Influence of the height of the mandibular ridge on the masticatory function during the functional adaptation with new complete dentures.

BACKGROUND: The period of functional adaptation to a new conventional complete denture embraces many transitory issues, and this period is directly related to the rehabilitation success. OBJECTIVE: This clinical trial evaluated the influence of the height of mandibular ridge on the masticatory function of complete denture (CD) wearers during the adaptation period. METHODOLOGY: A total of 28 individuals wearing new CDs (NR, n=14, normal mandibular ridges, 64±12.5 years, 9 female; RR, n=14, resorbed mandibular ridges, 69±6.8 years, 9 female) were assessed at 24 hours, 30 days, three months and six months after the insertion of the CDs for masticatory performance (MP, sieves method), satisfaction with CDs (questionnaire) and maximum occlusal bite force (MOBF) (gnatodynamometer). The classification of the mandibular ridges followed the Kapur index. Data of MP and MOBF were analyzed by two-way ANOVA and satisfaction with CDs was analyzed by Generalized Estimating Equations (GEE), α=.05. RESULTS: Participants with NR presented better masticatory performance (p=.000 - NR 30.25±9.93%, RR 12.41±7.17%), general satisfaction (p=.047), retention of mandibular denture (p=.001), chewing ability (p=.037), and comfort of wearing a mandibular denture (p=.000). Regardless of the mandibular ridge, MP (p=.000) was higher at three (21.26±12.07%) and six months (24.25±12.26%) in comparison to 24 hours (18.09±10.89%), the MOBF (p=.000) was higher at three months (78.50±6.49 N) compared to 24 hours (57.34±5.55 N) and 30 days (62.72±5.97 N), and the comfort of wearing a mandibular denture (p=.002) at three months (1.61 ± 0.07) was greater than 24 hours (1.29±0.10) and 30 days (1.36±10). CONCLUSIONS: The study suggests that the participants with NR have higher MP and satisfaction with their CD, regardless of the follow-up period after the insertion of the new CD. After subjects received the CD, a period of 3 months was necessary for achieving better achievement MOBF, MP, and self-perceived comfort with the mandibular denture, regardless of the height of the mandibular ridge.

Influence of the height of the mandibular ridge on the masticatory function during the functional adaptation with new complete dentures

Abstract The period of functional adaptation to a new conventional complete denture embraces many transitory issues, and this period is directly related to the rehabilitation success. Objective This clinical trial evaluated the influence of the height of mandibular ridge on the masticatory function of complete denture (CD) wearers during the adaptation period. Methodology A total of 28 individuals wearing new CDs (NR, n=14, normal mandibular ridges, 64±12.5 years, 9 female; RR, n=14, resorbed mandibular ridges, 69±6.8 years, 9 female) were assessed at 24 hours, 30 days, three months and six months after the insertion of the CDs for masticatory performance (MP, sieves method), satisfaction with CDs (questionnaire) and maximum occlusal bite force (MOBF) (gnatodynamometer). The classification of the mandibular ridges followed the Kapur index. Data of MP and MOBF were analyzed by two-way ANOVA and satisfaction with CDs was analyzed by Generalized Estimating Equations (GEE), α=.05. Results Participants with NR presented better masticatory performance (p=.000 - NR 30.25±9.93%, RR 12.41±7.17%), general satisfaction (p=.047), retention of mandibular denture (p=.001), chewing ability (p=.037), and comfort of wearing a mandibular denture (p=.000). Regardless of the mandibular ridge, MP (p=.000) was higher at three (21.26±12.07%) and six months (24.25±12.26%) in comparison to 24 hours (18.09±10.89%), the MOBF (p=.000) was higher at three months (78.50±6.49 N) compared to 24 hours (57.34±5.55 N) and 30 days (62.72±5.97 N), and the comfort of wearing a mandibular denture (p=.002) at three months (1.61 ± 0.07) was greater than 24 hours (1.29±0.10) and 30 days (1.36±10). Conclusions The study suggests that the participants with NR have higher MP and satisfaction with their CD, regardless of the follow-up period after the insertion of the new CD. After subjects received the CD, a period of 3 months was necessary for achieving better achievement MOBF, MP, and self-perceived comfort with the mandibular denture, regardless of the height of the mandibular ridge.

A Randomized Clinical Trial of Oral Health-Related Quality of Life, Peri-Implant and Kinesiograph Parameters in Wearers of One-or Two-Implant Mandibular Overdentures.

PURPOSE: The present randomized clinical trial compared the oral health-related quality of life (OHRQoL), peri-implant parameters, mandible movements, and maxillary complete denture movement during chewing between wearers of single- (1-IOD) and wearers of two-implant overdentures (2-IODs) for a period of 12 months. MATERIALS AND METHODS: Twenty-one complete denture wearers were randomly allocated into two parallel groups: 1-IOD (n = 11) or 2-IODs (n = 10). The validated Brazilian version of the OHIP-EDENT was used to evaluate the OHRQoL. A kinesiograph recorded maxillary complete denture movement during chewing of hard food testing (polysulphide impression material) and soft food testing (bread). Peri-implant parameters were also recorded: plaque index (PI), bleeding on probing (BOP), and probing depth (PD). The Friedman test was used to compare the OHRQoL data and peri-implant parameters among periods; the Mann-Whitney test was performed to compare the groups (1- and 2-IODs). One-way ANOVA and the Bonferroni test were used to compare mandible movement during chewing among periods, and the t-test for independent samples was used to compare the groups. Maxillary complete denture movement was analyzed using three-way ANOVA followed by the Bonferroni test. All statistical analyses were performed at α = 0.05. RESULTS: Both treatments led to better general OHRQoL in comparison to conventional complete dentures (p < 0.001). Better OHRQoL was observed among 2-IOD patients at the 12-month follow up (p = 0.034). Peri-implant parameters were similar irrespective of the group and follow-up period. Vertical opening was significantly higher among 1-IOD patients at 3 months (p = 0.038). Decreased maxillary denture vertical intrusions were observed with complete dentures in comparison with overdentures (p = 0.006), regardless of the food test (p = 0.251); however, vertical intrusion was significantly higher among 1-IOD patients (p = 0.043). CONCLUSIONS: This study suggested that 1-IOD can improve patient OHRQoL and may be similar to 2-IODs in preservation of both peri-implant parameters and masticatory movements.

Evaluation of methods for stain removal in acrylic resin denture teeth: in vitro study / Avaliação de métodos de remoção de manchas em dentes de resina acrílica para prótese total: estudo in vitro

Introduction: The staining of artificial teeth can be related to the acrylic resin abrasion caused by brushing, resulting in higher deposition of dyes from the beverage, and consequently higher aesthetic damage. Objective: The aim of this in vitro study was to evaluate methods for removal of stains from acrylic denture teeth using spectrophotometric analysis. Material and method: Artificial teeth were divided into twelve groups (n=10) according to the type of treatment (re-polishing - Re or immersion in Corega Tabs - Sp), staining solutions, coffee (Cf) and Coca-Cola® (Cc) or water (W) and with/without toothbrushing (B). The Sp specimens were submitted to seven immersion cycles (5 min each). The Re specimens were polished with pumice stone followed by Spain white paste. Color differences (ΔE) were captured by a spectrophotometer: T0 (baseline), T1 (after brushing/immersion in solutions) and T2 (after Re or Sp). Result: Statistically significant color change between T1 and T2 (paired T-test; α =.05) was observed for the group CfSp (p=.032); and for the groups BWRe (p=.000), BCfRe (p=.049) and CcRe (p=.042). Higher color changes were observed for the specimens submitted to toothbrushing (ANOVA two way; p<.001). Conclusion: It could be concluded that the immersion in sodium perborate (Corega Tabs) can be used for removal of coffee stains from denture teeth, and re-polishing for removal of Coca-Cola® stains. Still, toothbrushing produced greater color changes on denture teeth, regardless of the immersion solution.

Introdução: O manchamento dos dentes artificiais pode estar relacionado à abrasão da resina acrílica provocada pela escovação, resultando na maior deposição de corantes provenientes de bebidas, e consequentemente maior prejuízo estético. Objetivo: O objetivo do presente estudo foi avaliar métodos de remoção de manchas extrínsecas por meio de analise com espectofotômetro. Material e método: Dentes artificiais foram divididos em 12 grupos (n=10), de acordo com o tipo de tratamento (repolimento – Re ou imersão em perborato de sódio, Corega Tabs – Sp), tipo de solução de manchamento, café (Cf) ou Coca-Cola® (Cc) ou água (W) e com/sem escovação (B). Os métodos de remoção de manchas propostos (Re e Sp) foram realizados de acordo com protocolos pré-estabelecidos. Os espécimes Sp foram submetidos a 7 ciclos de imersão (5 minutos cada). O repolimento foi realizado com pastas de pedra pomes e branco de espanha, utilizando escovas de cerdas macias e rodas de feltro. As leituras de estabilidade de cor (ΔE) foram realizadas por meio de um espectrofotômetro: T0 (baseline), T1 (após escovação/imersão em bebidas), e T2 (após Re ou Sp). Resultado: Alterações de cor entre T1 e T2 (teste T pareado; α=0,05) foram observadas para o grupo CfSp (p=.032); e para os grupos BWRe (p=.000), BCfRe (p=.049) e CcRe (p=.042). Os dentes artificiais submetidos à escovação mostraram maior alteração de cor (ANOVA 2 fatores; p<0,001). Conclusão: Conclui-se que a imersão em perborato de sódio (Corega Tabs) pode ser utilizada para remoção de manchas de café e o repolimento para remoção de manchas de Coca-Cola®. Ainda, a escovação produziu as maiores alterações de cor nos dentes artificiais, independentemente da solução de imersão.

Mandibular kinesiographic pattern of women with chronic TMD after management with educational and self-care therapies: A double-blind, randomized clinical trial.

STATEMENT OF PROBLEM: Limited mandibular movements are one of the most important signs of temporomandibular disorders (TMDs) and may cause functional difficulties. PURPOSE: The purpose of this double-blind, randomized clinical trial was to evaluate the effect of treatment with only educational or education associated with self-care therapies on the pattern of mandibular movements of women with chronic painful TMDs. MATERIAL AND METHODS: Forty-two women were selected and randomly divided into 3 groups, control group (CG, n=13), education group (EG, n=16), and education and self-care group (ESG, n=13), according to the sequence of treatment they received. A kinesiograph device recorded mandibular movements during maximum mouth opening and mastication at baseline (T0) and at 30-day (T1) and 60-day (T2) follow-up. Kinesiographic data were statistically analyzed using 1-way ANOVA, followed by the Bonferroni test for multiple comparisons of means (α=.05). RESULTS: The ESG group demonstrated an improvement in the maximum vertical opening (MVO= 5.1 ±3.4 mm; P=.012) and anteroposterior mandibular movement (MAM) during maximum opening (7.4 ±9.5; P=.019), significantly higher than that of the EG (MVO=1.8 ±3.5 mm; MAM=0.8 ±5.0 mm) and the CG (MVO=0.9 ±3.8 mm; MAM=0.8 ±4.4 mm) after 30 days of follow-up. Moreover, at T1, vertical mandibular movement during mastication was significantly higher in the ESG group (17.4 ±1.7 mm) than in the EG group (15.0 ±2.8, P=.027). No significant differences were found between the women who received treatment with educational and self-care therapies for 60 days and the women who received this treatment for 30 days. CONCLUSIONS: In the short-term, education and self-care treatment positively influenced the mandibular movement pattern of women with chronic painful TMDs.

In Vitro Assessment of the Abrasion Resistance of Two Types of Artificial Teeth Submitted to Brushing.

PURPOSE: To assess the effect of brushing with different solutions on the abrasion resistance of two types of acrylic resin teeth. MATERIALS AND METHODS: Maxillary premolars from two types of acrylic teeth (Biotone and Biotone IPN) were divided into six groups (n = 12), according to the solution used during brushing: distilled water (control), coconut soap, or dentifrice. A mechanical brushing machine was used to simulate approximately 1 year of brushing (11,000 strokes). The weight loss (WL) of teeth was obtained from the difference between the initial (IW) and final weight (FW) of each specimen, and the mean of percentage of weight loss (PWL) was calculated for each group. Data were analyzed using the Kruskal-Wallis test, followed by Bonferroni's post-test comparison (α = 0.05). RESULTS: A statistically significant difference was found for the factor solution (p < 0.001). Brushing using dentifrice caused the highest values of weight loss (-0.50%), in comparison with the groups brushed with coconut soap (0.00%) or distilled water (0.00%). CONCLUSIONS: For both types of artificial teeth, brushing with dentifrice produced higher abrasion than brushing with coconut soap or water.

Bond Strength of Artificial Teeth Attached to a Microwave-Polymerized Denture Base Resin after Immersion in Disinfectant Solutions.

PURPOSE: To evaluate the bond strength between two types of acrylic resin teeth and a microwave denture base resin after immersion in disinfectant solutions for 180 days. MATERIALS AND METHODS: Eighty specimens made of acrylic resin teeth (Biotone and Biotone IPN) attached to a microwave polymerized denture base resin (Nature-Cryl MC) were divided into eight groups (n = 10) according to the treatment (distilled water-control, 2% chlorhexidine digluconate, 1% sodium hypochlorite and sodium perborate solution-Corega Tabs). The shear strength tests (MPa) were carried out using a universal testing machine with a 0.5 mm/min speed. Data analysis was performed using ANOVA and multiple comparison Student-Newman-Keuls post hoc test (α = 0.05). RESULTS: Biotone IPN showed similar results among the groups (distilled water, 8.25 ± 1.81 MPa; chlorhexidine, 7.81 ± 3.34 MPa; hypochlorite, 7.75 ± 3.72 MPa; and Corega Tabs, 7.58 ± 2.27 MPa, whereas Biotone showed significantly lower shear bond strength values for the groups immersed in Corega Tabs (5.25 ± 3.27 MPa) and chlorhexidine (6.08 ± 2.35 MPa). CONCLUSIONS: Soaking the dentures in 1% sodium hypochlorite could be recommended as a disinfectant solution for dentures fabricated with conventional acrylic resin denture teeth and microwave denture base resin. For dentures fabricated with IPN teeth and microwave denture base resin, all the soaking solutions evaluated in this study could be suggested to denture wearers.

Crossover clinical trial of different methods of removing a denture adhesive and the influence on the oral microbiota.

STATEMENT OF PROBLEM: The difficulty of removing denture adhesive is a common problem reported by users of these products. PURPOSE: The purpose of this clinical study was to investigate the effectiveness of different cleaning protocols for removing a denture adhesive (DA) and the influence on the oral microbiota. MATERIAL AND METHODS: Twenty participants wearing well-fitting complete dentures were instructed to use a denture adhesive 3 times a day during a 4-week trial, divided into 4 stages: (A) control-3 daily denture brushings using water at ambient temperature, (B)-3 daily denture brushings using water at ambient temperature plus coconut soap, (C)-3 daily denture brushings using water at ambient temperature plus dentifrice; (D)-3 daily denture brushings using water at ambient temperature combined with immersion in sodium perborate solution for 5 minutes before nocturnal sleep. After each 1-week stage, saliva specimens were collected. A dye was used to display and quantify the remaining DA on the internal surface of the maxillary dentures as a percentage. For microbiological analysis, the saliva was diluted and plated onto Petri dishes containing a nonselective culture medium and Candida spp culture media. After the incubation period, Candida species were identified and the number of colony forming units (CFU/mL) was calculated. RESULTS: A significant difference was found among the 4 cleaning methods for the quantification of remaining DA (Friedman, P=.036). Brushing the dentures with coconut soap, dentifrice, or water combined with immersion in sodium perborate solution was more effective in removing DA than brushing with only water. The cleaning methods did not influence the quantification of microorganisms in general or Candida albicans and other Candida species in particular. CONCLUSIONS: Brushing the dentures with coconut soap, dentifrice, or water combined with immersion in sodium perborate solution was more effective for removing cream-type denture adhesive than brushing with only water.