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Sample records for removable partial denture

  1. Inconspicuous retention for removable partial dentures.

    PubMed

    King, G E; Barco, M T; Olson, R J

    1978-05-01

    Many dentists and patients believe that removable partial dentures have an unesthetic appearance when they replace anterior teeth because of the visible clasps. Two methods of obtaining inconspicuous retention have been described. PMID:349140

  2. Precision metal occlusal surfaces for removable partial dentures.

    PubMed

    Barco, M T; Synnott, S A

    1989-01-01

    The prosthodontist is often limited in developing the desired occlusal pattern when integrating removable partial dentures with natural dentitions or fixed partial dentures. A technique that allows the development of an esthetic, accurate metal occlusal surface for a removable partial denture is described. The occlusion developed allows an occlusal harmony with the removable partial denture that is not possible with stock denture teeth or metal occlusal surfaces developed with stock denture teeth. PMID:2700630

  3. Implants in conjunction with removable partial dentures: a literature review.

    PubMed

    Mijiritsky, Eitan

    2007-06-01

    Although the benefits of implant-borne removable prostheses are readily apparent for the fully edentulous patient and have been well documented, there is a paucity of studies concerning the combination of implants with removable partial dentures in partially edentulous patients. The aim of this article is to review the literature regarding implants with removable partial dentures and evaluate the evidence for this clinical approach. A MEDLINE/PubMed search from 1990 to 2006, focusing on the use of implants with removable partial dentures and related features, was supplemented with a hand search to identify relevant peer-reviewed English articles published in dental journals and textbooks on removable partial dentures. PMID:17563505

  4. Masticatory and nutritional aspects on fixed and removable partial dentures.

    PubMed

    Liedberg, B; Norlén, P; Owall, B; Stoltze, K

    2004-03-01

    The aim of the present study was to evaluate mastication, food selection and nutritional aspects in two groups of persons restored with fixed (FPD, N=44) and removable (RPD, N=40) partial dentures respectively. The subjects were part of a cohort study of 67-68-year-old men living in Malmö, Sweden. The two groups were very similar regarding social factors and the inclusion criteria were chosen so that the groups were very equal regarding oral factors, apart from the difference in fixed and removable partial dentures. The number of natural teeth, number of replaced teeth and occlusal contacts did not differ significantly between the two groups, nor did the distribution of maxillary and mandibular dentures. A comprehensive examination of several general health factors included a home interview of dietary habits. A clinical examination included a 20-minute oral examination with registration of number of teeth, FPDs, RPDs, and occlusal contacts. It also included masticatory tests: chewing gum colour mixing, chewing gum bolus shaping, and swallowing threshold (number of strokes to the first swallow of an almond). The consumption of hard and soft foods was revealed by the dietary interview as well as the intake of energy and some nutrients. There was a significant difference between the groups regarding the capacity to mix the two-coloured chewing gum, to shape the chewing gum bolus and in the consumption of hard foods. There was no difference in the swallowing threshold and the consumption of soft foods. The intake of energy and nutrients did not differ significantly between the groups. The differences in masticatory capacity found thus seem to have little, if any, effect on the factors of importance for general health. A reasonable explanation for the differences found is that artificial teeth that are well retained, such as FPDs, make more active chewing possible than do removable, and often somewhat loose-fitting partial dentures. PMID:15029484

  5. The significance of major connectors and denture base mucosal contacts on the functional strain patterns of maxillary removable partial dentures.

    PubMed

    Fernandes, C P; Glantz, P O

    1998-06-01

    The purpose of this study was to investigate the biomechanical significance of major connectors and base mucosal contacts on the mechanical behaviour of maxillary removable partial dentures in vivo. Six subjects wearing maxillary dentures retained by conical crowns were selected for the study. Reflective photoelasticity and strain gauges were used to monitor the development of strain/stress during functional loading. Loading tests were performed initially with a denture design including a palatal major connector and denture bases and then repeated after removal of the major connectors and denture base alveolar muccosa contacts. The palatal major connector and the denture bases mucosal contacts contribute significantly to the rigidity and stability of removable partial dentures retained by conical crowns. PMID:9927921

  6. Epidemiological Data and Survival Rate of Removable Partial Dentures

    PubMed Central

    Moreno, Amália; Haddad, Marcela Filié; Rocha, Eduardo Passos; Assunção, Wirley Gonçalves; Filho, Humberto Gennari; Santos, Emerson Gomes Dos; Sonego, Mariana Vilela; Santos, Daniela Micheline Dos

    2016-01-01

    Introduction The use of removable partial denture (RPD) is considered as low-cost and common treatment option to rehabilitate edentulous areas. Aim This study aimed to investigate the epidemiological data of patients rehabilitated with removable partial denture (RPD) in order to assess treatment survival rate and failures. Materials and Methods Epidemiological data and medical records of patients treated with RPD between 2007 and 2012 at the RPD discipline of a Brazilian University (Aracatuba Dental School- UNESP) were evaluated as well as dental records of patients who underwent RPD treatments (fabrication or repairs) between 2000 and 2010. Factors such as gender, age, presence of systemic disease, main complaint, edentulous arch, period and cause of denture replacement and the prosthesis characteristics were recorded. The chi-square test was used to assess the differences between the variables and the Kaplan Meyer to assess the survival of the RPDs evaluated. Results A total of 324 maxillary RPD and 432 mandibular RPD were fabricated. Most of the patients were women aging 41 to 60-year-old. The number of mandibular RPD Kennedy class I (26%) was statistically higher for the maxillary arch (p<.05). There was no association between main complaint to gender or the presence of systemic disease. The lingual plate was the most common major connector used in the mandible (32%). The main reason for altering the design of replaced RPDs were changes during treatment plan. Conclusion The number of patients who require RPD is large; most of RPDs are Kennedy Class I. A good treatment plan is very important for achieving a positive treatment outcome, and it is strictly related to the survival rate. PMID:27437367

  7. [Effects of removable partial dentures on the quality of life in people with shortened dental arches].

    PubMed

    Armellini, D B; Heydecke, G; Witter, D J; Creugers, N H J

    2009-12-01

    In order to assess the enhanced value of removable partial dentures on the quality of life, patients at 2 university clinics were screened for the presence of complete or shortened dental arches. Those selected were assigned to 1 of 5 subgroups: 1) a shortened dental arch with all frontal teeth, 2) a shortened dental arch with one or more frontal diastemas, 3) a shortened dental arch with all frontal teeth, restored by a removable partial denture, 4) a shortened dental arch and several diastemas, restored by a removable partial denture, 5) a complete dental arch. The participants completed the Oral Health Impact Profile (OHIP-49) and the Short Form Health Survey (SF-36). Clinical data recorded were: whether any teeth were missing and if so which, whether or not these had been replaced by a removable partial denture, and the number of occluding pairs of (pre)molars. The results revealed that a shortenend dental arch has a certain impact on the quality of life. However, the participants only experienced benefits from a removable partial denture if the denture also replaced frontal teeth. PMID:20101937

  8. Clinical evaluation of abutment teeth of removable partial denture by means of the Periotest method.

    PubMed

    Jorge, J H; Giampaolo, E T; Vergani, C E; Machado, A L; Pavarina, A C; Cardoso de Oliveira, M R

    2007-03-01

    Prosthodontics should be one of the means of establishing conditions for the maintenance of periodontal health. The forces applied to the abutment teeth and their effects are very important considerations in the design and construction of the removable partial dentures. This 6-month follow-up clinical study evaluated the degree of mobility of abutment teeth of distal extension and tooth supported removable partial dentures by using Periotest. Two types of clasp design were selected for evaluation. In cases with unilateral and bilateral distal-extension, a clasp design including a T clasp of Roach retentive arm, a rigid reciprocal arm and a mesial rest were used. For the abutments of tooth-supported removable partial dentures, a second clasp design with a cast circumferential buccal retentive arm, a rigid reciprocal clasp arm and a rest adjacent to the edentulous ridges was selected. A total of 68 abutment teeth was analysed. Periotest values were made at the time of denture placement (control) and at 1, 3 and 6 months after the denture placement. The statistical analysis was performed using Friedman test. All analysis was performed at a 0.05 level of significance. The results revelled that no significant changes in tooth mobility were observed during the 6-months follow-up (P > 0.05). In conclusion, our findings suggest that adequate oral hygiene instructions, careful prosthetic treatment planning and regular recall appointments play an important role in preventing changes in abutment tooth mobility caused by removable partial denture placement. PMID:17302951

  9. Removable Partial Denture Supported by Implants with Prefabricated Telescopic Abutments - A Case Report

    PubMed Central

    Sehgal, Komal

    2014-01-01

    Implants have been designed to rehabilitate edentulous patients with fixed prosthesis or implant supported overdentures. Implant-supported single crowns and fixed partial dentures have become successful treatment alternatives to removable and fixed partial dentures. However, it is common to have clinical situations which make it impossible to use conventional as well as implant supported fixed partial dentures. The implant supported removable partial dentures can be a treatment modality that offers the multitude of benefits of implant-based therapy—biologic, biomechanical, social, and psychological to such patients. The aim of this article is to present a case report describing the fabrication and advantages of removable partial denture supported by teeth and implants for a patient with long edentulous span. The patient was satisfied with his dentures in terms of function and aesthetics. Regular follow-up visits over a period of three years revealed that the periodontal condition of remaining natural dentition and peri-implant conditions were stable. There was no evidence of excessive residual ridge resorption or mobility of the teeth, nor were any visible changes in the bone levels of the natural teeth or implants noted on radiographs. PMID:25121066

  10. Clinical Evaluation of Removable Partial Dentures on the Periodontal Health of Abutment Teeth: A Retrospective Study

    PubMed Central

    Dula, Linda J; Ahmedi, Enis F; Lila-Krasniqi, Zana D; Shala, Kujtim Sh

    2015-01-01

    The aim of this retrospective study was to evaluate the effect of removable partial dentures in periodontal abutment teeth in relation to the type of denture support and design of RPD in a five-year worn period. Methods : A total of 64 patients with removable partial dentures (RPDs), participated in this study. It were examined ninety-one RPDs. There were seventy-five RPDs with clasp-retained and sixteenth were RPDs with attachments. There were 28 females and 36 males, aged between 40-64 years, 41 maxillary and 50 mandible RPDs. For each subjects the following data were collected: denture design, denture support, and Kennedy classification. Abutment teeth were assessed for plaque index (PI), calculus index (CI), blending on probing (BOP), probing depth (PD), gingival recession (GR), tooth mobility (TM). Level of significance was set at p<0.05. Results : According to denture support of RPD, BOP, PD, PI, GR, CI and TM-index showed no statistically significant difference. Based on the denture design of RPD’s, BOP, PD, PI, CI, and TM-index proved no statistically significant difference. Except GR-index according to denture design confirmed statistically significant difference in RPD with clasp p<0.01. The higher values of all periodontal parameter as BOP, PD, PI, CI and TM were in patients with RPD’s with claps comparing with RPD’s with attachment. Conclusion : RPD’s with clasp increased level of gingival inflammation in regions covered by the dentures and below the clasp arms in abutment teeth. PMID:25926896

  11. Clinical evaluation of removable partial dentures on the periodontal health of abutment teeth: a retrospective study.

    PubMed

    Dula, Linda J; Ahmedi, Enis F; Lila-Krasniqi, Zana D; Shala, Kujtim Sh

    2015-01-01

    The aim of this retrospective study was to evaluate the effect of removable partial dentures in periodontal abutment teeth in relation to the type of denture support and design of RPD in a five-year worn period. Methods : A total of 64 patients with removable partial dentures (RPDs), participated in this study. It were examined ninety-one RPDs. There were seventy-five RPDs with clasp-retained and sixteenth were RPDs with attachments. There were 28 females and 36 males, aged between 40-64 years, 41 maxillary and 50 mandible RPDs. For each subjects the following data were collected: denture design, denture support, and Kennedy classification. Abutment teeth were assessed for plaque index (PI), calculus index (CI), blending on probing (BOP), probing depth (PD), gingival recession (GR), tooth mobility (TM). Level of significance was set at p<0.05. Results : According to denture support of RPD, BOP, PD, PI, GR, CI and TM-index showed no statistically significant difference. Based on the denture design of RPD's, BOP, PD, PI, CI, and TM-index proved no statistically significant difference. Except GR-index according to denture design confirmed statistically significant difference in RPD with clasp p<0.01. The higher values of all periodontal parameter as BOP, PD, PI, CI and TM were in patients with RPD's with claps comparing with RPD's with attachment. Conclusion : RPD's with clasp increased level of gingival inflammation in regions covered by the dentures and below the clasp arms in abutment teeth. PMID:25926896

  12. Reappraisal of the removable partial denture as a treatment option for the shortened dental arch.

    PubMed

    Nassani, Mohammad Zakaria; Tarakji, Bassel; Baroudi, Kusai; Sakka, Salah

    2013-04-01

    For patients with shortened dental arches, many treatment options are available. The existing situation can be maintained by stabilizing the present dentition and improving the occlusion without extending the arch. Alternatively, the shortened dental arch can be extended by either a free-end saddle removable partial denture, cantilevered fixed bridge, or by an implant-supported prosthesis. The free-end saddle removable partial denture can be considered a simple, non-invasive, and relatively cheap treatment option for the shortened dental arch. It was believed that such prosthodontic rehabilitation would be beneficial for the patients in terms of improving oral functions. However, the existing literature indicates that the prognosis of free-end saddle removable partial denture is not predictable, it is problematic, and its contribution to oral functions in patients with shortened dental arches is considered to be dubious. This paper reviews and summarizes the current literature about the outcome of extending the shortened dental arch by a free-end saddle removable partial denture. It also outlines factors that may affect the prognosis of this prosthetic treatment. PMID:24883037

  13. Factors influencing the provision of removable partial dentures by dentists in Ireland.

    PubMed

    Allen, Finbarr

    2010-01-01

    Factors influencing clinical treatment of partially dentate patients are varied, and there is a need to identify factors influencing success in the provision of removable partial dentures. The aim of this study was to assess the attitudes of general dental practitioners (GDPs) in Ireland towards tooth replacement and use of RPDs, in partially dentate older adults. The sample frame was the Register of Dentists in Ireland; data were also collected from a sample of dentists practising under NHS regulations in Northern Ireland. Validated questionnaires were sent to all dentists on the Register of Dentists in the Republic of Ireland, and dentists working under NHS regulations registered with the Central Services Agency in Northern Ireland. Content of the questionnaire included details of the dentist themselves, their dental practice and the profile of partial denture provision. They were also asked to give their views on factors influencing the success or failure of an RPD, the process of providing RPDs and their attitudes to RPD provision. A total of 1,143 responses were received, a response rate of 45%. A mean number of 61 RPDs per annum were provided, with 75% of dentures provided being acrylic based. Respondents indicate their belief that cobalt-chromium based dentures had a longer prognosis than acrylic dentures, but less than half (46%) claim to design the frameworks themselves. Patients' attitudes are considered influential in the success of RPD provision, and their influence on appearance is considered the most important factor influencing success. The most important factors influencing failure are: the patient not requesting a denture; an RPD restoring unbounded saddles; and, lower RPDs. Although considered important, approximately 60% of the sample do not routinely organise follow-up appointments for patients provided with RPDs. The fee structures in the DTSS and DTBS are considered a barrier to quality in the provision of partial dentures. PMID:21192619

  14. Fabrication of a new crown and provisional to an existing removable partial denture.

    PubMed

    Jackson, A D; Butler, C J

    1995-09-01

    A method of fabricating a new crown to an existing removable partial denture is described. A press-form plastic shell made from the diagnostic cast provides the outer contours for the abutment tooth, while an acrylic resin coping is fabricated on a die to provide accurate internal adaptation. The acrylic resin coping is seated on the prepared abutment. Autopolymerizing acrylic resin is mixed and placed in the plastic shell that is then placed in the mouth over the coping, forming the acrylic resin crown pattern. The removable partial prosthesis is fitted over the crown pattern intraorally. The pattern is transferred back to the die, the margins are refined, and the casting is completed and finished, avoiding reduction of the established contours. The same plastic shell is used with tooth-shaded acrylic resin to construct a provisional crown directly in the mouth. This technique allows the patient to wear the removable partial denture while the laboratory procedures are completed. PMID:8603212

  15. Immediate replacement removable partial dentures with cobalt-chromium frameworks: rationale, technology and a case report.

    PubMed

    Hassan, L; Juszczyk, A S; Clark, R K F

    2005-10-01

    The advantages of removable partial dentures with cobalt-chromium frameworks over those made entirely of acrylic resin, in oral health and hygiene, are well documented. However, in cases where teeth are to be extracted for fitting the removable partial denture, a difficulty arises because of the need to test the fit of the removable partial denture framework. The advent of two modern technologies-- laser welding and metal bonding agents -- make it possible to test the fit of the major part of the framework prior to adding additional metal components to support artificial teeth. A case is described in which the four lower incisors were extracted. The main part of the framework was constructed and its fit tested. A second casting was laser-welded to the lingual plate of the first casting to support the artificial incisor teeth. This technique avoids the need to make an acrylic resin temporary denture but incurs the cost of the additional technical work and so the advantages may be considered to be economically neutral. PMID:16159357

  16. Relevance of Variations in the Opposing Dentition for the Functionality of Fixed and Removable Partial Dentures: A Systematic Review

    PubMed Central

    Pommer, Bernhard; Krainhöfner, Martin; Watzek, Georg; Tepper, Gabor; Dintsios, Charalabos-Markos

    2012-01-01

    The aim of this systematic review was to evaluate the functionality of fixed and removable partial dentures as test interventions in relation to variations in the opposing dentition and their prosthetic restoration. The abstracts identified in the respective databases were screened independently by two investigators. RCTs and uncontrolled studies were considered, provided the patients were included consecutively and the confounding variables were adequately monitored. Seventeen papers were included. The study and publication quality was assessed using a “biometric quality” tool showing an overall poor quality. The reported outcomes, such as survival rates, were in each case obtained from a single study. Two possible trends could be deduced for the endpoint longevity: (a) the first trend in favor of removable partial dentures, compared to fixed partial dentures, with a fully edentulous opposing arch fitted with a removable prosthesis; (b) the second trend in favor of implant-supported partial dentures, compared to conventionally fixed partial dentures, with natural opposing dentition or with a removable partial denture in the opposing arch. No evidence could be generated as to whether, and if so how, variations in the opposing dentition have a bearing on the decision to fit a partially edentulous arch with a fixed or removable partial denture. PMID:23193407

  17. All-cast-titanium removable partial denture for a patient with a severely reduced interarch distance: a case report.

    PubMed

    Wakabayashi, N; Mizutani, H; Ai, M

    1997-03-01

    A patient had a maxillary posterior edentulous area and severely reduced interarch distance that precluded the use of a conventional removable partial denture. An all-cast-titanium denture base and occlusal surface was designed to fabricate a removable denture to restore the edentulous area. Titanium was cast in a centrifugal casting machine with electric are melting design. The desirable characteristics of titanium, such as favorable mechanical properties, low density, and comparatively low cost, make this metal particularly effective and suitable for construction of an all-cast-metal denture base with a metal occlusal surface. PMID:9452683

  18. Resilient Attachments as an Alternative to Conventional Cast Clasp Removable Partial Denture: 3-Year Follow-up.

    PubMed

    Schuh, Cristian; Adiel Skupien, Jovito; Mesko, Mauro Elias; Valentini, Fernanda; Pereira-Cenci, Tatiana; Boscato, Noéli

    2014-12-01

    The present clinical report describes the prosthodontic management for a patient with uncontrolled bleeding and diabetes mellitus treated with a maxillary complete denture and a mandibular partial fixed dental prosthesis designed to interface with a removable cast framework partial denture retained by 2 ERA attachments. This approach was undertaken to improve both retention and stability of the distal extension Kennedy Class I removable partial denture. The rehabilitation provided better anterior esthetics than if treated with a conventional clasp retained removable partial denture, by employing a simple, practical design and offering a significant biomechanical advantages, restoring both oral health and function. Thus, this treatment modality, involving an ERA system and transfixation in fixed crowns, is an effective treatment and can be indicated as a clinical alternative for edentulous and partially edentulous patients with systemic disorders or for patients in economic situations that might preclude implant-based rehabilitation. PMID:26199530

  19. Computerized design of removable partial dentures: a knowledge-based system for the future.

    PubMed

    Davenport, J C; Hammond, P; Fitzpatrick, F J

    1993-06-01

    Dentists frequently fail to provide dental technicians with the design information necessary for the construction of removable partial dentures. The computerization of dental practices and the development of appropriate knowledge-based systems could provide a powerful tool for improving this aspect of dental care. This article describes one such system currently under development which is an example of the kind of additional facility that will become available for those practices with the necessary hardware. PMID:8299844

  20. Implant-assisted removable partial dentures as an alternative treatment for partial edentulism: a review of the literature.

    PubMed

    Chatzivasileiou, Konstantinos; Kotsiomiti, Eleni; Emmanouil, Ioannis

    2015-01-01

    This study reviewed the current literature concerning implant-assisted removable partial dentures (RPDs) in order to present the existing knowledge about performance issues. An electronic search was conducted on the PubMed database for published English-language articles that contained information about implant-assisted RPDs. A review of these articles indicated that the combination of dental implants with RPDs constitutes a cost-efficient prosthetic protocol that can offer solutions to problematic aspects of treatment with removable partial dentures. Well-designed studies are still needed to provide robust evidence on critical issues, such as design guidelines, long-term survival of implants associated with RPDs, and their effect on patients' quality of life. PMID:25734282

  1. Impact on Dietary Intake of Removable Partial Dentures Replacing a Small Number of Teeth.

    PubMed

    Inomata, Chisato; Ikebe, Kazunori; Okada, Tadashi; Takeshita, Hajime; Maeda, Yoshinobu

    2015-01-01

    The aim of this study was to clarify the impact of wearing removable partial dentures (RPDs) replacing a small number of teeth on dietary intake. Participants had at least 20 teeth and were classified as Eichner B1 or B2. The participants underwent dental and oral examinations, and their dietary intake was assessed. Analysis of covariance showed that RPD wearers consumed more vegetables, n-3 fatty acids, calcium, vitamin A, and dietary fiber than nonwearers after adjusting for possible confounding factors. It is concluded that RPDs are effective for improving dietary intake even in participants who have lost a small number of teeth. PMID:26523716

  2. Retrofitting a Crown Supporting a Removable Partial Denture Using "Biogeneric Copy" to Replicate Tooth's Preoperative Condition.

    PubMed

    Patel, Dhaval

    2016-02-01

    When a crown that supports a removable partial denture (RPD) needs to be replaced, patients often balk at having to wait several weeks for laboratory production to be completed before receiving the new restoration. Moreover, the fit of the lab-produced unit may not always be satisfactory. CEREC® CAD/CAM technology provides a design method known as Biogenetic Copy, which allows a clinician to replicate the preexisting size, shape, and form of a tooth chairside. As this case report demonstrates, using this method to retrofit a crown under an existing RPD prosthesis can result in a predictable, accurate, durable, and esthetic same-day restorative solution. PMID:26905091

  3. Strain Distribution in a Kennedy Class I Implant Assisted Removable Partial Denture under Various Loading Conditions

    PubMed Central

    Shahmiri, Reza; Aarts, John M.; Bennani, Vincent; Swain, Michael V.

    2013-01-01

    Purpose. This in vitro study investigates how unilateral and bilateral occlusal loads are transferred to an implant assisted removable partial denture (IARPD). Materials and Methods. A duplicate model of a Kennedy class I edentulous mandibular arch was made and then a conventional removable partial denture (RPD) fabricated. Two Straumann implants were placed in the second molar region, and the prosthesis was modified to accommodate implant retained ball attachments. Strain gages were incorporated into the fitting surface of both the framework and acrylic to measure microstrain (μStrain). The IARPD was loaded to 120Ns unilaterally and bilaterally in three different loading positions. Statistical analysis was carried out using SPSS version 18.0 (SPSS, Inc., Chicago, IL, USA) with an alpha level of 0.05 to compare the maximum μStrain values of the different loading conditions. Results. During unilateral and bilateral loading the maximum μStrain was predominantly observed in a buccal direction. As the load was moved anteriorly the μStrain increased in the mesial area. Unilateral loading resulted in a twisting of the structure and generated a strain mismatch between the metal and acrylic surfaces. Conclusions. Unilateral loading created lateral and vertical displacement of the IARPD. The curvature of the dental arch resulted in a twisting action which intensified as the unilateral load was moved anteriorly. PMID:23737788

  4. Designing cobalt chromium removable partial dentures for patients with shortened dental arches: a pilot survey.

    PubMed

    Nassani, M Z; Devlin, H; Tarakji, B; McCord, J F

    2011-08-01

    The aim of this survey was to investigate the quality of prescription for the fabrication of cobalt chromium removable partial dentures (RPDs) that are used to extend the shortened dental arches (SDAs). A survey of four commercial dental laboratories located in northern England was conducted. The target of this survey was cobalt chromium RPDs that were requested to restore SDAs comprising the anterior teeth and 2-4 premolars. Dentists' prescriptions were scrutinised, and a special data collection form was completed accordingly. A total of 94 dentists' prescriptions and associated SDA casts were examined. Almost all the requested cobalt chromium RPDs were clasp-retained RPDs (97%). Scrutinising the 91 prescriptions for clasp-retained cobalt chromium RPDs showed that dentists' prescriptions did not have any instructions about the design of the partial denture in a considerable proportion of the cases (32%). Teeth to be clasped were identified clearly in 45% of the prescriptions. A majority of the dentists (64%) failed to provide any instructions about the design of the rests to be placed on the most posterior premolar abutment teeth. A considerable proportion of the dentists delegated the task of selecting the type of the major connector to the dental technician (41%). Only 21 (23%) of the examined casts had clearly defined rest seat preparation. The outcome of this pilot survey shows inadequate quality of prescription in designing RPDs for patients with SDAs. This finding has an ethical and clinical bearing and does not fit with current legal guidelines relevant to designing RPDs. PMID:21175736

  5. Influence of working side contacts on masticatory function for mandibular distal extension removable partial dentures.

    PubMed

    Sueda, S; Fueki, K; Sato, S; Sato, H; Shiozaki, T; Kato, M; Ohyama, T

    2003-03-01

    The aim of this study was to clarify the influence of working side contacts for masticatory function for a distal extension removable partial denture. Five subjects who had edentulous arches from second premolar to second molar opposing natural teeth participated. Working side contacts were altered by using three types of artificial teeth attached to the denture base. A-form teeth made contact with opposite teeth while acting as the working side in a lateral excursion. The cusp angles of B- and C-form teeth were decreased by 10 degrees and 20 degrees, respectively compared with A-form teeth. B-and C-form teeth discluded with opposite teeth on the working side. Subjects were asked to perform two kinds of masticatory performance test. Obtained data were evaluated by the repeated-measures anova and the Tukey test for multiple comparisons. Results revealed that there was a significant difference (P=0.001) in the three types of teeth in the mixing ability test and the value of A-form teeth was statistically less value than those of the other teeth. However, there was no significant difference in the comminuting ability test. These results suggested that working side contacts between artificial teeth and opposite natural teeth influenced mixing ability, but not comminuting ability. PMID:12588504

  6. Survival of abutment teeth used for telescopic abutment retainers in removable partial dentures.

    PubMed

    Dittmann, Britta; Rammelsberg, Peter

    2008-01-01

    This retrospective clinical study investigated the survival of 385 abutment teeth retaining 117 removable partial dentures with 3 types of telescopic abutment retainers. Within a mean service time of 6.26 years, 8.8% of 385 abutment teeth were extracted. Cox regression analysis revealed a significantly higher risk of tooth loss for posterior teeth (odds ratio: 2.985) and for teeth with root canal treatment (odds ratio: 3.298), whereas age, sex, and number and type of telescopic retainer had no influence on survival. Root canal-treated teeth did not show a higher fracture rate, excluding this as an explanation for an increased risk of tooth loss. PMID:18717090

  7. Impression Procedures for Metal Frame Removable Partial Dentures as Applied by General Dental Practitioners.

    PubMed

    Fokkinga, Wietske A; van Uchelen, Judith; Witter, Dick J; Mulder, Jan; Creugers, Nico H J

    2016-01-01

    This pilot study analyzed impression procedures for conventional metal frame removable partial dentures (RPDs). Heads of RPD departments of three dental laboratories were asked to record features of all incoming impressions for RPDs during a 2-month period. Records included: (1) impression procedure, tray type (stock/custom), impression material (elastomer/alginate), use of border-molding material (yes/no); and (2) RPD type requested (distal-extension/tooth-bounded/combination). Of the 132 total RPD impressions, 111 (84%) involved custom trays, of which 73 (55%) were combined with an elastomer. Impression border-molding material was used in 4% of the cases. Associations between impression procedure and RPD type or dentists' year/university of graduation were not found. PMID:26929957

  8. A Technique to Facilitate Tooth Modification for Removable Partial Denture Prosthesis Guide Planes.

    PubMed

    Haeberle, C Brent; Abreu, Amara; Metzler, Kurt

    2016-07-01

    The technique in this article was developed to provide a means to create prepared guide planes of proper dimension to ensure a more stable and retentive removable partial denture prosthesis (RPDP) framework when providing this service for a patient. Using commonly found clinical materials, a paralleling device can be fabricated from the modified diagnostic cast of the patient's dental arch requiring an RPDP. Polymethyl methacrylate or composite added to an altered thermoplastic form can be positioned intraorally and used as a guide to predictably adjust tooth structure for guide planes. Since it can potentially minimize the number of impressions and diagnostic casts made during the procedure, this can help achieve the desired result more efficiently and quickly for the patient. PMID:26215216

  9. An ontology-driven, case-based clinical decision support model for removable partial denture design.

    PubMed

    Chen, Qingxiao; Wu, Ji; Li, Shusen; Lyu, Peijun; Wang, Yong; Li, Miao

    2016-01-01

    We present the initial work toward developing a clinical decision support model for specific design of removable partial dentures (RPDs) in dentistry. We developed an ontological paradigm to represent knowledge of a patient's oral conditions and denture component parts. During the case-based reasoning process, a cosine similarity algorithm was applied to calculate similarity values between input patients and standard ontology cases. A group of designs from the most similar cases were output as the final results. To evaluate this model, the output designs of RPDs for 104 randomly selected patients were compared with those selected by professionals. An area under the curve of the receiver operating characteristic (AUC-ROC) was created by plotting true-positive rates against the false-positive rate at various threshold settings. The precision at position 5 of the retrieved cases was 0.67 and at the top of the curve it was 0.96, both of which are very high. The mean average of precision (MAP) was 0.61 and the normalized discounted cumulative gain (NDCG) was 0.74 both of which confirmed the efficient performance of our model. All the metrics demonstrated the efficiency of our model. This methodology merits further research development to match clinical applications for designing RPDs. This paper is organized as follows. After the introduction and description of the basis for the paper, the evaluation and results are presented in Section 2. Section 3 provides a discussion of the methodology and results. Section 4 describes the details of the ontology, similarity algorithm, and application. PMID:27297679

  10. Influence of implant inclination associated with mandibular class I removable partial denture.

    PubMed

    de Freitas Santos, Ciandrus Moraes; Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; de Moraes, Sandra Lúcia Dantas; Falcón-Antenucci, Rosse Mary

    2011-03-01

    The aim of this study was to use two-dimensional finite element method to evaluate the displacement and stress distribution transmitted by a distal extension removable partial denture (DERPD) associated with an implant placed at different inclinations (0, 5, 15, and 30 degrees) in the second molar region of the edentulous mandible ridge. Six hemimandibular models were created: model A, only with the presence of the natural tooth 33; model B, similar to model A, with the presence of a conventional DERPD replacing the missing teeth; model C, similar to the previous model, with a straight implant (0 degrees) in the distal region of the ridge, under the denture base; model D, similar to model C, with the implant angled at 5 degrees in the mesial direction; model E, similar to model C, with the implant angled at 15 degrees in the mesial direction; and model F, similar to ME, with the implant angled at 30 degrees in the mesial direction. The models were created with the use of the AutoCAD 2000 program (Autodesk, Inc, San Rafael, CA) and processed for finite element analysis by the ANSYS 8.0 program (Swanson Analysis Systems, Houston, PA). The force applied was vertical of 50 N on each cusp tip. The results showed that the introduction of the RPD overloaded the supporting structures of the RPD and that the introduction of the implant helped to relieve the stresses of the mucosa alveolar, cortical bone, and trabecular bone. The best stress distribution occurred in model D with the implant angled at 5 degrees. The use of an implant as a support decreased the displacement of alveolar mucosa for all inclinations simulated. The stress distribution transmitted by the DERPD to the supporting structures was improved by the use of straight or slightly inclined implants. According to the displacement analysis and von Mises stress, it could be expected that straight or slightly inclined implants do not represent biomechanical risks to use. PMID:21415633

  11. An ontology-driven, case-based clinical decision support model for removable partial denture design

    PubMed Central

    Chen, Qingxiao; Wu, Ji; Li, Shusen; Lyu, Peijun; Wang, Yong; Li, Miao

    2016-01-01

    We present the initial work toward developing a clinical decision support model for specific design of removable partial dentures (RPDs) in dentistry. We developed an ontological paradigm to represent knowledge of a patient’s oral conditions and denture component parts. During the case-based reasoning process, a cosine similarity algorithm was applied to calculate similarity values between input patients and standard ontology cases. A group of designs from the most similar cases were output as the final results. To evaluate this model, the output designs of RPDs for 104 randomly selected patients were compared with those selected by professionals. An area under the curve of the receiver operating characteristic (AUC-ROC) was created by plotting true-positive rates against the false-positive rate at various threshold settings. The precision at position 5 of the retrieved cases was 0.67 and at the top of the curve it was 0.96, both of which are very high. The mean average of precision (MAP) was 0.61 and the normalized discounted cumulative gain (NDCG) was 0.74 both of which confirmed the efficient performance of our model. All the metrics demonstrated the efficiency of our model. This methodology merits further research development to match clinical applications for designing RPDs. This paper is organized as follows. After the introduction and description of the basis for the paper, the evaluation and results are presented in Section 2. Section 3 provides a discussion of the methodology and results. Section 4 describes the details of the ontology, similarity algorithm, and application. PMID:27297679

  12. [Prevention: the success of a partial denture].

    PubMed

    van Loveren, C

    2009-11-01

    After the placement of removable partial dentures, additional caries and periodontal problems may arise in the remaining dentition. These problems are the result of insufficient oral hygiene. Oral hygiene may be hampered by wearing the removable partial denture. The design of the removable partial denture should be carried out according to modern concepts of preventive dentistry. Before placing a removable partial denture, the patient's mouth should be thoroughly healthy and the patient should be instructed properly on adequate oral care. Furthermore, the patient should be aware of his/her own responsibility for maintenance. If cleaning twice a day with fluoride tooth-paste provides insufficient protection, care can be supported by daily use of a fluoride containing antimicrobial mouthrinse. Little effect can be expected from professionally applied fluoride or chlorhexidine solutions. PMID:19999672

  13. [Quantitative and qualitative analysis of oral microbiota by orthopedic rehabilitation with full and partial removable dentures].

    PubMed

    Stafeev, A A; Chesnokova, M G; Chesnokov, V A

    2015-01-01

    Microbiological analysis of biomaterial surface in dental prosthesis showed the most common colonizing gram-positive species to be S. aureus, Micrococcus spp., S. haemolyticus, E. faecalis, mainly massive colonization with S. aureus was seen. The highest concentration of C. albicans colonization was found in removable dentures and may have a destructive effect on prosthetic material. PMID:26953429

  14. A technique for retrofitting a metal ceramic crown to an attachment-retained removable partial denture: a clinical report.

    PubMed

    Uludag, Bulent; Gonuldas, Fehmi; Tokar, Emre; Sahin, Volkan

    2015-02-01

    In dental applications, precision attachments have been used to retain removable partial dentures (RPDs) for several decades. Various types of extracoronal attachments are commonly used in combination with fixed partial dentures and RPDs to achieve retention and stability. Fracture of the framework, fracture of the roots or teeth, and irretrievable decrease of retention are common reasons for a failed attachment-retained RPD. Another complication of metal ceramic crowns with precision attachment is decementation of the crowns. When fixed components of the attachment-retained RPD fail, the traditional treatment approach requires remaking both the fixed and removable components of the attachment-retained RPD. This technique describes retrofitting of a metal ceramic crown to a resilient attachment-retained RPD. PMID:25066428

  15. A comparative study of the centrifugal and vacuum-pressure techniques of casting removable partial denture frameworks.

    PubMed

    Shanley, J J; Ancowitz, S J; Fenster, R K; Pelleu, G B

    1981-01-01

    A study was undertaken to evaluate two techniques for casting accuracy on removable partial denture frameworks: centrifugal casting and vacuum-pressure casting. A standard metal die with predetermined reference points in a horizontal plane was duplicated in refractory investment. The casts were waxed, and castings of nickel-chrome alloy were fabricated by the two techniques. Both the casts and the castings were measured between the reference points with a measuring microscope. With both casting methods, the differences between the casts and the castings were significant, but no significant differences were found between castings produced by the two techniques. Vertical measurements at three designated points also showed no significant differences between the castings. Our findings indicate that dental laboratories should be able to use the vacuum-pressure method of casting removable partial denture frameworks and achieve accuracy similar to that obtained by the centrifugal method of casting. PMID:7007622

  16. Evaluation of Team-Based Learning and Traditional Instruction in Teaching Removable Partial Denture Concepts.

    PubMed

    Echeto, Luisa F; Sposetti, Venita; Childs, Gail; Aguilar, Maria L; Behar-Horenstein, Linda S; Rueda, Luis; Nimmo, Arthur

    2015-09-01

    The aim of this study was to evaluate the effectiveness of team-based learning (TBL) methodology on dental students' retention of knowledge regarding removable partial denture (RPD) treatment. The process of learning RPD treatment requires that students first acquire foundational knowledge and then use critical thinking skills to apply that knowledge to a variety of clinical situations. The traditional approach to teaching, characterized by a reliance on lectures, is not the most effective method for learning clinical applications. To address the limitations of that approach, the teaching methodology of the RPD preclinical course at the University of Florida was changed to TBL, which has been shown to motivate student learning and improve clinical performance. A written examination was constructed to compare the impact of TBL with that of traditional teaching regarding students' retention of knowledge and their ability to evaluate, diagnose, and treatment plan a partially edentulous patient with an RPD prosthesis. Students taught using traditional and TBL methods took the same examination. The response rate (those who completed the examination) for the class of 2013 (traditional method) was 94% (79 students of 84); for the class of 2014 (TBL method), it was 95% (78 students of 82). The results showed that students who learned RPD with TBL scored higher on the examination than those who learned RPD with traditional methods. Compared to the students taught with the traditional method, the TBL students' proportion of passing grades was statistically significantly higher (p=0.002), and 23.7% more TBL students passed the examination. The mean score for the TBL class (0.758) compared to the conventional class (0.700) was statistically significant with a large effect size, also demonstrating the practical significance of the findings. The results of the study suggest that TBL methodology is a promising approach to teaching RPD with successful outcomes. PMID:26329028

  17. Shape Optimization for Additive Manufacturing of Removable Partial Dentures--A New Paradigm for Prosthetic CAD/CAM.

    PubMed

    Chen, Junning; Ahmad, Rohana; Suenaga, Hanako; Li, Wei; Sasaki, Keiichi; Swain, Michael; Li, Qing

    2015-01-01

    With ever-growing aging population and demand for denture treatments, pressure-induced mucosa lesion and residual ridge resorption remain main sources of clinical complications. Conventional denture design and fabrication are challenged for its labor and experience intensity, urgently necessitating an automatic procedure. This study aims to develop a fully automatic procedure enabling shape optimization and additive manufacturing of removable partial dentures (RPD), to maximize the uniformity of contact pressure distribution on the mucosa, thereby reducing associated clinical complications. A 3D heterogeneous finite element (FE) model was constructed from CT scan, and the critical tissue of mucosa was modeled as a hyperelastic material from in vivo clinical data. A contact shape optimization algorithm was developed based on the bi-directional evolutionary structural optimization (BESO) technique. Both initial and optimized dentures were prototyped by 3D printing technology and evaluated with in vitro tests. Through the optimization, the peak contact pressure was reduced by 70%, and the uniformity was improved by 63%. In vitro tests verified the effectiveness of this procedure, and the hydrostatic pressure induced in the mucosa is well below clinical pressure-pain thresholds (PPT), potentially lessening risk of residual ridge resorption. This proposed computational optimization and additive fabrication procedure provides a novel method for fast denture design and adjustment at low cost, with quantitative guidelines and computer aided design and manufacturing (CAD/CAM) for a specific patient. The integration of digitalized modeling, computational optimization, and free-form fabrication enables more efficient clinical adaptation. The customized optimal denture design is expected to minimize pain/discomfort and potentially reduce long-term residual ridge resorption. PMID:26161878

  18. Shape Optimization for Additive Manufacturing of Removable Partial Dentures - A New Paradigm for Prosthetic CAD/CAM

    PubMed Central

    2015-01-01

    With ever-growing aging population and demand for denture treatments, pressure-induced mucosa lesion and residual ridge resorption remain main sources of clinical complications. Conventional denture design and fabrication are challenged for its labor and experience intensity, urgently necessitating an automatic procedure. This study aims to develop a fully automatic procedure enabling shape optimization and additive manufacturing of removable partial dentures (RPD), to maximize the uniformity of contact pressure distribution on the mucosa, thereby reducing associated clinical complications. A 3D heterogeneous finite element (FE) model was constructed from CT scan, and the critical tissue of mucosa was modeled as a hyperelastic material from in vivo clinical data. A contact shape optimization algorithm was developed based on the bi-directional evolutionary structural optimization (BESO) technique. Both initial and optimized dentures were prototyped by 3D printing technology and evaluated with in vitro tests. Through the optimization, the peak contact pressure was reduced by 70%, and the uniformity was improved by 63%. In vitro tests verified the effectiveness of this procedure, and the hydrostatic pressure induced in the mucosa is well below clinical pressure-pain thresholds (PPT), potentially lessening risk of residual ridge resorption. This proposed computational optimization and additive fabrication procedure provides a novel method for fast denture design and adjustment at low cost, with quantitative guidelines and computer aided design and manufacturing (CAD/CAM) for a specific patient. The integration of digitalized modeling, computational optimization, and free-form fabrication enables more efficient clinical adaptation. The customized optimal denture design is expected to minimize pain/discomfort and potentially reduce long-term residual ridge resorption. PMID:26161878

  19. Effect of different cleansers on the surface of removable partial denture.

    PubMed

    Felipucci, Daniela Nair Borges; Davi, Letícia Resende; Paranhos, Helena Freitas Oliveira; Bezzon, Osvaldo Luiz; Silva, Rodrigo Ferreira; Pagnano, Valéria Oliveira

    2011-01-01

    Removable partial dentures (RPD) demand specific hygienic cleaning and the combination of brushing with immersion in chemical solutions has been the most recommended method for control of biofilm. However, the effect of the cleansers on metallic components has not been widely investigated. This study evaluated the effect of different cleansers on the surface of RPD. Five disc specimens (12 mm x 3 mm metallic disc centered in a 38 x 18 x 4 mm mould filled with resin) were obtained for each experimental situation: 6 solutions [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) control] and 2 Co-Cr alloys [DeguDent (DD) and VeraPDI (VPDI)] were used for each experimental situation. A 180-day immersion was simulated and the measurements of roughness (Ra, µm) of metal and resin were analyzed using 2-way ANOVA and Tukey's test. The surface changes and tarnishes were examined with a scanning electronic microscopy (SEM). In addition, energy dispersive x-ray spectrometry (EDS) analysis was carried out at representative areas. Visually, NaOCl and MI specimens presented surface tarnishes. The roughness of materials was not affected by the solutions (p>0.05). SEM images showed that NaOCl and MI provided surface changes. EDS analysis revealed the presence of oxygen for specimens in contact with both MI and NaOCl solutions, which might suggest that the two solutions promoted the oxidation of the surfaces, thus leading to spot corrosion. Within the limitations of this study, it may be concluded that the NaOCl and MI may not be suitable for cleaning of RPD. PMID:22011895

  20. A Combination of Various Technologies in the Fabrication of a Removable Partial Denture--A Case Study.

    PubMed

    Seitz, Stefanie; Cox, Nicholas; Jones, John D; Zimmermann, Richard

    2016-01-01

    Digital dentistry is increasing prevalent throughout general dental practice. Scanned impression systems, CAD/CAM software, milling units, and 3D printers are becoming used with regularity by some private practitioners. This case report describes a combination of multiple technologies including intraoral scanning, 3D printing, and traditional impression and processing techniques used for fabricating a removable partial denture. The patient indicated that he was highly satisfied throughout the course of treatment and especially with the final result. Future technology will continue to evolve and be more widely used in removable prosthodontics and other areas of dentistry. PMID:27008841

  1. A field survey of the partially edentate elderly: Investigation of factors related to the usage rate of removable partial dentures.

    PubMed

    Murai, S; Matsuda, K; Ikebe, K; Enoki, K; Hatta, K; Fujiwara, K; Maeda, Y

    2015-11-01

    Although the shortened dental arch (SDA) concept has been known to all over the world, acceptance of the SDA concept as an oral health standard can be questionable from the patients' point of view, even if it is biologically reasonable. Furthermore, because the health insurance system covers removable partial dentures (RPDs) for all citizens in Japan, SDA patients seem to prefer to receive prosthetic treatment to replace the missing teeth. However, there were few field surveys to investigate the usage rate of RPDs in Japan. The purpose of this study was to determine the usage rate of RPDs in older Japanese subjects and to investigate the factors related to the usage of RPDs. Partially edentate participants (n = 390) were included in this study. Oral examinations were conducted to record several indices. The Cochran-Armitage trend test was used to evaluate the relationship between the number of missing teeth and the usage rate of RPDs. Chi-squared tests and logistic regression analysis were conducted to evaluate the factors related to the usage rate of RPDs. Usage of RPDs had a significantly positive association with the number of missing distal extension teeth and bilaterally missing teeth. The usage rate of RPDs increased as the number of missing distal extension teeth increased (P for trend < 0·001). The conclusion of this study was that participants with missing distal extension teeth had higher usage rates of RPDs than other participants, and the usage rate increased as the number of missing distal extension teeth increased. PMID:26059645

  2. Implant-Supported Removable Partial Denture Improves the Quality of Life of Patients with Extreme Tooth Loss.

    PubMed

    Campos, Camila Heitor; Gonçalves, Thais Marques Simek Vega; Garcia, Renata Cunha Matheus Rodrigues

    2015-10-01

    This study aimed to evaluate oral health-related quality of life (OHRQoL) in partially dentate subjects, presenting extreme tooth loss in posterior region with missing post-canines, comparing the use of conventional removable partial dentures (RPDs) and implant-supported RPDs. OHRQoL was measured using the Brazilian version of the Oral Health Impact Profile. Twelve subjects presenting maxillary total and mandibular Kennedy Class I edentulism (mean age 62.6±7.8 years) first received complete maxillary dentures and conventional mandibular free-end RPDs. After two months, the subjects had their OHRQoL assessed. Osseointegrated implants were inserted bilaterally in the mandibular first molar regions, and after four months ball abutments were placed to support the free-end RPD. Two months later, the patients had their OHRQoL reassessed. Wilcoxon signed-rank test was used to evaluate differences in OHRQoL (α=0.05). Results showed improvement in all OHIP-49 domains (p<0.05) after associating implants to the RPD. The mandibular implant-supported free-end RPD significantly improved OHRQoL. PMID:26647929

  3. Effect of different cleansers on the weight and ion release of removable partial denture: an in vitro study

    PubMed Central

    FELIPUCCI, Daniela N.B.; DAVI, Letícia R.; PARANHOS, Helena F.O.; BEZZON, Osvaldo L.; SILVA, Rodrigo F.; BARBOSA JUNIOR, Fernando; PAGNANO, Valéria O.

    2011-01-01

    Objective Removable partial dentures (RPD) require different hygiene care, and association of brushing and chemical cleansing is the most recommended to control biofilm formation. However, the effect of cleansers has not been evaluated in RPD metallic components. The aim of this study was to evaluate in vitro the effect of different denture cleansers on the weight and ion release of RPD. Material and Methods Five specimens (12x3 mm metallic disc positioned in a 38x18x4 mm mould filled with resin), 7 cleanser agents [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) (control)] and 2 cobalt-chromium alloys [DeguDent (DD), and VeraPDI (VPDI)] were used for each experimental situation. One hundred and eighty immersions were performed and the weight was analyzed with a high precision analytic balance. Data were recorded before and after the immersions. The ion release was analyzed using mass spectrometry with inductively coupled plasma. Data were analyzed by two-way ANOVA and Tukey HSD post hoc test at 5% significance level. Results Statistical analysis showed that CT and MI had higher values of weight loss with higher change in VPDI alloy compared to DD. The solutions that caused more ion release were NaOCl and MI. Conclusions It may be concluded that 0.05% NaOCl and Medical Interporous tablets are not suitable as auxiliary chemical solutions for RPD care. PMID:21986653

  4. The influence of removable partial dentures on the periodontal health of abutment and non-abutment teeth

    PubMed Central

    Dula, Linda J.; Shala, Kujtim Sh.; Pustina–Krasniqi, Teuta; Bicaj, Teuta; Ahmedi, Enis F.

    2015-01-01

    Objective: The aim of this study was to evaluate the influence of removable partial dentures (RPD) on the periodontal health of abutment and non-abutment teeth. Materials and Methods: A total 107 patients with RPD participated in this study. It was examined 138 RPD, they were 87 with clasp-retained and 51 were RPD with attachments. The following periodontal parameters were evaluated for abutment and non-abutment teeth, plaque index (PLI), calculus index (CI), bleeding on probing (BOP), probing depth (PD) (mm) and tooth mobility (TM) index. These clinical measurements were taken immediately before insertion the RPD, then one and 3 months after insertion. The level of significance was set at (P < 0.05). Results: The mean scores for PLI, CI, BOP, PD, and TM index, of the abutment teeth and non-abutment teeth were no statistically significant at the time of insertion of RPD. After 1-month, PLI was statistically significant (0.57 ± 0.55 for abutment and 0.30 ± 0.46 for non-abutment teeth). After 3 months, there were significant differences between abutment and non-abutment teeth with regard to the BOP (1.53 ± 0.50 and 1.76 ± 0.43 respectively), PD (0.28 ± 0.45 and 0.12 ± 0.33 respectively) and PLI (1.20 ± 0.46 and 0.75 ± 0.64 respectively). No significant mean difference in TM and CI was found between the abutment and non-abutment teeth (P > 0.05). Conclusions: With carefully planned prosthetic treatment and adequate maintenance of the oral and denture hygiene, we can prevent the periodontal diseases. PMID:26430367

  5. Influence of Implant Position on Stress Distribution in Implant-Assisted Distal Extension Removable Partial Dentures: A 3D Finite Element Analysis

    PubMed Central

    Memari, Yeganeh; Geramy, Allahyar; Fayaz, Amir; Rezvani Habib Abadi, Shirin; Mansouri, Yasaman

    2014-01-01

    Objective: Distal extension removable partial denture is a prosthesis with lack of distal dental support with a 13-fold difference in resiliency between the mucosa and the periodontal ligament, resulting in leverage during compression forces. It may be potentially destructive to the abutments and the surrounding tissues. The aim of this study was to assess the effect of implant location on stress distribution, in distal extension implant assisted removable partial dentures. Materials and Methods: Three-dimensional models of a bilateral distal extension partially edentulous mandible containing anterior teeth and first premolar in both sides of the arch, a partial removable denture and an implant (4×10mm) were designed. With the aid of the finite element program ANSYS 8.0, the models were meshed and strictly vertical forces of 10 N were applied to each cusp tip. Displacement and von Mises Maps were plotted for visualization of results. Results: When an implant was placed in the second premolar region, the highest stress on implant, abutment tooth and cancellous bone was shown. The lowest stress was shown on implant and bone in the 1st molar area. Conclusion: Implants located in the first molar area showed the least distribution of stresses in the analyzed models. PMID:25628678

  6. Influence of ridge inclination and implant localization on the association of mandibular Kennedy class I removable partial denture.

    PubMed

    Cunha, Lígia Del' Arco Pignatta; Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; Falcón-Antenucci, Rosse Mary; Goiato, Marcelo Coelho

    2011-05-01

    The aim of this study was to evaluate the tendency of displacement of the supporting structures of the distal extension removable partial denture (DERPD) associated to the implant with different inclinations of alveolar ridge and implant localizations through a two-dimensional finite-element method. Sixteen mandibular models were fabricated, presenting horizontal, distally descending, distally ascending, or descending-ascending ridges. All models presented the left canine and were rehabilitated with conventional DERPD or implant-retained prosthesis with the ERA system. The models were obtained by the AutoCAD software and transferred to the finite-element software ANSYS 9.0 for analysis. A force of 50 N was applied on the cusp tips of the teeth, with 5 points of loading of 10 N. The results were visualized by displacement maps. For all ridge inclinations, the assembly of the DERPD with distal plate retained by an anterior implant exhibited the lowest requisition of the supporting structures. The highest tendency of displacement occurred in the model with distally ascending ridge with incisal rest. It was concluded that the association of the implant decreased the displacement of the DERPD, and the anterior positioning of the implant associated to the DERPD with the distal plate preserved the supporting structures for all ridges. PMID:21558932

  7. Three Dimensional Finite Element Analysis of Distal Abutment Stresses of Removable Partial Dentures with Different Retainer Designs

    PubMed Central

    Zarrati, Simindokht; Heidari, Fatemeh; Kashani, Jamal

    2015-01-01

    Objectives: This finite element method study aimed to compare the amount of stress on an isolated mandibular second premolar in two conventional reciprocal parallel interface designs of removable partial dentures (RPDs) and the same RPD abutment tooth (not isolated). Materials and Methods: A Kennedy Class 1, modification 1 RPD framework was simulated on a 3D model of mandible with three different designs: an isolated tooth with a mesial rest, an isolated tooth with mesial and distal rests and an abutment with a mesial rest (which was not isolated); 26 N occlusal forces were exerted bilaterally on the first molar sites. Stress on the abutment teeth was analyzed using Cosmos Works 2009 Software. Results: In all designs, the abutment tooth stress concentration was located in the buccal alveolar crest. In the first model, the von Mises stress distribution in the contact area of I-bar clasp and cervical portion of the tooth was 19 MPa and the maximum stress was 30 MPa. In the second model, the maximum von Mises stress distribution was 15 MPa in the cervical of the tooth. In the third model, the maximum von Mises stress was located in the cervical of the tooth and the distal proximal plate. Conclusion: We recommend using both mesial and distal rests on the distal abutment teeth of distal extension RPDs. The abutment of an extension base RPD, which is not isolated in presence of its neighboring more anterior tooth, may have a better biomechanical prognosis. PMID:26884772

  8. The effect of four sprue shapes on the quality of cobalt-chromium cast removable partial denture frame-works

    PubMed Central

    Viswambaran, M.; Agarwal, S. K.

    2013-01-01

    Statement of Problem: Sprue design is a factor that controls the velocity and adequate supply of metal to the mould. Currently various manufacturers recommend different shapes of sprue, which have not been advocated in textbooks and literature is lacking for their routine applications. Purpose: This in vitro study was carried out to determine the efficacy of four sprue shapes in producing complete, void free cobalt-chrome removable partial denture frameworks. Materials and Methods: A brass metal die with a Kennedy class III, modification 1, partially edentulous arch was used and four sprue shapes (Group A-Ribbon, Group B-Square, Group C-Round and Group D- Round with reservoir) were evaluated. 40 refractory casts were made, 10 wax patterns for each sprue design were waxed up, invested with phosphate bonded investment material and castings done with induction casting machine by the same operator under standardized protocols. The cast frameworks were evaluated for 1. The defects observed visually before finishing and polishing procedures, 2. Fit on the master die as seen with naked eye and 3. Defects on radiographic evaluation. Data were tabulated and statistically analyzed with 1-way ANOVA followed by Student ‘t’ test. Results: The results differed significantly (P < 0.0001) between the Groups with maximum defects in the castings of Group A followed in decreasing order by Group B, Group C and Group D. When comparing between the Groups (P < 0.05), the defects in Groups C and D was significantly lower than Group A and Group B. Conclusions: Round sprues with reservoir produced most satisfactory fit of castings with minimum number of internal and external defects. PMID:24014998

  9. Effect of the Number of Implants on Stress Distribution of Anterior Implant-Supported Fixed Prostheses Combined with a Removable Partial Denture: A Finite Element Analysis

    PubMed Central

    Mahshid, Minoo; Geramy, Allahyar; Ejlali, Massoud; Sedaghat Monfared, Majid; Rezvani Habib Abadi, Shirin

    2014-01-01

    Objective: The main goal of this study was to evaluate differences in stress distribution relevant to the number of implants under an anterior bridge when combined with a removable partial denture in the posterior region. Materials and Methods: Four three-dimensional finite element models (3D FEM) were designed from a mandible containing an implant-supported bridge extending between canines, and a bilateral distal extension removable partial denture. A nonrigid connection was selected as the attachment method between the partial denture and the anterior implant-supported fixed prosthesis; 2, 3, 4 and 5 implants supporting the bridge all with 10mm length and 3.8 mm diameter were assessed. With the aid of the finite element program ANSYS 8.0, the models were loaded and von Mises stresses were evaluated. Results: In spongy bone, stress forces showed a decrease from 2 implants to 4 implants but showed an increase in the 5-implant model. Stresses on cortical bone of terminal implants were in similar range in the 2-, 3- and 4-implant models. While, in the 5-implant model the amount of stresses on terminal implants increased dramatically. The stresses on implants were nearly similar in all models, with the greatest amount on terminal implants. Conclusion: Within the limitations of this study, 2-, 3- and 4-implant models showed less stress on cortical and spongy bone in comparison with the 5-implant model. The stresses transferred to implants were nearly similar. PMID:25628669

  10. The path of placement of a removable partial denture: a microscope based approach to survey and design

    PubMed Central

    2015-01-01

    This article reviews the topic of how to identify and develop a removable partial denture (RPD) path of placement, and provides a literature review of the concept of the RPD path of placement, also known as the path of insertion. An optimal RPD path of placement, guided by mutually parallel guide planes, ensures that the RPD flanges fit intimately over edentulous ridge structures and that the framework fits intimately with guide plane surfaces, which prevents food collecting empty spaces between the intaglio surface of the framework and intraoral surfaces, and ensures that RPD clasps engage adequate numbers of tooth undercuts to ensure RPD retention. The article covers topics such as the causes of obstructions to RPD intra-oral seating, the causes of food collecting empty spaces that may exist around an RPD, and how to identify if a guide plane is parallel with the projected RPD path of placement. The article presents a method of using a surgical operating microscope, or high magnification (6-8x or greater) binocular surgical loupes telescopes, combined with co-axial illumination, to identify a preliminary path of placement for an arch. This preliminary path of placement concept may help to guide a dentist or a dental laboratory technician when surveying a master cast of the arch to develop an RPD path of placement, or in verifying that intra-oral contouring has aligned teeth surfaces optimally with the RPD path of placement. In dentistry, a well-fitting RPD reduces long-term periodontal or structural damage to abutment teeth. PMID:25722842

  11. The path of placement of a removable partial denture: a microscope based approach to survey and design.

    PubMed

    Mamoun, John Sami

    2015-02-01

    This article reviews the topic of how to identify and develop a removable partial denture (RPD) path of placement, and provides a literature review of the concept of the RPD path of placement, also known as the path of insertion. An optimal RPD path of placement, guided by mutually parallel guide planes, ensures that the RPD flanges fit intimately over edentulous ridge structures and that the framework fits intimately with guide plane surfaces, which prevents food collecting empty spaces between the intaglio surface of the framework and intraoral surfaces, and ensures that RPD clasps engage adequate numbers of tooth undercuts to ensure RPD retention. The article covers topics such as the causes of obstructions to RPD intra-oral seating, the causes of food collecting empty spaces that may exist around an RPD, and how to identify if a guide plane is parallel with the projected RPD path of placement. The article presents a method of using a surgical operating microscope, or high magnification (6-8x or greater) binocular surgical loupes telescopes, combined with co-axial illumination, to identify a preliminary path of placement for an arch. This preliminary path of placement concept may help to guide a dentist or a dental laboratory technician when surveying a master cast of the arch to develop an RPD path of placement, or in verifying that intra-oral contouring has aligned teeth surfaces optimally with the RPD path of placement. In dentistry, a well-fitting RPD reduces long-term periodontal or structural damage to abutment teeth. PMID:25722842

  12. Evaluation of different retention systems on a distal extension removable partial denture associated with an osseointegrated implant.

    PubMed

    Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; Falcón-Antenucci, Rosse Mary; Goiato, Marcelo Coelho; Gennari Filho, Humberto

    2010-05-01

    The aim of this study was to evaluate the biomechanical behavior of a mandibular distal extension removable partial denture (DERPD) associated with an implant and different retention system, by bidimensional finite element method. Five hemimandible models with a canine and external hexagon implant at second molar region associated with DERPD were simulated: model A, hemimandible with a canine and a DERPD; model B, hemimandible with a canine and implant with a healing abutment associated to a DERPD; model C, hemimandible with a canine and implant with an ERA attachment associated to a DERPD; model D, hemimandible with a canine and implant with an O'ring attachment associated to a DERPD; and model E, hemimandible with a canine and implant-supported prosthesis associated to a DERPD. Cusp tips were loaded with 50 N of axial or oblique force (45 degrees). Finite element analysis was performed in ANSYS 9.0. model E showed the higher displacement and overload in the supporting tissues; the patterns of stress distribution around the dental apex of models B, C, and D were similar. The association between a DERPD and an osseointegrated implant using the ERA or O'ring systems shows lower stress values. Oblique forces showed higher stress values and displacement. Oblique forces increased the displacement and stress levels in all models; model C displayed the best stress distribution in the supporting structures; healing abutment, ERA, and O'ring systems were viable with RPD, but DERPD association with a single implant-supported prosthesis was nonviable. PMID:20485037

  13. Effect of storage time and framework design on the accuracy of maxillary cobalt-chromium cast removable partial dentures

    PubMed Central

    Viswambaran, M.; Sundaram, R. K.

    2015-01-01

    Statement of Problem: Inaccuracies in the fit of palatal major connectors may be related to distortion of the wax pattern due to prolonged storage time and faulty major connector design. Purpose: This in vitro study was carried out to find out the effect of storage time and major connector design on the accuracy of cobalt-chromium cast removable partial dentures (RPDs). Materials and Methods: A brass metal die with a Kennedy Class III, modification 1, the partially edentulous arch was used as a master die. Thirty-six refractory casts were fabricated from the master die. The refractory casts were divided into three groups (Group I: Anterior-posterior palatal bar, Group II: Palatal strap and Group III: Palatal plate) based on the design of maxillary major connector and subdivided into four groups (sub Group A: 01 h, sub Group B: 03 h, Sub Group C: 06 h, and sub Group D: 24 h) based on the storage time. For each group, 12 frameworks were fabricated. The influence of wax pattern storage time and the accuracy of the fit palatal major connector designs on the master die were compared. Casting defects (nodules/incompleteness) of the frameworks were also evaluated before finishing and polishing. Repeated measures analysis of variance was used to analyze the data. Results: The gap discrepancy was least in sub Group A (01 h) followed by sub Group B (03 h) and C (06 h) and most in sub Group D (24 h). Statistically significant differences (P < 0.05 in all locations L1–L5) in the fit of the framework were related to the design of the major connector. The gap discrepancy was least in Group I (anterior-posterior palatal bar) followed by Group II (palatal strap) and most in Group II (palatal plate). Conclusions: It is recommended that the wax patterns for RPD to be invested immediately on completion of the wax procedure. The selection of a major connector design is crucial for an accurate fit of RPD. PMID:26681850

  14. Telescopic Partial Dentures-Concealed Technology.

    PubMed

    Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

    2015-09-01

    The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of "floating plastic" in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental implants or fixed partial denture is the better options, but they have certain limitations. However, overdentures and particularly telescopic denture is the overlooked technology in dentistry that would be a boon for such needy patients. Telescopic denture is especially indicated in the distal edentulous area with minimum two teeth bilaterally present with a good amount of periodontal support. This treatment modality is sort of preventive prosthodontics remedy, which in a conservative manner preserve the remaining teeth and helps in conservation of alveolar bone ultimately. There are two tenets related to this option, one is constant conservation edentulous ridge around the retained tooth and the most important is the endless existence of periodontal sensory action that directs and monitor gnathodynamic task. In this option the primary coping or inner coping are cemented on the prepared tooth, and a similar removable outer or inner telescopic crown placed tightly by using a mechanism of tenso-friction, this is firmly attached to a removable RPD in place without moving or rocking of the prosthesis, which is the common compliant of almost all patients of RPD. Copings are also protecting the abutment from tooth decay and also offers stabilization and maintaining of the outer crown. The outer crown engages the inner coping and gives as an anchor for the remainder of the dentition. This work is the review of telescopic prosthesis which is well supported by the case discussion, and

  15. Telescopic Partial Dentures-Concealed Technology

    PubMed Central

    Bhagat, Tushar Vitthalrao; Walke, Ashwini Nareshchandra

    2015-01-01

    The ideal goal of good dentist is to restore the missing part of oral structure, phonetics, his look and the most important is restored the normal health of the patient, which is hampered due to less or insufficient intake of food. Removable partial denture (RPD) treatment option is considered as a notion, which precludes the inevitability of “floating plastic” in edentulous mouth, that many times fail to fulfill the above essential of the patients. In modern dentistry, though the dental implants or fixed partial denture is the better options, but they have certain limitations. However, overdentures and particularly telescopic denture is the overlooked technology in dentistry that would be a boon for such needy patients. Telescopic denture is especially indicated in the distal edentulous area with minimum two teeth bilaterally present with a good amount of periodontal support. This treatment modality is sort of preventive prosthodontics remedy, which in a conservative manner preserve the remaining teeth and helps in conservation of alveolar bone ultimately. There are two tenets related to this option, one is constant conservation edentulous ridge around the retained tooth and the most important is the endless existence of periodontal sensory action that directs and monitor gnathodynamic task. In this option the primary coping or inner coping are cemented on the prepared tooth, and a similar removable outer or inner telescopic crown placed tightly by using a mechanism of tenso-friction, this is firmly attached to a removable RPD in place without moving or rocking of the prosthesis, which is the common compliant of almost all patients of RPD. Copings are also protecting the abutment from tooth decay and also offers stabilization and maintaining of the outer crown. The outer crown engages the inner coping and gives as an anchor for the remainder of the dentition. This work is the review of telescopic prosthesis which is well supported by the case discussion, and

  16. Prefabricated light-polymerizing plastic pattern for partial denture framework.

    PubMed

    Takaichi, Atsushi; Wakabayashi, Noriyuki; Igarashi, Yoshimasa

    2011-10-01

    Our aim is to report an application of a prefabricated light-polymerizing plastic pattern to construction of removable partial denture framework without the use of a refractory cast. A plastic pattern for the lingual bar was adapted on the master cast of a mandibular Kennedy class I partially edentulous patient. The pattern was polymerized in a light chamber. Cobalt-chromium wires were employed to minimize the potential distortion of the plastic framework. The framework was carefully removed from the master cast and invested with phosphate-bonded investment for the subsequent casting procedures. A retentive clasp was constructed using 19-gauge wrought wire and was welded to the framework by means of laser welding machine. An excellent fit of the framework in the patient's mouth was observed in the try-in and the insertion of the denture. The result suggests that this method minimizes laboratory cost and time for partial denture construction. PMID:22346178

  17. Prefabricated light-polymerizing plastic pattern for partial denture framework

    PubMed Central

    Takaichi, Atsushi; Wakabayashi, Noriyuki; Igarashi, Yoshimasa

    2011-01-01

    Our aim is to report an application of a prefabricated light-polymerizing plastic pattern to construction of removable partial denture framework without the use of a refractory cast. A plastic pattern for the lingual bar was adapted on the master cast of a mandibular Kennedy class I partially edentulous patient. The pattern was polymerized in a light chamber. Cobalt–chromium wires were employed to minimize the potential distortion of the plastic framework. The framework was carefully removed from the master cast and invested with phosphate-bonded investment for the subsequent casting procedures. A retentive clasp was constructed using 19-gauge wrought wire and was welded to the framework by means of laser welding machine. An excellent fit of the framework in the patient's mouth was observed in the try-in and the insertion of the denture. The result suggests that this method minimizes laboratory cost and time for partial denture construction. PMID:22346178

  18. Clinical application of removable partial dentures using thermoplastic resin. Part II: Material properties and clinical features of non-metal clasp dentures.

    PubMed

    Fueki, Kenji; Ohkubo, Chikahiro; Yatabe, Masaru; Arakawa, Ichiro; Arita, Masahiro; Ino, Satoshi; Kanamori, Toshikazu; Kawai, Yasuhiko; Kawara, Misao; Komiyama, Osamu; Suzuki, Tetsuya; Nagata, Kazuhiro; Hosoki, Maki; Masumi, Shin-ichi; Yamauchi, Mutsuo; Aita, Hideki; Ono, Takahiro; Kondo, Hisatomo; Tamaki, Katsushi; Matsuka, Yoshizo; Tsukasaki, Hiroaki; Fujisawa, Masanori; Baba, Kazuyoshi; Koyano, Kiyoshi; Yatani, Hirofumi

    2014-04-01

    This position paper reviews physical and mechanical properties of thermoplastic resin used for non-metal clasp dentures, and describes feature of each thermoplastic resin in clinical application of non-metal clasp dentures and complications based on clinical experience of expert panels. Since products of thermoplastic resin have great variability in physical and mechanical properties, clinicians should utilize them with careful consideration of the specific properties of each product. In general, thermoplastic resin has lower color-stability and higher risk for fracture than polymethyl methacrylate. Additionally, the surface of thermoplastic resin becomes roughened more easily than polymethyl methacrylate. Studies related to material properties of thermoplastic resin, treatment efficacy and follow-up are insufficient to provide definitive conclusions at this time. Therefore, this position paper should be revised based on future studies and a clinical guideline should be provided. PMID:24746524

  19. [Esthetic and technical aspects of conventional removable dentures. Design of a complete denture in the upper jaw and a telescopic denture in the lower jaw. A case report].

    PubMed

    Teubner, Eckart; Lorenzon, Andreas; Marinello, Carlo P

    2007-01-01

    Removable partial dentures and complete dentures are still an important part of the daily prosthetic work of dentists and dental technicians. Thereby the esthetic design of conventional fixed restorations is challenging the dentist and the dental technician in removable prosthodontics. The result is mainly influenced by the clinical and technical procedure as well as by the choice of material. In this article, the reconstruction of a patient with a complete removable dental prosthesis in the upper jaw and an overlay denture on four telescopes in the lower jaw is presented. PMID:17557643

  20. 21 CFR 872.3600 - Partially fabricated denture kit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Identification. A partially fabricated denture kit is a device composed of connected preformed teeth that is... with the oral tissues. After the denture base is constructed, the connected preformed teeth...

  1. 21 CFR 872.3600 - Partially fabricated denture kit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Identification. A partially fabricated denture kit is a device composed of connected preformed teeth that is... with the oral tissues. After the denture base is constructed, the connected preformed teeth...

  2. 21 CFR 872.3600 - Partially fabricated denture kit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Identification. A partially fabricated denture kit is a device composed of connected preformed teeth that is... with the oral tissues. After the denture base is constructed, the connected preformed teeth...

  3. 21 CFR 872.3600 - Partially fabricated denture kit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Identification. A partially fabricated denture kit is a device composed of connected preformed teeth that is... with the oral tissues. After the denture base is constructed, the connected preformed teeth...

  4. 21 CFR 872.3600 - Partially fabricated denture kit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) Identification. A partially fabricated denture kit is a device composed of connected preformed teeth that is... with the oral tissues. After the denture base is constructed, the connected preformed teeth...

  5. Zirconia-based dental crown to support a removable partial denture: a three-dimensional finite element analysis using contact elements and micro-CT data.

    PubMed

    Rocha, Eduardo Passos; Anchieta, Rodolfo Bruniera; de Almeida, Erika Oliveira; Freitas, Amilcar Chagas; Martini, Ana Paula; Sotto-Maior, Bruno Sales; Luersen, Marco Antonio; Ko, Ching Chang

    2015-01-01

    Veneer fracture is the most common complication in zirconia-based restorations. The aim of this study was to evaluate the mechanical behavior of a zirconia-based crown in a lower canine tooth supporting removable partial denture (RPD) prosthesis, varying the bond quality of the veneer/coping interface. Microtomography (μCT) data of an extracted left lower canine were used to build the finite element model (M) varying the core material (gold core - MAu; zirconia core - MZi) and the quality of the veneer/core interface (complete bonded - MZi; incomplete bonded - MZi-NL). The incomplete bonding condition was only applied for zirconia coping by using contact elements (Target/Contact) with 0.3 frictional coefficients. Stress fields were obtained using Ansys Workbench 10.0. The loading condition (L = 1 N) was vertically applied at the base of the RPD prosthesis metallic support towards the dental apex. Maximum principal (σmax) and von Mises equivalent (σvM) stresses were obtained. The σmax (MPa) for the bonded condition was similar between gold and zirconia cores (MAu, 0.42; MZi, 0.40). The incomplete bonded condition (MZi-NL) raised σmax in the veneer up to 800% (3.23 MPa) in contrast to the bonded condition. The peak of σvM increased up to 270% in the MZi-NL. The incomplete bond condition increasing the stress in the veneer/zirconia interface. PMID:25331825

  6. The role of friction in the mechanism of retaining the partial removable dentures with double crown system.

    PubMed

    Dąbrowa, Tomasz; Dobrowolska, Anna; Wieleba, Wojciech

    2013-01-01

    Cylindrical telescopic crowns belong to bolt dentures, because their adhesion strength is based on the friction force. The magnitude of static and slide friction forces depends on the strain within the contact area and properties of materials employed. Friction force value between telescope elements declines in the first phase of wearing period and, subsequently, maintains particular constant value of 8 to 10 N. In the telescopic technique, homo and heterogenic joints are used. The following prosthodontic materials have been examined: goldbase alloys (Degudent Kiss, Degulor M), cobalt-base alloy (Brealloy 270), ceramics (Zircon Oxide, Zirconia) during tribological investigations on FGP composite resin. The cooperating surfaces were moistened with synthetic saliva. The research confirmed the dependence of the static friction coefficient on the contact pressure for the analyzed pairs of materials used in prosthodontics. The biggest effect of the contact pressure on the coefficient of friction value occurs when the ceramic rubs on FGP composite resin. The most stable friction coefficient in the context of contact pressure changes as well as life has been found in the case of the cobalt alloy Brealloy 270. An interesting material is a gold alloy Degulor M, for which the coefficient of friction varies only slightly with pressure in the range of 0.6 to 0.9 MPa. PMID:24479667

  7. Effects of Length and Inclination of Implants on Terminal Abutment Teeth and Implants in Mandibular CL1 Removable Partial Denture Assessed by Three-Dimensional Finite Element Analysis

    PubMed Central

    Fayaz, Amir; Geramy, Alahyar; Memari, Yeganeh

    2015-01-01

    Objectives: This study sought to assess the effects of length and inclination of implants on stress distribution in an implant and terminal abutment teeth in an implant assisted-removable partial denture (RPD) using three-dimensional (3D) finite element analysis (FEA). Materials and Methods: In this in vitro study, a 3D finite element model of a partially dentate mandible with a distal extension RPD (DERPD) and dental implants was designed to analyze stress distribution in bone around terminal abutment teeth (first premolar) and implants with different lengths (7 and 10 mm) and angles (0°, 10° and 15°). Results: Stress in the periodontal ligament (PDL) of the first premolar teeth ranged between 0.133 MPa in 10mm implants with 15° angle and 0.248 MPa in 7mm implants with 0° angle. The minimum stress was noted in implants with 10mm length with 0° angle (19.33 MPa) while maximum stress (25.78 MPa) was found in implants with 10mm length and 15° angle. In implants with 7 mm length, with an increase in implant angle, the stress on implants gradually increased. In implants with 10 mm length, increasing the implant angle gradually increased the stress on implants. Conclusion: Not only the length of implant but also the angle of implantation are important to minimize stress on implants. The results showed that vertical implant placement results in lower stress on implants and by increasing the angle, distribution of stress gradually increases.

  8. Ingestion of a Fixed Partial Denture During General Anesthesia

    PubMed Central

    Neustein, Steve; Beicke, Mark

    2007-01-01

    Dental trauma during anesthesia is a common occurrence. Many patients have had extensive dental work, which is more fragile than the natural dentition. This work may include crowns, fixed partial dentures (bridges), and porcelain veneers. We report for the first time, a case in which a fixed partial denture became dislodged and was ingested, and was recovered postoperatively with endoscopy. PMID:17579503

  9. The cantilever fixed partial denture--a literature review.

    PubMed

    Himmel, R; Pilo, R; Assif, D; Aviv, I

    1992-04-01

    The cantilever fixed partial denture (FPD) is a restoration with one or more abutments at one end and unsupported at the other end. Forces transmitted through the cantilevered pontics can cause tilting and rotational movements of the abutments. In a cross-arch unilateral cantilever FPD, the distal cantilevered unit is subjected to comparatively less force than the contralateral posterior abutment. The unilateral lack of terminal abutments causes lateral bending forces activate peripheral inhibitory feedback reactions from the periodontal and/or temporomandibular mechanoreceptors. The greatest strain in distal cantilevered FPDs is recorded mesial to the most distal retainer because most fractures occur in this location. To improve the prognosis of the FPD cantilever, the number of abutments should be increased and the number of pontics decreased. The abutment teeth need long roots and acceptable alveolar support. Prepared abutments require adequate length and parallel axial walls. An equilibrated and harmonious occlusion is necessary, as well as exemplary oral hygiene. A cantilevered FPD with adequate periodontal support can replace any tooth in the dental arch, but is especially useful as an alternative to a removable partial denture. The cantilevered FPD requires at least two abutment teeth. The only documented exception permitting a single abutment is the replacement of a maxillary lateral incisor with the canine as an abutment. An alternative to the cantilevered FPD is the osseointegrated implant. As osseointegrated implants become more popular, the need for the tooth-supported cantilevered FPD may decline, but it will remain an alternative treatment modality. PMID:1507130

  10. Risk management in clinical practice. Part 6b. Identifying and avoiding medico-legal risks in removable dentures.

    PubMed

    Stilwell, C

    2010-10-01

    The most likely cause of complaint with prosthodontics is a denture that in some way fails to be accepted. A denture that does not perform as the patient expects can give rise to great disappointment and anger. The problem is that acceptance of a denture is not just a technical issue. Success depends on the individual's ability to tolerate and adapt to the denture. It is therefore essential to make the right assessment for the patient from the outset. This includes discovering the patient's priorities and establishing realistic expectations. With the aim of assisting the dental profession in identifying and avoiding medico-legal risks in removable dentures, this article sets out a systematic, diagnostic and collaborative approach to complete and partial denture assessment and treatment. PMID:20930774

  11. The effectiveness of chemical denture cleansers and ultrasonic device in biofilm removal from complete dentures

    PubMed Central

    CRUZ, Patrícia Costa; de ANDRADE, Ingrid Machado; PERACINI, Amanda; de SOUZA-GUGELMIN, Maria Cristina Monteiro; SILVA-LOVATO, Cláudia Helena; de SOUZA, Raphael Freitas; PARANHOS, Helena de Freitas Oliveira

    2011-01-01

    Adequate denture hygiene can prevent and treat infection in edentulous patients. They are usually elderly and have difficulty for brushing their teeth. Objective This study evaluated the efficacy of complete denture biofilm removal using chemical (alkaline peroxide-effervescent tablets), mechanical (ultrasonic) and combined (association of the effervescent and ultrasonic) methods. Material and Methods Eighty complete denture wearers participated in the experiment for 21 days. They were distributed into 4 groups (n=20): (1) Brushing with water (Control); (2) Effervescent tablets (Corega Tabs); (3) Ultrasonic device (Ultrasonic Cleaner, model 2840 D); (4) Association of effervescent tablets and ultrasonic device. All groups brushed their dentures with a specific brush (Bitufo) and water, 3 times a day, before applying their treatments. Denture biofilm was collected at baseline and after 21 days. To quantify the biofilm, the internal surfaces of the maxillary complete dentures were stained and photographed at 45º. The photographs were processed and the areas (total internal surface stained with biofilm) quantified (Image Tool 2.02). The percentage of the biofilm was calculated by the ratio between the biofilm area multiplied by 100 and the total area of the internal surface of the maxillary complete denture. Results The Kruskal-Wallis test was used for comparison among groups followed by the Dunn multiple-comparison test. All tests were performed respecting a significance level of 0.05. Significant difference was found among the treatments (KW=21.18; P<0.001), the mean ranks for the treatments and results for Dunn multiple comparison test were: Control (60.9); Chemical (37.2); Mechanical (35.2) and Combined (29.1). Conclusion The experimental methods were equally effective regarding the ability to remove biofilm and were superior to the control method (brushing with water). Immersion in alkaline peroxide and ultrasonic vibration can be used as auxiliary agents for

  12. Biomechanical considerations on tooth-implant supported fixed partial dentures

    PubMed Central

    Calvani, Pasquale; Hirayama, Hiroshi

    2012-01-01

    This article discusses the connection of teeth to implants, in order to restore partial edentulism. The main problem arising from this connection is tooth intrusion, which can occur in up to 7.3% of the cases. The justification of this complication is being attempted through the perspective of biomechanics of the involved anatomical structures, that is, the periodontal ligament and the bone, as well as that of the teeth- and implant-supported fixed partial dentures. PMID:23255882

  13. A review of computer-aided design/computer-aided manufacture techniques for removable denture fabrication

    PubMed Central

    Bilgin, Mehmet Selim; Baytaroğlu, Ebru Nur; Erdem, Ali; Dilber, Erhan

    2016-01-01

    The aim of this review was to investigate usage of computer-aided design/computer-aided manufacture (CAD/CAM) such as milling and rapid prototyping (RP) technologies for removable denture fabrication. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect, Google Scholar, and Web of Science databases. Databases were searched from 1987 to 2014. The search was performed using a variety of keywords including CAD/CAM, complete/partial dentures, RP, rapid manufacturing, digitally designed, milled, computerized, and machined. The identified developments (in chronological order), techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication are summarized. Using a variety of keywords and aiming to find the topic, 78 publications were initially searched. For the main topic, the abstract of these 78 articles were scanned, and 52 publications were selected for reading in detail. Full-text of these articles was gained and searched in detail. Totally, 40 articles that discussed the techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication and the articles were incorporated in this review. Totally, 16 of the papers summarized in the table. Following review of all relevant publications, it can be concluded that current innovations and technological developments of CAD/CAM and RP allow the digitally planning and manufacturing of removable dentures from start to finish. As a result according to the literature review CAD/CAM techniques and supportive maxillomandibular relationship transfer devices are growing fast. In the close future, fabricating removable dentures will become medical informatics instead of needing a technical staff and procedures. However the methods have several limitations for now. PMID:27095912

  14. A review of computer-aided design/computer-aided manufacture techniques for removable denture fabrication.

    PubMed

    Bilgin, Mehmet Selim; Baytaroğlu, Ebru Nur; Erdem, Ali; Dilber, Erhan

    2016-01-01

    The aim of this review was to investigate usage of computer-aided design/computer-aided manufacture (CAD/CAM) such as milling and rapid prototyping (RP) technologies for removable denture fabrication. An electronic search was conducted in the PubMed/MEDLINE, ScienceDirect, Google Scholar, and Web of Science databases. Databases were searched from 1987 to 2014. The search was performed using a variety of keywords including CAD/CAM, complete/partial dentures, RP, rapid manufacturing, digitally designed, milled, computerized, and machined. The identified developments (in chronological order), techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication are summarized. Using a variety of keywords and aiming to find the topic, 78 publications were initially searched. For the main topic, the abstract of these 78 articles were scanned, and 52 publications were selected for reading in detail. Full-text of these articles was gained and searched in detail. Totally, 40 articles that discussed the techniques, advantages, and disadvantages of CAD/CAM and RP for removable denture fabrication and the articles were incorporated in this review. Totally, 16 of the papers summarized in the table. Following review of all relevant publications, it can be concluded that current innovations and technological developments of CAD/CAM and RP allow the digitally planning and manufacturing of removable dentures from start to finish. As a result according to the literature review CAD/CAM techniques and supportive maxillomandibular relationship transfer devices are growing fast. In the close future, fabricating removable dentures will become medical informatics instead of needing a technical staff and procedures. However the methods have several limitations for now. PMID:27095912

  15. Avoiding osseous grafting in the atrophic posterior mandible for implant-supported fixed partial dentures: a report of 2 cases.

    PubMed

    Flanagan, Dennis

    2011-12-01

    Bone atrophy occurs after tooth extraction in the posterior mandible, placing the mandibular canal and its neural, arterial, and venous contents closer to the osseous facial aspect and the coronal crest. This proximity places the structure in danger of damage when dental implants are surgically placed to support fixed or removable prostheses. Several options are available to treat these areas for implant-supported fixed and removable complete or partial dentures. Osseous grafting and ridge expansion are surgical options that enable acceptance of standard sized dental implants but have serious morbidities. Additionally, vertical osseous augmentation is not predictable at this time. Narrow diameter dental implants can be placed to avoid the mandibular canal, but some bone volume situations preclude this. Very wide and very short (6.5 × 5 mm) dental implants may be placed at an angle in atrophic sites to successfully support fixed partial dentures. An anterior guidance occlusal scheme may be used in maxillary dentate patients or group function in maxillary complete denture patients. A 100 micron occlusal relief in fixed partial dentures in dentate patients may be required to account for natural tooth intrusion and to prevent occlusal overload of the implant-supported partial denture. PMID:20925498

  16. Dentures

    MedlinePlus

    ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ... Dental Implants Dentures Direct Bonding Implants versus Bridges Orthodontics and Aligners Periodontal Plastic Surgery Porcelain Crowns Porcelain ...

  17. Partial denture metal framework may harbor potentially pathogenic bacteria

    PubMed Central

    Bernardes, Luciano Angelo de Souza; Gomes, Sabrina Carvalho; Silva, Alecsandro Moura

    2015-01-01

    PURPOSE The aim of this study was to characterize and compare bacterial diversity on the removable partial denture (RPD) framework over time. MATERIALS AND METHODS This descriptive pilot study included five women who were rehabilitated with free-end mandibular RPD. The biofilm on T-bar clasps were collected 1 week (t1) and 4 months (t2) after the RPD was inserted (t0). Bacterial 16S rDNA was extracted and PCR amplified. Amplicons were cloned; clones were submitted to cycle sequencing, and sequences were compared with GenBank (98% similarity). RESULTS A total of 180 sequences with more than 499 bp were obtained. Two phylogenetic trees with 84 (t1) and 96 (t2) clones represented the bacteria biofilm at the RPD. About 93% of the obtained phylotypes fell into 25 known species for t1 and 17 for t2, which were grouped in 5 phyla: Firmicutes (t1=82%; t2=60%), Actinobacteria (t1=5%; t2=10%), Bacteroidetes (t1=2%; t2=6%), Proteobacteria (t1=10%; t2=15%) and Fusobacteria (t1=1%; t2=8%). The libraries also include 3 novel phylotypes for t1 and 11 for t2. Library t2 differs from t1 (P=.004); t1 is a subset of the t2 (P=.052). Periodontal pathogens, such as F. nucleatum, were more prevalent in t2. CONCLUSION The biofilm composition of the RPD metal clasps changed along time after RPD wearing. The RPD framework may act as a reservoir for potentially pathogenic bacteria and the RPD wearers may benefit from regular follow-up visits and strategies on prosthesis-related oral health instructions. PMID:26816577

  18. Telescopic Overdenture and Implant Supported Fixed Partial Denture: A Pragmatic Treatment Approach

    PubMed Central

    Dede, Doğu Ömür; Cenk Durmuşlar, M.; Şahın, Onur; Köroğlu, Ayşegül; İşısağ, Özer

    2015-01-01

    This case report presents a patient who had been rehabilitated with a telescopic overdenture and implant supported fixed partial denture (ISFPD). The treatment process was as follows: (1) fabricating telescopic crowns and overdenture prosthesis for the lower jaw and a temporary complete denture for the upper jaw, (2) using the temporary denture as diagnostic and surgical guide to optimize dental implant placement, and (3) fabricating ISFPD for the upper jaw. Using the patient's existing or temporary denture not only serves as an alternative surgical guide to calibrate the dental implant locations but also helps to finish the restoration at desired dimension, size, and anatomic form. PMID:26106491

  19. Fiber-reinforced composites in fixed partial dentures

    PubMed Central

    Vallittu, Pekka

    2006-01-01

    Fiber-reinforced composite resin (FRC) prostheses offer the advantages of good aesthetics, minimal invasive treatment, and an ability to bond to the abutment teeth, thereby compensating for less-than-optimal abutment tooth retention and resistance form. These prostheses are composed of two types of composite materials: fiber composites to build the framework and hybrid or microfill particulate composites to create the external veneer surface. This review concentrates on the use of fiber reinforcement in the fabrication of laboratory or chairsidemade composite-fixed partial dentures of conventional preparation. Other applications of FRC in dentistry are briefly mentioned. The possibilities fiber reinforcement technology offers must be emphasized to the dental community. Rather than limiting discussion to whether FRC prostheses will replace metal-ceramic or full-ceramic prostheses, attention should be focused on the additional treatment options brought by the use of fibers. However, more clinical experience is needed. PMID:21526023

  20. Fixed partial dentures investigated by optical coherent tomography

    NASA Astrophysics Data System (ADS)

    Sinescu, Cosmin; Negrutiu, Meda; Todea, Carmen; Hughes, Mike; Tudorache, Florin; Podoleanu, Adrian G.

    2008-02-01

    Fixed partial prostheses as integral ceramics, integral polymers, metal ceramics or metal polymers bridges, are mainly used in the frontal part of the dental arch (especially the integral bridges). They have to satisfy high stress requirements as well as esthetic. The masticatory stress may induce fractures of the bridges. These may be triggered by initial materials defects or by alterations of the technological process. The fractures of these bridges lead to functional, esthetic and phonetic disturbances which finally render the prosthetic treatment inefficient. The purpose of this study is to evaluate the capability of en-face optical coherence tomography (OCT) in detection and analysis of possible fractures in several integral fixed partial dentures. The materials used were represented by several fixed partial prostheses, integral ceramics, integral polymers, metal ceramics and metal polymers bridges. In order to discover the defects, scanning was performed from incisal, vestibular, oral and cervical directions material defects such as fractures and pores were investigated using OCT. In conclusion, en-face OCT has proven as a valuable non invasive method to investigate fixed partial prostheses before their insertion in the oral cavity.

  1. Direct and indirect fiber-reinforced fixed partial dentures: case reports.

    PubMed

    Ahlstrand, Wisua M; Finger, Werner J

    2002-05-01

    Direct and indirect fiber-reinforced resin composite fixed partial dentures are a new way to produce minimally invasive, esthetic, and cost-effective metal-free tooth replacements. These treatment alternatives have a number of indications, for example, chairside tooth replacements, long-term provisional fixed partial dentures, economically feasible tooth replacements for patients who cannot afford more traditional treatment regimens, and tooth replacements for medically compromised patients who are unable to withstand the physical stress associated with fabrication of traditional fixed prostheses. This article presents four typical cases in which fiber-reinforced fixed partial dentures seemed to be the preferable treatment modality. PMID:12014165

  2. Intraoral repair of all ceramic fixed partial denture utilizing preimpregnated fiber reinforced composite.

    PubMed

    Turkaslan, Süha; Tezvergil-Mutluay, Arzu

    2008-01-01

    All ceramic fixed partial dentures (FPD)s exhibit enhanced biocompatibility and esthetics as compared to metal-ceramic restorations. However, framework fractures are frequently reported especially when the connector dimensions are inadequate to withstand the high tensile stresses. The repair of the failed connector would be desirable rather than the complete removal and renewal since the latter is an expensive and time consuming procedure. Furthermore, the replacement or removal of the restoration for extra-oral repair purposes might increase the risk of destroying the entire restoration or damaging the abutment teeth during the removal. This article presents a direct intra-oral method that may be used to repair the connector fractures of all-ceramic FPDs which are otherwise clinically satisfactory. In the present technique, the connector is reconstructed intraorally utilizing composite resin restorative material reinforced with E-glass-fiber. PMID:19212511

  3. A study of dentists’ preferences for the restoration of shortened dental arches with partial dentures

    PubMed Central

    Nassani, Mohammad Zakaria; Ibraheem, Shukran; Al-Hallak, Khaled Rateb; Ali El Khalifa, Mohammed Othman; Baroudi, Kusai

    2015-01-01

    Objective: This study aimed to use a utility method in order to assess dentists’ preferences for the restoration of shortened dental arches (SDAs) with partial dentures. Also, the impact of patient age and length of the SDA on dentists’ preferences for the partial dentures was investigated. Materials and Methods: Totally, 104 subjects holding a basic degree in dentistry and working as staff members in a private dental college in Saudi Arabia were interviewed and presented with 12 scenarios for patients of different ages and mandibular SDAs of varying length. Participants were asked to indicate on a standardized visual analog scale how they would value the health of the patient's mouth if the mandibular SDAs were restored with cobalt-chromium removable partial dentures (RPDs). Results: With a utility value of 0.0 representing the worst possible health state for a mouth and 1.0 representing the best, dentists’ average utility value of the RPD for the SDAs was 0.49 (sd= 0.15). Mean utility scores of the RPDs across the 12 SDA scenarios ranged between 0.35 and 0.61. RPDs that restored the extremely SDAs attracted the highest utility values and dentists’ utility of the RPD significantly increased with the increase in the number of missing posterior teeth. No significant differences in dentists’ mean utility values for the RPD were identified among SDA scenarios for patients of different ages. Conclusion: Restoration of the mandibular SDAs by RPDs is not a highly preferred treatment option among the surveyed group of dentists. Length of the SDA affects dentists’ preferences for the RPD, but patient age does not. PMID:26038647

  4. Development of a device to study fatigue life of fixed partial dentures

    NASA Astrophysics Data System (ADS)

    Gutierrez, S. C.; Meseguer, M. D.; Estal, R.; Folguera, F.; Vidal, V.

    2012-04-01

    Fixed partial dentures can be fabricated by means of different materials and with different manufacturing processes. In order to establish possible differences among them, their behaviour, as fatigue life or cement shear bond strength, have to be evaluated. This article presents a modular, economic and robust device to evaluate fixed partial dentures and dental crowns. A base to support the fixed partial dentures and a device to simulate masticatory loads have been developed. The device has got a simple design. It is based on a pneumatic piston, with a pressure regulator to control masticatory loads. On a first stage, only vertical forces have been taking into account. However, the device will allow simulating tangential masticatory loads on the other axis, studying the behaviour of the fixed partial dentures submerged in a solution similar to saliva, changing masticatory load application, etc. with little modifications.

  5. Single implant and crown versus fixed partial denture: A cost-benefit, patient-centred analysis.

    PubMed

    Goodacre, Charles J; Naylor, W Patrick

    2016-01-01

    Single implants and their crowns have high survival rates that exceed the survival rates for fixed partial dentures on teeth and most but not all publications have determined single implants are more cost-effective than 3-unit fixed partial dentures. Both initial root canal treatment and retreatment are more cost-effective than tooth extraction and rehabilitation with a single implant and crown. PMID:27314112

  6. Improved design of long-span resin-bonded fixed partial dentures: three case reports.

    PubMed

    Botelho, Michael G

    2003-03-01

    When single-tooth implants are not appropriate, the use of resin-bonded fixed partial dentures is a preferred treatment option when the abutments are relatively sound. However, the use of resin-bonded fixed partial dentures (RBFPDs) for replacing two or more missing teeth is considered to have a guarded prognosis, as long-span RBFPDs have been shown to be less successful than single pontic prostheses. The use of properly modified nonrigid connectors may well improve the success of long-span RBFPDs by reducing harmful interabutment stresses that appear to be responsible for retainer debonding in long-span RBFPDs. For such long-span prostheses, it is advised that the major retainer have wraparound on at least three surfaces of the abutment or have strategically placed opposing axial grooves or slots. It is considered essential that the connector allow interabutment movement in both the horizontal and vertical planes so that the retainer with the greater resistance and retention form does not stress and possibly debond the minor retainer. The upside-down positioning of the nonrigid connector and the matrix incorporated with the major retainer is considered important for successful maintenance, if a debond should occur due to greater loading on the major retainer, because it can be removed and recemented easily. Clinical cases are described that replace two or more missing teeth using fixed-movable RBFPDs with nonrigid connectors. PMID:12731596

  7. Strength of zirconia fixed partial dentures: review of the literature

    PubMed Central

    GARGARI, M.; GLORIA, F.; CAPPELLO, A.; OTTRIA, L.

    2011-01-01

    SUMMARY Objective The aim of this study is a systematic review of the literature on the strength and long-term behavior of zirconia FPDs. Methods The literature search was performed using as the primary source the Medline database. Were also imposed a set of inclusion and exclusion criteria in order to narrow the search to differentiate the two distinct parts in which it was structured the review. In addition, MeSH terms were applied to further refine the choice of articles more relevant to the review. In the part of the review concerning the long-term behavior of zirconia fixed partial dentures were considered useful only those studies with a minimum follow-up of one year. Results The search provided a total of 813 articles, but only 25 were considered for the review because they were the only ones who satisfied search criteria. In particular, 13 items relate to the mechanical strength of zirconia prostheses and 12 regarding the long term behavior of zirconia FPDs. The resistance values also exceed the 2000 N while the survival rate reaches to almost 94%. Conclusions Based on this review, Zirconia FPDs can be considered reliable products in both the anterior and posterior fields with survival rates comparable to traditional metal-ceramic prostheses. PMID:23285392

  8. Bonding a veneered zirconia anterior fixed partial denture.

    PubMed

    Lawson, Nathaniel C; Chavali, Ramakiran; Burgess, John O

    2015-01-01

    This case report documents the rationale and procedure for bonding a veneered zirconia restoration. A three-unit zirconia fixed partial denture (FPD) was fabricated with facial and incisal porcelain veneering. The intaglio surface of the prosthesis was abraded with 50-μm aluminum oxide (Al2O3) particles and coated with one layer of a 10-methacryloxydecyl dihydrogen phosphate (MDP) primer. The FPD was tried into the mouth and occlusal adjustment was performed with a fine grit diamond, and then it was polished with zirconia polishing points. The intaglio surfaces of the abutment crowns were cleaned with 37% phosphoric acid and rinsed. A self-etch adhesive was applied to the tooth preparations and light-cured, and the crowns were filled with cement and seated. Excess cement was immediately wiped away with a brush, followed by spot-curing of the margins. The case demonstrates that, when properly designed, veneered zirconia restorations offer acceptable esthetic and mechanical properties for anterior FPDs. PMID:25822406

  9. Fabrication of a multi-applicable removable intraoral denture system for rodent research

    PubMed Central

    Lee, Heeje; Yu, Alika; Johnson, Clorinda C.; Noverr, Mairi C.; Fidel, Paul L.

    2011-01-01

    SUMMARY The objective was to engineer an inexpensive intraoral removable denture system for rodents that can be utilized in numerous oral health research applications. At the forefront is biofilm research related to Candida-associated denture stomatitis. Previously described intraoral devices are primitive and inadequate. The denture system was engineered consisting of a fixed part that is anchored to the posterior palate by orthodontic wires and acrylic resin, and a removable part fitted to the anterior palate that is retained by magnets embedded in the fixed part. Both parts are custom-fitted to the rodent palate by impression making and cast fabrication. Rats fitted with the intraoral denture system maintained body weight and normal activity with the device maintaining integrity and durability for upwards of 8 weeks. The denture system was used successfully to establish a working model of denture stomatitis. This newly engineered inexpensive intraoral removable denture system for rodents can be utilized in numerous oral health research applications, including denture-associated infections, biofilms, and a variety of biomaterial applications. The removable portion is advantageous for longitudinal analyses and charging/discharging of biomaterials. PMID:21323935

  10. Marginal Integrity of CAD/CAM Fixed Partial Dentures

    PubMed Central

    Rosentritt, Martin; Behr, Michael; Kolbeck, Carola; Handel, Gerhard

    2007-01-01

    Objectives Computer-aided design (CAD) and manufacturing (CAM) allows the milling of high strength zirconia fixed partial dentures (FPD), however bonding to an inert ZrO2 ceramic surface may effect the marginal integrity of the FPDs. The aim of this investigation was to evaluate the marginal adaptation of zirconia FPDs at the interfaces between zirconia, cement, and tooth. Methods 32 3-unit FPDs were fabricated of the CAD/CAM Y-TZP zirconia (Lava, 3M Espe, Germany) according to the manufacturers’ instructions. Resin cements with corresponding primer and bonding systems were used to lute the FPDs: Compolute/EBS multi (3M Espe, Germany), Panavia F/ED (Kuraray, Japan), Variolink 2/Syntac classic (Ivoclar-Vivadent, FL) and RelyX Unicem/without treatment (3M Espe, Germany). Aualloy FPDs (BioPontostar, Bego, Germany) were cemented with RelyX Unicem and Harvard (Harvard, Germany) as the control. Marginal adaptation was evaluated with scanning electron microscopy using replica specimen before and after artificial aging. After aging, microleakage tests were performed with fuchsine solution. The interfaces between cement-tooth and cement-FPD were examined. Results At the interfaces (cement-tooth and cement-FPD), the systems showed a 95% or higher perfect margin before and after aging. Only Variolink2/Syntac had a marginal adaptation, lower than a 70% perfect margin. Generally, the fuchsine penetration was below 20%, only BioPontstar/Harvard andLava/Variolink2 showed penetration results between 80% and 100%. Conclusion The success of the adhesive cementation of zirconia FPDs depends on the cement system. Under the conditions of this study, zirconia FPDs showed good to sufficient marginal integrity in combination with Panavia/ED, Compolute/EBS and RelyX Unicem. PMID:19212494

  11. Frequency and location of artificial crowns and fixed partial dentures constructed at a dental school.

    PubMed

    Valderhaug, J; Karlsen, K

    1976-01-01

    The material consists of patients who received single crowns and fixed partial dentures at the Department of Prosthetics, Dental Faculty, University of Oslo in the period 1967-73. Two-thirds of the patients were women, and about two-thirds of the restorations were made in the maxilla. A total of 3275 crowns were received by 2145 patients. On average, maxillary teeth were crowned 7 years earlier than mandibular teeth. A total of 1393 fixed partial dentures, consisting of 6835 units, were made for 1368 patients. PMID:1063259

  12. [Evaluation of cermet fillings in abutment teeth in removable partial prostheses].

    PubMed

    Saulic, S; Tihacek-Sojic, Lj

    2001-01-01

    The aim of the study was to describe the clinical process of setting the purpose filling on abutment teeth, after finishing the removable partial dentures. The aim was also to investigate the use of cermet glass-ionomer cement for the purpose filling in the abutment teeth for removable partial dentures, as well as to investigate the surface of the purpose filling. For the clinical evaluation of purpose filling slightly modified criteria according to Ryg's were used in 20 patients with different type of edentulousness. Changes occurring on the surface of purpose filling have been experimentally established by the method of scanning electron microscopy on the half-grown third molars in seven patients. It could be concluded that cement glass-ionomer was not the appropriate material for the purpose fillings in abutment teeth for removable partial dentures. PMID:11858021

  13. Rehabilitation of oral function with removable dentures--still an option?

    PubMed

    Xie, Q; Ding, T; Yang, G

    2015-03-01

    Tooth loss is a chronic disability, which makes it difficult for patients to perform essential tasks such as eating, communicating with others and socialising. Numerous studies have revealed and addressed the recent rapid development of various prosthodontic materials and treatment patterns. Oral rehabilitation with dentures exerts a great influence on people's daily life and has tremendous social implications. Dentures help to restore an individual's sense of normality and ability to interact normally. With the introduction and progression of implant technology, many troublesome issues can now be solved simply. Nowadays, more and more attention has been paid to new trends (implant-assisted restoration and fixed prostheses). However, removable dentures may be a more appropriate solution under some circumstances, such as if they are a patient's preferred option, if remaining oral tissues are in poor condition, or if they provide the most cost-effective form of treatment. Thus, removable dentures are still an option for the rehabilitation of oral function. The purpose of this article was to retrospectively review the applications of removable dentures and to emphasise their indispensable status. PMID:25327636

  14. Mini Implants Supporting Fixed Partial Dentures in the Posterior Mandible: A Retrospective.

    PubMed

    Flanagan, Dennis

    2015-08-01

    Small-diameter, or mini, dental implants have been successfully used to support removable and fixed oral prostheses. These implants impart about twice the per-square-millimeter force on the supporting bone and this should be addressed during treatment planning. In the posterior jaws, bite forces are of a higher magnitude than in the anterior jaws and may induce an overload of the supporting bone and failure of the osseointegration. Thus there should not be occlusal contact in functional excursions that induce off axial loads. The cases presented herein demonstrate that mini dental implants may be used successfully to support fixed partial dentures in mandibular sites in highly selected patients. Attention should be given to the bone density of the site, very slow seating rotation of the implant with intermissions or cooling during insertion, observation of a 4-month healing time, flapless placement, treatment of any existing periodontitis, an insoluble cement, and exclusion of occlusal contact in functional excursions. Importantly, a narrow, rounded occlusal table should be used to minimize off axial loads and an insoluble luting cement should be used to prevent loosening of the crowns due to dissolution of the cement and an overload of the retained implant with any residual cement-retained in the retainer. The implant that supports the cement retained retainer will be subjected to leveraged rotation that may destroy the osseointegration and result in exfoliation of the implant. PMID:24779887

  15. Glass-infiltrated zirconia/alumina-based ceramic for crowns and fixed partial dentures.

    PubMed

    McLaren, E A; White, S N

    1999-10-01

    The increased demand for metal-free restorative alternatives has resulted in the proliferation of all-ceramic systems. While these materials can predictably achieve aesthetic results in the anterior, they have traditionally been contraindicated for posterior applications due to the greater stresses present in the region. This article discusses a zirconia/alumina-based ceramic system that has been developed to expand the alternatives for the aesthetic restoration of the dentition. Material properties and considerations for its use in crown restorations, fixed partial dentures, and custom implant abutments are similarly addressed. PMID:10853604

  16. Microspectral analysis with laser in microleakage evaluation between infrastructure and veneer materials in fixed partial dentures

    NASA Astrophysics Data System (ADS)

    Negrutiu, Meda L.; Sinescu, Cosmin; Draganescu, Gheorghe; Todea, Carmen; Dodenciu, Dorin; Rominu, Roxana

    2008-02-01

    The microleakage at the interface between the metal infrastructure and the veneering part of the fixed partial dentures are a common problem of aesthetic dentistry. It is possible to use the method of laser microspectral analysis for investigations of microleakage at the metal-veneering material interfaces in fixed partial prostheses. The laser microspectral analysis device LMA-10 (Carl Zeiss, Jena) was used equipped with a diffraction spectrometer PGS-2 (Carl Zeiss, Jena). Different fixed partial dentures were used to determine the microleakage between the metal infrastructure and the veneering material. The distribution of chemical elements at interface infiltration was investigated, making a series of craters and establishing the spectra of the vapours emitted from the craters. Data was gathered in various tables of chemical elements showing the quality and the quantity of microleakage. The laser microspectral analysis is a punctual method of analysis, which allows to investigate small quantities of materials of around 0.1 μg. This method allows to establish the content of atoms and molecules and to perform semi-quantitative and quantitative analysis. By this method it is possible to establish trace elements, i. e. with concentration of ppm (parts per million).

  17. Emergency direct fabrication of a resin fixed partial denture by using a ceramometal crown with reinforcing woven polyethylene ribbon as a pontic.

    PubMed

    Miller, T E; Rudo, D N

    1995-01-01

    In this emergency case of a fractured tooth, immediate short-term treatment was necessary to relieve pain and replace a missing coronal portion of the maxillary central incisor. The need to remove additional fractured root fragments subgingivally precluded accessibility to the remaining root for conventional restorative procedures. The patient could not decide which course of treatment to accept, so a fixed partial denture was fabricated, with the ceramometal crown restoration as a provisional pontic splinted to the adjacent teeth. Restoring and reinforcing the posterior composite splint with a gas plasma-treated woven polyethylene ribbon has been detailed and illustrated. This ribbon material reputed to be 10 times stronger than steel by volume, is a true reinforcing material because it is woven. Mechanically, it becomes an integral part of the splint. Because it is gas plasma-treated, the superficial layer, when placed in BIS-GMA or polymethyl methacrylate, reacts chemically with the resin. The pliable, memory-free fiber--together with the open, woven, lacelike, lock stitch leno--allows the ribbon to follow the contours of the teeth and dental arch easily. The ribbon design reduces and dissipates forces exerted onto the splinting resin. The neutral color of the material permits it to have a chameleonlike effect on the color of the resin into which it is positioned. This ribbon product has been used in other dental applications: periodontal splinting, orthodontic retention, indirect composite fixed partial dentures, long-term temporary restorations with applicability in implant treatments, repair and conversion of prostheses, and reinforcing endodontically treated teeth, and complete dentures and orthodontic retainers when weaknesses are anticipated, such as shallow palatal vaults of complete dentures against a full complement of mandibular natural teeth, and the horseshoe mandibular removable modified Hawley retainer. PMID:23087970

  18. Influence of framework design, contraction mismatch, and thermal history on porcelain checking in fixed partial dentures.

    PubMed

    Anusavice, K J; Gray, A E

    1989-01-01

    The objective of this study was to characterize the relative influence of contraction mismatch, framework design, furnace type, cooling rate, and multiple firings on immediate or delayed checking in fixed partial dentures. Frameworks for 60 anterior bridges (three-unit fixed partial dentures) were cast from a low-expansion Au-Pd alloy (O) and a high-expansion Pd-Ag alloy (J). A high-expansion porcelain (B) was applied to each of three framework designs. Firing was performed at heating rates of 56 degrees C/min and 180 degrees C/min. Specimens were cooled at two rates after each of five glazing cycles. For O-B specimens which exhibited a negative thermal contraction mismatch between 600 degrees C and 25 degrees C, 60% of the bridge specimens failed when they were subjected to slow cooling preceded by either fast or slow heating. When J-B specimens (which exhibited a smaller negative contraction mismatch) were heated and cooled rapidly, no failures occurred through all of the firing cycles. However, cracks were observed in 13.3% of the J-B bridges which were slowly heated and rapidly cooled. Delayed cracks (after the fifth glaze cycle) developed over periods of up to two years only in bridges which were slowly cooled in the furnace chamber. The results of this study suggest that checking in conventional feldspathic porcelains can be promoted by slow cooling rates and an excessive number of firing cycles. PMID:2691298

  19. Effect of framework design on fracture resistance of zirconium oxide posterior fixed partial dentures

    PubMed Central

    Salimi, Hadi; Mosharraf, Ramin; Savabi, Omid

    2012-01-01

    Introduction: The effect of framework design modifications in all-ceramic systems is not fully understood. The aim of this investigation was to evaluate the effect of different framework designs on fracture resistance of zirconium oxide posterior fixed partial dentures (FPD). Materials and Methods: Thirty two posterior zirconia FPD cores were manufactured to replace a second premolar. The specimens were divided into four groups; I: 3 × 3 connector and standard design, II: 3 × 3 connector and modified design, III: 4 × 4 connector dimension, and standard design and IV: 4 × 4 connector dimension and modified design. After storing for one week in artificial saliva and thermocycling (2000 cycles, 5-55°C), the specimens were loaded in a universal testing machine at a constant cross-head speed of 0.5 mm/min until failure occurred. The Weibull, Kruskal-Wallis, and Mann-Whitney tests were used for statistical analysis (α = 0.05). Results: The mean fracture resistance of groups with 4 × 4 mm connector was significantly higher than groups with 3 × 3 mm connector (P < 0.001). Although, the fracture resistance of the modified frameworks was increased in the present study (1.1 times), they were not significantly different from anatomic specimens (P = 0.327). Conclusions: The fracture resistance of the zirconia posterior-fixed partial dentures was significantly affected by the connector size; it was not affected by the framework modification. PMID:23559956

  20. Cu-sil dentures - a novel approach to conserve few remaining teeth: Case reports.

    PubMed

    Jain, Jayesh Kumar; Prabhu, C R Allama; Zahrane, Mohammed Al; Esawy, Mohammed Sayed Al; Ajagannanavar, Sunil Lingaraj; Pal, Kapil Singh

    2015-08-01

    The present prime concern in dentistry is on preservation of remaining natural teeth. Presence of few teeth in oral cavity help in preserving alveolar ridge integrity, maintain the proprioception, and gives psychological benefit to the patient. Transitional denture provides us with alternative treatment plan for the patients willing to replace their missing teeth while retaining their very few remaining teeth. A relatively newer type of transitional denture is Cu-sil denture. A Cu-sil denture is a denture with holes, lined by a gasket of silicone rubber, the holes thus providing space for remaining natural teeth to emerge into the oral cavity through the denture. Cu-sil denture is the simplest removable partial denture, but its fabrication requires special armamentarium and material. This case report represents a simple chairside technique to fabricate Cu-sil dentures in usual dental set-up. PMID:26464557

  1. The method of manufacture of nylon dental partially removable prosthesis using additive technologies

    NASA Astrophysics Data System (ADS)

    Kashapov, R. N.; Korobkina, A. I.; Platonov, E. V.; Saleeva, G. T.

    2014-12-01

    The article is devoted to the topic of creating new methods of dental prosthesis. The aim of this work is to investigate the possibility of using additive technology to create nylon prosthesis. As a result of experimental studies, was made a sample of nylon partially removable prosthesis using 3D printing has allowed to simplify, accelerate and reduce the coat of manufacturing high-precision nylon dentures.

  2. The qualitative assessment of cobalt-chromium castings for partial dentures.

    PubMed

    Barsby, M J; Schwarz, W D

    1989-03-25

    Criteria for objective assessment of cobalt-chromium castings have been developed. A random sample of 21 commercial dental laboratories specialising in the production of cobalt-chromium castings was selected. Identical casts and instructions for the construction of a lower partial denture framework were sent to each of them. The resultant castings were assessed according to specific criteria relating to detailed design features. Only one laboratory produced a casting which conformed completely with the design instructions. Significant defects were found in a high proportion of castings. The range of charges was from 28 pounds to 85 pounds. The results of the qualitative assessments suggest only a very weak relationship between laboratory charges and the quality of cobalt-chromium castings. Suggestions are made for minimum standards that may be applied in clinical practice. PMID:2650726

  3. Implant-connected versus tooth-connected implant-supported partial dentures: 2-year clinical and radiographic comparative evaluation.

    PubMed

    Mostafa, Tamer Mohamed; El-Sheikh, Mohamed M; Abd El-Fattah, Fadel

    2015-01-01

    The purpose of this study was to clinically and radiographically compare implant-connected and tooth-connected implant-supported fixed-detachable mandibular partial dentures. Twenty partially edentulous patients (age range: 25 to 50 years) with mandibular Kennedy Class II configurations were equally divided into two groups receiving a three-unit, fixed-detachable, screw-retained partial denture. Group 1 comprised patients with unilateral missing mandibular molars and premolars. Two implants were placed at the mandibular first premolar and first molar areas. Group 2 comprised patients with missing mandibular molars and second premolars. An implant was placed at the mandibular first molar area, the first premolar was prepared, and a coping was cemented to the tooth with permanent cement. Each case was evaluated clinically and radiographically at baseline (partial denture insertion) and after 6, 12, and 24 months. Data were collected and statistically analyzed using repeated-measures one-way and two-way analysis of variance tests. There was no statistically significant difference between the two groups (P > .05). The implant-tooth-supported prosthesis provided an equally predictable treatment option compared to the totally implant-supported prosthesis in terms of implant survival and loss of marginal bone. PMID:25909533

  4. A novel technique using arti-spot coated on fleximeter strips to determine the clearance during tooth preparation in fixed partial denture.

    PubMed

    Prasadh, Soma Sundaram

    2015-01-01

    The amount of occlusal clearance during tooth preparation for fixed partial denture is more crucial and critical phase of fixed prosthodontics. Improper tooth reduction leads to compromise in structural durability and failure of the restoration. Over reduction affects the biological principles of tooth preparation. This article uses color coded fleximeter strips coated with arti-spot to determine the amount of clearance during tooth preparation in fixed partial denture. PMID:26929480

  5. Veneering technique for a Ti-6Al-7Nb framework used in a resin-bonded fixed partial denture with a highly filled indirect composite.

    PubMed

    Matsumura, Hideo; Yoneyama, Takayuki; Shimoe, Saiji

    2002-12-01

    This article presents a veneering technique for fixed partial denture frameworks made from a Ti-6Al-7Nb alloy. The fixed partial denture framework was prepared with a magnesia-based mold material and a centrifugal casting machine. An esthetic veneer was fabricated with a highly filled dual-polymerized composite material and a metal-conditioning agent. This technique can be applied as a standardized veneering procedure for the titanium alloy, for which porcelain fusing is currently difficult. PMID:12488858

  6. Factors associated with mucosal pain in patients with partial removable dental prostheses.

    PubMed

    Kumagai, H; Fueki, K; Yoshida-Kohno, E; Wakabayashi, N

    2016-09-01

    The aim of this study was to investigate factors associated with mucosal pain in patients with partial removable dental prostheses (PRDPs). In this hospital-based cross-sectional study, 333 patients wearing 500 PRDPs (mean age 71·4 years, men 33·3%) were consecutively recruited from prosthetic clinic of a dental hospital in Japan. Subjects rated pain intensity and frequency of denture-bearing mucosa. An examiner recorded age, gender and systemic diseases as well as dental, mucosa, denture, sensory, behavioural- and psychological-related characteristics that were possibly associated with the mucosal pain. Multivariate analyses were performed to analyse factors related to mucosal pain. Pain intensity was rated as more than score 0 (presence) in 34·2% (171/500) PRDPs, and pain was experienced after denture delivery in 42·8% (214/500) PRDPs. Logistic regression analyses showed that younger age, mucosal damage, poor mucosal condition, bone prominence, poor residual ridge, higher pain sensitivity, presence of awake bruxism, perception of oral dryness, interim denture wear and high number of missing teeth were significant independent predictors for the presence of the mucosal pain intensity and/or frequency (P < 0·05). Multiple factors are associated with mucosal pain in patients with PRDPs. Oral mucosal characteristics, age, pain sensitivity and behavioural factors seem to be more critical for mucosal pain than distribution of missing teeth and number of abutment teeth. PMID:27289212

  7. Denture care practice among patients attending the prosthetic clinic in a Nigerian teaching hospital

    PubMed Central

    Ogunrinde, Tunde Joshua; Opeodu, Olanrewaju Ige

    2015-01-01

    Background: Good denture care practice by individuals using Removable Partial Denture (RPD) is an important component of oral health measures. An assessment of denture care practice of such individuals by dental care practitioners is necessary. Objective: To evaluate the denture care practice among prosthetics patients attending a tertiary Hospital Dental Centre in Nigeria. Materials and Methods: An interviewer administered questionnaire was used to obtain information from RPD wearers that were willing to participate. The questionnaire assessed among other things, patients’ bio-data, frequency, techniques and device used for cleaning their dentures. Data was analyzed using Chi-square test (P < 0.05). Results: One hundred and ninety eight denture wearers consisting of 100 (50.5%) males and 98 (49.5%) females participated in the study. Majority 110 (55.6%) cleaned their dentures once daily and toothbrush and pastes were used by 105 (53%) of the participants. More than 70% of the respondents removed their dentures at night. One hundred and sixty-six (83.8%) visited the dentist only when they needed treatment. There was a statistical significant relationship between frequency and technique of cleaning denture, and denture cleanliness (P < 0.05). Conclusion: This study shows that once daily cleaning of dentures and cleaning the denture with rest of the teeth are ineffective in prevention of plaque accumulation. PMID:26229229

  8. Removable partial overdentures for the irradiated patient

    SciTech Connect

    Rosenberg, S.W. )

    1990-10-01

    Patients who have received radiotherapy to the head and neck area must avoid dental extractions and seek simplicity in treatment and home care follow-up. For partially edentulous patients, removable partial overdenture therapy can fulfill these goals while maintaining the high level of function and aesthetics desired by patients.11 references.

  9. FIBER-REINFORCED FIXED PARTIAL DENTURES: A PRELIMINARY RETROSPECTIVE CLINICAL STUDY

    PubMed Central

    Piovesan, Edno Moacir; Demarco, Flávio Fernando; Piva, Evandro

    2006-01-01

    The aim of this study was to evaluate the clinical performance (retention rate) of fiber-reinforced composite fixed partial dentures (FPDs). Polyethylene fiber (Ribbond®) was used combined with restorative composite during FPDs fabrication. FPDs were placed in thirteen patients in a private clinic. Nineteen FPDS were evaluated. The prosthetic space was filled with only one pontic using extracted teeth (2 cases), acrylic resin teeth (11 cases), or with composite resin (6 cases), combined with Polyethylene fiber. The clinical criterion used was based on retention rate of FPDs. If FPDs were in function in the mouth at the time of examination without previous repair they were classified as Complete Survival (CS) restorations. A classification of Survival with Rebonding (SR) was assigned in the event of an adhesive failure, but after rebonding the FPD still remained under evaluation. Treatment was classified as a Failure (F) if the FPD restoration was lost. The time of evaluation was 41.15 months (±15.13). The FPDs evaluated were retained (CS=94.75%), and no failure was found except for in one situation which required rebonding (SR=5.25%). According to the survival estimation method of Kaplan-Meyer the mean survival time was 42.3 months. At the time of evaluation investigated, polyethylene-reinforced FPDs showed a favorable retention rate in preliminary data. PMID:19089039

  10. Restoring Anterior Aesthetics by a Rotational Path Cast Partial Denture: An Overlooked Technique

    PubMed Central

    Bhat, Bala Saraswati; Arora, Himanshu

    2016-01-01

    Cast Partial Dentures (CPD) has long been known to restore missing teeth in patients with minimal invasion on hard and soft tissues. Although satisfactory otherwise, the main concern in CPD is the anterior display of metal. Also the technique sensitive lab procedures, together with the esthetic concern have built an iceberg around the frequent utilization of this treatment modality. With the advent of various techniques to get rid of the metallic display, it was predicted to have more CPD’s done in the dental arena. But the conceptual technicalities of the procedure took away the limelight from this treatment modality and focused on the fixed prosthodontics. Although feasible in a large number of patients, fixed prosthesis still has areas of restriction. It is here, when we apply our knowledge and skill of esthetic CPD. Esthetic CPD eliminates the metal display by utilizing desirable undercuts. The engaging action of the framework into these undercuts paves way for a rotational motion to seat the remaining prosthesis. Hence dual path of insertion helps eliminating the anterior clasp. In this case report dual path of insertion is discussed for replacing anterior teeth in an old male patient who had mild esthetic concerns. Following the conservative approach of CPD (over FPD) esthetic and restorative treatment was planned with patient’s consent. PMID:27437375

  11. Marginal adaptation analysis performed with en face optical coherence tomography in fixed partial dentures

    NASA Astrophysics Data System (ADS)

    Sinescu, Cosmin; Negrutiu, Meda Lavinia; Antonie, Sergiu; Dobre, George; Bradu, Adrian; Hughes, Michael; Rominu, Mihai; Podoleanu, Adrian Gh.

    2009-02-01

    Frameworks for fixed partial denture made out of dental alloys thought classic techniques currently involve many errors like marginal and internal gaps. The aim of this study is to present alternative technologies in making frameworks from dental alloys using selective laser sintering/ selective laser melting (SLS/ SLM) and to investigate the marginal adaptation of the fixed dental prostheses using the en face optical coherence tomography. These procedures imply the use of a scanning device PROBIS, SMART OPTICS with the help of 3D Dental Scanner software. For digitizing the 3D model we used the Dental Wings Kunde Software. The files obtained were sent to a SLS/ SLM machine, Hint-Els rapidPro, where the CoCr powder was sintered/melt by selectively consolidating successive layers of powder material on top of each other, using thermal energy supplied by a focused and computer controlled laser beam. Through this technique can be produced up to 80 pieces in only one step. A parallel between the classic casting technique and this new technology reveal the least has several advantages: fast finishing time, excellent marginal and internal fit, biocompatibility and superior chemical properties. SLS/ SLM proved to be a promising technology that may overcome the classic ones, because of the superior marginal fit of the fixed dental prostheses to the teeth.

  12. Bone's responses to different designs of implant-supported fixed partial dentures.

    PubMed

    Rungsiyakull, Chaiy; Chen, Junning; Rungsiyakull, Pimduen; Li, Wei; Swain, Michael; Li, Qing

    2015-04-01

    This paper explores the biomechanics and associated bone remodeling responses of two different abutment configurations, namely implant-implant-supported versus tooth-implant-supported fixed partial dentures. Two 3D finite element analysis models are created based upon computerized tomography data. The strain energy density induced by occlusal loading is used as a mechanical stimulus for driving the bone remodeling. To measure osseointegration and stability during healing, a resonance frequency analysis is conducted. At the second premolar peri-implant region, overloading resorption around the neck of implant is identified in both the models over the first 12 months. Stress-shielding around the edentulous region is also observed in both the models with a greater resorption rate found in the implant-implant case. The remodeling and resonance frequency analyses reveal that the tooth-implant scheme offers a higher degree of osseointegration. The remodeling procedure is expected to provide prosthodontists with a modeling tool to assess possible long-term clinical outcomes. PMID:25209424

  13. Fit of all-ceramic posterior fixed partial denture frameworks in vitro.

    PubMed

    Bindl, Andreas; Mörmann, Werner H

    2007-12-01

    The objective of this study was to evaluate, by scanning electron microscopy, the marginal and internal fit of all-ceramic three-unit fixed partial denture (FPD) frames fabricated by computer-assisted design/computer-aided machining (CAD/CAM) and CAM techniques using blocks of infiltration ceramic, high-strength yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) zirconia sinter ceramic, high-strength dense sintered Y-TZP zirconia ceramic, and glass ceramic. Slip-cast infiltration ceramic was used as a traditional control. The cementation interface widths of the FPD frame copings on butt (A) shoulders of Cerec In-Ceram zirconia (A1, 53 +/- 17 microm) were smaller than those of slip-cast In-Ceram zirconia (A6, 113 +/- 25 microm). Cerec Y-TZP zirconia (A2, 53 +/- 9 pm) and DCS Y-TZP zirconia (A4, 32 +/- 6 microm) interfaces were both significantly smaller than those of Cercon Y-TZP zirconia (A5, 120 +/- 6 microm). Internally, A2 (103 +/- 14) interfaces were smaller than A4 interfaces (144 +/- 15 microm). On chamfer shoulders (B), Cerec Y-TZP zirconia (B1, 71 +/- 5 microm) interfaces were smaller than Cercon interfaces (B2, 129 +/- 38 microm); internally, B1 (80 +/- 11 microm) interfaces were smaller than B2 interfaces (130 +/- 12 microm). CAD/CAM produced better marginal and internal accuracy of fit compared to slip casting and CAM techniques. PMID:18092451

  14. Clinical studies of fiber-reinforced resin-bonded fixed partial dentures: a systematic review.

    PubMed

    van Heumen, Céleste C M; Kreulen, Cees M; Creugers, Nico H J

    2009-02-01

    In the past decade, follow-up studies on fiber-reinforced composite fixed partial dentures (FRC FPDs) have been described. Combining the results of these studies to draw conclusions about the effectiveness of FRC FPDs is challenging. The objective of this systematic review was to obtain survival rates of FRC FPDs and to explore the relationships between reported survival rates and risk factors. In a literature-selection procedure on the clinical performance of FRC FPDs, 15 studies, reporting on 13 sets of patients, were analyzed. The Kaplan-Meier estimate of the overall survival, based on the data from all sets of patients (n = 435) was 73.4% (69.4-77.4%) at 4.5 yr. Converted survival rates at 2 yr of follow-up showed substantial heterogeneity between studies. It was not possible to build a reliable regression model that indicated risk factors. The technical problems most commonly described were fracture of the FPD and delamination of the veneering composite. PMID:19196311

  15. Restoring Anterior Aesthetics by a Rotational Path Cast Partial Denture: An Overlooked Technique.

    PubMed

    Sharma, Deeksha; Bhat, Bala Saraswati; Arora, Himanshu

    2016-05-01

    Cast Partial Dentures (CPD) has long been known to restore missing teeth in patients with minimal invasion on hard and soft tissues. Although satisfactory otherwise, the main concern in CPD is the anterior display of metal. Also the technique sensitive lab procedures, together with the esthetic concern have built an iceberg around the frequent utilization of this treatment modality. With the advent of various techniques to get rid of the metallic display, it was predicted to have more CPD's done in the dental arena. But the conceptual technicalities of the procedure took away the limelight from this treatment modality and focused on the fixed prosthodontics. Although feasible in a large number of patients, fixed prosthesis still has areas of restriction. It is here, when we apply our knowledge and skill of esthetic CPD. Esthetic CPD eliminates the metal display by utilizing desirable undercuts. The engaging action of the framework into these undercuts paves way for a rotational motion to seat the remaining prosthesis. Hence dual path of insertion helps eliminating the anterior clasp. In this case report dual path of insertion is discussed for replacing anterior teeth in an old male patient who had mild esthetic concerns. Following the conservative approach of CPD (over FPD) esthetic and restorative treatment was planned with patient's consent. PMID:27437375

  16. Clinical performance and failures of zirconia-based fixed partial dentures: a review literature

    PubMed Central

    Triwatana, Premwara; Nagaviroj, Noppavan

    2012-01-01

    PURPOSE Zirconia has been used in clinical dentistry for approximately a decade, and there have been several reports regarding the clinical performance and survival rates of zirconia-based restorations. The aim of this article was to review the literatures published from 2000 to 2010 regarding the clinical performance and the causes of failure of zirconia fixed partial dentures (FPDs). MATERIALS AND METHODS An electronic search of English peer-reviewed dental literatures was performed through PubMed to obtain all the clinical studies focused on the performance of the zirconia FPDs. The electronic search was supplemented by manual searching through the references of the selected articles for possible inclusion of some articles. Randomized controlled clinical trials, longitudinal prospective and retrospective cohort studies were the focuses of this review. Articles that did not focus on the restoration of teeth using zirconia-based restorations were excluded from this review. RESULTS There have been three studies for the study of zirconia single crowns. The clinical outcome was satisfactory (acceptable) according to the CDA evaluation. There have been 14 studies for the study of zirconia FPDs. The survival rates of zirconia anterior and posterior FPDs ranged between 73.9% - 100% after 2 - 5 years. The causes of failure were veneer fracture, ceramic core fracture, abutment tooth fracture, secondary caries, and restoration dislodgment. CONCLUSION The overall performance of zirconia FPDs was satisfactory according to either USPHS criteria or CDA evaluations. Fracture resistance of core and veneering ceramics, bonding between core and veneering materials, and marginal discrepancy of zirconia-based restorations were discussed as the causes of failure. Because of its repeated occurrence in many studies, future researches are essentially required to clarify this problem and to reduce the fracture incident. PMID:22737311

  17. Failure of all-ceramic fixed partial dentures in vitro and in vivo: analysis and modeling.

    PubMed

    Kelly, J R; Tesk, J A; Sorensen, J A

    1995-06-01

    Hertzian cone cracks visible at the loading site of 20 all-ceramic fixed partial dentures (FPDs), tested in vitro, led to the hypotheses that failure was due to the propagation of localized contact damage crack systems (Hertzian stress state) and that such damage was an unlikely clinical failure mode. Fractographic analysis of the 20 laboratory-failed and nine clinically-failed all-ceramic FPDs allowed for definitive testing of these hypotheses and a comparison between in vitro and in vivo failure behavior. In all cases, failure occurred in the FPD connectors (none from contact damage), with approximately 70 to 78% originating from the interface between the core and veneer ceramics. The coincidence between failure origins provides strong evidence that the in vitro test modeled aspects of structural behavior having clinical importance. The fractographic observations, coupled with the in vitro failure load data, furnished very specific boundary conditions which were applied to constrain mathematical models of FPD connector failure. Finite element analysis (FEA) of the laboratory FPDs found that maximum principal tensile stresses would occur at locations consistent with the fractographic observations only if: (1) there were appropriate elastic moduli differences between the ceramics; and (2) a small amount of abutment rotation was allowed. Weibull failure probability (Pf) calculations, incorporating FEA stress profiles, very closely replicated the laboratory failure distribution only when: (1) the veneer ceramic was much weaker than the core ceramic; and (2) the Weibull modulus of the core-veneer interface was much lower than that for the free veneer surface (i.e., the interface is of lower quality with regard to defects).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7629333

  18. Effect of polyester fiber reinforcement on the mechanical properties of interim fixed partial dentures

    PubMed Central

    Gopichander, N.; Halini Kumarai, K.V.; Vasanthakumar, M.

    2015-01-01

    Background Different reinforcements currently available for interim fixed partial denture (FPD) materials do not provide the ideal strength for long-term use. Therefore, the aim of this investigation was to develop a more ideal provisional material for long-term use with better mechanical properties. This study evaluated the effectiveness of polyester fiber reinforcement on different interim FPD materials. Methods Thirty resin-bonded FPDs were constructed from three provisional interim FPD materials. Specimens were tested with a universal testing machine (UTM). The modulus of elasticity and flexural strength were recorded in MPa. The compressive strength and degree of deflection were calculated from the obtained values, and a two-way analysis of variance (ANOVA) was used to determine the significance. Results The polyester fiber reinforcement increased the mechanical properties. The modulus of elasticity for heat-polymerized polymethyl methacrylate (PMMA) was 624 MPa, compared to 700.2 MPa for the reinforced heat-cured sample. The flexural strengths of the bis-acrylic and cold-polymerized reinforced samples increased significantly to 2807 MPa and 979.86 MPa, respectively, compared to the nonreinforced samples. The mean compressive strength of the reinforced cold-polymerized PMMA samples was 439.17 MPa; and for the reinforced heat-polymerized PMMA samples, it was 1117.41 MPa. The degree of deflection was significantly greater (P < 0.05) in the reinforced bis-acrylic sample (5.03 MPa), compared with the nonreinforced bis-acrylic sample (2.95 MPa). Conclusion Within the limitations of this study, polyester fiber reinforcements improved the mechanical properties of heat-polymerized PMMA, cold-polymerized PMMA, and bis-acrylic provisional FPD materials. PMID:26644754

  19. Evaluation of the adaptation of zirconia-based fixed partial dentures using micro-CT technology.

    PubMed

    Borba, Márcia; Miranda, Walter Gomes; Cesar, Paulo Francisco; Griggs, Jason Allan; Bona, Alvaro Della

    2013-01-01

    The objective of the study was to measure the marginal and internal fit of zirconia-based all-ceramic three-unit fixed partial dentures (FPDs) (Y-TZP - LAVA, 3M-ESPE), using a novel methodology based on micro-computed tomography (micro-CT) technology. Stainless steel models of prepared abutments were fabricated to design FPDs. Ten frameworks were produced with 9 mm2 connector cross-sections using a LAVATM CAD-CAM system. All FPDs were veneered with a compatible porcelain. Each FPD was seated on the original model and scanned using micro-CT. Files were processed using NRecon and CTAn software. Adobe Photoshop and Image J software were used to analyze the cross-sectional images. Five measuring points were selected, as follows: MG - marginal gap; CA - chamfer area; AW - axial wall; AOT - axio-occlusal transition area; OA - occlusal area. Results were statistically analyzed by Kruskall-Wallis and Tukey's post hoc test (α= 0.05). There were significant differences for the gap width between the measurement points evaluated. MG showed the smallest median gap width (42 µm). OA had the highest median gap dimension (125 µm), followed by the AOT point (105 µm). CA and AW gap width values were statistically similar, 66 and 65 µm respectively. Thus, it was possible to conclude that different levels of adaptation were observed within the FPD, at the different measuring points. In addition, the micro-CT technology seems to be a reliable tool to evaluate the fit of dental restorations. PMID:24036977

  20. In vitro Evaluation of the Accuracy of Seating Cast Metal Fixed Partial Denture on the Abutment Teeth with Varying Degree of Convergence Angle

    PubMed Central

    Tatikonda, Aravind; Raina, Seema; Gubrellay, Priyanka; Gupta, Naveen; Asopa, Swati Joshi

    2015-01-01

    Background The prime goal of a diligent prosthodontist is to obtain adequate marginal fit while restoring lost tooth structure. The marginal fit of the restoration, in turn depends upon the geometrical morphology of the tooth preparation. Objective To determine the effect of varying degree of convergence angle on the marginal seating of the single crown, three-unit fixed partial denture and multiple-unit fixed partial denture with pier abutment. Materials and Methods Three dies, of same convergence angle, were placed in an arch form on a base. In this way, four arch forms were prepared for four different convergence angles i.e. 0°, 6°, 12°, and 20°. Five castings each were made for single crown, 3-unit fixed partial denture and multiple-unit fixed partial denture (FPD) with pier abutment for each convergence angle. The castings were seated on their respective dies and vertical marginal discrepancy was measured at four points for each casting with the help of an optical microscope. Results The results showed that 200 convergence angle showed better marginal seating of the single crown, 3-unit FPD as well as for the multiple unit FPD. Conclusion There was a possibility that the retention and resistance may be compromised with 200 taper. Hence 120 taper is suggested for crowns and fixed partial denture retainers as the marginal discrepancy is reasonable and retention and resistance is optimum. There was a high statistical significant difference in the values obtained for the different convergence angles. PMID:26393207

  1. The influence of interproximal contact on implant-supported fixed partial dentures in the posterior jaw: a photoelastic analysis.

    PubMed

    Naves, Marina Melo; de Menezes, Helder Henrique Machado; de Magalhães, Denildo; de Araújo, Cleudmar Amaral; Júnior, Paulo Cézar Simamoto

    2015-02-01

    The aim of this study was to analyze the effect of the separation of prosthetic crowns from fixed partial dentures by means of stress gradient evaluation. Three photoelastic models were created to examine contiguous implants with varying contact between the crowns (contact point [CP], contact surface [CS], splinted [SP]). The SP group presented the best results, followed by the CS group, indicating that the use of splinted prosthetic crowns and crowns with broad surface contacts is viable when considering the stress values. PMID:23397888

  2. Comparative Evaluation of Marginal Accuracy of a Cast Fixed Partial Denture Compared to Soldered Fixed Partial Denture Made of Two Different Base Metal Alloys and Casting Techniques: An In vitro Study.

    PubMed

    Jei, J Brintha; Mohan, Jayashree

    2014-03-01

    The periodontal health of abutment teeth and the durability of fixed partial denture depends on the marginal adaptation of the prosthesis. Any discrepancy in the marginal area leads to dissolution of luting agent and plaque accumulation. This study was done with the aim of evaluating the accuracy of marginal fit of four unit crown and bridge made up of Ni-Cr and Cr-Co alloys under induction and centrifugal casting. They were compared to cast fixed partial denture (FPD) and soldered FPD. For the purpose of this study a metal model was fabricated. A total of 40 samples (4-unit crown and bridge) were prepared in which 20 Cr-Co samples and 20 Ni-Cr samples were fabricated. Within these 20 samples of each group 10 samples were prepared by induction casting technique and other 10 samples with centrifugal casting technique. The cast FPD samples obtained were seated on the model and the samples were then measured with travelling microscope having precision of 0.001 cm. Sectioning of samples was done between the two pontics and measurements were made, then the soldering was made with torch soldering unit. The marginal discrepancy of soldered samples was measured and all findings were statistically analysed. The results revealed minimal marginal discrepancy with Cr-Co samples when compared to Ni-Cr samples done under induction casting technique. When compared to cast FPD samples, the soldered group showed reduced marginal discrepancy. PMID:24605006

  3. Oral health-related quality of life in patients with removable dentures.

    PubMed

    Pistorius, Jutta; Horn, Jan G; Pistorius, Alexander; Kraft, Joachim

    2013-01-01

    The purpose of this study was to determine factors that affected oral health-related quality of life (Oral Health Related Quality of Life = OHRQoL) in patients with removable dentures (RD). Quality of life was evaluated by using the Geriatric Oral Health Assessment Index (GOHAI). We analysed data of 250 patients aged 63 ± 11.6 years. After excluding patients lacking relevant analysis data, 243 patients remained in the study, including 129 males and 114 females. Relevant parameters for good OHRQoL were: patient satisfaction with their RD (r = -0.317), higher age (r = 0.222), greater number of remaining teeth (r = 0.357), higher income (r = 0.175), higher frequency of dental visits (r = -0.212), tobacco abstinence (r = -0.181), and residence in a rural area (r = -0.420). Also, marital status had an impact on OHRQoL. Widowed and married patients showed the highest values and unmarried patients the lowest. Frequently mentioned problem areas considered within the survey were: the patient's fear of further tooth loss, concerns about functional aspects such as the decrease in chewing efficiency and dissatisfaction with the aesthetics of the dental prostheses. The results showed that the OHRQoL is apparently not only influenced by dental factors, but also by psychosocial and economic factors, the relevance of which would have to be shown in further studies. PMID:24420442

  4. The effect of fiber reinforcement type and water storage on strength properties of a provisional fixed partial denture resin.

    PubMed

    Uzun, Gülay; Keyf, Filiz

    2003-04-01

    Fracture resistance of provisional restorations is an important clinical concern. This property is directly related to transverse strength. Strengthening of provisional fixed partial dentures may result from reinforcement with various fiber types. This study evaluated the effect of fiber type and water storage on the transverse strength of a commercially available provisional resin under two different conditions. The denture resin was reinforced with either glass or aramid fiber or no reinforcement was used. Uniform samples were made from a commercially available autopolymerizing provisional fixed partial denture resin. Sixteen bar-shaped specimens (60 x 10 x 4 mm) were reinforced with pre-treated epoxy resin-coated glass fibers, with aramid fibers, or with no fibers. Eight specimens of each group, with and without fibers, were tested after 24 h of fabrication (immediate group), and after 30-day water storage. A three-point loading test was used to measure the transverse strength, the maximal deflection, and the modulus of elasticity. The Kruskal-Wallis Analysis of Variance was used to examine differences among the three groups, and then the Mann-Whitney U Test and Wilcoxon Signed Ranks Test were applied to determine pair-wise differences. The transverse strength and the maximal deflection values in the immediate group and in the 30-day water storage group were not statistically significant. In the group tested immediately, the elasticity modulus was found to be significant (P = 0.042). In the 30-day water storage group, all the values were statistically insignificant. The highest transverse strength was displayed by the glass-reinforced resin (66.25MPa) in the immediate group. The transverse strength value was 62.04MPa for the unreinforced samples in the immediate group. All the specimens exhibited lower transverse strength with an increase in water immersion time. The transverse strength value was 61.13 MPa for the glass-reinforced resin and was 61.24 MPa for the

  5. An in vitro study into the effect of a limited range of denture cleaners on surface roughness and removal of Candida albicans from conventional heat-cured acrylic resin denture base material.

    PubMed

    Harrison, Z; Johnson, A; Douglas, C W I

    2004-05-01

    This study evaluated the abrasiveness of four denture cleaners on the surface of denture base material and assessed their ability to remove Candida albicans. Acrylic resin discs 20 mm diameter and 2 mm thick were identically produced and polished. Four cleaners were evaluated: conventional toothpaste; toothpaste with stain remover; denture cleaning paste and an immersion type cleaner, and water were used as control. These were used at dilutions of 1:1, 1:2 and 1:3 with water. An electric toothbrush was used, and the discs cleaned to simulate 1 years' cleaning. The surface roughness of the discs were then measured, before and after cleaning, using a stylus profilometer, then inoculated with 1.2 x 10(6)C. albicans cells. The effectiveness of the denture cleaners to remove C. albicans cells was assessed following a single cleaning event. The immersion cleaner was significantly less abrasive than paste cleaners (P < 0.05). There were no significant differences between any dilutions for any cleaner used (P > 0.05). Immersion and paste cleaners removed almost all recoverable C. albicans from the discs, as cleaning with water alone was less effective (P < 0.05). An immersion type cleaner was found to be the most suitable cleaner because of its low abrasivity and effective removal of organic debris. PMID:15140172

  6. Periodontal considerations of the removable partial overdenture.

    PubMed

    Gomes, B C; Renner, R P

    1990-10-01

    1. An overdenture, whether complete or partial, is an excellent mode of treatment in the mutilated dentition for the preservation of the residual ridge. 2. Selection of patients for an overdenture should be based on past history of dental neglect, the status of the teeth and their periodontium, including present oral hygiene status, and patient motivation. The patients with a history of dental neglect, poor oral hygiene, and lack of motivation in having the teeth and the periodontium restored to health as well as strict compliance to a home-care regimen and recall schedule are not good candidates for treatment with an overdenture. 3. The choice of teeth or roots to serve as overdenture abutments must include their periodontal evaluation, which should consist of a detailed periodontal examination, diagnosis, prognosis, and treatment when this is indicated, including chemical protection (fluoride gel) and an oral hygiene regimen tailored to individual needs. 4. The knowledge and expertise in the selection and implementation of appropriate periodontal treatment modalities is of paramount importance in restoring optimum periodontal health to the overdenture abutments before overdenture fabrication. 5. The maintenance phase of the overdenture abutments as well as of the existing natural teeth is of critical importance in the preservation of health of these abutments and teeth. This maintenance phase should consist of periodic recalls based on individual needs; a detailed periodontal evaluation, including patient's motivation and status of oral hygiene and denture hygiene; and detection of caries. If necessary, appropriate periodontal and/or restorative therapy should be performed, and oral hygiene measures reinforced. This will ensure longevity of both abutment teeth or roots and of the existing natural teeth resulting in a long-term success of an overdenture. 6. Because there is evidence of high incidence of periodontal disease and dental caries in overdenture wearers

  7. Application of cast iron-platinum keeper to a collapsible denture for a patient with constricted oral opening: a clinical report.

    PubMed

    Ohkubo, Chikahiro; Watanabe, Ikuya; Tanaka, Yasuhiro; Hosoi, Toshio

    2003-07-01

    Insertion of a denture is especially difficult for patents with a constricted oral opening. This report describes the fabrication of a collapsible removable partial denture with a cast iron-platinum attachment for a partially edentulous woman with a constricted oral opening resulting from rheumatoid arthritis and a craniotomy for a subarachnoid hemorrhage. PMID:12869968

  8. Full mouth rehabilitation of a patient with mandibular implant screw retained Fp-3 prosthesis opposing maxillary acrylic removable over-denture

    PubMed Central

    Jain, Ashish R.; Nallaswamy, Deepak; Ariga, Padma; Philip, Jacob Mathew

    2013-01-01

    A hybrid denture is one that is fabricated over a metal framework and retained by screws threaded into the implant abutments. The anterior part of a mandibular hybrid denture is fixed on implants while the posterior part of the denture is extended and cantilevered from implants. This article presents the fabrication of a maxillary over-denture opposing mandibular implant retained hybrid prosthesis. A total of four implants were placed in the mandibular arch. Castable abutments were used to produce the optimal angulations. Framework was waxed, cast recovered, and the fit was refined until the framework seated passively on the master cast. The mandibular denture teeth were waxed to the hybrid framework, and a final wax try-in was performed to verify and correct maxillomandibular relations before processing. The prosthesis was inserted after verification of occlusion, retention, and stability. The rehabilitation of edentulous patients with hybrid dentures has been observed to achieve greater masticatory function and psychological satisfaction than with conventional over-dentures. Producing a passive-fitting substructure for a fixed removable screw retained hybrid prosthesis is arguably one of the most technically complex tasks in implant dentistry. The technique presented may not initially produce a perfectly passive framework, but use of disclosing media and adjusting the internal aspect of the casting can result in non-binding, fully seated prostheses. PMID:24015016

  9. The Resin-Bonded Fixed Partial Denture as the First Treatment Consideration to Replace a Missing Tooth.

    PubMed

    Kuijs, Ruud; van Dalen, Andy; Roeters, Joost; Wismeijer, Daniel

    2016-01-01

    The resin-bonded fixed partial denture (RB-FPD) is the first restorative treatment option to be considered in cases where one or more teeth are missing. The indications for implants, conventional FPDs, and adhesive FPDs, considering the general and dental conditions of the patient, are discussed in this article. When the RB-FPD is the chosen option, a direct or indirect technique, a cantilever-type or fixed-fixed design, and materials to be used need to be selected. The choice will depend on a variety of factors, such as interproximal space at the connector area, anterior or posterior location, the skills of the dentist, esthetics, and the patient's wishes. The RB-FPD can be made using various techniques and materials. PMID:27479338

  10. Effects of mechanical properties of adhesive resin cements on stress distribution in fiber-reinforced composite adhesive fixed partial dentures.

    PubMed

    Yokoyama, Daiichiro; Shinya, Akikazu; Gomi, Harunori; Vallittu, Pekka K; Shinya, Akiyoshi

    2012-01-01

    Using finite element analysis (FEA), this study investigated the effects of the mechanical properties of adhesive resin cements on stress distributions in fiber-reinforced resin composite (FRC) adhesive fixed partial dentures (AFPDs). Two adhesive resin cements were compared: Super-Bond C&B and Panavia Fluoro Cement. The AFPD consisted of a pontic to replace a maxillary right lateral incisor and retainers on a maxillary central incisor and canine. FRC framework was made of isotropic, continuous, unidirectional E-glass fibers. Maximum principal stresses were calculated using finite element method (FEM). Test results revealed that differences in the mechanical properties of adhesive resin cements led to different stress distributions at the cement interfaces between AFPD and abutment teeth. Clinical implication of these findings suggested that the safety and longevity of an AFPD depended on choosing an adhesive resin cement with the appropriate mechanical properties. PMID:22447051

  11. [Clinical reasoning of impact of contemporary partial dentures constructions on the condition of periodontal tissues of patients with generalized periodontitis of I-II severity].

    PubMed

    Kochkina, N A

    2014-12-01

    The aim of the study was the evaluation of the effectiveness of using partial dentures made of thermoplastic materials for patients with generalized periodontitis of I-II degree of severity based on the results of clinical research. The effect of partial dentures made of acrylic, metal and thermoplastic materials with and without splinting elements of fixation on the state of periodontal tissues in patients with generalized periodontitis was studied. The results of clinical studies of patients periodontal tissues condition ,who have had dental defects on the background I-II severity of GP using partial splinting elements of fixation showed a significant improvement in oral hygiene, positive change in activity indicators current of generalized periodontitis. The group of patients for whom were made orthopedic constructions of thermoplastic masses, noticed reducing of the depth of periodontal pockets, tooth mobility, bleeding and inflammation of the interdental papillae and the gingival margin. PMID:25617097

  12. Effect of masticatory load on crack deflection/penetration investigated with en-face optical coherence tomography in ceramic fixed partial dentures

    NASA Astrophysics Data System (ADS)

    Sinescu, Cosmin; Negrutiu, Meda Lavinia; Marsavina, Liviu; Negru, Radu; Hluscu, Mihai; Caplescu, Cristiana; Bradu, Adrian; Hughes, Michael; Rominu, Mihai; Podoleanu, Adrian Gh.

    2009-02-01

    Optical Coherence Tomography (OCT) allows a better characterization of dental prostheses. The detection of substance defects within the ceramic layers for metal-ceramic prostheses was demonstrated. The detected defects have a large volume and therefore there is a high likelihood for fracture lines to be generated in the proximal areas of the ceramic fixed partial dentures. If the detection of such defects is feasible before inserting the prosthesis into the oral cavity, then timely corrective measures are possible in order to avoid the fracture of the ceramic component later on. After noninvasive localization of cracks in ceramic fixed partial dentures, the effect of the biaxial loading on crack deflection/penetration at the ceramic interface was investigated. A biaxial loaded geometry was numerically investigated using Finite Element Analysis in order to determine the energy release rate. The obtained results could be used in conjunction with criteria at interface for estimating the path of the crack after the interface was reached.

  13. Removable partial overdentures with mechanical (precision) attachments.

    PubMed

    Mensor, M C

    1990-10-01

    Mechanical attachments for overdentures have been available in various forms for over a century. The explosive interest in osseointegration and the effort on the part of the profession to avoid the complete denture as a treatment modality has stirred the interest in positive retentive elements for overdentures represented by the mechanical stud and bar attachments. The cited references provide a resource as a trouble-free guide in the selection and use of the various stud and bar attachment systems. The clinical examples show a pattern of application not generally discussed by the manufacturers, illustrating the simplicity of use with the options for all attachments including magnets. The discussion on magnets comes from 9 years of clinical experience. Rare earth magnets provide excellent adjunct retention, and their assembly follows the same protocol and complexity as stud attachment systems. All magnets, at the present state of the art, have a corrosion potential with the exception of the Laser Sealed Units (Golden Dental, Golden, CO). Finally, the mechanics of the attachment overdenture serves as an excellent training field for the osseointegrated prosthesis, be it the classic Brånemark (Nobelpharma USA, Chicago, IL) restorative or the implant overdenture concept. PMID:2227040

  14. Effect of Connector Design on Fracture Resistance in Zirconia-based Fixed Partial Dentures for Upper Anterior Region.

    PubMed

    Ogino, Yasushi; Nomoto, Syuntaro; Sato, Toru

    2016-01-01

    The purpose of this study was to investigate the influence of the cross-sectional form and area of the connector on fracture resistance in three-unit zirconia fixed partial denture (FPD) frameworks for the upper anterior region. Sixty FPD framework specimens were fabricated using the CAD/CAM system. The cross-sectional form (Type I, II, or III) and area (9.0, 7.0, 5.0, or 3.0 mm(2)) of the connectors differed. The specimens were fixed to a jig capable of applying a load axially to the abutment teeth at an angle of 135 degrees. Each specimen was subjected to fracture load measurements using a universal testing machine and cross-sectional microscopic examination. Fracture load fell significantly with a decrease in cross-sectional area (p <0.01). In terms of cross-sectional form, an isosceles triangle with a gingival base yielded the highest fracture load. These results suggest that the connector of a three-unit zirconia-based FPD framework for the upper anterior region should be triangular, have a gingival base, sufficient height in the loading direction, and a cross-sectional area of >5.0 mm(2). PMID:27320295

  15. The Effect of Different Fiber Concentrations on the Surface Roughness of Provisional Crown and Fixed Partial Denture Resin

    PubMed Central

    Zortuk, Mustafa; Kılıc, Kerem; Uzun, Gulay; Ozturk, Ahmet; Kesim, Bulent

    2008-01-01

    Objectives The aim of this study was to investigate surface roughness in provisional crown acrylics, after polishing, reinforced with different concentrations of glass fibers. Methods A total of 48 disk-shaped specimens were prepared using autopolymerizing acrylic resin. These specimens were divided into four groups according to the level of glass fiber added: Group A (no fiber), Group B (0.5%), Group C (1%) and Group D (2%). After polishing the specimens, an average surface roughness (Ra) value was calculated using a profilometer from four randomly selected points on the surface. Results A significant difference was determined among the surface roughness values of provisional crown resins to which different concentrations of fiber had been added (P<.001). Tukey’s test was then used to perform paired comparisons of the data between the different groups, and a significant difference was found between Group A (no fiber) and the other groups, between Group B (0.5%) and Group D (2%) and between Group C (1%) and Group D. On the other hand, there was no significant difference between Group B and Group C. Conclusions The reinforcement of provisional crown and fixed partial denture resin with glass fibers increases surface roughness. PMID:19212545

  16. Prevalence of single crowns and fixed partial dentures in elderly citizens in the southern and northern parts of Finland.

    PubMed

    Näpänkangas, R; Haikola, B; Oikarinen, K; Söderholm, A-L; Remes-Lyly, T; Sipilä, K

    2011-05-01

    The epidemiology of oral rehabilitation using fixed prosthodontics has received little attention. The aim of this study was to evaluate the prevalence of single crowns, fixed partial dentures (FPDs), resin-bonded FPDs and implants in elderly Finnish patients and to identify factors that might be associated with the findings. The survey was carried out in the southern and northern parts of Finland. The target population consisted of all persons born in 1919, 1922, 1925, 1928, 1931, 1934 and 1937, who lived in Kirkkonummi and in Lakeus (n=1733) in 1996. The age range of the subjects was 60-78years. In addition to a clinical examination, panoramic radiograph was taken. Data on background factors were obtained using questionnaires and/or interviews. The presence of single crowns, FPDs, resin-bonded FPDs and implants were determined from the panoramic radiographs. Overall, 12·4% of men and 12·1% of women had single crowns, while 4·8% of men and 8·0% of women had FPDs. A logistic regression analysis showed that the presence of crowns and FPDs was significantly associated with a southern place of residence, high and middle levels of education and high frequency of dental visits. PMID:20849471

  17. Technique for fabricating individualized dentures with a gingiva-shade composite resin.

    PubMed

    Park, Beom-Woo; Kim, Nam-Jin; Lee, Jonghyuk; Lee, Hae-Hyoung

    2016-05-01

    More natural dental esthetics have been sought by patients who wear conventional complete or partial dentures. Recently, gingiva-shade composite resins (GSCRs) have become available for replicating soft tissue for both fixed and removable prostheses. The technique presented is for fabricating individualized complete dentures. First the acrylic resin is mixed with a coloring agent and processed to modify the base shade of the denture. GSCRs are light polymerized onto a prepared space on the buccal surfaces of denture base to replicate the appearance of gingival tissues including blood vessels. The technique provides an outstanding natural, gingiva-like, appearance and allows complete dentures to harmonize with the individual patient's surrounding oral tissues. PMID:26794697

  18. Magnet and Semi Precision Attachment in an Implant Retained Partial Denture for the Rehabilitation of an Irradiated Marginal Mandibulectomy Patient: A Case Report

    PubMed Central

    Guttal, Satyabodh Shesharaj; Kulkarni, Sudhindra S; Kudva, Adarsh; Thakur, Srinath

    2015-01-01

    Surgical treatment of malignancies in the oral cavity (mandible, tongue, floor of the mouth, alveolus, buccal sulcus) often results in an unfavourable anatomic condition for prosthodontic rehabilitation. Hence, maxillofacial prosthetic rehabilitation becomes a mightier task when resection is accompanied by radiation therapy. In selected cases, implant therapy comes to rescue. The following report throws light on the case of prosthetic rehabilitation of a patient who underwent right marginal mandibulectomy and right partial glossectomy, with the aid of a single implant, semi precision attachment and magnet supported partial denture. PMID:26501028

  19. Fracture Resistance of Composite Fixed Partial Dentures Reinforced with Pre-impregnated and Non-impregnated Fibers

    PubMed Central

    Mosharraf, Ramin; Torkan, Sepideh

    2012-01-01

    Background and aims The mechanical properties of fiber-reinforced composite fixed partial dentures (FPDs) are af-fected by fiber impregnation. The aim of this in vitro study was to compare the fracture resistance of composite fixed partialdentures reinforced with pre-impregnated and non-impregnated fibers. Materials and methods Groups (n=5) of three-unit fiber-reinforced composite FPDs (23 mm in length) from maxillary second premolar to maxillary second molar were fabricated on two abutments with pontic width of 12 mm. One group was fabricated as the control group with composite (Gradia) and the other two groups were fabricated with composite (Gradia) reinforced with pre-impregnated fiber (Fibrex ribbon) and non-impregnated fiber (Fiber braid), respectively. The specimens were stored in distilled water for one week at 37°C and then tested in a universal testing machine by means of a three-point bending test. Statistical analysis consisted of one-way ANOVA and a post hoc Scheffé’s test for the test groups (α=0.05). Results Fracture resistance (N) differed significantly between the control group and the other two groups (P<0.001), but there were no statistically significant differences between the pre-impregnated and non-impregnated groups (P=0.565). The degree of deflection measured (mm) did not differ significantly between the three groups (P=0.397), yet the mean deflection measured in pre-impregnated group was twice as that in the other two groups. Conclusion Reinforcement of composite with fiber might considerably increase the fracture resistance of FPDs; how-ever, the type of the fiber used resulted in no significant difference in fracture resistance of FPD specimens. PMID:22991628

  20. A Review on Denture Marking Systems: A Mark in Forensic Dentistry.

    PubMed

    Kareker, Nikita; Aras, Meena; Chitre, Vidya

    2014-12-01

    "Identification through forensic science is an art of giving the corpse a name A real life detective work that would put even Sherlock Homes to shame." Forensic dentistry deals with proper handling and examination of dental evidence and proper evaluation and presentation of dental findings in interest of justice. The Prosthodontists are playing a very important role in forensic dentistry as they are concerned with fabrication of various prosthesis which can serve as an important tool for identification. Identification is essential requirement of any medico-legal investigation because a wrong identity may pose a problem in delivering justice. This article describes the different methods for identification/marking of the complete dentures, removable partial dentures and fixed partial dentures and the importance of denture marking in forensic investigatory purposes. The PubMed, Ebsco and Google search engines were used to gather the articles. PMID:26199485

  1. 3D Finite Element Study on: Bar Splinted Implants Supporting Partial Denture in the Reconstructed Mandible

    PubMed Central

    El-Anwar, Mohamed; Ghali, Rami; Aboelnagga, Mona

    2016-01-01

    AIM: This study aimed to estimate the stress patterns induced by the masticatory loads on a removable prosthesis supported and retained by bar splinted implants placed in the reconstructed mandible with two different clip materials and without clip, in the fibula-jaw bone and prosthesis using finite element analysis. METHODS: Two 3D finite element models were constructed, that models components were modeled on commercial CAD/CAM software then assembled into finite element package. Vertical loads were applied simulating the masticatory forces unilaterally in the resected site and bilaterally in the central fossa of the lower first molar as 100N (tension and compression). Analysis was based on the assumption full osseointegration between different types of bones, and between implants and fibula while fixing the top surface of the TMJ in place. RESULTS: The metallic bar connecting the three implants is insensitive to the clips material. Its supporting implants showed typical behavior with maximum stress values at the neck region. Fibula and jaw bone showed stresses within physiologic, while clips material effect seems to be very small due to its relatively small size. CONCLUSION: Switching loading force direction from tensile to compression did-not change the stresses and deformations distribution, but reversed their sign from positive to negative. PMID:27275353

  2. Swallowed dentures: Two cases and a review

    PubMed Central

    Gachabayov, Mahir; Isaev, Mubariz; Orujova, Lala; Isaev, Emin; Yaskin, Evgeniy; Neronov, Dmitriy

    2015-01-01

    Introduction Denture ingestion or aspiration is a problem requiring awareness of different specialists including dentists, surgeons, otolaryngologists, anesthesiologists etc. in terms of prevention, early diagnosis and adequate treatment. Complications of swallowed dentures include hollow viscus necrosis, perforation, penetration to neighbor organs leading to fistulae, bleeding and obstruction. Presentation of cases First case is a 54-year-old female who accidentally swallowed retractable one-tooth denture during fall about 22 h before admission and clinical manifestation of acute small bowel obstruction developed. The patient underwent laparotomy, enterotomy with retrieval of the foreign body. The second case is a 31-year-old male who accidentally ingested fixed one-tooth prosthesis while eating which impacted in the ileocaecal valve. During the preparation to colonoscopy the denture spontaneously passed out with stools. Discussion Denture ingestion is more common among patients with psychoneurologic deficit, alcohol and drug abusers. Among healthy and younger population denture ingestion is rare. Both reported patients are not elder. Thus dislodgement of removable or fixed dentures is another risk factor of denture ingestion. Most common site of denture impaction is esophagus; small bowel impaction is rare. Moreover, in most reported cases, small bowel impaction of ingested dentures leads to small bowel perforation. In our first case the complication of denture ingestion appeared to be bowel obstruction what is even rarer. Conclusion Fixed dentures can be accidentally ingested as well as removable dentures. Denture loosening leads to accidental denture ingestion. Patients with denture loosening should be recommended to visit dentist as soon as possible. PMID:26635957

  3. Fracture strength of three-unit fixed partial denture cores (Y-TZP) with different connector dimension and design.

    PubMed

    Bahat, Zdravko; Mahmood, Deyar J Hadi; Vult von Steyern, Per

    2009-01-01

    True crystalline ceramic materials presently used in restorative dentistry are Al2O3 (alumina) and yttrium-oxide stabilised tetragonal polycrystalline zirconium-dioxide (Y-TZP). To ensure optimal clinical performance, the dimensions of the Fixed Partial Denture (FPD) framework in general and of the connectors in particular, must be adequate. Considered recommendations for connector dimensions for Y-TZP FPDs vary from 2 to 4 mm in occluso-gingival height and 2 to 4 mm in bucco-lingual width. In order to reduce the fracture probability when designing all-ceramic FPDs, the shape of the connector is an important factor to consider. The radius of curvature at the gingival embrasure plays a significant role in the load-bearing capacity. FPDs with small gingival embrasure radii are subjected to high stress concentrations in the connector area during loading, compared to FPDs with large embrasure radii. The aim of this in-vitro study was to investigate how different radii of curvature in the embrasure of the connector area and different connector dimensions could affect the fracture resistance of 3-unit all-ceramic FPDs made of Y-TZP. Forty-eight FPDs in 6 groups of 8 FPDs with different connector design were produced in Procera Zirconia Bridge material. The FPD cores were subjected to heat treatment to simulate veneering. Following cementation, the FPDs were firstly thermocycled for 5,000 cycles, then preloaded for 10,000 cycles and finally loaded to fracture. All the FPDs fractured in the connector area. All the crack propagation which led to fracture started at the gingival embrasure of the connector. Within the limitations of this in-vitro study,the recommended minimum dimension of an anterior 3-unit all-ceramic FPD of Y-TZP is 3 mm in incisal-cervical direction and 2 mm in buccal-lingual direction. By increasing the radius of the gingival embrasure from 0.6 to 0.9 mm, the fracture strength for a Y-TZP FPD with connector dimension 3 x 3 mm increases by 20%. PMID

  4. Denture identification--a simple approach.

    PubMed

    Heath, J R

    1987-03-01

    In order to find a denture identification method that could be rapidly applied to completed dentures, a variety of spirit pens and commercial and experimental sealants were investigated. The pens were generally rapidly removed by one or more abrasive, denture cleansing, antiseptic or mouthwash agent; the sealants exhibited greater longevity. An experimental sealant (acrylic polymer dissolved in chloroform) was found to be cheap, readily prepared, easily applied, very resistant to abrasion, unaffected by immersion denture cleansers, antiseptics and mouthwashes, to produce no more crazing on dentures than the other sealants investigated, and not to affect the transverse strength of acrylic resin. PMID:3470464

  5. Effect of cantilever length and alloy framework on the stress distribution in peri-implant area of cantilevered implant-supported fixed partial dentures.

    PubMed

    Suedam, Valdey; Moretti Neto, Rafael Tobias; Sousa, Edson Antonio Capello; Rubo, José Henrique

    2016-04-01

    Because many mechanical variables are present in the oral cavity, the proper load transfer between the prosthesis and the bone is important for treatment planning and for the longevity of the implant-supported fixed partial denture. Objectives To verify the stress generated on the peri-implant area of cantilevered implant-supported fixed partial dentures and the potential effects of such variable. Material and Methods A U-shaped polyurethane model simulating the mandibular bone containing two implants (Ø 3.75 mm) was used. Six groups were formed according to the alloy's framework (CoCr or PdAg) and the point of load application (5 mm, 10 mm and 15 mm of cantilever arm). A 300 N load was applied in pre-determined reference points. The tension generated on the mesial, lingual, distal and buccal sides of the peri-implant regions was assessed using strain gauges. Results Two-way ANOVA and Tukey statistical tests were applied showing significant differences (p<0.05) between the groups. Pearson correlation test (p<0.05) was applied showing positive correlations between the increase of the cantilever arm and the deformation of the peri-implant area. Conclusions This report demonstrated the CoCr alloy shows larger compression values compared to the PdAg alloy for the same distances of cantilever. The point of load application influences the deformation on the peri-implant area, increasing in accordance with the increase of the lever arm. PMID:27119758

  6. The effect of aluminium on the metallography of a nickel base removable partial denture casting alloy.

    PubMed

    Lewis, A J

    1978-12-01

    Three special nickel-chromium alloys were prepared in which the aluminum levels were adjusted both above and below that of a commercial nickel base dental casting alloy. Tensile and metallographic evaluation of representative samples of the alloys were made and the changes in the properties of the alloys are reported. PMID:285671

  7. The effect of carbon on the metallography of a nickel base removable partial denture casting alloy.

    PubMed

    Lewis, A J

    1979-04-01

    This study has demonstrated the pattern of carbide development associated with progressive increases in carbon content in a series of six nickel chromium alloys. The carbon content is critical since it influences the production and distribution of carbides, which have been shown to alter the mechanical properties, of the nickel chromium alloys, that are dependent upon the development of gamma prime. Furthermore, it has been shown that the attainment of suitable strength is invariably associated with an unacceptable level of ductility. PMID:288385

  8. Fabrication of a maxillary posterior fixed partial denture with a type 4 gold alloy and a dual-polymerizing indirect composite.

    PubMed

    Matsumura, Hideo; Mori, Shuichi; Tanoue, Naomi

    2008-03-01

    The aim of the present study was to design and fabricate a maxillary posterior fixed partial denture (FPD) made of a type 4 gold alloy and an indirect composite. Unlike the conventional framework design of a resin veneered restoration, cut-back was extended approximately 1/4 to 1/3 width in the occlusal table of the buccal cusp. Multiple retentive beads 150-200 mum in diameter were placed on the metal surface to be veneered. The gold alloy was cast in a cristobalite mold using a centrifugal casting machine. The cut surface with the retentive beads was air-abraded with alumina, and a priming agent (Alloy Primer) that contained triazine dithione monomer (VTD) was applied. A tooth-colored veneer was then fabricated with a highly loaded light- and heat-cured composite material (Estenia). This design and procedure can be applied as a standardized laboratory technique for fabrication of maxillary posterior restorations and FPDs. PMID:18403895

  9. The Oral Microbiome of Denture Wearers Is Influenced by Levels of Natural Dentition

    PubMed Central

    O’Donnell, Lindsay E.; Robertson, Douglas; Nile, Christopher J.; Cross, Laura J.; Riggio, Marcello; Sherriff, Andrea; Bradshaw, David; Lambert, Margaret; Malcolm, Jennifer; Buijs, Mark J.; Zaura, Egija; Crielaard, Wim; Brandt, Bernd W.; Ramage, Gordon

    2015-01-01

    Objectives The composition of dental plaque has been well defined, whereas currently there is limited understanding of the composition of denture plaque and how it directly influences denture related stomatitis (DS). The aims of this study were to compare the microbiomes of denture wearers, and to understand the implications of these towards inter-kingdom and host-pathogen interactions within the oral cavity. Methods Swab samples were obtained from 123 participants wearing either a complete or partial denture; the bacterial composition of each sample was determined using bar-coded illumina MiSeq sequencing of the bacterial hypervariable V4 region of 16S rDNA. Sequencing data processing was undertaken using QIIME, clustered in Operational Taxonomic Units (OTUs) and assigned to taxonomy. The dentures were sonicated to remove the microbial flora residing on the prosthesis, sonicate was then cultured using diagnostic colorex Candida media. Samples of unstimulated saliva were obtained and antimicrobial peptides (AMP) levels were measured by ELISA. Results We have shown that dental and denture plaques are significantly distinct both in composition and diversity and that the oral microbiome composition of a denture wearer is variable and is influenced by the location within the mouth. Dentures and mucosa were predominantly made up of Bacilli and Actinobacteria. Moreover, the presence of natural teeth has a significant impact on the overall microbial composition, when compared to the fully edentulous. Furthermore, increasing levels of Candida spp. positively correlate with Lactobacillus spp. AMPs were quantified, though showed no specific correlations. Conclusions This is the first study to provide a detailed understanding of the oral microbiome of denture wearers and has provided evidence that DS development is more complex than simply a candidal infection. Both fungal and bacterial kingdoms clearly play a role in defining the progression of DS, though we were unable to

  10. Effect of cantilever length and alloy framework on the stress distribution in peri-implant area of cantilevered implant-supported fixed partial dentures

    PubMed Central

    SUEDAM, Valdey; MORETTI, Rafael Tobias; SOUSA, Edson Antonio Capello; RUBO, José Henrique

    2016-01-01

    ABSTRACT Because many mechanical variables are present in the oral cavity, the proper load transfer between the prosthesis and the bone is important for treatment planning and for the longevity of the implant-supported fixed partial denture. Objectives To verify the stress generated on the peri-implant area of cantilevered implant-supported fixed partial dentures and the potential effects of such variable. Material and Methods A U-shaped polyurethane model simulating the mandibular bone containing two implants (Ø 3.75 mm) was used. Six groups were formed according to the alloy’s framework (CoCr or PdAg) and the point of load application (5 mm, 10 mm and 15 mm of cantilever arm). A 300 N load was applied in pre-determined reference points. The tension generated on the mesial, lingual, distal and buccal sides of the peri-implant regions was assessed using strain gauges. Results Two-way ANOVA and Tukey statistical tests were applied showing significant differences (p<0.05) between the groups. Pearson correlation test (p<0.05) was applied showing positive correlations between the increase of the cantilever arm and the deformation of the peri-implant area. Conclusions This report demonstrated the CoCr alloy shows larger compression values compared to the PdAg alloy for the same distances of cantilever. The point of load application influences the deformation on the peri-implant area, increasing in accordance with the increase of the lever arm. PMID:27119758

  11. Role of implant configurations supporting three-unit fixed partial denture on mandibular bone response: biological-data-based finite element study.

    PubMed

    Yoda, N; Liao, Z; Chen, J; Sasaki, K; Swain, M; Li, Q

    2016-09-01

    Implant-supported fixed partial denture with cantilever extension can transfer the excessive load to the bone around implants and stress/strain concentration potentially leading to bone resorption. This study investigated the effects of implant configurations supporting three-unit fixed partial denture (FPD) on the stress and strain distribution in the peri-implant bone by combining clinically measured time-dependent loading data and finite element (FE) analysis. A 3-dimensional mandibular model was constructed based on computed tomography (CT) images. Four different configurations of implants supporting 3-unit FPDs, namely three implant-supported FPD, conventional three-unit bridge FPD, distal cantilever FPD and mesial cantilever FPD, were modelled. The FPDs were virtually inserted to the molar area in the mandibular FE models. The FPDs were loaded according to time-dependent in vivo-measured 3-dimensional loading data during chewing. The von Mises stress (VMS) and equivalent strain (EQS) in peri-implant bone regions were evaluated as mechanical stimuli. During the chewing cycles, the regions near implant necks and bottom apexes experienced high VMS and EQS than the middle regions in all implant-supported FPD configurations. Higher VMS and EQS values were also observed at the implant neck region adjacent to the cantilever extension in the cantilevered configurations. The patient-specific dynamic loading data and CT-based reconstruction of full 3D mandibular allowed us to model the biomechanical responses more realistically. The results provided data for clinical assessment of implant configuration to improve longevity and reliability of the implant-supported FPD restoration. PMID:27224022

  12. Biomechanical comparison of implant retained fixed partial dentures with fiber reinforced composite versus conventional metal frameworks: a 3D FEA study.

    PubMed

    Erkmen, Erkan; Meriç, Gökçe; Kurt, Ahmet; Tunç, Yahya; Eser, Atılım

    2011-01-01

    Fiber reinforced composite (FRC) materials have been successfully used in a variety of commercial applications. These materials have also been widely used in dentistry. The use of fiber composite technology in implant prostheses has been previously presented, since they may solve many problems associated with metal alloy frameworks such as corrosion, complexity of fabrication and high cost. The hypothesis of this study was that an FRC framework with lower flexural modulus provides more even stress distribution throughout the implant retained fixed partial dentures (FPDs) than a metal framework does. A 3-dimensional finite element analysis was conducted to evaluate the stress distribution in bone, implant-abutment complex and prosthetic structures. Hence, two distinctly different models of implant retained 3-unit fixed partial dentures, composed of Cr-Co and porcelain (M-FPD model) or FRC and particulate composite (FRC-FPD model) were utilized. In separate load cases, 300 N vertical, 150 N oblique and 60 N horizontal forces were simulated. When the FRC-FPD and M-FPD models were compared, it was found that all investigated stress values in the M-FPD model were higher than the values in the FRC-FPD model except for the stress values in the implant-abutment complex. It can be concluded that the implant supported FRC-FPD could eliminate the excessive stresses in the bone-implant interface and maintain normal physiological loading of the surrounding bone, therefore minimizing the risk of peri-implant bone loss due to stress-shielding. PMID:21094484

  13. [The dynamics of changes in rheological properties of oral fluid in patients with different levels of oral hygiene, using removable dentures].

    PubMed

    Mikhaylenko, T N; Ernestyuk, A M; Rozhko, N M

    2014-12-01

    The issue of changing the physical and physico-chemical characteristics of oral fluid and their dependence on the level of oral hygiene in patients with removable dentures, requires further study. Therefore, in 86 individuals with 138 removable dentures, and 34 patients who are dentally and somatically healthy, we have had studied the parameters of viscosity, velocity of salivation, pH and concentration of mucin. According to the results of the factor analysis, it was determined that 78.6% of the studied parameters were indicators of hygienic condition of oral cavity. On the basis of significant difference and the strength and direction of correlation between the studied parameters and values of the integral index of oral hygiene, it was found, that in patients without somatic pathology with proper oral hygiene, we observed the growth of the rate of salivation and pH(c1), and in case of improper hygienic condition - reducing rate of salivation and increasing concentration of mucin. In case of the presence of somatic pathology, with an improvement of oral hygiene, the growth of pH(c1) and reducing of concentration of mucin was observed. The deterioration of oral hygiene level led to the increase of the rate of viscosity and the reduction of the salivation rate. PMID:25617095

  14. The bond between acrylic resin denture teeth and the denture base: recommendations for best practice.

    PubMed

    Radford, D R; Juszczyk, A S; Clark, R K F

    2014-02-01

    Failure of the bond between denture teeth and base acrylic resin has been shown to be a cause of denture failure leading to inconvenience and costly repair. The optimal combination of acrylic resin denture tooth, denture base material, laboratory protocol and processing method has not yet been established. Extensive research enables the following recommendations for best practice to be made. Adopt practices that maximise the strength of the bond: select appropriate denture teeth; select base acrylic resin from the same manufacturer as the denture teeth; remove the glaze from ridgelaps of the denture teeth; apply monomer to the ridgelaps of the denture teeth before packing the base acrylic resin dough; use the manufacturers' recommended liquid/powder ratio; follow the manufacturers' recommended curing cycle; allow the flask to cool slowly and rest before deflasking. Adopt practices that avoid factors detrimental to bond strength: remove all traces of wax from the ridge laps of the denture teeth; remove all traces of mould seal from the ridgelaps of the denture teeth. It is evident that a number of factors are involved which may assist or prevent formation of an adequate bond, suggesting that attention to detail by the dental technician may be the most critical factor. PMID:24557385

  15. Denture Adhesives

    MedlinePlus

    ... bone and give temporary relief from loosening dentures. Zinc and Potential Risk Zinc is a mineral that is an essential ingredient for good health. ... in some dietary supplements. However, an excess of zinc in the body can lead to health problems ...

  16. [How up-to-date are metal-based resin-bonded fixed partial dentures in the era of full-ceramics and dental implants? A case report].

    PubMed

    Bühler-Frey, Christian; Marinello, Carlo P

    2011-01-01

    Regardless of the success of preventive measures the replace¬ment of missing teeth in young patients with caries-free dentitions is a daily challenge for the clinician. The decision-making process concerning the different treatment options is difficult, based on several equivalent solutions. Thereby the significance of minimal invasive approaches is steadily increasing. In indicated cases, resin-bonded fixed partial dentures which were introduced in the last century still represent a well documented and minimally invasive procedure, even in the era of dental implants. In this article, clinical aspects of a conventional, metal-based resin-bonded fixed partial dentures are discussed according to the current literature and the clinical steps are presented in a clinical case. PMID:21861250

  17. Inlay-fixed partial dentures adhesively retained and reinforced by glass fibers: clinical and scanning electron microscopy analysis after five years.

    PubMed

    Göhring, Till N; Roos, Malgorzata

    2005-02-01

    Fifty-three posterior glass fibre-reinforced composite inlay-fixed partial dentures (IFPDs) in 36 patients were followed for 5 yr. For statistical analysis, one IFPD per patient was randomly selected. The survival rate and influence of discrete predictors (gender, location) and continuous variables (age, abutment surfaces) were determined. Clinical observations were recorded by using modified United States Public Health System (USPHS) criteria. Replicas of 17 randomly selected abutments were analysed by scanning electron microscopy (SEM) for marginal adaptation and the results were compared by using a repeated-measures analysis of variance (anova). The main reason for failure was veneering material delamination from the framework. The cumulative survival rate after 5 yr was 73% (95% confidence interval: 57-89%) for not delaminating and 96% (95% confidence interval: 88-100%) for not debonding. No significant influence of the tested predictors was found. Significant changes between baseline USPHS criteria and counterparts recorded at recall were fractures of the veneering material (chipping), wear, surface texture, and staining. Significant margin changes were only found between baseline and 1 yr. Thereafter, marginal adaptation remained stable. After 5 yr, 90% of the margins were termed as perfect. It was concluded that hard-tissue saving IFPDs with the current design maintained acceptable retention and marginal integrity. Future studies should aim at reducing delaminations by searching for improved framework designs and materials. PMID:15693831

  18. Bone metabolism induced by denture insertion in positron emission tomography.

    PubMed

    Suenaga, H; Chen, J; Yamaguchi, K; Sugazaki, M; Li, W; Swain, M; Li, Q; Sasaki, K

    2016-03-01

    18F-fluoride positron emission tomogra-phy (PET) can identify subtle functional variation prior to the major structural change detectable by X-ray. This study aims to investigate the mechanobiological bone reaction around the abutment tooth and in the residual ridge, induced by insertion of removable partial denture (RPD) within two different groups of patients: patients without denture experience (Group 1) and patients with denture experience before (Group 2), using 18F-fluoride PET imaging technique. 18F-fluoride PET/computerised tomography (CT) scan was performed to examine the bone metabolic change in mandible before and after the RPD treatment. Region of interests (ROIs) were placed in alveolar bone around abutment tooth and in residual bone beneath the RPD. Standardised uptake value (SUV), reflecting the accumulation of 18F-fluoride, was measured for each ROI. In all subjects of Group 1, SUVs after insertion were higher than before in both alveolar bone and residual bone, while there was less significant change in SUV in subjects of Group 2. This study demonstrated using longitudinal 18F-fluoride PET scans to effectively examine the bone metabolic change in mandible induced by occlusal loading after RPD insertion. Using this technique, within the six subjects in this study, it was shown that bone metabolism around abutment tooth and residual ridge increased after RPD insertion in case of first-time denture user, while there was no big change in the patient with experience of denture before. This study revealed the effectiveness of applying PET to evaluate bone metabolic activity as mechanobiolo-gical reaction. PMID:26431672

  19. The Conometric Concept: Coupling Connection for Immediately Loaded Titanium-Reinforced Provisional Fixed Partial Dentures-A Case Series.

    PubMed

    Degidi, Marco; Nardi, Diego; Piattelli, Adriano

    2016-01-01

    The aim of this prospective study was to demonstrate the feasibility of the conic coupling connection as a novel approach for the retention of immediately loaded, titanium-reinforced, temporary fixed partial restorations. The patients received a fixed, immediate partial restoration, attached using the conic coupling connection to two implants placed in a fresh extraction socket. Changes in marginal peri-implant bone level or probing depth measurements, biologic or technical complications, and any other adverse event were recorded at yearly follow-ups up to 3 years after implantation. A total of 78 implants placed in 39 patients reached the 3-year follow-up. A trend of bone overgrowth over the implant platform (mean: 0.2 mm) and a complete fill of the vertical gap between the implant platform level and the first point of contact of the bone with the implant surface was seen after the 6-month follow-up. No disconnection of any prosthesis was noted during 3 years of full occlusal function. The results of this study suggest that titanium-reinforced, temporary partial restorations with conic coupling retention supported by immediate implants provide a successful, cost-effective treatment modality. PMID:27100804

  20. Success, clinical performance and patient satisfaction of direct fibre-reinforced composite fixed partial dentures - a two-year clinical study.

    PubMed

    Malmstrom, H; Dellanzo-Savu, A; Xiao, J; Feng, C; Jabeen, A; Romero, M; Huang, J; Ren, Y; Yunker, M A

    2015-12-01

    To evaluate the success, clinical performance and patient satisfaction of directly placed fibre-reinforced composite (FRC) fixed partial dentures (FPDs) in 2 years. One hundred sixty-seven FRC FPDs (120 subjects) were directly fabricated to restore a single missing tooth by six Advanced Education in General Dentistry (AEGD) residents. The FRC FPDs recipients were randomised into two groups according to the fibre materials (pre-impregnated glass or polyethylene). Clinical performance was evaluated at baseline (2 weeks), 6, 12 and 24 months by two calibrated evaluators for prosthesis adaptation, colour match, marginal discoloration, surface roughness, caries and post-operative sensitivity using modified United State Public Health Service (USPHS) criteria. Prosthesis appearance, colour, chewing ability and overall satisfaction were evaluated by patients using a visual analogue scale (VAS). Kaplan-Meier estimation was used to estimate the prosthesis success. Ninety-four patients with 137 FRC FPDs returned (21·67% attrition rate for study subjects, 17·94% for FRC FPDs). Seventeen FRC FPDs failed, due to one-end (n = 4) or two-ends (n = 4) debonding or pontic fracture (n = 9). The cumulative 2-year success rate was 84·32% and survival rate was 92·7%; there were no statistically significant differences between the groups according to different missing tooth location, retention type or fibre materials (P > 0·05). Patient satisfaction regarding prosthesis appearance, col-our, chewing ability and overall satisfaction was rated high on the VAS (mean >80 mm) for all criteria at all time points. The FRC FPDs (restoring single tooth) fabricated by AEGD residents achieved acceptable success and survival rates in a 2-year follow-up. PMID:26172283

  1. Meta-analysis of Failure and Survival Rate of Implant-supported Single Crowns, Fixed Partial Denture, and Implant Tooth-supported Prostheses

    PubMed Central

    Muddugangadhar, B C; Amarnath, G S; Sonika, Radhika; Chheda, Pratik S; Garg, Ashu

    2015-01-01

    Background: Dental implants have become the most viable option for rehabilitation. Although, many studies report the success of these reconstructions using implants, a cumulative data about the various studies and the failure rate still remain unaddressed. Therefore, the purpose of this systematic review was to analyze these data and to derive the cumulative survival rate of different implant-supported prosthesis. Materials and Methods: Manual searches followed by a MEDLINE search were conducted to select prospective and retrospective cohort studies on single crowns (SCs), fixed partial denture (FPD), and tooth implant connected prostheses with a mean follow-up time of minimum of 5 years. Random-effects Poisson’s regression models have been used to obtain summary estimates for implant failure and survival rates. Results: Data were extracted from the final selected 63 studies. In a meta-analysis of these studies, the survival rate of SCs supported by implants (95% CI) was 96.363%, for FPDs was 94.525% and implant tooth-supported prostheses was 91.27% after 5 years of function. The cumulative failure rate per 100 FPD years of the SCs, FPDs, and implant tooth-supported prostheses were 0.684, 0.881, and 1.514, respectively. Conclusion: The study concludes high survival rates for implant-supported SCs followed by implant-supported FPDs can be expected over an observation period of 5 years. However, tooth implant-supported prostheses can be provided if there are certain limitations prohibiting the completely implant-supported prostheses. PMID:26435609

  2. Comparison of fiber reinforcement placed at different locations of pontic in interim fixed partial denture to prevent fracture: An in vitro study

    PubMed Central

    Kapri, Surg Cdr Anita

    2015-01-01

    Background: The interim restoration is an important phase in fixed prosthodontic therapy. It should provide sufficient durability to withstand the forces of mastication. A fractured interim restoration is damaging to the prosthodontic care and may lead to an unscheduled appointment for repair. Several attempts have been made to reinforce interim fixed partial dentures (FPDs). These have included the use of metal wire, a lingual cast metal reinforcement, a processed acrylic resin interim restoration, and different types of fibers, e.g., carbon, polyethylene, nylon and glass. These fibers can be placed in the occlusal, middle or cervical thirds in the FPD. There is no scientific data to evaluate the effect of fiber placement methods on the fracture resistance of clinical interim FPDs. Purpose of the Study: Hence this study was designed to evaluate fracture load values of interim FPDs with different locations of fiber reinforcement. Materials and Methods: 30 interim FPD samples with polymethyl methacrylate (PMMA) reinforced with fibers at three different locations mainly occlusal, cervical and middle (10 samples each) were fabricated using a metal FPD on a master die. They were tested for fracture resistance in universal testing machine. Results: The fracture resistance was recorded and is tabulated and analyzed statistically. The results showed that the placement of the reinforcement in the occlusal third of the pontic resulted in higher fracture resistance which was significantly higher (P < 0.05) than all other locations. Conclusion: The occlusal third of the pontic region from mesial to the distal end of the connector is the best site of placement of the fiber for reinforcing the PMMA interim restorative resin. PMID:26929501

  3. Improved Prefrontal Activity and Chewing Performance as Function of Wearing Denture in Partially Edentulous Elderly Individuals: Functional Near-Infrared Spectroscopy Study.

    PubMed

    Kamiya, Kazunobu; Narita, Noriyuki; Iwaki, Sunao

    2016-01-01

    The purpose of this study was to elucidate the effects of wearing a denture on prefrontal activity during chewing performance. We specifically examined that activity in 12 elderly edentulous subjects [63.1±6.1 years old (mean ± SD)] and 12 young healthy controls (22.1±2.3 years old) using functional near-infrared spectroscopy (fNIRS) in order to evaluate the quality of prefrontal functionality during chewing performance under the conditions of wearing a denture and tooth loss, and then compared the findings with those of young healthy controls. fNIRS and electromyography were used simultaneously to detect prefrontal and masticatory muscle activities during chewing, while occlusal force and masticatory score were also examined by use of a food intake questionnaire. A significant increase in prefrontal activity was observed during chewing while wearing a denture, which was accompanied by increased masticatory muscle activity, occlusal force, and masticatory score, as compared with the tooth loss condition. Prefrontal activation during chewing while wearing a denture in the elderly subjects was not much different from that in the young controls. In contrast, tooth loss in the elderly group resulted in marked prefrontal deactivation, accompanied by decreased masticatory muscle activity, occlusal force, and masticatory score, as compared with the young controls. We concluded that intrinsic prefrontal activation during chewing with a denture may prevent prefrontal depression induced by tooth loss in elderly edentulous patients. PMID:27362255

  4. Improved Prefrontal Activity and Chewing Performance as Function of Wearing Denture in Partially Edentulous Elderly Individuals: Functional Near-Infrared Spectroscopy Study

    PubMed Central

    Kamiya, Kazunobu; Narita, Noriyuki; Iwaki, Sunao

    2016-01-01

    The purpose of this study was to elucidate the effects of wearing a denture on prefrontal activity during chewing performance. We specifically examined that activity in 12 elderly edentulous subjects [63.1±6.1 years old (mean ± SD)] and 12 young healthy controls (22.1±2.3 years old) using functional near-infrared spectroscopy (fNIRS) in order to evaluate the quality of prefrontal functionality during chewing performance under the conditions of wearing a denture and tooth loss, and then compared the findings with those of young healthy controls. fNIRS and electromyography were used simultaneously to detect prefrontal and masticatory muscle activities during chewing, while occlusal force and masticatory score were also examined by use of a food intake questionnaire. A significant increase in prefrontal activity was observed during chewing while wearing a denture, which was accompanied by increased masticatory muscle activity, occlusal force, and masticatory score, as compared with the tooth loss condition. Prefrontal activation during chewing while wearing a denture in the elderly subjects was not much different from that in the young controls. In contrast, tooth loss in the elderly group resulted in marked prefrontal deactivation, accompanied by decreased masticatory muscle activity, occlusal force, and masticatory score, as compared with the young controls. We concluded that intrinsic prefrontal activation during chewing with a denture may prevent prefrontal depression induced by tooth loss in elderly edentulous patients. PMID:27362255

  5. Reducing the risk of sensitivity and pulpal complications after the placement of crowns and fixed partial dentures.

    PubMed

    Brännström, M

    1996-10-01

    Sensitivity after cementation of a crown with glass-ionomer cement is often attributed to an adverse effect on the pulp by the luting agent. Most permanent restorative materials in common use today do not tend to irritate the pulp; the main cause of pulpal damage is infection, the bacteria originating in the smear layer or deep in the dental tubules, inaccessible to caries-excavating procedures. A poorly fitting provisional crown may expose cut dentin to the oral fluids, and mechanical trauma caused by frictional heat during preparation may also damage the pulp. The following precautions are recommended during precementation procedures to reduce the risk of an inflammatory response in the pulp: (1) The provisional crown should be well fitting, covering cervical dentin but not impinging on the periodontal tissues. The permanent crown should be cemented as soon as possible. (2) The superficial smear layer should be removed and the dentinal surface should be treated with an antibacterial solution before the provisional crown is placed. (3) To decrease dentinal permeability under the provisional crown, the dentinal surface should be covered with a liner that can be easily removed before final cementation. (4) to ensure optimal mircomechanical bonding, the dentinal surface should be thoroughly cleaned, and the dentin should be kept moist until cementation. (5) The occlusion should be carefully checked before cementation of the crown. PMID:9180403

  6. 21 CFR 872.3520 - OTC denture cleanser.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3520 OTC denture cleanser. (a) Identification. An... that is intended to remove debris from removable prosthetic dental appliances, such as bridges...

  7. 21 CFR 872.3520 - OTC denture cleanser.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3520 OTC denture cleanser. (a) Identification. An... that is intended to remove debris from removable prosthetic dental appliances, such as bridges...

  8. 21 CFR 872.3520 - OTC denture cleanser.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3520 OTC denture cleanser. (a) Identification. An... that is intended to remove debris from removable prosthetic dental appliances, such as bridges...

  9. 21 CFR 872.3520 - OTC denture cleanser.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3520 OTC denture cleanser. (a) Identification. An... that is intended to remove debris from removable prosthetic dental appliances, such as bridges...

  10. Utilization of Partially Gasified Coal for Mercury Removal

    SciTech Connect

    Chris Samuelson; Peter Maly; David Moyeda

    2008-09-09

    In this project, General Electric Energy and Environmental Research Corporation (EER) developed a novel mercury (Hg) control technology in which the sorbent for gas-phase Hg removal is produced from coal in a gasification process in-situ at a coal burning plant. The main objective of this project was to obtain technical information necessary for moving the technology from pilot-scale testing to a full-scale demonstration. A pilot-scale gasifier was used to generate sorbents from both bituminous and subbituminous coals. Once the conditions for optimizing sorbent surface area were identified, sorbents with the highest surface area were tested in a pilot-scale combustion tunnel for their effectiveness in removing Hg from coal-based flue gas. It was determined that the highest surface area sorbents generated from the gasifier process ({approx}600 m{sup 2}/g) had about 70%-85% of the reactivity of activated carbon at the same injection rate (lb/ACF), but were effective in removing 70% mercury at injection rates about 50% higher than that of commercially available activated carbon. In addition, mercury removal rates of up to 95% were demonstrated at higher sorbent injection rates. Overall, the results of the pilot-scale tests achieved the program goals, which were to achieve at least 70% Hg removal from baseline emissions levels at 25% or less of the cost of activated carbon injection.

  11. Bioretention Systems: Partial Factorial Designs for Nitrate Removal

    EPA Science Inventory

    Changes in nutrient loadings are monitored by introducing captured stormwater runoff into eight outdoor rain gardens at EPA’s Urban Water Research Facility in Edison, New Jersey scaled for residential and urban landscapes. The partial factorial design includes non-vegetated meso...

  12. A clinical diagnosis of diurnal (non-sleep) bruxism in denture wearers.

    PubMed

    Piquero, K; Sakurai, K

    2000-06-01

    The purpose of this study was to establish a clinical method for diagnosing diurnal bruxism in denture wearers by recording masseter and anterior temporal electromyograph (EMG) activity. Seven suspected bruxists and five normal patients who wore complete dentures and/or distal extension base removable partial dentures were selected for participation. EMG activity in both the masseter and the anterior temporal muscles was recorded bilaterally during silent reading (10 min), maximal voluntary clenching (MVC), tapping in centric occlusion, lateral movements, chewing and swallowing. No significant differences of EMG activity were found between the groups during tapping, lateral movement, chewing and swallowing (P> 0.05). However, during 10 min of silent reading, a significant difference was found between the groups when comparing masseter muscle activity (P < 0.05). A threshold of 10% of MVC of at least 3-s duration was used to define an individual bruxism event. When the muscle activity recorded during silent reading was further analysed using these criteria, the control group displayed no bruxing activity while the suspected bruxist group displayed a mean frequency of six bruxism events (range 2-10). It was concluded that: (a) masseter muscle activity recorded during 10 min of silent reading showed significant difference between the groups; (b) the criteria selected in this study for the detection of sleep bruxism can also be used to assess diurnal bruxism; and (c) it is possible to diagnose diurnal bruxism in denture wearers by measuring the masseter EMG activity during 10 min of silent reading. PMID:10888274

  13. 30 CFR 250.1730 - When might MMS approve partial structure removal or toppling in place?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... partial structure removal or toppling in place for conversion to an artificial reef if you meet the following conditions: (a) The structure becomes part of a State artificial reef program, and the...

  14. Microcystic ganglioglioma treated by partial removal and radiation therapy

    SciTech Connect

    Cox, J.D.; Zimmerman, H.M.; Haughton, V.M.

    1982-08-01

    A 35-year old woman presented with visual hyperacuity and seizures. Radionuclide and CT scans revealed a frontal lobe mass lesion consistent with an astrocytoma. Subtotal removal was necessary due to proximity of the tumor to the motor strip. Initial histopathologic interpretation was malignant glioma (astrocytoma Grade 2 or 3). Megavoltage irradiation was delivered to a midsagittal dose of 6300 rad in seven weeks. Subsequent review of the slides revealed the tumor to be a microcystic ganglioglioma. The patient is well five and one-half years after treatment. It is important to separate these low grade neoplasms from the more ominous astrocytomas in regard to prognosis after resection and irradiation.

  15. Trial of an experimental castor oil solution for cleaning dentures.

    PubMed

    Andrade, Ingrid Machado de; Andrade, Kelly Machado de; Pisani, Marina Xavier; Silva-Lovato, Cláudia Helena; de Souza, Raphael Freitas; Paranhos, Helena de Freitas Oliveira

    2014-01-01

    Denture hygiene is essential because denture biofilm is involved in oral infections and systemic diseases. Although there are chemical agents available on the market, none of them have ideal properties and research on such products is still necessary. The aim of this study was to evaluate the efficacy of a castor bean (Ricinus communis)-based solution for removing denture biofilm, compared to two traditional products (sodium hypochlorite and alkaline peroxide). Fifty maxillary complete denture wearers were instructed to brush their dentures after meals and to immerse their dentures once a day in the following solutions: Saline (20 min; control), Polident alkaline peroxide (3 min), NaOCl (20 min) and 2% castor oil solution (20 min). Participants used each solution for a period of 7 consecutive days, according to a random sequence. After each period, the internal surfaces of maxillary complete dentures were stained with a disclosing solution (1% neutral red), photographed and the disclosed biofilm was quantified with the aid of specific software. The influence of treatments on results was verified by the Friedman test (α=0.05). Tested solutions presented significant difference (Fr=51.67; p<0.001). Saline and NaOCl were significantly different (median: 2.0% and 0.0%) whereas Polident and castor oil presented intermediate results (median: 1.0% and 1.5%, respectively). It can be concluded that the castor oil solution tested in this study was comparable to alkaline peroxide in terms of efficiency in denture biofilm removal. PMID:24789291

  16. The removal of partially metabolized very-low-density lipoproteins by the perfused rat liver.

    PubMed Central

    Suri, B S; Targ, M E; Robinson, D S

    1981-01-01

    1. Donor perfused rat livers were used to prepare VLD (very-low-density) lipoproteins, labelled in their triacylglycerol and protein components with [1-14C]oleic acid and L-[4,5-3H]leucine respectively. Partially metabolized VLD lipoproteins, similarly labelled, were obtained from supradiaphragmatic rats injected with the parent VLD lipoproteins. 2. The triacylglycerol and protein components of the partially metabolized VLD lipoproteins were removed by recipient perfused rat livers at rates much higher than those of the parent VLD lipoproteins. No degradation of the partially metabolized VLD lipoproteins to LD (low-density) lipoproteins occurred during the perfusions. 3. Removal of hepatic lipase from the livers did not significantly affect the rate of removal of the partially metabolized VLD lipoproteins. PMID:7317016

  17. Cast aluminum denture base.

    PubMed

    Barco, M T; Dembert, M L

    1987-08-01

    The laboratory procedures for a cast aluminum base denture have been presented. If an induction casting machine is not available, the "two-oven technique" works well, provided the casting arm is kept spinning manually for 4 minutes after casting. If laboratory procedures are executed precisely and with care, the aluminum base denture can be cast with good results. PMID:3305884

  18. Esophageal impacted dentures.

    PubMed Central

    Nwaorgu, Onyekwere G.; Onakoya, Paul A.; Sogebi, Olusola A.; Kokong, Daniel D.; Dosumu, Oluwole O.

    2004-01-01

    OBJECTIVES: This study aims to highlight the problems associated with impacted acrylic dentures and proffers advice to check them. PATIENTS AND METHODS: Retrospective review of all cases of impacted acrylic dentures over a 16-year period. RESULTS: Twenty-two adults had impacted esophageal acrylic dentures of which 16 (72.7%) and six (27.3%) were males and females, respectively (M:F ratio = 2.7:1) with age range 23-77 years. Fourteen patients (63.6%) had worn their dentures for more than 10 years without check-up, and 54.5% presented within 48 hours of impaction. The common symptoms in all the patients were difficulty with swallowing, throat pain and discomfort, followed by tenderness in the neck in 15 (68.2%). Dentures were extracted through esophagoscopy (17 cases) and cervical (three cases) esophagotomy, respectively. Observed complications included pulmonary edema in one and esophageal perforation in five patients. CONCLUSION: Endoscopic extraction of dentures carries a high risk of perforation. Extraction of an impacted denture via esophagoscopy can be undertaken under direct vision and in an ideal situation with judicious use of the Shears forceps. In the absence of these, the safest option is an esophagotomy. Proper treatment planning in the fabrication of dentures with incorporation of radiopaque materials in the dental resins and adequate postdenture delivery instructions are necessary as preventive measures. PMID:15540888

  19. Prosthetic rehabilitation of a patient after a partial mandibulectomy

    PubMed Central

    Goiato, Marcelo Coelho; de Medeiros, Rodrigo Antonio; Vechiato Filho, Aljomar José; da Silva, Emily Vivianne Freitas; Sônego, Mariana Vilela; de Carvalho, Karina Helga Turcio; Guiotti, Aimée Maria; de Carvalho Dekon, Stefan Fiuza; Pesqueira, Aldiéris Alves; dos Santos, Daniela Micheline

    2015-01-01

    Introduction The treatment of orofacial tumors may cause facial deformities by losses of structures that affect basic functions, i.e. feeding, speech, and the reduction of patient self-steam. Presentation of case A white male patient was diagnosed with epidermoid cancer on the mandibular alveolar ridge with infiltration staging IV A. The patient was submitted to a mandibulectomy associated with a complete extraction of mandibular teeth. For rehabilitation, a conventional denture for the mandibular arch and a removable partial denture for the maxillary arch were fabricated. A correct occlusal adjustment and a satisfactory amount of alveolar bone was favorable for conventional dentures of the prostheses bases improve their retention and stability. After one year of follow-up, the patient was adapted to the prostheses, satisfied with their retention, and reported an improvement on his feeding. Discussion The prosthetic rehabilitation of patients after a partial mandibulectomy is essential for their self-steam. Conventional dentures may have their retention and stability improved if they are well fabricated, recorded and have a balanced occlusion. Conclusion A correct occlusal adjustment and an adequate retention of the prostheses bases may improve their retention and stability. Patients without xerostomy and with a satisfactory amount of alveolar bone may have a favorable prognosis for conventional dentures. PMID:26052437

  20. [Effect of HCO3- on Nitrogen Removal Efficiency in Partial Nitritation-ANAMMOX Process].

    PubMed

    Li, Xiang; Cheng, Zong-heng; Huang, Yong; Yuan, Yi; Liu, Xin; Zhang, Da-lin

    2015-11-01

    The effect of HCO3- on nitrogen removal efficiency in partial nitritation-ANAMMOX process was studied by using the combined process of partial nitritation and ANAMMOX has been started and achieved the stable operation of nitrogen removal. The results showed that, when the ratio of C/N decreased from 2 to 0.17 in influent, the nitrogen removal rate decreased from 1.3 kg- ( M3 x d)(-1) to 0.40 kg x (M3 x d)(-1), the decrease range arrived at 69.3%. The nitrogen conversion efficiency was limited, because of the added amount of HCO3- was decreased, which leading to the pH value declined sharply in nitritation and ANAMMOX zone. In the partial nitritation-ANAMMOX process, the effect of HCO3- limitation on activity of ammonium oxidizing bacteria, ANAMMOX bacteria and nitrifying bacteria was decreased in turn. When the C/N ratio increased to 1, the nitrogen removal rate of combined process was quickly restored to 1 kg x (m3 x d)(-1). It indicated that short HCO3- limitation on nitrogen conversion efficiency of the combined process can be fast recovery. The resulted also showed that the relationship between influent C/N ratio and nitrogen removal efficiency has obvious relativity in partial nitritation-ANAMMOX process. PMID:26911008

  1. Designing for Safety: Implications of a Fifteen Year Review of Swallowed and Aspirated Dentures

    PubMed Central

    Mackie, James; Macfarlane, Tatiana V.

    2016-01-01

    ABSTRACT Objectives Dentures are worn by around 20% of the population, yet if they become displaced they may enter the gastrointestinal or respiratory system, sometimes with grave consequences. The aim of this study was to review recent published literature in order to identify the epidemiology of patients and characteristics of swallowed and aspirated dental prostheses, and propose strategies to minimise these risks. Material and Methods A fifteen year retrospective of published case series and case reports was carried out. Photographs, radiographs and descriptions of the dental prostheses were gathered, as well as the patient’s presenting complaint, the anatomical site where the denture was caught and the procedure required to remove the denture. Results Ninety one separate events of swallowed or aspirated dentures were identified from 83 case reports and series from 28 countries. Average age was 55 years, and these were 74% male. Photographs were retrieved for 49 of these dentures. Clasps were present in 25 of the dentures. There was no significant difference between clasped and unclasped dentures for perforation rates, need for open surgery and spontaneously passed dentures. Conclusions We discuss the implications of this study regarding denture designs, specifically the importance of using a radiopaque acrylic, using clasps when required even if there is a risk of aspiration, advising patients to return if a denture is loose or damaged, and finally that all patients who wear a denture are at risk of aspiration and swallowing events, and associated morbidity and mortality. PMID:27489607

  2. EFFICACY OF BIOFILM DISCLOSING AGENT AND OF THREE BRUSHES IN THE CONTROL OF COMPLETE DENTURE CLEANSING

    PubMed Central

    da Silva, Cláudia Helena Lovato; Paranhos, Helena de Freitas Oliveira

    2006-01-01

    Objective: This report evaluated the efficacy of three brushes and one biofilm disclosing agent in complete denture cleansing. Methods: Twenty-seven wearers of maxillary dentures were distributed into three groups and received different brushes: Oral B40, conventional toothbrush (Oral B); Denture, denture-specific brush (Condor); Johnson & Johnson, denture-specific brush (Johnson & Johnson). The 60-day experimental period was divided into two techniques: I - brushing (brush associated with a paste - Dentu Creme, Dentco) three times a day; II - brushing and daily application of 1% neutral red on the denture internal surface. Biofilm quantification was carried out weekly and the areas with dye biofilm were obtained by means of Image Tool 2.02 software. Results: Biofilm removal was more effective during Technique II (Wilcoxon test: p=0.01) for the three groups of brushes. When the brushes were compared in Technique I, the Kruskal Wallis test indicated statistical difference between Denture X Johnson & Johnson and Denture X Oral B40, in which the Denture was more efficient. For Technique II, there was no statistical difference between brushes (p>0.05). Conclusion: The disclosed application promoted more efficacy on biofilm removal, regardless of the brush used. Denture (Condor) was more efficient than the other brushes during Technique I. PMID:19089247

  3. Impact of denture usage patterns on dietary quality and food avoidance among older adults.

    PubMed

    Savoca, Margaret R; Arcury, Thomas A; Leng, Xiaoyan; Chen, Haiying; Bell, Ronny A; Anderson, Andrea M; Kohrman, Teresa; Gilbert, Gregg H; Quandt, Sara A

    2011-01-01

    This study categorizes older adults living in rural areas by denture status, assesses the frequency of wearing dentures during meals, and determines whether denture status or use is associated with dietary quality or the number of foods avoided. A multi-ethnic population-based sample of adults ≥60 years (N = 635) in the rural United States was interviewed. Survey included denture use, removing dentures before eating, and foods avoided due to oral health problems. Dietary intakes were converted into Healthy Eating Index-2005 scores. Sixty percent wore removable dentures of some type; 55% never, 27% sometimes, and 18% always removed dentures when eating. More frequent removal was associated with lower dietary quality and more foods avoided. Those with severe tooth loss had the lowest dietary quality and avoided the most foods. Many rural older adults wear dentures. Learning how they adapt to denture use will offer insight into their nutritional self-management and help explain differences in dietary quality. PMID:23286643

  4. Partial Nitrification and Denitrifying Phosphorus Removal in a Pilot-Scale ABR/MBR Combined Process.

    PubMed

    Wu, Peng; Xu, Lezhong; Wang, Jianfang; Huang, Zhenxing; Zhang, Jiachao; Shen, Yaoliang

    2015-11-01

    A pilot-scale combined process consisting of an anaerobic baffled reactor (ABR) and an aerobic membrane bioreactor (MBR) for the purpose of achieving easy management, low energy demands, and high efficiencies on nutrient removal from municipal wastewater was investigated. The process operated at room temperature with hydraulic retention time (HRT) of 7.5 h, recycle ratio 1 of 200%, recycle ratio 2 of 100%, and dissolved oxygen (DO) of 1 mg/L and achieved good effluent quality with chemical oxygen demand (COD) of 25 mg/L, NH4 (+)-N of 4 mg/L, total nitrogen (TN) of 11 mg/L, and total phosphorus (TP) of 0.7 mg/L. The MBR achieved partial nitrification, and NO2 (-)-N has been accumulated (4 mg/L). Efficient short-cut denitrification was occurred in the ABR with a TN removal efficiency of 51%, while the role of denitrification and phosphorus removal removed partial TN (14%). Furthermore, nitrogen was further removed (11%) by simultaneous nitrification and denitrification in the MBR. In addition, phosphorus accumulating organisms in the MBR sufficiently uptake phosphorus; thus, effluent TP further reduced with a TP removal efficiency of 84%. Analysis of fluorescence in situ hybridization (FISH) showed that ammonia oxidizing bacteria (AOB) and phosphorus accumulating organisms (PAOs) were enriched in the process. In addition, the accumulation of NO2 (-)-N was contributed to the inhibition on the activities of the NOB rather than its elimination. PMID:26411352

  5. Evidence Regarding the Treatment of Denture Stomatitis.

    PubMed

    Yarborough, Alexandra; Cooper, Lyndon; Duqum, Ibrahim; Mendonça, Gustavo; McGraw, Kathleen; Stoner, Lisa

    2016-06-01

    Denture stomatitis is a common inflammatory condition affecting the mucosa underlying complete dentures. It is associated with denture microbial biofilm, poor denture hygiene, poor denture quality, and nocturnal denture use. Numerous treatment methodologies have been used to treat stomatitis; however, a gold standard treatment has not been identified. The aim of this systematic review is to report on the current knowledge available in studies representing a range of evidence on the treatment of denture stomatitis. PMID:27062660

  6. Effect of surface treatments on shear bond strength of denture teeth to denture base resins

    PubMed Central

    Bahrani, Farideh; Khaledi, Amir Ali Reza

    2014-01-01

    Background: Debonding of denture teeth from denture bases is the most common failure in removable dentures. The purpose of this study was to evaluate the effect of surface treatments on shear bond strength of denture teeth to heat-polymerized and autopolymerized denture base resins. Materials and Methods: In this experimental in vitro study, 60 maxillary central incisor acrylic teeth were divided into two groups. Group M was polymerized with heat-polymerized acrylic resin (Meliodent) by compression molding technique and group F was processed by autopolymerized acrylic resin (Futura Gen) by injection molding technique. Within each group, specimens were divided into three subgroups according to the teeth surface treatments (n = 10): (1) ground surface as the control group (M1 and F1), (2) ground surface combined with monomer application (M2 and F2), and (3) airborne particle abrasion by 50 μm Al2O3 (M3 and F3). The shear bond strengths of the specimens were tested by universal testing machine with crosshead speed of 5 mm/min. Data were analyzed by two-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) tests (P < 0.05). Results: The mean shear bond strengths of the studied groups were 96.40 ± 14.01, 124.70 ± 15.64, and 118 ± 16.38 N for M1, M2, and M3 and 87.90 ± 13.48, 117 ± 13.88, and 109.70 ± 13.78 N for F1, F2, and F3, respectively. The surface treatment of the denture teeth significantly affected their shear bond strengths to the both the denture base resins (P < 0.001). However, there were no significant differences between the groups treated by monomer or airborne particle abrasion (P = 0.29). The highest percentage of failure mode was mixed in Meliodent and adhesive in Futura Gen. Conclusion: Monomer application and airborne particle abrasion of the ridge lap area of the denture teeth improved their shear bond strengths to the denture base resins regardless of the type of polymerization. PMID:24688570

  7. Sectional impression tray and sectional denture for a microstomia patient.

    PubMed

    Colvenkar, Shreya S

    2010-02-01

    Microstomia presents a unique challenge to the patient. Patients with microstomia who must wear removable dental prostheses often face the difficulty of being unable to insert or remove the prosthesis because of the constricted opening of the oral cavity. A completely edentulous patient, who developed microstomia along with Raynaud's phenomenon induced by scleroderma, is presented. This clinical report describes a quick and easy method for fabrication of a sectional custom impression tray connected by press button and a sectional complete denture retained by magnets. A sectional denture that provides ease in placement and removal can be successfully used in clinical practice for treatment of microstomia patients. PMID:19895427

  8. Reductions in contaminant mass discharge following partial mass removal from DNAPL source zones.

    PubMed

    Suchomel, Eric J; Pennell, Kurt D

    2006-10-01

    Although in situ remediation technologies have been used to aggressively treat dense nonaqueous phase liquid (DNAPL) source zones, complete contaminant removal or destruction is rarely achieved. To evaluate the effects of partial source zone mass removal on dissolved-phase contaminant flux, four experiments were conducted in a two-dimensional aquifer cell that contained a tetrachloroethene (PCE) source zone and down-gradient plume region. Initial source zone PCE saturation distributions, quantified using a light transmission system, were expressed in terms of a ganglia-to-pool ratio (GTP), which ranged from 0.16 (13.8% ganglia) to 1.6 (61.5% ganglia). The cells were flushed sequentially with a 4% (wt.) Tween 80 surfactant solution to achieve incremental PCE mass removal, followed by water flooding until steady-state mass discharge and plume concentrations were established. In all cases, the GTP ratio decreased with increasing mass removal, consistent with the observed preferential dissolution of PCE ganglia and persistence of high-saturation pools. In the ganglia-dominated system (GTP = 1.6), greater than 70% mass removal was required before measurable reductions in plume concentrations and mass discharge were observed. For pool-dominated source zones (GTP < 0.3), substantial reductions (>50%) in mass discharge were realized after only 50% mass removal. PMID:17051808

  9. In vitro fertilization rate of horse oocytes with partially removed zonae.

    PubMed

    Choi, Y H; Okada, Y; Hochi, S; Braun, J; Sato, K; Oguri, N

    1994-10-01

    Frozen-thawed ejaculated stallion spermatozoa were preincubated for 3 h in BO medium containing 5 mM caffeine and then treated with 0.1 micro M calcium ionophore A23187 for 60 sec. Aliquots of the sperm suspension (final concentration 1-2 x 10(7)/ml) were added to the oocytes which had been matured in vitro for 32 h. In Experiment 1, there were 3 groups of oocytes; cumulus intact, denuded zona-intact, and zona-free. Cumulus cells were removed with 0.5% hyaluronidase and the zona pellucida with 0.1% protease. The oocytes were fixed 20 h after insemination with acetic acid:ethanol (1:3) and stained with 1% orcein. The sperm penetration rate of zona-free oocytes was 83%, whereas the sperm penetration rate was very low (1 to 3%) in the cumulus-enclosed or zona-intact oocytes. In Experiment 2, denuded zona-intact oocytes were placed in PBS supplemented with 10% fetal bovine serum 1 h before the end of in vitro maturation. The zona pellucida was micromanipulated with a metal microblade under x 100 magnification within 20 min of treatment with 0.3 M sucrose. For partial zona dissection, a slit in the zona pellucida was made. For partial zona removal, oocytes were transferred to protein-free PBS to fix the oocytes on the bottom of the Petri-dish and to remove a piece of the zona pellucida. Micromanipulated oocytes were subjected to in vitro fertilization as described above. Zona-intact and zona-free oocytes treated with sucrose solution for 20 min were used as controls. The penetration rates were 4 (2/57), 12 (7/58), 52 (31/60), and 86% (44/51) for zona-intact, partially zona dissected, partially zona removed, and zona-free oocytes, respectively. Proportions of oocytes with monospermic penetration were 100 (2/2), 57 (4/7), 58 (18/31), and 34% (15/44), respectively. In Experiment 3, sperm penetration and male pronucleus formation in the partially zona removed oocytes were examined at 2.5 to 20.0 h of insemination. Sperm penetration started 2.5 h post-insemination (22%, 11

  10. ANAMMOX and partial denitritation in anaerobic nitrogen removal from piggery waste.

    PubMed

    Ahn, Y H; Hwang, I S; Min, K S

    2004-01-01

    The anaerobic ammonium removal from a piggery waste with high strength (56 g COD/L and 5 g T-N/L) was investigated using a lab-scale upflow anaerobic sludge bed reactor at a mesophilic condition. Based on the nitrogen and carbon balance in the process, the contribution of autotrophic and heterotrophic organisms was also evaluated in terms of the influent NO2-N/NH4-N ratio (1:0.8 and 1:1.2 for Phase 1 and Phase 2, respectively). The result of this research demonstrates that the anaerobic ammonium removal from the piggery waste, using the UASB reactor, can be performed successfully. Furthermore, it appears that by using granular sludge as the seed biomass, the ANAMMOX reaction can start more quickly. Average nitrogen conversion was 0.59 kg T-N/m3 reactor-day (0.06 kg T-N/kg VSS/day) and 0.66 kg T-N/m3 reactor-day (0.08 kg T-N/kg VSS/day) for Phase 1 and Phase 2. The NO2-N/NH4-N removal ratio by the ANAMMOX was 1.48 and 1.79 for Phase 1 and Phase 2. The higher nitrite contents (about 50%) in the substrate resulted in higher nitrite nitrogen removal by the partial denitritation, as well as the ANAMMOX reaction, implying higher potential of partial denitritation. However, the result reveals that the ANAMMOX reaction was influenced less by the degree of partial denitritation, and the ANAMMOX bacteria did not compete with denitritation bacteria. The colour of the biomass at the bottom of the reactor changed from dark gray to dark red, which was accompanied by an increase in cytochrome content. At the end of the experiment, red-coloured granular sludge with diameter of 1-2 mm at the lower part of the reactor was also observed. PMID:15137418

  11. Microbiological analysis after complete or partial removal of carious dentin in primary teeth: a randomized clinical trial.

    PubMed

    Lula, E C O; Monteiro-Neto, V; Alves, C M C; Ribeiro, C C C

    2009-01-01

    Since viable bacteria can persist in tooth cavities regardless of the technique used for caries removal, the objective of the present randomized clinical trial was to examine the microflora of primary teeth treated by complete or partial removal of carious dentin. Deciduous molars with acute carious lesions in the inner half of dentin and vital pulp were randomly divided into two groups of 16: complete removal, in which the carious dentin was completely removed with the help of a caries detector dye, and partial removal, in which the carious dentin was completely removed from the dentinoenamel junction and lateral walls, while the necrotic carious dentin from the cavity floor was only removed superficially. Dentin samples were obtained with a sterile No. 3 bur after caries removal and 3-6 months after protection with calcium hydroxide cement and restoration of the cavities with resin composite. The samples were stored in thioglycolate. Decimal dilutions were then prepared and seeded for the enumeration of Streptococcus spp., mutans streptococci, Lactobacillus spp. and total microorganisms. Before sealing, a larger number of microorganisms was detected in teeth submitted to partial caries removal compared to the complete removal group. However, after sealing the level of colonization was similar in the two groups for all microorganisms studied. The results suggest that persistence of bacteria does not seem to be a reason for reopening of cavities in deciduous teeth after partial caries removal. PMID:19648746

  12. Adjuvant antifungal therapy using tissue tolerable plasma on oral mucosa and removable dentures in oral candidiasis patients: a randomised double-blinded split-mouth pilot study.

    PubMed

    Preissner, Saskia; Kastner, Isabell; Schütte, Eyke; Hartwig, Stefan; Schmidt-Westhausen, Andrea Maria; Paris, Sebastian; Preissner, Robert; Hertel, Moritz

    2016-07-01

    Extended use of antimycotics in oral candidiasis therapy gives rise to problems related to fungal drug resistance. The aim of this pilot study was to investigate the efficacy of tissue tolerable plasma (TTP) in denture stomatitis patients. It was hypothesised that (I): erythema and (IIa): complaint remission would be accelerated and (IIb): colony forming unit (CFU) reduction would be improved. The halves of the upper jaws of eight patients were randomly assigned to control (nystatin, chlorhexidine and placebo treatment) and test sides (nystatin, chlorhexidine and TTP administered six times each 7 days). The patients and the investigators, who were different from the therapists, were both blinded. Compared to the control sides, the erythema surface was reduced significantly more extensively on the test sides between 2 and 6 weeks of antifungal therapy (P ≤ 0.05). Visual analogue scale values and the frequency of moderate or heavy growth of Candida post-treatment did not differ significantly between both sides (P > 0.05). The primary hypothesis was confirmed, which may be interpreted as an accelerated remission. As drug therapy is usually limited to the time in which signs of infection are present, TTP might help reducing antifungal use. Even though the secondary hypotheses were not confirmed, persistence of Candida might be only colonisation. PMID:26932256

  13. Partial caries removal in primary teeth: association of clinical parameters with microbiological status.

    PubMed

    Lula, E C O; Almeida, L J S; Alves, C M C; Monteiro-Neto, V; Ribeiro, C C C

    2011-01-01

    The relationship between clinical characteristics of carious dentin and bacterial colonization after partial caries removal is not completely understood. The aim of this study was to compare microbial counts between categories of carious dentin color, consistency and humidity, and to evaluate the correlation between these characteristics and the presence of cariogenic microorganisms in deep cavities (2/3 or more of the dentin thickness) submitted to partial caries removal. Sixteen primary teeth were submitted to the removal of all carious tissue from the lateral walls of the cavity, whereas carious tissue of the pulp wall was removed superficially. Dentin in the pulp wall was classified according to color, consistency and humidity immediately after cavity preparation and 3-6 months after cavity sealing and a tissue sample was collected on the same occasion for microbiological evaluation. Before sealing, Streptococcus mutans (p = 0.033) and Lactobacillus spp. (p = 0.048) counts were higher in cavities with humid dentin compared to cavities with dry dentin. A negative correlation was observed between carious dentin consistency and S. mutans count during this phase (r(s) = -0.571; p = 0.020). Arrest of dentinal caries lesions was observed after sealing, which was characterized by a reduction of bacterial counts and changes in dentin color, consistency and humidity, irrespectively of baseline dentin characteristics. The clinical characteristics of carious dentin change after the period of cavity sealing and cannot be applied as absolute indicators to limit the excavation of carious dentin when minimally invasive techniques are used. PMID:21576960

  14. The Use of Digital Impressions to Fabricate Tooth-Supported Partial Removable Dental Prostheses: A Clinical Report.

    PubMed

    Mansour, Mohamed; Sanchez, Eliana; Machado, Camilo

    2016-08-01

    Impression making is a critical step in the fabrication of a partial removable dental prosthesis (RDP). A technique is described for making final impressions to fabricate partial RDPs for Kennedy class III patients using a computer-aided design and computer-assisted manufacturing digital impression system. PMID:26371612

  15. Nitrogen removal from digested black water by one-stage partial nitritation and anammox.

    PubMed

    Vlaeminck, Siegfried E; Terada, Akihiko; Smets, Barth F; van der Linden, Davy; Boon, Nico; Verstraete, Willy; Carballa, Marta

    2009-07-01

    This study assessed the technical feasibility to treat digested black water from vacuum toilets (> 1000 mg NH4(+)-N L(-1)) in a lab-scale oxygen-limited autotrophic nitrification/denitrification (OLAND) rotating biological contactor. After an adaptation period of 2.5 months, a stable nitrogen removal rate of ca. 700 mg N L(-1) d(-1) was reached over the subsequent 5 months. Suppression of the nitrite oxidizing bacteria at free ammonia levels above 3 mg N L(-1) resulted in a nitrogen removal efficiency of 76%. The favorable ratios of both organic and inorganic carbon to nitrogen guaranteed endured anammox activity and sufficient buffering capacity, respectively. Quantitative FISH showed that aerobic and anoxic ammonium-oxidizing bacteria (AerAOB and AnAOB) made up 43 and 8% of the biofilm, respectively. Since a part of the AerAOB was probably present in anoxic biofilm zones; their specific ammonium conversion was very low, in contrast to the high specific AnAOB activity. DGGE analysis showed that the dominant AerAOB and AnAOB species were resistant to the transition from synthetic medium to digested black water. This study demonstrates high-rate nitrogen removal from digested black water by one-stage partial nitritation and anammox, which will allow a significant decrease in operational costs compared to conventional nitrification/ denitrification. PMID:19673303

  16. Part-Digitizing System of Impression and Interocclusal Record for Complete Denture Fabrication.

    PubMed

    Matsuda, Takashi; Goto, Takaharu; Yagi, Kazutomo; Kashiwabara, Toshiya; Ichikawa, Tetsuo

    2016-08-01

    Few studies have reported the application of digital technology to removable dentures, particularly for the process of impression and interocclusal recording for complete denture fabrication. This article describes a part-digitizing system of impression and interocclusal records for complete denture fabrication. The denture foundation area in an edentulous mouth, including the border areas and residual ridge, is outlined by tracing the surfaces with a 3-D pen-type digitizer. Specialized trays for final impressions and interocclusal records were generated using computer-aided design and manufactured using the digital data. Final impression and interocclusal records were carried out using these specialized trays. The computer-aided method using preliminary digital impressions and specialized trays would be feasible for clinical use for complete denture fabrication. PMID:26619371

  17. Clinical effect of photodynamic therapy on primary carious dentin after partial caries removal.

    PubMed

    Neves, Pierre Adriano Moreno; Lima, Leonardo Abrantes; Rodrigues, Fernanda Cristina Nogueira; Leitão, Tarcisio Jorge; Ribeiro, Cecília Cláudia Costa

    2016-05-20

    This study was conducted to assess the clinical effect of photodynamic therapy (PDT) in the decontamination of the deep dentin of deciduous molars submitted to partial removal of carious tissue. After cavity preparation, dentin samples were taken from the pulp wall of nineteen deciduous molars before and after PDT application. Remaining dentin was treated with 0.01% methylene blue dye followed by irradiation with an InGaAlP diode laser (λ - 660 nm; 40 mW; 120 J/cm2; 120 s). Dentin samples were microbiologically assessed for the enumeration of total microorganisms, Lactobacillus spp. and mutans streptococci. There was no significant difference in the number of colony-forming units (CFU) for any of the microorganisms assessed (p > 0.05). Photodynamic therapy, using 0.01% methylene blue dye at a dosimetry of 120 J/cm2 would not be a viable clinical alternative to reduce bacterial contamination in deep dentin. PMID:27223131

  18. [Biofilm disclosing agents in complete denture: clinical and antimicrobial evaluation].

    PubMed

    Silva, Cláudia Helena Lovato da; Paranhos, Helena de Freitas Oliveira; Ito, Isabel Yoko

    2002-01-01

    This study evaluated the disclosing ability, removal facility and antimicrobial effect of biofilm disclosing agents applied on complete dentures. Disclosing ability was evaluated by means of the visual method. The solutions were applied on the internal surface of dentures. After being photographed, the dentures were brushed with denture-specific brush and dentifrice and photographed again. The obtained slides were projected on paper (10 X amplification) and the total and stained surfaces were outlined with graphite, cut off and weighed, in order to assess removal facility. The evaluation of antimicrobial effects was carried out by means of the method of diffusion in agar, and the results were obtained by measuring the length of the halos and rings. In terms of disclosing ability, the best solutions were 0.05% methylene blue, 5% erythrosin, 1% sodic fluorescein, Replak and 1% neutral red. One percent eosin, 1% sodic fluorescein and 5% erythrosin were the most easily removed solutions. One percent eosin, 5% erythrosin, 1% sodic fluorescein, 0.3% proflavine, Replak and 1% neutral red presented no antimicrobial effect. The solutions which presented the greatest disclosing ability and removal facility as well as absence of antimicrobial effect - which are essential requirements in the assessment of hygiene methods and guidance on oral health - were 1% eosin, 1% neutral red and 5% erythrosin. PMID:12386691

  19. Impact of Denture Cleaning Method and Overnight Storage Condition on Denture Biofilm Mass and Composition: A Cross-Over Randomized Clinical Trial

    PubMed Central

    Duyck, Joke; Vandamme, Katleen; Krausch-Hofmann, Stefanie; Boon, Lies; De Keersmaecker, Katrien; Jalon, Eline; Teughels, Wim

    2016-01-01

    Background Appropriate oral hygiene is required to maintain oral health in denture wearers. This study aims to compare the role of denture cleaning methods in combination with overnight storage conditions on biofilm mass and composition on acrylic removable dentures. Methods In a cross-over randomized controlled trial in 13 older people, 4 conditions with 2 different mechanical cleaning methods and 2 overnight storage conditions were considered: (i) brushing and immersion in water without a cleansing tablet, (ii) brushing and immersion in water with a cleansing tablet, (iii) ultrasonic cleaning and immersion in water without a cleansing tablet, and (iv) ultrasonic cleaning and immersion in water with a cleansing tablet. Each test condition was performed for 5 consecutive days, preceded by a 2-days wash-out period. Biofilm samples were taken at baseline (control) and at the end of each test period from a standardized region. Total and individual levels of selected oral bacteria (n = 20), and of Candida albicans were identified using the Polymerase Chain Reaction (PCR) technique. Denture biofilm coverage was scored using an analogue denture plaque score. Paired t-tests and Wilcoxon-signed rank tests were used to compare the test conditions. The level of significance was set at α< 5%. Results Overnight denture storage in water with a cleansing tablet significantly reduced the total bacterial count (p<0.01). The difference in total bacterial level between the two mechanical cleaning methods was not statistically significant. No significant effect was observed on the amount of Candida albicans nor on the analogue plaque scores. Conclusions The use of cleansing tablets during overnight denture storage in addition to mechanical denture cleaning did not affect Candida albicans count, but reduced the total bacterial count on acrylic removable dentures compared to overnight storage in water. This effect was more pronounced when combined with ultrasonic cleaning compared to

  20. Analysis of the compressive strain below the removable and fixed prosthesis in the posterior mandible using a digital image correlation method.

    PubMed

    Tanasic, Ivan; Milic-Lemic, Aleksandra; Tihacek-Sojic, Ljiljana; Stancic, Ivica; Mitrovic, Nenad

    2012-07-01

    It was the purpose of this study to determine and analyse strains in the bone of posterior mandible below the removable and fixed partial dentures using Digital Image Correlation Method. Dried mandible with shortened dental arch (Kennedy Class 1) was used in the experiment. The mandible model was prepared for accepting two types of restorations for bilaterally missing molars conventional therapy, and removable and fixed partial dentures were manufactured following standard prosthetic protocol. The models with prosthetic restorations placed in situ were subjected to loading of 50-300 N, and photographed using two digital cameras as part of the digital image correlation method equipment. Afterwards, the obtained data for strains within restored mandible during loading ciclus were analysed in the software Aramis and graphically presented. Percentage size of the mandible strains within the line section are from 0.14 to 0.19% for the removable partial denture experimental model and 0-0.14% for the fixed partial denture experimental model. The study has demonstrated that Digital Image Correlation method can be used to measure strain on the mandible surface and replacements during loading and that from biomechanical perspective both therapeutic modalities can be equally useful for the restoration of the mandible with bilaterally distal edentulous spaces. PMID:21918835

  1. Randomized trial of partial vs. stepwise caries removal: 3-year follow-up.

    PubMed

    Maltz, M; Garcia, R; Jardim, J J; de Paula, L M; Yamaguti, P M; Moura, M S; Garcia, F; Nascimento, C; Oliveira, A; Mestrinho, H D

    2012-11-01

    This randomized, multicenter clinical trial evaluated the effectiveness of 2 treatments for deep caries lesions - partial caries removal (PCR) and stepwise excavation (SW) - with respect to the primary outcome of pulp vitality for a 3-year follow-up period. Inclusion criteria were as follows: patients with permanent molars presenting deep caries lesions (lesion affecting ≥ 1/2 of the dentin on radiographic examination), positive response to a cold test, absence of spontaneous pain, negative sensitivity to percussion, and absence of periapical lesions (radiographic examination). Teeth randomly assigned to PCR (test) received incomplete caries removal and filling in a single session. Outcome success was evaluated by assessment of pulp vitality, determined by pulp sensitivity to a cold test and the absence of periapical lesions. Data were analyzed by a Weibull regression model with shared frailty term (survival analysis). At baseline, 299 treatments were executed: PCR, 152 and SW, 147. By the end of the 3-year follow-up period, 213 teeth had been evaluated. Adjusted survival rates were 91% for PCR and 69% for SW (p = 0.004). These results suggest that there is no need to re-open a cavity and perform a second excavation for pulp vitality to be preserved (Clinical trials registration NCT00887952). PMID:22983407

  2. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 1: two example cases of a combined fixed-removable restoration].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    After a careful diagnosis, treatment planning and pretreatment, two partially edentulous patients were restored partly by onlays, crowns and bridges, partly by removable prostheses. According to esthetic and functional demands all- and/or metal-ceramic restorations were used as well as cast frame prostheses with clasps or extracoronal attachments. PMID:25735004

  3. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    NASA Astrophysics Data System (ADS)

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-06-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g‑1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L‑1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg‑1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L‑1 d‑1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell‑1 d‑1, which finally led to the stable operation of the system.

  4. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate.

    PubMed

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-01-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g(-1) COD and methane percentages of 53-76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L(-1)) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg(-1) N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L(-1) d(-1) was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68-95 fmol N cell(-1) d(-1), which finally led to the stable operation of the system. PMID:27279481

  5. Integrating landfill bioreactors, partial nitritation and anammox process for methane recovery and nitrogen removal from leachate

    PubMed Central

    Sun, Faqian; Su, Xiaomei; Kang, Tingting; Wu, Songwei; Yuan, Mengdong; Zhu, Jing; Zhang, Xiayun; Xu, Fang; Wu, Weixiang

    2016-01-01

    A new process consisting of a landfill bioreactor, partial-nitritation (PN) and the anammox process has been developed for landfill leachate treatment. In this study, the landfill bioreactor exhibited excellent performance in methane-rich biogas recovery, with a specific biogas yield of 0.47 L gas g−1 COD and methane percentages of 53–76%. PN was achieved in the aerobic reactor by high free ammonia (101 ± 83 mg NH3 L−1) inhibition for nitrite-oxidizing bacteria, and the desired PN effluent composition (effluent nitrite: ammonium ratio of 1.1 ± 0.3) was controlled by adjusting the alkalinity concentration per unit of ammonium oxidized to approximately 14.3 mg CaCO3 mg−1 N in the influent. The startup of anammox process was successfully achieved with a membrane bioreactor in 160 d, and a maximum nitrogen removal rate of 216 mg N L−1 d−1 was attained for real landfill leachate treatment. The quantitative polymerase chain reaction results confirmed that the cell-specific anammox activity was approximately 68–95 fmol N cell−1 d−1, which finally led to the stable operation of the system. PMID:27279481

  6. High-rate nitrogen removal from livestock manure digester liquor by combined partial nitritation-anammox process.

    PubMed

    Qiao, Sen; Yamamoto, Taichi; Misaka, Motoki; Isaka, Kazuichi; Sumino, Tatsuo; Bhatti, Zafar; Furukawa, Kenji

    2010-02-01

    In this study, combination of a partial nitritation reactor, using immobilized polyethylene glycol (PEG) gel carriers, and a continuous stirred granular anammox reactor was investigated for nitrogen removal from livestock manure digester liquor. Successful nitrite accumulation in the partial nitritation reactor was observed as the nitrite production rate reached 2.1 kg-N/m(3)/day under aerobic nitrogen loading rate of 3.8 kg-N/m(3)/day. Simultaneously, relatively high free ammonia concentrations (average 50 mg-NH(3)/l) depressed the activity of nitrite oxidizing bacteria with nitrate concentration never exceeding 3% of TN concentration in the effluent of the partial nitritation reactor (maximum 35.2 mg/l). High nitrogen removal rates were achieved in the granular anammox reactor with the highest removal rate being 3.12 kg-N/m(3)/day under anaerobic nitrogen loading rate of 4.1 kg-N/m(3)/day. Recalcitrant organic compounds in the digester liquor did not impair anammox reaction and the SS accumulation in the granular anammox reactor was minimal. The results of this study demonstrated that partial nitritation-anammox combination has the potential to successfully remove nitrogen from livestock manure digester liquor. PMID:19578828

  7. An Investigation into the Accuracy of Two Currently Available Dental Impression Materials in the Construction of Cobalt-Chromium Frameworks for Removable Partial Dentures.

    PubMed

    Dubal, Rajesh Kumar; Friel, Tim; Taylor, Philip D

    2015-03-01

    This study investigated the suitability of irreversible hydrocolloid as an impression material for cobalt-chromium framework construction. Scans of casts derived from (1) alginate and (2) addition-cured polyvinylsiloxane impressions were superposed on to a control. The differences within and between groups were compared at fixed landmarks. The investigation revealed a high degree of scan coincidence within and between groups. However, certain features, such as undercuts, resulted in a lower degree of scan coincidence. Irreversible hydrocolloid appears to be a viable alternative to addition-cured polyvinyl-siloxane as an impression material for cobalt-chromium framework construction. PMID:26415334

  8. Operational strategy for nitrogen removal from centrate in a two-stage partial nitrification--anammox process.

    PubMed

    Kosari, S F; Rezania, B; Lo, K V; Mavinic, D S

    2014-01-01

    This paper presents the operational strategy for nitrogen removal in a two-stage, partial nitrification (PN) process coupled with anaerobic ammonium oxidation (Anammox) process. The process was used to remove ammonium from centrate obtained from a full-scale, wastewater treatment plant in British Columbia, Canada. The PN, which was carried out in a sequencing batch reactor (SBR), successfully converted approximately 49.5 +/- 1.0% of ammonium to nitrite. The operation of SBR under higher dissolved oxygen in combination with slow feeding resulted in significant reduced HRT without nitrate accumulation. Partially nitrified centrate was further treated in Anammox reactors, where the mixture of ammonium and nitrite was converted mainly to nitrogen gas. Anammox treatment was carried out in two different types of Anammox reactors: a moving bed hybrid reactor and an up-flow fixed-bed biofilm reactor. The hybrid Anammox reactor removed an average of 55.8% of NH4-N, versus the 48.3% NH4-N removed in the up-flow fixed-bed reactor. Nitrite removal in the hybrid and up-flow fixed-bed Anammox reactors averaged 80.8% and 62.5%, respectively. This study also illustrated that in both Anammox reactors, better ammonium removal was achieved when the nitrite to ammonium ratio is between 1.35 and 1.45. As such, alkalinity was found to neither control nor limit the Anammox reaction. PMID:24701906

  9. Assessing distribution of migratory fishes and connectivity following complete and partial dam removals in a North Carolina River

    USGS Publications Warehouse

    Raabe, Joshua K.; Hightower, Joseph E.

    2014-01-01

    Fish, especially migratory species, are assumed to benefit from dam removals that restore connectivity and access to upstream habitat, but few studies have evaluated this assumption. Therefore, we assessed the movement of migratory fishes in the springs of 2008 through 2010 and surveyed available habitat in the Little River, North Carolina, a tributary to the Neuse River, after three complete dam removals and one partial (notched) dam removal. We tagged migratory fishes with PIT tags at a resistance-board weir located at a dam removal site (river kilometer [rkm] 3.7) and followed their movements with an array of PIT antennas. The river-wide distribution of fish following removals varied by species. For example, 24–31% of anadromous American Shad Alosa sapidissima, 45–49% of resident Gizzard Shad Dorosoma cepedianum, and 4–11% of nonnative Flathead CatfishPylodictis olivaris passed the dam removal site at rkm 56 in 2009 and 2010. No preremoval data were available for comparison, but reach connectivity appeared to increase as tagged individuals passed former dam sites and certain individuals moved extensively both upstream and downstream. However, 17–28% did not pass the partially removed dam at rkm 7.9, while 20–39% of those that passed remained downstream for more than a day before migrating upstream. Gizzard Shad required the deepest water to pass this notched structure, followed by American Shad then Flathead Catfish. Fish that passed the notched dam accessed more complex habitat (e.g., available substrate size-classes) in the middle and upper reaches. The results provide strong support for efforts to restore currently inaccessible habitat through complete removal of derelict dams.

  10. Removal of Nitrogen and Phosphorus From Reject Water Using Chlorella vulgaris Algae After Partial Nitrification/Anammox Process.

    PubMed

    Gutwinski, Piotr; Cema, Grzegorz

    2016-01-01

    Wastewater containing nutrients like ammonia, nitrite, nitrate and phosphates have been identified as the main cause of eutrophication in natural waters. Therefore, a suitable treatment is needed. In classical biological processes, nitrogen and phosphorus removal is expensive, especially due to the lack of biodegradable carbon, thus new methods are investigated. In this paper, the new possibility of nitrogen and phosphorus removal in side stream after the partial nitrification/Anammox process is proposed. Research was carried out in a lab-scale vertical tubular photobioreactor (VTR) fed with real reject water, from dewatering of digested sludge, after partial nitrification/Anammox process from lab-scale sequencing batch reactor (SBR). Nitrogen and phosphorus concentrations were measured every three days. The average nitrogen and phosphorus loads were 0.0503 ± 0.036 g N g(vss)/d and 0.0389 ± 0.013 g P g(vss)/d accordingly. Results have shown that microalgae were able to efficiently remove nitrogen and phosphorus. The average nitrogen removal was 36.46% and phosphorus removal efficiency varied between 93 and 100%. PMID:26803028

  11. Allergic effects of the residual monomer used in denture base acrylic resins

    PubMed Central

    Rashid, Haroon; Sheikh, Zeeshan; Vohra, Fahim

    2015-01-01

    Denture base resins are extensively used in dentistry for a variety of purposes. These materials can be classified as chemical, heat, light, and microwave polymerization materials depending upon the factor which starts the polymerization reaction. Their applications include use during denture base construction, relining existing dentures, and for fabrication of orthodontic removable appliances. There have been increased concerns regarding the safe clinical application of these materials as their biodegradation in the oral environment leads to harmful effects. Along with local side effects, the materials have certain occupational hazards, and numerous studies can be found in the literature mentioning those. The purpose of this article is to outline the cytotoxic consequences of denture base acrylic resins and clinical recommendations for their use. PMID:26929705

  12. Denture Adhesives in Prosthodontics: An Overview

    PubMed Central

    Kumar, P Ranjith; Shajahan, P A; Mathew, Jyothis; Koruthu, Anil; Aravind, Prasad; Ahammed, M Fazeel

    2015-01-01

    The use of denture adhesives is common among denture wearers, and it is also prescribed by many dentists. Prescribing denture adhesives has been viewed by many prosthodontists as a means of compensating for any defects in the fabrication procedures. Denture adhesives add to the retention and thereby improve chewing ability, reduce any instability, provide comfort and eliminate the accumulation of food debris beneath the dentures. Consequently, they increase the patient’s sense of security and satisfaction. However, obtaining the advice of the dental practitioner prior to the use of adhesives is a must. PMID:26225115

  13. A novel stoichiometries methodology to quantify functional microorganisms in simultaneous (partial) nitrification-endogenous denitrification and phosphorus removal (SNEDPR).

    PubMed

    Wang, Xiaoxia; Wang, Shuying; Zhao, Ji; Dai, Xian; Li, Baikun; Peng, Yongzhen

    2016-05-15

    Although efficient removal of carbon (C), nitrogen (N) and phosphorous (P) from wastewater with low C/N ratio was achieved in anaerobic/aerobic simultaneous nitrification-endogenous denitrification and phosphorus removal (SNEDPR) systems, the removal pathways and metabolic transformations in this complex system are unclear. This work targeted at developing the stoichiometric models for denitrifying glycogen organisms (DGAOs) via nitrite and nitrate (DGAONi and DGAONa), and demonstrating a novel methodology to quantify diverse functional microorganisms (e.g. ammonia and nitrite oxidizing bacteria, aerobic phosphorus accumulating organisms (APAOs), denitrifying PAOs (DPAOs) and aerobic GAOs (AGAOs)) for the removal of C, N and P. The results showed that the anaerobic intracellular carbon storage (CODintra) was mainly accomplished by GAOs, and PAOs were only responsible for about 40% of CODintra through a stable P release. At the aerobic stage, 84.9% of P was removed by APAOs with 15.1% left by DPAOs, while 64.6% of N was removed by DGAOs (45.8% by DGAONi and 18.8% by DGAONa) with 18.1% by DPAOs and 17.3% by bacterial growth. High proportion of N removal via nitrite (partial nitrification-endogenous denitrification) (71%) saved 7.3% aeration and 38% intracellular carbon demand. However, AGAOs still activated well at the aerobic intercellular carbon consumption, which limited the further improvement of N removal efficiency. By elucidating the nutrient removal pathways among diverse functional microorganisms, the methodology developed in this study could accelerate the nutrient removal in the SNEDPR process. PMID:27016642

  14. Cytotoxicity of denture adhesives.

    PubMed

    de Gomes, Pedro Sousa; Figueiral, Maria Helena; Fernandes, Maria Helena R; Scully, Crispian

    2011-12-01

    Ten commercially available denture adhesives, nine soluble formulations (six creams, three powders) and one insoluble product (pad), were analyzed regarding the cytotoxicity profile in direct and indirect assays using L929 fibroblast cells. In the direct assay, fibroblasts were seeded over the surface of a thick adhesive gel (5%, creams; 2.5%, powders and pad). In the indirect assay, cells were cultured in the presence of adhesive extracts prepared in static and dynamic conditions (0.5-2%, creams; 0.25-1%, powders and pad). Cell toxicity was assessed for cell viability/proliferation (MTT assay) and cell morphology (observation of the F-actin cytoskeleton organization by confocal laser scanning microscopy). Direct contact of the L929 fibroblasts with the thick adhesive gels caused no, or only a slight, decrease in cell viability/proliferation. The adhesive extracts (especially those prepared in dynamic conditions) caused significantly higher growth inhibition of fibroblasts and, in addition, caused dose- and time-dependent effects, throughout the 6-72 h exposure time. Also, dose-dependent effects on cell morphology, with evident disruption of the F-actin cytoskeleton organization, were seen in the presence of most adhesives. In conclusion, the adhesives possessed different degrees of cytotoxicity, but similar dose- and time-dependent biological profiles. PMID:20844908

  15. Dimensional stability of complete denture permanent acrylic resin denture bases; A comparison of dimensions before and after a second curing cycle.

    PubMed

    Fenlon, Michael Robert; Juszczyk, Andrzej Stanislaw; Rodriguez, Jose Mauricio; Curtis, Richard Victor

    2010-03-01

    The purpose of this study was to measure deformation of mandibular complete denture permanent bases after secondary curing. A cast of a flat mandibular edentulous ridge was duplicated ten times. A wax base was laid on the original cast, two wax sprues were attached and an overcast was made. The overcast was used to produce wax bases similar in outline and thickness on the duplicate casts. These were invested and following manufacturer's instructions ten similar acrylic resin bases were produced. The fitting surface of each denture base was scanned on a contacting scanner with an axis resolution of 1 microm and accurate to 25 microm. Denture teeth were waxed up on the base on the original master cast, an overcast was made to produce wax ups and tooth positions that were similar in outline and thickness to the original. These were processed, removed from the flasks and excess acrylic resin was removed. The denture bases were rescanned in an identical fashion to the first scanning procedure. Using commercially developed metrology software calibrated colour maps were generated for each denture base that illustrates measurements of differences between pairs of surfaces. Histograms showing distributions of distances between points were constructed. 50% of the points were separated by a mean 50 microm or less and that 90% of the points were separated by 160 microm or less. The maximum separation was of 380 microm. Complete denture permanent bases were not found to distort significantly as a result of being subjected to a second heat curing cycle as part of final processing of dentures. PMID:20397501

  16. Chronic Maxillary Sinusitis Caused by Denture Lining Material

    PubMed Central

    Sugiura, Tsutomu; Yamamoto, Kazuhiko; Nakashima, Chie; Murakami, Kazuhiro; Matsusue, Yumiko; Horita, Satoshi; Sakagami, Go; Kirita, Tadaaki

    2016-01-01

    We report a case of chronic maxillary sinusitis caused by denture lining material entering through an oroantral fistula after tooth extraction. The patient was an 80-year-old female who visited us with a complaint of pus discharge from the right posterior maxilla. She had extraction of the upper right second molar and had her upper denture relined with silicone lining material. The patient noticed swelling of the right cheek and purulent rhinorrhea 20 days before her first visit to our clinic. Oral examination showed an oroantral fistula with a diameter of 3 mm in the posterior alveolar ridge of the right maxilla. Computed tomography revealed a hyperdense foreign body in the right maxillary sinus and thickening of the mucosal lining. Under diagnosis of maxillary sinusitis caused by a foreign body, endoscopic maxillary surgery was performed simultaneously with the removal of the foreign body. The foreign body removed was 12 × 6 mm in size, oval in shape, light pink in color, and compatible with silicone denture lining material. During the follow-up it was observed that the oroantral fistula closed spontaneously after the removal of the foreign body. The maxillary sinus was in a good shape without recurrence of sinusitis seven months after surgery. PMID:27386012

  17. The effect of magnesium on partial sulphate removal from mine water as gypsum.

    PubMed

    Tolonen, Emma-Tuulia; Rämö, Jaakko; Lassi, Ulla

    2015-08-15

    The aim of this research was to investigate the effect of magnesium on the removal efficiency of sulphate as gypsum from mine water. The precipitation conditions were simulated with MINEQL + software and the simulation results were compared with the results from laboratory jar test experiments. Both the simulation and the laboratory results showed that magnesium in the mine water was maintaining sulphate in a soluble form as magnesium sulphate (MgSO4) at pH 9.6. Thus magnesium was preventing the removal of sulphate as gypsum (CaSO4·2H2O). However, change in the lime precipitation pH from 9.6 to 12.5 resulted in magnesium hydroxide (Mg(OH)2) precipitation and improved sulphate removal. Additionally, magnesium hydroxide could act as seed crystals for gypsum precipitation or co-precipitate sulphate further enhancing the removal of sulphate from mine water. PMID:26067895

  18. The impact of frenulum height on strains in maxillary denture bases

    PubMed Central

    Bilhan, Hakan; Baysal, Gokhan; Sunbuloglu, Emin; Bozdag, Ergun

    2013-01-01

    PURPOSE The midline fracture of maxillary complete dentures is a frequently encountered complication. The purpose of this study was to assess the effect of frenulum height on midline strains of maxillary complete dentures. MATERIALS AND METHODS A removable maxillary complete denture was fabricated and duplicated seven times. Four different labial frenulum heights were tested for stresses occurring on the palatal cameo surface. The strains were measured with strain gauges placed on 5 different locations and the stresses were calculated. To mimic occlusal forces bilaterally 100 N of load was applied from the premolar and molar region. RESULTS A statistically significant association between the height of the labial frenulum and the calculated stresses and strains was shown (P<.05) predominantly on the midline and especially on the incisive papilla. The results showed that stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum. CONCLUSION Within the limitations of this in vitro study, it can be concluded that the stress on the anterior midline of the maxillary complete denture increases with a higher labial frenulum. Surgical or mechanical precautions should be taken to prevent short-term failure of maxillary complete dentures due to stress concentration and low cycle fatigue tendency at the labial frenulum region. PMID:24353878

  19. Evidence-based considerations for removable prosthodontic and dental implant occlusion: a literature review.

    PubMed

    Taylor, Thomas D; Wiens, Jonathan; Carr, Alan

    2005-12-01

    The dental literature is filled with discussions of dental occlusion, occlusal schemes, philosophies, and methods to correct and restore the diseased, worn, or damaged occlusion. Traditionally, these discussions have been empirical in nature and not based on scientific evidence. Due to the empirical nature of the literature, the study of occlusion has been extremely complex and troublesome to both pre- and post-doctoral students. The introduction of osseointegrated implants has further complicated the situation. Dentists may apply the principles of occlusion for the natural dentition directly to implant-supported and retained restorations. Although this may be successful, this rationale may result in overly complex or simplified treatment protocols and outcomes. There is an emerging body of scientific literature related to dental implant therapy that may be useful in formulating treatment protocols and prosthesis designs for implant-supported restorations. This review focuses on some of the "classic" removable prosthodontic literature and the currently available scientific literature involving removable prosthodontic occlusion and dental implant occlusion. The authors reviewed the English peer-reviewed literature prior to 1996 in as comprehensive manner as possible, and material after 1996 was reviewed electronically using MEDLINE. Electronic searches of the literature were performed in MEDLINE using key words-animal studies, case series, clinical trials, cohort studies, complete denture occlusion, dental implant function, dental implant occlusion, dental implant occlusion research, dental implant functional loading, dental implants, dental occlusion, dental occlusion research, denture function, denture occlusion, dentures, implant function, implant functional loading, implant occlusion, occlusion, and removable partial denture occlusion-in various combinations to obtain potential references for review. A total of 5447 English language titles were obtained, many of

  20. Impacts from Partial Removal of Decommissioned Oil and Gas Platforms on Fish Biomass and Production on the Remaining Platform Structure and Surrounding Shell Mounds

    PubMed Central

    Claisse, Jeremy T.; Pondella, Daniel J.; Love, Milton; Zahn, Laurel A.; Williams, Chelsea M.; Bull, Ann S.

    2015-01-01

    When oil and gas platforms become obsolete they go through a decommissioning process. This may include partial removal (from the surface to 26 m depth) or complete removal of the platform structure. While complete removal would likely eliminate most of the existing fish biomass and associated secondary production, we find that the potential impacts of partial removal would likely be limited on all but one platform off the coast of California. On average 80% of fish biomass and 86% of secondary fish production would be retained after partial removal, with above 90% retention expected for both metrics on many platforms. Partial removal would likely result in the loss of fish biomass and production for species typically found residing in the shallow portions of the platform structure. However, these fishes generally represent a small proportion of the fishes associated with these platforms. More characteristic of platform fauna are the primarily deeper-dwelling rockfishes (genus Sebastes). “Shell mounds” are biogenic reefs that surround some of these platforms resulting from an accumulation of mollusk shells that have fallen from the shallow areas of the platforms mostly above the depth of partial removal. We found that shell mounds are moderately productive fish habitats, similar to or greater than natural rocky reefs in the region at comparable depths. The complexity and areal extent of these biogenic habitats, and the associated fish biomass and production, will likely be reduced after either partial or complete platform removal. Habitat augmentation by placing the partially removed platform superstructure or some other additional habitat enrichment material (e.g., rock boulders) on the seafloor adjacent to the base of partially removed platforms provides additional options to enhance fish production, potentially mitigating reductions in shell mound habitat. PMID:26332384

  1. Effects of denture teeth on the dimensional accuracy of acrylic resin denture bases.

    PubMed

    Baemmert, R J; Lang, B R; Barco, M T; Billy, E J

    1990-01-01

    The Michigan Computer-Graphics Coordinate Measurement System was used to determine the effects of artificial denture teeth on the accuracy of acrylic resin denture bases. Two poly(methyl methacrylate) acrylic resins and two processing techniques were tested. Groups processed with denture teeth reproduced more accurate points than groups processed without denture teeth. Groups processed with a conventional heat-polymerized acrylic resin reproduced more accurate points than groups polymerized with an injection pressing type of acrylic resin. PMID:2083021

  2. Enhanced ammonia removal at room temperature by pH controlled partial nitrification and subsequent anaerobic ammonium oxidation.

    PubMed

    Durán, U; del Val Río, A; Campos, J L; Mosquera-Corral, A; Méndez, R

    2014-01-01

    The Anammox-based processes are suitable for the treatment of wastewaters characterized by a low carbon to nitrogen (C/N) ratio. The application of the Anammox process requires the availability of an effluent with a NO2- -N/NH4+ -N ratio composition around 1 g g-1, which involves the necessity of a previous step where the partial nitrification is performed. In this step, the inhibition of the nitrite-oxidizing bacteria (NOB) is crucial. In the present work, a combined partial nitrification-ANaerobic AMmonia OXidation (Anammox) two-units system operated at room temperature (20 degreeC) has been tested for the nitrogen removal of pre-treated pig slurry. To achieve the successful partial nitrification and inhibit the NOB activity, different ammonium/inorganic carbon (NH4+/IC) ratios were assayed from 1.19 to 0.82g NH4+-Ng-1 HCO3-C. This procedure provoked a decrease of the pH value to 6.0 to regulate the inhibitory effect over ammonia-oxidizing bacteria caused by free ammonia. Simultaneously, the NOB experienced the inhibitory effect of free nitrous acid which avoided the presence of nitrate in the effluent. The NH4+/IC ratio which allowed the obtaining of the desired effluent composition (50% of both ammonium and nitrite) was 0.82 +/- 0.02 g NH4+-N g-1 HCO3- -C. The Anammox reactor was fed with the effluent of the partial nitrification unit containing a NO2 -N/NH4+ -N ratio of 1 g g-1' where a nitrogen loading rate of 0.1 g N L-1 d-1 was efficiently removed. PMID:24600878

  3. Successful removal of a partial Siamese twin with a carbon dioxide laser.

    PubMed

    Joubert, M; Stephanov, S

    1983-11-26

    A case of a 'partial Siamese twin' is discussed, and the neurological signs and operative findings are recorded. The operation was performed with the aid of a carbon dioxide laser, which not only facilitated and expedited the procedure but also ensured minimal loss of blood. The wound broke down in part, but complete healing occurred within less than a month. At the time of discharge the baby showed no abnormal neurological signs. PMID:6635892

  4. On the removal of boundary errors caused by Runge-Kutta integration of non-linear partial differential equations

    NASA Technical Reports Server (NTRS)

    Abarbanel, Saul; Gottlieb, David; Carpenter, Mark H.

    1994-01-01

    It has been previously shown that the temporal integration of hyperbolic partial differential equations (PDE's) may, because of boundary conditions, lead to deterioration of accuracy of the solution. A procedure for removal of this error in the linear case has been established previously. In the present paper we consider hyperbolic (PDE's) (linear and non-linear) whose boundary treatment is done via the SAT-procedure. A methodology is present for recovery of the full order of accuracy, and has been applied to the case of a 4th order explicit finite difference scheme.

  5. Partial nitritation and o-cresol removal with aerobic granular biomass in a continuous airlift reactor.

    PubMed

    Jemaat, Zulkifly; Suárez-Ojeda, María Eugenia; Pérez, Julio; Carrera, Julián

    2014-01-01

    Several chemical industries produce wastewaters containing both, ammonium and phenolic compounds. As an alternative to treat this kind of complex industrial wastewaters, this study presents the simultaneous partial nitritation and o-cresol biodegradation in a continuous airlift reactor using aerobic granular biomass. An aerobic granular sludge was developed in the airlift reactor for treating a high-strength ammonium wastewater containing 950 ± 25 mg N-NH4(+) L(-1). Then, the airlift reactor was bioaugmented with a p-nitrophenol-degrading activated sludge and o-cresol was added progressively to the ammonium feed to achieve 100 mg L(-1). The results showed that stable partial nitritation and full biodegradation of o-cresol were simultaneously maintained obtaining a suitable effluent for a subsequent anammox reactor. Moreover, two o-cresol shock-load events with concentrations of 300 and 1000 mg L(-1) were applied to assess the capabilities of the system. Despite these shock load events, the partial nitritation process was kept stable and o-cresol was totally biodegraded. Fluorescence in situ hybridization technique was used to identify the heterotrophic bacteria related to o-cresol biodegradation and the ammonia oxidising bacteria along the granules. PMID:24140352

  6. Microbiological analysis after complete or partial removal of carious dentin using two different techniques in primary teeth: A randomized clinical trial

    PubMed Central

    Singhal, Deepak Kumar; Acharya, Shashidhar; Thakur, Arun Singh

    2016-01-01

    Background: The management of deep carious lesions can be done by various techniques but residual caries dilemma still persists and bacterial reduction in cavities treated by either partial or complete caries removal techniques is debatable. So the objective of the present randomized clinical trial was to compare microbial counts in cavities submitted to complete caries removal and partial caries removal using either hand instruments or burs before and after 3 weeks of restoration. Materials and Methods: Primary molars with acute carious lesions in inner half of dentine and vital pulp were randomly divided into three groups of 14 each: Group A: Partial caries removal using hand instruments atraumatic restorative treatment (ART) only; Group B: Partial caries removal using bur; Group C: Complete caries removal using bur and caries detector dye. Dentine sample obtained after caries removal and 3 weeks after restoration, were subjected to microbial culture and counting (colony-forming units [CFU]/mg of dentine) for total viable bacterial count, Streptococcus spp., mutans streptococci, Lactobacillus spp. Results: Three techniques of caries removal showed significant (P < 0.05) reduction in all microorganisms studied after 3 weeks of evaluation, but there was no statistically significant difference in percentage reduction of microbial count among three groups. Conclusion: Results suggest the use of partial caries removal in a single session as compared to complete caries removal as a part of treatment of deep lesions in deciduous teeth in order to reduce the risk of pulp exposure. Partial caries removal using ART can be preferred for community settings as public health procedure for caries management. PMID:26962313

  7. Fourth-order partial differential equation noise removal on welding images

    SciTech Connect

    Halim, Suhaila Abd; Ibrahim, Arsmah; Sulong, Tuan Nurul Norazura Tuan; Manurung, Yupiter HP

    2015-10-22

    Partial differential equation (PDE) has become one of the important topics in mathematics and is widely used in various fields. It can be used for image denoising in the image analysis field. In this paper, a fourth-order PDE is discussed and implemented as a denoising method on digital images. The fourth-order PDE is solved computationally using finite difference approach and then implemented on a set of digital radiographic images with welding defects. The performance of the discretized model is evaluated using Peak Signal to Noise Ratio (PSNR). Simulation is carried out on the discretized model on different level of Gaussian noise in order to get the maximum PSNR value. The convergence criteria chosen to determine the number of iterations required is measured based on the highest PSNR value. Results obtained show that the fourth-order PDE model produced promising results as an image denoising tool compared with median filter.

  8. [Effect of High Ammonium on Nitrogen Removal in an Partial Nitritation-ANAMMOX Process with Reflux System].

    PubMed

    Li, Xiang; Cui, Jian-hong; Yuan, Yan; Huang, Yong; Yuan, Yi; Liu, Xin

    2015-10-01

    The effect of influent ammonia on nitrogen transformation characteristics and microbial communities in partial nitrification-anaerobic ammonia oxidation (PN-ANAMMOX) process was studied by using a series of partial nitrification and ANAMMOX process with air-lift reflux device. The results showed that when the influent ammonia concentration was increased to 700 mg x L(-1) and the nitrogen volume load was stabled at 2.8 kg x (m3 x d)(-1), the fluctuation of pH value was very small in aerobic and anaerobic zone. In the aerobic and anaerobic zone, FA concentrations were maintained at 5'mg x L(-1), 10 mg x L(-1), respectively, which did not inhibit the growth of microorganisms. Nitrite produce rate was stabled at 1.5 kg x (m3 x d)(-1) in the aerobic zone, and nitrogen removal rate was stabled at 31.49 kg x (m3 x d)(-1) in anaerobic zone, the total nitrogen removal rate was stabled at 1.67 kg x (m3 x d)(-1) in combined process. When the influent ammonia concentration was increased to 900 mg x L(-1), the FA and FNA concentration were increased in each areas, total nitrogen removal rate was decreased and stabled at 1.52 kg x- ( m3x- d( 1)'. The nitrite was accumulated in the anaerobic zone, and there was no significant inhibition of ANAMMOX bacteria. Our findings indicated that the reflux can effectively alleviate the fluctuation of pH in each area, and dilute FA concentration which is toxic to microorganisms. PMID:26841608

  9. Sealing versus partial caries removal in primary molars: a randomized clinical trial

    PubMed Central

    2014-01-01

    Background The resin-based pit and fissure sealant is considered a successful tool in caries prevention, however there is a growing evidence of its use in controlling already established caries in posterior teeth. The aim of this clinical trial is to verify the efficacy of pit and fissure sealants in arresting dentinal caries lesions compared to partial excavation and restorative treatment in primary molar teeth. Methods Thirty six patients with occlusal cavitated primary molar reaching outer half of dentin were selected. The patients were randomly allocated into two groups: sealant application (experimental group – n = 17) and restoration with composite resin (control group – n = 19). Clinical and radiograph evaluation were performed after 6, 12 and 18 months. The chi-square test was used to verify the distribution of characteristics variables of the sample among the groups. The survival rate of treatments was evaluated using Kaplan–Meier survival and log-rank test. Fisher’s Exact and logistic regression tests were calculated in each evaluation period (α = 5%). Results The control group showed significantly better clinical survival after 18 months (p = 0.0025). In both groups, no caries progression was registered on the radiographic evaluations. Conclusions Sealing had similar efficacy in the arrestment of caries progression of cavitated occlusal lesions compared to partial excavation of the lesions, even though the frequency of re-treatments was significantly higher in sealed lesions. Trial registration Registro Brasileiro de Ensaios Clínicos (ReBEC): RBR-9kkv53 PMID:24884684

  10. A practical three visit complete denture system.

    PubMed

    Ling, B C

    2000-10-01

    Standard prosthodontic procedures require five visits to construct a set of complete maxillary and mandibular dentures. Various attempts have been made to reduce these procedures to four or three appointments. However, most of these techniques require the use of visible light polymerized resin as the final denture base materials. Visible light-cured resin materials have inferior physical properties and biocompatibility problems as compared with heat cured polymethylmethacrylate. This paper describes a system of complete denture construction which requires three clinical appointments instead of the usual five visits. This system is made possible by using the VLC base/tray material as the preliminary impression material as well as the application of a new biometric wax occlusion rim. It retains the use of polymethylmethacrylate as the denture base material. This system also utilizes all the procedures used in the conventional five appointment system of complete denture construction. PMID:11709981

  11. Effects of offset values for artificial teeth positions in CAD/CAM complete denture.

    PubMed

    Yamamoto, Shinta; Kanazawa, Manabu; Iwaki, Maiko; Jokanovic, Ana; Minakuchi, Shunsuke

    2014-09-01

    Recently, computer-aided design/computer-aided manufacturing (CAD/CAM) technology has been applied to the field of removable complete denture prosthodontics. We developed a system for fabricating complete dentures applying CAD/CAM technology. In this system, artificial teeth were bonded to the recesses of a milled denture base. However, the offset values needed for the recesses are not known. The purpose of the present study was to evaluate the accuracy of bonded artificial teeth positions in 0.00 (control), 0.10, 0.15, 0.20, and 0.25mm offset recess groups. Four types of artificial teeth, upper left central incisor (UL1), upper left canine (UL3), upper left first premolar (UL4), and upper left first molar (UL6), were used. Each type of artificial tooth was arranged at regular intervals on the denture base model with the CAD software. These data were defined as the master data. The artificial teeth parts were subtracted from the denture base model by Boolean logic operations in order to make recesses, and the recesses were then offset in five values. Based on these denture base data, prepolymerized resin blocks were milled (n=3). After bonding artificial teeth on the milled denture base model, a cone beam computed tomography (CBCT) scan was performed to obtain scanned data. Deviations between the master data and the scanned data were calculated. Based on the results, the optimal offset values were found to be 0.15-0.25mm for UL1, 0.15 and 0.25mm for UL3, 0.25mm for UL4, and 0.10-0.25mm for UL6. PMID:24981734

  12. Effect of Different Denture Base Materials and Changed Mouth Temperature on Dimensional Stability of Complete Dentures

    PubMed Central

    Arafa, Khalid A. O.

    2016-01-01

    Background. Type of materials used in fabrication of denture base has an effect on dimension during denture base material processing and other factors related to clinical use. Objective. The study aims were to assess the dimensional stability including thermal changes of three different denture base materials. Methods. Ninety patients were selected to construct complete dentures with different denture base materials. They were randomly divided into three groups: group 1, patients with cobalt chrome metallic base; group 2, patients with heat curing acrylic resin fabricated by injection moulding technique; and group 3, patients with denture bases fabricated by conventional heat curing acrylic resin. The dimensional changes were assessed using digital caliper. Results. After the twelfth month, injection moulding acrylic resin had significantly the highest dimensional change followed by the conventional heat curing acrylic resin. There were no significant differences in the dimensions between the three types of denture base materials at normal mouth temperature, while, after hot tea drinking at 45°C, the dimensional change was significantly the highest in cobalt chrome metallic denture base group. Conclusion. Cobalt chrome metallic denture base has stable dimension compared to denture bases fabricated of acrylic resin but it was more affected by altered mouth temperature. The study was registered in the International Standard Randomized Controlled Trials Number (ISRCTN) registry with study ID (ISRCTN94238244). PMID:27143970

  13. Effect of Different Denture Base Materials and Changed Mouth Temperature on Dimensional Stability of Complete Dentures.

    PubMed

    Arafa, Khalid A O

    2016-01-01

    Background. Type of materials used in fabrication of denture base has an effect on dimension during denture base material processing and other factors related to clinical use. Objective. The study aims were to assess the dimensional stability including thermal changes of three different denture base materials. Methods. Ninety patients were selected to construct complete dentures with different denture base materials. They were randomly divided into three groups: group 1, patients with cobalt chrome metallic base; group 2, patients with heat curing acrylic resin fabricated by injection moulding technique; and group 3, patients with denture bases fabricated by conventional heat curing acrylic resin. The dimensional changes were assessed using digital caliper. Results. After the twelfth month, injection moulding acrylic resin had significantly the highest dimensional change followed by the conventional heat curing acrylic resin. There were no significant differences in the dimensions between the three types of denture base materials at normal mouth temperature, while, after hot tea drinking at 45°C, the dimensional change was significantly the highest in cobalt chrome metallic denture base group. Conclusion. Cobalt chrome metallic denture base has stable dimension compared to denture bases fabricated of acrylic resin but it was more affected by altered mouth temperature. The study was registered in the International Standard Randomized Controlled Trials Number (ISRCTN) registry with study ID (ISRCTN94238244). PMID:27143970

  14. Complete denture fabrication with CAD/CAM record bases.

    PubMed

    McLaughlin, J Bryan; Ramos, Van

    2015-10-01

    One of the primary goals of new materials and processes for complete denture fabrication has been to reduce polymerization shrinkage. The introduction of computer-aided design and computer-aided manufacturing (CAD/CAM) technology into complete denture fabrication has eliminated polymerization shrinkage in the definitive denture. The use of CAD/CAM record bases for complete denture fabrication can provide a better-fitting denture with fewer postprocessing occlusal errors. PMID:26139040

  15. Effect of denture cleansers on metal ion release and surface roughness of denture base materials.

    PubMed

    Davi, Letícia Resende; Felipucci, Daniela Nair Borges; de Souza, Raphael Freitas; Bezzon, Osvaldo Luiz; Lovato-Silva, Cláudia Helena; Pagnano, Valéria Oliveira; Paranhos, Helena de Freitas Oliveira

    2012-01-01

    Chemical disinfectants are usually associated with mechanical methods to remove stains and reduce biofilm formation. This study evaluated the effect of disinfectants on release of metal ions and surface roughness of commercially pure titanium, metal alloys, and heat-polymerized acrylic resin, simulating 180 immersion trials. Disk-shaped specimens were fabricated with commercially pure titanium (Tritan), nickel-chromium-molybdenum-titanium (Vi-Star), nickel-chromium (Fit Cast-SB Plus), and nickel-chromium-beryllium (Fit Cast-V) alloys. Each cast disk was invested in the flasks, incorporating the metal disk to the heat-polymerized acrylic resin. The specimens (n=5) were immersed in these solutions: sodium hypochlorite 0.05%, Periogard, Cepacol, Corega Tabs, Medical Interporous, and Polident. Deionized water was used as a control. The quantitative analysis of metal ion release was performed using inductively coupled plasma mass spectrometry (ELAN DRC II). A surface analyzer (Surftest SJ-201P) was used to measure the surface roughness (µm). Data were recorded before and after the immersions and evaluated by two-way ANOVA and Tukey's test (α=0.05). The nickel release proved most significant with the Vi-Star and Fit Cast-V alloys after immersion in Medical Interporous. There was a significant difference in surface roughness of the resin (p=0.011) after immersion. Cepacol caused significantly higher resin roughness. The immersion products had no influence on metal roughness (p=0.388). It could be concluded that the tested alloys can be considered safe for removable denture fabrication, but disinfectant solutions as Cepacol and Medical Interporous tablet for daily denture immersion should be used with caution because it caused greater resin surface roughness and greater ion release, respectively. PMID:23207854

  16. Feasibility of enhancing the DEnitrifying AMmonium OXidation (DEAMOX) process for nitrogen removal by seeding partial denitrification sludge.

    PubMed

    Cao, Shenbin; Peng, Yongzhen; Du, Rui; Wang, Shuying

    2016-04-01

    The recently proposed DEnitrifying AMmonium OXidation (DEAMOX) process combined anaerobic ammonia oxidation (ANAMMOX) with denitrification to convert nitrate to nitrite, which was a promising way for treating wastewater containing nitrate and ammonia. This study investigated the feasibility of establishing DEAMOX process by seeding partial denitrification sludge (NO3(-) → NO2(-)) using sodium acetate as an electron donor in a sequencing batch reactor. Results showed that the DEAMOX process was established successfully and operated stably in 114-days operation. The average effluent total nitrogen concentration was below 5 mg L(-1) and TN removal efficiency reached up to 97% at COD/NO3(-) ratio of 3.0 under initial NH4(+) concentration of 25 mg L(-1) and NO3(-) of 30 mg L(-1). It suggested that the presence of NO2(-) in the system supplied for ANAMMOX and the relatively long sludge retention time (SRT) for denitrifiers were attributed to commendable coexistence of ANAMMOX and denitrifying bacteria. PMID:26829308

  17. Fabrication of a CAD/CAM monolithic zirconia crown to fit an existing partial removable dental prosthesis.

    PubMed

    Paek, Janghyun; Noh, Kwantae; Pae, Ahran; Lee, Hyeonjong; Kim, Hyeong-Seob

    2016-08-01

    Fabricating a surveyed prosthesis beneath an existing partial removable dental prosthesis (PRDP) is a challenging and time-consuming procedure. The computer-aided design/computer-assisted manufacturing (CAD/CAM) technology was applied to fabricate a retrofitted, surveyed zirconia prosthesis to an existing PRDP. CAD/CAM technology enabled precise and easy replication of the contour of the planned surveyed crown on the existing abutment tooth. This technology ensured excellent adaptation and fit of newly fabricated crown to the existing PRDP with minimal adjustments. In this case report, a seventy-year-old male patient presented with fractured existing surveyed crown. Because the existing PRDP was serviceable, new crown was fabricated to the existing PRDP. PMID:27555903

  18. Fabrication of a CAD/CAM monolithic zirconia crown to fit an existing partial removable dental prosthesis

    PubMed Central

    2016-01-01

    Fabricating a surveyed prosthesis beneath an existing partial removable dental prosthesis (PRDP) is a challenging and time-consuming procedure. The computer-aided design/computer-assisted manufacturing (CAD/CAM) technology was applied to fabricate a retrofitted, surveyed zirconia prosthesis to an existing PRDP. CAD/CAM technology enabled precise and easy replication of the contour of the planned surveyed crown on the existing abutment tooth. This technology ensured excellent adaptation and fit of newly fabricated crown to the existing PRDP with minimal adjustments. In this case report, a seventy-year-old male patient presented with fractured existing surveyed crown. Because the existing PRDP was serviceable, new crown was fabricated to the existing PRDP. PMID:27555903

  19. A case with tumor of left parotid gland and denture stomatitis.

    PubMed

    MercuŢ, Veronica; Iorgulescu, Daniel; Popescu, Sanda Mihaela; Mărgăritescu, Claudiu; MercuŢ, Răzvan; CrăiŢoiu, Monica Mihaela; Scrieciu, Monica

    2015-01-01

    The article discuss the case of an edentulous patient presented to the dental clinic for pain and burning sensation of oral mucosa and diagnosed subsequently with oxyphilic adenoma. A 58-year-old patient, with maxillary edentulism, treated with complete denture, presented to the Clinic of Prosthetic Dentistry of the Faculty of Dental Medicine, University of Medicine and Pharmacy of Craiova, Romania, for pain of oral mucosa and bad stability of denture. The diagnosis of erythematous denture stomatitis as consequence of salivary flow reduction was establish after patient's clinical examination, and by unstimulated sialometry. Clinical exam suggested hyposalivation could be a consequence of a tumor situated at the level of the left parotid gland. The echography confirmed the diagnosis of left parotid gland tumor. The tumor was surgical removed and histopathological exam confirmed oxyphilic adenoma. Education of patient for wearing new denture while maintaining a strict oral hygiene and dealing with low salivary flow was the treatment for denture stomatitis. General dentist has an important role in finding and diagnosing patients with systemic diseases, especially salivary tumors. PMID:25826511

  20. [Zirconia in removable prosthodontics. A case report].

    PubMed

    Bühler, Nico M; Teubner, Eckart; Marinello, Carlo P

    2011-01-01

    Zirconia as a framework material is well established in fixed prosthodontics. However, for its application for removable dentures little experience exists. Zirkonzahn® has developed a copy-milling unit, that is a manually operated machine for the manufacture not only of frameworks but also of complete removable dentures. The aim of this case report is to show the step-by-step clinical and technical fabrication of a zirconia bar on implants and of a corresponding zirconia complete denture. The advantages and disadvantages of the system are presented and problems are critically discussed. PMID:21861249

  1. Partial Edentulism and its Correlation to Age, Gender, Socio-economic Status and Incidence of Various Kennedy’s Classes– A Literature Review

    PubMed Central

    Krishnan, Chitra Shankar

    2015-01-01

    Partial edentulism, one or more teeth missing is an indication of healthy behaviour of dental practices in the society and attitude towards dental and oral care. The pattern of partial edentulism has been evaluated in many selected populations in different countries by different methods. Most of the studies have evaluated partial edentulism by surveying of Removable Partial Dentures (RPDs), patients visiting clinics, clinical records and population in particular locality. The objective of the study is to review the prevalence of partial edentulousness and its correlation to age,gender, arch predominance, socio economic factors and incidence of various Kennedy’s Classes. Key observations drawn from the review are as below. There is no gender correlation for partial edentulism.Prevalence of partial edentulism is more common in mandibular arch than maxillary arch.Younger adults have more Class III and IV RPDs. Elders have more distal extension RPDs Class I and II. PMID:26266237

  2. Bronchial dentures as a cause of airway actinomycosis

    PubMed Central

    Murray, Michelle A; Rogan, Mark P; Morgan, Ross K; Linnane, Seamus J

    2014-01-01

    A 65-year-old man was referred to the respiratory clinic with recurrent chest infections on a background of stage 3 chronic obstructive pulmonary disease. On examination, there was wheeze bilaterally more marked on the left lower lobe. Subsequent imaging revealed an obstruction of the left main bronchus that was concerning for malignancy. Initially, on flexible bronchoscopy, a hard mass was found and multiple biopsies were positive for actinomycosis. Subsequent rigid bronchoscopy was undertaken and a set of dentures were removed from the airway. PMID:25150232

  3. Transcription Factors Efg1 and Bcr1 Regulate Biofilm Formation and Virulence during Candida albicans-Associated Denture Stomatitis

    PubMed Central

    Yano, Junko; Yu, Alika; Fidel, Paul L.; Noverr, Mairi C.

    2016-01-01

    Denture stomatitis (DS) is characterized by inflammation of the oral mucosa in direct contact with dentures and affects a significant number of otherwise healthy denture wearers. The disease is caused by Candida albicans, which readily colonizes and form biofilms on denture materials. While evidence for biofilms on abiotic and biotic surfaces initiating Candida infections is accumulating, a role for biofilms in DS remains unclear. Using an established model of DS in immunocompetent animals, the purpose of this study was to determine the role of biofilm formation in mucosal damage during pathogenesis using C. albicans or mutants defective in morphogenesis (efg1-/-) or biofilm formation (bcr1-/-). For in vivo analyses, rats fitted with custom dentures, consisting of fixed and removable parts, were inoculated with wild-type C. albicans, mutants or reconstituted strains and monitored weekly for fungal burden (denture and palate), body weight and tissue damage (LDH) for up to 8 weeks. C. albicans wild-type and reconstituted mutants formed biofilms on dentures and palatal tissues under in vitro, ex vivo and in vivo conditions as indicated by microscopy demonstrating robust biofilm architecture and extracellular matrix (ECM). In contrast, both efg1-/- and bcr1-/- mutants exhibited poor biofilm growth with little to no ECM. In addition, quantification of fungal burden showed reduced colonization throughout the infection period on dentures and palates of rats inoculated with efg1-/-, but not bcr1-/-, compared to controls. Finally, rats inoculated with efg1-/- and bcr1-/- mutants had minimal palatal tissue damage/weight loss while those inoculated with wild-type or reconstituted mutants showed evidence of tissue damage and exhibited stunted weight gain. These data suggest that biofilm formation is associated with tissue damage during DS and that Efg1 and Bcr1, both central regulators of virulence in C. albicans, have pivotal roles in pathogenesis of DS. PMID:27453977

  4. Transcription Factors Efg1 and Bcr1 Regulate Biofilm Formation and Virulence during Candida albicans-Associated Denture Stomatitis.

    PubMed

    Yano, Junko; Yu, Alika; Fidel, Paul L; Noverr, Mairi C

    2016-01-01

    Denture stomatitis (DS) is characterized by inflammation of the oral mucosa in direct contact with dentures and affects a significant number of otherwise healthy denture wearers. The disease is caused by Candida albicans, which readily colonizes and form biofilms on denture materials. While evidence for biofilms on abiotic and biotic surfaces initiating Candida infections is accumulating, a role for biofilms in DS remains unclear. Using an established model of DS in immunocompetent animals, the purpose of this study was to determine the role of biofilm formation in mucosal damage during pathogenesis using C. albicans or mutants defective in morphogenesis (efg1-/-) or biofilm formation (bcr1-/-). For in vivo analyses, rats fitted with custom dentures, consisting of fixed and removable parts, were inoculated with wild-type C. albicans, mutants or reconstituted strains and monitored weekly for fungal burden (denture and palate), body weight and tissue damage (LDH) for up to 8 weeks. C. albicans wild-type and reconstituted mutants formed biofilms on dentures and palatal tissues under in vitro, ex vivo and in vivo conditions as indicated by microscopy demonstrating robust biofilm architecture and extracellular matrix (ECM). In contrast, both efg1-/- and bcr1-/- mutants exhibited poor biofilm growth with little to no ECM. In addition, quantification of fungal burden showed reduced colonization throughout the infection period on dentures and palates of rats inoculated with efg1-/-, but not bcr1-/-, compared to controls. Finally, rats inoculated with efg1-/- and bcr1-/- mutants had minimal palatal tissue damage/weight loss while those inoculated with wild-type or reconstituted mutants showed evidence of tissue damage and exhibited stunted weight gain. These data suggest that biofilm formation is associated with tissue damage during DS and that Efg1 and Bcr1, both central regulators of virulence in C. albicans, have pivotal roles in pathogenesis of DS. PMID:27453977

  5. Genotypic Diversity and Virulence Traits of Streptococcus mutans Isolated from Carious Dentin after Partial Caries Removal and Sealing

    PubMed Central

    Damé-Teixeira, Nailê; Arthur, Rodrigo Alex; Parolo, Clarissa Cavalcanti Fatturi

    2014-01-01

    The aim of this study was to compare the genotypic diversity and virulence traits of Streptococcus mutans isolated from carious dentin before and after partial dentin caries removal (PDR) and sealing. Carious dentin samples were obtained three months before and after the PDR and cavity sealing. Up to seven isolates of each morphological type of S. mutans were selected and strain identity was confirmed using gtfB primer. Genotyping was performed by arbitrary primer-PCR (AP-PCR). Acidogenesis and acidurance of the genotypes were evaluated as virulence traits. A paired t-test and a Wilcoxon test were used to compare the virulence of genotypes. A total of 48 representative S. mutans isolates were genotyped (31 before and 17 after the sealing). At least one of the genotypes found before the sealing was also found on dentin after the sealing. The number of genotypes found before the sealing ranged from 2 to 3 and after the sealing from 1 to 2 genotypes. No difference was observed in the acidogenesis and acidurance between genotypes isolated before and after the sealing. In conclusion, genotypic diversity of S. mutans decreased after the PDR and sealing, but the virulence traits of S. mutans remained unchangeable. PMID:24578618

  6. Optimized removal of the tongue-and-groove underdose via constrained partial synchronization and variable depth recursion

    NASA Astrophysics Data System (ADS)

    Siochi, R. Alfredo C.

    2009-03-01

    Full synchronization (FS) leaf sequencing removes tongue-and-groove underdosages (TGU) but increases the number of segments. Constrained partial synchronization (CPS) uses a minimum tongue-and-groove ratio (TGR) to reduce the number of segments while achieving acceptable TGUs. TGR is the ratio of non-overlapping intensities that irradiate a common junction. For TGRs of 1, 1.5 and 2, the TGUs were measured as 18%, 4% and 0%, respectively, for a 6 MV beam and a Siemens 82 leaf MLC. The extraction and sweep processes of the variable depth recursion (VDR) leaf-sequencing algorithm were constrained to satisfy a minimum TGR. For a Siemens MLC and 15 clinical cases, VDR with a TGR = 1.5 produced 7% more segments than the unsynchronized VDR, while a fully synchronized sweeping window algorithm produces 62% more segments. For random intensity maps, VDR with CPS produced significantly fewer segments than an unsynchronized sweeping window. Similar results can be obtained for MLCs that interdigitate. This has implications for direct aperture optimization algorithms (DAO) that use the sweeping window as a starting point (Pinnacle), for which a significant TGU has been observed. The concept of CPS can be applied to DAO by choosing appropriate levels for each of the segments in DAO.

  7. Adhesion of denture tooth porcelain to heat-polymerized denture resin.

    PubMed

    Marchack, B W; Yu, Z; Zhao, X Y; White, S N

    1995-09-01

    Use of porcelain denture teeth may be desirable in many clinical situations, including implant-supported prostheses. However, lack of space because of frameworks often precludes the use of conventional retention by diatorics and pins. Adhesion of porcelain denture teeth to denture resin could also stiffen and possibly strengthen dentures and decrease stain ingress between porcelain teeth and resin denture bases. Unlike previous studies that investigated the bond between conventional feldspathic metal-ceramic porcelain and bis-GMA based composite resin, this study investigated adhesion of denture tooth porcelain to polymethyl methacrylate (PMMA). High-energy air abrasion, hydrofluoric acid etching, and the use of a general purpose bonding agent resulted in an improved bond strength of heat-cured denture PMMA bonded to denture tooth porcelain. Silane coating did not improve bond strengths, and conventional air abrasion was no more effective than polishing with 600-grit silicon carbide. Storage in water and artificial aging substantially decreased bond strengths. The strongest bond strengths were achieved by a high-energy-abrasion + etching + multi-purpose bonding-agent treatment, but a simpler etching + multiple-purpose bonding-agent treatment also produced reliable results. A laboratory technique was suggested. The role of surface treatment in the mechanism of adhesion was examined with scanning electron microscopy. High-energy abrasion produced a slightly more detailed initial topography than conventional air abrasion, but after etching, the high-energy topography became much more detailed. Surface topography alone did not account for all differences found. PMID:7473277

  8. 21 CFR 872.3530 - Mechanical denture cleaner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... mechanically agitating a denture cleansing solution. The device is intended to clean a denture by submersion in the agitating cleansing solution in the container. (b) Classification. Class I (general controls)....

  9. 21 CFR 872.3530 - Mechanical denture cleaner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... mechanically agitating a denture cleansing solution. The device is intended to clean a denture by submersion in the agitating cleansing solution in the container. (b) Classification. Class I (general controls)....

  10. 21 CFR 872.3530 - Mechanical denture cleaner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... mechanically agitating a denture cleansing solution. The device is intended to clean a denture by submersion in the agitating cleansing solution in the container. (b) Classification. Class I (general controls)....

  11. 21 CFR 872.3530 - Mechanical denture cleaner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... mechanically agitating a denture cleansing solution. The device is intended to clean a denture by submersion in the agitating cleansing solution in the container. (b) Classification. Class I (general controls)....

  12. Complete denture biofilm after brushing with specific denture paste, neutral soap and artificial saliva.

    PubMed

    Paranhos, Helena de Freitas Oliveira; Salles, Antônio Eduardo Sparça; Macedo, Leandro Dorigan de; Silva-Lovato, Cláudia Helena da; Pagnano, Valéria Oliveira; Watanabe, Evandro

    2013-01-01

    This study compared the levels of biofilm in maxillary and mandibular complete dentures and evaluated the number of colony-forming units (cfu) of yeasts, after using auxiliary brushing agents and artificial saliva. Twenty-three denture wearers with hyposalivation and xerostomia were instructed to brush the dentures 3 times a day during 3 weeks with the following products: Corega Brite denture dentifrice, neutral liquid soap, Corega Brite combined with Oral Balance (artificial saliva) or tap water. For biofilm quantification, the internal surfaces of the dentures were disclosed, photographed and measured using a software. For microbiological analysis, the biofilm was scrapped off, and the harvested material was diluted, sown in CHROMagar™ Candida and incubated at 37°C for 48 h. Data were analyzed statistically by two-way ANOVA and Tukey's test (α=0.05). Mandibular dentures presented a mean biofilm percentage (µ=26.90 ± 21.10) significantly greater than the maxillary ones (µ=18.0 ± 15.0) (p<0.05). Brushing using Corega Brite combined with Oral Balance (µ=15.87 ± 18.47) was more effective (p<0.05) than using the denture dentifrice (µ=19.47 ± 17.24), neutral soap (µ=23.90 ± 18.63) or tap water (control; µ=32.50 ± 20.68). For the microbiological analysis, the chi-square test did not indicate significant difference between the hygiene products for either type of denture. The more frequently isolated species of yeasts were C. albicans, C. tropicalis and C. glabrata. In conclusion, mandibular dentures had more biofilm formation than maxillary ones. Denture brushing with Corega Brite dentifrice combined with the use of Oral Balance was the most effective method for reduction of biofilm levels, but the use of products did not show difference in yeast cfu counts. PMID:23657413

  13. Denture wearing during sleep doubles the risk of pneumonia in the very elderly.

    PubMed

    Iinuma, T; Arai, Y; Abe, Y; Takayama, M; Fukumoto, M; Fukui, Y; Iwase, T; Takebayashi, T; Hirose, N; Gionhaku, N; Komiyama, K

    2015-03-01

    Poor oral health and hygiene are increasingly recognized as major risk factors for pneumonia among the elderly. To identify modifiable oral health-related risk factors, we prospectively investigated associations between a constellation of oral health behaviors and incident pneumonia in the community-living very elderly (i.e., 85 years of age or older). At baseline, 524 randomly selected seniors (228 men and 296 women; mean age, 87.8 years) were examined for oral health status and oral hygiene behaviors as well as medical assessment, including blood chemistry analysis, and followed up annually until first hospitalization for or death from pneumonia. During a 3-year follow-up period, 48 events associated with pneumonia (20 deaths and 28 acute hospitalizations) were identified. Among 453 denture wearers, 186 (40.8%) who wore their dentures during sleep were at higher risk for pneumonia than those who removed their dentures at night (log rank P = 0.021). In a multivariate Cox model, both perceived swallowing difficulties and overnight denture wearing were independently associated with an approximately 2.3-fold higher risk of the incidence of pneumonia (for perceived swallowing difficulties, hazard ratio [HR], 2.31; and 95% confidence interval [CI], 1.11-4.82; and for denture wearing during sleep, HR, 2.38; and 95% CI, 1.25-4.56), which was comparable with the HR attributable to cognitive impairment (HR, 2.15; 95% CI, 1.06-4.34), history of stroke (HR, 2.46; 95% CI, 1.13-5.35), and respiratory disease (HR, 2.25; 95% CI, 1.20-4.23). In addition, those who wore dentures during sleep were more likely to have tongue and denture plaque, gum inflammation, positive culture for Candida albicans, and higher levels of circulating interleukin-6 as compared with their counterparts. This study provided empirical evidence that denture wearing during sleep is associated not only with oral inflammatory and microbial burden but also with incident pneumonia, suggesting potential

  14. 21 CFR 872.3530 - Mechanical denture cleaner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mechanical denture cleaner. 872.3530 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3530 Mechanical denture cleaner. (a) Identification. A mechanical denture cleaner is a device, usually AC-powered, that consists of a container...

  15. 21 CFR 872.3580 - Preformed gold denture tooth.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Preformed gold denture tooth. 872.3580 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3580 Preformed gold denture tooth. (a) Identification. A preformed gold denture tooth is a device composed of austenitic alloys or alloys containing...

  16. 21 CFR 872.3580 - Preformed gold denture tooth.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Preformed gold denture tooth. 872.3580 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3580 Preformed gold denture tooth. (a) Identification. A preformed gold denture tooth is a device composed of austenitic alloys or alloys containing...

  17. 21 CFR 872.3580 - Preformed gold denture tooth.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Preformed gold denture tooth. 872.3580 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3580 Preformed gold denture tooth. (a) Identification. A preformed gold denture tooth is a device composed of austenitic alloys or alloys containing...

  18. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hydrophilic resin coating for dentures. 872.3300... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device that consists of a...

  19. 21 CFR 872.3580 - Preformed gold denture tooth.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Preformed gold denture tooth. 872.3580 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3580 Preformed gold denture tooth. (a) Identification. A preformed gold denture tooth is a device composed of austenitic alloys or alloys containing...

  20. 21 CFR 872.3580 - Preformed gold denture tooth.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Preformed gold denture tooth. 872.3580 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3580 Preformed gold denture tooth. (a) Identification. A preformed gold denture tooth is a device composed of austenitic alloys or alloys containing...

  1. 21 CFR 872.3590 - Preformed plastic denture tooth.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Preformed plastic denture tooth. 872.3590 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3590 Preformed plastic denture tooth. (a) Identification. A preformed plastic denture tooth is a prefabricated device, composed of materials such as...

  2. 21 CFR 872.3590 - Preformed plastic denture tooth.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Preformed plastic denture tooth. 872.3590 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3590 Preformed plastic denture tooth. (a) Identification. A preformed plastic denture tooth is a prefabricated device, composed of materials such as...

  3. 21 CFR 872.3590 - Preformed plastic denture tooth.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Preformed plastic denture tooth. 872.3590 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3590 Preformed plastic denture tooth. (a) Identification. A preformed plastic denture tooth is a prefabricated device, composed of materials such as...

  4. 21 CFR 872.3590 - Preformed plastic denture tooth.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Preformed plastic denture tooth. 872.3590 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3590 Preformed plastic denture tooth. (a) Identification. A preformed plastic denture tooth is a prefabricated device, composed of materials such as...

  5. 21 CFR 872.3590 - Preformed plastic denture tooth.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Preformed plastic denture tooth. 872.3590 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3590 Preformed plastic denture tooth. (a) Identification. A preformed plastic denture tooth is a prefabricated device, composed of materials such as...

  6. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Hydrophilic resin coating for dentures. 872.3300... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device that consists of a...

  7. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Hydrophilic resin coating for dentures. 872.3300... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device that consists of a...

  8. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Hydrophilic resin coating for dentures. 872.3300... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device that consists of a...

  9. 21 CFR 872.3300 - Hydrophilic resin coating for dentures.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Hydrophilic resin coating for dentures. 872.3300... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3300 Hydrophilic resin coating for dentures. (a) Identification. A hydrophilic resin coating for dentures is a device that consists of a...

  10. Maximum bite force in elderly indigenous and non-indigenous denture wearers.

    PubMed

    Borie, Eduardo; Orsi, Iara A; Fuentes, Ramón; Beltrán, Víctor; Navarro, Pablo; Pareja, Felipe; Raimundo, Lariça B

    2014-01-01

    The aim of this study was to compare the measures of maximum bite force (MBF) in elderly edentulous indigenous (Mapuche) and non-indigenous individuals with new complete dentures at two different measuring times. A sample of 100 elderly subjects was divided into two groups: 50 indigenous and 50 non-indigenous, each including 25 females and 25 males. All individuals were totally edentulous, with new maxillary and mandibular removable complete dentures. Measurements were taken at the time of new prosthesis placement and after 1 month of use. Subjects were asked to perform with maximum effort three bites per side at maximum intercuspidation, with a rest time of 2 minutes in between. Statistics were analyzed with Student 's t-test. The MBF values were significantly higher in indigenous than non-indigenous subjects. Force after 1 month of wearing the new prosthesis was significantly higher than at the time of new prosthesis placement. No significant difference was found between sides. Elderly indigenous complete denture wearers had the greatest MBF values. Denture wearers were observed to undergo an adaptation process to the new prosthesis, with MBF increasing considerably after one month of use. PMID:25560689

  11. Flexural properties of denture base polymers.

    PubMed

    Ruyter, I E; Svendsen, S A

    1980-01-01

    Heat-polymerized denture base materials with the cross-linking agent 1,4-BDMA and with different amounts of the cross-linking agent EGDMA have similar flexural properties. At the relatively low loading rate of 2 N/minute all the heat-polymerized denture base materials investigated have better flexural properties than the autopolymerized pour- and dough-type materials. The autopolymerized materials with the cross-linking agent 1,4-BDMA have flexural properties intermediate to the heat-polymerized and the autopolymerized resins with the cross-linking agent EGDMA. The various autopolymerized resins behave differently, probably due to varying amounts of pendant methacrylate groups. Due to so-called solvent crazing, denture base polymers have poorer flexural properties when tested in water than in air. PMID:6927913

  12. CHIPPING FRACTURE RESISTANCE OF DENTURE TOOTH MATERIALS

    PubMed Central

    Quinn, G. D.; Giuseppetti, A. A.; Hoffman, K. H.

    2014-01-01

    Objective The applicability of the edge chipping method to denture tooth materials was assessed. These are softer materials than those usually tested by edge chipping. The edge chipping fracture resistances of polymethylmethacrylate (PMMA) based and two filled resin composite denture tooth materials were compared. Methods An edge chipping machine was used to chip rectangular blocks and flattened anterior denture teeth. Force versus edge distance data were collected over a broad range of forces and distances. Between 20 and 65 chips were made per condition depending upon the material, the scatter, and the indenter type. Different indenter types were used including Rockwell C, sharp conical 120°, Knoop, and Vickers. The edge toughness, Te, was evaluated for different indenter types. Results The edge chipping data collected on the blocks matched the data collected from flattened teeth. High scatter, particularly at large distances and loads, meant that many tests (up to 64) were necessary to compare the denture tooth materials and to ascertain the appropriate data trends. A linear force – distance trend analysis was adequate for comparing these materials. A power law trend might be more appropriate, but the large scatter obscured the definitive determination of the precise trend. Different indenters produce different linear trends, with the ranking of: sharp conical 120°, Rockwell C, and Knoop, from lowest to highest edge toughness. Vickers indenter data were extremely scattered and a sensible trend could not be obtained. Edge toughness was inversely correlated to hardness. Significance Edge chipping data collected either from simple laboratory scale test blocks or from actual denture teeth may be used to evaluate denture materials. The edge chipping method’s applicability has been extended to another class of restorative materials. PMID:24674342

  13. Denture-Related Biomechanical Factors for Fixed Partial Dentures Retained on Short Dental Implants.

    PubMed

    Pommer, Bernhard; Hingsammer, Lukas; Haas, Robert; Mailath-Pokorny, Georg; Busenlechner, Dieter; Watzek, Georg; Fürhauser, Rudolf

    2015-01-01

    Prosthodontically driven biomechanical considerations are essential for longterm successful outcomes in dental implant therapy. Correct protocols seek to preclude potential consequences associated with functional and parafunctional occlusal overload such as screw loosening, component fracture, compromised marginal bone maintenance, and the integrity of the induced osseointegration response. Other concerns also need to be addressed, more especially when other implants are selected, for example: bridge insertion torque (BIT) in cases of immediate loading, cantilever length-anteroposterior spread ratio (CL-AP), overall crown-to-implant ratio (oCIR), total bone-to-implant surface area (tBICA), and the status of the opposing dentition. In spite of promising clinical results, evidence-based clinical protocols demand that such biomechanical limits still need to be determined. PMID:26218027

  14. Completely digital approach to fabricating a crown under an existing partial removable dental prosthesis by using an intraoral digital scanner in a single appointment.

    PubMed

    Lee, Ju-Hyoung

    2016-06-01

    Retrofitting a crown to an existing partial removable dental prosthesis (PRDP) is difficult, labor intensive, and time consuming. This article presents an alternative technique for fabricating a crown under an existing PRDP by using an intraoral digital scanner and computer-assisted design and computer-aided manufacturing (CAD/CAM) technology. This technique involves less human error and provides a well-fitting restoration. PMID:26809222

  15. Prosthetic rehabilitation with collapsible hybrid acrylic resin and permanent silicone soft liner complete denture of a patient with scleroderma-induced microstomia.

    PubMed

    Singh, Kunwarjeet; Gupta, Nidhi; Gupta, Ridhimaa; Abrahm, Dex

    2014-07-01

    Scleroderma is an autoimmune multisystem rheumatic condition characterized by fibrosis of connective tissues of the body, resulting in hardening and impairment of the function of different organs. Deposition of collagen fibers in peri-oral tissues causes loss of elasticity and increased tissue stiffness, resulting in restricted mouth opening. A maximal oral opening smaller than the size of a complete denture can make prosthetic treatment challenging. Patients with microstomia who must wear removable dental prostheses (RDPs) often face the difficulty of being unable to insert or remove a conventional RDP. A sectional-collapsible denture is indicated for the prosthetic management of these patients, but reduced manual dexterity often makes intraoral manipulation of the prosthesis difficult. A single collapsible complete denture is a better choice for functional rehabilitation of these patients. This clinical report describes in detail the prosthodontic management of a maxillary edentulous patient with restricted mouth opening induced by scleroderma with a single collapsible removable complete denture fabricated with heat-polymerized silicone soft liner and heat-cured acrylic resin. The preliminary and secondary impressions were made with moldable aluminum trays by using putty and light-body poly(vinyl siloxane) elastomeric impression material. The collapsed denture can be easily inserted and removed by the patient and also provides adequate function in the mouth. PMID:24417310

  16. Training Plates: A Solution for Patients Unable to Tolerate a Removable Prosthesis.

    PubMed

    Laverty, Dominic P; Damien Walmsley, A

    2016-03-01

    Dealing with patients who are unable to tolerate dentures can present a challenge to the general dental practitioner (GDP). Careful assessment of patients and their dentures will identify any causes of the intolerance to dentures. Training plates are a useful technique that can be used to allow patients to become accustomed to removable prosthesis but will inevitably lengthen the treatment process. CPD/Clinical Relevance: Training plates offer a possible solution to general dental practitioners who treat patients who are struggling to tolerate dentures. PMID:27188131

  17. Patients' satisfaction and maintenance of fixed partial denture

    PubMed Central

    Geiballa, Ghada Hassan; Abubakr, Neamat Hassan; Ibrahim, Yahia Eltayib

    2016-01-01

    Objectives: The aims of this study were to evaluate patient satisfaction with fixed prosthesis following placement and to assess the oral health and oral hygiene practices awareness by survey questionnaire. Materials and Methods: One hundred and ninety-two questionnaires were filled by patients wearing fixed prosthesis; the questionnaire included the subjective perception of treatment with fixed prosthesis, patients' perception of clinical outcome, regarding esthetics, masticatory function, speech, and together patient's attitude toward oral hygiene measures. Results: Results showed that 84% of the patients were satisfied with their fixed prosthesis, while only 46.4% of patients were satisfied with the chewing ability. In concern, with esthetic outcome, 80% of patients showed that they were satisfied with the esthetic. The results showed that a high significantly number of patients did not use any form of interdental aids' to clean their fixed prosthesis (94%). The main reason for not using any dental aids' (91.1%) was a lack of post fixed prosthodontics instructions and not been informed by the dentist. Conclusion: High percentages of patients were satisfied with their fixed prosthesis. The most important finding of this study was that majority of patients showed a lack of knowledge regarding post fixed prosthodontics instructions and the significance of maintenance of fixed prosthesis using dental aids'. Of particular concern was the majority of dentists did not pay attention to the post treatment instructions concerning the maintenance of fixed prosthesis. PMID:27095906

  18. Stress analysis of a fixed implant-supported denture by the finite element method (FEM) when varying the number of teeth used as abutments

    PubMed Central

    LANZA, Marcos Daniel Septímio; SERAIDARIAN, Paulo Isaías; JANSEN, Wellington Correa; LANZA, Marcos Dias

    2011-01-01

    Objectives In some clinical situations, dentists come across partially edentulous patients, and it might be necessary to connect teeth to implants. The aim of this study was to evaluate a metal-ceramic fixed tooth/implant-supported denture with a straight segment, located in the posterior region of the maxilla, when varying the number of teeth used as abutments. Materials and Methods A three-element fixed denture composed of one tooth and one implant (Model 1), and a four-element fixed denture composed of two teeth and one implant (Model 2) were modeled. A 100 N load was applied, distributed uniformly on the entire set, simulating functional mastication, for further analysis of the SEQV (Von Mises) principal stresses, which were compared with the flow limit of the materials. Results In a quantitative analysis, it may be observed that in the denture with one tooth, the maximum SEQV stress was 47.84 MPa, whereas for the denture with two teeth the maximum SEQV stress was 35.82 MPa, both located in the region between the pontic and the tooth. Conclusion Lower stresses were observed in the denture with an additional tooth. Based on the flow limit of the materials, porcelain showed values below the limit of functional mastication. PMID:22231003

  19. 21 CFR 872.3420 - Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... polyacrylamide polymer denture adhesive. 872.3420 Section 872.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION....3420 Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive. (a) Identification. A carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive is a...

  20. 21 CFR 872.3420 - Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... polyacrylamide polymer denture adhesive. 872.3420 Section 872.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION....3420 Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive. (a) Identification. A carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive is a...

  1. 21 CFR 872.3420 - Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... polyacrylamide polymer denture adhesive. 872.3420 Section 872.3420 Food and Drugs FOOD AND DRUG ADMINISTRATION....3420 Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive. (a) Identification. A carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive is a...

  2. 21 CFR 872.3450 - Ethylene oxide homopolymer and/or karaya denture adhesive.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... to the base of a denture before the denture is inserted in a patient's mouth to improve denture... the mouth. The device is intended to be discarded following 1 day's use. The class I device is...

  3. Evaluating denture cleanliness of patients in a regional dental hospital.

    PubMed

    Mylonas, P; Attrill, D C; Walmsley, A D

    2016-08-12

    Aims To evaluate the quality of clinical record keeping and determine quality of denture cleanliness; record baseline denture cleanliness for 60 patients; introduce denture hygiene instruction (DHI); and then re-assess the patients for improvement and enhanced record keeping.Methods Analysis of patients' denture hygiene instruction record keeping (n = 60) was undertaken retrospectively. The Denture Cleanliness Index (DCI) was utilised to assess denture cleanliness (best score 0, worst score 4). Baseline DCI scores were taken and individual DHI was delivered. After one month, patients were reviewed and scored, with record keeping quality analysed.Results At baseline, 11.7% (n = 7) of patients had DCI scores of ≤2, improving to 93.8% (n = 45) after one month, demonstrating short-term improvement in denture cleanliness. Only 63% (n = 38) of patients had evidence of a record of DHI within their notes at baseline, improving to 100% at recall.Conclusions New patient information leaflet and clinical guidelines on denture hygiene have been written and implemented. The results of this study suggest that this may be a relatively straightforward method to achieve a short-term improvement in denture cleanliness. The implementation of a DCI score is helpful in allowing patients to improve denture hygiene and its wider use is supported. PMID:27514347

  4. Dentures - Multiple Languages: MedlinePlus

    MedlinePlus

    ... Việt) Dentures English Hàm răng giả - Tiếng Việt (Vietnamese) PDF California Dental Association Characters not displaying correctly on this page? See language display issues . Return to the MedlinePlus Health Information ...

  5. [Superplastic forming of titanium alloy denture base].

    PubMed

    Okuno, O; Nakano, T; Hamanaka, H; Miura, I; Ito, M; Ai, M; Okada, M

    1989-03-01

    Ti-6Al-4V alloy has both excellent biocompatibility and superior mechanical properties. This Ti-6Al-4V can be deformed greatly and easily at the superplastic temperature of 800 degrees C to 900 degrees C. The superplastic forming of Ti-6Al-4V was made to apply to fabrication of denture base. Almost the same procedure as for dental casting mold was employed in producing the superplastic forming die by the improved phosphate bonded investment. In the pressure vessel of heat resistant alloy, Ti-6Al-4V plate was formed superplastically on the die by argon gas pressure at 850 degrees C. The fit of superplactic forming Ti-6Al-4V denture base was better than that of casting Co-Cr alloy denture bases. The Ti-6Al-4V alloy might react a little with the die. Because micro Vikers hardness of the cross-section did not go up too much near the surfaces. Even just after being formed, the surfaces were much smoother than that of Co-Cr alloy casting. The tensile strength and yield strength of superplastic forming Ti-6Al-4V were higher than those of Co-Cr castings. The elongation was about 10%. These results show that superplastic forming of Ti-6Al-4V would be suitable for a denture base. PMID:2603084

  6. Photoelastic stress analysis in screwed and cemented implant-supported dentures with external hexagon implants.

    PubMed

    Pellizzer, Eduardo Piza; Tonella, Bianca Piccolotto; Ferraço, Renato; Falcón-Antenucci, Rosse Mary; de Carvalho, Paulo Sérgio Perri; Alves-Rezende, Maria Cristina Rosifini

    2010-07-01

    The aim of this study was to assess the stress distribution of the retention systems (screwed and cemented) for implant-supported fixed partial dentures by means of photoelastic method. Two models were made of photoelastic resin PL-2 with 2 implants (phi = 4.00 x 10 mm) located in the second premolar and molar region in each photoelastic model, varying the retention system (screwed and cemented). The implant-supported fixed partial dentures were standardized and made of Ni-Cr alloy. Axial and oblique (45 degrees) forces of 100 N were applied on the occlusal surface by means of a Universal Testing Machine (EMIC-DL 3000; São José dos Pinhais, Paraná, Brazil). The results were observed and photographed in the field of a circular polariscope and qualitatively analyzed with the aid of computer software (Adobe Photoshop, San Jose, CA). The screw retention system presented the highest number of fringes when the loads were applied on the premolar, pontic, and molar and showed this behavior in all load applications, under axial and oblique loads. It was concluded that there was a better stress distribution and lower magnitude of stress on the cemented implant-supported dentures, under axial and oblique loads. Oblique load caused an increase in stress concentrations in all the models. PMID:20613577

  7. Fate of hormones and pharmaceuticals during combined anaerobic treatment and nitrogen removal by partial nitritation-anammox in vacuum collected black water.

    PubMed

    de Graaff, M S; Vieno, N M; Kujawa-Roeleveld, K; Zeeman, G; Temmink, H; Buisman, C J N

    2011-01-01

    Vacuum collected black (toilet) water contains hormones and pharmaceuticals in relatively high concentrations (μg/L to mg/L range) and separate specific treatment has the potential of minimizing their discharge to surface waters. In this study, the fate of estrogens (natural and synthetical hormones) and pharmaceuticals (paracetamol, metoprolol, propranolol, cetirizine, doxycycline, tetracycline, ciprofloxacin, trimethoprim, carbamazepine, ibuprofen and diclofenac) in the anaerobic treatment of vacuum collected black water followed by nitrogen removal by partial nitritation-anammox was investigated. A new analytical method was developed to detect the presence of several compounds in the complex matrix of concentrated black water. Detected concentrations in black water ranged from 1.1 μg/L for carbamazepine to >1000 μg/L for paracetamol. Anaerobic treatment was only suitable to remove the majority of paracetamol (>90%). Metoprolol was partly removed (67%) during aerobic treatment. Deconjugation could have affected the removal efficiency of ibuprofen as concentrations even increased during anaerobic treatment and only after the anammox treatment 77% of ibuprofen was removed. The presence of persistent micro-pollutants (diclofenac, carbamazepine and cetirizine), which are not susceptible for biodegradation, makes the application of advanced physical and chemical treatment unavoidable. PMID:20832097

  8. Mastication Improvement After Partial Implant-supported Prosthesis Use

    PubMed Central

    Gonçalves, T.M.S.V.; Campos, C.H.; Gonçalves, G.M.; de Moraes, M.; Rodrigues Garcia, R.C.M.

    2013-01-01

    Partially edentulous patients may be rehabilitated by the placement of removable dental prostheses, implant-supported removable dental prostheses, or partial implant fixed dental prostheses. However, it is unclear the impact of each prosthesis type over the masticatory aspects, which represents the objective of this paired clinical trial. Twelve patients sequentially received and used each of these 3 prosthesis types for 2 months, after which maximum bite force was assessed by a strain sensor and food comminution index was determined with the sieving method. Masseter and temporal muscle thicknesses during rest and maximal clenching were also evaluated by ultrasonography. Each maxillary arch received a new complete denture that was used throughout the study. Data were analyzed by analysis of variance for repeated measures, followed by the Tukey test (p < .05). Maximum bite force and food comminution index increased (p < .0001) after implant-supported dental prosthesis and implant fixed dental prosthesis use, with the higher improvement found after the latter’s use. Regardless of implant-retained prosthesis type, masseter muscle thickness during maximal clenching also increased (p < .05) after implant insertion. Partial implant-supported prostheses significantly improved masseter muscle thickness and mastication, and the magnitude of this effect was related to prosthesis type (International Clinical Trial Registration RBR-9J26XD). PMID:24158344

  9. Different Occlusal Schemes in a Persistent Protruding Complete Denture Wearer.

    PubMed

    Iegami, Carolina Mayumi; Lopes, Danilo de Melo; Nakamae, Atlas Edson Moleros; Uehara, Priscila Nakasone; Tamaki, Regina

    2016-01-01

    Different types of artificial teeth and occlusal designs can be used in complete dentures. Bilateral balanced occlusion, lingualized occlusion, canine guidance, and monoplane are the main occlusal designs; however there is no agreement on which tooth arrangement is ideal for achieving success in complete dentures. This report presents an alternative for persistent involuntary protruding complete denture wearers through the use of artificial teeth with higher cusps. Due to an old and worn pair of complete dentures, the patient had the habit of protruding. New dentures were made with Biotone artificial teeth and in the trial session, the patient would still protrude. A new set was made with Premium artificial teeth, which present higher cusps. With these dentures, the involuntary protrusion did not occur. From the delivery to the follow-up sessions, the patient stopped protruding. PMID:27069698

  10. Different Occlusal Schemes in a Persistent Protruding Complete Denture Wearer

    PubMed Central

    Iegami, Carolina Mayumi; Lopes, Danilo de Melo; Nakamae, Atlas Edson Moleros; Uehara, Priscila Nakasone; Tamaki, Regina

    2016-01-01

    Different types of artificial teeth and occlusal designs can be used in complete dentures. Bilateral balanced occlusion, lingualized occlusion, canine guidance, and monoplane are the main occlusal designs; however there is no agreement on which tooth arrangement is ideal for achieving success in complete dentures. This report presents an alternative for persistent involuntary protruding complete denture wearers through the use of artificial teeth with higher cusps. Due to an old and worn pair of complete dentures, the patient had the habit of protruding. New dentures were made with Biotone artificial teeth and in the trial session, the patient would still protrude. A new set was made with Premium artificial teeth, which present higher cusps. With these dentures, the involuntary protrusion did not occur. From the delivery to the follow-up sessions, the patient stopped protruding. PMID:27069698

  11. Effects of tooth loss and denture wear on tongue-tip motion in elderly dentulous and edentulous people.

    PubMed

    Yoshikawa, M; Yoshida, M; Nagasaki, T; Tanimoto, K; Tsuga, K; Akagawa, Y

    2008-12-01

    The purpose of this study was to clarify quantitatively the differences in tongue-tip motion among the dentulous elderly people and also among the elderly edentulous, both with and without their dentures and, to identify the influence of tooth loss and denture wear on tongue-tip motion. Fourteen young dentulous people, 12 elderly dentulous people and 13 elderly edentulous people participated in this study. Subjects were asked to swallow a 10 mL barium sulfate solution three times. The elderly edentulous people were asked to swallow the solution while wearing dentures and with dentures removed. Functional swallowing was recorded on cine-film with a digital subtraction angiography system. Lateral cinefluorography images were obtained from seated subjects. Using a cine-projector, the movements of the tongue surface were traced as dots and lines frame by frame on a single tracing sheet within a definite period of time from the beginning of the oral phase to the end of the pharyngeal phase. With counting the number of 'trajectories' of tongue-tip motion, tongue movements were classified as 'stable' and 'hyperactive' types. The results was that significantly more 'hyperactive' type subjects were found among the elderly edentulous who were not wearing dentures (12 of 13) compared with the dentulous young (1 of 14), the elderly dentulous (1 of 13) or the elderly edentulous wearing dentures (1 of 13) (P < 0.001). The tongue-tip motion for the 'hyperactive' type was very complex and the tongue-tip anchoring against the palate was always instable. PMID:19090906

  12. Fabrication of a metal-ceramic crown to fit an existing partial removable dental prosthesis using ceramic pressed to metal technique: a clinical report

    PubMed Central

    Seo, Jae-Min

    2014-01-01

    Fabricating a crown to retrofit an existing abutment tooth for a partial removable dental prosthesis (PRDP) is one of the most time-consuming and labor-intensive clinical procedures. In particular, when the patient is concerned with esthetic aspects of restoration, the task of fabricating becomes more daunting. Many techniques for the fabrication of all-metallic or metal-ceramic crowns have been discussed in the literature. This article was aimed to describe a simple fabrication method in which a retrofitting crown was fabricated for a precise fit using a ceramic-pressed-to-metal system. PMID:25006389

  13. Denture bar-coding: An innovative technique in forensic dentistry

    PubMed Central

    Dineshshankar, Janardhanam; Venkateshwaran, Rajendran; Vidhya, J.; Anuradha, R.; Mary, Gold Pealin; Pradeep, R.; Senthileagappan, A. R.

    2015-01-01

    Denture markers play an important role in forensic odontology and also in identifying a person. A number of methods are there for identifying dentures from a less expensive technique to a more expensive technique. Out of different denture markers, the bar-coding system is a way of collecting data from the mobile. Even a huge amount of data can be stored in that. It can be easily incorporated during acrylization of the denture and thus could be helpful in identification. This article reviews the strengths of bar-coding and how easily it can be used in the routine procedure. PMID:26538876

  14. Controlling fungal biofilms with functional drug delivery denture biomaterials.

    PubMed

    Wen, Jianchuan; Jiang, Fuguang; Yeh, Chih-Ko; Sun, Yuyu

    2016-04-01

    Candida-associated denture stomatitis (CADS), caused by colonization and biofilm-formation of Candida species on denture surfaces, is a significant clinical concern. We show here that modification of conventional denture materials with functional groups can significantly increase drug binding capacity and control drug release rate of the resulting denture materials for potentially managing CADS. In our approach, poly(methyl methacrylate) (PMMA)-based denture resins were surface grafted with three kinds of polymers, poly(1-vinyl-2-pyrrolidinone) (PNVP), poly(methacrylic acid) (PMAA), and poly(2-hydroxyethyl methacrylate) (PHEMA), through plasma-initiated grafting polymerization. With a grafting yield as low as 2 wt%, the three classes of new functionalized denture materials showed significantly higher drug binding capacities toward miconazole, a widely used antifungal drug, than the original PMMA denture resin control, leading to sustained drug release and potent biofilm-controlling effects against Candida. Among the three classes of functionalized denture materials, PNVP-grafted resin provided the highest miconazole binding capability and the most powerful antifungal and biofilm-controlling activities. Drug binding mechanisms were studied. These results demonstrated the importance of specific interactions between drug molecules and functional groups on biomaterials, shedding lights on future design of CADS-managing denture materials and other related devices for controlled drug delivery. PMID:26731194

  15. Use of cystourethroscopy to remove an indwelling double-J ureteral stent 6 years following simultaneous radical sigmoid colon cancer and partial bladder resection: A case report

    PubMed Central

    GU, YAN; ZHANG, JING; WANG, GUOZENG

    2016-01-01

    Ureteral stents are widely used to ensure good urinary drainage and to relieve obstruction, pain and infection during urologic procedures. However, long-term indwelling ureteral stents can cause various complications, such as encrustation, hematuria and infection. Here, the case of an 88-year-old man who had undergone simultaneous radical resection of sigmoid colon cancer and partial resection of the bladder 6 years prior is presented. The patient complained of urinary frequency and urgency, dysuria and intermittent fever. A kidney ureter bladder X-ray examination revealed the presence of an entire coiled double-J stent with calculi from the kidney to the bladder. A computed tomography scan revealed mild hydronephrosis of the left kidney and one J end of the stent in the bladder. The stent was removed successfully by cystourethroscopy and holmium laser lithotripsy. This report describes the clinical experience of the removal of a long-term stent by endoscopic manipulation. PMID:27313675

  16. Corneal haze and visual outcome after collagen crosslinking for keratoconus: A comparison between total epithelium off and partial epithelial removal methods

    PubMed Central

    Razmjoo, Hasan; Rahimi, Behrooz; Kharraji, Mona; Koosha, Nima; Peyman, Alireza

    2014-01-01

    Background: Keratoconus is an asymmetric, bilateral, progressive noninflammatory ectasia of the cornea that affects approximately 1 in 2000 of the general population. This may cause a significant negative impact on quality of life. Corneal collagen crosslinking (CXL) is one of the recently introduced methods that have been used to decrease the progression of keratoconus, in particular, as well as other corneal-thinning processes. Materials and Methods: A total of 44 keratoconic eyes of 22 patients were enrolled in this randomized prospective study, after obtaining informed consent. In the first group, the corneal epithelium were totally removed and in the second group, the central 3 mm of epithelium was kept intact and partial removal was performed. After collagen crosslinking in both groups, comprehensive ophthalmologic examination was performed on all patients before and 6 months after the surgery. This article is registered at www.clinicaltrial.gov with registration number NCT01809977. Results: The difference between the two groups was not statistically significant regarding postoperative corneal haziness, refraction, and visual acuity (P > 0.05). However, comparison of pre- and postoperative parameters within each group revealed that total removal of the cornea has resulted in significant improvement of K-max (P value: 0.01) and Q-value (P value: 0.009); while eyes in partial removal group had better improvement of corrected vision (P value: 0.006). Both methods had significant and similar increase in optical corneal density (P < 0.0001). Conclusion: In our study, keeping the central corneal epithelium intact was not beneficial for decreasing corneal haziness, however, this method caused better improvement in corrected vision. Total epithelium off technique resulted in better improvement of K-max and Q-value. PMID:25538907

  17. The feasibility of an up-flow partially aerated biological filter (U-PABF) for nitrogen and COD removal from domestic wastewater.

    PubMed

    Tao, Chen; Peng, Tong; Feng, Chuanping; Chen, Nan; Hu, Qili; Hao, Chunbo

    2016-10-01

    An up-flow partially aerated biological filter (U-PABF) was developed to study the removal of nitrogen and chemical oxygen demand (COD) from synthetic domestic wastewater. The removal of NH4(+)-N was primarily attributed to adsorption in the zeolite U-PABF and to bioprocesses in the ceramic U-PABF. When the hydraulic retention time (HRT) was 5.2h, the ceramic U-PABF achieved a good performance and the NH4(+)-N, total nitrogen (TN), and COD removal efficiency reached 99.08±8.79%, 72.83±0.68%, and 89.38±1.04%, respectively. The analysis of NH4(+)-N, NO3(-)-N, NO2(-)-N, and TN at different depths revealed the simultaneous existence of nitrification-denitrification, and anaerobic ammonium oxidation (anammox) in ceramic U-PABF. Illumina pyrosequencing confirmed the existence of Planctomycetes, which are responsible for anammox. The results indicated that the nitrification-denitrification and anammox all contributed to the high removal of NH4(+)-N, TN, and COD in the U-PABF. PMID:27372011

  18. Fatigue Life of Cast Titanium Alloys Under Simulated Denture Framework Displacements

    NASA Astrophysics Data System (ADS)

    Koike, Mari; Chan, Kwai S.; Hummel, Susan K.; Mason, Robert L.; Okabe, Toru

    2013-02-01

    The objective of the study was to evaluate the hypothesis that the mechanical properties and fatigue behavior of removable partial dentures (RPD) made from cast titanium alloys can be improved by alloying with low-cost, low-melting elements such as Cu, Al, and Fe using commercially pure Ti (CP-Ti) and Ti-6Al-4V as controls. RPD specimens in the form of rest-shaped, clasp, rectangular-shaped specimens and round-bar tensile specimens were cast using an experimental Ti-5Al-5Cu alloy, Ti-5Al-1Fe, and Ti-1Fe in an Al2O3-based investment with a centrifugal-casting machine. The mechanical properties of the alloys were determined by performing tensile tests under a controlled displacement rate. The fatigue life of the RPD specimens was tested by the three-point bending in an MTS testing machine under a cyclic displacement of 0.5 mm. Fatigue tests were performed at 10 Hz at ambient temperature until the specimens failed into two pieces. The tensile data were statistically analyzed using one-way ANOVA (α = 0.05) and the fatigue life data were analyzed using the Kaplan-Meier survival analysis (α = 0.05). The experimental Ti-5Al-5Cu alloy showed a significantly higher average fatigue life than that of either CP-Ti or Ti-5Al-1Fe alloy ( p < 0.05). SEM fractography showed that the fatigue cracks initiated from surface grains, surface pores, or hard particles in surface grains instead of the internal casting pores. Among the alloys tested, the Ti-5Al-5Cu alloy exhibited favorable results in fabricating dental appliances with an excellent fatigue behavior compared with other commercial alloys.

  19. [Prosthetic rehabilitation of partially edentulous patients: fixed - removable - combined? Metal - ceramics - all - ceramics? Implants? Anything goes! Part 2: two case studies represent the fixed, respectively the combined fixed-removable prosthetic restoration by utilization of implants].

    PubMed

    Schnabl, Dagmar

    2015-01-01

    The prosthetic rehabilitation of two partially edentulous patients is presented: one Patient was restored by permanent crowns and bridges attached to natural teeth and to implants, the second was treated by crowns attached to natural teeth and removable implant- supported prostheses. Depending on esthetic requirements and the localization of preparation margins all- or metal-ceramics were used for single crowns, metal-ceramics was used for bridges. In general, a well coordinated cooperation of dentist, surgeon and dental technician in treatment planning and realization is required for a successful prosthetic rehabilitation. PMID:25734274

  20. Surface Passivation of ZrO2 Artificial Dentures by Magnetized Coaxial Plasma deposition

    NASA Astrophysics Data System (ADS)

    Arai, Soya; Kurumi, Satoshi; Matsuda, Ken-Ichi; Suzuki, Kaoru; Hara, Katsuya; Kato, Tatsuya; Asai, Tomohiko; Hirose, Hideharu; Masutani, Shigeyuki; Nihon University Team

    2015-09-01

    Recent growth and fabrication technologies for functional materials have been greatly contributed to drastic development of oral surgery field. Zirconia based ceramics is expected to utilize artificial dentures because these ceramics have good biocompatibility, high hardness and aesthetic attractively. However, to apply these ceramics to artificial dentures, this denture is removed from a dental plate because of weakly bond. For improving this problem, synthesis an Al passivation-layer on the ceramics for bonding with these dental items is suitable. In order to deposit the passivation layer, we focused on a magnetized coaxial plasma deposition (MCPD). The greatest characteristic of MCPD is that high-melting point metal can be deposited on various substrates. Additionally, adhesion force between substrate and films deposited by the MCPD is superior to it of general deposition methods. In this study, we have reported on the growth techniques of Al films on ZrO2 for contributing to oral surgery by the MCPD. Surface of deposited films shows there were some droplets and thickness of it is about 200 nm. Thickness is increased to 500 nm with increasing applied voltage.

  1. Complete denture covering mandibular tori using three base materials: a case report.

    PubMed

    Abrams, S

    2000-10-01

    The torus mandibularis presents many challenges when fabricating a complete denture. The mucosa tends to be thin and will not tolerate normal occlusal loads on a denture. Large mandibular tori can prevent complete seating of impression trays and denture. To address this problem, we fabricated a new mandibular complete denture incorporating a combination of soft acrylic flanges and liners. PMID:11070628

  2. Holographic Measuring Of Deformations In Complete Upper Dentures

    NASA Astrophysics Data System (ADS)

    Dirtoft, Ingegerd; Abramson, Nils; Sandstrom, Unto

    1980-05-01

    A clinically useful method using hologram interferometry to measure deformations in upper complete dentures is described. Real-time and sandwich holography have been used both to measure deformation as well as to insure proper repositioning of the dentures on the mea-surement stand.

  3. A Clinical Evaluation Denture Adhesives Used by Patients With Xerostomia

    PubMed Central

    Bogucki, Zdzislaw A.; Napadlek, Piotr; Dabrowa, Tomasz

    2015-01-01

    Abstract The purpose of study was to analyze the participants’ opinions concerning the effectiveness of 6 denture adhesives (DA). The study group included 60 participants. Criteria for selecting the patients were as follows: reduced retention and stabilization of maxillary complete dentures and xerostomia. These features were evaluated on basis of clinical examination and standard sialometry tests (u-SFR). Retention of maxillary dentures was scored by modified Kapur index before application of DA. All participants were divided randomly into 6 groups regarding the use of the 6 DA during a 6-month period. After this time, participants completed an HRQL questionnaire. DA noticeably improved retention and stabilization of maxillary complete dentures. DA in the glue form had the best retention effectiveness in participants with xerostomia. These materials are difficult to clean from the denture base. The data are presented in tables and figures. The results of the study collected positive influence of adhesives on retention of dentures in xerostomia patients. The cleaning dentures and denture bearing tissues was difficult. DA help in the use of prostheses, but it is also necessary for the treatment of the causes and symptoms of xerostomia. PMID:25700320

  4. 21 CFR 872.3570 - OTC denture repair kit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false OTC denture repair kit. 872.3570 Section 872.3570 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3570 OTC denture repair kit. (a)...

  5. 21 CFR 872.3570 - OTC denture repair kit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false OTC denture repair kit. 872.3570 Section 872.3570 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3570 OTC denture repair kit. (a)...

  6. 21 CFR 872.3560 - OTC denture reliner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false OTC denture reliner. 872.3560 Section 872.3560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3560 OTC denture reliner. (a) Identification....

  7. 21 CFR 872.3570 - OTC denture repair kit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false OTC denture repair kit. 872.3570 Section 872.3570 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3570 OTC denture repair kit. (a)...

  8. 21 CFR 872.3560 - OTC denture reliner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false OTC denture reliner. 872.3560 Section 872.3560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3560 OTC denture reliner. (a) Identification....

  9. 21 CFR 872.3560 - OTC denture reliner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false OTC denture reliner. 872.3560 Section 872.3560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3560 OTC denture reliner. (a) Identification....

  10. 21 CFR 872.3560 - OTC denture reliner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false OTC denture reliner. 872.3560 Section 872.3560 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3560 OTC denture reliner. (a) Identification....

  11. 21 CFR 872.3570 - OTC denture repair kit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false OTC denture repair kit. 872.3570 Section 872.3570 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3570 OTC denture repair kit. (a)...

  12. Start-up and bacterial communities of single-stage nitrogen removal using anammox and partial nitritation (SNAP) for treatment of high strength ammonia wastewater.

    PubMed

    Zhang, Jianbing; Zhou, Jian; Han, Yi; Zhang, Xiaoguang

    2014-10-01

    In this study, a lab-scale sequencing batch biofilm reactor (SBBR) was used to start up the single-stage nitrogen removal system using anammox and partial nitritation (SNAP) process seeding from surplus activated sludge. The volumetric nitrogen loading rate (vNLR) was firstly 0.075 kg N m(-3) d(-1) and then gradually increased to 0.60 kg N m(-3) d(-1). A maximal total nitrogen (TN) removal rate of 0.54 kg N m(-3) d(-1) was achieved by the SNAP process after 132 days operation with NH4(+)-N and TN removal efficiency of 99.4% and 90.5%, respectively. This reactor may have applications for the SNAP process treating high strength ammonia wastewater. And dewatered surplus activated sludge was recommended as the seed sludge for engineering applications. The dominant bacterial strains were Xanthomonas campestris, Nitrosomonas europaea and Ignavibacterium album, corresponding to the percentage of 24%, 22% and 20%, respectively, based on the 16S rDNA amplicon pyrosequencing of the SNAP sludge. PMID:25105271

  13. Rapid adsorptive removal of toxic Pb(2+) ion from aqueous solution using recyclable, biodegradable nanocomposite derived from templated partially hydrolyzed xanthan gum and nanosilica.

    PubMed

    Ghorai, Soumitra; Sarkar, Amit Kumar; Pal, Sagar

    2014-10-01

    This work studied the application of a novel biodegradable nanocomposite based on partially hydrolyzed polyacrylamide grafted xanthan gum and nanosilica (h-XG/SiO2) towards efficient and rapid removal of toxic Pb(2+) ions from aqueous environment. The uptake ability of Pb(2+) using h-XG/SiO2 has been studied in batch adsorption experiments with variation of adsorption parameters. The excellent removal rate (99.54% adsorption within 25min) and superior adsorption capacity (Qmax=1012.15mgg(-1)) of the composite material have been explained on the basis of synergistic and chelating effects of h-XG/SiO2 with Pb(2+) ion through electrostatic interactions. The kinetics, isotherm and thermodynamics studies reveal that Pb(2+) adsorb rapidly on nanocomposite surface, which is in agreement with pseudo-second-order kinetics and Langmuir adsorption isotherm models. In consequence of excellent adsorption as well as regeneration characteristics of nanocomposite, it has been found to be a promising adsorbent towards removal of Pb(2+) ions from battery industry wastewater. PMID:25164955

  14. The effect of cleaning substances on the surface of denture base material

    PubMed Central

    Žilinskas, Juozas; Junevičius, Jonas; Česaitis, Kęstutis; Junevičiūtė, Gabrielė

    2013-01-01

    Bakcground The aim of this study was to evaluate the effect of substances used for hygienic cleaning of dentures on the surface of the denture base material. Material/Methods Meliodent Heat Cure (Heraeus-Kulzer, Germany) heat-polymerized acrylic resin was used to produce plates with all the characteristics of removable denture bases (subsequently, “plates”). Oral-B Complete toothbrushes of various brush head types were fixed to a device that imitated tooth brushing movements; table salt and baking soda (frequently used by patients to improve tooth brushing results), toothpaste (“Colgate Total”), and water were also applied. Changes in plate surfaces were monitored by measuring surface reflection alterations on spectrometry. Measurements were conducted before the cleaning and at 2 and 6 hours after cleaning. Results No statistically significant differences were found between the 3 test series. All 3 plates used in the study underwent statistically significant (p<0.05changed) – the reflection became poorer. The plates were most affected by the medium-bristle toothbrush with baking soda – the total reflection reduction was 4.82±0.1%; among toothbrushes with toothpaste, the hard-type toothbrush had the greatest reflection-reducing effect – 4.6±0.05%, while the toothbrush with table salt inflicted the least damage (3.5 ± 0.16%) due to the presence of rounded crystals between the bristles and the resin surface. Toothbrushes with water had a uniform negative effect on the plate surface – 3.89±0.07%. Conclusions All substances used by the patients caused surface abrasion of the denture base material, which reduced the reflection; a hard toothbrush with toothpaste had the greatest abrasive effect, while soft toothbrushes inflicted the least damage. PMID:24326781

  15. Reservoir Complete Denture in a Patient with Xerostomia Secondary to Radiotherapy for Oral Carcinoma: A Case Report and Review of Literature

    PubMed Central

    Ladda, R; Kasat, VO; Gangadhar, SA; Baheti, S; Bhandari, AJ

    2014-01-01

    Xerostomia refers to a subjective sensation of dry mouth. A variety of factors can cause xerostomia including radiotherapy (RT) given for the treatment of oral carcinoma. Depending on the cause, treatment is provided to a patient suffering from xerostomia. In severe xerostomia salivary substitutes can be used and if the xerostomic patient is edentulous, then reservoir space for artificial salivary substitute can be created in partial as well as complete upper or lower dentures. The methods advocated so far for incorporating reservoir space in mandibular complete denture are costly, time consuming and require extra-laboratory steps. Therefore, the purpose of this article is to report a simpler method for fabrication of mandibular reservoir denture in a 67-year-old edentulous male patient suffering from xerostomia due to RT for oral carcinoma. PMID:24761252

  16. Does Hollowing of Complete Denture Enhance Retention? – A Pilot Study

    PubMed Central

    Kalra, Ashish; Iyer, Satish R; Mittal, Manish; Kalra, Shilpa; Yadav, Shweta

    2015-01-01

    Introduction Prosthetic rehabilitation is an extremely challenging task in extreme resorption cases of the maxillary denture-bearing area. Reducing the weight of a maxillary obturator has been seen as beneficial. But whether reducing the weight of conventional complete denture also increases retention or not, is still very dubious. The aim of this pilot study was to determine the effect of maxillary denture weight on denture retention and stability. Materials and Methods For this study, a total of 10 patients were considered for the pilot study (06 female and 04 male) with an average age of 70 y. Each patient was provided with two sets of maxillary complete dentures, one hollow labeled as A and one conventional maxillary denture labeled as B. Results It was shown that mean values for retention using MKIS for retention for hollow dentures (A) was 7.8 and for conventional dentures (B) it was 8.2 and the stability for maxillary dentures was more with conventional dentures (B) than hollow maxillary dentures (A) and it was significant as p-value was 0.015 (p<.1). Conclusion The denture retention and stability, chewing and comfort values of conventional dentures and hollow dentures were slightly better for conventional dentures. PMID:26155561

  17. Development of a simultaneous partial nitrification, anaerobic ammonia oxidation and denitrification (SNAD) bench scale process for removal of ammonia from effluent of a fertilizer industry.

    PubMed

    Keluskar, Radhika; Nerurkar, Anuradha; Desai, Anjana

    2013-02-01

    A simultaneous partial nitrification, anammox and denitrification (SNAD) process was developed for the treatment of ammonia laden effluent of a fertilizer industry. Autotrophic aerobic and anaerobic ammonia oxidizing biomass was enriched and their ammonia removal ability was confirmed in synthetic effluent system. Seed consortium developed from these was applied in the treatment of effluent in an oxygen limited bench scale SNAD type (1L) reactor run at ambient temperature (∼30°C). Around 98.9% ammonia removal was achieved with ammonia loading rate 0.35kgNH(4)(+)-N/m(3)day in the presence of 46.6mg/L COD at 2.31days hydraulic retention time. Qualitative and quantitative analysis of the biomass from upper and lower zone of the reactor revealed presence of autotrophic ammonia oxidizing bacteria (AOB), Planctomycetes and denitrifiers as the dominant bacteria carrying out anoxic oxidation of ammonia in the reactor. Physiological and molecular studies strongly indicate presence of anammox bacteria in the anoxic zone of the SNAD reactor. PMID:23313684

  18. Polyamide as a Denture Base Material: A Literature Review

    PubMed Central

    Vojdani, Mahroo; Giti, Rashin

    2015-01-01

    The purpose of this article was to review the biocompatibility, physical, and mechanical properties of the polyamide denture base materials. An electronic search of scientific papers from 1990-2014 was carried out using PubMed, Scopus and Wiley Inter Science engines using the search terms “nylon denture base” and “polyamide denture base”. Searching the key words yielded a total of 82 articles. By application of inclusion criteria, the obtained results were further reduced to 24 citations recruited in this review. Several studies have evaluated various properties of polyamide (nylon) denture base materials. According to the results of the studies, currently, thermo-injectable, high impact, flexible or semi-flexible polyamide is thought to be an alternative to the conventional acrylic resins due to its esthetic and functional characteristics and physicochemical qualities. It would be justifiable to use this material for denture fabrication in some cases such as severe soft/ hard tissue undercuts, unexplained repeated fracture of denture, in aesthetic-concerned patients, those who have allergy to other denture base materials, and in patients with microstomia.  Although polyamide has some attractive advantages, they require modifications to produce consistently better properties than the current polymethyl methacrylate (PMMA) materials. Moreover, since there is a very limited knowledge about their clinical performance, strict and careful follow-up evaluation of the patients rehabilitated with polyamide prosthesis is recommended. PMID:26106628

  19. The Biomechanical Effect of Different Denture Base Materials on the Articular Disc in Complete Denture Wearers: A Finite Element Analysis

    PubMed Central

    El-Zawahry, Mohamed M.; El-Ragi, Ahmed A.; El-Anwar, Mohamed I.; Ibraheem, Eman M.

    2015-01-01

    AIM: The objective of the present study was to evaluate the effect of different denture base materials on the stress distribution in TMJ articular disc (AD) in complete denture wearers. MATERIAL AND METHODS: A three dimensional Finite Element (FEA) models of an individual temporomandibular joint (TMJ) was built on the basis CT scan. The FEA model consisted of four parts: the condyle, the articular disc, the denture base, and the articular eminence skull. Acrylic resin and chrome-cobalt denture base materials were studied. Static loading of 300N was vertically applied to the central fossa of the mandibular second premolar. Stress and strain were calculated to characterize the stress/strain patterns in the disc. RESULTS: The maximum tensile stresses were observed in the anterior and posterior bands of (AD) on load application with the two denture base materials. The superior boundaries of the glenoid fossa showed lower stress than those on the inferior boundaries facing the condyle. CONCLUSIONS: Within the limitations of the present study it may be concluded that: The denture base material may have an effect in stress-strain pattern in TMJ articular disc. The stiffer denture base material, the better the distribution of the load to the underling mandibular supporting structures & reducing stresses induced in the articular disc. PMID:27275270

  20. Computer graphics of center of masticatory forces in complete dentures.

    PubMed

    Ogata, K; Kawahara, K; Kishimoto, E; Ogata, S

    1995-01-01

    1. INTRODUCTION. In dental education, it is valuable to show visually the differences between a good-fitting and an ill-fitting complete denture. A vector of masticatory forces across all the teeth of the denture is available to estimate the capability of the denture. The vector is simple while the forces exerted on a denture are very complex. A vector has only two factors, the point of application (center of force) and the magnitude. Because a complete denture acts as a unit, we can obtain the vector from electrical signals detected by transducers installed in the denture base. The aim of this study was to develop software which is able to show visually to dental students, the differences between the vectors of the dentures of three representative complete denture wearers. 2. METHODS. Three subjects, each with either a good, a moderate or an ill-fitting complete denture, were selected. Subject 1 could use the denture very comfortably during experiment. Subject 2 was uncomfortable at the insertion of the new denture, but after adaptations to the denture he could use it very well. Subject 3 had been uncomfortable during the experiment. A bottom complete denture was divided into upper and lower parts. These were connected by the four force-detecting units which were embedded in approximately the first premolar and second molar regions on both sides of the denture. The electric signals from these units during the chewing of peanuts and raisins (sampling time period: 30 msec) were recorded as digital signals and processed using the computer (Macintosh IIcx, Apple Computer) with the A/D converter (Lab-NB), National Instruments). Center and magnitudes of masticatory force were calculated from all sampling points using our newly developed software scripted by ¿C¿ (MPW C, Apple Computer). On the other hand, a tracing of the external shape of the dentition of the denture was made using the project (V-12, NIKON). The tracing of the dentition, with center and magnitude of

  1. [Daily difficulties associated with full conventional dentures].

    PubMed

    Machado, Flávia Christiane de Azevedo; da Costa, Anna Paula Serêjo; Pontes, Anna Lepríncia Bezerra; Lima, Kenio Costa; Ferreira, Maria Ângela Fernandes

    2013-10-01

    The effectiveness of health services can be evaluated from the quality of life (QOL) standpoint. Thus, this study evaluated rehabilitation services using full conventional dentures (FCD) of Specialized Dental Care Centers (SDCC) in Rio Grande do Norte (RN) regarding daily difficulties associated with these dentures made between 2007 and 2009. A cross-sectional study was conducted with 138 users of these FCD, collecting data by clinical examination and a questionnaire based on the Oral Impacts on Daily Performances index. The Fisher and chi-square tests were used to test the association between the variables. The result was that 42% of users reported difficulties in executing oral activities due to FCDs. These difficulties were more frequent and intense in the activities of eating, speaking and smiling. In general, 58.7% of users did not have functional teeth. In relation to the clinical evaluation of FCDs, 57.2% of upper and 9.2% of lower FCDs were satisfactory. There was an association between difficulty and the absence of functional teeth, but not with inadequate FCDs. Thus, the SDCCs were effective in upper FCD rehabilitation, since the difficulties encountered are within the standard limitations of this type of rehabilitation. On the other hand, the cost-benefit of rehabilitation of lower FCDs must be evaluated. PMID:24061036

  2. A direct bonded fixed partial dental prosthesis: a clinical report.

    PubMed

    Tanoue, Naomi; Tanaka, Takuo

    2015-01-01

    A direct bonded fixed partial dental prosthesis, with a composite resin denture tooth as a pontic, a tri-n-butylborane initiated adhesive resin, and screw posts for reinforcement, was still functioning after an observation period of 20 years. The prosthesis was found to be reliable for long-term clinical use when chemically and mechanically reinforced. PMID:25277033

  3. Clinical gap changes after porcelain firing cycles of zirconia fixed dentures

    PubMed Central

    Bugurman, Bugurman Burcu

    2014-01-01

    PURPOSE The aim of this study was to measure the changes on the marginal and internal adaptation of zirconia based anterior fixed partial dentures after the porcelain firing process. MATERIALS AND METHODS A total of 34 anterior fixed partial dentures using LAVA CAD/CAM system (3M ESPE, Germany) were applied. Two silicone replicas were obtained: one is obtained before porcelain firing process (initial) and the other is obtained after porcelain firing process (final), followed by the examination under a binocular stereomicroscope. Kruskal Wallis and Wilcoxon Signed Ranks tests were used for the statistical analysis (P<.05). RESULTS No statistically significant difference was found between initial and final marginal gap values (P>.05). At the internal gap measurements, final marginal area values (59.54 µm) were significantly lower than the initial marginal area values (68.68 µm)(P<.05). The highest and the lowest internal gap values were observed at the incisal/occlusal area and at the marginal area, respectively. In addition, lower internal gap values were obtained for canines than for central incisors, lateral incisors and premolars at the incisal area (P<.05). CONCLUSION The firing cycles did not affect the marginal gap of Lava CAD/CAM system, but it is controversial for the internal gap. PMID:25006381

  4. Partial Removal of Pore and Loosely Bound Water by Low-Energy Drying Decreases Cortical Bone Toughness in Young and Old Donors

    PubMed Central

    Nyman, Jeffry S.; Gorochow, Lacey E.; Horch, R. Adam; Uppuganti, Sasidhar; Zein-Sabatto, Ahbid; Manhard, Mary Katherine; Does, Mark D.

    2012-01-01

    With an ability to quantify matrix-bound and pore water in bone, 1H nuclear magnetic resonance (NMR) relaxometry can potentially be implemented in clinical imaging to assess the fracture resistance of bone in a way that is independent of current X-ray techniques, which assess bone mineral density as a correlate of bone strength. Working towards that goal, we quantified the effect of partial dehydration in air on the mechanical and NMR properties of human cortical bone in order to understand whether NMR is sensitive to water-bone interactions at low energy and whether such interactions contribute to the age-related difference in the toughness of bone. Cadaveric femurs were collected from male and female donors falling into two age groups: 21 to 60 years of age (young) and 74 to 99 years of age (old). After extracting two samples from the medial cortex of the mid-shaft, tensile tests were conducted on Wet specimens and paired, Partially Dry (PtlD) specimens (prepared by low-energy drying in air to remove ~3% of original mass before testing). Prior analysis by micro-computed tomography found that there were no differences in intra-cortical porosity between the Wet and PtlD specimens nor did an age-related difference in porosity exist. PtlD specimens from young and old donors had significantly less toughness than Wet specimens, primarily due to a dehydration-related decrease in post-yield strain. The low-energy drying protocol did not affect the modulus and yield strength of bone. Subsequent dehydration of the PtlD specimens in a vacuum oven at 62 °C and then 103 °C, with quantification of water loss at each temperature, revealed an age-related shift from more loosely bound water to more tightly bound water. NMR detected a change in both bound and pore water pools with low-energy air-drying, and both pools were effectively removed when bone was oven-dried at 62 °C, irrespective of donor age. Although not strictly significant due to variability in the drying and

  5. Partial removal of pore and loosely bound water by low-energy drying decreases cortical bone toughness in young and old donors.

    PubMed

    Nyman, Jeffry S; Gorochow, Lacey E; Adam Horch, R; Uppuganti, Sasidhar; Zein-Sabatto, Ahbid; Manhard, Mary Katherine; Does, Mark D

    2013-06-01

    With an ability to quantify matrix-bound and pore water in bone, (1)H nuclear magnetic resonance (NMR) relaxometry can potentially be implemented in clinical imaging to assess the fracture resistance of bone in a way that is independent of current X-ray techniques, which assess bone mineral density as a correlate of bone strength. Working towards that goal, we quantified the effect of partial dehydration in air on the mechanical and NMR properties of human cortical bone in order to understand whether NMR is sensitive to water-bone interactions at low energy and whether such interactions contribute to the age-related difference in the toughness of bone. Cadaveric femurs were collected from male and female donors falling into two age groups: 21-60 years of age (young) and 74-99 years of age (old). After extracting two samples from the medial cortex of the mid-shaft, tensile tests were conducted on Wet specimens and paired, Partially Dry (PtlD) specimens (prepared by low-energy drying in air to remove ∼3% of original mass before testing). Prior analysis by micro-computed tomography found that there were no differences in intra-cortical porosity between the Wet and PtlD specimens nor did an age-related difference in porosity exist. PtlD specimens from young and old donors had significantly less toughness than Wet specimens, primarily due to a dehydration-related decrease in post-yield strain. The low-energy drying protocol did not affect the modulus and yield strength of bone. Subsequent dehydration of the PtlD specimens in a vacuum oven at 62°C and then 103°C, with quantification of water loss at each temperature, revealed an age-related shift from more loosely bound water to more tightly bound water. NMR detected a change in both bound and pore water pools with low-energy air-drying, and both pools were effectively removed when bone was oven-dried at 62°C, irrespective of donor age. Although not strictly significant due to variability in the drying and testing

  6. 21 CFR 872.3540 - OTC denture cushion or pad.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...-counter. (b) Classification. (1) Class I if the device is made of wax-impregnated cotton cloth that the... denture cushion or pad is made of a material other than wax-impregnated cotton cloth or if the...

  7. 21 CFR 872.3540 - OTC denture cushion or pad.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-counter. (b) Classification. (1) Class I if the device is made of wax-impregnated cotton cloth that the... denture cushion or pad is made of a material other than wax-impregnated cotton cloth or if the...

  8. 21 CFR 872.3540 - OTC denture cushion or pad.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...-counter. (b) Classification. (1) Class I if the device is made of wax-impregnated cotton cloth that the... denture cushion or pad is made of a material other than wax-impregnated cotton cloth or if the...

  9. 21 CFR 872.3540 - OTC denture cushion or pad.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...-counter. (b) Classification. (1) Class I if the device is made of wax-impregnated cotton cloth that the... denture cushion or pad is made of a material other than wax-impregnated cotton cloth or if the...

  10. 21 CFR 872.3540 - OTC denture cushion or pad.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-counter. (b) Classification. (1) Class I if the device is made of wax-impregnated cotton cloth that the... denture cushion or pad is made of a material other than wax-impregnated cotton cloth or if the...

  11. Fabricating an immediate denture for a medically compromised elderly patient.

    PubMed

    Lee, Ju-Hyoung

    2015-04-01

    Fabricating an immediate denture (ID) in the conventional manner may be complicated and difficult. An alternative technique is described for the fabrication of an ID that eliminates the need for an interim prosthesis and reduces treatment time. PMID:25681356

  12. Peer Review and Quality Assessment in Complete Denture Education.

    ERIC Educational Resources Information Center

    Novetsky, Marvin; Razzoog, Michael E.

    1981-01-01

    A program in peer review and quality assessment at the University of Michigan denture department is described. The program exposes students to peer review in order to assess the quality of their treatment. (Author/MLW)

  13. The various methods and benefits of denture labeling

    PubMed Central

    Datta, Pankaj; Sood, Sonia

    2010-01-01

    Labeled dentures can be important in identifying the owners in case of an accident, loss of memory, states of unconsciousness, being inadvertently misplaced on admission to a hospital or, in identifying the bodies of those who have died in a calamity. Positive identification through labeled dentures plays a key role in forensic scenario. Marking dentures has been considered as an important part of forensic dentistry, although no standardized method is followed. A number of labeling systems are available and can be broadly separated into either surface marking methods or inclusion systems. Each of the commonly described techniques is assessed with respect to their strengths and weaknesses. The more contemporary methods, though hi-tech, are expensive and may not be suitable for all dental practitioners to use. This article reviews the strengths and weaknesses of various methods involved in labeling dentures concluding by recommending that this valuable topic be included in the dental curriculum in India. PMID:21731340

  14. Denture identification using unique identification authority of India barcode

    PubMed Central

    Mahoorkar, Sudhindra; Jain, Anoop

    2013-01-01

    Over the years, various denture marking systems have been reported in the literature for personal identification. They have been broadly divided into surface marking and inclusion methods. In this technique, patient's unique identification number and barcode printed in the patient's Aadhaar card issued by Unique Identification Authority of India (UIDAI) are used as denture markers. This article describes a simple, quick, and economical method for identification of individual. PMID:23960418

  15. Complete denture fabrication supported by CAD/CAM.

    PubMed

    Wimmer, Timea; Gallus, Korbinian; Eichberger, Marlis; Stawarczyk, Bogna

    2016-05-01

    The inclusion of computer-aided design/computer-aided manufacturing (CAD/CAM) technology into complete denture fabrication facilitates the procedures. The presented workflow for complete denture fabrication combines conventional and digitally supported treatment steps for improving dental care. With the presented technique, the registration of the occlusal plane, the determination of the ideal lip support, and the verification of the maxillomandibular relationship record are considered. PMID:26774323

  16. Wispy Prosthesis: A Novel Method in Denture Weight Reduction

    PubMed Central

    Anne, Gopinadh; Budeti, Sreedevi; Anche, Sampath Kumar; Zakkula, Srujana; Atla, Jyothi; Jyothula, Ravi Rakesh Dev; Peddinti, Vijaya Kumar

    2016-01-01

    Introduction Stability and retention of the denture becomes at stake with the increase in weight of the denture prosthesis. As a consequence, different materials and methods have been introduced to overcome these issues but denture weight reduction still remains to be a cumbersome and strenuous procedure. Aim To introduce a novel technique for the fabrication of denture prosthesis where in the weight of the denture will not affect the retention and stability of the denture. Materials and Methods Four groups with a sample size of 10 each, were included where in one group was control and other three were study groups. The control group samples were made completely solid and the study group samples were packed with materials like bean balls, cellulose balls and polyacrylic fibers. The weight of all the samples of each study group was measured and compared with the control group. The observations were analyzed statistically by paired t-test. Results It was observed that the bean balls group produced a weight reduction of 31.3%, cellulose balls group 27.4% and polyacrylic fibers group 24.5% when compared to that of the control group. Conclusion This novel technique will eliminate the problems that were associated in creating hollowness and at the same time will reduce the weight of the prosthesis and among all the study groups, bean balls group were found to reduce maximum weight of the prosthesis. PMID:27190947

  17. Micro secure digital card: A novel method for denture identification

    PubMed Central

    Colvenkar, Shreya S.; Gopal, Sujatha

    2014-01-01

    Aim: Denture labeling is of vital significance in social and forensic scenario. Numerous published work have attempted to present best method for denture marking, however not all satisfy crucial requirement either in terms of cost or storage of large amount of information. Hence, this paper describes a simple, cheap, and feasible denture marking system using portable Micro Secure Digital (MicroSD) card. These cards are created to store, modify, and view large amount of information with mobile phones, which forms an important part in majority of household in India. Materials and Methods: After try-in make a depression slightly wider than the size of the MicroSD card on the external lingual flange of the trial mandibular denture. Process the denture together with acrylic wax flap according to manufacturer's instructions. The acrylic flap is planned in such a way that it is well-flushed with surrounding areas and can be lifted on one side to access the card. MicroSD card is placed in the denture and flap is closed. Conclusion: The proposed method is simple, cheap, and can store large amount of information. PMID:25177141

  18. Do flexible acrylic resin lingual flanges improve retention of mandibular complete dentures?

    PubMed Central

    Ahmed Elmorsy, Ayman Elmorsy; Ahmed Ibraheem, Eman Mostafa; Ela, Alaa Aboul; Fahmy, Ahmed; Nassani, Mohammad Zakaria

    2015-01-01

    Objectives: The aim of this study was to compare the retention of conventional mandibular complete dentures with that of mandibular complete dentures having lingual flanges constructed with flexible acrylic resin “Versacryl.” Materials and Methods: The study sample comprised 10 completely edentulous patients. Each patient received one maxillary complete denture and two mandibular complete dentures. One mandibular denture was made of conventional heat-cured acrylic resin and the other had its lingual flanges made of flexible acrylic resin Versacryl. Digital force-meter was used to measure retention of mandibular dentures at delivery and at 2 weeks and 45 days following denture insertion. Results: The statistical analysis showed that at baseline and follow-up appointments, retention of mandibular complete dentures with flexible lingual flanges was significantly greater than retention of conventional mandibular dentures (P < 0.05). In both types of mandibular dentures, retention of dentures increased significantly over the follow-up period (P < 0.05). Conclusions: The use of flexible acrylic resin lingual flanges in the construction of mandibular complete dentures improved denture retention. PMID:26539387

  19. Partially sulfated lime-fly ash sorbents activated by water or steam for SO{sub 2} removal at a medium temperature

    SciTech Connect

    Liming Shi; Xuchang Xu

    2005-12-01

    Laboratory experiments were conducted to investigate the reactivity of partially sulfated lime-fly ash sorbents activated by water or steam for SO{sub 2} removal. Sulfation tests were performed at 550{sup o}C using a fixed bed reactor under conditions simulating economizer zone injection flue gas desulfurization. Activation experiments were conducted with water or steam using a range of temperatures between 100 and 550{sup o}C. The results showed that the reactivity of the sorbents was closely related to the content of Ca(OH){sub 2} formed in the activation process, which varied with the water or steam temperature. The sulfur dioxide capture capacity of Ca(OH){sub 2} in the sorbent is higher than that of CaO at a medium temperature. Water or steam temperatures in the range of 100-200{sup o}C are favorable to the formation of Ca(OH){sub 2} from CaO. 15 refs., 8 figs., 2 tabs.

  20. Evaluation of the rigidity of dentures made of injection-molded materials.

    PubMed

    Wadachi, Juro; Sato, Masayuki; Igarashi, Yoshimasa

    2013-01-01

    Dentures made of 2 different types of injection-molded thermoplastic resins (polyamide resin and polyester resin) and a denture made of conventional heat-polymerized resin were used to create an experimental model of a mandibular molar region with a two-tooth gap. In the experimental model, a force of 100 N was applied onto the mesial fossa of the first molars of the dentures, and comparisons were performed by measuring the pressure applied under the denture base and the subsidence rate of the denture. The polyamide resin denture showed the highest subsidence, exerted the highest pressure on the underlying mucosa, and showed significant differences with the other types of dentures. The findings showed that polyamide resins have the lowest degree of elasticity, and that when resins with such low elasticities are used in the denture base, they should preferably be reinforced with metals. PMID:23719015

  1. Reestablishment of Occlusal Vertical Dimension in Complete Denture Wearing in Two Stages

    PubMed Central

    Marin, Danny Omar Mendoza; Leite, Andressa Rosa Perin; de Oliveira Junior, Norberto Martins; Compagnoni, Marco Antonio; Pero, Ana Carolina; Arioli Filho, João Neudenir

    2015-01-01

    The assessment and reestablishment of the occlusal vertical dimension (OVD) are considered important factors in the treatment of complete denture wearers. The long-time use of a complete denture can result in jaw displacement due to abrasion of the artificial teeth and residual ridge resorption, causing esthetic complications. Most patients with old dentures and incorrect OVD accept reestablishment of the OVD with new complete dentures, even if they were used to their old dentures. The present clinical report describes a method of gradual reestablishment of OVD using a diagnostic acrylic splint on artificial teeth in old complete dentures before the manufacture of new complete dentures. Clinical Significance. The use of a reversible treatment for reestablishment of the OVD in old complete dentures with a diagnostic occlusal acrylic splint allows for the reestablishment of the intermaxillary relationship, providing physiological conditions of masticatory performance associated with the recovery of facial esthetics in edentulous patients. PMID:26587296

  2. The influence of psychologic factors on patient satisfaction with complete dentures.

    PubMed

    van Waas, M A

    1990-05-01

    This study investigated the relationship between satisfaction with complete dentures and some psychologic factors. New dentures were made for 130 patients who were investigated during their treatment. A neuroticism scale and the Health Locus of Control scale were used to investigate the patient's personality. The patient-dentist relationship was evaluated by asking patients their opinions about the treatment, and patient attitude toward dentures in general and their expectation toward the new dentures were evaluated by means of a questionnaire. No relationship was found between dissatisfaction and patient personality. A low relationship was found between dissatisfaction and the patient's opinion about the treatment, and a moderate relationship was found between dissatisfaction and the patient's attitude toward dentures. A patient's attitude toward dentures, measured by the questionnaire before new dentures were received, is a prospective tool for patient satisfaction with new dentures. PMID:2187082

  3. Electromyographic Evaluation of the Effect of Lined Dentures on Masticatory Muscle Activity in Edentulous Subjects

    PubMed Central

    Srivastava, Shitij; Gaur, Abhishek; Dupare, Arun; Rastogi, Shiksha; Kamatagi, Laxmikant

    2015-01-01

    Aim The purpose of this study was to examine changes in relative electromyographic (EMG) activities of temporal and masseter muscles after relining the dentures with silicone and acrylic-resin based denture liners. Materials and Methods Conventional complete dentures were fabricated for 20 edentulous patients. One month after completing adjustments of the dentures, electromyography of the masseter and temporalis muscle during maximum intercuspation was recorded. The dentures were then relined with a silicone denture liner and after an adaptation period of one month, were again subjected for electromyographic evaluation. Further, the dentures were relined with acrylic denture liner and subjected to electromyographic evaluation. Data was analysed using Statistical Package for Social Sciences (SPSS) version 15.0. Intergroup comparisons were done using ANOVA followed by post-hoc assessments using Tukey HSD test. Results Mean amplitude and duration with conventional dentures was found to be significantly lower as compared to silicone lined and acrylic lined dentures for all the comparisons. Statistically, no significant difference between silicone lined and acrylic lined dentures was observed for any of the comparisons. Conclusion Within the limitations of this experimental design, it was concluded that relining significantly increases electromyographic activity of the masseter and temporalis muscles. Thus, resulting in an improved biting force, chewing efficiency and masticatory performance. There were no significant differences between silicone and acrylic based denture liners for both electromyographic variables. PMID:26436054

  4. 21 CFR 872.3410 - Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... carboxymethylcellulose sodium denture adhesive. 872.3410 Section 872.3410 Food and Drugs FOOD AND DRUG ADMINISTRATION....3410 Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive. (a) Identification. An ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive is a...

  5. 21 CFR 872.3410 - Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... carboxymethylcellulose sodium denture adhesive. 872.3410 Section 872.3410 Food and Drugs FOOD AND DRUG ADMINISTRATION....3410 Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive. (a) Identification. An ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive is a...

  6. 21 CFR 872.3410 - Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... carboxymethylcellulose sodium denture adhesive. 872.3410 Section 872.3410 Food and Drugs FOOD AND DRUG ADMINISTRATION....3410 Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive. (a) Identification. An ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive is a...

  7. 21 CFR 872.3410 - Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... carboxymethylcellulose sodium denture adhesive. 872.3410 Section 872.3410 Food and Drugs FOOD AND DRUG ADMINISTRATION....3410 Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive. (a) Identification. An ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive is a...

  8. 21 CFR 872.3410 - Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... carboxymethylcellulose sodium denture adhesive. 872.3410 Section 872.3410 Food and Drugs FOOD AND DRUG ADMINISTRATION....3410 Ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive. (a) Identification. An ethylene oxide homopolymer and/or carboxymethylcellulose sodium denture adhesive is a...

  9. Spectrogram Analysis of Complete Dentures with Different Thickness and Palatal Rugae Materials on Speech Production

    PubMed Central

    Zaki Mahross, Hamada; Baroudi, Kusai

    2015-01-01

    Objective. To investigate the influence of reproduction of different thickness and palatal rugae materials on complete dentures speech using Computerized Speech Lab (CSL) (spectrogram). Materials and Methods. Three completely edentulous male patients (aged 50–60 years) were selected for reading a paragraph. Twelve upper dentures were constructed, four for each patient. The patients' speech groups were divided into five groups, Group I: patients without dentures; Group II: patients rehabilitated with conventional acrylic dentures; Group III: patients with conventional acrylic dentures with rugae reproduction; Group IV: patients with dentures with metallic framework of minimal thickness and direct ragged metallic palatal surface at rugae area; Group V: patients with dentures with palatal rugae constructed from resilient acrylic resin material with thickness less than conventional denture. Speech samples were recorded after insertion of each denture for groups using Computerized Speech Lab (CSL) (spectrogram). The sounds selected were lingopalatal /s/z/sh/t/d/ and /l/. Results. Group III produced high mean significant difference with /sh/t/ sound. For Group IV, the difference was noticed with /s/z/sh/t/ and /d/ sounds, while for Group V the difference was shown with /z/l/ sound (P < 0.05). Conclusion. It is recommended to reproduce the rugae area in complete denture because the phonetic quality of complete denture with rugae is superior to the conventional denture. PMID:25883655

  10. Fit accuracy of metal partial removable dental prosthesis frameworks fabricated by traditional or light curing modeling material technique: An in vitro study

    PubMed Central

    Anan, Mohammad Tarek M.; Al-Saadi, Mohannad H.

    2015-01-01

    Objective The aim of this study was to compare the fit accuracies of metal partial removable dental prosthesis (PRDP) frameworks fabricated by the traditional technique (TT) or the light-curing modeling material technique (LCMT). Materials and methods A metal model of a Kennedy class III modification 1 mandibular dental arch with two edentulous spaces of different spans, short and long, was used for the study. Thirty identical working casts were used to produce 15 PRDP frameworks each by TT and by LCMT. Every framework was transferred to a metal master cast to measure the gap between the metal base of the framework and the crest of the alveolar ridge of the cast. Gaps were measured at three points on each side by a USB digital intraoral camera at ×16.5 magnification. Images were transferred to a graphics editing program. A single examiner performed all measurements. The two-tailed t-test was performed at the 5% significance level. Results The mean gap value was significantly smaller in the LCMT group compared to the TT group. The mean value of the short edentulous span was significantly smaller than that of the long edentulous span in the LCMT group, whereas the opposite result was obtained in the TT group. Conclusion Within the limitations of this study, it can be concluded that the fit of the LCMT-fabricated frameworks was better than the fit of the TT-fabricated frameworks. The framework fit can differ according to the span of the edentate ridge and the fabrication technique for the metal framework. PMID:26236129

  11. Commercial and Plant Extract Denture Cleansers in Prevention of Candida albicans Growth on Soft Denture Reliner: In Vitro Study

    PubMed Central

    Dhaded, Sunil; Joshi, Shalini

    2016-01-01

    Objective To evaluate and compare the efficacy of two plant extracts and two commercially available denture cleansers against candida albicans adherent to soft denture reline material. Materials and Methods In this study 60 specimens of soft denture reliner material specimens were fabricated with dimensions 10x10x2 mm. The sterile specimens were inoculated by immersion in Sabourand broth containing Candida albicans for 16 hours at 37°C in an incubator. Then the specimens were washed and immersed in denture cleansers which were divided into group five groups from Group I-V for CD Clean®, Nigella sativa, thyme essential oil, Fittydent® and distilled water respectively, for 8 hours at room temperature. Then they were washed, fixed with methanol and stained with crystal violet. Candida cells adherent to the specimens were counted under microscope. The number of cells adherent to test samples were compared with that adherent to control. Results The effectiveness of Fittydent® was more than CD Clean® in reducing the adherent candida albicans and the difference was statically significant (p = <0.001). Both thyme essential oil and nigella sativa were almost same in effectiveness against candida albicans but the difference was not statically significant (p= 0.79). Post-hoc Tukey’s test was performed which indicated that Fittydent® was the most effective amongst the denture cleansers tested in this study, followed by thyme essential oil, nigella sativa and CD Clean®. Conclusion The results of the study showed that all denture cleansers used in the study were significantly effective. The study indicated that Fittydent is more effective amongst the denture cleansers because of its mechanism of action; however the plant extracts used in this study were also significantly effective against candida albicans. PMID:27042584

  12. [Complete dentures in the Dutch population 1981-1992].

    PubMed

    van den Berg, J; Frenken, F J

    1993-09-01

    In the period 1981-1992 the percentage of people with a full set of dentures dropped from 31.6 to 22.5 in the Netherlands (persons > or = 16 years). This is particularly due to the relatively strong decrease in the number of young people with full dentures. Regional differences are remarkable: in the northern provinces the percentage is relatively high; in the province of Utrecht it is relatively low. Recently regional differences appear to be (very) small among the young age groups. Many people with a full set of dentures use the same dentures for a long period: about 20% of them have had their current prostheses for 16-25 years, another 20% for over 25 years. Taking into account the total adult population, it appears that the socio-economic status (SES) negatively correlates with the probability of having a full set of dentures. This holds for all three SES indicators in the study: education, income and type of insurance. But among the young age groups this correlation is only valid for education. PMID:11917875

  13. [Effectivity and durability of telescopic dentures on abutment teeth].

    PubMed

    van den Wijngaarden, E; van Pelt, A W J; Meisberger, E W; Tams, J; Cune, M S

    2016-03-01

    In a study, the effectivity and durability of telescopic dentures on abutment teeth provided with telescope crowns were investigated. The prognosis for the prosthetic structure and for the abutment teeth were both investigated. The survival rate of 234 telescopic dentures (886 abutment teeth) in 147 patients in a general dental practice were retrospectively evaluated on the basis of a status study. The mean survival rate was calculated. This is the moment when 50% of the telescopic dentures had failed. For telescopic dentures in the maxilla, this was 22.3±2.8 years, which did not represent a statistically significant difference from the mandible (20.9±1.9 years). Of the 886 abutment teeth that were used, 127 (14.3%) were extracted after an average period of 11.7 years. Periodontal complications were the primary reason for extraction. Based on this investigation, one could conclude that telescopic dentures are also a durable and sustainable solution in the long term. Loss of abutment teeth is relatively rare and has limited influence on the survival of the prosthetic structure. PMID:26973985

  14. Metal reinforcement of a complete maxillary denture without a palate: a preliminary report.

    PubMed

    Takahashi, Toshihito; Mizuno, Yoko; Gonda, Tomoya; Maeda, Yoshinobu

    2015-01-01

    This preliminary study examined laboratory-simulated differences between maxillary complete dentures with and without a palate (palateless) as well as the effect of reinforcement of the latter design. Five types of experimental dentures and three types of reinforcements were made. Strain gauges were attached, and a vertical load was applied. The strain was statistically compared using analysis of variance (P = .05). Strain recordings on the palatal side of palateless dentures without reinforcement were significantly higher than in complete dentures and palateless dentures with reinforcement (P < .05). These preliminary observations suggest that such reinforcement with a palatal bar or metal-based palate may reduce the risk of fracture and deformation. PMID:25822307

  15. Achieving an esthetic smile with fixed and removal prosthesis using extracoronal castable precision attachments.

    PubMed

    Vaidya, Sharad; Kapoor, Charu; Bakshi, Yujika; Bhalla, Sonam

    2015-01-01

    Satisfactory restoration in a patient with a partially edentulous situation can be challenging especially when unilateral or bilateral posterior segment of teeth is missing. Successful restoration can be done with various conventional and contemporary treatment options. One such treatment modality is attachment-retained cast partial dentures. A key to success for an attachment retained cast partial denture is the strategic selection of teeth for retention. This clinical report discusses rehabilitation of a patient with the help of a combined prosthesis in the upper arch and stud retained overdenture in the lower arch. PMID:26929527

  16. Evaluation of the effect of denture adhesives on surface roughness of two chemically different denture base resins

    PubMed Central

    Darwish, Mahmoud; Nassani, Mohammad Zakaria

    2016-01-01

    Objective: To evaluate the effect of four commercially available denture adhesives (DAs) on surface roughness of two chemically different denture base materials. Materials and Methods: Fifty specimens of heat-cured polymethyl methacrylate, and another fifty specimens of light-cured urethane dimethacrylate were divided into five groups (n = 10), each was immersed in four prepared DAs (Corega Super Cream, Corega Ultra Powder, Olivafix Cream, Protefix Cream) as well as distilled water (control group). The mean surface roughness (Ra) of the polished and unpolished surfaces of the specimens was recorded using profilometer device. T-test for paired observation was used to indicate any changes in surface roughness between the baseline and after 30 days of immersion in the DA. Results: Almost all the tested DAs had no significant effect on the roughness of polished and unpolished surfaces of both denture base materials. The Corega super cream DA produced significant increase in the roughness of the polished surfaces of both types of acrylic specimens (P < 0.05). Conclusion: The majority of the investigated DAs appears not to affect the surface roughness of denture base materials. Only Corega super cream DA produced detectable increase in the roughness of polished surfaces of denture base specimens. PMID:27403047

  17. Hader bar and clip attachment retained mandibular complete denture

    PubMed Central

    Singh, Kunwarjeet; Gupta, Nidhi; Kapoor, Vikram; Gupta, Ridhimaa

    2013-01-01

    Bar and clip attachments significantly improve the level of satisfaction of denture-wearing patients by enhancing the retention and stability of the prosthesis. These attachments have been most commonly used for connecting the prosthesis to implants, but they can be effectively used to retain tooth-supported prosthesis as well. The primary functions of bar attachments are splinting the abutments together, even distribution of forces to the abutments and supporting areas, guiding the prosthesis into place, improving the retention, stability, support and comfort of the patient. The primary requirement for the use of bar attachments is the availability of sufficient vertical and buccolingual space for the proper placement of the bar, sleeves, teeth arrangement and sufficient thickness of acrylic denture base to minimise incidence of denture fracture in the area of bar assembly. PMID:24145505

  18. Complete denture analyzed by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Negrutiu, Meda L.; Sinescu, Cosmin; Todea, Carmen; Podoleanu, Adrian G.

    2008-02-01

    The complete dentures are currently made using different technologies. In order to avoid deficiencies of the prostheses made using the classical technique, several alternative systems and procedures were imagined, directly related to the material used and also to the manufacturing technology. Thus, at the present time, there are several injecting systems and technologies on the market, that use chemoplastic materials, which are heat cured (90-100°C), in dry or wet environment, or cold cured (below 60°C). There are also technologies that plasticize a hard cured material by thermoplastic processing (without any chemical changes) and then inject it into a mold. The purpose of this study was to analyze the existence of possible defects in several dental prostheses using a non invasive method, before their insertion in the mouth. Different dental prostheses, fabricated from various materials were investigated using en-face optical coherence tomography. In order to discover the defects, the scanning was made in three planes, obtaining images at different depths, from 0,01 μm to 2 mm. In several of the investigated prostheses we found defects which may cause their fracture. These defects are totally included in the prostheses material and can not be vizualised with other imagistic methods. In conclusion, en-face OCT is an important investigative tool for the dental practice.

  19. Ceramic dentures manufactured with ultrashort laser pulses

    NASA Astrophysics Data System (ADS)

    Werelius, Kristian; Weigl, Paul

    2004-06-01

    Conventional manufacturing of individual ceramic dental prosthesis implies a handmade metallic framework, which is then veneered with ceramic layers. In order to manufacture all-ceramic dental prosthesis a CAD/CAM system is necessary due to the three dimensional shaping of high strength ceramics. Most CAD/CAM systems presently grind blocks of ceramic after the construction process in order to create the prosthesis. Using high-strength ceramics, such as Hot Isostatic Pressed (HIP)-zirconia, this is limited to copings. Anatomically shaped fixed dentures have a sculptured surface with small details, which can't be created by existing grinding tools. This procedure is also time consuming and subject to significant loss in mechanical strength and thus reduced survival rate once inserted. Ultra-short laser pulses offer a possibility in machining highly complex sculptured surfaces out of high-strength ceramic with negligible damage to the surface and bulk of the ceramic. In order to determine efficiency, quality and damage, several laser ablation parameters such as pulse duration, pulse energy and ablation strategies were studied. The maximum ablation rate was found using 400 fs at high pulse energies. High pulse energies such as 200μJ were used with low damage in mechanical strength compared to grinding. Due to the limitation of available laser systems in pulse repetition rates and power, the use of special ablation strategies provide a possibility to manufacture fully ceramic dental prosthesis efficiently.

  20. THE COMPATIBILITY OF DENTURE CLEANSERS AND RESILIENT LINERS

    PubMed Central

    Oliveira, Luciana Valadares; Mesquita, Marcelo Ferraz; Henriques, Guilherme Elias Pessanha; Consani, Rafael Leonardo Xediek; Fragoso, Wagner Sotero

    2006-01-01

    Purpose: Difficulty in cleaning resilient denture liners remains a material disadvantage. The purpose of the present study was to evaluate the effect of denture cleansers on hardness of resilient liner materials. Materials and Methods: Three resilient liners, Luci Sof® (Dentsply), Molloplast-B® (Dentax), and Sofreliner® (Tokuyama), and two denture cleansers, Efferdent® (Warner-Lamber), and 0.5% alkaline hypochlorite preparation were used. Twenty specimens of each material were prepared, measuring 25X15X3mm. Two denture cleansing approaches were used: 1) alkaline hypochlorite, for 20 minutes; 2) alkaline peroxide, for 30 minutes. This procedure was repeated 8 times a day, during 90 days. The specimens were evaluated before and after 360 and 720 cycles, to simulate 1 and 2 years of clinical cleaning procedures, respectively. The Shore A hardness was evaluated in a durometer (Teclock GS-709A), with a penetrating load of 10N for 1 second. Any macroscopic changes, such as loss of color or alteration in surface texture were recorded by one observer. All numeric data were subject to ANOVA with repeated measures followed by Tukey's test (α= 0.05). Results: All materials were significantly different, independently to time and treatment. Initially, Luci Sof® and Sofreliner® immersed in either hypochlorite or peroxide increased the hardness mean values significantly. These hardness mean values decreased significantly after 720 cycles. Molloplast-B® showed no significant difference after the treatments, in any time. Conclusions: Denture cleansers had no effect on hardness of the resilient denture liners evaluated after 2 years of in vivo simulated conditions of hygiene. Sofreliner® was the smoothest material before and after all treatments. PMID:19089278

  1. A new method of marking dentures using microchips.

    PubMed

    Rajan, M; Julian, R

    2002-06-01

    Over the years various methods of denture marking have been reported in the literature. They include surface marking and inclusion techniques using metallic or non-metallic materials, microchips and microlabels. The microchips are preferred because of their small size and aesthetic acceptability. They are not however widely used due to the high cost of manufacture and data incorporation. This article details the procedures involved in inscribing a microchip using the photochemical etching process used in the electronics industry. The resulting microchip was cosmetically appealing, cost effective and was able to satisfy all the forensic requirements for a suitable denture marker. PMID:12085521

  2. Denture barcoding in forensic dentistry: A future option

    PubMed Central

    Basavanna, Jayaprakash Mugur; Jain, Abhishek; Misra, Sumit Kumar

    2016-01-01

    Neurodegenerative disorders are commonly seen in elderly individuals. Parkinson's disease (PD) is the most common example with memory loss, lack of logic, reasoning and analytical thinking. In this case report simple method of 2D Bar code technique of denture marking has been explained which will not only useful in patients with memory loss but it is very helpful in identifying the individuals in case of natural calamities like floods, earthquake, tornedo, state of unconsciousness and accidents. Such patients can be traced easily by denture barcoding. This technique is a major breakthrough in the field of forensic dentistry. PMID:27051224

  3. Denture barcoding in forensic dentistry: A future option.

    PubMed

    Basavanna, Jayaprakash Mugur; Jain, Abhishek; Misra, Sumit Kumar

    2016-01-01

    Neurodegenerative disorders are commonly seen in elderly individuals. Parkinson's disease (PD) is the most common example with memory loss, lack of logic, reasoning and analytical thinking. In this case report simple method of 2D Bar code technique of denture marking has been explained which will not only useful in patients with memory loss but it is very helpful in identifying the individuals in case of natural calamities like floods, earthquake, tornedo, state of unconsciousness and accidents. Such patients can be traced easily by denture barcoding. This technique is a major breakthrough in the field of forensic dentistry. PMID:27051224

  4. [COMBINED ACRYLIC-POLYPROPYLEN REMOVABLE PROSTHESES FOR PROSTHODONTIC TREATMENT].

    PubMed

    Shuturminsky, V

    2015-10-01

    The article deals with the development of methods to prevent complications with prosthetic dentures patients with psychiatric status. The authors developed a method of manufacturing the denture using modern thermoplastic materials, the use of which in practice does not cause prosthetic stomatitis in patients with psychiatric status. The proposed methodology has been tested clinically. Based on Schiller- Pisarev and study fixation of prostheses has been shown the advantage of the prosthesis used for prosthetics partial dentition defects that can not be fixed prosthetics in this category of patients. PMID:26483367

  5. Comparative Evaluation of Sorption, Solubility and Microhardness of Heat Cure Polymethylmethacrylate Denture Base Resin & Flexible Denture Base Resin

    PubMed Central

    Bulbule, Nilesh; Kulkarni, Shilpa; Shah, Riddhi; Kakade, Dilip

    2014-01-01

    Aim: The aim of the study was to evaluate and compare sorption, solubility and microhardness of heat cure polymethylmethacrylate (PMMA) denture base resin and flexible (thermoplastic polyamide nylon) denture base resin. Materials and Methods: Sorption, solubility and microhardness were assessed to determine compliance with ADA Specification no. 12. Results were assessed using statistical and observational analyses. Result: All materials satisfied ADA requirements for sorption, solubility and microhardness. Heat cure PMMA showed more sorption, solubility and microhardness than flexible (thermoplastic polyamide nylon). Conclusion: Flexible (thermoplastic polyamide nylon) resin absorbs less water, is less soluble and is more flexible than PMMA. PMID:25302291

  6. Partial removal of PCDD/Fs, coplanar PCBS, and PCBS from municipal solid waste incineration fly ash by a column flotation process.

    PubMed

    Huang, Ying; Takaoka, Masaki; Takeda, Nobuo; Oshita, Kazuyuki

    2007-01-01

    Municipal solid waste incineration (MSWI) fly ash has recently attracted much attention because of its large quantity and enrichment of high toxic combustion generating organohalogen contaminants such as polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), coplanar polychlorinated biphenyls (coplanar PCBs), and polychlorinated biphenyls (PCBs). Since the organohalogen contaminants in MSWI fly ash are known to be enriched in the unburnt carbon (UC) fraction, the organohalogen contaminants can therefore be removed by the removal of UC. In this research, we used a modified column flotation technique to remove the organic contaminants from MSWI fly ash. UC was removed for 27.7% under the flotation condition without chemical flotation aids. The removal efficiencies of UC, PCDD/Fs, coplanar PCBs, and PCBs are further improved by adding flotation aids during the flotation process. UC was removed for 49.0% by adding a collector assistant with a HLB value of 13.5 and a concentration in the kerosene of 3% during the flotation process. In addition,the UC removal efficiencies are increased with the decrease of the diameter of the micropores in the gas spargers. By optimizing the flotation condition, 41.9% total PCDD/Fs, 40.8% coplanar PCBs, and 44.1% PCBs with 64.0% UC have been successfully removed from MSWI fly ash. The total toxic equivalent (TEQ) of the fly ash was decreased from 6.2 ng/g to 4.2 ng/g in the residue. PMID:17265956

  7. Enhancing Fracture and Wear Resistance of Dentures/Overdentures Utilizing Digital Technology: A Case Series Report.

    PubMed

    Afify, Ahmed; Haney, Stephan

    2016-08-01

    Since it was first introduced into the dental world, computer-aided design/computer-aided manufacturing (CAD/CAM) technology has improved dramatically in regards to both data acquisition and fabrication abilities. CAD/CAM is capable of providing well-fitting intra- and extraoral prostheses when sound guidelines are followed. As CAD/CAM technology encompasses both surgical and prosthetic dental applications as well as fixed and removable aspects, it could improve the average quality of dental prostheses compared with the results obtained by conventional manufacturing methods. The purpose of this article is to provide an introduction into the methods in which this technology may be used to enhance the wear and fracture resistance of dentures and overdentures. This article will also showcase two clinical reports in which CAD/CAM technology has been implemented. PMID:26916680

  8. [Preparation of carbon fiber reinforced fluid type resin denture (author's transl)].

    PubMed

    Kasuga, H; Sato, H; Nakabayashi, N

    1980-01-01

    Transverse strength of cured fluid resins is weaker than that of the heat cured. We have studied to improve the mechanical strength of self-cured acrylic resin by application of carbon fibers as reinforcement and simple methods which must be acceptable for technicians are proposed. A cloth type carbon fiber was the best reinforcement among studied carbon fibers such as chopped or mat. The chopped fibers were difficult to mix homogeneously with fluid resins and effectiveness of the reinforcement was low. Breaking often occurred at the interface between the reinforcement and resin in the cases of mat which gave defects to the test specimens. To prepare reinforced denture, the cloth was trimmed on the master cast after removal of wax and the prepreg was formed with the alginate impression on the cast by Palapress and the cloth. Other steps were same as the usual fluid resin. PMID:6929856

  9. The cast aluminum denture base. Part II: Technique.

    PubMed

    Halperin, A R; Halperin, G C

    1980-07-01

    A technique to wax-up and cast an aluminum base and a method to incorporate the base into the final denture base has been discussed. This technique does not use induction casting, rather it uses two casting ovens and a centrifugal casting machine. PMID:6991680

  10. Denture-Related Stomatitis Is Associated with Endothelial Dysfunction

    PubMed Central

    Osmenda, Grzegorz; Nowakowski, Daniel; Wilk, Grzegorz; Maciąg, Anna; Mikołajczyk, Tomasz; Sagan, Agnieszka; Filip, Magdalena; Dróżdż, Mirosław; Guzik, Tomasz J.

    2014-01-01

    Oral inflammation, such as periodontitis, can lead to endothelial dysfunction, accelerated atherosclerosis, and vascular dysfunction. The relationship between vascular dysfunction and other common forms of oral infections such as denture-related stomatitis (DRS) is unknown. Similar risk factors predispose to both conditions including smoking, diabetes, age, and obesity. Accordingly, we aimed to investigate endothelial function and major vascular disease risk factors in 44 consecutive patients with dentures with clinical and microbiological features of DRS (n = 20) and without DRS (n = 24). While there was a tendency for higher occurrence of diabetes and smoking, groups did not differ significantly in respect to major vascular disease risk factors. Groups did not differ in main ambulatory blood pressure, total cholesterol, or even CRP. Importantly, flow mediated dilatation (FMD) was significantly lower in DRS than in non-DRS subjects, while nitroglycerin induced vasorelaxation (NMD) or intima-media thickness (IMT) was similar. Interestingly, while triglyceride levels were normal in both groups, they were higher in DRS subjects, although they did not correlate with either FMD or NMD. Conclusions. Denture related stomatitis is associated with endothelial dysfunction in elderly patients with dentures. This is in part related to the fact that diabetes and smoking increase risk of both DRS and cardiovascular disease. PMID:25045683

  11. The effect of a commercial probiotic drink on oral microbiota in healthy complete denture wearers

    PubMed Central

    Sutula, Justyna; Coulthwaite, Lisa; Thomas, Linda; Verran, Joanna

    2012-01-01

    Background It is acknowledged that oral and general health status declines with age. The global population of denture wearers is increasing, so is the incidence of denture biofilm-related problems, such as denture-associated stomatitis, aspiration pneumonia and malodour. It has been suggested that consumption of probiotic bacteria may improve oral health. However, the effects of probiotics on the oral microbiota of denture wearers have received little attention. Methods The aim of this study was to investigate the effect of consumption of a commercial probiotic product (Yakult) on microbiota of saliva, tongue and denture biofilm in healthy complete denture wearers. Eight healthy complete denture-wearing National Health Service (NHS) patients undertook a 7-week trial comprising three phases: baseline; 4-week consumption of one bottle of Yakult per day, each containing a minimum 6.5×109 viable cells of Lactobacillus casei strain Shirota (LcS); 4-week washout period. The microbial viability and composition of saliva, tongue dorsum coating and denture biofilm were assessed using a range of solid selective and indicator media. Questionnaires were used to explore participants’ denture cleaning habits and impact of wearing dentures on their life quality and well-being [modified oral health impact profile (OHIP-14)] prior to and after the study. Results Seven volunteers (1 male, 6 females) completed the trial. LcS temporarily colonised oral cavity and denture surface. There was no significant change in the viability of Streptococcus mutans, acidogenic microorganisms, total anaerobic species and Gram-negative obligate anaerobes between study phases. There was no obvious effect of LcS on occurrence and viability of Candida. Participants presented a good general knowledge of denture hygiene and their responses to OHIP-14 questionnaires improved after completing the study (p=0.16). Conclusion It appeared that 4-week consumption of probiotic drink had no overall effect on

  12. Clinical study on thermography, as modern investigation method for Candida-associated denture stomatitis.

    PubMed

    Iosif, Laura; Preoteasa, Cristina Teodora; Murariu-Măgureanu, Cătălina; Preoteasa, Elena

    2016-01-01

    Candida-associated denture stomatitis is an infectious inflammatory condition of the oral mucosa, with frequent recurrences. The aim of this study was to assess the use of infrared thermography as investigation method for Candida-associated denture stomatitis (as inflammatory disorder of the maxillary denture bearing area), by comparing disease and non-disease groups. An observational study was conducted on maxillary edentulous patients treated by acrylic dentures, with and without Candida-associated denture stomatitis. Diagnostic test methods used were clinical examination for denture stomatitis and conventional microbiological culture method for oral candidiasis. Thermography analysis of the maxillary denture bearing area was made using the ThermaCAM PM350 infrared camera (Inframetrics, Flir Systems) and ThermaGram Pro 95 software, data being acquired by usage of standard protocol of thermographic registrations. The sample included 52 patients, 21 with and 31 without Candida-associated denture stomatitis. The temperature of the maxillary mucosa corresponding to the denture bearing area was found to be statistically significantly higher in Candida-associated denture stomatitis (mean 36.20°C), compared to healthy oral mucosa (mean 34.85°C). The thermal threshold value of 35.44°C was identified as best differentiating a pathological from normal state of the maxillary mucosa corresponding to the denture bearing area. In conclusion, infrared thermography, a rapid non-invasive investigation method, has the premises to bring valuable data in inflammatory disorders of the maxillary denture bearing area, as Candida-associated denture stomatitis that may be used for screening, diagnostic or monitoring purposes. PMID:27151707

  13. Posterior implants for distal extension removable prostheses: a retrospective study.

    PubMed

    Mitrani, Ricardo; Brudvik, James S; Phillips, Keith M

    2003-08-01

    Common complaints associated with the Kennedy Class I (bilateral free end) and Class II (unilateral free end) removable partial denture situations are lack of stability, minimal retention, and unesthetic retentive clasping. Some of the same complaints have been reported for implant overdentures with only anterior implants. Starting in 1995, 10 of these patients were treated at the University of Washington with posterior osseointegrated implants to provide stability and/or retention of the removable prostheses, eliminating the need for clasps when possible. This article describes implant alternatives and prosthesis designs and presents a follow-up clinical evaluation of at least 1 year consisting of patient satisfaction, radiographic examination, and soft tissue health. Two groups were evaluated. Group 1 included patients whose implants were used as vertical stops for mandibular distal extension prostheses. Care was taken to ensure that the implants were not loaded laterally by creating a single-point contact at the center of a modified healing abutment. In these cases, sufficient retention was available from the anterior teeth and/or implant abutments. Group 2 included patients whose implants required retention because of lack of adequate tooth abutments. In those cases, a resilient type of attachment was used, which allowed for a small divergence from the path of insertion. Results indicated consistent increased satisfaction in all patients, minimal component wear, no radiographic evidence of excessive bone loss, and stable peri-implant soft tissues. PMID:12956479

  14. Effect of denture cleansers on surface hardness of resilient denture liners at various time intervals- an in vitro study

    PubMed Central

    Pahuja, Rasleen Kaur; Bansal, Sanjay

    2013-01-01

    PURPOSE This study was aimed to determine the effect of two chemically distinct denture cleansers and water on the surface hardness of acrylic and silicone based soft denture liners at various time intervals. MATERIALS AND METHODS Two commonly used commercial resilient liner material were selected based on their chemical composition (silicone- and acrylic-based soft liners) for this investigation. 120 cylindrical specimens were made of 15 mm × 10 mm dimensions (according to ASTM: D-2240-64T) in a custom made metal mold. All specimens were stored in artificial saliva throughout the study. Forty specimens were cleansed daily in 0.5% sodium hypochlorite solution; forty were cleansed in sodium perborate and remaining forty specimens were daily rinsed in water. Testing was done at 1 week, 1 month, 3 months and 6 months for surface hardness using a Shore A Durometer. A mean of 3 reading for each sample was subjected to one-way ANOVA, Post Hoc test and pair-t test for statistical analysis. P values of less than 0.05 were taken as statistically significant. RESULTS Surface hardness of all the samples was significantly higher after a period of 6 months irrespective of the cleansing treatment. Minor changes were observed between control, sodium hypochlorite and sodium perborate groups with time. Greater change was observed in surface hardness of acrylic-based soft denture liners as compared to silicone-based soft liners for all groups, as time progressed. CONCLUSION Silicone-based soft denture liners performed significantly better in all cleansing treatments than acrylic-based soft denture liners. PMID:24049568

  15. A multi-station machine for the fatigue testing of denture base materials.

    PubMed

    Manley, T R; Stonebanks, J A

    1980-07-01

    A multi-station machine has been designed and built to determine the resistance to fatigue failure of denture base materials. The machine has enabled complete S-N curves to be plotted for conventional and reinforced denture base materials involving many megacycles of operation. The resistance to fatigue failure of conventional denture base polymers is similar to that of 'Perspex'; that of PMMA reinforced with carbon fibre is of an order of magnitude greater. PMID:7470562

  16. A survey assessing modes of maintaining denture hygiene among elderly patients

    PubMed Central

    Saha, Ashishtaru; Dutta, Sudipto; Varghese, Rana K.; Kharsan, Vinay; Agrawal, Anil

    2014-01-01

    Objective: To determine the denture hygiene habits in complete denture wearers. Materials and Methods: In this study, a self-administered structured questionnaire was developed to know the attitude of the patients from the Department of Prosthodontics regarding denture hygiene. The study sample consisted of totally 500 subjects, which included 284 (56.8%) males and 216 (43.2%) females. Data were analyzed using SPSS version 15.0 with Chi-square (χ2) test at P < 0.05. Results: Nearly half of the subjects cleaned their dentures daily once. Participants from the younger age group and who had been wearing dentures since 2 years maintained better frequency of cleaning. The majority of these subjects used water and brush for denture cleansing. After seeing the condition, more than half of the dentures were rated as poor (60%). There was significant difference between all the groups on comparison (P = 0.001). Conclusion: Poor condition of complete dentures seen in the population is mainly due to irregular cleansing habits and also less usage of cleansing solutions. Dentists should give proper instructions regarding maintenance of denture hygiene. PMID:25374830

  17. Alternative procedure to improve the stability of mandibular complete dentures: a modified neutral zone technique.

    PubMed

    Rehmann, Peter; Zenginel, Martha; Wostmann, Bernd

    2012-01-01

    The aim of this report is to describe an alternative technique to record the neutral zone. An acrylic resin base with posterior occlusal rims was applied using a thermoplastic denture adhesive. After being worn for 2 days, the base was transferred into an acrylic resin complete denture. Most patients reported an improvement in denture stability and a reduction of pressure sores. This procedure seems to be helpful to improve denture function, especially in the mandible, in patients who cannot be treated with implants. However, because of its complexity, this neutral zone technique cannot be recommended for routine clinical use. PMID:22930774

  18. Hybrid approach to fabrication of hollow internally weighted mandibular denture: A case report

    PubMed Central

    Hazari, Puja; Mishra, Sunil Kumar

    2015-01-01

    Preservation of ridge dimensions is critical for denture success. For long the concept of an internally weighted denture, which suggested that gravity and the additional weight to the mandibular complete denture aids in prosthetic retention is widely accepted. However, excessive weight and pressure can accelerate bone resorption. Here, we describe a unique modification of internally weighted metal denture base for the resorbed mandibular ridge with an incorporated additional hollow section over the anterior knife-edge ridge. The weight provided retention and stability while the hollow portion prevented further resorption of the bone. PMID:26604604

  19. Validation of the Geriatric Oral Health Assessment Index in complete denture wearers.

    PubMed

    Campos, J A D B; Zucoloto, M L; Geremias, R F; Nogueira, S S; Maroco, J

    2015-07-01

    To perform a validation of the Geriatric Oral Health Assessment Index (GOHAI) for complete denture wearers and present a proposal for estimation of perceived oral health. This is a cross-sectional study with non-probabilistic sampling. A total of 211 subjects with a mean age of 62·5 (s.d. = 11·4) years participated, being 169 female. The GOHAI was applied in a personal interview. The construct/convergent/discriminant validity was tested using structural equation modelling. Confirmatory factor analysis was used to verify the fit of three proposals of the GOHAI: three-factor, one-factor and second-order hierarchical models. The stability of the models was evaluated in independent samples. The three-factor model presented an inadequate fit, and items 3, 4 and 9 were removed. The new structure presented an acceptable fit and strong invariance in independent samples. The convergent, discriminant validity and internal consistency were below adequate. The one-factor model presented an adequate fit to the sample. Convergent validity was compromised. A strong invariance of the one-factor model was observed. To calculate the overall scores of the GOHAI factors (three-factor model) or of the oral health perception (one-factor model), a matrix of regression weights for each item in the model was presented as a suggestion. We found an adequate fit of the both structures of the GOHAI for denture wearers, but the three-factor structure was more parsimonious. We suggested considering the weights of the regression model to calculate the overall score of perceived oral health or of its factors in different samples. PMID:25754792

  20. Comparative evaluation of the effect of denture cleansers on the surface topography of denture base materials: An in-vitro study

    PubMed Central

    Jeyapalan, Karthigeyan; Kumar, Jaya Krishna; Azhagarasan, N. S.

    2015-01-01

    Aims: The aim was to evaluate and compare the effects of three chemically different commercially available denture cleansing agents on the surface topography of two different denture base materials. Materials and Methods: Three chemically different denture cleansers (sodium perborate, 1% sodium hypochlorite, 0.2% chlorhexidine gluconate) were used on two denture base materials (acrylic resin and chrome cobalt alloy) and the changes were evaluated at 3 times intervals (56 h, 120 h, 240 h). Changes from baseline for surface roughness were recorded using a surface profilometer and standard error of the mean (SEM) both quantitatively and qualitatively, respectively. Qualitative surface analyses for all groups were done by SEM. Statistical Analysis Used: The values obtained were analyzed statistically using one-way ANOVA and paired t-test. Results: All three denture cleanser solutions showed no statistically significant surface changes on the acrylic resin portions at 56 h, 120 h, and 240 h of immersion. However, on the alloy portion changes were significant at the end of 120 h and 240 h. Conclusion: Of the three denture cleansers used in the study, none produced significant changes on the two denture base materials for the short duration of immersion, whereas changes were seen as the immersion periods were increased. PMID:26538915

  1. Tensile bond strength of silicone-based soft denture liner to two chemically different denture base resins after various surface treatments.

    PubMed

    Akin, Hakan; Tugut, Faik; Guney, Umit; Kirmali, Omer; Akar, Turker

    2013-01-01

    This study evaluated the effect of various surface treatments on the tensile bond strength of a silicone-based soft denture liner to two chemically different denture base resins, heat-cured polymethyl methacrylate (PMMA), and light-activated urethane dimethacrylate or Eclipse denture base resin. PMMA test specimens were fabricated and relined with a silicone-based soft denture liner (group AC). Eclipse test specimens were prepared according to the manufacturer's recommendation. Before they were relined with a silicone-based soft denture liner, each received one of three surface treatments: untreated (control, group EC), Eclipse bonding agent applied (group EB), and laser-irradiated (group EL). Tensile bond strength tests (crosshead speed = 5 mm/min) were performed for all specimens, and the results were analyzed using the analysis of variance followed by Tukey's test (p = 0.05). Eclipse denture base and PMMA resins presented similar bond strengths to the silicone-based soft denture liner. The highest mean force was observed in group EL specimens, and the tensile bond strengths in group EL were significantly different (p < 0.05) from those in the other groups. PMID:22447403

  2. Severe acute respiratory failure managed with continuous positive airway pressure and partial extracorporeal carbon dioxide removal by an artificial membrane lung. A controlled, randomized animal study.

    PubMed

    Borelli, M; Kolobow, T; Spatola, R; Prato, P; Tsuno, K

    1988-12-01

    Using an animal model of acute respiratory failure (ARF), we evaluated two treatments: conventional mechanical pulmonary ventilation (MV) and continuous positive airway pressure (CPAP) with extracorporeal removal of CO2 by an artificial membrane lung. We developed a model of "mild" ARF and a model of "severe" ARF after ventilating healthy sheep at a peak inspiratory pressure of 50 cm H2O for various lengths of time. Sheep from either injury models were randomly assigned to one of the above treatment groups. All 16 sheep from the model with "severe" ARF died, with progressive deterioration in pulmonary function and multiorgan failure irrespective of the treatment. Of 11 sheep from the model with "mild" ARF treated by MV, only three survived, whereas all 11 sheep from the model with "mild" ARF treated with CPAP and extracorporeal removal of CO2 responded well, and nine sheep ultimately recovered. We conclude that CPAP with extracorporeal removal of CO2 provided a better environment for the recovery in our model with "mild" ARF than the conventional arrangement centered on MV alone. Our studies also suggest that lung injury can progress (i.e., model with "severe" ARF) to where neither of the two treatments can succeed. PMID:3144216

  3. Effect of cooling procedure on final denture base adaptation.

    PubMed

    Ganzarolli, S M; Rached, R N; Garcia, R C M R; Del Bel Cury, A A

    2002-08-01

    Well-fitted dentures prevent hyperplasic lesions, provide chewing efficiency and promote patient's comfort. Several factors may affect final adaptation of dentures, as the type of the acrylic resin, the flask cooling procedure and the water uptake. This investigation evaluated the effect of water storage and two different cooling procedures [bench cooling (BC) for 2 h; running water (RW) at 20 degrees C for 45 min] on the final adaptation of denture bases. A heat-cured acrylic resin (CL, Clássico, Clássico Artigos Odontológicos) and two microwave-cured acrylic resins [Acron MC, (AC) GC Dent. Ind. Corp.; Onda Cryl (OC), Clássico Artigos Odontológicos] were used to make the bases. Adaptation was assessed by measuring the weight of an intervening layer of silicone impression material between the base and the master die. Data was submitted to ANOVA and Tukey's test (0.05). The following means were found: (BC) CL=0.72 +/- 0.03 a; AC=0.70 +/- 0.03 b; OC=0.76 +/- 0.04 c//(RW) CL= 1.00 +/- 0.11 a; AC=1.00 +/- 0.12 a; OC=0.95 +/- 0.10 a. Different labels join groups that are not statistically different (P > 0.05). Comparisons are made among groups submitted to the same cooling procedure (BC or RW). The conclusions are: interaction of type of material and cooling procedure had a statistically significant effect on the final adaptation of the denture bases (P < 0.05); water storage was not detected as a source of variance (P > 0.05) on the final adaptation. PMID:12220348

  4. Case report: immediate dentures in an HIV positive patient.

    PubMed

    Singh, Puneeta H; Jones, John D

    2014-07-01

    A 35-year-old patient with a previous history of recreational drug use, mainly cocaine, presented to the UTHSCSA Dental School with grossly carious remaining dentition. The pattern of the wear and caries on the teeth also indicated other recreational drug such as methamphetamine over a long period of time. He was planned for extractions of the remaining teeth and placement of immediate dentures considering the patient's wish for not being edentulous for the healing period. PMID:25265685

  5. Conventional Complete Denture in Patients with Ectodermal Dysplasia

    PubMed Central

    Vilanova, Larissa Soares Reis; Sánchez-Ayala, Alfonso; Ribeiro, Giselle Rodrigues; Campos, Camila Heitor; Farias-Neto, Arcelino

    2015-01-01

    Ectodermal dysplasia is described as heritable conditions that involve anomalies of structures derived from the ectoderm, including hypodontia. In the cases of edentulous young patients, who did not finish their craniofacial growth, treatment with conventional complete denture is a suitable alternative. The aim of this study was to report a case of mandibular edentulism treated with conventional complete denture in a thirteen-year-old patient diagnosed with hidrotic ectodermal dysplasia. Typical features, such as frontal bossing, depressed nasal bridge, protuberant lips, scarce hair, and brittle nails, were visualized during the extraoral examination. The intraoral inspection and radiographic analysis revealed oligodontia, dental malformation, and prolonged retention of deciduous teeth at maxilla and total edentulism at mandible. A conventional complete denture was planned and constructed following the same steps of technique as recommended in adults. Although this option is not a definitive treatment, the patient and his parents were satisfied with his improvement in chewing and speech, as well as with the aesthetic benefits. PMID:26425372

  6. Cytocompatible antifungal acrylic resin containing silver nanoparticles for dentures

    PubMed Central

    Acosta-Torres, Laura Susana; Mendieta, Irasema; Nuñez-Anita, Rosa Elvira; Cajero-Juárez, Marcos; Castaño, Víctor M

    2012-01-01

    Background Inhibition of Candida albicans on denture resins could play a significant role in preventing the development of denture stomatitis. The safety of a new dental material with antifungal properties was analyzed in this work. Methods Poly(methyl methacrylate) [PMMA] discs and PMMA-silver nanoparticle discs were formulated, with the commercial acrylic resin, Nature-CrylTM, used as a control. Silver nanoparticles were synthesized and characterized by ultraviolet-visible spectroscopy, dispersive Raman spectroscopy, and transmission electron microscopy. The antifungal effect was assessed using a luminescent microbial cell viability assay. Biocompatibility tests were carried out using NIH-3T3 mouse embryonic fibroblasts and a Jurkat human lymphocyte cell line. Cells were cultured for 24 or 72 hours in the presence or absence of the polymer formulations and analyzed using three different tests, ie, cellular viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and cell proliferation by enzyme-linked immunosorbent assay BrdU, and genomic DNA damage (Comet assay). Finally, the samples were evaluated mechanically, and the polymer-bearing silver nanoparticles were analyzed microscopically to evaluate dispersion of the nanoparticles. Results The results show that PMMA-silver nanoparticle discs significantly reduce adherence of C. albicans and do not affect metabolism or proliferation. They also appear not to cause genotoxic damage to cells. Conclusion The present work has developed a new biocompatible antifungal PMMA denture base material. PMID:22969297

  7. Effects of Mucosal Thickness on the Stress Distribution and Denture Stability of Mandibular Implant-Supported Overdentures with Unsplinted Attachments In Vitro

    PubMed Central

    Haruta, Asuka; Matsushita, Yasuyuki; Tsukiyama, Yoshihiro; Sawae, Yoshinori; Sakai, Nobuo; Koyano, Kiyoshi

    2011-01-01

    The aim of this study was to compare the effects of mucosal thickness on the stress pattern around implants and movement of implant-supported overdentures with ball/female and three different types of magnetic attachments. After insertion of two root-form implants into a mandibular model, the surface of the model was covered with a 1.5- or 3-mm layer of impression material to simulate the oral mucosa, and removable overdentures were fabricated on each model. A 50-N vertical force was applied to the right first molar, and the resultant stress distribution and denture movement were measured. In the 1.5-mm mucosal model, the magnetic attachments showed significantly lower bending moments than did the ball attachment. The denture base displacement was the lowest on a magnetic attachment. In this study, use of magnetic attachments could be advantageous for mandibular implant-supported overdentures based on lower stress and better denture stability especially in the thin mucosal model. PMID:21799705

  8. Three dimensional deformation of dry-stored complete denture base at room temperature

    PubMed Central

    2016-01-01

    PURPOSE The aim of this study was to evaluate whether there is any typical deformation pattern existing in complete denture when it was dried by using the 3D scanner and surface matching program. MATERIALS AND METHODS A total of 28 denture bases were fabricated with heat curing acrylic resin (each 14 upper and lower denture bases), and 14 denture bases (each 7 upper and lower denture bases) were stored in the water bottle (water stored), and another 14 denture bases were stored in the air (dry stored). Each specimen was scanned at 1st day after deflasking, 14th day after deflasking, and 28th day after deflasking, and digitalized. Three dimensional deformation patterns were acquired by comparison of the data within storage group using surface matching program. For evaluating differences between groups, these data were compared statisticallyusing Kruskal Wallis and Mann Whitney-U test (α=.05). RESULTS When evaluating 3D deformation of denture base, obvious deformations were not found in maxillary and mandibular water storage group. However, in dry stored group, typical deformation pattern was detected as storage time passes. It occurred mostly in first two weeks. Major deformations were found in the bilateral posterior area in both maxillary and mandibular group. In maxillary dry stored group, a statistical significance was found. CONCLUSION It was proved that in both upper and lower denture bases, dry storage caused more dimensional deformation than water storage with typical pattern. PMID:27555899

  9. 21 CFR 872.3480 - Polyacrylamide polymer (modified cationic) denture adhesive.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... denture retention and comfort. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to be filed with the Food and... (modified cationic) denture adhesive shall have an approved PMA or a declared completed PDP in effect...

  10. 21 CFR 872.3480 - Polyacrylamide polymer (modified cationic) denture adhesive.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... denture retention and comfort. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. A PMA or a notice of completion of a PDP is required to be filed with the Food and... (modified cationic) denture adhesive shall have an approved PMA or a declared completed PDP in effect...

  11. 21 CFR 872.3480 - Polyacrylamide polymer (modified cationic) denture adhesive.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... adhesive. 872.3480 Section 872.3480 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... polymer (modified cationic) denture adhesive. (a) Identification. A polyacrylamide polymer (modified cationic) denture adhesive is a device composed of polyacrylamide polymer (modified cationic) intended...

  12. 21 CFR 872.3480 - Polyacrylamide polymer (modified cationic) denture adhesive.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... adhesive. 872.3480 Section 872.3480 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... polymer (modified cationic) denture adhesive. (a) Identification. A polyacrylamide polymer (modified cationic) denture adhesive is a device composed of polyacrylamide polymer (modified cationic) intended...

  13. 21 CFR 872.3480 - Polyacrylamide polymer (modified cationic) denture adhesive.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... adhesive. 872.3480 Section 872.3480 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... polymer (modified cationic) denture adhesive. (a) Identification. A polyacrylamide polymer (modified cationic) denture adhesive is a device composed of polyacrylamide polymer (modified cationic) intended...

  14. 21 CFR 872.3450 - Ethylene oxide homopolymer and/or karaya denture adhesive.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... adhesive. 872.3450 Section 872.3450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... homopolymer and/or karaya denture adhesive. (a) Identification. Ethylene oxide homopolymer and/or karaya denture adhesive is a device composed of ethylene oxide homopolymer and/or karaya intended to be...

  15. 21 CFR 872.3450 - Ethylene oxide homopolymer and/or karaya denture adhesive.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... adhesive. 872.3450 Section 872.3450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... homopolymer and/or karaya denture adhesive. (a) Identification. Ethylene oxide homopolymer and/or karaya denture adhesive is a device composed of ethylene oxide homopolymer and/or karaya intended to be...

  16. 21 CFR 872.3400 - Karaya and sodium borate with or without acacia denture adhesive.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Karaya and sodium borate with or without acacia... and sodium borate with or without acacia denture adhesive. (a) Identification. A karaya and sodium borate with or without acacia denture adhesive is a device composed of karaya and sodium borate with...

  17. 21 CFR 872.3400 - Karaya and sodium borate with or without acacia denture adhesive.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Karaya and sodium borate with or without acacia... and sodium borate with or without acacia denture adhesive. (a) Identification. A karaya and sodium borate with or without acacia denture adhesive is a device composed of karaya and sodium borate with...

  18. 21 CFR 872.3400 - Karaya and sodium borate with or without acacia denture adhesive.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Karaya and sodium borate with or without acacia... and sodium borate with or without acacia denture adhesive. (a) Identification. A karaya and sodium borate with or without acacia denture adhesive is a device composed of karaya and sodium borate with...

  19. 21 CFR 872.3450 - Ethylene oxide homopolymer and/or karaya denture adhesive.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... adhesive. 872.3450 Section 872.3450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... homopolymer and/or karaya denture adhesive. (a) Identification. Ethylene oxide homopolymer and/or karaya denture adhesive is a device composed of ethylene oxide homopolymer and/or karaya intended to be...

  20. 21 CFR 872.3450 - Ethylene oxide homopolymer and/or karaya denture adhesive.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... adhesive. 872.3450 Section 872.3450 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... homopolymer and/or karaya denture adhesive. (a) Identification. Ethylene oxide homopolymer and/or karaya denture adhesive is a device composed of ethylene oxide homopolymer and/or karaya intended to be...

  1. 21 CFR 872.3760 - Denture relining, repairing, or rebasing resin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Denture relining, repairing, or rebasing resin. 872.3760 Section 872.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3760 Denture...

  2. 21 CFR 872.3760 - Denture relining, repairing, or rebasing resin.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Denture relining, repairing, or rebasing resin. 872.3760 Section 872.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3760 Denture...

  3. 21 CFR 872.3760 - Denture relining, repairing, or rebasing resin.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Denture relining, repairing, or rebasing resin. 872.3760 Section 872.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3760 Denture...

  4. 21 CFR 872.3760 - Denture relining, repairing, or rebasing resin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Denture relining, repairing, or rebasing resin. 872.3760 Section 872.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3760 Denture...

  5. VINEGAR AS AN ANTIMICROBIAL AGENT FOR CONTROL OF Candida spp. IN COMPLETE DENTURE WEARERS

    PubMed Central

    Pinto, Telma Maria Silva; Neves, Ana Christina Claro; Leão, Mariella Vieira Pereira; Jorge, Antonio Olavo Cardoso

    2008-01-01

    The use of denture is known to increase the carriage of Candida in healthy patients, and the proliferation of Candida albicans strains can be associated with denture-induced stomatitis. The aim of this study was to evaluate the use of vinegar as an antimicrobial agent for control of Candida spp. in complete upper denture wearers. Fifty-five patients were submitted to a detailed clinical interview and oral clinical examination, and were instructed to keep their dentures immersed in a 10% vinegar solution (pH less than 3) overnight for 45 days. Before and after the experimental period, saliva samples were collected for detection of Candida, counting of cfu/mL and identification of species by phenotypical tests (germ tube formation, chlamidoconidia production, and carbohydrate fermentation and assimilation). The results were analyzed using Spearman's correlation and Student's t-test (p≤0.05). Candida yeasts were present in 87.3% of saliva samples before the treatment. A significant reduction was verified in CFU/mL counts of Candida after treatment. A positive correlation between Candida and denture stomatitis was verified, since the decrease of cfu/mL counts was correlated with a reduction in cases of denture stomatitis. Although it was not able to eliminate C. albicans, the immersion of the complete denture in 10% vinegar solution, during the night, reduced the amounts (cfu/mL) of Candida spp. in the saliva and the presence of denture stomatitis in the studied patients. PMID:19082396

  6. Evaluation of chitosan quaternary ammonium salt-modified resin denture base material.

    PubMed

    Song, Rong; Zhong, Zhaohua; Lin, Lexun

    2016-04-01

    Chitosan quaternary ammonium salt displays good antioxidant and antibacterial characteristics and it shows appreciable solubility in water. When added to the traditional denture material to form a resin base, it could promote good oral health by improving the oral environment. In this study, chitosan quaternary ammonium salt was added to the denture material following two different methods. After three months of immersion in artificial saliva, the specimens were tested for tensile strength and were scanned by electron microscope. The murine fibroblast cytotoxicity and antibacterial properties were also tested. The result showed no significant differences in the tensile strength and in the proliferation of murine L929 fibroblast cells. The two structures of chitosan quaternary ammonium salt-modified denture material had different degrees of corrosion resistance and antimicrobial properties. These results indicate that chitosan quaternary ammonium salt-modified resin denture base material has the potential to become a new generation oral denture composite material. PMID:26718869

  7. 2D barcodes: a novel and simple method for denture identification.

    PubMed

    Sudheendra, Udyavara S; Sowmya, Kasetty; Vidhi, Mathur; Shreenivas, Kallianpur; Prathamesh, Joshi

    2013-01-01

    Several methods of denture marking have been described in the literature. However, most of them are expensive, time-consuming, and do not permit the incorporation of large amounts of information. We propose a novel and simple method incorporating 2D codes which has several advantages over the existing methods. A 2D code was generated in the dental office and inserted into a maxillary denture. The code was then read using software downloaded into a mobile phone giving access to the website containing details about the patient. The denture was also subjected to durability tests, which did not hamper the efficacy of the 2D code. 2D coding for dentures is a simple, less expensive method with the potential of storing a large amount of information that can be accessed on-site by the forensic investigator, thus allowing quick identification of the denture wearer. PMID:22971078

  8. Retention of denture bases fabricated by three different processing techniques – An in vivo study

    PubMed Central

    Chalapathi Kumar, V. H.; Surapaneni, Hemchand; Ravikiran, V.; Chandra, B. Sarat; Balusu, Srilatha; Reddy, V. Naveen

    2016-01-01

    Aim: Distortion due to Polymerization shrinkage compromises the retention. To evaluate the amount of retention of denture bases fabricated by conventional, anchorized, and injection molding polymerization techniques. Materials and Methods: Ten completely edentulous patients were selected, impressions were made, and master cast obtained was duplicated to fabricate denture bases by three polymerization techniques. Loop was attached to the finished denture bases to estimate the force required to dislodge them by retention apparatus. Readings were subjected to nonparametric Friedman two-way analysis of variance followed by Bonferroni correction methods and Wilcoxon matched-pairs signed-ranks test. Results: Denture bases fabricated by injection molding (3740 g), anchorized techniques (2913 g) recorded greater retention values than conventional technique (2468 g). Significant difference was seen between these techniques. Conclusions: Denture bases obtained by injection molding polymerization technique exhibited maximum retention, followed by anchorized technique, and least retention was seen in conventional molding technique. PMID:27382542

  9. A Clinical Study to Examine the Effect of Complete Denture on Head Posture/Craniovertical Angle

    PubMed Central

    Nandeeshwar, D.B.; Sangur, Rajashekar; Makkar, Sumit; Khare, Pooja; Chitumalla, Rajkiran; Prasad, Renuka

    2016-01-01

    Introduction Edentulous patients show some significant changes in ridge relationship caused by resorption of alveolar ridge. The changes are characterized by an upward rotation of mandible, increase in mandibular prognathism that ultimately results in change of natural head posture. Aim This clinical study was planned to know the effect of complete denture on head posture in different age groups of Indian completely edentulous population, after placement of complete denture at various time intervals. Materials and Methods The sample consisted of completely edentulous patients without previous experience of the dentures. They were divided into 2 age groups: Group A (45-60) and Group B (61-75). During placement of complete denture craniovertical angle was measured with the help of custom made ruler protector device. Readings were taken before denture placement, immediately after denture placement, 30 minutes, 24 hours and 30 days after dentures placement. Results The results of this study indicated that in most of the patients (90%) despite their age, change in head posture (extension) occurred immediately after the denture placement. Thereafter reading remains same for measurement at 30 minutes and 24 hours of denture placement. However after 30 days, observation revealed that all the patients showed reduced craniovertical angle (flexion). Even though the values of craniovertical angle remain higher than its baseline in both groups, significant changes were noticed only in Group A. Conclusion Findings revealed that head posture was significantly altered by the placement of dentures in completely edentulous patients. Within the time interval of 30 minutes and 24 hours extension of head posture remained constant with slight variation. Although after 30 days, changes remained significant for group ‘A’, but no significant changes were observed in the subjects of group ‘B’. PMID:27190938

  10. Further observations on high impact strength denture-base materials.

    PubMed

    Rodford, R A; Braden, M

    1992-01-01

    Previous studies have shown that high impact strength can be conferred on denture-base poly(methyl methacrylate) polymers by modification with acrylic-terminated butadiene-styrene block copolymers, and that the acrylic end-group was necessary for effective reinforcement. It is now shown that, by solvent extraction studies, grafting of the copolymer occurs both with acrylic-terminated and non-terminated block copolymers. It is therefore concluded that the mode of grafting is different, and some possible mechanisms are discussed. PMID:1420720

  11. Inhibitory Effect of Alpha-Mangostin on Adhesion of Candida albicans to Denture Acrylic

    PubMed Central

    Kaomongkolgit, Ruchadaporn; Jamdee, Kusuma

    2015-01-01

    Objective: Candida-associated denture stomatitis is a very common disease affecting denture wearers. It is characterized by the presence of yeast biofilm on the denture, primarily associated with C. albicans. The investigation of agents that can reduce C. albicans adhesion may represent a significant advancement in the prevention and treatment of this disease. This study aims to investigate the effect of alpha-mangostin on the in vitro adhesion of C. albicans to denture acrylic and germ tube formation by C. albicans and to compare its activity with clotrimazole which is a topical antifungal agent commonly used for the treatment of Candida-associated denture stomatitis. Materials and Methodology: Alpha-mangostin was extracted by thin layer chromatography. The effect of alpha-mangostin on adhesion of C. albicans to denture acrylic was determined by using a colorimetric tetrazolium assay and germ tube formation by C. albicans was determined by using the counting chamber. Results: A significant reduction of C. albicans adhesion to denture acrylic was evident after exposure to 2,000 µg/ml of alpha-mangostin for only 15 min. In addition, the 2,000 µg/ml of the alpha-mangostin-treated C. albicans had a reduced ability for germ tube formation. These inhibitory effects of alpha-mangostin were as effective as clotrimazole. Conclusion: Alpha-mangostin has antifungal property against C. albicans by inhibiting the adhesion to denture acrylic and germ tube formation in vitro. These results suggest the potential application of alpha-mangostin as a topical medication or a natural oral hygiene product for treatment of Candida-associated denture stomatitis. PMID:26962371

  12. Effectiveness of Photodynamic Therapy for the Inactivation of Candida spp. on Dentures: In Vitro Study

    PubMed Central

    Mima, Ewerton Garcia de Oliveira; Ribeiro, Daniela Garcia; Dovigo, Livia Nordi; Vergani, Carlos Eduardo; Bagnato, Vanderlei Salvador

    2011-01-01

    Abstract Objective: This in vitro study evaluated the effectiveness of photodynamic therapy (PDT) for the inactivation of different species of Candida on maxillary complete dentures. Background data: The treatment of denture stomatitis requires the inactivation of Candida spp. on dentures. PDT has been reported as an effective method for Candida inactivation. Methods: Reference strains of C. albicans, C. glabrata, C. tropicalis, C. dubliniensis and C. krusei were tested. Thirty-four dentures were fabricated in a standardized procedure and subjected to ethylene oxide sterilization. The dentures were individually inoculated with one of the strains and incubated at 37°C for 24 h. Dentures submitted to PDT (P+L+) were individually sprayed with 50 mg/L of Photogem® (PS) and, after 30 min, illuminated by LED light for 26 min (37.5 J/cm2). Additional dentures were treated only with PS (P+L-) or light (P-L+) or neither (P-L-). Samples of serial dilutions were spread on Sabouraud dextrose agar and incubated at 37°C for 48 h. The colonies were counted and the values of log (cfu/mL) were analyzed by Kruskall-Wallis and Dunn tests (p<0.05). Results: For all species of Candida, PDT resulted in significant reduction (p<0.05) of cfu/mL values from dentures when compared with P-L- (reductions from 1.73 to 3.99 log10). Significant differences (p<0.05), but lower reductions, were also observed for P+L- and P-L+when compared with P-L- for some species of Candida. Conclusions: PDT was an effective method for reducing Candida spp. on dentures. PMID:21916614

  13. Effect of silica coating and silane surface treatment on the bond strength of soft denture liner to denture base material

    PubMed Central

    ATSÜ, Saadet; KESKİN, Yasemin

    2013-01-01

    Objective This study investigated the effects of different surface treatments on the tensile bond strength of an autopolymerizing silicone denture liner to a denture base material after thermocycling. Material and Methods Fifty rectangular heat-polymerized acrylic resin (QC-20) specimens consisting of a set of 2 acrylic blocks were used in the tensile test. Specimens were divided into 5 test groups (n=10) according to the bonding surface treatment as follows: Group A, adhesive treatment (Ufi Gel P adhesive) (control); Group S, sandblasting using 50-µm Al2O3; Group SCSIL, silica coating using 30-µm Al2O3 modified by silica and silanized with silane agent (CoJet System); Group SCA, silica coating and adhesive application; Group SCSILA, silica coating, silane and adhesive treatment. The 2 PMMA blocks were placed into molds and the soft lining materials (Ufi Gel P) were packed into the space and polymerized. All specimens were thermocycled (5,000 cycles) before the tensile test. Bond strength data were analyzed using 1-way ANOVA and Duncan tests. Fracture surfaces were observed by scanning electron microscopy. X-ray photoelectron spectrometer (XPS) and Fourier Transform Infrared spectrometer (FTIR) analysis were used for the chemical analysis and a profilometer was used for the roughness of the sample surfaces. Results The highest bond strength test value was observed for Group A (1.35±0.13); the lowest value was for Group S (0.28±0.07) and Group SCSIL (0.34±0.03). Mixed and cohesive type failures were seen in Group A, SCA and SCSILA. Group S and SCSIL showed the least silicone integrations and the roughest surfaces. Conclusion Sandblasting, silica coating and silane surface treatments of the denture base resin did not increase the bond strength of the silicone based soft liner. However, in this study, the chemical analysis and surface profilometer provided interesting insights about the bonding mechanism between the denture base resin and silicone soft liner

  14. Forces required by complete dentures for penetrating food in simulated function.

    PubMed

    Eerikäinen, E; Könönen, M

    1987-11-01

    Forces required by complete dentures for penetrating some commonly used food items were measured experimentally. These forces were compared with the maximal bite forces of twenty-seven complete denture wearers. Food items that required the greatest forces in direct closure were rye bread (167 N), raw carrot (118 N), boiled meat (80 N), and raw cabbage (74 N). Raw carrot and raw cabbage required the greatest force in straight incision (39 N and 33 N, respectively). Simulated laterotrusion aided most in the penetration of rye bread and boiled meat. The penetration forces in simulated conditions were high compared with the maximal bite forces of the complete denture wearers. PMID:3481400

  15. Attachment of Candida albicans to denture base acrylic resin processed by three different methods.

    PubMed

    Young, Beth; Jose, Anto; Cameron, Donald; McCord, Fraser; Murray, Colin; Bagg, Jeremy; Ramage, Gordon

    2009-01-01

    Denture stomatitis is a debilitating disease associated with the presence of adherent Candida albicans. This study compared the attachment capacity of C. albicans to three different acrylic resin materials (self-curing [SC], conventional pressure-packed [CPP], and injection-molded [IM]) to determine whether the physical properties of the materials influenced candidal attachment. No significant differences in attachment between the isolates were observed for each acrylic resin. However, a comparison of the mean of all isolates showed significantly less attachment to SC than to CPP (P < .05). These data indicate that choice of denture acrylic resin material may influence the capacity for developing denture stomatitis. PMID:20095199

  16. Fibres reinforced dentures investigated with en-face optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Negrutiu, Meda L.; Sinescu, Cosmin; Hughes, Michael; Bradu, Adrian; Goguta, Luciana; Rominu, Mihai; Negru, Radu; Podoleanu, Adrian Gh.

    2008-04-01

    The complete dentures are currently made using different technologies. In order to avoid deficiencies of the prostheses made using the classical technique, several alternative procedures have been devised. In order to enhance the mechanical strength, complete denture bases are reinforced with fibres. Their material and structure vary wildly, which makes the investigation difficult. In this study, optical coherence tomography (OCT) is evaluated as a possible non-invasive technique to assess the biomechanical behaviour of the reinforcing fibres. OCT images demonstrate structural defects between fibres and the acrylic material in all dentures bases investigated. We conclude that OCT can successfully be used as a noninvasive analysis method.

  17. A Comparison of Masticatory Performance and Efficiency of Complete Dentures Made with High Impact and Flexible Resins: A Pilot Study

    PubMed Central

    Bhoyar, Anjali; Mishra, Sunil Kumar; Yadav, Naveen S.; Mahajan, Harsh

    2015-01-01

    Background In patients with extensive tooth loss, restoration of masticatory function and aesthetics is main concern for a prosthodontist. Aim of Study This study aimed to evaluate and compare differences in masticatory efficiency of patients treated with complete dentures made with either high impact or flexible resins. Setting and Design The sample size consisted of 10 study subjects. Two sets of dentures first conventional followed by flexible dentures were fabricated for each subject and both the sets of dentures were accessed for masticatory performance and efficiency. Materials and Methods This study compared the masticatory performance and efficiency of dentures by means of standardized mesh sieves. Masticatory efficiency was calculated by recording the total number of chewing cycles and time required to completely swallow a standardized food item. A patient satisfaction questionnaire was given and evaluated. Statistical Analysis Used The statistical analyses were performed using Z-test of Proportion and Paired t-test. Results The masticatory performance ratio was found to be more for hard food in conventional dentures. The values of masticatory performance ratios for soft food, time and number of masticatory strokes were indicating better masticatory efficiency of conventional dentures. Conclusion Though masticatory efficiency and performance were found to be better for patient’s dentures made with Polymethyl methacrylate (PMMA), a statistically significant number of patients reported that the flexible dentures were more satisfying than the conventional dentures. PMID:26266213

  18. [The implant denture in the laboratory].

    PubMed

    Scortecci, G M; Crousillat, J; Foesser, P; Bourbon, B

    1989-09-01

    The authors analyzed the numerous devices and prosthetic kits currently available for implant prosthodontics. Existing systems can be classified into two fundamentally different categories: the gold ring cylinder (or its equivalent in resin for casting) and the prosthetic abutment core or post concept. The former is based on connection of two nearly flat, horizontal surfaces by means of a screw, which avoids problems of parallelism; the latter can be likened to insertion of one part into another, like a crown that slides along the vertical axis of an abutment, with connection being obtained by cementation and/or screwing. Prosthetic abutment core or post: Whether monoblock or multiblock, the implant core or post is very similar to a conventional metallic abutment. Construction of the implant prosthesis is generally no problem when parallelism has been respected during surgery; if problems are encountered with parallelism, options include: 1. Adjustment of the abutment core by grinding, 2. Use of a telescope to achieve parallelism, 3. Use of a bendable prosthetic abutment core, 4. Use of a prosthetic abutment core preangulated 10 degrees-20 degrees, 5. A combination of the above solutions. The implant prostheses may be screwed, cemented or clipped in position. Gold ring cylinder concept The gold ring cylinder (or its equivalent in resin for casting) theoretically eliminates problems of parallelism, but at the same time restricts the implant prosthesis to screw techniques. A special protocol is required for the impression and construction of the prosthesis. Impression with plaster is often the best method for total edentulism whereas "open" impression trays are advisable for partial prostheses. In the laboratory, use of a machined gold ring cylinder provides optimum precision, but intra-oral verification remains necessary. Implant prosthodontics unquestionably represent a new type of "know how": both the dentist and the dental lab technician must acquire the

  19. Creep and stress relaxation behavior of two soft denture liners.

    PubMed

    Salloum, Alaa'a M

    2014-03-01

    Numerous investigators stated the indications of soft denture lining materials; but no one determined the indications of these materials according to their chemical structure. The purpose of this investigation was to evaluate the viscoelastic properties of acrylic and silicon lining materials. This study investigated and compared viscoelastic properties of two resilient denture lining materials. Tested materials were laboratory processed; one of them was silicone-based liner product (Molloplast-B), and the other was plasticized acrylic resin (Vertex™ Soft). Twenty cylindrical specimens (10-20 mm in length, 11.55 mm in diameter) were fabricated in an aluminum mold from each material for creep and stress relaxation testing (the study of viscoelastic properties). Tests were performed by using the universal testing machine DY-34. Collected data were analyzed with t test statistics for statistically significant differences at the 95 % confidence level. There was a clear difference in creep and stress relaxation behavior between acrylic and silicone liners. Statistical study of Young's moduli illustrated that Vertex™ Soft was softer than Molloplast-B. On the other hand, the results explained that the recovery of silicone material was better than of acrylic one. The creep test revealed that the plasticized acrylic resin lining material exhibited considerable creep, whereas silicone-based liner exhibited elastic behavior. Besides, the stress relaxation test showed that relaxation of the plasticized acrylic resin material was bigger than of the silicone-based liner. PMID:24605004

  20. Mechanical evaluation and fem analysis of stress in fixed partial dentures zirconium-ceramic

    PubMed Central

    CARDELLI, P.L.; VERTUCCI, V.; BALESTRA, F.; MONTANI, M.; ARCURI, C.

    2013-01-01

    SUMMARY Objective. Over the last several years, the Finite Element Analysis (FEM) has been widely recognized as a reference method in different fields of study, to simulate the distribution of mechanical stress, in order to evaluate the relative distribution of loads of different nature. The aim of this study is to investigate through the FEM analysis the stress distribution in fixed prostheses that have a core in Zirconia and a ceramic veneer supported by implants. Materials and methods. In this work we investigated the mechanical flexural strength of a ceramic material (Noritake®) and a of zirconium framework (Zircodent®) and the effects of the manufacturing processes of the material commonly performed during the production of fixed prostheses with CAD/CAM technology. Specifically three point bending mechanical tests were performed (three-point-bending) (1–3), using a machine from Test Equipment Instron 5566®, on two structures in zirconium framework-ceramic (structures supported by two implant abutments with pontic elements 1 and 2). A further in-depth analysis on the mechanical behavior in flexure of the specimens was conducted carrying out FEM studies in order to compare analog and digital data. Results. The analysis of the data obtained showed that the stresses are distributed in a different way according to the intrinsic elasticity of the structure. The analysis of FPD with four elements, the stresses are mainly concentrated on the surface of the load, while, in the FPD of three elements, much more rigid, the stresses are concentrated near the inner margins of the abutments. The concentration of many stresses in this point could be correlated to chipping (4) that is found in the outer edges of the structure, as a direct result of the ceramic brittleness which opposes the resilience of the structure subjected to bending. Conclusions. The analysis of the UY linear displacement confirms previous data, showing, in a numerical way, that the presence of the ceramic is related to the lowering of the structure. So, the reference values are those of the linear lowering obtained in the Mechanical Test and in our FEM analysis. zirconium framework with four elements 4,227 10−2mm.zirconium framework with ceramic structure with four elements 2,266 10−2 mm.That suggests that the presence of ceramics halves the flexion capabilities of the prosthetic materials. PMID:24772262

  1. Indications and potential of bonded metal-ceramic fixed partial dentures.

    PubMed

    Dietschi, D

    2000-01-01

    Recent progress in restorative dentistry has dramatically modified contemporary treatment concepts, which are typified by the preservation of healthy tissues, recognition of aesthetic expectations, and the search for simplified prosthetic solutions. While this shift in focus has justified the increasing interest in implantology, it has also resulted in the expansion of adhesive and conservative treatment options. This article reviews the various means available to replace missing anterior teeth, as well as the periodontal and surgical procedures that are associated with the optimization of biological, functional, and aesthetic results. PMID:11404891

  2. Fixed partial dentures on two implants: raising comfort in irradiated edentulous patients.

    PubMed

    Meijer, G J; Mel, P; Koole, R; Cune, M S

    2007-07-01

    Surgical treatment of malignancies involving the oral cavity often results in an altered anatomical situation, which may severely hamper oral function. Postoperative radiotherapy resulting in reduced salivary secretion further worsens functions such as speech, chewing (mastication) and swallowing. In order to improve oral functioning, the use of dental implants was proposed. To reconstruct the edentulous mandible, especially in cases involving postoperative irradiation, implant-borne prosthetic construction on four permucosal implants has been advocated, but this treatment concept has some practical drawbacks. As the chewing force is reduced as a result of irradiation of the masticatory muscles, it is hypothesized that a fixed prosthetic construction on only two implants is a feasible alternative. Up until now 10 patients have been treated successfully according to this concept at the authors' clinic. PMID:17418533

  3. The effect of relining on the accuracy and stability of maxillary complete dentures--an in vitro and in vivo study.

    PubMed

    Barco, M T; Moore, B K; Swartz, M L; Boone, M E; Dykema, R W; Phillips, R W

    1979-07-01

    A technique was developed for evaluating in vitro the accuracy or fit of experimental denture bases using a low-viscosity impression material for determining the space between the master die and the processed denture base. These measurements indicated that relining heat-cured maxillary denture bases with autopolymerizing acrylic resin improved their adaptation to the ridges. Interestingly, if no teeth were present in the heat-cured denture base, markedly less distortion occurred after processing. Limited clinical measurements on the stability of maxillary dentures in function showed no statistically significant change in stability after relining, but the trend was toward increased stability with the relined denture. PMID:379306

  4. Impact absorption of four processed soft denture liners as influenced by accelerated aging.

    PubMed

    Kawano, F; Koran, A; Nuryanti, A; Inoue, S

    1997-01-01

    The cushioning effect of soft denture liners was evaluated by using a free drop test with an accelerometer. Materials tested included SuperSoft (Coe Laboratories, Chicago, IL), Kurepeet-Dough (Kreha Chemical, Tokyo), Molteno Soft (Molten, Hiroshima, Japan), and Molloplast-B (Molloplast Regneri, Karlsruhe, Germany). All materials were found to reduce the impact force when compared to acrylic denture base resin. A 2.4-mm layer of soft denture material demonstrated good impact absorption, and Molloplast-B and Molteno had excellent impact absorption. When the soft denture liner was kept in an accelerated aging chamber for 900 hours, the damping effect recorded increased for all materials tested. Aging of all materials also affected the cushioning effect. PMID:9484071

  5. Long-term follow-up of conical crown-retained dentures fabricated using different technologies.

    PubMed

    Pietruski, Jan K; Pietruska, Malgorzata D; Sajewicz, Eugeniusz

    2012-08-01

    This study presents the results of a long-term clinical evaluation of conical crown-retained dentures fabricated using different technologies. Four different material connections between the outer and inner crowns were used: cast gold/cast gold, cast gold/electroforming, nonprecious alloy/electroforming, and titanium abutment/electroforming. Technical failures and retention values were assessed. The best clinical outcome was found with dentures in which both crowns were cast from gold alloy. The most frequent technical failures were observed in restorations with electroformed outer crowns. Better clinical outcomes were noted when the electroformed outer crowns were used in dentures retained by implants as compared to dentures on natural dentition. PMID:22577653

  6. 21 CFR 872.3420 - Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... comfort. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. A PMA... carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive shall have an approved PMA or...

  7. 21 CFR 872.3420 - Carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... comfort. (b) Classification. Class III. (c) Date PMA or notice of completion of a PDP is required. A PMA... carboxymethylcellulose sodium and cationic polyacrylamide polymer denture adhesive shall have an approved PMA or...

  8. A simple and inexpensive bar-coding technique for denture identification

    PubMed Central

    Nalawade, Sonali N; Lagdive, Sanjay B; Gangadhar, SA; Bhandari, Aruna J

    2011-01-01

    A number of commercial methods for identifying dentures are available. They can be either invasive or noninvasive techniques. The less sophisticated procedures include simple engraving with bur, and more sophisticated procedures use labels or chips. Bar coding system is a way of transferring data to the computer and huge data can be stored as a record. Bar coding can be easily incorporated during acrylization of the denture and thus could be used in individual identification. PMID:22408329

  9. [Use of the Preci-Horix attachment in anchoring an overlay denture].

    PubMed

    Palkovics, G; Andics, L

    1989-08-01

    In the case report the overdenture prosthesis replacing the subtotal edentulousness is fixed by a Preci-Horix anchorage of individual design built on the tooth roots. The matrix portion of the anchorage was built in situ into the tooth plate of the denture. This aimes at preventing the disadvantageous overloading effect of the position change due to initial sinking of the denture on the support tooth. PMID:2673846

  10. A simple and inexpensive bar-coding technique for denture identification.

    PubMed

    Nalawade, Sonali N; Lagdive, Sanjay B; Gangadhar, Sa; Bhandari, Aruna J

    2011-07-01

    A number of commercial methods for identifying dentures are available. They can be either invasive or noninvasive techniques. The less sophisticated procedures include simple engraving with bur, and more sophisticated procedures use labels or chips. Bar coding system is a way of transferring data to the computer and huge data can be stored as a record. Bar coding can be easily incorporated during acrylization of the denture and thus could be used in individual identification. PMID:22408329

  11. Effect of cross-linking on sorption properties of a denture-base material.

    PubMed

    Jagger, R G; Huggett, R

    1990-10-01

    Cross-linking of the polymer of the interstitial matrix of a heat-cured resin denture base is said to provide craze resistance for the denture base. The mechanism of crazing can be related to both water sorption and solvent attack. The present study shows that the addition of ethylene glycol dimethacrylate in concentrations of 0-100% of monomer volume has little effect on water sorption properties but is an efficient method of providing solvent resistance. PMID:2086306

  12. Full Mouth Oral Rehabilitation by Maxillary Implant Supported Hybrid Denture Employing a Fiber Reinforced Material Instead of Conventional PMMA

    PubMed Central

    Qamheya, Ala Hassan A.; Yeniyol, Sinem; Arısan, Volkan

    2015-01-01

    Many people have life-long problems with their dentures, such as difficulties with speaking and eating, loose denture, and sore mouth syndrome. The evolution of dental implant supported prosthesis gives these patients normal healthy life for their functional and esthetic advantages. This case report presents the fabrication of maxillary implant supported hybrid prosthesis by using Nanofilled Composite (NFC) material in teeth construction to rehabilitate a complete denture wearer patient. PMID:26557392

  13. The qualitative assessment of complete dentures produced by commercial dental laboratories.

    PubMed

    Barsby, M J; Hellyer, P H; Schwarz, W D

    1995-07-22

    Comprehensive criteria and simple methods of assessment have been developed for the evaluation of complete dentures supplied by commercial dental laboratories. One hundred laboratories in England and Wales were selected by random sampling. A single identical complete denture case was sent from general practice addresses to each of the selected laboratories and each of the laboratory stages evaluated according to specific criteria. This paper is concerned only with the evaluation of the finished dentures. Half of the cases were treated as NHS cases and half as 'private' cases. The private cases were further subdivided into those where details were left to the laboratory and those where detailed instructions were given for all stages of denture construction. Wide variations were found in both the quality and cost of complete denture laboratory work. Evaluation of some key features of finished dentures suggests that the quality of work was superior for the private cases in which detailed instructions were given to the laboratory. Even for the private (specified) cases, however, important faults were found in a number of cases. PMID:7632481

  14. Characterization and bacterial anti-adherent effect on modified PMMA denture acrylic resin containing platinum nanoparticles

    PubMed Central

    2014-01-01

    PURPOSE This study characterized the synthesis of a modified PMMA (Polymethyl methacrylate) denture acrylic loading platinum nanoparticles (PtN) and assessed its bacterial inhibitory efficacy to produce novel antimicrobial denture base material. MATERIALS AND METHODS Polymerized PMMA denture acrylic disc (20 mm × 2 mm) specimens containing 0 (control), 10, 50, 100 and 200 mg/L of PtN were fabricated respectively. The obtained platinum-PMMA nanocomposite (PtNC) was characterized by TEM (transmission electron microscopy), SEM/EDX (scanning electron microscope/energy dispersive X-ray spectroscopy), thermogravimetric and atomic absorption spectrophotometer analysis. In antimicrobial assay, specimens were placed on the cell culture plate, and 100 µL of microbial suspensions of S. mutans (Streptococcus mutans) and S. sobrinus (Streptococcus sobrinus) were inoculated then incubated at 37℃ for 24 hours. The bacterial attachment was tested by FACS (fluorescence-activated cell sorting) analysis after staining with fluorescent probe. RESULTS PtN were successfully loaded and uniformly immobilized into PMMA denture acrylic with a proper thermal stability and similar surface morphology as compared to control. PtNC expressed significant bacterial anti-adherent effect rather than bactericidal effect above 50 mg/L PtN loaded when compared to pristine PMMA (P=.01) with no or extremely small amounts of Pt ion eluted. CONCLUSION This is the first report on the synthesis and its antibacterial activity of Pt-PMMA nanocomposite. PMMA denture acrylic loading PtN could be a possible intrinsic antimicrobial denture material with proper mechanical characteristics, meeting those specified for denture bases. For clinical application, future studies including biocompatibility, color stability and warranting the long-term effect were still required. PMID:25006385

  15. Color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for non metal clasp denture

    PubMed Central

    Jang, Dae-Eun; Lee, Ji-Young; Jang, Hyun-Seon; Lee, Jang-Jae

    2015-01-01

    PURPOSE The aim of this study was to compare the color stability, water sorption and cytotoxicity of thermoplastic acrylic resin for the non-metal clasp dentures to those of thermoplastic polyamide and conventional heat-polymerized denture base resins. MATERIALS AND METHODS Three types of denture base resin, which are conventional heat-polymerized acrylic resin (Paladent 20), thermoplastic polyamide resin (Bio Tone), thermoplastic acrylic resin (Acrytone) were used as materials for this study. One hundred five specimens were fabricated. For the color stability test, specimens were immersed in the coffee and green tee for 1 and 8 weeks. Color change was measured by spectrometer. Water sorption was tested after 1 and 8 weeks immersion in the water. For the test of cytotoxicity, cell viability assay was measured and cell attachment was analyzed by FE-SEM. RESULTS All types of denture base resin showed color changes after 1 and 8 weeks immersion. However, there was no significant difference between denture base resins. All specimens showed significant color changes in the coffee than green tee. In water sorption test, thermoplastic acrylic resin showed lower values than conventional heat-polymerized acrylic resin and thermoplastic polyamide resin. Three types of denture base showed low cytotoxicity in cell viability assay. Thermoplastic acrylic resin showed the similar cell attachment but more stable attachment than conventional heat-polymerized acrylic resin. CONCLUSION Thermoplastic acrylic resin for the non-metal clasp denture showed acceptable color stability, water sorption and cytotoxicity. To verify the long stability in the mouth, additional in vitro studies are needed. PMID:26330974

  16. Comparative evaluation of effect of complete denture wears on the flow rate of saliva in both medicated and apparently healthy patients

    PubMed Central

    Sonthalia, Abhay; Chandrasekaran, Arun P.; Mhaske, Sheetal P.; Lau, Mayank; Joshy, V. R.; Attokaran, George

    2016-01-01

    Aim and Objectives: In the denture wearing people, saliva is necessary to create adhesion, cohesion, and surface tension that ultimately leads to the increased retention of the denture. Medications have some influence on the flow rate of saliva and denture retention. The present study evaluates the effect of complete denture wear on the flow rate of saliva in both medicated and apparently healthy patients. Materials and Methods: The participants were 42 edentulous individuals aged 35–70 years requiring complete denture prostheses. The participants were divided into two groups of medicated and unmedicated. Unstimulated whole saliva was collected at 24 h and 3 months after the insertion of new complete dentures in both the groups. The data obtained were analyzed using Student's paired t-test and unpaired t-test. Intergroup changes were compared with unpaired t-test. Intragroup changes were compared with paired t-test using the Statistical Package for Social Sciences, version 22.0. Results: In the unmedicated group, the mean salivary flow rate was high at 24 h after denture insertion when compared to before denture insertion (P = 0.001 VHS). In the medicated group, the observation was highly significant (P = 0.007 HS) 24 h after denture insertion and after 3 months (P = 0.02 S) when compared to before denture insertion. Conclusion: No significant difference in the salivary flow rate was found 3 months after denture insertion when compared to before denture insertion for both the medicated and unmedicated groups. PMID:27382537

  17. Investigation of bonding properties of denture bases to silicone-based soft denture liner immersed in isobutyl methacrylate and 2-hydroxyethyl methacrylate

    PubMed Central

    Tugut, Faik; Mutaf, Burcu; Guney, Umit

    2014-01-01

    PURPOSE The purpose of this study was to investigate the bonding properties of denture bases to silicone-based soft denture liners immersed in isobutyl methacrylate (iBMA) and 2-hydroxyethyl methacrylate (HEMA) for various lengths of time. MATERIALS AND METHODS Polymethyl methacrylate (PMMA) test specimens were fabricated (75 mm in length, 12 mm in diameter at the thickest section, and 7 mm at the thinnest section) and then randomly assigned to five groups (n=15); untreated (Group 1), resilient liner immersed in iBMA for 1 minute (Group 2), resilient liner immersed in iBMA for 3 minutes (Group 3), resilient liner immersed in HEMA for 1 minute (Group 4), and resilient liner immersed in HEMA for 3 minutes (Group 5). The resilient liner specimens were processed between 2 PMMA blocks. Bonding strength of the liners to PMMA was compared by tensile test with a universal testing machine at a crosshead speed of 5 mm/min. Data were evaluated by 1-way ANOVA and post hoc Tukey-Kramer multiple comparisons tests (α=0.05). RESULTS The highest mean value of force was observed in Group 3 specimens. The differences between groups were statistically significant (P<.05), except between Group 1 and Group 4 (P=.063). CONCLUSION Immersion of silicone-based soft denture liners in iBMA for 3 minutes doubled the tensile bond strength between the silicone soft liner and PMMA denture base materials compared to the control group. PMID:24843397

  18. Epilepsy (partial)

    PubMed Central

    2011-01-01

    Introduction About 3% of people will be diagnosed with epilepsy during their lifetime, but about 70% of people with epilepsy eventually go into remission. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of starting antiepileptic drug treatment following a single seizure? What are the effects of drug monotherapy in people with partial epilepsy? What are the effects of additional drug treatments in people with drug-resistant partial epilepsy? What is the risk of relapse in people in remission when withdrawing antiepileptic drugs? What are the effects of behavioural and psychological treatments for people with epilepsy? What are the effects of surgery in people with drug-resistant temporal lobe epilepsy? We searched: Medline, Embase, The Cochrane Library, and other important databases up to July 2009 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 83 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antiepileptic drugs after a single seizure; monotherapy for partial epilepsy using carbamazepine, gabapentin, lamotrigine, levetiracetam, phenobarbital, phenytoin, sodium valproate, or topiramate; addition of second-line drugs for drug-resistant partial epilepsy (allopurinol, eslicarbazepine, gabapentin, lacosamide, lamotrigine, levetiracetam, losigamone, oxcarbazepine, retigabine, tiagabine, topiramate, vigabatrin, or zonisamide); antiepileptic drug withdrawal for people with partial or

  19. Effectiveness of Hexetidine 0.1% in Eliminating Candida albicans Colonizing Dentures: A Randomized Clinical In Vivo Study

    PubMed Central

    Aoun, Georges; Nasseh, Ibrahim; Saadeh, Maria; Cassia, Antoine; Berberi, Antoine

    2015-01-01

    Background: Effective cleaning of dentures is important to maintain a good oral hygiene for patients suffering from denture stomatitis (DS). This study aimed to evaluate the efficacy of hexetidine 0.1% in eliminating C. albicans colonizing dentures. Materials and Methods: A total of 40 denture wearers (18 men, 22 women; age range 40-80 years) with clinical evidence of DS were randomly divided into 2 groups, 1 test, and 1 control. The dentures of the test group were treated by immersion in hexetidine 0.1% while those of the control group were immersed in distilled water. Swab samples from the palatal surfaces of the upper dentures were collected before and after of cleaner use and examined mycologically. Results: Reduction in the number of colony-forming units (CFU) of C. albicans after immersion of the dentures with hexetidine 0.1% was evaluated compared to those of the control group. Conclusion: Hexetidine 0.1% solution tested for the first time as a product of disinfection of the acrylic dentures showed average results after immersion of 8 night hours for 4 days. PMID:26225095

  20. Comparative failure load values of acrylic resin denture teeth bonded to three different heat cure denture base resins: An in vitro study

    PubMed Central

    Phukela, Sumit Singh; Dua, Amit; Dua, Mahima; Sehgal, Varun; Setya, Gaurav; Dhall, Rupinder Singh

    2016-01-01

    Aim and Objectives: Acrylic teeth are used for fabrication of dentures. Debonding of tooth – denture base bond is routine problem in dental practice. The aim of this study was to comparatively evaluate failure load of acrylic resin denture teeth bonded to three different heat resin. Materials and Methods: Four groups were created out of test samples central incisors (11). Group I: Control, whereas Group II, Group III and Group IV were experimental groups modified with diatoric hole, cingulum ledge lock and Teeth modified with both diatoric hole and cingulum ledge lock, respectively. These test specimens with 3 teeth (2 central [11, 21] and 1, lateral [12] incisors) positioned imitating arrangement of teeth in the conventional denture, prepared by three different heat cure materials (DPI, Trevalon, Acralyn-H). A shear load was applied at cingulum of central incisor (11) at 130° to its long axis using universal tester at a cross head speed of 5 mm/min until failure occurred. Failure load test was conducted and statistical analysis was performed using SPSS 16 software package (IBM Company, New York, U.S). Results: Highest failure load was seen in Group IV specimens, prepared by Trevalon but did not significantly differ from that of DPI. Conclusion: The failure load of bonding denture teeth to three different heat cure materials was notably affected by modifications of ridge lap before processing. The specimens with a combination of diatoric hole and cingulum ledge lock, prepared by Trevalon showed highest failure load but did not significantly vary from that of DPI. The control group prepared by Acralyn-H showed lowest failure load but did not significantly differ from that of DPI. PMID:27195221

  1. The impact of polymerization method on tensile bond strength between denture base and acrylic teeth.

    PubMed

    Hashem, Mohamed; Binmgren, Mohammed A; Alsaleem, Samah O; Vellappally, Sajith; Assery, Mansour K; Sukumaran, Anil

    2014-01-01

    Failure of the bond between acrylic teeth and the denture base resin interface is one of the major concern in prosthodontics. The new generation of denture bases that utilize alternate polymerization methods are being introduced in the market. The aim of the study is to evaluate the influence of polymerization methods on bonding quality between the denture base and artificial teeth. Sixty test specimens were prepared (20 in each group) and were polymerized using heat, microwave and visible light curing. The tensile strength was recorded for each of the samples, and the results were analyzed statistically. The light-activated Eclipse™ System showed the highest tensile strength, followed by heat curing. The microwave-cured samples exhibited the least bonding to the acrylic teeth. Within the limitations of this study, it can be concluded that the new generation of light-cured denture bases showed significantly better bonding to acrylic teeth and can be used as an alternative to the conventional heat-polymerized denture base. PMID:25307813

  2. Comparison of flexural strength in three types of denture base resins: An in vitro study

    PubMed Central

    Jaikumar, R. Arun; Karthigeyan, Suma; Ali, Syed Asharf; Naidu, N. Madhulika; Kumar, R. Pradeep; Vijayalakshmi, K.

    2015-01-01

    Aim: The aim of this study was to evaluate whether the flexural strength of a commercially available, heat polymerized acrylic denture base material could be improved using reinforcements. Materials and Methods: A total of 30 specimens (65 mm × 10 mm × 3 mm) were fabricated; the specimens were divided into three groups with 10 specimens each. They were Group 1 - conventional denture base resins, Group 2 - high impact denture base resins, and Group 3 - glass reinforced denture base resins. The specimens were loaded until failure on a three-point bending test machine. An one-way analysis of variance was used to determine statistical differences among the flexural strength of three groups. Data were analyzed by SPSS software version 21.0© (IBM Corporation, Armonk, NY, USA) and the results were obtained. Results: The flexural strength values showed statistically significant differences among experimental groups (P < 0.005). Conclusion: Within the limitations of the study polymethyl methacrylate (PMMA) reinforced with glass fibers showed the highest flexural strength values this was followed by PMMA reinforced with butadiene styrene, and the least strength was observed in the conventional denture base resins. PMID:26538898

  3. Elucidating role of salivary proteins in denture stomatitis using a proteomic approach.

    PubMed

    Bencharit, Sompop; Altarawneh, Sandra K; Baxter, Sarah Schwartz; Carlson, Jim; Ross, Gary F; Border, Michael B; Mack, C Russell; Byrd, Warren C; Dibble, Christopher F; Barros, Silvana; Loewy, Zvi; Offenbacher, Steven

    2012-10-30

    Denture stomatitis (DS) is the most common oral pathology among denture wearers, affecting over one-third of this group. DS is usually associated with C. albicans. However, unlike other oral candidiasis, most DS patients have intact host immunity. The presence of a denture alone is usually sufficient for DS. Saliva and its protein contents can theoretically predispose some denture wearers to DS and others resistant toward DS. Here we proposed for the first time to define salivary proteomic profiles of denture wearers with and without DS. SELDI-TOF/MS analysis suggests that there is a proteomic differentiation among control, localized and generalized DS. Based on initial SELDI-TOF/MS profiling, we further used reversed phase liquid chromatography, MALDI-TOF/MS, and LC-MS/MS to characterize the salivary proteins associated with DS. Nineteen proteins based on SELDI-TOF/MS profiling were found including cystatin-SN, statherin, kininogen-1, desmocollin-2, carbonic anhydrase-6, peptidyl-prolyl cis-trans isomerase A like peptides, cystatin C, and several immunoglobulin fragments. The proteomic content gives evidence of the interaction between host tissue, saliva, and candida. Further examination in larger populations of these proteins may help to gain a better understanding of DS pathological processes and improve DS treatments. PMID:23041753

  4. Edentulousness, Denture Wear and Denture Needs of the Elderly in Rural South India

    PubMed Central

    Ariga, P; Bridgitte, A; Rangarajan, V; Philip, J M

    2012-01-01

    Background: The objectives of this study were to evaluate the prevalence of edentulousness, patient’s perception on dietary changes resulting from tooth loss and to identify the disparity between actual and patient perceived need to replace missing teeth in an elderly rural population in south India. Methods: A cross sectional study using the systematic cluster sampling method was used to select the study sample of 150 elderly men and women. Data were collected using questionnaires and oral examination. The data were statistically analyzed using chi square test and pearson correlation. Results: 15.6% of the rural elderly were completely edentulous and 54.7% were partially edentulous. Observed differences in distribution between the sampled elderly age groups were found to be statistically significant. Although 70.3% of the evaluated elderly actually required prosthodontic treatment, only 14.4% perceived the need to replace missing teeth. A small percentage of the elderly (18%) perceived a severe change in their diets due to tooth loss. Thirty three percent of them perceived a moderate change and 28% felt that there were no dietary changes because of tooth loss. Conclusions: It is essential to identify feasible strategies to provide primary dental health education and treatment to all rural elderly in the future. We suggest community dental health services as a general health need of the elderly rather than a special health need of the community. PMID:23113208

  5. Complete denture base assessments using holograms: dimensional alterations after different activation methods

    NASA Astrophysics Data System (ADS)

    Dughir, Ciprian; Popovschi, Ana Maria; Cojocariu, Andreea Codruta; Topala, Florin Ionel; Negrutiu, Meda Lavinia; Sinescu, Cosmin; de Sabata, Aldo; Duma, Virgil-Florin

    2016-03-01

    Holography is a well-developed method with a large range of applications, including dentistry. This study uses holographic methods for the study of total dental prosthesis. The issue is that the transformation of wax denture base in polymethylacrylate causes dimensional alterations and retractions in the final dental constructs. These could cause the failure of the stability of the complete denture in the oral cavity. Thus, the aim of this study is to determine and to compare using holography, total prosthesis obtained using three different manufacturing methods: pressing, injection, and polymerization. Each of the three types of dentures thus produced were recorded over the previously wax complete base holographic plates. The dimensional alterations that appear after using the different activation methods were thus determined. The most significant modification was remarked in the custom press technology, while the smallest variations were detected in the injection alternative.

  6. Comparative electromyographic study of elevator muscles in patients with complete dentures and natural dentition.

    PubMed

    Miralles, R; Berger, B; Ide, W; Manns, A; Bull, R; Carvajal, A

    1989-05-01

    An analysis of integrated electromyographic (IEMG) activity of masseter and anterior temporal muscles was undertaken in fifteen patients with complete dentures and eight adult subjects with natural dentition. Bipolar surface electrodes were used for IEMG recordings during maximal voluntary clenching and saliva swallowing in the inter-cuspal position. The IEMG activity of both muscles during maximal voluntary clenching was significantly lower in patients with complete dentures than in subjects with natural dentition. During saliva swallowing the activity in both muscles was similar in both groups. This may have a great clinical significance in the maintenance of the functional state of the different structures of the stomatognathic system in complete denture wearers, since the process of swallowing is a 24-h function repeated about 600-2400 times each day. PMID:2746412

  7. Oral squamous cell carcinoma misdiagnosed as a denture-related traumatic ulcer: A clinical report.

    PubMed

    Valente, Vitor Bonetti; Takamiya, Aline Satie; Ferreira, Lígia Lavezo; Felipini, Renata Callestini; Biasoli, Éder Ricardo; Miyahara, Glauco Issamu; Bernabé, Daniel Galera

    2016-03-01

    A 65-year-old woman presented with an ulcerated lesion in the alveolar ridge mucosa, which appeared after new dentures had been inserted. Despite many treatment attempts, the lesion did not recede, even with the interruption of denture wearing. A biopsy was performed, and histopathologic examination revealed an ulcerated, invasive, poorly differentiated oral squamous cell carcinoma. The time from the patient's first contact with the prosthodontist because of the lesion until the appropriate diagnosis was established was approximately 6 months. This clinical report documents a significant delay in the oral squamous cell carcinoma diagnosis and treatment because of a clinical misdiagnosis of a traumatic ulcer resulting from complete dentures. Prosthodontists should be aware of the importance of early diagnosis of oral cancer among elderly prosthesis wearers. PMID:26581660

  8. Comparison of denture base resin reinforced with polyaromatic polyamide fibers of different orientations.

    PubMed

    Yu, Sang-Hui; Ahn, Dae-Hyung; Park, Ji-Su; Chung, Yong Sik; Han, In-Sik; Lim, Jung-Seop; Oh, Seunghan; Oda, Yutaka; Bae, Ji-Myung

    2013-01-01

    The aim of this study was to evaluate the effect of reinforcing polyaromatic polyamide (aramid) fibers with various orientations on the flexural properties of denture base resin. Aramid fibers with four orientations of unidirectional, woven, non-woven and paper-type were pre-impregnated and placed at the bottom of a specimen mold. Heat-polymerized denture base resin was packed over the fibers and polymerized. A three-point bending test was performed using a universal testing machine at a crosshead speed of 5 mm/min. The flexural strengths and flexural moduli of the unidirectional and woven groups were significantly higher than those of the control and other experimental groups.For the flexural moduli, all experimental groups showed significantly higher reinforcing effects than the control group. In conclusion, the unidirectional group located perpendicular to the direction of the load was most effective in reinforcing the denture base resin, followed by the woven group. PMID:23538771

  9. The Pontic-Shield: Partial Extraction Therapy for Ridge Preservation and Pontic Site Development.

    PubMed

    Gluckman, Howard; Du Toit, Jonathan; Salama, Maurice

    2016-01-01

    Augmentive ridge preservation techniques aim to manage the postextraction ridge. The partial extraction of teeth may better preserve the ridge form by maintaining the bundle bone-periodontal ligament apparatus. Root submergence has been demonstrated to retain the periodontal tissues and preserve the ridge beneath dentures or fixed prostheses. The socket-shield technique entails preparing a tooth root section simultaneous to immediate implant placement and has demonstrated histologic and clinical results contributory to esthetic implant treatment. A retrospective 10-patient case series treating 14 partial extraction sites demonstrates how a modification of the socket-shield technique can successfully develop pontic sites and preserve the ridge. PMID:27100812

  10. Abrasiveness of conventional and specific denture-cleansing dentifrices.

    PubMed

    Sorgini, Danilo Balero; Silva-Lovato, Claudia Helena da; de Souza, Raphael Freitas; Davi, Letícia Resende; Paranhos, Helena de Freitas Oliveira

    2012-01-01

    This study analyzed the weight loss and surface roughness caused in Plexiglass specimens by conventional dentifrices (Sorriso, Colgate and Close Up) and specific dentifrices used for cleaning of dentures (Corega and Dentu Creme). Plexiglass specimens were divided into 6 groups (n=6) including: a control (distilled water - DW) and experimental groups. Brushing was performed in a toothbrushing machine with a soft brush and a dentifrice suspension and DW according to different brushing times (50, 100, 200 and 250 min -18,000, 36,000, 72,000 and 90,000 cycles, respectively, calculated to correspond to 1, 2, 4 and 5 years of regular brushing). The results of weight loss and surface roughness were analyzed by ANOVA and Tukey's test at 5% significance level. In all tested times, the effect of DW was insignificant. Dentifrices differed significantly from DW in the initial period. Corega dentifrice caused greater mass loss in all studied times, followed by Close Up. Dentifrices resulted in a surface roughness similar to the DW at 50 min. In the other times, Sorriso, Colgate and Corega caused more surface roughness than DW. In conclusion, specific dentifrices caused larger mass loss and lower surface roughness as conventional dentifrice. PMID:22666774

  11. Influence of palatal surface shape of dentures on food perception.

    PubMed

    Tanaka, A; Kodaira, Y; Ishizaki, K; Sakurai, K

    2008-10-01

    The purpose of this study was to clarify the influence of the palatal surface shape of dentures on food perception. Eighteen healthy dentulous subjects (mean age, 24 years) were investigated. Four types of experimental plate were used: (i) a tailor-made plate, (ii) an average-model plate, (iii) a smooth plate, and (iv) a wrinkle plate. Test foods consisted of Bavarian cream cubes containing one to three mustard seeds and six raw carrot pieces of different shapes. Bavarian cream cubes with three seeds were used for analysis. Other foods were used as dummy foods. Subjects were required to wear experimental plates and press test foods placed on the anterior area of the tongue against the experimental plates. We measured time required to perceive number of spherical bodies, rate of correct answers, and level of perception with each type of experimental plate using a 100-mm visual analogue scale. The results showed a significant difference in response time between the average-model plate and the other experimental plates, with response time longest for the average-model plate. On the other hand, no significant differences in rate of correct answers regarding number of spherical bodies or level of perception were found among the experimental plates. When incisive papilla, palatine suture and palatal rugae based on the standard Japanese shape were replicated on the palatal surface of the plates, the time required for food perception during ingestion was prolonged in comparison to plates with other palatal surface shapes. PMID:18713309

  12. Structural analysis of bioceramic materials for denture application

    NASA Astrophysics Data System (ADS)

    Rauf, Nurlaela; Tahir, Dahlang; Arbiansyah, Muhammad

    2016-03-01

    Structural analysis has been performed on bioceramic materials for denture application by using X-ray diffraction (XRD), X-ray fluorescence (XRF), and Scanning Electron Microscopy (SEM). XRF is using for analysis chemical composition of raw materials. XRF shows the ratio 1 : 1 : 1 : 1 between feldspar, quartz, kaolin and eggshell, respectively, resulting composition CaO content of 56.78 %, which is similar with natural tooth. Sample preparation was carried out on temperature of 800 °C, 900 °C and 1000 °C. X-ray diffraction result showed that the structure is crystalline with trigonal crystal system for SiO2 (a=b=4.9134 Å and c=5.4051 Å) and CaH2O2 (a=b=3.5925 Å and c=4.9082 Å). Based on the Scherrer's equation showed the crystallite size of the highest peak (SiO2) increase with increasing the temperature preparation. The highest hardness value (87 kg/mm2) and match with the standards of dentin hardness. The surface structure was observed by using SEM also discussed.

  13. Measurement of Mucosal Thickness in Denture-bearing Area of Edentulous Mandible

    PubMed Central

    Dong, Jian; Zhang, Fei-Yu; Wu, Guang-Hui; Zhang, Wei; Yin, Jian

    2015-01-01

    Background: The thickness of the alveolar mucosa influences the probability of the occurrence of denture-induced irritations. Thick denture-supporting tissues offer relief from mucosal tenderness and ulcers; however, the uniformity of the thickness across the entire mandibular alveolar mucosa cannot be accurately determined in edentulous patients. This study aimed to assess the mucosal thickness of the denture-bearing area in the edentulous mandible. Methods: Twenty-seven edentulous patients underwent cone-beam computed tomography scanning, wherein the patients wore a record base to retract soft tissues away from the alveolar mucosa. The measured regions were the central incisor (IC), lateral incisor (IL), canine (Ca), first premolar (P1), second premolar (P2), first molar (M1), and second molar (M2) regions. The thickness was measured in the alveolar ridge crest (T), buccal (B1–B4), and lingual (L1–L4) alveolar ridge mucosa. The average thickness of the mucosa at buccal sides (B) and lingual sides (L) were also assessed. Results: The differences in the mucosal thickness between the left and right sides were not significant. In the Ca–M2 regions, T was the thickest, and L3 was the thinnest of all the measured points in the same regions. L was significantly less than B in posterior regions (P < 0.01). On the other hand, M2 at L4 was thinnest of all the measured regions from Ca to M2 (P < 0.01), and was thicker than IC, IL, P1, and P2 at B2. Conclusions: Since the mucosal thickness of denture-bearing area in the edentulous mandible is not uniform; the tissue surface of the denture base or custom tray should be selectively relieved, which may reduce the risk of denture-induced irritations. PMID:25635429

  14. Effect of Antimicrobial Denture Base Resin on Multi-Species Biofilm Formation.

    PubMed

    Zhang, Keke; Ren, Biao; Zhou, Xuedong; Xu, Hockin H K; Chen, Yu; Han, Qi; Li, Bolei; Weir, Michael D; Li, Mingyun; Feng, Mingye; Cheng, Lei

    2016-01-01

    Our aims of the research were to study the antimicrobial effect of dimethylaminododecyl methacrylate (DMADDM) modified denture base resin on multi-species biofilms and the biocompatibility of this modified dental material. Candida albicans (C. albicans), Streptococcus mutans (S. mutans), Streptococcus sanguinis (S. sanguinis), as well as Actinomyces naeslundii (A. naeslundii) were used for biofilm formation on denture base resin. Colony forming unit (CFU) counts, microbial viability staining, and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) array were used to evaluate the antimicrobial effect of DMADDM. C. albicans staining and Real-time PCR were used to analyze the morphology and expression of virulence genes of C. albicans in biofilm. Lactate dehydrogenase (LDH) array and Real-time PCR were conducted to examine the results after biofilm co-cultured with epithelial cell. Hematoxylin and eosin (HE) staining followed by histological evaluation were used to study the biocompatibility of this modified material. We found that DMADDM containing groups reduced both biomass and metabolic activity of the biofilm significantly. DMADDM can also inhibit the virulence of C. albicans by means of inhibiting the hyphal development and downregulation of two virulence related genes. DMADDM significantly reduced the cell damage caused by multi-species biofilm according to the LDH activity and reduced the expression of IL-18 gene of the cells simultaneously. The in vivo histological evaluation proved that the addition of DMADDM less than 6.6% in denture material did not increase the inflammatory response (p > 0.05). Therefore, we proposed that the novel denture base resin containing DMADDM may be considered as a new promising therapeutic system against problems caused by microbes on denture base such as denture stomatitis. PMID:27367683

  15. A comparative study on complete and implant retained denture treatments: a biomechanics perspective.

    PubMed

    Chen, Junning; Ahmad, Rohana; Suenaga, Hanako; Li, Wei; Swain, Michael; Li, Qing

    2015-02-01

    Although implant-retained overdenture allows edentulous patients to take higher occlusal forces than the conventional complete dentures, the biomechanical influences have not been explored yet. Clinically, there is limited knowledge and means for predicting localized bone remodelling after denture treatment with and without implant support. By using finite element (FE) analysis, this article provides an in-silico approach to exploring the treatment effects on the oral mucosa and potential resorption of residual ridge under three different denture configurations in a patient-specific manner. Based on cone beam computerized tomography (CBCT) scans, a 3D heterogeneous FE model was created; and the supportive tissue, mucosa, was characterized as a hyperelastic material. A measured occlusal load (63N) was applied onto three virtual models, namely complete denture, two and four implant-retained overdentures. Clinically, the bone resorption was measured after one year in the two implant-retained overdenture treatment. Despite the improved stability and enhanced masticatory function, the implant-retained overdentures demonstrated higher hydrostatic stress in mucosa (43.6kPa and 39.9kPa for two and four implants) at the posterior ends of the mandible due to the cantilever effect, than the complete denture (33.4kPa). Hydrostatic pressure in the mucosa signifies a critical indicator and can be correlated with clinically measured bone resorption, pointing to severer mandibular ridge resorption posteriorly with implant-retained overdentures. This study provides a biomechanical basis for denture treatment planning to improve long-term outcomes with minimal residual ridge resorption. PMID:25560272

  16. Effect of Cigarette Smoke on Surface Roughness of Different Denture Base Materials

    PubMed Central

    Mahross, Hamada Zaki; Mohamed, Mahmoud Darwish; Hassan, Ahmed Mohammed

    2015-01-01

    Background Surface roughness is an important property of denture bases since denture bases are in contact with oral tissues and a rough surface may affect tissues health due to microorganism accumulation. Therefore, the effect of cigarette smoke on the surface roughness of two commercially available denture base materials was evaluated to emphasize which type has superior properties for clinical use. Materials and Methods A total numbers of 40 specimens were constructed from two commercially available denture base materials; heat-cured PMMA and visible light cured UDMA resins (20 for each). The specimens for each type were randomly divided into: Group I: Heat cured resin control group; Group II: Heat cured acrylic resin specimens exposed to cigarette smoking; Group III: Light cured resin control group; Group IV: Light cured resin specimens exposed to cigarette smoking. The control groups used for immersion in distilled water and the smoke test groups used for exposure to cigarette smoking. The smoke test groups specimens were exposed to smoking in a custom made smoking chamber by using 20 cigarettes for each specimen. The surface roughness was measured by using Pocket SurfPS1 profilometer and the measurements considered as the difference between the initial and final roughness measured before and after smoking. Results The t-test for paired observation of test specimens after exposure to smoking was indicated significant change in surface roughness for Group II (p< 0.05) but has no significance with Group IV. Otherwise, there were no significant differences with control groups (Group I and III). Conclusion The surface roughness of the dentures constructed from heat cured acrylic resin had been increased after exposure to cigarette smoke but had no impact on the dentures constructed from visible light cured resin. PMID:26501010

  17. Effect of Antimicrobial Denture Base Resin on Multi-Species Biofilm Formation

    PubMed Central

    Zhang, Keke; Ren, Biao; Zhou, Xuedong; Xu, Hockin H. K.; Chen, Yu; Han, Qi; Li, Bolei; Weir, Michael D.; Li, Mingyun; Feng, Mingye; Cheng, Lei

    2016-01-01

    Our aims of the research were to study the antimicrobial effect of dimethylaminododecyl methacrylate (DMADDM) modified denture base resin on multi-species biofilms and the biocompatibility of this modified dental material. Candida albicans (C. albicans), Streptococcus mutans (S. mutans), Streptococcus sanguinis (S. sanguinis), as well as Actinomyces naeslundii (A. naeslundii) were used for biofilm formation on denture base resin. Colony forming unit (CFU) counts, microbial viability staining, and 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) array were used to evaluate the antimicrobial effect of DMADDM. C. albicans staining and Real-time PCR were used to analyze the morphology and expression of virulence genes of C. albicans in biofilm. Lactate dehydrogenase (LDH) array and Real-time PCR were conducted to examine the results after biofilm co-cultured with epithelial cell. Hematoxylin and eosin (HE) staining followed by histological evaluation were used to study the biocompatibility of this modified material. We found that DMADDM containing groups reduced both biomass and metabolic activity of the biofilm significantly. DMADDM can also inhibit the virulence of C. albicans by means of inhibiting the hyphal development and downregulation of two virulence related genes. DMADDM significantly reduced the cell damage caused by multi-species biofilm according to the LDH activity and reduced the expression of IL-18 gene of the cells simultaneously. The in vivo histological evaluation proved that the addition of DMADDM less than 6.6% in denture material did not increase the inflammatory response (p > 0.05). Therefore, we proposed that the novel denture base resin containing DMADDM may be considered as a new promising therapeutic system against problems caused by microbes on denture base such as denture stomatitis. PMID:27367683

  18. Peel strength of denture liner to PMMA and polyamide: laser versus air-abrasion

    PubMed Central

    Bagis, Bora; Özcan, Mutlu; Durkan, Rukiye; Turgut, Sedanur; Ates, Sabit Melih

    2013-01-01

    PURPOSE This study investigated the effect of laser parameters and air-abrasion on the peel strength of silicon-based soft denture liner to different denture resins. MATERIALS AND METHODS Specimens (N=180) were prepared out of three different denture base resins (Rodex, cross-linked denture base acrylic resin; Paladent, heat-cured acrylic resin; Deflex, Polyamide resin) (75 mm × 25 mm × 3 mm). A silicon-based soft denture liner (Molloplast B) was applied to the denture resins after the following conditioning methods: a) Air-abrasion (50 µm), b) Er,Cr:YSGG laser (Waterlase MD Turbo, Biolase Technology) at 2 W-20 Hz, c) Er,Cr:YSGG laser at 2 W-30 Hz, d) Er,Cr:YSGG laser at 3 W-20 Hz, e) Er,Cr:YSGG laser at 3 W-30 Hz. Non-conditioned group acted as the control group. Peel test was performed in a universal testing machine. Failure modes were evaluated visually. Data were analyzed using two-way ANOVA and Tukey's test (α=.05). RESULTS Denture liner tested showed increased peel strength after laser treatment with different parameters (3.9±0.4 - 5.58±0.6 MPa) compared to the control (3.64±0.5 - 4.58±0.5 MPa) and air-abraded groups (3.1±0.6 - 4.46±0.3 MPa), but the results were not statistically significant except for Paladent, with the pretreatment of Er,Cr:YSGG laser at 3 W-20 Hz. Polyamide resin after air-abrasion showed significantly lower peel strength than those of other groups (3.1±0.6 MPa). CONCLUSION Heat-cured acrylic resin, PMMA, may benefit from Er,Cr:YSGG laser treatment at 3 W-20 Hz irradiation. Air-abrasion of polyamide resins should be avoided not to impair their peel bond strengths to silicon-based soft denture liners. PMID:24049570

  19. Biometric Denture Space- Concept of Neutral Zone Revisited Using A Hydrocolloid Impression Material

    PubMed Central

    Umamaheswaran, Aruna; Nayar, Sanjna

    2015-01-01

    Though the concept of neutral zone in making complete denture and its significance are well known, the material of choice has always been experimented to achieve better results. Recording of neutral zone using irreversible hydrocolloid (Alginate) as a material of choice would make the way of recording the neutral zone easier, as well as comfortable for the patient, when compared with other materials used for the purpose. This article describes the method of recording the biometric denture space (neutral zone) using hydrocolloid impression material which is most commonly used in everyday dental practice. PMID:26673250

  20. CAD/CAM complete dentures: a review of two commercial fabrication systems.

    PubMed

    Kattadiyil, Mathew T; Goodacre, Charles J; Baba, Nadim Z

    2013-06-01

    The use of computer-aided design and computer-aided manufacturing (CAD/CAM) has become available for complete dentures through the AvaDent and Dentca systems. AvaDent uses laser scanning and computer technology. Teeth are arranged and bases formed using proprietary software.The bases are milled from prepolymerized pucks of resin. Dentca uses computer software to produce virtual maxillary and mandibular edentulous ridges, arrange the teeth and form bases. The dentures are fabricated using a conventional processing technique. PMID:23875432

  1. Clinical strategies for complete denture rehabilitation in a patient with Parkinson disease and reduced neuromuscular control.

    PubMed

    Haralur, Satheesh B

    2015-01-01

    The dentist has a large role in geriatric health care for the ever increasing elder population with associated physical and neurological disorders. The Parkinson disease is progressive neurological disorder with resting tremor, bradykinesia, akinesia, and postural instability. The psychological components of disease include depression, anxiety, and cognitive deficiency. Poor oral hygiene, increased susceptibility for dental caries, and periodontal diseases predispose them to early edentulism. The number of Parkinson affected patients visiting dental clinic seeking complete denture is growing. This case report explains the steps involved in the complete denture rehabilitation of Parkinson patient. The effective prosthesis will help in alleviating functional, aesthetic, and psychological disabilities of the patient. PMID:25737785

  2. Colour stability of denture teeth submitted to different cleaning protocols and accelerated artificial aging.

    PubMed

    Freire, T S; Aguilar, F G; Garcia, L da Fonseca Roberti; Pires-de-Souza, F de Carvalho Panzeri

    2014-03-01

    Acrylic resin is widely used for artificial teeth manufacturing due to several important characteristics; however, this material do not present acceptable colour stability over the course of time. This study evaluated the effect of different cleaning protocols and accelerated artificial aging on colour stability of denture teeth made of acrylic resin. Sixty denture teeth in dark and light shades were used, and separated according to the treatment to which they were submitted. Results demonstrated that colour stability of artificial teeth is influenced by the cleaning solution and artificial aging, being dark teeth more susceptible to colour alteration than lighter ones. PMID:24922996

  3. Antifungal activity, biofilm-controlling effect, and biocompatibility of poly(N-vinyl-2-pyrrolidinone)-grafted denture materials

    PubMed Central

    Sun, Xinbo; Cao, Zhengbing; Yeh, Chih-Ko; Sun, Yuyu

    2013-01-01

    Colonization and biofilm-formation of Candida species on denture surfaces cause Candida-associated denture stomatitis (CADS), a common, recurring disease affecting up to 67% of denture wearers. We developed poly(N-vinyl-2-pyrrolidinone)-grafted denture materials that can be repeatedly recharged with various antifungal drugs to achieve long-term antifungal and biofilm-controlling effects. The monomer, N-vinyl-2-pyrrolidinone (NVP), was grafted onto poly(methyl methacrylate) denture resins through plasma-initiated grafting polymerization. The physical properties and biocompatibility of the resulting resins were not negatively affected by the presence of up to 7.92% of grafted poly (N-vinyl-2-pyrrolidinone) (PNVP). Miconazole and chlorhexidine digluconate (CD) were used as model antifungal drugs. PNVP grafting significantly increased the drug absorption capability of the resulting denture materials. Further, the new materials showed sustained drug release and provided antifungal effects for weeks (in the case of CD) to months (in the case of miconazole). The drug-depleted resins could be recharged with the same or a different class of antifungal drug to further extend antifungal duration. If needed, drugs on the PNVP-grafted denture materials could be “washed out” (quenched) by treating with PNVP aqueous solutions to stop drug release. These results point to great potentials of the new materials in controlling biofilm-formation in a wide range of device-related applications. PMID:23708753

  4. The effect of denture installation at mandibular rest position on unsteady motion of the centre of pressure in postural sway.

    PubMed

    Yoshino, N; Nozaki, K; Maeda, Y

    2016-07-01

    Wearing dentures has been believed to decrease the instability of the postural sway using the total length of centre of pressure (CoP) trajectory or the magnitude of its variability. However, the physical aspects of the postural sway have not been taken into account while evaluating the CoP in patients who wear dentures. The CoP fluctuations are found to show a random walk process. Therefore, changes in the random movement of CoP caused by wearing dentures should be examined by nonlinear dynamics that enables analysis of the characteristics found in the random movement. We evaluated the effect of complete denture installation on CoP sway for twenty-six edentulous patients by performing the following steps. First, we excluded subjects who did not show crossover in spectral analyses. Then, we evaluated the spectral characteristics and phase shifts of the velocities of CoP sway for the subjects who showed crossover. We found that wearing complete dentures decreased the fluctuations in the high-frequency part of the power spectral density (PSD) and the phase shift in the mediolateral direction. On the other hand, we also found that the use of complete dentures decreased the fluctuations of PSD amplitude in the anteroposterior direction. From the point of view of the kinetic energy of the musculoskeletal system, we suggested that the use of complete dentures could reduce the energy consumption for the standing posture. PMID:27084494

  5. Power spectrum density analysis for the influence of complete denture on the brain function of edentulous patients - pilot study

    PubMed Central

    Perumal, Praveen; Anitha, Kuttae Viswanathan; Reddy, Jetti Ramesh; Muthukumar, Balasubramanium

    2016-01-01

    PURPOSE This pilot study was to find the influence of complete denture on the brain activity and cognitive function of edentulous patients measured through Electroencephalogram (EEG) signals. MATERIALS AND METHODS The study recruited 20 patients aged from 50 to 60 years requiring complete dentures with inclusion and exclusion criteria. The brain function and cognitive function were analyzed with a mental state questionnaire and a 15-minute analysis of power spectral density of EEG alpha waves. The analysis included edentulous phase and post denture insertion adaptive phase, each done before and after chewing. The results obtained were statistically evaluated. RESULTS Power Spectral Density (PSD) values increased from edentulous phase to post denture insertion adaption phase. The data were grouped as edentulous phase before chewing (EEG p1-0.0064), edentulous phase after chewing (EEG p2-0.0073), post denture insertion adaptive phase before chewing (EEG p3-0.0077), and post denture insertion adaptive phase after chewing (EEG p4-0.0096). The acquired values were statistically analyzed using paired t-test, which showed statistically significant results (P<.05). CONCLUSION This pilot study showed functional improvement in brain function of edentulous patients with complete dentures rehabilitation. PMID:27350852

  6. Stress analysis of a complete maxillary denture under various drop impact conditions: a 3D finite element study.

    PubMed

    Sunbuloglu, Emin

    2015-01-01

    Complete maxillary dentures are one of the most economic and easy ways of treatment for edentulous patients and are still widely used. However, their survival rate is slightly above three years. It is presumed that the failure reasons are not only due to normal fatigue but also emerge from damage based on unavoidable improper usage. Failure types other than long-term fatigue, such as over-deforming, also influence the effective life span of dentures. A hypothesis is presumed, stating that the premature/unexpected failures may be initiated by impact on dentures, which can be related to dropping them on the ground or other effects such as biting crispy food. Thus, the behavior of a complete maxillary denture under impact loading due to drop on a rigid surface was investigated using the finite element method utilizing explicit time integration and a rate-sensitive elastoplastic material model of polymethylmethacrylate (PMMA). Local permanent deformations have been observed along with an emphasis on frenulum region of the denture, regardless of the point of impact. Contact stresses at the tooth-denture base were also investigated. The spread of energy within the structure via wave propagation is seen to play a critical role in this fact. Stress-wave propagation is also seen to be an important factor that decreases the denture's fatigue life. PMID:24945936

  7. Physical Properties of Polyamide-12 versus PMMA Denture Base Material

    PubMed Central

    Wieckiewicz, Mieszko; Richter, Gert; Boening, Klaus W.

    2014-01-01

    Objectives. Polyamide-12 (PA) is a flexible material suited for denture bases and clasping. This study investigated its potential aging effects with a focus on surface roughness, color stability, and elasticity. Methods. PA specimens (Valplast) of 40 × 10 × 2 mm and equally measuring PMMA specimens (Palapress) as control were fabricated. Color changes after storage in air, water, coffee, and red wine (n = 10) were measured using the CIE L*a*b* color specification. Elasticity after thermocycling (1000, 3000, and 7000 cycles,  n = 15) was measured by three-point bending testing. Mean surface roughness (Ra) was determined after storage in the liquids mentioned above and thermocycling (n = 10). Results. Tukey's HSD test (P < 0.05) revealed statistically significant color changes of PA in red wine (ΔE = 4.27 after 12 days, ΔE = 6.90 after 12 days) and coffee (ΔE = 3.93 after 36 days) but no color changes in PMMA. Elastic modulus of PA was 845 MPa and not affected by thermocycling (Tukey's HSD test,  P > 0.81). Dry specimens showed significantly decreased elasticity (P < 0.001). Mean surface roughness (PA 0.20 μm, PMMA 0.28 μm) did not change significantly after thermocycling or storage (Mann-Whitney U-test,  0.16 < P < 0.65). Significance. PA exhibited a higher susceptibility to discoloration than PMMA. Neither surface roughness nor elasticity of PA was altered by artificial aging. PMID:24734225

  8. Marginal fit of anterior 3-unit fixed partial zirconia restorations using different CAD/CAM systems

    PubMed Central

    Song, Tae-Jin; Kwon, Taek-Ka; Han, Jung-Suk; Lee, Jai-Bong; Kim, Sung-Hun

    2013-01-01

    PURPOSE Few studies have investigated the marginal accuracy of 3-unit zirconia fixed partial dentures (FPDs) fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM) system. The purpose of this study was to compare the marginal fit of zirconia FPDs made using two CAD/CAM systems with that of metal-ceramic FPDs. MATERIALS AND METHODS Artificial resin maxillary central and lateral incisors were prepared for 3-unit FPDs and fixed in yellow stone. This model was duplicated to epoxy resin die. On the resin die, 15 three-unit FPDs were fabricated per group (45 in total): Group A, zirconia 3-unit FPDs made with the Everest system; Group B, zirconia 3-unit FPDs made with the Lava system; and Group C, metal-ceramic 3-unit FPDs. They were cemented to resin dies with resin cement. After removal of pontic, each retainer was separated and observed under a microscope (Presize 440C). Marginal gaps of experimental groups were analyzed using one-way ANOVA and Duncan test. RESULTS Mean marginal gaps of 3-unit FPDs were 60.46 µm for the Everest group, 78.71 µm for the Lava group, and 81.32 µm for the metal-ceramic group. The Everest group demonstrated significantly smaller marginal gap than the Lava and the metal-ceramic groups (P<.05). The marginal gap did not significantly differ between the Lava and the metal-ceramic groups (P>.05). CONCLUSION The marginal gaps of anterior 3-unit zirconia FPD differed according to CAD/CAM systems, but still fell within clinically acceptable ranges compared with conventional metal-ceramic restoration. PMID:24049561

  9. 42 CFR 440.120 - Prescribed drugs, dentures, prosthetic devices, and eyeglasses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 4 2011-10-01 2011-10-01 false Prescribed drugs, dentures, prosthetic devices, and eyeglasses. 440.120 Section 440.120 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL ASSISTANCE PROGRAMS SERVICES: GENERAL PROVISIONS Definitions § 440.120 Prescribed drugs,...

  10. Incorporation of Radio Frequency Identification Tag in Dentures to Facilitate Recognition and Forensic Human Identification

    PubMed Central

    Nuzzolese, E; Marcario, V; Di Vella, G

    2010-01-01

    Forensic identification using odontology is based on the comparison of ante-mortem and post mortem dental records. The insertion of a radio frequency identification (RFId) tag into dentures could be used as an aid to identify decomposed bodies, by storing personal identification data in a small transponder that can be radio-transmitted to a reader connected to a computer. A small passive, 12 x 2,1 mm, read-only RFId-tag was incorporated into the manufacture of three trial complete upper dentures and tested for a signal. The aim of this article is to demonstrate the feasibility of manufacturing such a dental prosthesis, the technical protocols for its implantation in the denture resin and its working principles. Future research and tests are required in order to verify human compatibility of the tagged denture and also to evaluate any potential deterioration in strength when subjected to high temperatures, or for damage resulting from everyday wear and tear. It should also be able to withstand the extreme conditions resulting from major accidents or mass disasters and procedures used to perform a forensic identification. PMID:20657641

  11. Long-term clinical evaluation of fixed dentures--two to fifteen years after insertion.

    PubMed

    Hubálková, H; Charvát, J; Dostálová, T; Linetskiy, I

    2005-01-01

    Fixed denture durability is characterized as a period of time for which a dental appliance satisfies functional and esthetic requirements. First of all, its durability is based on the properties of materials it is made of, and depends, at the same time, on the characteristics of biological environment, in which the denture is placed. The purpose of this study was a long-term monitoring of changes taking place in the fixed dental constructions during their application in the oral cavity. These changes were to be evaluated for different types of materials used for fixed dentures manufacturing, namely metal alloys, ceramics, and plastics. A set of 454 full crowns from 134 patients divided in 6 clinical studies was examined and both qualitative and quantitative changes evaluated after 2 and 8 to 15 years after cementation. Clinical assessment adopted the United States Public Health Service System criteria. Alloys of precious metals veneered with ceramics are considered the optimal method of choice for both high precision of execution and consideration of future changes brought on by the use of the dentures. PMID:16007909

  12. Nitric Oxide Concentration and Other Salivary Changes after Insertion of New Complete Dentures in Edentulous Subjects.

    PubMed

    Breseghelo, Maria de Lourdes; Guillo, Lídia Andreu; Nogueira, Túlio Eduardo; Leles, Cláudio Rodrigues

    2016-01-01

    Objective. To assess changes in levels of salivary nitric oxide (NO) after insertion of new complete dentures and its association with clinical and salivary parameters. Methods. Nineteen fully edentulous subjects were included, mean age 64.4. Unstimulated whole saliva was collected before and after insertion of the dentures, at follow-up visits, and after 12 months. The concentration of the final stable NO product (nitrite) was measured by a colorimetric assay based on the Griess reaction. Clinical parameters were assessed during all clinical visits. Results. Functional adaptation to the dentures progressively improved, with no complaints at the long-term follow-up. NO concentration was not influenced by the level of functional adaptation, presence of injuries to the mucosa, salivary flow, and saliva viscosity. Pairwise comparison showed a reduction in NO concentration at the first follow-up compared to baseline values but differences were not statistically significant. Significant differences were observed in NO concentrations at the long-term follow-up when compared to the first (p = 0.024) and second (p = 0.027) visits. Conclusion. NO concentration reduced after denture insertion and returned to baseline levels in the long-term follow-up. This appears to be an autonomic response of the body and provides valuable complementary information for the management of the edentulous patient. PMID:27034674

  13. Clinicopathologic correlation: palatal mass interfering with seating of a maxillary denture.

    PubMed

    Farrkh, Amana; Closmann, James J; Parashar, Pallavi; Borris, Thomas J

    2015-01-01

    This paper is a clinicopathologic correlation regarding a 61-year-old patient with an ill-fitting maxillary denture. Examination revealed a firm, nontender palatal mass. Descriptions of the clinical findings, work-up, differential diagnosis, histological observations, and diagnosis of the lesion are presented. PMID:26147173

  14. Cross-contamination in the dental laboratory through the polishing procedure of complete dentures.

    PubMed

    Agostinho, Alessandra Marçal; Miyoshi, Paula Regina; Gnoatto, Nelson; Paranhos, Helena de Freitas Oliveira; Figueiredo, Luciene Cristina de; Salvador, Sérgio Luiz

    2004-01-01

    Polishing of dental prostheses can cause a dangerous cycle of cross-contamination involving dentists, laboratory technicians, patients and auxiliary personnel. The aim of this study was to show the microbial contamination in the dental laboratory during the polishing procedure of complete dentures. For this purpose, 4 experiments were conducted. Experiment I -- Determination of the total colony-forming units (CFU) counts contaminating complete maxillary dentures. During the polishing procedure, determination of the CFU counts transferred to the operator (Experiment II) and of the total CFU counts transferred to previously sterilized complete dentures (Experiment III). Experiment IV -- The total counts of remaining CFU in the lathe spindle after Experiments II and III. Complete dentures were highly contaminated (mean = 1.4 x 10(7) CFU/mL). There was a elevated level of contamination by splatter and aerosols. There was high microbial transfer from the contaminated lathe spindle to the sterile prostheses (mean = 1.7 x 10(7) CFU/mL). The spindles were highly contaminated after polishing procedures (mean = 3.5 x 10(8) CFU/mL). The polishing of dental prostheses is a possible source of transmission of communicable diseases in the laboratory and requires improved techniques for infection control. PMID:15776197

  15. Influence of inner circular sealing area impression method on the retention of complete dentures.

    PubMed

    Wang, Cun-Wei; Shao, Qi; Sun, Hui-Qiang; Mao, Meng-Yun; Zhang, Xin-Wei; Gong, Qi; Xiao, Guo-Ning

    2015-01-01

    The aims of the present study were to describe an impression method of "inner circular sealing area" and to evaluate the effect of the method on retention, aesthetics and comfort of complete dentures, which lack labial base for patients with maxillary protrusions. Three patients were subjected to the experiment, and two sets of complete maxillary dentures were made for each patient; the first set was made without labial base via an inner circular sealing area method (experimental group) and the second had an intact base that was made with conventional methods (control group). Retention force tests were implemented with a tensile strength assessment device to assess the retention and a visual analogue scale (VAS) was used to evaluate the comfort between the two groups. Results showed larger retention force, better aesthetics and more comfort in the experimental group. The improved two-step impression method formed an inner circular sealing area that prevented damage to the peripheral border seal effect of the denture caused by incomplete bases and obtained better denture retention. PMID:25831114

  16. Nitric Oxide Concentration and Other Salivary Changes after Insertion of New Complete Dentures in Edentulous Subjects

    PubMed Central

    Breseghelo, Maria de Lourdes; Guillo, Lídia Andreu; Nogueira, Túlio Eduardo

    2016-01-01

    Objective. To assess changes in levels of salivary nitric oxide (NO) after insertion of new complete dentures and its association with clinical and salivary parameters. Methods. Nineteen fully edentulous subjects were included, mean age 64.4. Unstimulated whole saliva was collected before and after insertion of the dentures, at follow-up visits, and after 12 months. The concentration of the final stable NO product (nitrite) was measured by a colorimetric assay based on the Griess reaction. Clinical parameters were assessed during all clinical visits. Results. Functional adaptation to the dentures progressively improved, with no complaints at the long-term follow-up. NO concentration was not influenced by the level of functional adaptation, presence of injuries to the mucosa, salivary flow, and saliva viscosity. Pairwise comparison showed a reduction in NO concentration at the first follow-up compared to baseline values but differences were not statistically significant. Significant differences were observed in NO concentrations at the long-term follow-up when compared to the first (p = 0.024) and second (p = 0.027) visits. Conclusion. NO concentration reduced after denture insertion and returned to baseline levels in the long-term follow-up. This appears to be an autonomic response of the body and provides valuable complementary information for the management of the edentulous patient. PMID:27034674

  17. Physical property comparison of 11 soft denture lining materials as a function of accelerated aging.

    PubMed

    Dootz, E R; Koran, A; Craig, R G

    1993-01-01

    Soft denture-lining materials are an important treatment option for patients who have chronic soreness associated with dental prostheses. Three distinctly different types of materials are generally used. These are plasticized polymers or copolymers, silicones, or polyphosphazene fluoroelastomer. The acceptance of these materials by patients and dentists is variable. The objective of this study is to compare the tensile strength, percent elongation, hardness, tear strength, and tear energy of eight plasticized polymers or copolymers, two silicones, and one polyphosphazene fluoroelastomer. Tests were run at 24 hours after specimen preparation and repeated after 900 hours of accelerated aging in a Weather-Ometer device. The data indicated a wide range of physical properties for soft denture-lining materials and showed that accelerated aging dramatically affected the physical and mechanical properties of many of the elastomers. No soft denture liner proved to be superior to all others. The data obtained should provide clinicians with useful information for selecting soft denture lining materials for patients. PMID:8455156

  18. Dynamic viscoelastic properties of processed soft denture liners: Part II--Effect of aging.

    PubMed

    Wagner, W C; Kawano, F; Dootz, E R; Koran, A

    1995-09-01

    The proper functioning of soft denture liners depends to a great extent on their mechanical properties. As with many polymers these materials are affected by aging. Twelve soft denture liners were processed by a laboratory according to the manufacturers' directions. Five specimens of each material were tested without aging. Five additional specimens of each material were subjected to 900 hours of accelerated aging in a Weather-Ometer instrument. These were tested with a dynamic viscoelastometer at three frequencies and two temperatures, and data for 37 degrees C and 1 Hz was obtained. Two of the ethyl methacrylate resins demonstrated the largest increases in storage (E') and loss moduli (E") after aging. These materials also showed the greatest overall E' and E". One denture liner material exhibited 673% and 488% increases in E' and E", and other materials showed smaller increases. The effects of aging on the damping factor (tan delta) were varied and five materials showed increased tan delta. Only two ethyl methacrylate resins developed lower tan delta. All the silicone and polyphosphazine rubbers showed small changes after aging and had the lowest tan delta values. Significance of differences between materials and treatments was tested with ANOVA, Scheffé intervals, and t-tests at a = 0.05. The ethyl methacrylate soft denture liners were affected the most by accelerated aging, and the silicones and polyphosphazine were least affected. The ethyl methacrylate resins also had the greatest values of E', E", and tan delta after aging. PMID:7473285

  19. Prediction of facial deformation after complete denture prosthesis using BP neural network.

    PubMed

    Cheng, Cheng; Cheng, Xiaosheng; Dai, Ning; Jiang, Xiaotong; Sun, Yuchun; Li, Weiwei

    2015-11-01

    With the accelerated aging of world population, complete denture prosthesis plays an increasingly important role in mouth rehabilitation. In addition to recovering stomatognathic system function, restoring the appearance of a third of the area under the face has become a great challenge in complete denture prosthesis. This study analyzes the interactive relationship between the appearance of a third of the area under the face and complete denture, and proposes a new method to predict facial deformation after complete denture prosthesis. Firstly, to improve computational efficiency, the feature template is constructed to replace the deformed facial region. Secondly, a forecast model of elastic deformation is constructed using BP neural network and predicts elastic deformation amount because of the inhomogeneous, anisotropic and nonlinear material properties of soft tissue. Finally, a new feature template is calculated using deformation amount, and the deformation of preoperative model is simulated using Laplacian deformation technique. The average error rates of different hidden layer nodes in the neural network are analysed. Deformation and postoperative models are superimposed for match analysis. Experimental results show that this method can predict facial soft tissue deformation quickly and accurately. PMID:26386549

  20. Adenoid removal

    MedlinePlus

    ... This does not cause problems most of the time. Alternative Names Adenoidectomy; Removal of adenoid glands Images Adenoid removal - series References Wetmore RF. Tonsils and adenoids. In: Kliegman ...

  1. Factors affecting the bond strength of denture base and reline acrylic resins to base metal materials

    PubMed Central

    TANOUE, Naomi; MATSUDA, Yasuhiro; YANAGIDA, Hiroaki; MATSUMURA, Hideo; SAWASE, Takashi

    2013-01-01

    Objective The shear bond strengths of two hard chairside reline resin materials and an auto-polymerizing denture base resin material to cast Ti and a Co-Cr alloy treated using four conditioning methods were investigated. Material and Methods Disk specimens (diameter 10 mm and thickness 2.5 mm) were cast from pure Ti and Co-Cr alloy. The specimens were wet-ground to a final surface finish of 600 grit, air-dried, and treated with the following bonding systems: 1) air-abraded with 50-70-µm grain alumina (CON); 2) 1) + conditioned with a primer, including an acidic phosphonoacetate monomer (MHPA); 3) 1) + conditioned with a primer including a diphosphate monomer (MDP); 4) treated with a tribochemical system. Three resin materials were applied to each metal specimen. Shear bond strengths were determined before and after 10,000 thermocycles. Results The strengths decreased after thermocycling for all combinations. Among the resin materials assessed, the denture base material showed significantly (p<0.05) greater shear bond strengths than the two reline materials, except for the CON condition. After 10,000 thermocycles, the bond strengths of two reline materials decreased to less than 10 MPa for both metals. The bond strengths of the denture base material with MDP were sufficient: 34.56 MPa for cast Ti and 38.30 for Co-Cr alloy. Conclusion Bonding of reline resin materials to metals assessed was clinically insufficient, regardless of metal type, surface treatment, and resin composition. For the relining of metal denture frameworks, a denture base material should be used. PMID:24037070

  2. Application of electrolyzed acid water to sterilization of denture base part 1. Examination of sterilization effects on resin plate.

    PubMed

    Nagamatsu, Y; Tajima, K; Kakigawa, H; Kozono, Y

    2001-06-01

    Bactericidal activities of electrolyzed strong and weak acid waters for acrylic denture base resin were evaluated in order to discuss the applicability of these waters for sterilization of denture base. Only 1-minute immersion in the electrolyzed strong or weak acid water could completely eliminate the attached bacteria, Staphylococcus aureus 209P, on the resin plate. When the resin was relined with tissue conditioner, 5-minute immersion or 1- to 2-minute ultrasonic cleaning reduced the number of the bacteria from 10(5)/cm2 level to 10(1)/cm2 and no surviving bacteria could be detected after 10-minute treatment. These findings suggest that both the electrolyzed strong and weak acid waters are well applicable to the disinfectant for acrylic denture base showing excellent bactericidal activities in a significantly shorter treatment as compared with the conventional denture cleaning. PMID:11523978

  3. Antifungal Effect of Henna against Candida albicans Adhered to Acrylic Resin as a Possible Method for Prevention of Denture Stomatitis.

    PubMed

    Nawasrah, Amal; AlNimr, Amani; Ali, Aiman A

    2016-01-01

    Denture stomatitis is a very common disease affecting the oral mucosa of denture wearers. The aim of this study was to measure the antifungal effect of henna against Candida albicans adhered to acrylic resin as a possible method for prevention of denture stomatitis. One-hundred-eighty acrylic plates were prepared of heat-cured acrylic denture resin. The specimens were divided into six groups of 30 samples each. The first group was only polymer and monomer following the conventional manufacturer instruction for processing complete dentures. The other five groups were processed by adding different concentration of Yamani henna powder (Harazi) to the polymer in a concentration of henna: polymer 1%, 2.5%, 5%, 7.5% and 10%, respectively. Samples were incubated in artificial saliva rich with Candida albicans at 37 °C, and the effect of henna on Candida albicans was evaluated in two different methods: semi-quantitative slide count and a culture-based quantitative assay (quantitative). Variation in the number of live Candida was observed with the increase in the concentration of Yamani henna powder. It was observed that the variation in live Candida, between control group and group B (concentration of Yamani henna powder was 1%), was statistically significant with a p-value of 0.0001. Similarly, variations in live Candida were significant, when the concentration of powder was 7.5% or 10% in contrast with control group and p-values were 0.0001 and 0.001 respectively. Adding henna to acrylic resin denture could be effective in controlling Candida albicans proliferation on the denture surface; however, its effects on the physical properties of acrylic resin denture need further studies. PMID:27223294

  4. Influence of Surface Modifications of Acrylic Resin Teeth on Shear Bond Strength with Denture Base Resin-An Invitro Study

    PubMed Central

    Krishnan, Madhusudan; Krishnan, Chitra Shankar; Azhagarasan, N.S.; Sampathkumar, Jayakrishnakumar; Ramasubramanian, Hariharan

    2015-01-01

    Background Debonding of artificial teeth from the denture base is an important issue for edentulous patients rehabilitated with conventional or implant supported complete dentures. Aim The purpose of this study was to evaluate shear bond strength between denture base resin and acrylic resin denture teeth subjected to three different surface modifications on the ridge lap area as compared to unmodified denture teeth. Materials and Methods Forty acrylic resin central incisor denture teeth were selected and randomly divided into four test groups. The teeth in each group were subjected to one of the three different surface modifications, namely, chemical treatment, sandblasting and placement of retentive grooves on the ridge lap area respectively, prior to packing of the denture base resin. The group with unmodified teeth served as control. Forty acrylic resin test blocks thus obtained were tested for shear bond strength between acrylic resin teeth and denture base resin in Universal Testing Machine. Data obtained was statistically analysed using one-way ANOVA and Student- Newman- Keul’s test (p< 0.05). Results Analysis of shear bond strength revealed that retentive grooves on the ridge lap area showed highest bond strength values followed by sandblasting and both were statistically significant compared to the control and chemically treated groups. Unmodified surface of the resin teeth showed the least bond strength. Conclusion Within the limitations of this invitro study the placement of retentive grooves or sandblasting of the ridge lap area showed highly significant improvement in shear bond strength compared to the unmodified surface. Chemical treatment did not result in any significant improvement in the shear bond strength compared to the unmodified surface. PMID:26501005

  5. Antifungal Effect of Henna against Candida albicans Adhered to Acrylic Resin as a Possible Method for Prevention of Denture Stomatitis

    PubMed Central

    Nawasrah, Amal; AlNimr, Amani; Ali, Aiman A.

    2016-01-01

    Denture stomatitis is a very common disease affecting the oral mucosa of denture wearers. The aim of this study was to measure the antifungal effect of henna against Candida albicans adhered to acrylic resin as a possible method for prevention of denture stomatitis. One-hundred-eighty acrylic plates were prepared of heat-cured acrylic denture resin. The specimens were divided into six groups of 30 samples each. The first group was only polymer and monomer following the conventional manufacturer instruction for processing complete dentures. The other five groups were processed by adding different concentration of Yamani henna powder (Harazi) to the polymer in a concentration of henna: polymer 1%, 2.5%, 5%, 7.5% and 10%, respectively. Samples were incubated in artificial saliva rich with Candida albicans at 37 °C, and the effect of henna on Candida albicans was evaluated in two different methods: semi-quantitative slide count and a culture-based quantitative assay (quantitative). Variation in the number of live Candida was observed with the increase in the concentration of Yamani henna powder. It was observed that the variation in live Candida, between control group and group B (concentration of Yamani henna powder was 1%), was statistically significant with a p-value of 0.0001. Similarly, variations in live Candida were significant, when the concentration of powder was 7.5% or 10% in contrast with control group and p-values were 0.0001 and 0.001 respectively. Adding henna to acrylic resin denture could be effective in controlling Candida albicans proliferation on the denture surface; however, its effects on the physical properties of acrylic resin denture need further studies. PMID:27223294

  6. Influence of Prosthetic Screw Material on Joint Stability in Passive and Non-Passive Implant-Supported Dentures

    PubMed Central

    Spazzin, Aloísio Oro; Henriques, Guilherme Elias Pessanha; de Arruda Nóbilo, Mauro Antônio; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Mesquita, Marcelo Ferraz

    2009-01-01

    Objectives: This study evaluated the influence of prosthetic screw material on joint stability in implantsupported dentures at two levels of fit. Methods: Ten mandibular implant-supported dentures were fabricated. Twenty cast models were fabricated using these dentures. Four groups (n=10) were tested, according to the vertical fit of the dentures [passive and non-passive] and prosthetic screw materials [titanium (Ti) or gold (Au) alloy]. The one-screw test was performed to quantify the vertical misfits using an optic microscope. The loosening torque for the prosthetic screws was measured 24 hours after the tightening torque (10 Ncm) using a digital torque meter. Data were analyzed by two-way ANOVA and Tukey’s test (α=0.05). Results: Overall, dentures with passive fit and Ti screws resulted in significantly higher loosening torque of the prosthetic screws (p<0.05). No significant interaction was found between fit level and screw material (p=0.199). The prosthetic screw material and fit of implant-supported dentures have an influence on screw joint stability. Ti screws presented higher joint stability than Au screws and minimum of misfit should be found clinically to improve the mechanical behavior of the screw joint. PMID:20148135

  7. Colonisation of dentures by Staphylococcus aureus and MRSA in out-patient and in-patient populations.

    PubMed

    Lewis, N; Parmar, N; Hussain, Z; Baker, G; Green, I; Howlett, J; Kearns, A; Cookson, B; McDonald, A; Wilson, M; Ready, D

    2015-09-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen, and colonisation with this organism can result in localised or systemic infections which may be fatal. One hundred in-patients admitted to a London teaching hospital and 100 out-patients attending prosthetic dentistry clinics were recruited into this study. Of the 100 out-patients, 27 % harboured S. aureus on their dentures, compared to 33 % of in-patients. Only one out-patient had MRSA colonising their dentures whereas 12 % of the in-patients harboured MRSA. The median total bacterial count of the denture plaque samples was 6.2 × 10(7) cfu/sample and 6.9 × 10(7) cfu/sample for the out-patient and in-patient populations, respectively. In most instances, where present, S. aureus comprised less than 1 % of the total viable denture microbiota. Phage typing demonstrated that EMRSA-15 and non-typeable strains were harboured on dentures. The results of this study have revealed that dentures are a potential reservoir of MRSA and so account should be taken of these findings when planning decontamination procedures for elimination of this pathogen. PMID:26071000

  8. Prevalence of denture-related oral lesions among patients attending College of Dentistry, University of Dammam: A clinico-pathological study

    PubMed Central

    Mubarak, Suhayla; Hmud, Ali; Chandrasekharan, Suresh; Ali, Aiman A.

    2015-01-01

    Background: Heterogeneous groups of oral lesions are likely to develop among denture wearers. The objectives of this study were to determine the exact prevalence of oral lesions among denture wearers attending the clinics of the College of Dentistry, University of Dammam. Materials and Methods: All denture wearers attending the dental clinics in the period between January 2012 and April 2013 were included in this study. Of the total 210 patients, 166 (79%) were males and 44 (21%) were females. Comprehensive oral examination was performed for all patients. Any denture-induced lesion was biopsied. Data collected were analyzed using SPSS program. Results: Oral lesions were found in 20.5% of the cases under study (43 out of the total 210 denture wearers). Denture-induced fibrous hyperplasia was the most common type of lesion detected (41.9%). A significant correlation (P = 0.004) was found between the type of denture and oral lesions in this study. Conclusion: The prevalence of denture-induced oral lesions was found to differ significantly from that reported in other studies. The diversity of these lesions among different studies depends on the quality and materials of dentures delivered, the techniques used, and the methods of patients’ instructions adopted. PMID:26759806

  9. Kidney removal

    MedlinePlus

    ... the surgical cut is located. Recovery after a laparoscopic procedure is most often quicker, with less pain. Outlook (Prognosis) The outcome is most often good when a single kidney is removed. If both kidneys are removed, ...

  10. Tick Removal

    MedlinePlus

    ... ticks Tickborne diseases abroad Borrelia miyamotoi Borrelia mayonii Tick Removal Recommend on Facebook Tweet Share Compartir If ... a tick quite effectively. How to remove a tick Use fine-tipped tweezers to grasp the tick ...

  11. Mislaid dentures: a cause for unusual presentation of bilateral vocal cord palsy

    PubMed Central

    Vallamkondu, Vamsidhar; Gatenby, Andrew; Shakeel, Muhammad; Hussain, Akhtar

    2014-01-01

    An 81-year-old man was referred urgently to the head and neck clinic with symptoms of worsening dysphagia, dysphonia and weight loss. He had a history of chronic lymphocytic leukaemia. On full ear, nose and throat examination, he was found to have fixed vocal cords with pooling of saliva in the bilateral pyriform fossa. Hypopharyngeal malignancy was suspected and further imaging was performed. Imaging also raised the suspicion of malignancy in the hypopharynx. Rigid endoscopic examination under general anaesthesia was carried out which revealed an impacted denture in the cricopharynx and upper oesophagus. The patient was aware of his loss of dentures 3 months ago (corresponds to the onset of his symptoms) but felt that he had mislaid them and had never mentioned this to anyone. We present a case highlighting a delay in diagnosis, a missed diagnosis on CT scan and an unusual presentation leading to bilateral vocal cord paresis. PMID:25139929

  12. Wear of artificial denture teeth by use of toothbrushes. Part 1: Abrasive wear of anterior teeth.

    PubMed

    Satoh, Y; Ohtani, K; Maejima, K; Morikawa, M; Matsuzu, M; Nagai, E; Toyoma, H; Ohwa, M; Ohki, K; Kaketani, M

    1990-12-01

    High-strength denture teeth (HS teeth) were developed in order to improve the hardness and wear resistance of conventional plastic denture teeth (PL teeth), while retaining their feature of easy occlusal adjustment. The objective of this study was to evaluate the abrasive wear resistance of HS teeth. We conducted wear tests and measured surface roughness using six types of anterior artificial teeth, i.e., three types of HS teeth and three types of PL teeth, the latter serving as the control. The results of the toothbrush abrasion test revealed that the HS teeth had about 5 times greater wear resistance than the PL teeth. It was also found that the type of artificial teeth and the number of abrasive wear-testing strokes had a significant (P less than 0.05) influence on the surface roughness of artificial teeth. PMID:2074493

  13. Problems Faced by Complete Denture-Wearing Elderly People Living in Jammu District

    PubMed Central

    Sharma, Sumeet; Singh, Sarbjeet; Wazir, Nikhil; Raina, Rajiv

    2014-01-01

    Context: Poor oral health is increasing dramatically among old people especially those living in rural and remote areas. Various factors such as low education background, low income, poor living conditions, unhealthy lifestyle, inadequate oral hygiene and tobacco use lead to poor oral health among older people which in turn lead to risks to their general health. The older people especially from rural areas are apprehensive about seeing a dentist and do not visit them regularly. This may lead to various problems which may have a detrimental influence on their quality of life. Aim: To know the problems faced by complete denture wearers in rural areas in Jammu district. Materials and Methods: Fifty patients from rural area Bishna, initially treated with a complete denture in the maxilla or mandibles were examined. The data were collected with the help of a questionnaire. Results: The results revealed that majority of respondents were in the age – group of 65-70 y. Majority of respondents complained of "difficulty chewing", "sore spots”, “painful and swollen gums". Majority of respondents had difficulty in speech, it was difficult for them to interact and communicate with their dentures on. Most of the respondents had lost confidence and had low self esteem. Clinical observations revealed that the commonest condition associated with denture wearing was Oral Stomatitis/ Burning mouth Syndrome, Superimposed infection and Angular cheilitis. Conclusion: Older people should Communicate and visit dentists, regularly, so that the dentists can adjust the treatment and pace according to their needs. Behavioural therapy techniques can make dental visits relatively anxiety and pain-free. PMID:25654025

  14. In vitro Effects of Lemongrass Extract on Candida albicans Biofilms, Human Cells Viability, and Denture Surface

    PubMed Central

    Madeira, Petrus L. B.; Carvalho, Letícia T.; Paschoal, Marco A. B.; de Sousa, Eduardo M.; Moffa, Eduardo B.; da Silva, Marcos A. dos Santos; Tavarez, Rudys de Jesus Rodolfo; Gonçalves, Letícia M.

    2016-01-01

    The purpose of this study was to investigate whether immersion of a denture surface in lemongrass extract (LGE) has effects on C. albicans biofilms, human cell viability and denture surface. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were performed for LGE against C. albicans. For biofilm analysis, discs were fabricated using a denture acrylic resin with surface roughness standardization. C. albicans biofilms were developed on saliva-coated discs, and the effects of LGE at MIC, 5XMIC, and 10XMIC were investigated during biofilm formation and after biofilm maturation. Biofilms were investigated for cell counting, metabolic activity, and microscopic analysis. The cytotoxicity of different concentrations of LGE to peripheral blood mononuclear cells (PBMC) was analyzed using MTT. The effects of LGE on acrylic resin were verified by measuring changes in roughness, color and flexural strength after 28 days of immersion. Data were analyzed by ANOVA, followed by a Tukey test at a 5% significance level. The minimal concentration of LGE required to inhibit C. albicans growth was 0.625 mg/mL, while MFC was 2.5 mg/mL. The presence of LGE during biofilm development resulted in a reduction of cell counting (p < 0.05), which made the MIC sufficient to reduce approximately 90% of cells (p < 0.0001). The exposure of LGE after biofilm maturation also had a significant antifungal effect at all concentrations (p < 0.05). When compared to the control group, the exposure of PBMC to LGE at MIC resulted in similar viability (p > 0.05). There were no verified differences in color perception, roughness, or flexural strength after immersion in LGE at MIC compared to the control (p > 0.05). It could be concluded that immersion of the denture surface in LGE was effective in reducing C. albicans biofilms with no deleterious effects on acrylic properties at MIC. MIC was also an effective and safe concentration for use. PMID:27446818

  15. In vitro Effects of Lemongrass Extract on Candida albicans Biofilms, Human Cells Viability, and Denture Surface.

    PubMed

    Madeira, Petrus L B; Carvalho, Letícia T; Paschoal, Marco A B; de Sousa, Eduardo M; Moffa, Eduardo B; da Silva, Marcos A Dos Santos; Tavarez, Rudys de Jesus Rodolfo; Gonçalves, Letícia M

    2016-01-01

    The purpose of this study was to investigate whether immersion of a denture surface in lemongrass extract (LGE) has effects on C. albicans biofilms, human cell viability and denture surface. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) were performed for LGE against C. albicans. For biofilm analysis, discs were fabricated using a denture acrylic resin with surface roughness standardization. C. albicans biofilms were developed on saliva-coated discs, and the effects of LGE at MIC, 5XMIC, and 10XMIC were investigated during biofilm formation and after biofilm maturation. Biofilms were investigated for cell counting, metabolic activity, and microscopic analysis. The cytotoxicity of different concentrations of LGE to peripheral blood mononuclear cells (PBMC) was analyzed using MTT. The effects of LGE on acrylic resin were verified by measuring changes in roughness, color and flexural strength after 28 days of immersion. Data were analyzed by ANOVA, followed by a Tukey test at a 5% significance level. The minimal concentration of LGE required to inhibit C. albicans growth was 0.625 mg/mL, while MFC was 2.5 mg/mL. The presence of LGE during biofilm development resulted in a reduction of cell counting (p < 0.05), which made the MIC sufficient to reduce approximately 90% of cells (p < 0.0001). The exposure of LGE after biofilm maturation also had a significant antifungal effect at all concentrations (p < 0.05). When compared to the control group, the exposure of PBMC to LGE at MIC resulted in similar viability (p > 0.05). There were no verified differences in color perception, roughness, or flexural strength after immersion in LGE at MIC compared to the control (p > 0.05). It could be concluded that immersion of the denture surface in LGE was effective in reducing C. albicans biofilms with no deleterious effects on acrylic properties at MIC. MIC was also an effective and safe concentration for use. PMID:27446818

  16. [Foreign dentures and dental tourism--willingness-to-pay and factors influencing the demand for foreign dental prosthesis in Germany].

    PubMed

    Köberlein, J; Klingenberger, D

    2011-07-01

    With the progressive realisation of the single European market, public interest has been directed towards cross-border healthcare services to an increasing extent. More and more dentures are being imported into Germany from foreign countries. Furthermore, patients are becoming ever more mobile, travelling to other countries to receive prosthetic treatment from dentists. The objective of this evaluation was to determine by means of a dedicated questionnaire the patients' individual preferences for foreign dentures and the potential savings. 1 368 individuals between the ages of 30 and 75 years were interviewed within a representative omnibus survey. The evaluation of the individual willingness-to-pay included 4 treatment scenarios, which were assessed by the participants in a "bidding game". Participants could choose between a "crown scenario" and an "implant scenario", both with the subcategories "foreign dentures" and "dental tourism". The direct comparison revealed a preference for the "foreign dentures" option over "dental tourism". Average willingness-to-pay for the dental tourism option in the crown scenario was calculated as 80 Euro, and in the implant scenario as 280 Euro less in comparison with the willingness-to-pay for the foreign dentures option. The willingness to switch to a less expensive dentist was one of the main determinants in the causal explanation for the variance in willingness-to-pay. Quality proved to be the decisive criterion and was indicated by 92.4% participants. A lower price for dentures played a subordinate role and was only stated as the decisive factor by 31.1% participants. In conclusion, the results clearly indicate that the decision for or against foreign dentures and the extent of willingness-to-pay depends on a range of criteria, of which "price" is only one and not the decisive factor. PMID:20571980

  17. Video-based Learning Versus Traditional Method for Preclinical Course of Complete Denture Fabrication

    PubMed Central

    Fayaz, Amir; Mazahery, Azita; Hosseinzadeh, Mohammad; Yazdanpanah, Samane

    2015-01-01

    Statement of the Problem Advances in computer science and technology allow the instructors to use instructional multimedia programs to enhance the process of learning for dental students. Purpose The purpose of this study was to determine the effect of a new educational modality by using videotapes on the performance of dental students in preclinical course of complete denture fabrication. Materials and Method This quasi-experimental study was performed on 54 junior dental students in Shahid Beheshti University of Medical Sciences (SBMU). Twenty-five and 29 students were evaluated in two consecutive semesters as controls and cases, respectively for the same course. The two groups were matched in terms of "knowledge about complete denture fabrication" and "basic dental skills" using a written test and a practical exam, respectively. After the intervention, performance and clinical skills of students were assessed in 8 steps. Eventually, a post-test was carried out to find changes in knowledge and skills of students in this regard. Results In the two groups with the same baseline level of knowledge and skills, independent T-test showed that students in the test group had a significantly superior performance in primary impression taking (p= 0.001) and primary cast fabrication (p= 0.001). In terms of anterior teeth set up, students in the control group had a significantly better performance (p= 0.001).  Conclusion Instructional videotapes can aid in teaching fabrication of complete denture and are as effective as the traditional teaching system. PMID:26106631

  18. In vitro activities of natural products against oral Candida isolates from denture wearers

    PubMed Central

    2011-01-01

    Background Candida-associated denture stomatitis is a frequent infectious disease. Treatment of this oral condition is difficult because failures and recurrences are common. The aim of this study was to test the in vitro antifungal activity of pure constituents of essentials oils. Methods Eight terpenic derivatives (carvacrol, farnesol, geraniol, linalool, menthol, menthone, terpinen-4-ol, and α-terpineol), a phenylpropanoid (eugenol), a phenethyl alcohol (tyrosol) and fluconazole were evaluated against 38 Candida isolated from denture-wearers and 10 collection Candida strains by the CLSI M27-A3 broth microdilution method. Results Almost all the tested compounds showed antifungal activity with MIC ranges of 0.03-0.25% for eugenol and linalool, 0.03-0.12% for geraniol, 0.06-0.5% for menthol, α-terpineol and terpinen-4-ol, 0.03-0.5% for carvacrol, and 0.06-4% for menthone. These compounds, with the exception of farnesol, menthone and tyrosol, showed important in vitro activities against the fluconazole-resistant and susceptible-dose dependent Candida isolates. Conclusions Carvacrol, eugenol, geraniol, linalool and terpinen-4-ol were very active in vitro against oral Candida isolates. Their fungistatic and fungicidal activities might convert them into promising alternatives for the topic treatment of oral candidiasis and denture stomatitis. PMID:22118215

  19. Evaluating surface roughness of a polyamide denture base material in comparison with poly (methyl methacrylate).

    PubMed

    Abuzar, Menaka A; Bellur, Suman; Duong, Nancy; Kim, Billy B; Lu, Priscilla; Palfreyman, Nick; Surendran, Dharshan; Tran, Vinh T

    2010-12-01

    Polyamide denture base materials are more flexible than the commonly used poly (methyl methacrylate) (PMMA). However polishability of polyamides has not been examined adequately. This study investigated the surface roughness (Ra) and clinical acceptability of samples of a polyamide denture base material and PMMA fabricated by injection moulding and traditional heat processing systems, respectively. Half of each sample surface was polished using the conventional technique (lathe with pumice followed by high shine buffs) and the other half was left unpolished. A profilometer was used to measure Ra along 3 tracks on each surface before and after polishing. Two-way ANOVA was used to compare the two surfaces of the two materials for variations in Ra values. Polyamide denture base material when polished with conventional laboratory technique became more than 7 times smoother whereas processed PMMA when polished became more than 20 times smoother using the same polishing technique. However the surface roughness of polyamide is well within the accepted norm of 0.2 µm Ra. Polyamide produces a clinically acceptable smoothness after conventional polishing by lathe. PMID:21206160

  20. Comparative adaptation accuracy of acrylic denture bases evaluated by two different methods.

    PubMed

    Lee, Chung-Jae; Bok, Sung-Bem; Bae, Ji-Young; Lee, Hae-Hyoung

    2010-08-01

    This study examined the adaptation accuracy of acrylic denture base processed using fluid-resin (PERform), injection-moldings (SR-Ivocap, Success, Mak Press), and two compression-molding techniques. The adaptation accuracy was measured primarily by the posterior border gaps at the mid-palatal area using a microscope and subsequently by weighing of the weight of the impression material between the denture base and master cast using hand-mixed and automixed silicone. The correlation between the data measured using these two test methods was examined. The PERform and Mak Press produced significantly smaller maximum palatal gap dimensions than the other groups (p<0.05). Mak Press also showed a significantly smaller weight of automixed silicone material than the other groups (p<0.05), while SR-Ivocap and Success showed similar adaptation accuracy to the compression-molding denture. The correlationship between the magnitude of the posterior border gap and the weight of the silicone impression materials was affected by either the material or mixing variables. PMID:20675954