Correlation between factors associated with the removable partial dentures use and Candida spp. in saliva

doi: 10.1111/j.1741‐2358.2010.00390.x
Correlation between factors associated with the removable partial dentures use and Candida spp. in saliva Objectives: To correlate the presence and number of Candida spp. in the saliva of wearers of removable partial dentures retained with precision attachments with the proportion of metal/acrylic resin present in the dentures. Methods: Saliva samples from 40 removable partial denture wearers (test) and one paired sample of individuals, non‐wearers of any type of removable denture (control) were collected, seeded, and the colony forming units of Candida counted and identified. The metal/acrylic resin proportion of each denture was quantified, using silicone plates pressed over each denture. Results: Candida spp. was found in the saliva of 80% of the individuals in the test group and 65% of the control, with C. albicans being the most prevalent species. The test group presented with the highest number of colony forming units of Candida per ml of saliva, and there was weak correlation between this number and the metal and resin area of the denture (Pearson’s coefficient of correlation). Greater prevalence and a higher number of colony forming units of Candida per ml of saliva occurred in removable partial denture wearers (p = 0.04) with a weak positive correlation between the metal and resin area and the number of colony forming units of Candida per ml of saliva. However, this correlation was more significant for the area of resin.     

Maxillary complete denture movement during chewing in mandibular removable partial denture wearers

Objectives: To evaluate the pattern of maxillary complete denture movement during chewing for free‐end removable partial dentures (RPD) wearers, compared to maxillary and mandibular complete denture wearers. Materials and methods: Eighteen edentulous participants (group I) and 10 volunteers with bilateral posterior edentulous mandibles (group II) comprised the sample. Measures of mean denture movement and its variability were obtained by a kinesiographic instrument K6‐I Diagnostic System, during the mastication of bread and a polysulphide block. Data were analysed using two‐way anova (α = 0.05). Results: Upper movement during chewing was significantly lower for group II, regardless of the test food. The test food did not influence the vertical or lateral position of the denture bases, but more anterior dislocation was found when polysulphide blocks were chewed. Group II presented lower intra‐individual variability for the vertical axis. Vertical displacement was also more precise with bread as a test food. Conclusion: It can be concluded that mandibular free‐end RPD wearers show smaller and more precise movements than mandibular complete denture wearers.     

Fracture resistance of maxillary complete dentures subjected to long-term water immersion

doi: 10.1111/j.1741‐2358.2012.00616.x Fracture resistance of maxillary complete dentures subjected to long‐term water immersion Objective: This study investigated the fracture resistance of maxillary acrylic resin complete dentures subjected to long‐term water immersion. Materials and Methods: Maxillary acrylic resin complete dentures were fabricated from five denture base resins. Half of the dentures were stored in water for 50 h, and the other half were kept in water for 180 days before testing. Ten specimens were fabricated per group. The flexural load at the proportional limit (FL‐PL) of the dentures was tested. Results: A two‐way anova revealed a significant difference in FL‐PL because of the denture base material variable. There were no significant differences in FL‐PL because of the effect of water immersion and the interaction between the effect of water immersion and the denture base material. The FL‐PLs of the dentures fabricated with the two conventional heat‐processed resins, the pour‐type autopolymerizing resin and the microwave energy‐processed resin were not significantly different from each other; they were significantly higher than the light‐activated resin in regard to their FL‐PL. Conclusion: The FL‐PLs of the maxillary acrylic resin complete dentures did not change after long‐tern water immersion, and the FL‐PL of the denture fabricated from the light‐activated resin was lower than those of the other materials.     

Bonding acrylic teeth to acrylic resin denture bases: a review

Partial or complete dentures are more commonly constructed for the elderly group of the population. Teeth debonding from the dentures can be frustrating to the patients as well as the dentist. Research has been carried out and is continuing to study the issue of bonding acrylic teeth to the denture base resin. The present review takes into account the majority of research papers published in the last five decades for determining the bond strength. Selection of more compatible combinations of denture base resins and acrylic teeth may reduce the number of prosthesis fractures and the resultant repairs.     

Examination of denture-cleaning methods based on the quantity of microorganisms adhering to a denture

doi: 10.1111/j.1741‐2358.2011.00461.x Examination of denture‐cleaning methods based on the quantity of microorganisms adhering to a denture Objectives: To investigate effective denture‐cleaning methods, we examined the relationships between the quantity of microorganisms adhering to dentures and the use of a denture brush and the frequency of use of a denture cleanser. Subjects and Methods: Denture plaque was collected from the mucosal surface of the examined dentures, which were 142 and 80 upper and lower complete dentures, respectively, worn by 96 outpatients (mean age: 71.9 years) of a university hospital and 41 nursing home residents (mean age: 84.8 years). The collected microorganisms were counted in terms of isolated representative colonies that were cultured and identified using standard methods. The use of a denture brush, the frequency of use, and the type and soaking time of denture cleansers as denture‐cleaning methods were surveyed. Results: The quantity of microorganisms was significantly lower in dentures of denture brush users than in those of non‐users in the outpatients (p < 0.01, Mann–Whitney U test). The quantity of microorganisms was significantly lower in the dentures of outpatients who used a denture cleanser daily or 3–4 times a week than in those who used one once or less per month and in the dentures of nursing home residents who used one daily than in those who used one at other frequencies (p < 0.05, Kruskal–Wallis test, followed by Dunn’s Multiple Comparison test). Conclusion: Within the limitations of this study, it was concluded that the use of a denture brush and daily use of denture cleanser should be recommended to complete dentures wearers as denture‐cleaning methods that effectively reduce the quantity of microorganisms adhering to dentures.     

The oral health‐related quality of life in edentulous patients treated with Conventional complete dentures

Objective: To compare the oral health‐related quality of life (OHRQoL) between patients with both maxillary and mandibular complete denture and those with either the maxillary or the mandibular complete denture. Background: Satisfaction of denture wearers can be estimated using the OHRQoL questionnaires like the OHIP‐EDENT and the Geriatric Oral Health Assessment Index (GOHAI). Methods: Two questionnaires were used to compare the OHRQoL between edentulous patients who had conventional removable complete denture on both jaws and those who had on either one of the jaws. Result: The age of the participants ranged from 42 to 75 years, with the mean age of 58 ± 8.12 years. The mean OHIP‐EDENT scores were significantly high among those who wore conventional dentures in both jaws (54.12 ± 5.21), compared with the participants who only had denture either on upper or lower jaw (46.52 ± 7.35). It was noticed that the mean GOHAI score was significantly lower (p < 0.05) among participants who had conventional denture on both upper and lower jaw (28.25 ± 3.67), as compared to those who had conventional denture only on one arch (35.12 ± 2.11). Conclusion: Patients with complete dentures in both jaw (Group I) were less satisfied than patients with single complete denture (Group II). The result obtained in this study shows dissatisfaction with conventional dentures among edentulous patients.     

Effect of pre-processing methods on bond strength between acrylic resin teeth and acrylic denture base resin

doi: 10.1111/j.1741‐2358.2011.00480.x
Effect of pre‐processing methods on bond strength between acrylic resin teeth and acrylic denture base resin Objectives: This study evaluated the effects of various pre‐processing methods on the bond strength between resin and denture teeth. Backgrounds: Debonding of acrylic resin teeth from denture base material is a problem for patients wearing complete dentures. Materials and Methods: Four experimental groups (n = 30) were investigated by subjecting tooth–resin bonding to tensile loading. Specimens were prepared and tested according to the methods of the International Standards Organization (ISO 22112:2005) using a special assembly. Four pre‐processing surface treatments of teeth were applied: (i) ST₁, no treatment applied (control); (ii) ST₂, wax solvent (Dewaks, Faber Kimya & Ilaç, Turkey); (iii) ST₃, boiling water followed by conditioning with methyl methacrylate (MMA) monomer (Meliodent, Bayer Dental, Germany); (iv) ST₄, boiling water followed by wax solvent agent and finally MMA monomer application. Bond strength test was performed using a universal testing machine. Results: All the strength values of the test groups were within clinically acceptable limits. The lowest values were from the ST₁ group and the highest values were in the ST₄ group. Conclusions: Wax elimination methods affected bonding strength. Application of wax solvent and MMA monomer to the ridge lap surfaces of the teeth gave the best results. In clinical practice, this application procedure may decrease the bonding failure of denture teeth.     

Effect of sealer coating on mechanical and physical properties of permanent soft lining materials

doi: 10.1111/j.1741‐2358.2011.00487.x
Effect of sealer coating on mechanical and physical properties of permanent soft lining materials Objective: To evaluate the long‐term effects of sealer coating on tensile bond strength and surface roughness of soft liners. Background: Failure of the bond between resilient liners and denture base significantly compromise the dentures’ longevity. In addition, surface roughness contributes to bacterial adherence on prosthetic materials, increasing the risk of oral infections. Methods: Specimens were manufactured from four reliners [Mucopren Soft (MS), Dentuflex (DF); Soft Comfort Denso (SC) and Ufi Gel SC (USC)], distributed into 10 groups (n = 10), according to material and coating treatment. Tensile bond strength was performed after one year of ageing, while surface roughness was evaluated at 0, 1, 3, 6 and 12 ageing months. Bond strength data were submitted to two‐way anova and Tukey‐HSD tests, while roughness data were submitted to mixed model analysis for repeated measurements (p ≤ 0.05). Results: MS and DF without sealer coating presented the highest tensile bond strength. After coating, DF and SC presented increased tensile bond strength. No surface roughness difference was observed in the non‐coated groups over time, acrylic‐based reliners presented higher roughness. Among coated groups, only SC presented increased surface roughness. Acrylic‐based materials presented reduced roughness at three months. Conclusion: Surface coating was effective for acrylic reliners in maintaining their initial properties. However, sealer coating should be re‐applied every 3 months.     

Effects of denture maintenance on satisfaction levels of Taiwanese elderly using removable partial dentures: a pilot study

doi: 10.1111/j.1741‐2358.2011.00500.x
Effects of denture maintenance on satisfaction levels of Taiwanese elderly using removable partial dentures: a pilot study Objective: The aim of this study was to evaluate the correlation between patient satisfaction with removable partial dentures and denture maintenance by patients, including regular application of denture adhesives and cleansers. Background: The success of removable partial dentures depends on patient satisfaction with dentures and their regular denture maintenance. Materials and methods: Demographic information, the Oral Impacts on Daily Performance (OIDP) indicator and details of denture maintenance (including the use of denture cleansers and adhesives) were collected from 193 (41.5% men and 58.5% women) participants by using questionnaires. A dentist performed oral examinations to evaluate denture function according to the OIDP items photographically and recorded the number of remaining teeth and Kennedy’s classification. Results: Most participants were satisfied with their removable partial dentures and tended to have higher satisfaction levels than the dentist’s estimation. Further, those using denture adhesives and cleansers had higher satisfaction levels than those not using such denture maintenance. Conclusions: Appropriate education regarding denture use is important because regular denture maintenance by patients affects their degree of satisfaction with dentures, as well as the dentist’s skill and the patient’s oral condition. Dentists could use this information to predict the potential success of dentures.     

Complete denture wearing and fractures among edentulous patients treated in university clinics

doi: 10.1111/j.1741‐2358.2011.00551.x
Complete denture wearing and fractures among edentulous patients treated in university clinics Objective: The prevalence of wearing and fracture of complete dentures was evaluated among edentulous patients treated in two dental schools in Brazil. Background: Acceptance and wearing of complete dentures are related to adaptive behaviour of edentulous patients. However, one reason that could interfere with the wearing dentures is their potential to fracture, which is still a common complication in denture rehabilitation practice. Material and methods: Two hundred and twenty‐four edentulous patients rehabilitated with complete dentures from 2000 to 2005 in Araçatuba and Araraquara Dental School, University of State of São Paulo, were assessed in 2006 and 2007 to answer a questionnaire about wearing and fracture of their dentures. Statistical analysis were performed using Epi Info software and chi‐squared test to compare maxillary and mandibular data (α = 0.05). Results: Almost 26% of the patients did not wear their dentures, and among the remainder, the majority wore the maxillary denture. About 30% of the dentures were fractured, with higher prevalence in the maxillary arch (p = 0.003). Conclusions: Discontinuation of wearing dentures was quite high, especially considering the treatment which was carried out in university clinics. Prevalence of fractures was also high, greater for the maxillary denture, and was one of the main reasons for non‐wearing of complete dentures.     

Use of resin‐bonded extracoronal attachments with removable partial denture: case report

doi:10.1111/j.1741‐2358.2009.00298.x
Use of resin‐bonded extracoronal attachments with removable partial denture: case report Introduction: Resin‐bonded extracoronal attachments may be indicated for the abutment teeth of removable partial dentures, especially for anterior teeth when a cingulum rest must be provided. This type of treatment has a series of advantages such as minimal tooth reduction, supragingival margins, favourable stress distribution, and improved aesthetic appearance. Objective: To report a clinical case of oral rehabilitation using a combination of resin‐bonded extracoronal attachments joined by a Dolder bar with a removable partial denture. Case report: A 60‐year‐old male patient with only the canines in the maxillary arch was restored with a combination of resin‐bonded extracoronal attachments joined by a Dolder bar and a removable partial denture. Conclusion: Dentures with resin‐bonded extracoronal attachments can have a number of advantages over traditional clasp‐retained removable partial dentures.     

Bond strength of denture teeth to acrylic resin: effect of thermocycling and polymerisation methods

Background: Failure of bonding between acrylic resin teeth and denture base material is a considerable problem for patients who wear complete dentures. Objective: The purpose of this study was to evaluate the bond strength between acrylic resins and resin denture teeth with different thermocycling and polymerisation methods. Materials and methods: Microwave‐polymerised (Onda‐Cryl), heat‐polymerised (Clássico) and autopolymerising (Jet) acrylic resins and resin denture tooth (Biotone) were used. The acrylic resins were polymerised according to the following: (A) microwave – fast cycle, Onda‐Cryl; (B) microwave – long cycle, Onda‐Cryl; (C) microwave – manufacturer’s cycle, Onda‐Cryl; (T) water bath – long cycle, Clássico; and (Q) bench polymerisation cycle, Jet. Twenty specimens were prepared for each polymerisation method. Ten were thermocycled, and 10 did not receive thermocycling. For the purpose of the study, a shear test was used. Data were analysed with the Kruskal–Wallis test and Dunn’s multiple comparisons test (p = 0.05). Results: Cycles B, C and T were similar (p > 0.05), and had statistically higher bonding values than cycles A and Q (p < 0.05) for the thermocycled and non‐thermocycled groups. For all cycles, there were no statistically significant differences between thermocycled and non‐thermocycled groups (p > 0.05), except for cycle Q (p = 0.0038). Conclusion: Thermocycling decreased the bond strength, but not significantly for microwave and heat‐polymerised cycles. Regarding the bond strength of denture teeth to acrylic resin, the fast microwave polymerisation cycle should be avoided when polymerising Onda‐Cryl acrylic resin. In addition, Jet acrylic resin is not adequate for use in denture repair.     

Treatment protocol for denture stomatitis,prior to anatomical molding

doi: 10.1111/j.1741‐2358.2012.00661.x Treatment protocol for denture stomatitis, prior to anatomical molding Background: Microorganisms of the genus Candida have been recovered from complete dentures made of acrylic resin, with high numbers of colony forming units and species diversity, which can act as infectious agents causing chronic atrophic candidiasis (denture stomatitis). Objective: The objective of this paper is present a treatment protocol for chronic atrophic candidiasis (denture stomatitis). Materials and Methods: The work describes three cases of totally edentulous patients presenting palate stomatitis who were submitted for treatment associating denture rebasing with chemically‐activated acrylic resin, night immersion in 2.5% sodium hypochlorite and use of topical antifungals for two weeks. Results: In all cases, remission of the inflammatory process occurred. Conclusion: The proposed treatment protocol proved to be to be effective.     

The influence of age and denture wear on the size of edentulous structures

Objectives : This study was designed to evaluate the influence of age and denture use on the size of arches and residual ridges in edentulous patients. Design : At two nursing homes, maxillary and mandibular stone casts of 302 fully edentulous patients were utilized to measure the size of the arches and residual ridges, according to age and use of complete dentures. Age cohorts were divided into three groups; 60–69, 70–79, and 80–89 years old. Two hundred and forty‐nine denture wearers used complete dentures for at least 2 years before examinations. Fifty‐three non‐denture users had never worn removable prostheses. Chi‐square analysis (p<0.05) was used to establish the possible relations between the linear values and the size indexes of the ridges and arches and the two examined parameters: age and denture wear. Results : Young old patients possessed edentulous structures that were not significantly larger than elderly old patients in both the maxilla and the mandible. Non‐denture users had significantly bigger arches and ridges in both edentulous jaws than denture users. Conclusions : Young old, non‐denture users tended to have bigger residual edentulous tissues compared to elderly old patients who used complete dentures.     

Effectiveness of different cleaning agents on the adherence of Candida albicans to acrylic denture base resin

doi: 10.1111/j.1741‐2358.2010.00379.x
Effectiveness of different cleaning agents on the adherence of Candida albicans to acrylic denture base resin Objective:  To evaluate the ability of three alkaline peroxide‐type (Polident, Efferdent, Fittydent) and two mouth rinse cleaning agents (CloSYSII and Corsodyl) to inhibit Candida albicans on acrylic denture base resin. Background:  Appropriate routine cleaning of dentures is necessary to prevent denture stomatitis and maintenance of healthy supporting tissues. Materials and methods:  A total of 180 acrylic resin specimens (10 × 10 × 2 mm) were prepared and divided into six groups. Candida albicans was incubated on Sabouraud dextrose agar (SDA) at 37°C for 48 h. After dilution, a final yeast suspension of approximately 10 6 C. albicans per millimetre was prepared. Ten acrylic resin specimens for each group were placed in a sterile Petri dish covered with 20 ml of fungal suspension and incubated at 37°C for 90 min. Then, the specimens were immersed in 40 ml of the test solution at 37°C for 15, 30 and 60 min. Fungal cells adhering to acrylic resin surfaces were fixed in formaldehyde and counted microscopically. Results:  Mouth rinses showed the highest removal activity for all the treatment times and completely eliminated the adherence of C. albicans. Conclusions:  The use of mouth rinse may be a suitable method for cleaning dentures.     

In vivo biofilm formation on a soft denture liner in elderly patients with controlled diabetes

doi: 10.1111/j.1741‐2358.2010.00428.x In vivo biofilm formation on a soft denture liner in elderly patients with controlled diabetes Objectives: This in vivo study evaluated the influence of controlled diabetes on biofilm formation on a soft denture liner in elderly patients. Background: Soft denture lining materials are more susceptible to microbial colonisation than denture base acrylic resins. Especially in the elderly, several predisposing factors may accumulate leading to an increased probability of biofilm development that may result in candidiasis, a significant clinical oral disease. Materials and methods: Volunteers wearing complete dentures were divided into two groups (n = 20): diabetic patients with controlled glycaemia, and healthy patients. In both groups, a silicone‐based soft liner was placed in a recess created at the base of the maxillary dentures. Subjects cleaned the prosthesis three times a day. Biofilm formed on the liner was quantified at various time points (baseline, two, four and six weeks). Data were analysed by two‐way repeated measures anova and Tukey’s test (α = 0.05). Results: There was no statistical difference in biofilm formation for any of the time points between controlled diabetes patients and healthy patients. Conclusion: The results suggest that the control of diabetes in elderly patients provides the same levels of biofilm formation when compared to healthy individuals.     

Knowledge of prosthodontic treatment among denture-wearers and non-denture-wearers attending a dental institute in India: a survey report

Objective: Knowledge of subjects regarding prosthodontic treatment may play a role in their acceptance of the prostheses. The purpose of this survey was to assess the knowledge of prosthodontic treatment among the denture‐wearers and non‐denture‐wearers reporting to the Institute of Dental Sciences, Belgaum. Methods: A self‐designed closed‐ended questionnaire containing 14 questions was designed. Four‐hundred and nineteen subjects aged between 25 and 65 years were surveyed over a period of 2 months. Collected data were statistically analysed using chi‐squared test at a significance level of p < 0.05. Results: From the 419 subjects surveyed, 140 subjects (33.4%) were dentate and 279 subjects (66.6%) were edentulous either in the maxillary, mandibular or both arches. Among the 279 edentulous subjects, 143 (51.3%) did not use any kind of prosthesis. There was a statistically significant difference in knowledge regarding the replacement of teeth by artificial means, the number of visits required for the provision of a complete denture, problems with dentures among subjects using and not using them (p < 0.001) whereas no significant difference was found among the subjects regarding aesthetics with dentures and socializing with friends. Conclusion: Attempts should be made to raise the level of knowledge of both denture‐wearers and non‐denture‐wearers reporting to the Institute for any dental treatment.     

Effect of monomer treatment and polymerisation methods on the bond strength of resin teeth to denture base material

Background: The fracture between acrylic denture base material and artificial teeth is a common clinical occurrence in dental prosthodontic practice. Objective: To evaluate the bond strength between acrylic resins and resin denture teeth when submitted by two protocols of monomer liquid application on the tooth surface and using different polymerisation methods. Material and methods: Microwave‐polymerised (Onda‐Cryl), heat‐polymerised (Clássico) and autopolymerising (Jet) acrylic resins and a brand of resin denture teeth (Biotone) were used. The acrylic resins were polymerised according to the cycles: (A) microwave – fast cycle, Onda‐Cryl; (B) microwave – long cycle, Onda‐Cryl; (C) microwave – manufacturer’s cycle, Onda‐Cryl; (T) water bath – long cycle, Clássico and (Q) bench polymerisation cycle, Jet. Thirty specimens were prepared for each polymerisation method; 10 were packed with acrylic resin after 60 s of monomer liquid application on the tooth surface, 10 after 180 s and 10 without any monomer liquid application. For the purpose of the study, a shear test was used. anova and Tukey tests were performed to identify significant differences (α = 0.05). Results: The highest bond strength values were found for monomer surface treatments, regardless of the polymerisation cycles. The highest significant values were found for cycles B (15.4 ± 1.8 MPa), C (11.9 ± 4.9 MPa) and T (15.4 ± 2.6 MPa) for non‐treated and 60 s methylmethacrylate treated groups. Comparing the monomer liquid treatment, they did not differ significantly (p > 0.05), except for cycle A (p < 0.05). Conclusion: Chemical treatment using monomer on the tooth surface prior to the acrylic resin packing improved the bond strength between resin denture tooth and acrylic resin, regardless of monomer liquid treatment protocols. The microwavable resin, polymerised by fast cycle and autopolymerising resin should be avoided for processing denture and denture repairs, respectively.     

Biofilm formation of Candida albicans on the surface of a soft denture‐lining material

Background: Soft denture lining‐materials are more susceptible to microbial adhesion than hard denture base acrylic resin. Poor oral hygiene and Candida albicans infection are common among elderly denture wearers as these patients usually have difficulty in keeping them clean. Purpose: To evaluate the influence of the oral hygiene methods on the formation of a biofilm over a soft denture‐lining material. Material and methods: Twenty volunteers were randomly separated into two groups: G1 and G2. Ten volunteers performed daily hygiene of the prostheses with a soft toothbrush and toothpaste. The G2 performed a treatment identical to G1 but also immersed the prostheses in sodium hypochlorite 0.5% for 20 min, once a week. Quantification of the mean score values of biofilm formation at different times were statistically analysed using analysis of variance and Tukey’s test (α = 0.05). Results: G1 (0.65 ± 0.52) showed the lowest mean score values of biofilm formation. There was statistical difference between G1 and G2. The highest mean score values were found at 6 weeks (1.3 ± 1.08) and were statistically different from other times. Conclusion: The oral hygiene methods had a significant effect in the formation of the biofilm over a soft denture‐lining material.     

Eight-year mortality associated with dental occlusion and denture use in community-dwelling elderly persons

Objective: To evaluate the influence of dental occlusion, with or without the use of dentures, on mortality in community‐dwelling elderly persons. Subjects: A total of 1030 randomly selected healthy independent elderly aged 65 and over were surveyed in 1995. For the study reported here, subjects were classified into three groups according to the presence or absence of maxillo‐mandibular tooth contacts. Subjects with no maxillo‐mandibular tooth contacts were further subdivided into those with and without dentures. Methods: Data on mortality were obtained from Kure City Council in September 2003. Cox regression models were used in analysing the risk for death with gender and age as covariates. Results: Individuals whose teeth had contact in at least the bilateral premolar regions at baseline had 0.78 times (95% CI: 0.60–0.99) smaller risk for death during the succeeding 8 years than those who had no occlusion. Among those who had no occlusion with their own teeth, the risk for mortality among denture non‐users was 1.52 times (95% CI: 1.25–1.83) higher than the risk for denture users. Conclusion: These results may support the view that, in the elderly, poor dental occlusion is associated with an increased risk for mortality and that, in the edentulous, the use of dentures is associated with a decreased risk for mortality.