% CI 1.5–2.9) (problem sleeping). Students who perceived need for dental care were less likely to be females (OR = 0.8, 95% CI 0.6–0.9) and more likely to have impacts on eating (OR = 1

  16. Dental pain, oral impacts and perceived need for dental treatment in Tanzanian school students: a cross-sectional study.

    PubMed

    Mashoto, Kijakazi O; Astrøm, Anne N; David, Jamil; Masalu, Joyce R

    2009-07-30

    Dental caries, dental pain and reported oral problems influence people's oral quality of life and thus their perceived need for dental care. So far there is scant information as to the psychosocial impacts of dental diseases and the perceived treatment need in child populations of sub-Saharan Africa. Focusing on primary school students in Kilwa, Tanzania, a district deprived of dental services and with low fluoride concentration in drinking water, this study aimed to assess the prevalence of dental pain and oral impacts on daily performances (OIDP), and to describe the distribution of OIDP by socio-demographics, dental caries, dental pain and reported oral problems. The relationship of perceived need estimates with OIDP was also investigated. A cross-sectional study was conducted in 2008. A total of 1745 students (mean age 13.8 yr, sd = 1.67) completed an extensive personal interview and under-went clinical examination. The impacts on daily performances were assessed using a Kiswahili version of the Child-OIDP instrument and caries experience was recorded using WHO (1997) criteria. A total of 36.2% (41.3% urban and 31.4% rural, p < 0.001) reported at least one OIDP. The prevalence of dental caries was 17.4%, dental pain 36.4%, oral problems 54.1% and perceived need for dental treatment 46.8% in urban students. Corresponding estimates in rural students were 20.8%, 24.4%, 43.3% and 43.8%. Adjusted OR for reporting oral impacts if having dental pain ranged from 2.5 (95% CI 1.8-3.6) (problem smiling) to 4.7 (95% CI 3.4-6.5) (problem sleeping),--if having oral problems, from 1.9 (95% CI 1.3-2.6) (problem sleeping) to 3.8 (95% CI 2.7-5.2) (problem eating) and if having dental caries from 1.5 (95% CI 1.1-2.0) (problem eating) to 2.2 (95% CI 1.5-2.9) (problem sleeping). Students who perceived need for dental care were less likely to be females (OR = 0.8, 95% CI 0.6-0.9) and more likely to have impacts on eating (OR = 1.9, 95% CI 1.4-2.7) and tooth cleaning (OR = 1.6, 95

  17. Accuracy of impressions obtained with dual-arch trays.

    PubMed

    Wöstmann, Bernd; Rehmann, Peter; Balkenhol, Markus

    2009-01-01

    This study aimed to analyze the accuracy resulting from dual-arch impressions when compared to conventional impressions in complex preparations (ie, inlay and partial crown). One hundred eighty impressions were made using two different dual-arch trays; conventional trays served as the control. The accuracy of the dies obtained (Fuji-Rock EP, GC Europe) was assessed indirectly from the change of 59 transversal dimensions. Statistical analysis (t test, analysis of variance) revealed that less rigid dual-arch trays performed better than rigid ones. Though the inlay preparation was more difficult to reproduce with dual-arch trays, it can be concluded that the accuracy obtainable with nonrigid dual-arch trays is comparable to impressions taken from full-arch trays.

  18. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    SciTech Connect

    Myers, C. E.; Yamada, M.; Ji, H.; Yoo, J.; Jara-Almonte, J.; Fox, W.

    2016-11-04

    Here, the loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be applied to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruption. The verification of magnetic force balance also confirms the low-beta assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical expectations. These two co

  19. Oynophagia in patients after dental extraction: surface electromyography study.

    PubMed

    Vaiman, Michael; Nahlieli, Oded; Eliav, Eli

    2006-10-17

    Surface electromyographic (sEMG) studies were performed on 40 adult patients following extraction of lower third and second molars to research the approach and limitations of sEMG evaluation of their odynophagia complaints. Parameters evaluated during swallowing and drinking include the timing, number of swallows per 100 cc of water, and range (amplitude) of EMG activity of m. masseter, infrahyoid and submental-submandibular group. The above mentioned variables (mean + standard deviation) were measured for the group of dental patients (n = 40) and control group of healthy adults (n = 40). The duration of swallows and drinking in all tests showed increase in dental patients' group, in which this tendency is statistically significant. There was no statistically significant difference between male and female adults' duration and amplitude of muscle activity during continuous drinking in both groups (p = 0.05). The mean of electric activity (in muV) of m. masseter was significantly lower in the dental patients' group in comparison with control group. The electric activity of submental-submandimular and infrahyoid muscle groups was the same in both groups. Surface EMG of swallowing is a simple and reliable noninvasive method for evaluation of odynophagia/dysphagia complaints following dental extraction with low level of discomfort of the examination. The surface EMG studies prove that dysphagia following dental extraction and molar surgery has oral origin, does not affect pharingeal segment and submental-submandibular muscle group. This type of dysphagia has clear EMG signs: increased duration of single swallow, longer drinking time, low range of electric activity of m. masseter, normal range of activity of submental-submandibular muscle group, and the "dry swalow" aftereffect. The data can be used for evaluation of complaints and symptoms, as well as for comparison purposes in pre- and postoperative stages and in EMG monitoring during treatment of post-surgical oral

  20. Dental and skeletal relationships to attritional occlusion.

    PubMed

    Fishman, L S

    1976-01-01

    Dental attrition has been investigated in depth. Besides alterations in arch length due to attrition, skeletal and intra-arch differences were discovered. It is felt that these findings do have value in helping us realize that present-day concepts of proper occlusion cannot necessarily be applied to dentitions that existed at another time. A more thorough knowledge of occlusions exhibiting dental attrition provides information that is helpful in understanding more fully the nature of tooth eruption and associated dental arch occlusion and the interrelationships of these factors with supporting skeletal structures.

  1. Key techniques and risk management for the application of the Pile-Beam-Arch (PBA) excavation method: a case study of the Zhongjie subway station.

    PubMed

    Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

    2014-01-01

    The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area.

  2. A retrospective study of traumatic dental injuries in a Brazilian dental urgency service.

    PubMed

    Guedes, Orlando Aguirre; de Alencar, Ana Helena Gonçalves; Lopes, Lawrence Gonzaga; Pécora, Jesus Djalma; Estrela, Carlos

    2010-01-01

    Epidemiologic aspects of traumatic dental injuries (TDI) were evaluated in the permanent dentition in a sample of 847 patients treated at the Dental Urgency Service of the Dental School of the Federal University of Goiás, Brazil, between May 2000 and May 2008. The statistical treatment analyzed data from frequency distribution and chi-square test. The level of significance was set at 5% for all analyses. The results showed a higher incident among males (610; 72.01%) with mean age of 6-10 year-old. Uncomplicated crown fracture (without pulp exposure) (502; 26.95%), avulsion (341; 18.30%) and complicated crown fracture (with pulp exposure) (330; 17.71%) were the most prevalent TDI. The prevalence of trauma throughout the years showed proportionality, being observed a larger number of cases between July and September (249; 29.39%). The most affected teeth were the maxillary central incisors (65.65%), followed by the maxillary left lateral incisors (19.67%). In 311 participants (18.25%), only one tooth was involved, while in most patients (536; 81.75%), TDI occurred in more than one tooth. Significant proportion (82.27%) of traumatized teeth presented completely formed root apex. The main etiologic factors involved in TDI were falls (51.71%), traffic accidents (22.90%) and violence (5.67%). Based on the obtained data, it may be concluded that accurate policies of TDI prevention must be established, capable of stimulating the exposure of appropriate protocols for management of these lesions. The prevalence of TDI in Goiânia subpopulation is compared to the prevalence reported in epidemiological studies in others populations.

  3. Prospective Study of Dental Intervention for Hematopoietic Malignancy

    PubMed Central

    Tsuji, K.; Akashi, M.; Furudoi, S.; Yakushijin, K.; Kawamoto, S.; Okamura, A.; Matsuoka, H.; Komori, T.

    2015-01-01

    Various chemotherapeutic agents used in patients with hematopoietic malignancy cause serious side effects, including myelosuppression and immunosuppression. Immunosuppression makes patients more susceptible to infection, resulting in an increased risk of infectious complications, including the development of severe septicemia that may be life-threatening. It is necessary for dental staff to be familiar with an appropriate protocol in such cases and to share information about the chemotherapy with a hematologist. To verify the effectiveness of our dental intervention protocol, we conducted a prospective study on the incidence of complications for each myelosuppressive grade of chemotherapy in patients with hematopoietic malignancy. We compared the incidence of complications between treatment P (patients who finished all the dental treatments according to the protocol) and treatment Q (patients who did not) per grade (A, B, C, D) and incidence of systemic or oral findings. We also compared the incidence of oral complication related to the residual teeth between first chemo (patients who were undergoing chemotherapy for the first time) and prior chemo (not the first time). There were significant differences in inflammatory complications between treatment P and treatment Q. We found that both systemic and oral inflammatory complications increased with higher-grade myelosuppressive chemotherapy. Additionally, there was a significant difference between the incidence of oral complications related to the residual teeth between first chemo and prior chemo. Complete implementation of the dental intervention protocol was associated with fewer oral and systemic infectious and inflammatory complications in patients with hematopoietic malignancies undergoing chemotherapy. The incidence of oral and systemic complications also increased with grade of chemotherapy. These results support the validity of our dental intervention protocol. We should pay close attention to the oral

  4. Alignment of a buccally displaced maxillary canine in the late mixed dentition with a modified utility arch: a patient report.

    PubMed

    Leonardi, Rosalia; Licciardello, Valeria; Greco, Mariagrazia; Rossetti, Bruno; Barbato, Ersilia

    2010-01-01

    Maxillary canines and first molars are the most common ectopic teeth in young people. Ectopic buccal eruption of maxillary canines is strongly associated with lack of space or crowding in the dental arch. This report demonstrates the management of a buccally erupted maxillary canine in an 11-year, 8-month-old boy without sufficient space. The patient had a mostly dental Class II occlusion and was in the late mixed dentition, and the root development of his canines was consistent with his dental age. To correct the distal occlusion and gain space in the maxillary arch for the eruption of both canines, the patient received cervical headgear. To guide the maxillary left canine into occlusion, it was surgically exposed and a modified utility arch inserted. The result of this approach proves that a custom-designed utility arch allows the distal movement of a buccally displaced canine, while at the same time increasing the maxillary arch length.

  5. [Relationship between aortic arch shape and blood pressure response after coarctation repair].

    PubMed

    Ou, P; Mousseaux, E; Auriacombe, L; Pédroni, E; Balleux, F; Sidi, D; Bonnet, D

    2005-01-01

    The mechanisms of secondary hypertension after repair of coarctation of the aorta are not well understood. Abnormalities of the architecture of the aortic arch and their consequences on blood pressure have not been studied. In order to study the relationship between abnormalities or aortic arch architecture and resting blood pressure ninety-four patients without re-coarctation were followed up prospectively from 1997 to 2004 (mean age 16.9 +/- 8.1 years; mean weight 57.5 +/- 18.3 Kg; interval since surgery 16.3 +/- 5.4 years). All underwent MRI angiography of the thoracic aorta which enabled the abnormalities to be classified in 3 groups: gothic arch, crenellated arch and roman arch. Twenty-four patients (25.5%) were hypertensive and 70 (74.4%) normotensive. There were 40 gothic arches (42.5%). 14 crenellated arches (15%) and 40 roman arches (42.5%). Gothic arches were more commonly observed in the hypertensive patients (18/40, [45%, 95% CI 31-62]) than the crenellated arches (4/14, [28.5%, 95% CI 7-48]) or the roman arches (2/40, [5%, 95% CI 2-12]). Only the gothic arch was independently correlated with hypertension on multivariate analysis. The authors conclude that gothic deformation of the aortic arch is an independent predictive factor of hypertension in patients operated for coarctation with an excellent result on the isthmic region. Patients with a gothic appearance of their aortic arch should be followed up closely.

  6. Arched gonadal arteries in the South African negro.

    PubMed Central

    Grine, F E; Kramer, B

    1981-01-01

    The frequency with which the gonadal arteries follow a recurrent course, upwards and arching over the renal veins before descending to the gonads, is recorded for the South African Negro. The gonadal arteries follow such a course on the left side in 17, 2% and on the right side in 22% of cases. This incidence for arched left sided arteries is comparable to that recorded in other studies, but the frequency for arched right sided arteries in the South African Negro appears to be higher. Recognition of arching gonadal arteries is of importance to the vascular surgeon and urologist. PMID:7298490

  7. Comparison of overjet among 3 arch types in normal occlusion.

    PubMed

    Kim, Byung-In; Bayome, Mohamed; Kim, Yoonji; Baek, Seung-Hak; Han, Seong Ho; Kim, Seong-Hun; Kook, Yoon-Ah

    2011-03-01

    The purposes of this study were to examine the amounts of overjet in the anterior and posterior segments of 3 arch forms by using facial axis points on 3-dimensional virtual models and to verify the minimum posterior extension required for classification of the arch form in normal occlusions. Facial axis points were digitized on 97 virtual models with normal occlusion, classified into 20 tapered, 25 ovoid, and 52 square arch forms. Intercanine and intermolar arch widths and depths were measured. The best-fitting curves were created, and overjet was measured at each facial axis point. Two-way analysis of variance (ANOVA) was performed to assess the relationship between arch form and overjet in different areas. The minimum posterior extension to determine arch type was analyzed with the chi-square test. Subjects with a tapered arch form had larger overjet compared with those with ovoid and square forms, except at the central incisor. A significant difference in overjet among different areas was found in subjects with a square arch form (P <0.0001). No significant difference (P = 0.864) was found among the first and second premolar and the first molar groups for classifying arch-form types. A significant difference was found in anterior and posterior overjet according to arch types. The extension to the first premolar was sufficient to classify arch form type. It might be beneficial to consider more coordinated preformed superelastic archwires according to variations in overjet of different arch types. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  8. Follow-Up Study of 1993 Dental Hygiene Graduates. Volume XXII, Number 17, June 1994.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In an effort to evaluate the effectiveness of its dental hygiene program, William Rainey Harper College (WRHC), in Palatine, Illinois, conducted a follow-up study of its dental hygiene students. The survey instrument was mailed to all 31 1993 dental hygiene associate degree graduates, and a response rate of 97% (n=30) was attained. Results of the…

  9. Dental Hygienists' Perceptions of Preparedness for Clinical Practice: A Phenomenological Study

    ERIC Educational Resources Information Center

    Cantrell, Lezlie M.

    2012-01-01

    The purpose of this phenomenological study was to identify, compile, and describe how community college graduate dental hygienists perceived their initial dental hygiene curriculum preparation and how they subsequently adapted their curriculum preparation in order to perform their responsibilities in their first clinical dental hygiene job.…

  10. The Diversity Dilemma: A National Study of Minorities in Dental Hygiene Programs

    ERIC Educational Resources Information Center

    Moore, Tracye A.

    2012-01-01

    Given the predicted shortages of minority dental healthcare providers in the United States and the expanding diversity of the general population, it is important to recruit and retain an ethnically and culturally diverse allied dental workforce. The objectives of this study were to explore why the profession of dental hygiene exhibits minimal…

  11. The Diversity Dilemma: A National Study of Minorities in Dental Hygiene Programs

    ERIC Educational Resources Information Center

    Moore, Tracye A.

    2012-01-01

    Given the predicted shortages of minority dental healthcare providers in the United States and the expanding diversity of the general population, it is important to recruit and retain an ethnically and culturally diverse allied dental workforce. The objectives of this study were to explore why the profession of dental hygiene exhibits minimal…

  12. Dental Hygienists' Perceptions of Preparedness for Clinical Practice: A Phenomenological Study

    ERIC Educational Resources Information Center

    Cantrell, Lezlie M.

    2012-01-01

    The purpose of this phenomenological study was to identify, compile, and describe how community college graduate dental hygienists perceived their initial dental hygiene curriculum preparation and how they subsequently adapted their curriculum preparation in order to perform their responsibilities in their first clinical dental hygiene job.…

  13. Immediate versus conventional loading for the maxilla with implants placed into fresh and healed extraction sites to support a full-arch fixed prosthesis: nonrandomized controlled clinical study.

    PubMed

    Peñarrocha-Oltra, David; Covani, Ugo; Aparicio, Arnau; Ata-Ali, Javier; Peñarrocha-Diago, Miguel; Peñarrocha-Diago, Maria

    2013-01-01

    To compare immediate and conventional loading of fixed full-arch maxillary prostheses supported by implants placed in healed and fresh postextraction sites. This prospective, controlled, nonrandomized 12-month study included 30 consecutive patients requiring fixed full-arch maxillary prostheses supported by implants placed in healed and fresh extraction sites. Fifteen patients were treated with conventional loading (control group), and 15 were treated with immediate loading (test group). Each patient received six to eight implants; implants with insertion torque < 35 Ncm were conventionally loaded and excluded from the analysis. Implant success, biologic and prosthetic complications, success of the immediately loaded provisional prostheses, and marginal bone loss were assessed and analyzed statistically. One test group patient failed to attend recall visits and was excluded from the study, and 16 implants did not achieve insertion torque of 35 Ncm and were excluded from analyses. The final sample included 29 patients and 193 implants (94 test implants, 99 control implants). Implant success rates were 96.8% (test) and 99.0% (control). In the test group, the most common complications were screw loosening and tooth fractures; in the control group, dentures caused discomfort and soft tissue irritation. The success rate of the immediately loaded prostheses was 100%. Average bone loss was 0.61 ± 0.21 mm for test implants and 0.53 ± 0.18 mm for control implants. Differences between loading protocols were not statistically significant. No significant differences in implant success and peri-implant marginal bone loss were seen in the current 12-month comparison of immediate and conventional loading of maxillary fixed full-arch prostheses. Biologic and prosthetic complications were rare with both loading protocols, and all immediately loaded provisional fixed prostheses performed successfully.

  14. Hypnosis and dental anesthesia in children: a prospective controlled study.

    PubMed

    Huet, Adeline; Lucas-Polomeni, Marie-Madeleine; Robert, Jean-Claude; Sixou, Jean-Louis; Wodey, Eric

    2011-01-01

    The authors of this prospective study initially hypothesized that hypnosis would lower the anxiety and pain associated with dental anesthesia. Thirty children aged 5 to 12 were randomly assigned to 2 groups receiving hypnosis (H) or not (NH) at the time of anesthesia. Anxiety was assessed at inclusion in the study, initial consultation, installation in the dentist's chair, and at the time of anesthesia using the modified Yale preoperative anxiety scale (mYPAS). Following anesthesia, a visual analogue scale (VAS) and a modified objective pain score (mOPS) were used to assess the pain experienced. The median mYPAS and mOPS scores were significantly lower in the H group than in the NH group. Significantly more children in the H group had no or mild pain. This study suggests that hypnosis may be effective in reducing anxiety and pain in children receiving dental anesthesia.

  15. Italian multicenter study on infection hazards during dental practice: Control of environmental microbial contamination in public dental surgeries

    PubMed Central

    Castiglia, Paolo; Liguori, Giorgio; Montagna, Maria Teresa; Napoli, Christian; Pasquarella, Cesira; Bergomi, Margherita; Fabiani, Leila; Monarca, Silvano; Petti, Stefano

    2008-01-01

    Background The present study assessed microbial contamination in Italian dental surgeries. Methods An evaluation of water, air and surface microbial contamination in 102 dental units was carried out in eight Italian cities. Results The findings showed water microbial contamination in all the dental surgeries; the proportion of water samples with microbial levels above those recommended decreased during working. With regard to Legionella spp., the proportion of positive samples was 33.3%. During work activity, the index of microbial air contamination (IMA) increased. The level of microbial accumulation on examined surfaces did not change over time. Conclusion These findings confirm that some Italian dental surgeries show high biocontamination, as in other European Countries, which highlights the risk of occupational exposure and the need to apply effective measures to reduce microbial loads. PMID:18644099

  16. Cost as a barrier to accessing dental care: findings from a Canadian population-based study.

    PubMed

    Thompson, Brandy; Cooney, Peter; Lawrence, Herenia; Ravaghi, Vahid; Quiñonez, Carlos

    2014-01-01

    The aim of this study is to determine the demographic and socioeconomic characteristics of Canadians who report cost barriers to dental care. An analysis of data collected from the 2007/09 Canadian Health Measures Survey was undertaken from a sample of 5,586 Canadian participants aged 6-79. Cost barriers to dental care were operationalized through two questions: "In the past 12 months, have you avoided going to a dental professional because of the cost of dental care?" and "In the past 12 months, have you avoided having all the dental treatment that was recommended because of the cost?" Logistic regressions were conducted to identify relationships between covariates and positive responses to these questions. Approximately 17.3 percent of respondents had avoided a dental professional because of cost within the previous year, and 16.5 percent had declined recommended dental treatment because of cost. Adjusted estimates demonstrate that respondents with lower incomes and without dental insurance were over four times more likely to avoid a dental professional because of cost and approximately two and a half times more likely to decline recommended dental treatment because of cost. Nearly one out of five Canadians surveyed reported cost barriers to dental care. This study provides valuable baseline information for future studies to assess whether financial barriers to dental care are getting better or worse for Canadians. © 2014 American Association of Public Health Dentistry.

  17. Arch width changes in patients with Class II division 1 malocclusion treated with maxillary first premolar extraction and non-extraction method.

    PubMed

    Shirazi, Sajjad; Kachoei, Mojgan; Shahvaghar-Asl, Naiemeh; Shirazi, Samaneh; Sharghi, Reza

    2016-10-01

    The aim of this study was to determine arch width changes during maxillary first premolars extraction and non-extraction treatment in patients with Class II division 1 malocclusion. Dental casts of 91 Class II division 1 patients (36 males and 55 females) were evaluated. The minimum age of the subjects at the beginning of treatment was above 16 years. 48 patients were treated with extraction of the maxillary first premolars and 43 patients were treated without extraction. Pre- and post-treatment maxillary and mandibular inter-canine and inter-molar arch widths were measured. At the end of treatment, maxillary and mandibular inter-canine widths of both groups increased significantly. The maxillary inter-molar width decreased in the extraction group and increased in the non-extraction group. The mandibular inter-molar width increased significantly in both groups. No significant differences were observed between males and females. The results of this study indicated that there was a tendency for an increase in arch width during both the extraction and non-extraction treatment except maxillary inter-molar width in the extraction cases. Key words:Dental arch, malocclusion, angle Class II, tooth movement, extraction.

  18. Arch width changes in patients with Class II division 1 malocclusion treated with maxillary first premolar extraction and non-extraction method

    PubMed Central

    Shirazi, Sajjad; Kachoei, Mojgan; Shahvaghar-Asl, Naiemeh; Shirazi, Samaneh

    2016-01-01

    Background The aim of this study was to determine arch width changes during maxillary first premolars extraction and non-extraction treatment in patients with Class II division 1 malocclusion. Material and Methods Dental casts of 91 Class II division 1 patients (36 males and 55 females) were evaluated. The minimum age of the subjects at the beginning of treatment was above 16 years. 48 patients were treated with extraction of the maxillary first premolars and 43 patients were treated without extraction. Pre- and post-treatment maxillary and mandibular inter-canine and inter-molar arch widths were measured. Results At the end of treatment, maxillary and mandibular inter-canine widths of both groups increased significantly. The maxillary inter-molar width decreased in the extraction group and increased in the non-extraction group. The mandibular inter-molar width increased significantly in both groups. No significant differences were observed between males and females. Conclusions The results of this study indicated that there was a tendency for an increase in arch width during both the extraction and non-extraction treatment except maxillary inter-molar width in the extraction cases. Key words:Dental arch, malocclusion, angle Class II, tooth movement, extraction. PMID:27703608

  19. Decontamination Methods Used for Dental Burs – A Comparative Study

    PubMed Central

    Hugar, Deepa; Hugar, Santosh; Ranjan, Shashi; Kadani, Megha

    2014-01-01

    Aims and Objectives: Infection control and modes of sterilizations are the key factors to avoid cross transmission of infection in the field of dentistry. Transmission of disease or infection is noted with improper sterilization of reused instruments. Dental burs are the most important tool in any endodontic or conservative procedures of teeth involving tooth contouring, restorative filling procedures and endodontic procedures. Hence, the present study is undertaken to assess the efficacy of different methods of sterilization or decontamination which are routinely used in dental clinics. Materials and Methods: For the present study 96 round diamond burs were selected and divided into 6 groups. These burs were used for the access cavity preparation to get contamination and subjected for bacteriological culture. After getting base line date burs were subjected to manual scrubbing, hot air oven, glass bead sterilizer, ultrasonic cleaner and autoclave to get post decontamination data. Results: The study revealed that mean colony forming units/ml of Streptococcus mutans decreased maximum for autoclave with 80% reduction, for Lactobacilli 76% reduction and for Candida albicans maximum reduction seen for glass bead sterilizer with 74%. Conclusion: Findings of our study revealed that none of the methods used were found to be absolutely efficacious in the decontamination of dental burs. However, among the experimental groups used in the present study, autoclave was found to be the relatively best method. PMID:25121062

  20. Incremental dental development: methods and applications in hominoid evolutionary studies.

    PubMed

    Smith, Tanya M

    2008-02-01

    This survey of dental microstructure studies reviews recent methods used to quantify developmental variables (daily secretion rate, periodicity of long-period lines, extension rate, formation time) and applications to the study of hominoid evolution. While requisite preparative and analytical methods are time consuming, benefits include more precise identification of tooth crown initiation and completion than conventional radiographic approaches. Furthermore, incremental features facilitate highly accurate estimates of the speed and duration of crown and root formation, stress experienced during development (including birth), and age at death. These approaches have provided insight into fossil hominin and Miocene hominoid life histories, and have also been applied to ontogenetic and taxonomic studies of fossil apes and humans. It is shown here that, due to the rapidly evolving nature of dental microstructure studies, numerous methods have been applied over the past few decades to characterize the rate and duration of dental development. Yet, it is often unclear whether data derived from different methods are comparable or which methods are the most accurate. Areas for future research are identified, including the need for validation and standardization of certain methods, and new methods for integrating nondestructive structural and developmental studies are highlighted.

  1. Restructuring an undergraduate dental curriculum to global standards--a case study in an Indian dental school.

    PubMed

    Kadagad, P; Tekian, A; Pinto, P X; Jirge, V L

    2012-05-01

    Globalisation has affected all aspects of life and dentistry is no exception. In the context of today's dentist being a global citizen, undergraduate training in dentistry is set to ensure converging standards so that international recognition of dental qualifications can move forward. The decision of the Dental Council of India to expand the undergraduate dental program to five years provides an opportunity to be part of the endeavor of the Global Dental Congress to achieve converging standards which was initially for the European Union, and now spreading out globally. Economic emergence in Indian subcontinent has resulted in growing oral health care needs both in quality and quantity. To address this issue, the graduating dentist needs to be trained following a competency based curricular model. Access to Internet facilitated the goal of achieving converging standards of dental schools to be feasible because of the instant communication and capacity to share information about training strategies via technology across the globe. Upgrading the undergraduate training to global standards by dental schools in India could be a wise and strategic move both for attracting students to study in India, as well as retaining the graduates after their training. The following is a case study of an Indian dental school set to restructure the undergraduate curriculum to global standards using the 8 steps of Kotter's transformational change. Change in curriculum and the subsequent accreditation of the school in global platform not only attracts prospective students but also results in producing competent dentists. Dental education provided by the institution can result in quality assurance, benchmarking the assessment system to achieve international recognition. This paper highlights the need and importance of facilitation of international convergence with long term aspirations for mutual recognition of international degrees. © 2011 John Wiley & Sons A/S.

  2. Active Residents in Care Homes (ARCH): study protocol to investigate the implementation and outcomes of a whole-systems activity programme in residential care homes for older people.

    PubMed

    Koskela, Sian A; Jones, Fiona; Clarke, Natasha; Anderson, Liezl; Kennedy, Bernadette; Grant, Robert; Gage, Heather; Hurley, Michael V

    2017-03-01

    To evaluate the effectiveness, acceptability and costs of Active Residents in Care Homes, ARCH - a programme aiming to increase opportunities for activity in older care home residents. Feasibility study. Residential care homes for older people. 10-15 residents, staff and family members will be recruited in each of the three participating care homes. ARCH is a 12-month 'whole-systems' programme implemented by occupational therapists and physiotherapists. They will conduct a comprehensive assessment of each care home, considering the physical environment, working practices and organisation structure as well as residents' individual needs, and recommend ways to address barriers and increase residents' activity levels. The therapists will then work with staff to improve understanding of the issues, instigate training, environmental, organisational and working practice changes as necessary. Residents' activity levels, health and quality of life will be tested using several measures to see which are practicable and appropriate for this population in this context. This includes: Assessment of Physical Activity in Frail Older People; Pool Activity Level Checklist; Dementia Care Mapping observations; and EQ-5D-5L. Residents will be assessed prior to programme implementation then 4- and 12-months post-implementation. Semi-structured interviews will explore the experiences of residents, staff, family members and therapists. Providing evidence of effectiveness and acceptability of ARCH, and documenting factors that impede/facilitate implementation will help us identify ways to enhance the care and quality of life of older people in residential care, and our understanding of how to implement them. ISRCTN24000891. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

  3. Biomechanical aspects of segmented arch mechanics combined with power arm for controlled anterior tooth movement: A three-dimensional finite element study.

    PubMed

    Ozaki, Hiroya; Tominaga, Jun-Ya; Hamanaka, Ryo; Sumi, Mayumi; Chiang, Pao-Chang; Tanaka, Motohiro; Koga, Yoshiyuki; Yoshida, Noriaki

    2015-01-01

    The porpose of this study was to determine the optimal length of power arms for achieving controlled anterior tooth movement in segmented arch mechanics combined with power arm. A three-dimensional finite element method was applied for the simulation of en masse anterior tooth retraction in segmented power arm mechanics. The type of tooth movement, namely, the location of center of rotation of the maxillary central incisor in association with power arm length, was calculated after the retraction force was applied. When a 0.017 × 0.022-in archwire was inserted into the 0.018-in slot bracket, bodily movement was obtained at 9.1 mm length of power arm, namely, at the level of 1.8 mm above the center of resistance. In case a 0.018 × 0.025-in full-size archwire was used, bodily movement of the tooth was produced at the power arm length of 7.0 mm, namely, at the level of 0.3 mm below the center of resistance. Segmented arch mechanics required shorter length of power arms for achieving any type of controlled anterior tooth movement as compared to sliding mechanics. Therefore, this space closing mechanics could be widely applied even for the patients whose gingivobuccal fold is shallow. The segmented arch mechanics combined with power arm could provide higher amount of moment-to-force ratio sufficient for controlled anterior tooth movement without generating friction, and vertical forces when applying retraction force parallel to the occlusal plane. It is, therefore, considered that the segmented power arm mechanics has a simple appliance design and allows more efficient and controllable tooth movement.

  4. One-stage hybrid procedure without sternotomy for treating thoracic aortic pathologies that involve distal aortic arch: a single-center preliminary study

    PubMed Central

    Ren, Changwei; Guo, Xi; Sun, Lizhong; Huang, Lianjun; Lai, Yongqiang

    2015-01-01

    Objective This study aims to evaluate the initial results of a hybrid procedure without sternotomy for treating descending thoracic aortic disease that involves distal aortic arch. It also intends to report our initial experience in performing this procedure. Methods A total of 45 patients (35 males and 10 females) with descending thoracic aortic disease underwent a hybrid procedure, namely, thoracic endovascular aortic repair (TEVAR) combined with supra-arch branch vessel bypass, in our center from April 2009 to August 2014. Right axillary artery to left axillary artery bypass (n=20) or right axillary artery to left common carotid artery (LCCA) and left axillary artery bypass (n=25) were performed. The conditions of all patients were followed up from the 2nd month to the 65th month postoperative (mean, 26.0±17.1). Mortality within 30 days, complications such as endoleak after the hybrid procedure, and stenosis or blockage of the bypass graft during the follow-up period was assessed. Results All the patients underwent a one-stage procedure. One case of death and one case of cerebral infarction were reported within 30 days. One patient died of the sudden drop in blood pressure during the 2nd day of operation. Meanwhile, another patient suffered from cerebral infarction. Two patients underwent open surgery, and one of them had to undergo a second TEVAR during the follow-up period. Moreover, endoleak occurred in two patients and a newly formed intimal tear was observed in one patient. Overall, 93.2% of the patients survived without any complication related to the hybrid procedure. Conclusions Initial results suggest that the one-stage hybrid procedure is a suitable therapeutic option for thoracic aortic pathologies that involve distal aortic arch. However, this procedure is not recommended for type-B aortic dissection, in which a tear is located in the greater curvature or near the left subclavian artery (LSA), because of the high possibility of endoleak occurrence

  5. Spectroscopic study of demineralization and restoration processes in dental enamel

    NASA Astrophysics Data System (ADS)

    Sokolova, Tatiana N.; Surmenko, Elena L.; Tuchin, Valery V.; Kishen, A.; Chebotarevsky, Yu. V.

    2007-07-01

    The spectroscopic study of dental enamel by LIBS (laser induced breakdown spectroscopy), FTIR (Fourier transform infrared) and XRD (X-ray diffraction) are represented. The changes of enamel structure and composition in process of natural (caries) and artificial demineralization and restoration were studied. In comparison of sound and carious enamel LIBS showed a decrease of the content of Ca, P and change of the content of some other macro-and trace elements (Mn, Na, Fe, Zn etc). The character of the elemental composition variation was stipulated by the concrete disease. Analysis of FTIR and XRD spectra of dental samples, subjected to artificial demineralization and restoration, showed that restoration action reveals slower, than demineralization. And in some cases the damage of crystals after restoration is more significant than after demineralization.

  6. Immediate loading with fixed full-arch prostheses in the maxilla: Review of the literature

    PubMed Central

    Peñarrocha-Oltra, David; Covani, Ugo; Peñarrocha-Diago, Miguel

    2014-01-01

    Objectives: To critically review the evidence-based literature on immediate loading of implants with fixed full-arch prostheses in the maxilla to determine 1) currently recommended performance criteria and 2) the outcomes that can be expected with this procedure. Study Desing: Studies from 2001 to 2011 on immediate loading with fixed full-arch maxillary prostheses were reviewed. Clinical series with at least 5 patients and 12 months of follow-up were included. Case reports, studies with missing data and repeatedly published studies were excluded. In each study the following was assessed: type of study, implant type, number of patients, number of implants, number of implants per patient, use of post-extraction implants, minimum implant length and diameter, type of prosthesis, time until loading, implant survival rate, prosthesis survival rate, marginal bone loss, complications andmean follow-up time. Criteria for patient selection, implant primary stability and bone regeneration were also studied. Results: Thirteen studies were included, reporting a total of 2484 immediately loaded implants in 365 patients. Currently accepted performance criteria regarding patient and implant selection, and surgical and prosthetic procedures were deduced from the reviewed articles. Implant survival rates went from 87.5% to 100%, prosthesis survival rates from 93.8% to 100% and radiographic marginal bone loss from 0.8 mm to 1.6 mm.No intraoperative complications and only minor prosthetic complications were reported. Conclusions: The literature on immediate loading with fixed full-arch prostheses in the maxilla shows that a successful outcome can be expected if adequate criteria are used to evaluate the patient, choose the implant and perform the surgical and prosthetic treatment. Lack of homogeneity within studies limits the relevance of the conclusions that can be drawn, and more controlled randomized studies are necessary to enable comparison between the immediate and the

  7. Electrophoretic analysis of whole saliva and prevalence of dental caries. A study in Mexican dental students.

    PubMed

    Banderas-Tarabay, José Antonio; Zacarías-D'Oleire, Ivonne Gardenia; Garduño-Estrada, Ricardo; Aceves-Luna, Enrique; González-Begné, Mireya

    2002-01-01

    Variability in salivary proteins and their posttranslational modifications may play an important role in determining their protective features against dental caries. Knowledge of molecular content of saliva in different populations is important for a better understanding of protective properties of this biological fluid. Aims of this study were to analyze electrophoretic pattern and protein composition in resting human whole saliva (HWS) of a Mexican population and to correlate these data with decayed, missing, and filled teeth (DMFT) index in these subjects. Resting human whole saliva samples were collected from 120 healthy Mexican dental students. Salivary flow rate, protein concentration, and electrophoretic profile analyzed qualitatively by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were correlated with DMFT index. Gels were successively triple-stained with Coomassie brilliant blue R250, periodic acid Schiff (PAS), silver stain, and salivary molecules were scored as absent (-), present (+/-), and high intensity and size (+). These showed no substantial differences in number of bands between males and females; however, a slight correlation between total protein concentration and sex was found (p study concludes that genetic phenotypic polymorphism is present in the population studied and has correlations with oral health. We found specific characteristics and individual variability in number, intensity, and apparent molecular weight of band features in this Mexican population. These studies provide the initial step for creating an HWS database in this population.

  8. Awareness of forensic odontology among dental practitioners in Chennai: A knowledge, attitude, practice study

    PubMed Central

    Preethi, S; Einstein, A; Sivapathasundharam, B

    2011-01-01

    Objective: The aim of the study is to analyze the knowledge, attitude and practice of forensic odontology among dental practitioners in Chennai. Materials and Methods: A cross-sectional study was conducted in a sample of 322 dental practitioners in Chennai and data was collected by means of a questionnaire. Results: Twenty-one percent of the dental practitioners did not maintain dental records in their clinic/workplace, with only 12% of the practitioners maintaining complete records. Ninety-three percent of dental practitioners were not maintaining dental records for more than seven years. The significance of ante-mortem records in identifying deceased suspects was not known to 17% of the dental practitioners. Forty percent of the dental practitioners were not aware of child abuse and the actions to be taken. Dental age estimation was not known to 41% of the dental practitioners. Thirty-eight percent of the practitioners were unaware of the accurate method of individual identification. About 18% of the dental practitioners did not know the significance of bite mark patterns of the teeth. Ninety-three percent of the practitioners lacked formal training in collecting, evaluating and presenting dental evidence. Thirty percent of dental practitioners did not know they can testify as an expert witness in the court of law. Forty percent of the dental practitioners were unaware of identifying the age and gender of an individual in mass disasters. Conclusion: Our study revealed inadequate knowledge, poor attitude and lack of practice of forensic odontology prevailing among the dental practitioners in Chennai. PMID:22408322

  9. [Dental caries and early childhood development: a pilot study].

    PubMed

    Núñez, F Loreto; Sanz, B Javier; Mejía, L Gloria

    2015-01-01

    To investigate the association between dental caries and early childhood development in 3-year-olds from Talca, Chile. A pilot study with a convenience sample of 3-year-olds from Talca (n = 39) who attend public healthcare centers. Child development was measured by the Psychomotor Development Index (PDI), a screening tool used nationally among pre-school children to assess language development, fine motor skills and coordination areas. Dental caries prevalence was evaluated by decayed, missing, filled teeth (DFMT) and decayed, missing, filled tooth surfaces (DFMS) ceo-d and ceo-s indexes. The children were divided into two groups according to the PDIscore: those with a score of 40 or more were considered developmentally normal (n = 32), and those with a score below 40 were considered as having impaired development (n = 7). The severity of caries (DMFT) was negatively correlated with PDI (r = -0.82), and children with the lowest TEPSI score had the highest DFMT values. The average DMFT in children with normal development was 1.31, and 3.57 for those with impaired development. This pilot study indicates that the severity of dental caries is correlated with early childhood development. Copyright © 2015. Publicado por Elsevier España, S.L.U.

  10. Radiographic study of delayed tooth development in patients with dental agenesis.

    PubMed

    Ruiz-Mealin, Erika V; Parekh, Susan; Jones, Steven P; Moles, David R; Gill, Daljit S

    2012-03-01

    The aims of this study were to compare the radiographic development of permanent teeth in a group of children affected by dental agenesis with an unaffected control group and to determine the effects of confounding factors including the severity of the dental agenesis, age, sex, ethnicity, and the number of stages used to estimate dental age. A single-center retrospective cross-sectional study of dental panoramic tomographs was undertaken between July 2007 and April 2008 in a postgraduate teaching school. A total of 139 patients (aged 9-18 years) were recruited from the orthodontic clinic on the basis of predetermined inclusion and exclusion criteria to either a dental agenesis group or a control group. Dental panoramic tomograms were assessed, and the stages of development of the permanent teeth in the left maxillary and left mandibular regions were scored by using the 12 stages of Haavikko and the 8 stages of Demirjian and Goldstein. For each tooth scored, the mean dental age and standard error were determined by using the dental age assessment method, and an estimated dental age for each subject was derived by using the weighted average method. A statistically significant delay in dental age was found in the patients with dental agenesis compared with the control group. The dental age assessment method of Haavikko showed a delay of 1.20 years (SD, 1.74), and the method of Demirjian and Goldstein showed a delay of 1.64 years (SD, 1.75). It was also observed that older patients with dental agenesis had greater delays in tooth formation (P <0.001). With the Haavikko method, for every year of chronologic age, the delay in dental age increased by 0.53 year; with the Demirjian and Goldstein method, the delay increased by 0.48 year. A significant association was seen between the severity of dental agenesis and the delay in dental age (P <0.01). With both methods, for each additional developmentally absent tooth, the dental age was delayed by 0.13 year (lower confidence

  11. The Dental Hygienist: A Study of the Employment Patterns of Registered Dental Hygienists in Southern Maryland.

    ERIC Educational Resources Information Center

    Armstrong, David F.

    This document reports the results of a survey of all registered dental hygienists reported by the State of Maryland as residents of southern Maryland (n=397), 82% of whom responded. The purpose of the survey was to examine the employment patterns of dental hygienists in the Montgomery College service area in order to determine if hygienists who…

  12. [Evaluation of the timing of orthodontic arch expansion and graft in cleft lip and palate].

    PubMed

    Chang, Le; Wang, Yingnan; Liu, Hongyan

    2016-04-01

    Maxillary transverse growth is inhibited by congenital cleft, early surgical scar strain, and oppression of lipmuscles in patients with cleft lip and palate. Clinical manifestations have shown severely constricted maxilla, insufficientmaxillary width, mismatch of upper and lower dental arches, and crossbite. Alveolar bone graft and arch expansion can effectively correct the deficiency in maxillary width. This paper discusses the timing and success rate of alveolar bone graft, as wellas the relationship between alveolar bone graft and arch expansion. Secondary alveolar bone graft is optimally performed beforepermanent canine eruption, especially when the teeth have formed between half and three quarters of their roots. Rapid maxillaryexpansion prior to alveolar bone graft is beneficial because this process increases the gap of the cleft, expands bone graft, andreduces the difficulty. However, the stability of this process remains controversial. Small-scale studies have reported that rapidmaxillary expansion after alveolar bone graft can open the midpalatal suture without bone graft loss. Slow maxillary expansioncan provide continuous light forces to reconstruct the bone. However, these studies are coordinated with fixed orthodontictreatment. Further research is necessary to determine the effects of maxillary expansion on long-term stability of teeth.

  13. DENTAL MATERIALS.

    DTIC Science & Technology

    The study deals with the determination of characteristic physical and mechanical properties of restorative dental materials, and effect of...manipulative variables on these properties. From the study an entirely new dental gold inlay casting technic was developed, based on the principle of...controlled water added hygroscopic technic. The method has had successful dental applications and is a recognized method of dental inlay casting procedure

  14. Clinical Evaluation of Efficacy of CIA and CNA Intrusion Arches

    PubMed Central

    Vora, Sambhav; Pandey, Vinisha

    2015-01-01

    Background and Objectives Excessive overbite is one of the most common problems that confront the orthodontist. Deep bite can be due to infraocclusion of posterior teeth, supraocclusion of anterior teeth or a combination of the two. Correction of same can be carried out by extrusion of molars, intrusion of incisors or by a combination of both respectively. Various intrusion arches are recommended for correcting deep bite by true intrusion of anterior teeth, Utility arches, Segmental arch, Connecticut Intrusion Arch (CIA) and Connecticut New Arch (CNA). The purpose of this study was to evaluate clinical efficacy of CIA and CNA intrusion arches. Materials and Methods Tracings recorded from pre and post-treatment lateral cephalograms of 25 patients treated by CIA (Group I) and another 25 patients treated by CNA (Group II) intrusion arches in deep bite cases after four months of treatment were analysed and findings were recorded. Statistical Analysis Paired t-test was used to compare pre and post-treatment changes within Groups I and II and unpaired t-test was used to compare treatment changes between Group I and Group II. A P-value of < 0.05 was set for statistical significance. Results Findings of this study demonstrate that an average of 1mm of intrusion takes place with CIA intrusion arch and 1.3mm with CNA intrusion arch in a period of 4 months. Both intrusion arches do not affect the position of molar in vertical or anteroposterior plane. Interpretation & Conclusion Both CIA and CNA intrusion arches are effective in bringing about intrusion of lower incisors. PMID:26501008

  15. Quality of Life Among Dental Students: A Survey Study.

    PubMed

    Andre, Amanda; Pierre, Gaelle C; McAndrew, Maureen

    2017-10-01

    Quality of life is a complex construct that affects the overall life satisfaction, emotional well-being, and functioning of individuals. The aim of our study was to assess the quality of life of dental students at one U.S. dental school, using the World Health Organization Quality of Life (WHOQOL)-BREF, a multi-dimensional, cross-cultural, validated, and reliable survey instrument. Of the 1,437 students invited to participate, 401 students responded, but 17 were excluded because of missing data. The final sample consisted of 384 students for an overall response rate of 27%: response rates by year were first year 32.6%, second year 16.9%, third year 26.6%, and fourth year 24.0%. The results showed that the responding students rated their overall quality of life as good. The Physical Health domain had the highest mean score, while the Psychological domain had the lowest. Females reported higher quality of life than males in the Social Relationships domain. Single students were found to have a lower perceived quality of life than married students. Older students were found to have lower perceived quality of life in the Physical Health and Environment domains. Physical Health domain scores were significantly higher for fourth-year than first-year respondents, while Psychological domain scores were significantly lower for third-year than first-year respondents. Further research is needed to explore the effect of dental school on the quality of life of dental students. Targeted programs to impact students' quality of life at various points in the curriculum may be beneficial.

  16. The viscoelastic behavior of dental adhesives: a nanoindentation study.

    PubMed

    Sadr, Alireza; Shimada, Yasushi; Lu, Hongbing; Tagami, Junji

    2009-01-01

    In order to predict the long-term performance of dental adhesives, it is necessary to understand their mechanical properties. The objective of this study was to use a new nanoindentation technique to characterize the in-plane linear viscoelastic properties of dental adhesive layers. The dental adhesives used were Clearfil SE Bond (CSE) and Clearfil Tri-S Bond (CTS) by Kuraray Medical and Single Bond (SIB) and Single Bond Plus (SBP) by 3M ESPE. A thin film of each adhesive was made on a micro-glass slide, and was then tested on a nanoindenter system (ENT 1100, Elionix) with a Berkovich indenter at a constant loading rate of 0.1 mN/s up to a maximum load of 1.8 mN. The load-displacement data of the loading segment were fitted to a curve to find best fit parameters for a generalized Kelvin viscoelastic model, from which creep compliance and Young's modulus were calculated. The modulus results were compared to the values calculated by the nanoindentation device. The experimental data fitted well to the viscoelastic model for all materials (R>0.9999). SIB and CTS showed higher creep compliance compared to SBP and CSE. The modulus values obtained using the model were 4.0, 2.6, 2.4 and 4.2GPa for CSE, CTS, SIB and SBP, respectively. The nanoindentation default software designed for time-independent materials significantly overestimated the modulus values up to 2.5 times. As generally expected for polymer materials, the adhesives tested showed time-dependent viscoelastic behavior. The mechanical evaluation techniques developed for time-independent materials ignore this behavior and may not be appropriate for dental adhesives.

  17. Prevalence of dental caries and dental care utilization in preschool urban children enrolled in a comparative-effectiveness study

    PubMed Central

    Kopycka-Kedzierawski, D T.; Billings, R J.

    2011-01-01

    Aim To assess dental caries prevalence and dental care utilization in pre-school children enrolled in urban childcare centres that participated in a comparative-effectiveness study. Study design Cross-sectional study. Methods Caries prevalence was determined in a cohort of children 12-60 months of age. Eligible children were randomized into two groups: group one received a traditional visual/tactile oral examination and group two received a Teledentistry examination. Questionnaires were administered to the children's parents/guardians to gather demographics and information about using dental and medical services. Results Of 234 children examined, approximately 28% had caries experience. The mean dfs score was 1.56 with a range of 0 to 34 carious surfaces. The mean dfs score for the children examined by means of Teledentistry was 1.75 and for the children examined by means of the traditional visual/tactile method mean dfs was 1.40; the means between the two groups were not significantly different. Twenty-six children showed evidence of being treated for dental caries. According to the parents, 31.5% of the children had never had a dental check-up before, only 3% of the children were lacking dental insurance and majority of the parents (92%) did not perceive accessing dental care for the children as a problem. Statistics The Wilcoxon Mann-Whitney test and the Kruskal-Wallis test were used to assess statistical differences among groups of children. Conclusions The data show that 28% of the children had caries and, of these, 61% had never been treated for caries, thus indicating that continued efforts are needed to improve oral health care utilization by inner-city preschool children. PMID:21640057

  18. Reliability and Correlation of Static and Dynamic Foot Arch Measurement in a Healthy Pediatric Population.

    PubMed

    Scholz, Timo; Zech, Astrid; Wegscheider, Karl; Lezius, Susanne; Braumann, Klaus-Michael; Sehner, Susanne; Hollander, Karsten

    2017-07-14

    Measurement of the medial longitudinal foot arch in children is a controversial topic, as there are many different methods without a definite standard procedure. The purpose of this study was to 1) investigate intraday and interrater reliability regarding dynamic arch index and static arch height, 2) explore the correlation between both arch indices, and 3) examine the variation of the medial longitudinal arch at two different times of the day. Eighty-six children (mean ± SD age, 8.9 ± 1.9 years) participated in the study. Dynamic footprint data were captured with a pedobarographic platform. For static arch measurements, a specially constructed caliper was used to assess heel-to-toe length and dorsum height. A mixed model was established to determine reliability and variation. Reliability was found to be excellent for the static arch height index in sitting (intraday, 0.90; interrater, 0.80) and standing positions (0.88 and 0.85) and for the dynamic arch index (both 1.00). There was poor correlation between static and dynamic assessment of the medial longitudinal arch (standing dynamic arch index, r = -0.138; sitting dynamic arch index, r = -0.070). Static measurements were found to be significantly influenced by the time of day (P < .001), whereas the dynamic arch index was unchanged (P = .845). This study revealed some further important findings. The static arch height index is influenced by gender (P = .004), whereas dynamic arch index is influenced by side (P = .011) and body mass index (P < .001). Dynamic and static foot measurements are reliable for medial longitudinal foot arch assessment in children. The variation of static arch measurements during the day has to be kept in mind. For clinical purposes, static and dynamic arch data should be interpreted separately.

  19. Postural changes in dental hygienists. Four-year longitudinal study.

    PubMed

    Barry, R M; Woodall, W R; Mahan, J M

    1992-01-01

    Numerous surveys identify the occurrence of musculoskeletal complaints as a concern in dentistry. However, no longitudinal data exist to indicate whether postural changes occur as a result of practicing dental hygiene. The purpose of this preliminary, four-year longitudinal study was to investigate whether any postural changes developed during the hygienists' clinical education and/or during subsequent dental hygiene practice after one and/or two years. It was anticipated that the awkward positions and intense physical demands placed on hygienists might initiate musculoskeletal problems, but that no postural changes would occur over this short period of time. Nine of 10 dental hygienists in the graduating class of 1987 were surveyed for existing musculoskeletal complaints, and the subjects were photographed for a measurement of postural change. Responses from participants indicated an increase in musculoskeletal-related complaints in each of the six areas investigated. The photographic findings indicated that one of the nine hygienists showed an increase in forward head posture, a postural change.

  20. Experimental study determining the mechanical properties of dental floss holders.

    PubMed

    Wolff, Anna; Pritsch, Maria; Dörfer, Christof; Staehle, Hans Jörg

    2011-06-01

    This study determined the mechanical properties of 19 dental floss holders. Eight single-use holders and 11 reusable ones were tested. An in vitro model with dental proximal contact strength of 8 N was created. Every device had to pass the proximal contact 30 times. We measured (1) the displacement of the floss [mm], (2) the force [N] necessary to pass the proximal contact after the 30th passage, (3) the loosening of the floss (offset [mm]), and (4) the change in the distance between the branches [mm]. Each measurement was repeated seven times. The results are displacement of the floss after 30 passages, 2.0 to 9.2 mm; passage force, 2.6 to 11 N; increases in branch distance, 0-2.9 mm; offset of the floss, 0-1.8 mm (all numbers are medians). Based on cleaning a full dentition (30 passages), we suggest introducing minimal requirements of <4 mm for the displacement of the floss, ≥11 N for the force, and <0.1 mm for the difference in branch distance and the offset. Only two products fulfilled our criteria. The tests show that dental floss holders vary extremely in their mechanical properties. Their effective use seems often impossible due to limited mechanical properties.

  1. Social equality and dental conditions--a study of an adult population in Southern Sweden.

    PubMed

    Bagewitz, I C; Söderfeldt, B; Palmqvist, S; Nilner, K

    2000-01-01

    This study aimed to: describe dental conditions--focusing on prosthodontic variables--in relation to social conditions in the late 1990s in an adult population of Southern Sweden, evaluate if a change could be traced in the pattern of socioeconomic influences on dental conditions, and study if various attitudes toward dental care were associated with social as well as dental conditions. The study was based on questionnaire responses. Significant differences in dental conditions and denture prevalence were found for age and education. To a majority of the sample it was very important to have own teeth and/or fixed restorations and the opportunity to attend regular dental care. The cost for dental care was very important for 52% of the sample especially for men, those with low education, and those wearing removable denture. Need for dental care that could not be provided for because of the costs was experienced by 9%. Eighteen percent stated that they once or more had refrained from dental care because of the cost. Those with removable dentures and low education dominated. Besides socioeconomic differences in dental conditions, there were sociodental differences in attitudes concerning the importance of costs, self-estimated needs, and cost-barriers for dental care.

  2. Lateral testing of glued laminated timber tudor arch

    Treesearch

    Douglas R. Rammer; Philip Line

    2016-01-01

    Glued laminated timber Tudor arches have been in wide use in the United States since the 1930s, but detailed knowledge related to seismic design in modern U.S. building codes is lacking. FEMA P-695 (P-695) is a methodology to determine seismic performance factors for a seismic force resisting system. A limited P-695 study for glued laminated timber arch structures...

  3. Improved dynamical modelling of the Arches cluster

    NASA Astrophysics Data System (ADS)

    Lee, Joowon; Kim, Sungsoo S.

    2014-05-01

    Recently, Clarkson et al. (2012) measured the intrinsic velocity dispersion of the Arches cluster, a young and massive star cluster in the Galactic center. Using the observed velocity dispersion profile and the surface brightness profile of Espinoza et al. (2009), they estimate the cluster's present-day mass to be ˜ 1.5×104 M⊙ by fitting an isothermal King model. In this study, we trace the best-fit initial mass for the Arches cluster using the same observed data set and also the anisotropic Fokker-Planck calculations for the dynamical evolution.

  4. Prevalence of dental caries and dental care utilisation in preschool urban children enrolled in a comparative-effectiveness study.

    PubMed

    Kopycka-Kedzierawski, D T; Billings, R J

    2011-06-01

    To assess dental caries prevalence and dental care utilisation in pre-school children enrolled in urban childcare centres that participated in a comparative effectiveness study. Cross-sectional study. Caries prevalence was determined in a cohort of children 12-60 months of age. Eligible children were randomised into two groups: group one received a traditional visual/tactile oral examination and group two received a teledentistry examination. Questionnaires were administered to the children's parents/guardians to gather demographics and information about using dental and medical services. Of 234 children examined, approximately 28% had caries experience. The mean dfs score was 1.56 with a range of 0-34 carious surfaces. The mean dfs score for the children examined by means of teledentistry was 1.75 and for the children examined by means of the traditional visual/tactile method mean dfs was 1.40; the means between the two groups were not significantly different. Twenty-six children showed evidence of being treated for dental caries. According to the parents, 31.5% of the children had never had a dental check-up before, only 3% of the children were lacking dental insurance and majority of the parents (92%) did not perceive accessing dental care for the children as a problem. The Wilcoxon Mann-Whitney test and the Kruskal-Wallis test were used to assess statistical differences among groups of children. The data showed that 28% of the children had caries and, of these, 61% had never been treated for caries, thus indicating that continued efforts are needed to improve oral health care utilisation by inner-city preschool children.

  5. Solar Golden Arches

    NASA Image and Video Library

    2017-05-01

    The magnetic field lines between a pair of active regions formed a beautiful set of swaying arches rising up above them Apr. 24-26, 2017, as seen by NASA Solar Dynamics Observatory. The connection between opposing poles of polarity is visible in exquisite detail in this wavelength of extreme ultraviolet light. What we are really seeing are charged particles spinning along the magnetic field lines. Other field lines are traced as they reach out in other directions as well. Videos can be seen at https://photojournal.jpl.nasa.gov/catalog/PIA21604

  6. Considerations on Optimal Fluoride Intake using Dental Fluorosis and Dental Caries Outcomes – A Longitudinal Study

    PubMed Central

    Warren, John J.; Levy, Steven M.; Broffitt, Barbara; Cavanaugh, Joseph E.; Kanellis, Michael J.; Weber-Gasparoni, Karin

    2015-01-01

    Objectives The “optimal” intake of fluoride has been widely accepted for decades as between 0.05 and 0.07 mg fluoride per kilogram of body weight but is based on limited scientific evidence. The purpose of this paper is to present longitudinal fluoride intake data for children free of dental fluorosis in the early-erupting permanent dentition and free of dental caries in both the primary and early-erupting permanent teeth as an estimate of optimal fluoride intake. Methods Data on fluoride ingestion were obtained from parents of 602 Iowa Fluoride Study children through periodic questionnaires at the ages of 6 weeks, 3, 6, 9, 12, 16, 20, 24, 28, 32 and 36 months, and then at 6-month intervals thereafter. Estimates of total fluoride intake at each time point were made by summing amounts from water, dentifrice, and supplements as well as other foods and beverages made with or containing water. Caries data were obtained from examinations of children at ages 5 and 9 years, while fluorosis data were obtained from examinations only at age 9. Results The estimated mean daily fluoride intake for those children with no caries history and no fluorosis at age 9 was at or below 0.05 mgF/kg bw for nearly all time points through the first 48 months of life, and this level declined thereafter. Children with caries had generally slightly less intakes, while those with fluorosis generally had slightly higher intakes. Conclusions Given the overlap among caries/fluorosis groups in mean fluoride intake and extreme variability in individual fluoride intakes firmly recommending an “optimal” fluoride intake is problematic. PMID:19054310

  7. 35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED BETWEEN TOWER LEGS, AND ASHLAR MASONRY WALLS AND PYLONS Pen-and-ink drawing by project architect Alfred Eichler, 1934. - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  8. Dental changes evaluated with a 3D computer-assisted model analysis after long-term tongue retaining device wear in OSA patients.

    PubMed

    Chen, Hui; Lowe, Alan A; Strauss, Arthur M; de Almeida, Fernanda Riberiro; Ueda, Hiroshi; Fleetham, John A; Wang, Bangkang

    2008-05-01

    Oral appliances (OAs) have been used to treat obstructive sleep apnea (OSA) patients for decades. However, detailed dental side effects in long-term OA cases analyzed with an accurate three-dimensional (3D) measurement tool have seldom been reported. The purpose of this study is to evaluate dental side effects in five OSA patients, who had used a tongue retaining device (TRD) (with occasional other OA wear) for an average of 6 years and 4 months. The baseline and follow-up orthodontic study models were measured with a newly developed MicroScribe-3DX analysis system. High compliance of TRD wear was confirmed in all cases and different patterns and amounts of dental changes were observed. The most common appliance-induced dental changes included anterior and/or unilateral posterior open-bites and reduced anterior overjets. It was hypothesized that there might be two possible mechanisms for the TRD side effects--one is the forward pressure of the tongue upon the anterior dental arch and the other is the lateral pressure of the tongue upon the posterior arch. Considerations to correct the TRD dental side effects should be guided by these different mechanisms of the tongue on the dental arch. Possible solutions to minimize occlusal changes and maximize the benefits for OSA patients are also discussed.

  9. Relationship between performance in dental school and performance on a dental licensure examination: an eight-year study.

    PubMed

    Stewart, Carol M; Bates, Robert E; Smith, Gregory E

    2005-08-01

    This study assessed relationships between academic performance in dental school and "first attempt" performance on a state dental licensure examination for 1996-2003 graduates from the University of Florida College of Dentistry (UFCD). The 524 graduates were ranked into quartiles based on graduating GPA. Using analysis of variance (ANOVA), the students' mean exam score (or exam section score) for each respective quartile (n=131) was compared with mean score for graduates in the combined four quartiles (n=524). ANOVA assessments, by quartile, were performed for the following six measures: 1) overall composite score on the dental licensure exam, 2) clinical periodontics section, 3) clinical amalgam section, 4) combination of clinical periodontics and clinical amalgam, 5) laboratory (manikin exam) with a written prosthodontic exam, and 6) manikin exam without the prosthodontic exam. For the overall exam and all exam sections, a significant (p<0.001) relationship was found between higher mean exam scores and academic ranking in quartile 1. A significant relationship was found between performance (lower mean scores) and ranking in quartile 4 for all exam sections, with the exception of the clinical periodontal section. The results of this study indicate a correlation between performance in dental school and performance on the Florida dental licensure exam for 1996-2003 UFCD graduates.

  10. Utilization of dental health care services in context of the HIV epidemic- a cross-sectional study of dental patients in the Sudan

    PubMed Central

    2009-01-01

    Background HIV infected patients should be expected in the Sudanese dental health care services with an increasing frequency. Dental care utilization in the context of the HIV epidemic is generally poorly understood. Focusing on Sudanese dental patients with reported unknown HIV status, this study assessed the extent to which Andersen's model in terms of predisposing (socio-demographics), enabling (knowledge, attitudes and perceived risk related to HIV) and need related factors (oral health status) predict dental care utilization. It was hypothesized that enabling factors would add to the explanation of dental care utilization beyond that of predisposing and need related factors. Methods Dental patients were recruited from Khartoum Dental Teaching Hospital (KDTH) and University of Science and Technology (UST) during March-July 2008. A total of 1262 patients (mean age 30.7, 56.5% females and 61% from KDTH) were examined clinically (DMFT) and participated in an interview. Results A total of 53.9% confirmed having attended a dental clinic for treatment at least once in the past 2 years. Logistic regression analysis revealed that predisposing factors; travelling inside Sudan (OR = 0.5) were associated with lower odds and females were associated with higher odds (OR = 2.0) for dental service utilization. Enabling factors; higher knowledge of HIV transmission (OR = 0.6) and higher HIV related experience (OR = 0.7) were associated with lower odds, whereas positive attitudes towards infected people and high perceived risk of contagion (OR = 1.3) were associated with higher odds for dental care utilization. Among need related factors dental caries experience was strongly associated with dental care utilization (OR = 4.8). Conclusion Disparity in the history of dental care utilization goes beyond socio-demographic position and need for dental care. Public awareness of HIV infection control and confidence on the competence of dentists should be improved to minimize avoidance

  11. [The exposure dose of the sella turcica in panoramic dental radiography with an intraoral radiogenic source].

    PubMed

    Pastremoli, A; Cucchi, G; Ciminari, R

    1991-06-01

    Panoramic dental radiography using an intraoral X-ray source exposes critical organs, such as the crystalline and the thyroid, as well as organs of fundamental importance such as the pituitary gland, to X-rays. An experimental study was carried out to assess the exposure dose to the sella turcica during the radiological examination of the upper and lower dental arches using an X-ray source within the oral cavity. The comprehensive exposure dose for the upper and lower dental arches exceeded that found in orthopantomography (110 micro Gy/examination vs 47 micro Gy/examination) with errors which are respectively inferior to 15% and 30%. The authors conclude that the risk of provoking anatomical or functional changes of the pituitary gland is extremely remote using this type of examination.

  12. The relationship between dental anxiety and dental pain in children aged 18 to 59 months: a study in Recife, Pernambuco State, Brazil.

    PubMed

    Oliveira, Michelle Marie T; Colares, Viviane

    2009-04-01

    The aim of this study was to evaluate anxiety and pain related to dental treatment in children under the age of five years. This cross sectional study was carried out with 2,735 children of both sexes. Socioeconomic data, dental anxiety and dental pain experience, as well as the assessment of the child's oral health status, were obtained through a questionnaire answered by the child's parent or guardian. Dental anxiety was measured using the Dental Anxiety Question (DAQ). The prevalence of dental anxiety was 34.7% and that of dental pain was 9.1%. There was an association between these two variables (p < 0.0001). There was also an association between dental pain, age, family income and assessment of oral health status. The poorest rating of the child's oral health and the lowest family income were correlated with the highest percentages of a history of dental pain. Dental anxiety was related to a history of dental pain in children under the age of five years.

  13. Ambient resonance of Mesa Arch, Canyonlands National Park, Utah

    NASA Astrophysics Data System (ADS)

    Starr, Alison M.; Moore, Jeffrey R.; Thorne, Michael S.

    2015-08-01

    We analyzed the resonance characteristics of a prominent natural arch in Canyonlands National Park, Mesa Arch, as measured from ambient seismic data. Evaluating spectral and polarization attributes, we distinguished the first four resonant frequencies of the arch, 2.9, 6.0, 6.9, and 8.5 Hz, as well as basic properties of the associated mode shapes. We then affirmed experimental data using 3-D numerical modal analysis, providing estimates of material properties and clarifying vibrational mode shapes. Monitoring resonant frequencies over time, we searched for shifts associated with changing environmental conditions and long-term progressive damage. We measured ~3% direct daily variation in resonant frequency associated with changing rock temperature, thermal stress, and stiffening of the rock matrix. Independent tilt data showed similar diurnal cycles associated with thermoelastic stresses and deformation of the arch. We observed no permanent resonant frequency shifts related to irreversible damage of Mesa Arch during our study period.

  14. Comparison of mesiodistal crown dimension and arch width in subjects with and without hypodontia.

    PubMed

    Fekonja, Anita

    2013-06-01

    Tooth agenesis is one of the most common anomalies in the development of the human dentition and may have wider associations in the development of the dentition including tooth size. This study aimed to compare mesiodistal crown dimension and arch widths between subjects with hypodontia and subjects without hypodontia (control group). Dental casts were measured of 55 hypodontia patients and 55 patients with total permanent dentition (control group). Tooth agenesis was evaluated for hypodontia, excluding the third molars, from the panoramic radiograph. Mesiodistal crown dimensions were recorded by measuring all erupted teeth on study models with a digital Mitutoyo caliper (Mitutoyo U.K. Ltd, United Kingdom). Patients with hypodontia had smaller mesiodistal tooth dimensions than the control group, and this difference was statistically significant (p < 0.05) for all teeth in both genders. Upper lateral incisors, lower central incisors, and lower second molars showed the highest difference in tooth dimension. Also, the intercanine and intermolar arch widths in the hypodontia group were statistically significantly reduced (p < 0.05) compared with the control group. The findings indicate that the mesiodistal crown dimensions and arch widths are reduced in hypodontia patients. This should be taken into account when planning orthodontic treatment. Congenital absence of permanent teeth has direct clinical implications. Early detection of the number of missing teeth and evaluation of the tooth size and arch width is of immense value in the planning and managing treatment with a multidisciplinary team approach to achieve an aesthetic and functional dentition and reduce the complications of hypodontia. © 2013 Wiley Periodicals, Inc.

  15. Multivariate study of factors influencing primary dental implant stability.

    PubMed

    Mesa, Francisco; Muñoz, Ricardo; Noguerol, Blas; de Dios Luna, Juan; Galindo, Pablo; O'Valle, Francisco

    2008-02-01

    The purpose was to determine by multivariate analysis in a large series of dental implants the variables associated with primary endosseous dental implant stability (DIS). A 10-year retrospective study was conducted of 1084 Brånemark implants placed in 316 patients. Clinical variables (age, gender, smoking habit, and periodontal status), implant diameter, implant length, and Periotest values (PTVs) were analyzed in bivariate and multivariate studies in order to determine their influence on DIS, using a cut-off PTV value of -2. The site of implant insertion showed the strongest association with primary DIS failure among the study variables. Implants in the anterior mandible had a 6.43-fold lower risk of primary DIS risk vs. those at other sites [95% confidence interval (CI) 3.28-12.61], and implants in the maxillary had a 2.70-fold higher risk of primary DIS failure vs. those in the mandible (95% CI 1.82-4). Among other variables, females had a 1.54-fold higher risk of primary DIS failure vs. males (95% CI 1.88-2.22) and implants <15 mm in length had a 1.49-fold higher risk of failure vs. longer implants (95% CI 1.09-2.04). According to these findings, primary DIS failure is more likely in females, at sites other than the anterior mandible, and with dental implants shorter than 15 mm, at least when non-threaded titanium implants are used. These data may be of value in the identification of patients at a high risk of primary DIS failure with immediate implant loading.

  16. Study comparing midazolam and nitrous oxide in dental anxiety control.

    PubMed

    Pereira-Santos, Darklilson; Brêda-Júnior, Marcus Antônio; Ferraz, Emanuela Prado; Crippa, Grasiele Edilaine; de Oliveira, Fabíola Singaretti; da Rocha-Barros, Valdemar Mallet

    2013-09-01

    The purpose of this study is to comparatively assess the effect of midazolam and nitrous oxide associated with oxygen, in lower third molar extractions, on the change in the anxiety level of patients by salivary cortisol dosage. Twenty-eight male patients underwent lower third molar extraction under sedation with midazolam and nitrous oxide. Objective (salivary cortisol dosage) and subjective (Corah Dental Anxiety Scale) data have been obtained. By salivary cortisol, 40 minutes after midazolam administration, there has been a statistically significant difference compared with the mean baseline value. Midazolam was the most effective sedation method for reducing salivary cortisol level.

  17. A special place for learning Minnesota's dental study clubs.

    PubMed

    Anderson, Jay A

    2002-01-01

    With this issue, NWD begins a look into the varied and versatile dental study clubs that are a part of the continuing education landscape in Minnesota. To the "question of the month" in a recent issue of JADA, 86% of respondents said they had participated in at least one such group. For members, long-time or newer, they are a passion, a permission, and a perfectly collegial solution to keeping current. Look inside, then look around. You can find what you need, and possibly what you didn't even know you were looking for.

  18. Key Techniques and Risk Management for the Application of the Pile-Beam-Arch (PBA) Excavation Method: A Case Study of the Zhongjie Subway Station

    PubMed Central

    Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

    2014-01-01

    The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area. PMID:25221783

  19. Dental archforms in dentoalveolar Class I, II and III.

    PubMed

    Slaj, Martina; Spalj, Stjepan; Pavlin, Dubravko; Illes, Davor; Slaj, Mladen

    2010-09-01

    To test the hypothesis that no differences exist in dental arch dimensions between dentoalveolar Classes I, II, and III, and between male and female subjects, as measured on virtual three-dimensional (3D) models. Samples included randomly selected plaster dental casts of 137 white patients (43 Class I, 50 Class II, and 44 Class III) from the Department of Orthodontics, School of Dental Medicine, University of Zagreb, Croatia. Dental models were scanned and digitized using ATOS II SO ("Small Objects") scanning technology (GOM mbH, Braunschweig, Germany). Eight linear and two proportional measurements were calculated for both upper and lower dental arches. In men, a significant difference in the upper dental arch was present in the incisor region, and in the lower dental arch, differences were found in intercanine and intermolar widths (P < .05). Significant differences were noted between male groups in the upper molar depth dimension (P = .022) and in the lower molar and canine depth dimensions (P < .05). Class III males had the greatest lower molar and canine width/depth ratios and the smallest lower canine depth/molar depth ratio. Class III women had wider and shorter mandibular arches when compared with Class I and Class II females. The hypothesis was rejected. The dimensions of the dental arches are related to gender and to dentoalveolar class. Class I and II subjects have similar dimensions of maxillary dental arch, but Class II subjects have a transverse deficit in the mandible. In Class III subjects, the maxillary dental arch is insufficient in transverse and sagittal dimensions, and the mandibular arch dominates in the transverse but not in the sagittal dimension.

  20. Pioneering Strategies for Relieving Dental Anxiety in Hearing Impaired Children: a Randomized Controlled Clinical Study.

    PubMed

    Chandrasekhar, Shalini; Madu, Ghanashyam Prasad; Ambati, Naga Radhakrishna; Suravarapu, Pavani Reddy; Uppu, Kalyani; Bolla, Deepthi

    2017-06-01

    Hearing impaired children have a problem in understanding and comprehending with dental treatments. Visual language is the sensible answer of how to improve communication with them. To evaluate the applicability of dental sign language in Hearing impaired children in relieving anxiety during stressful dental treatment by improving their means of communication. This randomized clinical trial was carried out in the Department of Pedodontics and Preventive Dentistry which included 40 Hearing Impaired children meeting inclusion criteria. The selected children were randomly divided into the study and control group comprising of 20 each. In the control group, initial oral examination and dental treatment (oral prophylaxis and class I restoration) were performed without the use of dental sign language. In the study group, the dental sign language specific to dental treatment was educated and during their subsequent visit to the dental clinic after dental sign language reinforcement, oral prophylaxis and class I restoration were done. Subjective and objective measurements of anxiety were recorded for both groups using facial image scale (FIS), pulse oximeter and electronic blood pressure apparatus to compare for correlation. The obtained data were subjected to statistical analysis using unpaired t-test. There was a statistically significant reduction in the anxiety levels (p< 0.05) in the study group compared to the control group. Dental sign language was effective in reducing the level of anxiety in children who are hard of hearing. Dental sign language was able to improve behavior positively during dental treatment and may also aid in developing a positive dental attitude among children who are hard of hearing.

  1. Traumatic Dental Injuries Prevalence and their Impact on Self-esteem among Adolescents in India: A Comparative Study.

    PubMed

    Goyal, Nikita; Singh, Simarpreet; Mathur, Anmol; Makkar, Diljot Kaur; Aggarwal, Vikram Pal; Sharma, Anshika; Kaur, Puneet

    2017-08-01

    Adolescents are mostly injured during sport activities, traffic accidents and some forms of violence which may lead to traumatic injuries. Traumatic injuries not only pose a health risk worldwide but are also regarded among serious social problems. Poor oral health has been related to poor social relationships that affect the ability to learn and grow which may lead to reduced self-esteem. This study was conducted to compare self-esteem of adolescents with and without anterior Traumatic Dental Injury (TDI). A population based comparative study was conducted among 10 to 17 years old adolescents from November 2014 to January 2016. The study sample comprised of 424 controls and 212 cases with 2:1 control-to-case ratio that were selected by four examiners along with a gold standard examiner. TDI was recorded using Ellis classification and self-esteem was recorded using Rosenberg's Self-Esteem Scale (RSES). For comparing self-esteem of cases and controls according to RSES questions, t-test is used. Odds ratio (OR) was utilized to assess and compare the self-esteem according to high and low esteem in cases and controls. Ellis Class I, Ellis Class II and Ellis Class III fractures were observed in 53.3%, 33.49% and 13.20% of cases, respectively. The maxillary arch was the most affected (72.48%) and on the hierarchy of causes, this study found that on most occasions dental injuries were caused by sports (40.09%). The total mean score of RSES in cases (23.16) and in controls (24.43) was also statistically significant (p<0.001). Improving oral health in schools may contribute considerably to increase the self-esteem of adolescents in a positive direction and help them in becoming socially competent adults.

  2. Traumatic Dental Injuries Prevalence and their Impact on Self-esteem among Adolescents in India: A Comparative Study

    PubMed Central

    Singh, Simarpreet; Mathur, Anmol; Makkar, Diljot Kaur; Aggarwal, Vikram Pal; Sharma, Anshika; Kaur, Puneet

    2017-01-01

    Introduction Adolescents are mostly injured during sport activities, traffic accidents and some forms of violence which may lead to traumatic injuries. Traumatic injuries not only pose a health risk worldwide but are also regarded among serious social problems. Poor oral health has been related to poor social relationships that affect the ability to learn and grow which may lead to reduced self-esteem. Aim This study was conducted to compare self-esteem of adolescents with and without anterior Traumatic Dental Injury (TDI). Materials and Methods A population based comparative study was conducted among 10 to 17 years old adolescents from November 2014 to January 2016. The study sample comprised of 424 controls and 212 cases with 2:1 control-to-case ratio that were selected by four examiners along with a gold standard examiner. TDI was recorded using Ellis classification and self-esteem was recorded using Rosenberg’s Self-Esteem Scale (RSES). For comparing self-esteem of cases and controls according to RSES questions, t-test is used. Odds ratio (OR) was utilized to assess and compare the self-esteem according to high and low esteem in cases and controls. Results Ellis Class I, Ellis Class II and Ellis Class III fractures were observed in 53.3%, 33.49% and 13.20% of cases, respectively. The maxillary arch was the most affected (72.48%) and on the hierarchy of causes, this study found that on most occasions dental injuries were caused by sports (40.09%). The total mean score of RSES in cases (23.16) and in controls (24.43) was also statistically significant (p<0.001). Conclusion Improving oral health in schools may contribute considerably to increase the self-esteem of adolescents in a positive direction and help them in becoming socially competent adults. PMID:28969286

  3. Articulated dental cast analysis of asymptomatic and symptomatic populations

    PubMed Central

    Cordray, Frank E

    2016-01-01

    Dental instrumentation has long provided insight into the mechanism of musculo-skeletal function of the gnathic system. While large population studies associate dental arch displacement (DAD), especially laterally, with symptoms, mandibular condyle displacement (CD) resulting from DAD has not been targeted as possibly etiologic in the production of common muscle contraction headache (CMCH) and temporo-mandibular dysfunction (TMD). The objective was to evaluate the three-dimensional nature of DAD and CD between the seated condylar position (SCP) and the intercuspal position (ICP) and to compare results derived from large deprogrammed asymptomatic and symptomatic populations. A total of 1 192 sets of dental casts collected from asymptomatic and symptomatic populations were articulated in the SCP. The initial occlusal contact, DAD, and condylar displacement were evaluated for frequency, direction, and magnitude of displacement between the SCP and ICP. The data revealed significant displacement between the SCP and ICP of the condyles (displaced most frequently inferior (down) and posterior (distal)) and substantially increased frequency and magnitude of displacement of the dental arches (with posterior premature occlusal contacts, increased overjet, decreased overbite, midline differences, and occlusal classification changes) in symptomatic subjects. These discrepancies were statistically significant and clinically significant. The data support the concept of increased DAD and CD with dysfunction. Transverse condylar displacement, commonly presenting with dental cross bite, may be associated with CMCH and TMD. Displacement of the mandibular condyle may be an etiologic factor in CMCH and dysfunction of the temporo-mandibular joint. PMID:27357324

  4. A Study to Determine the Optimal Frequency for Conducting Periodic Dental Examinations, Recruit Needs. Part II.

    DTIC Science & Technology

    1980-06-01

    HEALTH CARE STUDIES DIVISION REPORT #80-004 A STUDY TO DETERMINE THE OPTIMAL FREQUENCY FOR CONDUCTING PERIODIC DENTAL EXAMINATIONS RECRUIT NEEDS (Part...CONDUCTING PERIODIC DENTAL EXAMINATIONS - RECRUIT July 1979 to June 1980 NEEDS PART II G. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(*) 8. CONTRACT OR GRANT...KEY WORDS (Continue an reveree side if neceeary end Identify by block number) Dental ; Recruits; Care needs; Treatment Time; Age; Oral health 2a *srhA&T

  5. Critical Transitions in Early Embryonic Aortic Arch Patterning and Hemodynamics

    PubMed Central

    Kowalski, William J.; Dur, Onur; Wang, Yajuan; Patrick, Michael J.; Tinney, Joseph P.; Keller, Bradley B.; Pekkan, Kerem

    2013-01-01

    Transformation from the bilaterally symmetric embryonic aortic arches to the mature great vessels is a complex morphogenetic process, requiring both vasculogenic and angiogenic mechanisms. Early aortic arch development occurs simultaneously with rapid changes in pulsatile blood flow, ventricular function, and downstream impedance in both invertebrate and vertebrate species. These dynamic biomechanical environmental landscapes provide critical epigenetic cues for vascular growth and remodeling. In our previous work, we examined hemodynamic loading and aortic arch growth in the chick embryo at Hamburger-Hamilton stages 18 and 24. We provided the first quantitative correlation between wall shear stress (WSS) and aortic arch diameter in the developing embryo, and observed that these two stages contained different aortic arch patterns with no inter-embryo variation. In the present study, we investigate these biomechanical events in the intermediate stage 21 to determine insights into this critical transition. We performed fluorescent dye microinjections to identify aortic arch patterns and measured diameters using both injection recordings and high-resolution optical coherence tomography. Flow and WSS were quantified with 3D computational fluid dynamics (CFD). Dye injections revealed that the transition in aortic arch pattern is not a uniform process and multiple configurations were documented at stage 21. CFD analysis showed that WSS is substantially elevated compared to both the previous (stage 18) and subsequent (stage 24) developmental time-points. These results demonstrate that acute increases in WSS are followed by a period of vascular remodeling to restore normative hemodynamic loading. Fluctuations in blood flow are one possible mechanism that impacts the timing of events such as aortic arch regression and generation, leading to the variable configurations at stage 21. Aortic arch variations noted during normal rapid vascular remodeling at stage 21 identify a

  6. Access Barriers to Dental Health Care in Children with Disability. A Questionnaire Study of Parents.

    PubMed

    Gerreth, Karolina; Borysewicz-Lewicka, Maria

    2016-03-01

    A patient's with disability everyday life is rife with many limitations such as architectural, transport, information as well as medical, psychological, legal, economic and social barriers. The aim of this study was to evaluate access to dental health care of special-care schoolchildren with intellectual disability on the basis of their parents' opinion. A questionnaire survey was carried out among 264 parents/caregivers of children from eight special-care schools in Poznan (Poland). Close-ended questions concerned children's barriers in access to dental care and parents' satisfaction with their children's dental care. Only 31.8% parents/caregivers did not have any problems with access to dental care and the most commonly reported barrier to obtaining dental care was protracted waiting time for a visit (36.7%). Most commonly, children were treated in dental surgery conditions (90.1%). Only 42.1% respondents were satisfied with their children's dental care. The research revealed that there is a need to improve the access of children with disability to dental care. Hence, it seems to be beneficial to set up specialist dental surgeries in special-care schools which would improve the access of children with disability to prophylaxis as well as dental treatment. © 2015 John Wiley & Sons Ltd.

  7. Three-dimensional optical high-resolution profiler with a large observation field: foot arch behavior under low static charge studies.

    PubMed

    Meneses, Jaime; Gharbi, Tijani; Cornu, Jean Yves

    2002-09-01

    Our aim is to describe a method for detecting small deformations from a three-dimensional (3D) shape of large lateral dimensions. For this purpose the measurement method is based on the simultaneous utilization of several 3D optical systems and the phase-shifting technique. In this way, the following problems appear: optical distortion due to the large field observed, nonlinear phase-to-height conversion, conversion of image coordinates into object coordinates for each 3D optical system, and coordinate unification of all optical systems. The resolution is 50 microm with a field of view of 320 mm x 150 mm. We used this system to study the 3D human foot arch deformation under low loads in vivo. First results indicate the hysteresis behavior of the human foot under a low load (50 to 450 N).

  8. Comparative study of mechanical properties of dental restorative materials and dental hard tissues in compressive loads

    PubMed Central

    Lee, Jong Yeop

    2014-01-01

    There are two objectives. One is to show the differences in the mechanical properties of various dental restorative materials compared to those of enamel and dentin. The other is to ascertain which dental restorative materials are more suitable for clinical treatments. Amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy were processed as dental restorative material specimens. The specimens (width, height, and length of 1.2, 1.2, and 3.0 mm, respectively) were compressed at a constant loading speed of 0.1 mm/min. The maximum stress (115.0 ± 40.6, 55.0 ± 24.8, 291.2 ± 45.3, 274.6 ± 52.2, 2206.0 ± 522.9, and 953.4 ± 132.1 MPa), maximum strain (7.8% ± 0.5%, 4.0% ± 0.1%, 12.7% ± 0.8%, 32.8% ± 0.5%, 63.5% ± 14.0%, and 45.3% ± 7.4%), and elastic modulus (1437.5 ± 507.2, 1548.4 ± 583.5, 2323.4 ± 322.4, 833.1 ± 92.4, 3895.2 ± 202.9, and 2222.7 ± 277.6 MPa) were evident for amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy, respectively. The reference hardness value of amalgam, dental ceramic, gold alloy, dental resin, zirconia, and titanium alloy was 90, 420, 130–135, 86.6–124.2, 1250, and 349, respectively. Since enamel grinds food, its abrasion resistance is important. Therefore, hardness value should be prioritized for enamel. Since dentin absorbs bite forces, mechanical properties should be prioritized for dentin. The results suggest that gold alloy simultaneously has a hardness value lower than enamel (74.8 ± 18.1), which is important in the wear of the opposing natural teeth, and higher maximum stress, maximum strain, and elastic modulus than dentin (193.7 ± 30.6 MPa, 11.9% ± 0.1%, 1653.7 ± 277.9 MPa, respectively), which are important considering the rigidity to absorb bite forces. PMID:25352921

  9. Prevalence and pattern of partial edentulism among dental patients attending College of Dentistry, Aljouf University, Saudi Arabia

    PubMed Central

    Fayad, Mostafa I.; Baig, Mohamed N.; Alrawaili, Abdulrazaq M.

    2016-01-01

    Objective: The current study aimed to determine the prevalence and pattern of partial edentulism among dental patients attending the College of Dentistry, Aljouf University, Saudi Arabia. Patients and Methods: A total of 142 patients were selected, and the prevalence of partial edentulism among the selected patient was recorded. Patients were grouped into three age groups; Group I: 21–30 years, Group II: 31–40 years, and Group III: 41–50 years. Kennedy's classification was used to determine the pattern of partially edentulous arches. Modification areas were not included in the assessment to avoid complexity. Data was analyzed using the Statistical Package for the Social Sciences version 20.0 for windows. Results: The results showed that the occurrence of Kennedy Class III partial edentulism was 67.2 % in the maxillary arch and 64.1% in the mandibular arch. Followed by Class II in both maxillary and mandibular arch with an average of 16.3 % in maxillary arch and14.8% in the mandibular arch. Based on these results, class III has the highest prevalence in group II (31- 40 years). Class I and class II have the highest incidence among group III Patients (41–50 years). Conclusions: Among selected patients, Class III dental arch was the most prevalent pattern in maxillary and mandibular arches. Class IV being the least dominant pattern between all classes. There are a rise in Kennedy Class I and Kennedy Class II pattern and a decline in Class III and Class IV with an increase in age. PMID:28217535

  10. Which is a stronger indicator of dental caries: oral hygiene, food, or beverage? A clinical study.

    PubMed

    Jain, Poonam; Gary, Julie J

    2014-01-01

    Dental caries is a multifactorial disease with various risk factors. Oral hygiene and dietary factors--specifically, the consumption of snacks and beverages with added sugars--have been shown to be risk indicators for this disease. It is critical for dental professionals to understand the relative roles of each of these food categories in the dental caries process. This article presents a cross-sectional study of 76 people living in a Southern Illinois fluoridated community. The amount of sugar-sweetened beverages, snack food consumption, plaque index, and age showed statistically significant relationships with the outcome variable--dental caries (P < 0.05). The results indicated that dietary factors and oral hygiene both contribute equally to dental caries in young adults living in a fluoridated community. Sugar-sweetened beverage consumption was a much stronger indicator of dental caries than snack food consumption in our study population.

  11. Parental attitudes and perceptions affecting children's dental behaviour in Greek population. A clinical study.

    PubMed

    Kyritsi, M A; Dimou, G; Lygidakis, N A

    2009-01-01

    This was to investigate the relationship of children's behaviour during dental treatment to parental dental attitudes and perceptions in a definitive population of Greek children in Athens. 88 children aged 3-11 years and their parents, attending the Community Dental Centre for Children in Athens, participated. A questionnaire including demographic information, questions regarding parents' dental experience and anxiety (M-DAS test), as well as questions regarding expectant behaviour of each child and his/her dental anxiety level (parental version of the CFSS -Dental Subscale), was completed by the parents during the first examination appointment. During the two following operative sessions each child's behaviour was recorded and evaluated using the Frankl Scale. Collected data were statistically analyzed using a SPSS statistical program. No significant difference was found between a child's actual behaviour and gender, nationality, frequency of parent's dental visits, parental dental fear (M-DAS) and previous medical experience of the child (p>0.001). In contrast, age (p=0.005), previous child's dental fear (p=0.081), previous child's dental behaviour (p<0.0001), predicted by the parent behaviour (p<0.0001) and parental version of CFSS-DS (p<0.001), revealed statistically significant associations to child's behaviour during treatment. According to the present study in Greek children, children's behaviour during dental treatment is related to age, previous dental fear and experience and behaviour prediction by the parents. Parents' estimations regarding their children's fear and behaviour could be a useful predictor of child's level of cooperation during dental treatment.

  12. Dental amalgam and urinary mercury concentrations: a descriptive study

    PubMed Central

    2013-01-01

    Background Dental amalgam is a source of elemental and inorganic mercury. The safety of dental amalgam in individuals remains a controversial issue. Urinary mercury concentrations are used to assess chronic exposure to elemental mercury. At present, there are no indications of mercury-associated adverse effects at levels below 5 μg Hg/g creatinine (Cr) or 7 μg Hg/L (urine). The purpose of the present study is to determine the overall urinary mercury level in the Canadian general population in relation to the number of dental amalgam surfaces. Methods Data come from the 2007/09 Canadian Health Measures Survey, which measured urinary mercury concentrations in a nationally representative sample of 5,418 Canadians aged 6–79 years. Urinary mercury concentrations were stratified by sex, age, and number of dental amalgam surfaces. Results The overall mean urinary mercury concentration varied between 0.12 μg Hg/L and 0.31 μg Hg/L or 0.13 μg Hg/g Cr and 0.40 μg Hg/g Cr. In general, females showed slightly higher mean urinary mercury levels than men. The overall 95th percentile was 2.95 μg Hg/L, the 99th percentile was 7.34E μg Hg/L, and the 99.9th percentile was 17.45 μg Hg/L. Expressed as μg Hg/g Cr, the overall 95th percentile was 2.57 μg Hg/g Cr, the 99th percentile was 5.65 μg Hg/g Cr, and the 99.9th percentiles was 12.14 μg Hg/g Cr. Overall, 98.2% of participants had urinary mercury levels below 7 μg Hg/L and 97.7% had urinary mercury levels below 5 μg Hg/g Cr. All data are estimates for the Canadian population. The estimates followed by the letter “E” should be interpreted with caution due to high sampling variability (coefficient of variation 16.6%-33.3%). Conclusions The mean urinary mercury concentrations in the general Canadian population are significantly lower than the values considered to pose any risks for health. PMID:24015978

  13. Thermal-lens study of semiconductor nanoparticles embedded in restorative dental resin

    NASA Astrophysics Data System (ADS)

    Alves, Leandro P.; Pilla, Viviane; Iwazaki, Adalberto N.; Barja, Paulo R.; Munin, Egberto

    2013-02-01

    Thermal Lens (TL) and spectroscopic characterizations were performed in CdSe/ZnS core-shell quantum dots (QDs) embedded into two commercial dental resin composites. The thermal-optical studies were performed in CdSe/ZnS QDs (core size Φ= 4.1 nm) and PMMA-encapsulated CdSe/ZnS (Φ= 3.7 nm) embedded in restorative dental resins at concentration of 0.025 and 0.42 % in mass, respectively. The thermal diffusivity (D) results are characteristics of the dental resin composites studied. Photoacoustic (PA) technique results for the dental resin composites support the TL results.

  14. A computational study of the role of the aortic arch in idiopathic unilateral vocal-fold paralysis

    PubMed Central

    Williams, Megan J.; Ayylasomayajula, Avinash; Behkam, Reza; Bierhals, Andrew J.; Jacobs, M. Eileen; Edgar, Julia D.; Paniello, Randal C.; Barkmeier-Kraemer, Julie M.

    2014-01-01

    Unilateral vocal-fold paralysis (UVP) occurs when one of the vocal folds becomes paralyzed due to damage to the recurrent laryngeal nerve (RLN). Individuals with UVP experience problems with speaking, swallowing, and breathing. Nearly two-thirds of all cases of UVP is associated with impaired function of the left RLN, which branches from the vagus nerve within the thoracic cavity and loops around the aorta before ascending to the larynx within the neck. We hypothesize that this path predisposes the left RLN to a supraphysiological, biomechanical environment, contributing to onset of UVP. Specifically, this research focuses on the identification of the contribution of the aorta to onset of left-sided UVP. Important to this goal is determining the relative influence of the material properties of the RLN and the aorta in controlling the biomechanical environment of the RLN. Finite element analysis was used to estimate the stress and strain imposed on the left RLN as a function of the material properties and loading conditions. The peak stress and strain in the RLN were quantified as a function of RLN and aortic material properties and aortic blood pressure using Spearman rank correlation coefficients. The material properties of the aortic arch showed the strongest correlation with peak stress [ρ = −0.63, 95% confidence interval (CI), −1.00 to −0.25] and strain (ρ = −0.62, 95% CI, −0.99 to −0.24) in the RLN. Our results suggest an important role for the aorta in controlling the biomechanical environment of the RLN and potentially in the onset of left-sided UVP that is idiopathic. PMID:25477351

  15. A computational study of the role of the aortic arch in idiopathic unilateral vocal-fold paralysis.

    PubMed

    Williams, Megan J; Ayylasomayajula, Avinash; Behkam, Reza; Bierhals, Andrew J; Jacobs, M Eileen; Edgar, Julia D; Paniello, Randal C; Barkmeier-Kraemer, Julie M; Vande Geest, Jonathan P

    2015-02-15

    Unilateral vocal-fold paralysis (UVP) occurs when one of the vocal folds becomes paralyzed due to damage to the recurrent laryngeal nerve (RLN). Individuals with UVP experience problems with speaking, swallowing, and breathing. Nearly two-thirds of all cases of UVP is associated with impaired function of the left RLN, which branches from the vagus nerve within the thoracic cavity and loops around the aorta before ascending to the larynx within the neck. We hypothesize that this path predisposes the left RLN to a supraphysiological, biomechanical environment, contributing to onset of UVP. Specifically, this research focuses on the identification of the contribution of the aorta to onset of left-sided UVP. Important to this goal is determining the relative influence of the material properties of the RLN and the aorta in controlling the biomechanical environment of the RLN. Finite element analysis was used to estimate the stress and strain imposed on the left RLN as a function of the material properties and loading conditions. The peak stress and strain in the RLN were quantified as a function of RLN and aortic material properties and aortic blood pressure using Spearman rank correlation coefficients. The material properties of the aortic arch showed the strongest correlation with peak stress [ρ = -0.63, 95% confidence interval (CI), -1.00 to -0.25] and strain (ρ = -0.62, 95% CI, -0.99 to -0.24) in the RLN. Our results suggest an important role for the aorta in controlling the biomechanical environment of the RLN and potentially in the onset of left-sided UVP that is idiopathic. Copyright © 2015 the American Physiological Society.

  16. The impact of kiddy dentures on maxillary arch growth.

    PubMed

    Shih, Wen-Yu; Wu, Fu-Ya

    2016-09-01

    Kiddy dentures are used to restore the self-confidence, chewing function, and pronunciation of children or when a care provider is concerned about the loss of incisor teeth. However, most studies to date have investigated normal dental arch development, and only a few have explored the effect of kiddy dentures on upper arch development. Fourteen Taiwanese children (7 male and 7 female) who were wearing kiddy dentures due to the loss of their upper anterior teeth were enrolled in this study. Inclusion criteria were the premature loss of maxillary incisors, the patient wearing kiddy dentures with both upper primary first molars as abutments, and the patient having complete records allowing a full longitudinal clinical follow-up. Dental casts were obtained immediately (T1), at 6 months (T2), and at 12 months (T3) after delivery of the kiddy dentures. The measured parameters included intercanine width (ICW, C1 to C2), interfirst molar width (IDW, D1 to D2), and intersecond molar width (IEW, E1 to E2). All the measurements were performed by one experienced examiner using a vernier caliper. The mean ages of the enrolled children for the periods T1, T2, and T3 were 43.8 ± 8.3 months, 50.6 ± 8.5 months, and 56.7 ± 8.4 months, respectively. There was no significant difference in gender when ICW, IDW, and IEW were compared. The mean changes in ICW values were 23.6 ± 6.2 mm, 24.2 ± 5.9 mm, and 24.6 ± 6.4 mm for T1, T2, and T3, respectively. There were statistically significant differences between T1 and T2, T2 and T3, and T1 and T3 for ICW (p < 0.05). The mean changes in IDW were 25.7 ± 8.4 mm, 25.8 ± 9.0 mm, and 25.8 ± 9.1 mm for T1, T2, and T3, respectively. There was no statistically significant difference between T1 and T2, T2 and T3, and T1 and T3. The mean changes in IEW were 30.6 ± 10.1 mm, 31.2 ± 8.8 mm, and 31.3 ± 8.2 mm for T1, T2, and T3, respectively. There was statistical significance between T1 and T2 or T1 and

  17. Epidemiologic study of dental emergencies among utilizers in an insured population in Washington, USA.

    PubMed

    Ngim, C H; Peterson, D R; Milgrom, P

    1984-10-01

    This is a study of the epidemiology of dental emergencies based on information abstracted from the microfilmed dental claim forms of a large American insurance program in 1981-82. Overall, about 4% of all dental visits were classifiable as emergencies. There were significant seasonal and age variations in dental emergencies. There was no variation with respect to geographic regions in the State of Washington (USA) or sex. Paradoxically, residents in regions having fluoridated water supplies were at equal risk of developing dental emergencies due to dental caries, relative to those residing in non-fluoridated regions. There was also no difference in risk associated with insurance deductibles, although generally deductibles are thought to deter first-contact visits.

  18. [Study of peripheral sensorineural function in a cohort of dental hygienists].

    PubMed

    Ronchese, F; Bovenzi, M

    2011-01-01

    The aim of this study was to investigate over time the changes in thermotactile and vibrotactile sensitivity in a cohort of dental hygiene students exposed to high-frequency vibration from dental tools. Thermal perception thresholds for warmth and cold (TPT in degrees C) and vibrotactile perception thresholds (VPT in ms-2 r.m.s) at 31.5 Hz and 125 Hz were measured at the fingertips of the 2nd digit and 5th digit of both hands in 52 controls and 30 dental hygiene students. At baseline, there were no significant differences in either TPT or VPT between the two groups. No significant changes in tactile sensitivity were observed in the dental hygienists over 1-year follow-up period. In conclusion, shortterm exposure to high-frequency vibration from dental tools did not affect tactile sensitivity in a cohort of young dental hygienists.

  19. A qualitative study of limited access permit dental hygienists in Oregon.

    PubMed

    Battrell, Ann M; Gadbury-Amyot, Cynthia C; Overman, Pamela R

    2008-03-01

    Many states have adopted alternative oral health care delivery systems that include expanded roles for dental hygienists. This qualitative study was designed to evaluate the impact of the Limited Access Permit (LAP) legislation in Oregon and to understand the relationship between dental hygienists and dentists within this delivery system. The snowball sampling technique was used to identify LAP dental hygienists and collaborating dentists. The snowball sampling technique begins with the identification of a known expert in the field who serves as the initial "sampling unit." Subsequent individuals are then recommended, or nominated, to the investigator by the initial study participant and are selected based upon the need to fill in or extend information. The final sample consisted of seven LAP dental hygienists and two collaborating dentists. Interviews, field observations, and document analysis were utilized for data collection. Factors that led to the creation of LAP dental hygiene practice, current LAP practice, personal characteristics, relationships between LAP dental hygienists and dentists, and the impact that LAP dental hygienists have had on access to oral health care were explored. Data revealed that the Oregon legislature twice expanded the LAP scope of practice to increase access to oral health care services. LAP dental hygienists practice in community and school-based settings. Common characteristics of LAP dental hygienists include entrepreneurship, lifelong learning, and a commitment to underserved populations. The findings from this study indicate that LAP dental hygienists and collaborating dentists have positive relationships. No evidence of lower quality of care in unsupervised dental hygiene practices was found. However, the impact of the LAP legislation is still unknown due to the limited numbers of LAP dental hygienists and the early nature of the LAP practice.

  20. Social capital and dental pain in Brazilian northeast: a multilevel cross-sectional study

    PubMed Central

    2013-01-01

    Background There is limited evidence on possible associations between social determinants and dental pain. This study investigated the relationship of neighborhood and individual social capital with dental pain in adolescents, adults and the elderly. Methods A population-based multilevel study was conducted involving 624 subjects from 3 age groups: 15–19, 35–44 and 65–74 years. They were randomly selected from 30 census tracts in three cities in the State of Paraíba, Brazil. A two-stage cluster sampling was used considering census tracts and households as sampling units. The outcome of study was the presence of dental pain in the last 6 months. Information on dental pain, demographic, socio-economic, health-related behaviors, use of dental services, self-perceived oral health and social capital measures was collected through interviews. Participants underwent a clinical examination for assessment of dental caries. Neighborhood social capital was evaluated using aggregated measures of social trust, social control, empowerment, political efficacy and neighborhood safety. Individual social capital assessment included bonding and bridging social capital. Multilevel logistic regression was used to test the relationship of neighborhood and individual social capital with dental pain after sequential adjustment for covariates. Results Individuals living in neighborhoods with high social capital were 52% less likely to report dental pain than those living in neighborhoods with low social capital (OR = 0.48, 95% CI = 0.27-0.85). Bonding social capital (positive interaction) was independently associated with dental pain (OR = 0.88, 95% CI = 0.80-0.91). Last dental visit, self-perceived oral health and number of decayed teeth were also significantly associated with dental pain. Conclusions Our findings suggest that contextual and individual social capital are independently associated with dental pain. PMID:23289932

  1. Social capital and dental pain in Brazilian northeast: a multilevel cross-sectional study.

    PubMed

    Santiago, Bianca Marques; Valença, Ana Maria Gondim; Vettore, Mario Vianna

    2013-01-04

    There is limited evidence on possible associations between social determinants and dental pain. This study investigated the relationship of neighborhood and individual social capital with dental pain in adolescents, adults and the elderly. A population-based multilevel study was conducted involving 624 subjects from 3 age groups: 15-19, 35-44 and 65-74 years. They were randomly selected from 30 census tracts in three cities in the State of Paraíba, Brazil. A two-stage cluster sampling was used considering census tracts and households as sampling units. The outcome of study was the presence of dental pain in the last 6 months. Information on dental pain, demographic, socio-economic, health-related behaviors, use of dental services, self-perceived oral health and social capital measures was collected through interviews. Participants underwent a clinical examination for assessment of dental caries. Neighborhood social capital was evaluated using aggregated measures of social trust, social control, empowerment, political efficacy and neighborhood safety. Individual social capital assessment included bonding and bridging social capital. Multilevel logistic regression was used to test the relationship of neighborhood and individual social capital with dental pain after sequential adjustment for covariates. Individuals living in neighborhoods with high social capital were 52% less likely to report dental pain than those living in neighborhoods with low social capital (OR = 0.48, 95% CI = 0.27-0.85). Bonding social capital (positive interaction) was independently associated with dental pain (OR = 0.88, 95% CI = 0.80-0.91). Last dental visit, self-perceived oral health and number of decayed teeth were also significantly associated with dental pain. Our findings suggest that contextual and individual social capital are independently associated with dental pain.

  2. [Double aortic arch with dominant left arch: case report].

    PubMed

    Ece, Ibrahim; Paç, Feyza Ayşenur; Paç, Mustafa; Ballı, Sevket

    2012-09-01

    A vascular ring is defined as an anomaly of the great arteries (aortic arch and its branches) that compresses the trachea or esophagus. Double aortic arch is the most common vascular ring. Double aortic arch is very rare and typically becomes symptomatic in infancy or early childhood. We present a 7-year-old girl admitted to our clinic for evaluation of recurrent respiratory infection with dysphagia. Double aortic arch was suspected from echocardiography and diagnosed with cardiac computed tomography. Left aortic arcus was larger than the right at computed tomography and cardiac catheterisation. After surgery the symptoms improved strikingly. We conclude that vascular ring should be considered in the patients presenting with recurrent pulmonary infections and dysphagia. Early diagnosis and treatment may prevent chronic, irreversible complications.

  3. Incisor and molar overjet, arch contraction, and molar relationship in the mixed dentition in repaired complete unilateral cleft lip and palate: A qualitative and quantitative appraisal.

    PubMed

    Disthaporn, Suteeta; Suri, Sunjay; Ross, Bruce; Tompson, Bryan; Baena, Diogenes; Fisher, David; Lou, Wendy

    2017-07-01

    To compare the mixed dentition incisor and molar overjet, severity of contraction of the dental arch, and the sagittal molar relationship on the cleft side vs the noncleft side in children with repaired complete unilateral cleft of the lip and palate (UCLP). Orthodontic records taken prior to orthodontic preparation for alveolar bone grafting were screened to select study casts from patients with nonsyndromic repaired complete UCLP who did not have mandibular skeletal or dental asymmetry. The study sample comprised dental casts from 74 children aged 8.9 ± 1 years. Standardized digital photographs were acquired at 1:1 magnification. A coordinate system was developed using digital image-processing software (Photoshop CS4 and Adobe Illustrator). Incisor and molar overjet, Angle's classification, and arch contraction were recorded. Descriptive statistics, paired t-tests, and kappa statistics were used to compare the cleft and noncleft sides. A negative overjet of -1 to -5 mm was often present at the incisors, with greater frequency and magnitude on the cleft side. Class II molar relation was more frequent on the cleft side (61.1%) than on the noncleft side (47.2%). Significantly greater contraction of the cleft side deciduous canine and deciduous first molar was noted, while the difference was very minor at the first permanent molar. Cleft side maxillary arch contraction was most severe in the deciduous canine and first deciduous molar region and progressively less severe in the posterior region of the arch. A greater frequency and severity of negative overjet and Class II molar relationship was seen on the cleft side.

  4. Predictors of Dental Care Use: Findings from the National Longitudinal Study of Adolescent Health

    PubMed Central

    Okunseri, Christopher; Okunseri, Elaye; Garcia, Raul I.; Visotcky, Alexis (Dye); Szabo, Aniko

    2013-01-01

    Objective To examine longitudinal trends and associated factors in dental service utilization by adolescents progressing to early adulthood in the United States. Data Source The National Longitudinal Study of Adolescent Health from Waves I (1994-95), II (1996), III (2001-2002) and IV (2007-2008). Study Design This is a retrospective, observational study of adolescents' transition to early adulthood. We obtained descriptive statistics and performed logistic regression analyses to identify the effects of baseline and concurrent covariates on dental service utilization from adolescence to early adulthood over time. Principal Findings Dental service utilization within the prior 12 months peaked at age 16 (72%), gradually decreased until age 21 (57%), and thereafter remained flat. Whites and Asians had a 10-20 percentage points higher proportion of dental service utilization at most ages compared to Blacks and Hispanics. Dental service utilization at later follow-up visits was strongly associated with baseline utilization with OR= 10.7, 2.4 and 1.5 at the 1-year, 7-year and 13-year follow-ups respectively. These effects decreased when adjusted for current income, insurance and education. Compared to Whites, Blacks were consistently less likely to report any dental examination. Conclusion Dental service utilization was highest in adolescents. Gender, education, health insurance and income in young adulthood were significant predictors of reporting a dental examination. Blacks had lower odds of reporting a dental examination either as adolescents or as young adults. PMID:23850156

  5. Association Between Dental Students' Emotional Intelligence and Academic Performance: A Study at Six Dental Colleges in India.

    PubMed

    Kumar, Amit; Puranik, Manjunath P; Sowmya, K R

    2016-05-01

    Since the role of emotional intelligence (EI) in achieving academic excellence requires further research, the aims of this cross-sectional study were to assess EI and its associated factors and to determine any association between EI and academic performance among final-year dental students in Bengaluru, India. In 2015, 208 dental students from six dental colleges in Bengaluru were invited to participate in the study. Their demographic and lifestyle data were collected, and EI was assessed with the 30-item Emotional Quotient Self-Assessment Checklist developed by Sterrett. Academic performance was assessed using grades obtained in the final-year undergraduate examination. The response rate was 96% (N=200). Overall, 54.5% of the participants had high EI scores (≥120), although only 51 (25.5%) had a high EI score in all the domains (≥20). EI was significantly greater in females than males. Gender, sleep, meeting friends, physical exercise, recreational activities, and academic performance were significantly associated with EI and accounted for 42% variance in hierarchical regression analysis. EI was also positively associated with academic performance. Gender and healthy lifestyle habits were positively associated with EI, which in turn influenced these students' academic performance. These findings suggest a possible need for attention to developing dental students' EI.

  6. Variation in Formation of Superficial Palmar Arches with Clinical Implications

    PubMed Central

    Vatsalaswamy, P.; Bahetee, B.H.

    2014-01-01

    Background: Knowledge of the variations in the arterial supply of hand has reached a point of practical importance with the advent of microvascular surgery for revascularization, replantation and composite tissue transfers. Arterial supply of hand is derived from two anastomotic arches, formed between two main arteries of forearm i.e. radial, ulnar and their branches, in the palm. Objective: The superficial palmar arch shows variation in formation at the radial side. In the present study we have recorded its data which would help in its clinical and surgical implications. Material and Methods: In the present study we have studied the formation of superficial palmar arches and their variations in 100 cadaveric hands at Dr. D . Y. Patil Medical College, Pune and B.J. Government Medical College, Pune, India. Result and Conclusion: According to Adachi’s classification the most predominant pattern obseved was of Ulnar type arch (66%). According to Coleman and Anson classification 82% showed complete (Group I) superficial palmar arches and a very low incidence (18%) of incomplete arches (Group II). This suggests that collateral circulation is present in majority of cases. This would result in least number of complications considering radial artery harvesting for coronary bypass. Sub-classification of arches according to Coleman and Anson 1961 indicates that the predominant type in the present study was of Group I (Type B) which is formed entirely by Ulnar Artery (56%). Median artery and ulnar artery forming an incomplete superficial arch under Group II (Type C) having an incidence of 4% was recorded. Thus in such cases radial artery harvesting for coronary artery bypass may prove to be less fatal. This study is an effort to provide data about the formation of superficial palmar arches which has been a centre of attraction for most of the surgical procedures and injuries of the hand. PMID:24959427

  7. Retention of fissure sealants in young permanent molars affected by dental fluorosis: a 12-month clinical study.

    PubMed

    Hasanuddin, S; Reddy, E R; Manjula, M; Srilaxmi, N; Rani, S T; Rajesh, A

    2014-10-01

    To evaluate and compare retention and caries occurance following placement of Clinpro and FUJI VII fissure sealants, by two different techniques simultaneously in unsealed, contralateral young permanent molars of 7- to 10-year-old children affected by mild to moderate dental fluorosis at various recall intervals of 1 week, 1, 3, 6 and 12 months. 80 schoolchildren with mild to moderate dental fluorosis were assigned to Group A and Group B with 40 children in each group. In Group A Clinpro fissure sealant and in Group B Fuji VII fissure sealant was used. In both the groups fissure sealants were applied by conventional fissure sealant technique (CST) on one side and enameloplasty sealant technique (EST) on the other side of the same arch. The applied fissure sealants were evaluated clinically for retention and caries incidence. Clinpro fissure sealant showed a retention rate of 95% when compared with Fuji VII (57.5%) at the end of 12 months, which was statistically significant. Regarding techniques, EST showed better results than CST in both the groups. Comparison of groups with respect to retention and techniques at different time periods was performed using Mann-Whitney U test (p < 0.05). Comparison of different time periods with respect to retention and technique in all the groups was performed using Wilcoxon matched pairs test by ranks (p < 0.05). Clinpro fissure sealant showed better retention at all treatment intervals, when compared with Fuji VII. Further follow-up is required to study the efficacy of the fissure sealant placement techniques.

  8. Finite Element Analysis Generates an Increasing Interest in Dental Research: A Bibliometric Study

    PubMed Central

    Diarra, Abdoulaziz; Mushegyan, Vagan; Naveau, Adrien

    2016-01-01

    Purpose: The purpose was to provide a longitudinal overview of published studies that use finite element analysis in dental research, by using the SCI-expanded database of Web of Science® (Thomson Reuters). Material and Methods: Eighty publications from 1999-2000 and 473 from 2009-2010 were retrieved. This literature grew faster than the overall dental literature. The number of publishing countries doubled. The main journals were American or English, and dealt with implantology. For the top 10 journals publishing dental finite element papers, the mean impact factor increased by 75% during the decade. Results: Finite elements generate an increasing interest from dental authors and publishers worldwide. PMID:27006722

  9. Improving dental experiences by using virtual reality distraction: a simulation study.

    PubMed

    Tanja-Dijkstra, Karin; Pahl, Sabine; White, Mathew P; Andrade, Jackie; Qian, Cheng; Bruce, Malcolm; May, Jon; Moles, David R

    2014-01-01

    Dental anxiety creates significant problems for both patients and the dental profession. Some distraction interventions are already used by healthcare professionals to help patients cope with unpleasant procedures. The present study is novel because it a) builds on evidence that natural scenery is beneficial for patients, and b) uses a Virtual Reality (VR) representation of nature to distract participants. Extending previous work that has investigated pain and anxiety during treatment, c) we also consider the longer term effects in terms of more positive memories of the treatment, building on a cognitive theory of memory (Elaborated Intrusions). Participants (n = 69) took part in a simulated dental experience and were randomly assigned to one of three VR conditions (active vs. passive vs. control). In addition, participants were distinguished into high and low dentally anxious according to a median split resulting in a 3×2 between-subjects design. VR distraction in a simulated dental context affected memories a week later. The VR distraction had effects not only on concurrent experiences, such as perceived control, but longitudinally upon the vividness of memories after the dental experience had ended. Participants with higher dental anxiety (for whom the dental procedures were presumably more aversive) showed a greater reduction in memory vividness than lower dental-anxiety participants. This study thus suggests that VR distractions can be considered as a relevant intervention for cycles of care in which people's previous experiences affect their behaviour for future events.

  10. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

    PubMed Central

    Daas, M.; Assaf, A.; Dada, K.; Makzoumé, J.

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible) with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months). Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years. PMID:26064119

  11. Improving Dental Experiences by Using Virtual Reality Distraction: A Simulation Study

    PubMed Central

    Tanja-Dijkstra, Karin; Pahl, Sabine; P. White, Mathew; Andrade, Jackie; Qian, Cheng; Bruce, Malcolm; May, Jon; Moles, David R.

    2014-01-01

    Dental anxiety creates significant problems for both patients and the dental profession. Some distraction interventions are already used by healthcare professionals to help patients cope with unpleasant procedures. The present study is novel because it a) builds on evidence that natural scenery is beneficial for patients, and b) uses a Virtual Reality (VR) representation of nature to distract participants. Extending previous work that has investigated pain and anxiety during treatment, c) we also consider the longer term effects in terms of more positive memories of the treatment, building on a cognitive theory of memory (Elaborated Intrusions). Participants (n = 69) took part in a simulated dental experience and were randomly assigned to one of three VR conditions (active vs. passive vs. control). In addition, participants were distinguished into high and low dentally anxious according to a median split resulting in a 3×2 between-subjects design. VR distraction in a simulated dental context affected memories a week later. The VR distraction had effects not only on concurrent experiences, such as perceived control, but longitudinally upon the vividness of memories after the dental experience had ended. Participants with higher dental anxiety (for whom the dental procedures were presumably more aversive) showed a greater reduction in memory vividness than lower dental-anxiety participants. This study thus suggests that VR distractions can be considered as a relevant intervention for cycles of care in which people’s previous experiences affect their behaviour for future events. PMID:24621518

  12. Lucy's Flat Feet: The Relationship between the Ankle and Rearfoot Arching in Early Hominins

    PubMed Central

    2010-01-01

    Background In the Plio-Pleistocene, the hominin foot evolved from a grasping appendage to a stiff, propulsive lever. Central to this transition was the development of the longitudinal arch, a structure that helps store elastic energy and stiffen the foot during bipedal locomotion. Direct evidence for arch evolution, however, has been somewhat elusive given the failure of soft-tissue to fossilize. Paleoanthropologists have relied on footprints and bony correlates of arch development, though little consensus has emerged as to when the arch evolved. Methodology/Principal Findings Here, we present evidence from radiographs of modern humans (n = 261) that the set of the distal tibia in the sagittal plane, henceforth referred to as the tibial arch angle, is related to rearfoot arching. Non-human primates have a posteriorly directed tibial arch angle, while most humans have an anteriorly directed tibial arch angle. Those humans with a posteriorly directed tibial arch angle (8%) have significantly lower talocalcaneal and talar declination angles, both measures of an asymptomatic flatfoot. Application of these results to the hominin fossil record reveals that a well developed rearfoot arch had evolved in Australopithecus afarensis. However, as in humans today, Australopithecus populations exhibited individual variation in foot morphology and arch development, and “Lucy” (A.L. 288-1), a 3.18 Myr-old female Australopithecus, likely possessed asymptomatic flat feet. Additional distal tibiae from the Plio-Pleistocene show variation in tibial arch angles, including two early Homo tibiae that also have slightly posteriorly directed tibial arch angles. Conclusions/Significance This study finds that the rearfoot arch was present in the genus Australopithecus. However, the female Australopithecus afarensis “Lucy” has an ankle morphology consistent with non-pathological flat-footedness. This study suggests that, as in humans today, there was variation in arch development

  13. Dental pain and associated factors among pregnant women: an observational study.

    PubMed

    Krüger, Marta S M; Lang, Celina A; Almeida, Luiza H S; Bello-Corrêa, Fernanda O; Romano, Ana R; Pappen, Fernanda G

    2015-03-01

    The present study aimed to determine the prevalence of dental pain during pregnancy and its association with sociodemographic factors and oral health conditions among 315 pregnant women in South Brazil. Participants were interviewed to obtain sociodemographic data, such as age, educational level, employment status, family income, and marital and parity status. Medical and dental histories were also collected, including the occurrence of dental pain and the use of dental services during pregnancy. Clinical examinations were performed to assess the presence of visible plaque and gingival bleeding and to calculate the decayed, missing, and filled teeth index. Means and standard deviations of continuous variables and frequencies and percentages of categorical variables were calculated. Independent variables were included in a multivariate logistic regression analysis. A total of 173 (54.9 %) pregnant women reported dental pain during pregnancy. After adjustment of the analysis, caries activity remained the main determinant of dental pain (odds ratio 3.33, 95 % CI 1.67-6.65). The prevalence of dental pain during pregnancy was high and the presence of caries activity was a determinant of dental pain. Moreover, access to oral health care was low, despite pregnant women's increased need for dental assistance.

  14. A knowledge, attitude, and practices study regarding dental floss among dentists in India.

    PubMed

    Madan, Charu; Arora, Kapil; Chadha, Vandana Srikrishna; Manjunath, Bhadravathi Chaluvaiah; Chandrashekar, Byalakere Rudraiah; Rama Moorthy, Vatchala Rani

    2014-05-01

    To assess the knowledge, attitude, self-reported practices, and prescription patterns regarding dental floss amongst a select population of dentists in India. A pretested 30-item questionnaire was self-administered by authors to the dental faculty and postgraduate students in dental schools in Delhi-National Capital Region (NCR). Nine dental institutes were selected by simple random sampling procedure among 15 institutions and a total of 255 dentists were included in the study. The data obtained were analyzed by SPSS version 18. Descriptive statistics such as frequencies were calculated and Pearson's Chi-square test was used with P value fixed at 0.05. There was lack of adequate knowledge regarding dental floss, among dentists in India. 78% of the dentists responded that the routine use of dental floss was necessary for good periodontal health. Majority of the dentists cited lack of awareness, availability, and cost as the major factors affecting floss usage. Lack of training in the dental education programs may have an impact on the prescription patterns as well. 15.3% of those surveyed do not use floss at all. 63.9% of the dentists prescribed floss routinely to their patients and considered factors like education, occupation, and socioeconomic status of the patient before prescribing dental floss. Health education programs regarding dental floss are necessary to create awareness among the general population and adequate training at undergraduate level is also essential to increase the prescription practices. Dentists should practice recommended oral self-care and act as role models.

  15. Implant-Supported Immediately Loaded Full-Arch Rehabilitations: Comparison of Resin and Zirconia Clinical Outcomes in a 5-Year Retrospective Follow-Up Study.

    PubMed

    Tartaglia, Gianluca Martino; Maiorana, Carlo; Gallo, Maria; Codari, Marina; Sforza, Chiarella

    2016-02-01

    We analyzed complications and failures of final full-arch implant-supported rehabilitations, comparing resin and zirconia prosthesis materials. Prostheses were retrospectively followed up for 5 years. One hundred twenty-five patients who received one or two four to six implant-supported immediately loaded full-arch rehabilitations in resin (166 prostheses) or zirconia (48 prostheses) were analyzed. One hundred thirteen patients (53 men, 60 women), with 214 full-arch prostheses (105 maxillary, 109 mandibular), were analyzed. During the follow-up interval, the prosthesis annual complication rate was 6.6%, free complications survival was 75.5% (60 months). Age, number of implants, and prosthesis material did not influence complication risk. Men had a higher risk of complications than women. Prosthesis annual failure rate was 4.6%, free survival was 85.5% (60 months). Age, number of implants, and prosthesis material did not influence failure risk. Men and maxillary arch prostheses had a higher risk of failures than women and mandibular arch prostheses. Implant-supported, immediately loaded full-arch rehabilitations supporting resin or zirconia based prostheses were clinically successful in a 5-year follow-up. Prosthesis material did not influence complication risk.

  16. A Study of Radiographic Imaging Systems Used for Dental Hygiene.

    ERIC Educational Resources Information Center

    Karst, Nancy S.

    Thirty-three two-year dental hygiene programs throughout the United States were surveyed to identify the radiographic imaging system most often used and the accompanying rationale for that decision. A literature review identified the three radiographic imaging systems most frequently used and indicated that all dental hygiene programs had the…

  17. A Study of Radiographic Imaging Systems Used for Dental Hygiene.

    ERIC Educational Resources Information Center

    Karst, Nancy S.

    Thirty-three two-year dental hygiene programs throughout the United States were surveyed to identify the radiographic imaging system most often used and the accompanying rationale for that decision. A literature review identified the three radiographic imaging systems most frequently used and indicated that all dental hygiene programs had the…

  18. Biology and cytotoxicity of dental materials: an in vitro study.

    PubMed

    Gociu, M; Pătroi, D; Prejmerean, Cristina; Păstrăv, O; Boboia, Stanca; Prodan, Doina; Moldovan, Marioara

    2013-01-01

    The purpose of the experiment was to determine the degree of biocompatibility of a sealer (RO, laboratory made product) dental material in terms of cytotoxicity and animal tests. In the present study, the biological compatibility of eight experimental composite materials was examined by in vitro methods. The bio-composites used for the cytotoxicity test were placed into direct contact with normal human fibroblasts in a cell-culture dish. After fibroblast bioassay was performed, a duplicate sample of biomaterial was placed in each well, and then the fibroblasts were incubated for 48 hours at 37°C and 5% carbon dioxide. Local reactions after the implantation of the material regarding preclinical evaluation have been carried out within the Biobase Laboratory of the "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania. The biocompatibility was studied using the tolerance test by the subcutaneous and intramuscular implantation of the cured specimens. The sealant C3 scored the highest value to the cell viability. The results of the present study showed that different dental materials had different effects on cells. The resin monomer TEGDMA, present in the sealer's composition, increased the amount of intracellular reactive oxygen species. Resin-based composites are cytotoxic before polymerization and immediately thereafter, whereas already set specimens cause almost no reaction. The test of tolerance showed that the composite materials do not contain any toxic, irritant substances or destructive ones for the living cells or tissues. The tests with experimental composite materials revealed that they are not cytotoxic for the living cells, in all versions of the materials used. All the samples of composite materials have maintained their integrity during the experiment, allowing the testing together with the embedded cells, which proved good viability, so they are suitable for dentistry use.

  19. A longitudinal study of dental health from the age of 14 to 41.

    PubMed

    Crossner, Claes-Göran; Unell, Lennart

    2007-01-01

    The aim of present study was to longitudinally follow dental health from the age of 14 to 41. Originally an entire age group attending one of the compulsory schools in the city of Orebro, Sweden was selected and 115 children born in 1962 were included in the study. At the last examination 27 years later, 73 (63%) individuals, 35 males and 38 females, could still be located and were willing to participate. The drop out analysis did not show any statistical difference between the drop-outs and this final material. All participants had experienced a comprehensive whole population based preventive dental care, free of charge, during the first 19 years of their lives, and after that the increment of dental diseases had been limited. Only two individuals were diagnosed with chronic periodontitis at 41, and 70% of all DMFS registered at 41 were present already at 19. This positive development during adulthood seemed to be unrelated to socio-economic status. In addition, the dental health at 41 did not seem to be obviously influenced by if the participants, as adults, had paid yearly visits to the dentist or not, and there was no evidence supporting that regularly seeing a dental hygienist or using daily inter-dental cleaning would improve dental health. The most obvious difference in dental health at 41 was due to gender where e.g. the experience of proximal caries and bleeding after probing were twice as frequent in males as in females. Based on the results of the present study it can be concluded that uncritically abandoning whole population preventive strategies might not be in the best interest of public dental health. Furthermore, if already existing dental care resources should be reallocated for a better long-term dental health investment it should be on the expense of the young adults to the benefit of the young teenagers (as population sub-groups) and not the other way around based on individual indications.

  20. 1. VIEW SOUTHWARD FROM SOUTHWEST CORNER FRONT AND ARCH STREETS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW SOUTHWARD FROM SOUTHWEST CORNER FRONT AND ARCH STREETS (2. N. Front Street starts at left) - North Front Street Area Study, 2-66 North Front Street (Commercial Buildings), Philadelphia, Philadelphia County, PA

  1. Follow-Up Study of 1990 Dental Hygiene Graduates. Volume XX, No. 1.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In a continuing effort to measure the quality of their Dental Hygiene program, explore the need for changes, and substantiate the program's goals for accreditation standards, a follow-up study was conducted of the 1990 Dental Hygiene program graduates from William Rainey Harper (WRHC) College in Palatine, Illinois. A survey was mailed to all 30…

  2. Follow-Up Study of 1989 Dental Hygiene Graduates. Volume XIX, No. 2.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In a continuing effort to measure the quality of their Dental Hygiene program, explore the need for changes, and substantiate the program's goals for accreditation standards, a follow-up study was conducted of the 1989 Dental Hygiene program graduates from William Rainey Harper College (WRHC). A survey was mailed to all 29 associate degree…

  3. Follow-Up Study of 1991 Dental Hygiene Graduates. Volume XXI, No. 4.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In a continuing effort to measure the quality of their Dental Hygiene program, explore the need for changes, and substantiate the program's goals for accreditation standards, a follow-up study was conducted of the 1991 Dental Hygiene program graduates from William Rainey Harper College (WRHC) in Palatine, Illinois. Surveys were mailed to all 28…

  4. Follow-Up Study of 1992 Dental Hygiene Graduates. Volume XXII, No. 2.

    ERIC Educational Resources Information Center

    Holt, Marianne; Lucas, John A.

    In a continuing effort to measure the quality of their Dental Hygiene program, explore the need for changes, and substantiate the program's goals for accreditation standards, a follow-up study was conducted of the 1992 Dental Hygiene program graduates from William Rainey Harper College (WRHC) in Palatine, Illinois. Surveys were mailed to all 29…

  5. Follow-Up Study of 1987 Dental Hygiene Graduates. Volume XVII, No. 2.

    ERIC Educational Resources Information Center

    Holt, Marianne; Flaherty, Toni

    In 1988, a follow-up study was performed of the 1987 graduates of the Dental Hygiene program of William Rainey Harper College (WRHC), in Illinois, in order to determine the quality of the program and the need for changes, and to substantiate the program's goals for accreditation standards. A survey was mailed to all of the 1987 dental hygiene…

  6. Impact of Curriculum on Understanding of Professional Practice: A Longitudinal Study of Students Commencing Dental Education

    ERIC Educational Resources Information Center

    Kieser, Jules A.; Dall'Alba, Gloria; Livingstone, Vicki

    2009-01-01

    This longitudinal study examines changes in understanding of dental practice among a cohort of students in the early years of a dentistry programme. In their first two professional years, we identified five distinct understandings of dental practice that we have ordered from least to most comprehensive: "relieving pain or generally caring for…

  7. Impact of Curriculum on Understanding of Professional Practice: A Longitudinal Study of Students Commencing Dental Education

    ERIC Educational Resources Information Center

    Kieser, Jules A.; Dall'Alba, Gloria; Livingstone, Vicki

    2009-01-01

    This longitudinal study examines changes in understanding of dental practice among a cohort of students in the early years of a dentistry programme. In their first two professional years, we identified five distinct understandings of dental practice that we have ordered from least to most comprehensive: "relieving pain or generally caring for…

  8. The Effects of Patient Contact upon First-Year Dental Students: A Study of Changing Perceptions.

    ERIC Educational Resources Information Center

    Branch, Roger G.; And Others

    This study attempted to determine the effects of early patient contact through clinic experience upon the perceptions and attitudes of first year dental students. Questionnaires were administered at the beginning and end of students' first year in an innovative and new dental school where they were introduced to clinic experience within the first…

  9. Methodological Study for Determining the Task Content of Dental Auxiliary Education Programs. Progress Report.

    ERIC Educational Resources Information Center

    Terry, David R.

    The purpose of the study was to develop a methodology of collecting data pertaining to the dental tasks taught and the responsibility levels to which they are taught in the curricula of educational institutions preparing dental assistants, hygienists, and laboratory technicians. The sample group consisted of Faculty and Preceptor respondents from…

  10. Peri-implant bone loss of dental implants with platform-switching design after 5 years of loading: a cross-sectional study.

    PubMed

    Joda, Tim; Michelaki, Ioanna; Heydecke, Guido

    2015-01-01

    The aim of this cross-sectional study was to estimate bone loss of implants with platform-switching design and analyze possible risk indicators after 5 years of loading in a multi-centered private practice network. Peri-implant bone loss was measured radiographically as the distance from the implant shoulder to the mesial and distal alveolar crest, respectively. Risk factor analysis for marginal bone loss included type of implant prosthetic treatment concept and dental status of the opposite arch. A total of 316 implants in 98 study patients after 5 years of loading were examined. The overall mean value for radiographic bone loss was 1.02 mm (SD ± 1.25 mm, 95% CI 0.90- 1.14). Correlation analyses indicated a strong association of peri-implant bone loss > 2 mm for removable implant-retained prostheses with an odds ratio of 53.8. The 5-year-results of the study show clinically acceptable values of mean bone loss after 5 years of loading. Implant-supported removable prostheses seem to be a strong co-factor for extensive bone level changes compared to fixed reconstructions. However, these results have to be considered for evaluation of the included special cohort under private dental office conditions.

  11. 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

  12. Topics of internal medicine for undergraduate dental education: a qualitative study.

    PubMed

    Kunde, A; Harendza, S

    2015-08-01

    Due to the ageing population, internal medicine has become increasingly important for dental education. Although several studies have reported dentists' dissatisfaction with their internal medicine training, no guidelines exist for internal medicine learning objectives in dental education. The aim of this study was to identify topics of internal medicine considered to be relevant for dental education by dentists and internists. Eight dentists from private dental practices in Hamburg and eight experienced internal medicine consultants from Hamburg University Hospital were recruited for semi-structured interviews about internal medicine topics relevant for dentists. Internal diseases were clustered into representative subspecialties. Dentists and internists were also asked to rate medical diseases or emergencies compiled from the literature by their relevance to dental education. Coagulopathy and endocarditis were rated highest by dentists, whilst anaphylaxis was rated highest by internists. Dentists rated hepatitis, HIV, organ transplantation and head/neck neoplasm significantly higher than internists. The largest number of different internal diseases mentioned by dentists or internists could be clustered under cardiovascular diseases. The number of specific diseases dentists considered to be relevant for dental education was higher in the subspecialties cardiovascular diseases, haematology/oncology and infectiology. We identified the internal medicine topics most relevant for dental education by surveying practising dentists and internists. The relevance of these topics should be confirmed by larger quantitative studies to develop guidelines how to design specific learning objectives for internal medicine in the dental curriculum. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. [Perceived oral health and use of dental services during pregnancy: the MaterniDent study].

    PubMed

    Vergnes, Jean-Noel; Pastor-Harper, Diana; Constantin, Delia; Bedos, Christophe; Kaminski, Monique; Nabet, Cathy; Sixou, Michel; Rouillon, F

    2013-01-01

    The main objective of the MaterniDent study was to determine the nature and frequency of dental problems experienced by pregnant women and their associated factors. The secondary objective was to determine the frequency of dental visits during pregnancy and to identify associated factors. The MaterniDent study was a multicenter cross-sectional study conducted among 904 postpartum women in three French maternity wards. Data were collected using self-administered questionnaires. Measured variables included socio-demographic, health and behavioral characteristics. 57% of women reported having experienced at least one dental problem during pregnancy, while 20% had experienced dental pain during pregnancy. Multiparity, vomiting, soda consumption and increased sugar consumption during pregnancy were significantly associated with dental pain (p<0.05). 56% of women did not visit a dentist during pregnancy, 26% consulted a dentist for a perceived problem, and 18% visited a dentist for a check-up. Younger pregnant women and those without supplemental insurance were less likely to see a dentist for a preventive dental visit (p <0.05). A significant proportion of women experienced a dental problem during pregnancy, although they did not necessarily consult a dentist to treat the problem. Given the impact of oral diseases for both mother and child, prevention and professional dental care during pregnancy should be promoted.

  14. Arch length considerations due to the curve of Spee: a mathematical model.

    PubMed

    Germane, N; Staggers, J A; Rubenstein, L; Revere, J T

    1992-09-01

    Arch length analysis should consider discrepancies not only within the sagittal plane but also within the vertical and transverse planes. The vertical deviation of the occlusal plane from a flat plane is known as the curve of Spee. The purpose of this study was to produce a mathematical model of the mandibular arch form in three planes of space and to determine the effect that the curve of Spee has on arch circumference. Two mandibular arch forms, the catenary and the Bonwill-Hawley, were examined. The curve of Spee was modeled as a cylinder perpendicular to the midsagittal plane centered on the arch anteroposteriorly. A mathematical distance formula was used to calculate arch circumferences from the central fossa of the first molars for 10 arches with curves of Spee ranging from 0 to 10 mm. This procedure was repeated for arch circumferences extending from the central fossa of the second molars. Plots for the difference in arch circumferences verses depth of the curve of Spee showed that the relationship between these two variables is not linear and is less than one to one. This model showed that clinical practice of allowing 1 mm of arch circumference for leveling each millimeter of curve of Spee overestimates the amount of arch circumference needed to flatten the curve of Spee.

  15. 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.

  16. Characteristics of dental fear among Arabic-speaking children: a descriptive study.

    PubMed

    El-Housseiny, Azza A; Alamoudi, Najlaa M; Farsi, Najat M; El Derwi, Douaa A

    2014-09-22

    Dental fear has not only been linked to poor dental health in children but also persists across the lifespan, if unaddressed, and can continue to affect oral, systemic, and psychological health. The aim of this study was to assess the factor structure of the Arabic version of the Children's Fear Survey Schedule-Dental Subscale (CFSS-DS), and to assess the difference in factor structure between boys and girls. Participants were 220 consecutive paediatric dental patients 6-12 years old seeking dental care at the Faculty of Dentistry, King Abdulaziz University, Saudi Arabia. Participants completed the 15-item Arabic version of the CFSS-DS questionnaire at the end of the visit. Internal consistency was assessed using Cronbach's alpha. Factor analysis (principal components, varimax rotation) was employed to assess the factor structure of the scale. The Cronbach's alpha was 0.86. Four factors with eigenvalues above 1.00 were identified, which collectively explained 64.45% of the variance. These factors were as follows: Factor 1, 'fear of usual dental procedures' consisted of 8 items such as 'drilling' and 'having to open the mouth', Factor 2, 'fear of health care personnel and injections' consisted of three items, Factor 3, 'fear of strangers', consisted of 2 items. Factor 4, 'fear of general medical aspects of treatment', consisted of 2 items. Notably, four factors of dental fear were found in girls, while five were found in boys. Four factors of different strength pertaining to dental fear were identified in Arabic-speaking children, indicating a simple structure. Most items loaded high on the factor related to fear of usual dental procedures. The fear-provoking aspects of dental procedures differed in boys and girls. Use of the scale may enable dentists to determine the item/s of dental treatment that a given child finds most fear-provoking and guide the child's behaviour accordingly.

  17. Dental Occlusion and Ophthalmology: A Literature Review

    PubMed Central

    Marchili, Nicola; Ortu, Eleonora; Pietropaoli, Davide; Cattaneo, Ruggero; Monaco, Annalisa

    2016-01-01

    Stomatognathic system is strictly correlated to other anatomical regions; many studies investigated relationship between temporomandibular joint and posture, several articles describe cranio-facial pain from dental causes, such as trigger points. Until now less interest has been given to connections between dental occlusion and ophthalmology, even if they are important and involving. Clinical experience in dental practice claims that mandibular latero-deviation is connected both to eye dominance and to defects of ocular convergence. The trigeminal nerve is the largest and most complex of the twelve cranial nerves. The trigeminal system represents the connection between somitic structures and those derived from the branchial arches, collecting the proprioception from both somitic structures and oculomotor muscles. The intermedius nucleus of the medulla is a small perihypoglossal brainstem nucleus, which acts to integrate information from the head and neck and relays it on to the nucleus of the solitary tract where autonomic responses are generated. This intriguing neurophysiological web led our research group to investigate anatomical and functional associations between dental occlusion and vision. In conclusion, nervous system and functional pathways strictly connect vision and dental occlusion, and in the future both dentists and oculists should be more and more aware of this correlation for a better diagnosis and therapy. PMID:27733873

  18. Clinical implication of blood glucose monitoring in general dental offices: the Ehime Dental Diabetes Study

    PubMed Central

    Harase, Tadahiro; Nishida, Wataru; Hamakawa, Tomohiro; Hino, Satoshi; Shigematsu, Kenji; Kobayashi, Satoru; Sako, Hirofumi; Ito, Shirou; Murakami, Hajime; Nishida, Kei; Inoue, Hiroshi; Fujisawa, Masahito; Yoshizu, Hiroshi; Kawamura, Ryoichi; Takata, Yasunori; Onuma, Hiroshi; Shimizu, Keita; Hamakawa, Hiroyuki; Osawa, Haruhiko

    2015-01-01

    Objective We examined whether general dentists can contribute to the detection of patients with undiagnosed diabetes and prediabetes by monitoring blood glucose in dental clinics. Research design and methods A total of 716 patients who visited clinics for dental treatment were enrolled and classified into 3 groups (mild, moderate, and severe) according to Kornman's criteria for periodontitis. The correlations between the casual blood glucose level, presence or absence of the history of diabetes, and/or severity of periodontitis were evaluated. Results 68 patients (9.5%) had hyperglycemia (blood glucose ≥200 mg/dL). Of these patients, 20 (29.4%) did not have a history of diabetes. Blood glucose tended to be higher with greater periodontitis severity. Of the 3 groups, the severe periodontitis group had the highest proportion of patients with hyperglycemia (p<0.0001). Conclusions Patients with dental problems could be screened for diabetes, especially undiagnosed diabetes. General dentists could function as practitioners to screen for diabetes. Trial registration number UMIN-CTR 000014877. PMID:26629348

  19. Digital radiological research in forensic dental investigation: case studies.

    PubMed

    Nuzzolese, E; Di Vella, G

    2012-04-01

    The advent of dental digital radiology and new portable X-ray devices allows the execution of periapical X-ray images not only in the dental surgery but also in hitherto difficult locations such as field military hospitals, archaeological excavation sites, morgues and in cases of house arrest. In this work authors evaluated the feasibility of Nomad Examiner (Aribex inc.) handheld X-ray device combined with a digital sensor and a portable pc in forensic odontology applications. Employed for the first time forensically during the 2004 Tsunami victim identification process, the Nomad Examiner has now passed all security and conformity requirements of US and EU regulations. Examples of the practical use and the technical features of this device are seen when employed in odontological assessment of skeletonised and carbonized individuals and the assessment of individuals under house arrest complaining dental lesions. Results from the use this portable device demonstrate the benefits of a dental radiological assessment during an autopsy with the aim of human identification and the importance of a complete dental assessment (clinical and radiological) when evaluating dental traumatic lesions of individuals who cannot visit a dental surgery. In the first example forensic dentist would work alongside a forensic pathologist. On the other hand in the second example an odontologist - dentist could be appointed as an expert witness directly by a Court.

  20. Palatal positioned implants in severely atrophic maxillae versus conventional implants to support fixed full-arch prostheses: Controlled retrospective study with 5 years of follow-up.

    PubMed

    Candel-Marti, Eugenia; Peñarrocha-Oltra, David; Bagán, Leticia; Peñarrocha-Diago, Maria; Peñarrocha-Diago, Miguel

    2015-05-01

    To evaluate soft tissue conditions and bone loss around palatal positioned implants supporting fixed full-arch prostheses to rehabilitate edentulous maxillae with horizontal atrophy and compare them with conventional well-centered implants placed in non-atrophic maxillae after a minimum follow-up of 5 years. A clinical retrospective study was performed of patients that were rehabilitated with full-arch fixed implant-supported maxillary prostheses and had a minimum follow-up of 5 years after implant loading. Patients were divided into 2 groups: patients with class IV maxilla according to Cawood and Howell and treated with palatal positioned implants (test) and with class III maxilla and treated with implants well-centered in the alveolar ridge and completely surrounded by bone (control). The following variables were assessd: age, sex, frequency of toothbrushing, smoking, type of prosthesis, type of implant, implant success, amount of buccal keratinized mucosa, buccal retraction, probing depth, plaque index, modified bleeding index, presence of mucositis or peri-implantitis and peri-implant bone loss. Statistical analysis was performed applying Chi2 Test and Student's t-test using alpha set at 0.05. A total of 57 patients were included: 32 patients with 161 palatal positioned implants (test) and 25 patients with 132 well centered implants (control). No statistically significant differences were found regarding age, sex and smoking, but test group patients reported a significantly higher frequency of daily toothbrushing. Implant success rates were 96.9% for test group implants and 96.0% for control group implants. Peri-implant mucosa retraction was significantly higher in the control group than in the test group (p=0,017). No significant differences were observed either for all the other assessed clinical parameters or for peri-implant bone loss. Despite its limitations the outcomes of the present study suggest that palatal positioned implants may be a good treatment

  1. Dental solid waste characterization and management in Iran: a case study of Sistan and Baluchestan Province.

    PubMed

    Bazrafshan, Edris; Mohammadi, Leili; Mostafapour, Ferdos Kord; Moghaddam, Alireza Ansari

    2014-02-01

    The management of dental solid waste continues to be a major challenge, particularly in most healthcare facilities of the developing world. In Iran, few studies on management of dental solid waste and its composition are available. An effort has been made through this study to evaluate the hazardous and infectious status of dental solid waste, keeping in mind its possible role in cross-infection chain. For this study, 123 private dental centres and 36 public dental centres were selected and the composition and generation rate of dental solid waste produced were measured. Dental solid waste was classified to four main categories: (i) domestic-type; (ii) potentially infectious; (iii) chemical and pharmaceutical; and (iv) toxic, which constituted 11.7, 80.3, 6.3, and 1.7%, respectively, of the total. Also, the results indicated that the dental solid waste per patient per day generation rate for total, domestic-type, potentially infectious, chemical and pharmaceutical, and toxic wastes were 169.9, 8.6, 153.3, 11.2, and 3.3 g/patient/d, respectively. Furthermore, the per day generation rates for total, domestic-type, potentially infectious, chemical and pharmaceutical, and toxic wastes were 194.5, 22.6, 156.1, 12.3, and 3.4 kg/d, respectively. According to findings of this study, for best management of dental waste it is suggested that source reduction, separation, reuse, and recycling programmes be implemented and each section of dental waste be collected and disposed of separately and in accordance with related criteria.

  2. Occurrence and timing of complications following traumatic dental injuries: A retrospective study in a dental trauma department

    PubMed Central

    Lin, Shaul; Pilosof, Nir; Karawani, Munir; Wigler, Ronald; Kaufman, Arieh Y.; Teich, Sorin T.

    2016-01-01

    Background This study explores the pattern of complications occurrence resulting from traumatic dental injuries, the relation of this pattern to the number of years from the time of the injury to its first diagnosis, and other contributing characteristics such as root development and trauma characteristic. Material and Methods Patients’ data treated following dental trauma from 2002 to 2014 were classified and grouped according to age, gender, tooth type, injury type, diagnosis and the time that elapsed between the traumatic event and the diagnosis of complications (TIC). The distribution function of the quantitative parameters was determined with the Kolmogorov-Smirnov test. Fisher exact test was used to test differences between categorical parameters. Results The review identified 166 patients (114 male and 52 female), with a total of 287 traumatized teeth, and a mean of 1.8 injured teeth per incident. Maxillary teeth were involved significantly more often in traumatic dental injuries. The follow-up period range (TIC) had a mean of 2.99 years. The most frequent complication was pulp necrosis (34.2%). The most frequent complication related to avulsion was ankylotic root resorption (50%) diagnosed after a median TIC of 1.18 years. Open apices at the occurrence of trauma were observed in 52 teeth. Of these, 54.9% experienced pulp necrosis and 9.8% inflammatory root resorption with a median TIC of 1.63 years. Teeth that experienced multiple traumatic events showed significantly more late pulp necrosis compared to teeth that experienced a single traumatic injury (61.9% vs. 25.3%, respectively, p<0.0001). Conclusions Follow-up periods should be based on the type of traumatic dental injury and the severity of the potential complications for the tooth. Current recommendations for follow-up after traumatic dental injury should be revised to reflect the need for more frequent and overall prolonged follow-up. Key words:Dental trauma, avulsion, open apex, pulp necrosis

  3. Keeping up with Dental Literature: A Study on Continuing Professional Development among Dental Practitioners in Hubli-Dharwad, India

    PubMed Central

    Rao, Nandita Subba; Ali, Anzil K S; Thadeethra, Mathews Jude

    2017-01-01

    Introduction Continuing Professional Development (CPD) refers to skills and knowledge attained for both personal development and career advancement. In India, very few studies have been documented to discover the patterns of information update by dental practitioners. Aim To discover the educational tools that dentists of Hubli - Dharwad, Karnataka, India, prefer for updating their knowledge on new therapeutic methods and to assess the perceived usefulness of these CPD activities. Materials and Methods Face to face interview was carried out using questionnaire comprising questions on various CPD activities among all the practicing dentists. Pearson’s chi-square test was used to evaluate any association between the frequency of information update and perceived usefulness with gender, qualification, practice types and academic attachments. Results Out of 112 practicing dentists in Hubli-Dharwad, 104 consented for the study. Mean age group of the study population was 32.3±7.56 (SD) years. Discussion with colleagues and discussion with medical sales representatives were the most frequently utilized information sources. On the other hand, attending dental fairs was found to be the most rarely utilized method of information access. Discussion with colleagues, reading textbooks and accessing internet were rated as most useful CPD activities and discussion with sales representatives and attending dental fairs were rated as least useful CPD activities. Conclusion Both conventional methods of information sources like discussions with colleagues and textbook reading as well as contemporary information sources like accessing internet were the preferred methods of information update by dental practitioners of Hubli-Dharwad. PMID:28571256

  4. Class III correction using an inter-arch spring-loaded module

    PubMed Central

    2014-01-01

    Background A retrospective study was conducted to determine the cephalometric changes in a group of Class III patients treated with the inter-arch spring-loaded module (CS2000®, Dynaflex, St. Ann, MO, USA). Methods Thirty Caucasian patients (15 males, 15 females) with an average pre-treatment age of 9.6 years were treated consecutively with this appliance and compared with a control group of subjects from the Bolton-Brush Study who were matched in age, gender, and craniofacial morphology to the treatment group. Lateral cephalograms were taken before treatment and after removal of the CS2000® appliance. The treatment effects of the CS2000® appliance were calculated by subtracting the changes due to growth (control group) from the treatment changes. Results All patients were improved to a Class I dental arch relationship with a positive overjet. Significant sagittal, vertical, and angular changes were found between the pre- and post-treatment radiographs. With an average treatment time of 1.3 years, the maxillary base moved forward by 0.8 mm, while the mandibular base moved backward by 2.8 mm together with improvements in the ANB and Wits measurements. The maxillary incisor moved forward by 1.3 mm and the mandibular incisor moved forward by 1.0 mm. The maxillary molar moved forward by 1.0 mm while the mandibular molar moved backward by 0.6 mm. The average overjet correction was 3.9 mm and 92% of the correction was due to skeletal contribution and 8% was due to dental contribution. The average molar correction was 5.2 mm and 69% of the correction was due to skeletal contribution and 31% was due to dental contribution. Conclusions Mild to moderate Class III malocclusion can be corrected using the inter-arch spring-loaded appliance with minimal patient compliance. The overjet correction was contributed by forward movement of the maxilla, backward and downward movement of the mandible, and proclination of the maxillary incisors. The molar relationship was

  5. Class III correction using an inter-arch spring-loaded module.

    PubMed

    Vanlaecken, Robert; Williams, Michael O; Razmus, Thomas; Gunel, Erdogan; Martin, Chris; Ngan, Peter

    2014-05-02

    A retrospective study was conducted to determine the cephalometric changes in a group of Class III patients treated with the inter-arch spring-loaded module (CS2000®, Dynaflex, St. Ann, MO, USA). Thirty Caucasian patients (15 males, 15 females) with an average pre-treatment age of 9.6 years were treated consecutively with this appliance and compared with a control group of subjects from the Bolton-Brush Study who were matched in age, gender, and craniofacial morphology to the treatment group. Lateral cephalograms were taken before treatment and after removal of the CS2000® appliance. The treatment effects of the CS2000® appliance were calculated by subtracting the changes due to growth (control group) from the treatment changes. All patients were improved to a Class I dental arch relationship with a positive overjet. Significant sagittal, vertical, and angular changes were found between the pre- and post-treatment radiographs. With an average treatment time of 1.3 years, the maxillary base moved forward by 0.8 mm, while the mandibular base moved backward by 2.8 mm together with improvements in the ANB and Wits measurements. The maxillary incisor moved forward by 1.3 mm and the mandibular incisor moved forward by 1.0 mm. The maxillary molar moved forward by 1.0 mm while the mandibular molar moved backward by 0.6 mm. The average overjet correction was 3.9 mm and 92% of the correction was due to skeletal contribution and 8% was due to dental contribution. The average molar correction was 5.2 mm and 69% of the correction was due to skeletal contribution and 31% was due to dental contribution. Mild to moderate Class III malocclusion can be corrected using the inter-arch spring-loaded appliance with minimal patient compliance. The overjet correction was contributed by forward movement of the maxilla, backward and downward movement of the mandible, and proclination of the maxillary incisors. The molar relationship was corrected by mesialization of the

  6. Modeling Outcomes: Modified Aortic Arch Advancement for Neonatal Hypoplastic Arch.

    PubMed

    Nellis, Joseph R; Chung, Timothy K; Agarwal, Nandita; Torres, Jose E; Holgren, Sarah E; Raghavan, Madhavan L; Turek, Joseph W

    Numerous surgical approaches regarding aortic arch advancement for neonatal arch hypoplasia have been described. These repairs can be classified into two categories: those that incorporate a patch and those that do not. The decision between repairs remains largely experiential, rather than empirical, because of the limited number of reported outcomes. We report early outcomes from neonates undergoing modified aortic arch advancement with an anterior patch and our experience using computational fluid dynamic modeling to better understand the hemodynamic consequences associated with this repair. A retrospective review of neonates undergoing aortic arch advancement with anterior patch in 2014 at a single institution was performed. Anatomical, perioperative, and follow-up data were collected. Three-dimensional cardiac magnetic resonance images were used to generate computational fluid dynamic models of the modified anterior patch and direct end-to-side repairs. Cardiac waveform inputs were simulated and hemodynamic analyzed. Ten neonates underwent modified aortic arch advancement. No hemodynamically significant gradients were observed at a median follow-up of 0.77 (0.30-1.2) years. Asymmetrical flow was observed in the end-to-side repair, whereas more concentric laminar flow was observed throughout the modified model. Spatial variations in velocities immediately distal to the anastomosis were greater in the end-to-side model (0.35 vs 0.17 m/s, P < 0.001). Time-averaged variations in wall shear stress during systole were greater in the end-to-side model at the same location (3.44 vs 1.98 dynes/cm, P < 0.001). Early outcomes after the use of an anterior patch for neonatal hypoplastic aortic arch repair show favorable hemodynamic outcomes.

  7. Tooth replacements in young adults with severe hypodontia: Orthodontic space closure, dental implants, and tooth-supported fixed dental prostheses. A follow-up study.

    PubMed

    Hvaring, Christina L; Øgaard, Bjørn; Birkeland, Kari

    2016-10-01

    Children with severe hypodontia have a substantial impairment of their dental health starting early in life. The purpose of this study was to describe types and locations of substitutes for missing teeth in patients with severe hypodontia and to compare the crown and soft tissue morphologies of orthodontic space closure, dental implants, and tooth-supported fixed dental prostheses for replacing teeth in the anterior region. Fifty patients missing 6 or more teeth and aged 18 years or older (mean age, 25.6 years) took part in a follow-up study. The patients were examined clinically with panoramic radiographs and clinical photographs. Crown and soft tissue variables (mucosal discoloration, crown morphology, color, and papilla index) were compared for orthodontic space closure, dental implant fixtures, and fixed dental prostheses. Dental implants, orthodontic space closure, and retaining deciduous teeth were the most commonly prescribed treatments. Persisting deciduous teeth showed a good survival rate at the follow-up examination. Mucosal discoloration was seen only for implant fixtures and was evident for almost all fixtures in the anterior mandible and two thirds of those in the anterior maxilla. The papilla index scored poorer for both implant fixtures and fixed dental prostheses compared with orthodontic space closure. Dental implants in the anterior region proved to be an inadequate treatment modality in patients with severe hypodontia because of pronounced mucosal discoloration. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  8. A Pioneering Study of Dental Fluorosis in the Libyan Population

    PubMed Central

    L, Sunil Tejaswi K; Shetty, Suneeth; M, Annapoorna B; Pujari, Sudarshan C; P, Sarveshwar Reddy; Nandlal, B

    2013-01-01

    Background: Fluorosis is a condition resulting from excessive ingestion of fluoride during early childhood leading to the formation of defective enamel. The increased fluoride content is thought to result in a metabolic alteration of ameloblasts, which results in defective matrix, and improper calcification of teeth. Materials and Methods: A total of 6244 patients between the ages of 6yrs to 60yrs, who presented to our outpatient clinic from October 2009 to December 2010 were included in the study. The study subjects were grouped according to their age into the following groups- 6-14 yrs, 15-25 yrs, 26-40 yrs, and 40-60yrs. Only permanent dentition was taken into consideration in this study. Results: The overall prevalence of fluorosis in this study was 63.34% (3955 of 6244 patients). Men had a slightly higher prevalence of 64.27% compared to 62.28% among women. Conclusion: Prevention of fluorosis would require efforts at raising awareness among the people about the harmful effects of their dietary choices on their teeth. They also need to be educated about adequate and proper oral hygiene, such as brushing their teeth at least two times daily. How to cite this article: Sunil T K L, Shetty S, Annapoorna B M, Pujari S C, Reddy P S, Nandlal B. A Pioneering Study of Dental Fluorosis in the Libyan Population. J Int Oral Health 2013; 5(3):67-72. PMID:24155605

  9. Cluster Effects in a National Dental PBRN Restorative Study

    PubMed Central

    Litaker, M.S.; Gordan, V.V.; Rindal, D.B.; Fellows, J.L.; Gilbert, G.H.

    2013-01-01

    Items in clusters, such as patients of the same clinician or teeth within the same patient, tend to be more similar than items from different groups. This within-group similarity, represented by the intraclass correlation coefficient (ICC), reduces precision, yielding less statistical power and wider confidence intervals, compared with non-clustered samples of the same size. This must be considered in the design of studies including clusters. We present ICC estimates from a study of 7,826 restorations placed in previously unrestored tooth surfaces of 4,672 patients by 222 clinicians in the National Dental Practice-Based Research Network, as a resource for sample size planning in restorative studies. Our findings suggest that magnitudes of ICCs in practice-based research can be substantial. These can have large effects on precision and the power to detect treatment effects. Generally, we found relatively large ICCs for characteristics that are influenced by clinician choice (e.g., 0.36 for rubber dam use). ICCs for outcomes within individual patients, such as tooth surfaces affected by a caries lesion, tended to be smaller (from 0.03 to 0.15), but were still sufficiently large to substantially affect statistical power. Clustering should be taken into account in the design of oral health studies and derivation of statistical power estimates for these studies (ClinicalTrials.gov, NCT00847470). PMID:23857643

  10. Fixed Full Arches Supported by Tapered Implants with Knife-Edge Thread Design and Nanostructured, Calcium-Incorporated Surface: A Short-Term Prospective Clinical Study

    PubMed Central

    Bechara, Soheil; Lukosiunas, Algirdas; Kubilius, Ricardas

    2017-01-01

    Purpose. To evaluate implant survival, peri-implant bone loss, and complications affecting fixed full-arch (FFA) restorations supported by implants with a knife-edge thread design and nanostructured, calcium-incorporated surface. Methods. Between January 2013 and December 2015, all patients referred for implant-supported FFA restorations were considered for enrollment in this study. All patients received implants with a knife-edge thread design and nanostructured calcium-incorporated surface (Anyridge®, Megagen, South Korea) were restored with FFA restorations and enrolled in a recall program. The final outcomes were implant survival, peri-implant bone loss, biologic/prosthetic complications, and “complication-free” survival of restorations. Results. Twenty-four patients were selected. Overall, 215 implants were inserted (130 maxilla, 85 mandible), 144 in extraction sockets and 71 in healed ridges. Thirty-six FFAs were delivered (21 maxilla, 15 mandible): 27 were immediately loaded and 9 were conventionally loaded. The follow-up ranged from 1 to 3 years. Two fixtures failed, yielding an implant survival rate of 95.9% (patient-based). A few complications were registered, for a “complication-free” survival of restorations of 88.9%. Conclusions. FFA restorations supported by implants with a knife-edge thread design and nanostructured, calcium-incorporated surface are successful in the short term, with high survival and low complication rates; long-term studies are needed to confirm these outcomes. PMID:28246595

  11. Fixed Full Arches Supported by Tapered Implants with Knife-Edge Thread Design and Nanostructured, Calcium-Incorporated Surface: A Short-Term Prospective Clinical Study.

    PubMed

    Bechara, Soheil; Lukosiunas, Algirdas; Dolcini, Giorgio Andrea; Kubilius, Ricardas

    2017-01-01

    Purpose. To evaluate implant survival, peri-implant bone loss, and complications affecting fixed full-arch (FFA) restorations supported by implants with a knife-edge thread design and nanostructured, calcium-incorporated surface. Methods. Between January 2013 and December 2015, all patients referred for implant-supported FFA restorations were considered for enrollment in this study. All patients received implants with a knife-edge thread design and nanostructured calcium-incorporated surface (Anyridge®, Megagen, South Korea) were restored with FFA restorations and enrolled in a recall program. The final outcomes were implant survival, peri-implant bone loss, biologic/prosthetic complications, and "complication-free" survival of restorations. Results. Twenty-four patients were selected. Overall, 215 implants were inserted (130 maxilla, 85 mandible), 144 in extraction sockets and 71 in healed ridges. Thirty-six FFAs were delivered (21 maxilla, 15 mandible): 27 were immediately loaded and 9 were conventionally loaded. The follow-up ranged from 1 to 3 years. Two fixtures failed, yielding an implant survival rate of 95.9% (patient-based). A few complications were registered, for a "complication-free" survival of restorations of 88.9%. Conclusions. FFA restorations supported by implants with a knife-edge thread design and nanostructured, calcium-incorporated surface are successful in the short term, with high survival and low complication rates; long-term studies are needed to confirm these outcomes.

  12. Models of practice organisation using dental therapists: English case studies.

    PubMed

    Sun, N; Harris, R V

    2011-08-12

    A new dental remuneration system based on bands of activity has changed the reward system operating in dental practices and influenced practitioner behaviour in relation to the delegation of tasks to English dental therapists (DTs). Since dental practitioners operate as independent contractors they are free to innovate. A variety of models incorporating DTs in general practice teams exist, some of which may overcome the apparent delegation constraints embedded within this system of remuneration. To describe the way different practices are organised to take account of DTs in their teams and identify whether any of these models address delegation disincentives arising from the system of remuneration. A purposive sample of six dental practices was identified, comprising two small, two medium and two large dental practices, including a variety of models of practice organisation. Semi-structured interviews were carried out with principal dentists, associate dentists, DTs, practice managers and dental hygienists (35 participants in total). A thematic analysis was applied to interview transcripts. The six dental practices demonstrated six different models of practice organisation which could be grouped into 'practice payment' and 'dentist payment' models according to whether the salary costs of the DT were met by a central practice fund or from the income of individual dentists in the team. In both of the large practices only some of the dentists in the team referred work to the DT because of reimbursement issues. In two practices the system was perceived to be satisfactory to all parties, one of these being a single-handed practice with two DTs. Although the remuneration system contained some potential disincentives to DT delegation, some practices innovated in their organisations to overcome these issues.

  13. Catalog of Completed Health Care and Dental Care Studies.

    DTIC Science & Technology

    1987-12-01

    Goldberg, G. (in press). Dental insurance and the oral health of preschool children. Journal of the American Dental Association. Chisick, M., Davies...military medical officers toward the use of drug substances, The International Journal of Addictions, 18 (1), 37-44. 28 Georqoulakis, James M. (1983). Self ...Annual Meeting of the Military Testing Association. Munich, Federal Republic of West Germany. 34 Georgoulakis, James M. (1984). Measurement of self

  14. Dental anxiety in relation to neuroticism and pain sensitivity. A twin study.

    PubMed

    Vassend, Olav; Røysamb, Espen; Nielsen, Christopher S

    2011-03-01

    Predisposing personality traits as well as heightened pain sensitivity and fear of pain have been hypothesized as central factors in the development of dental anxiety. The aim of the study was to estimate the heritability of dental anxiety, and to investigate the genetic and environmental sources of covariance between dental anxiety on one hand, and pain sensitivity and the neuroticism trait on the other. A sample comprising 188 twins, aged 23-35 years (53 monozygotic and 39 dizygotic twin pairs, and 4 single twins whose co-twin did not participate), was included in the study. Measures of dental anxiety and perso