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

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. 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 (alpha = 0.05). 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. It can be concluded that mandibular free-end RPD wearers show smaller and more precise movements than mandibular complete denture wearers.

Influence of Post and Resin Cement on Stress Distribution of Maxillary Central Incisors Restored with Direct Resin Composite

The current study evaluated the influence of two endodontic post systems and the elastic modulus and film thickness of resin cement on stress distribution in a maxillary central incisor (MCI) restored with direct resin composite using finite element analysis (FEA). A three-dimensional model of an MCI with a coronary fracture and supporting structures was performed. A static chewing pressure of 2.16 N/mm(2) was applied to two areas on the palatal surface of the composite restoration. Zirconia ceramic (ZC) and glass fiber (GF) posts were considered. The stress distribution was analyzed in the post, dentin and cement layer when ZC and GF posts were fixed to the root canals using resin cements of different elastic moduli (7.0 and 18.6 GPa) and different layer thicknesses (70 and 200 mu m). The different post materials presented a significant influence on stress distribution with lesser stress concentration when using the GF post. The higher elastic modulus cement created higher stress levels within itself. The cement thicknesses did not present significant changes.

Perception of eating practices and stages of change among Brazilian adolescents

Objective. To evaluate the perception of eating practices and the stages of change among adolescents. Methods. Cross-sectional study involving a representative sample of 390 adolescents from 11 public schools in the city of Piracicaba, Brazil, in 2004. Food consumption was identified by a food frequency questionnaire and the perception of eating practices evaluation was conducted by comparing food consumption and individual classification of healthy aspects of the diet. The participants were classified within stages of change by means of a specific algorithm. A reclassification within new stages of change was proposed to identify adolescents with similar characteristics regarding food consumption and perception. Results. Low consumption of fruit and vegetables and high consumption of sweets and fats were identified. More than 44% of the adolescents had a mistaken perception of their diet. A significant relationship between the stages of change and food consumption was observed. The reclassification among stages of change, through including the pseudo-maintenance and non-reflective action stages was necessary, considering the high proportion of adolescents who erroneously classified their diets as healthy. Conclusion. Classification of the adolescents into stages of change, together with consumption and perception data, enabled identification of groups at risk, in accordance with their inadequate dietary habits and non-recognition of such habits. (C) 2009 Elsevier Inc. All rights reserved.

Patterns of food acquisition in Brazilian households and associated factors: a population-based survey

Objective: To identify food acquisition patterns in Brazil and relate them to the sociodemographic characteristics of the household. Design: A cross-sectional national Household Budget Survey (HBS). Principal component factor analysis was used to derive food patterns (factors) on the basis of the acquisition of food classified into thirty-two food groups. Setting: The source of data originates from the 2002-2003 HBS carried out by the Brazilian Institute of Geography and Statistics between June 2002 and July 2003 using a representative sample of all Brazilian households. Subject: A total of 48 470 households allocated into 443 strata of households that were geographically and socio-economically homogeneous as a study unit. Results: We identified two patterns of food acquisition. The first, named `dual`, was characterized by dairy, fruit, fruit juice, vegetables, processed meat, soft drinks, sweets, bread and margarine, and by inverse correlations with Brazilian staple foods. In contrast, the second pattern, named `traditional`, was characterized by rice, beans, manioc, flour, milk and sugar. The `dual` pattern was associated with higher household educational level, income and the average age of adults on the strata, whereas the `traditional` presented higher loadings in less-educated households and in the rural setting. Conclusions: Dietary patterns described here suggest that policies and programmes to promote healthy eating need to consider that healthy and non-healthy foods may be integral in the same pattern.

Self-rated oral health and associated factors in Brazilian elders

Objective: Self-rating provides a simple direct way of capturing perceptions of health. The objective of this study was to estimate the prevalence and associated factors of poor self-rated oral health among elders. Methods: National data from a cross-sectional population-based study with a multistage random sample of 4786 Brazilian older adults (aged 65-74) in 250 towns were analysed. Data collection included oral examinations (WHO 1997) and struct-ured interviews at elderly households. The outcome was measured by a single five-point-response-scale question dichotomized into `poor` (fair/poor/very poor) and `good` (good/very good) self-rated oral health. Data analyses used Poisson regression models stratified by sex. Results: The prevalence of poor self-rated oral health was 46.6% (95% CI: 45.2-48%) in the whole sample, 50.3% (48-52.5) in men and 44.2% (42.4-46) in women. Higher prevalence ratios (PR) were found in elders reporting unfavourable dental appearance (PR = 2.31; 95% CI: 2.02-2.65), poor chewing ability (PR = 1.64; CI: 1.48-1.8) and dental pain (PR = 1.44; CI: 1.04-1.23) in adjusted analysis. Poor self-perception was also associated with being men, black, unfavourable socioeconomic circumstances, unfavourable clinical oral health and with not using or needing a dental prosthesis. Conclusion: Assessment and understanding of self-rated oral health should take into account social factors, subjective and clinical oral symptoms.

Chemical Composition and Antimicrobial Activity of the Essential Oil from Croton heterocalyx Baill. (Euphorbiaceae s.s.) Leaves

The chemical composition and the antimicrobial activity of the essential oil from Croton heterocalyx leaves were evaluated. The oil which was analyzed by GC and GUMS was found to contain germacrene D (12.5%), bicyclogermacrene (11.2%), delta-elemene (9.2%) beta-elemene (8.2%), spathulenol (6.9%), linalool (5.4%) and 1,8-cineole (3.7%) its major components. Croton. heterocalyx oil displayed a high inhibitory activity against the fungi Aspergillus niger (16404) and Candida albicans (ATCC 10231.) as well its the Gram-positive bacterium Staphylococcus aureus (ATCC 6538), hut a very weak activity was observed for the Gram-negative bacteria Escherichia coli (ATCC 8739) and Pseudomonas aeruginosa (ATCC 9027).

Nutrition-related habits and associated factors of Brazilian adolescents

To investigate the nutrition-related habits (NRH) of Brazilian adolescents and evaluate the associations with risk factors.Cross-sectional school-based was carried out among high school adolescents aged 14-18 years (n = 1,759) from public and private schools from two cities. The NRH were investigated by the weekly consumption of vegetables, fruit, sweet food and fried food. Risk factors investigated were: city, sex, age, socioeconomic status and nutritional status. In statistics, Poisson regression was used with robust variance adjustment.Data indicated low consumption of fruits and vegetables, 70.0 and 71.0%, respectively, and high consumption of sweets and fried food, 66.7 and 63%, respectively. Boys showed risk of inadequate intake of vegetables [prevalence ratios (PR) 1.10, 95% CI 1.01-1.16] and fruit (PR 1.09, 95% CI 1.01-1.16). Furthermore, adolescents who live in Maringa had greater likelihood of consuming vegetables and fruit (20 and 25%, respectively). However, they presented risk of inadequate consumption of sweets (PR 1.19, 95% CI 1.11-1.28) for adolescents who live in Presidente Prudente.We concluded that inadequate NRH show high prevalence among adolescents and indicate the need to employ educational strategies that promote the adoption of more healthy habits and behaviors.

Percepção dos idosos sobre saúde bucal

The assessment of oral health status in elderly patients is essential for the development of specific health policies. The prevalence of oral diseases is high in this population. The self-perception of oral health conditions influences the demand for oral care and quality of life for seniors. The aim of this study was to assess self-perception of oral health status in 100 elderly of both sexes, aged 60 years or older and functionally independent the Basic Health Unit of Felipe Camarão II, Natal, Brazil. For comparison of self-perception data was collected in Bom Pastor, Natal / RN. In this research data were collected a questionnaire grouped into two parts. The first part with the socio-demographic data, subjective and objective condition of oral health and access to the service, the second part GOHAI Index. This index consists of 12 items that make it possible to obtain information involving aspects of chewing, speech, phonation, and self-assessed oral health. The results were subjected to statistical tests of Mann-Whitney and Kruskal-Wallis test (α = 0.05), to identify possible predictors of self-evaluation. As a result, 69% were female, ages ranged from 60 to 86 years, with a median of 65 years. In relation to marital status 48% were married. For the years of study, the sample had an average of 3 years. For the last visit to the dentist, only 27% of seniors had visited the Dentist for less than a year. Regarding the questions about the presence of gingival and dental problems were answered by 46% and 21% respectively. The data on the perception of your teeth and gums, 44%. The index showed GOHAI value for self-perception of 30 points to Felipe Camarão and 28 points for the Bom Pastor, both considered a low perception. We identified predictors of self-rated number of people in the room, participate in any associational activity, there is problems with your teeth and your gums. Concluded a negative self-perception of oral health condition by Gone in both areas, influenced by socioeconomic and cultural issues, although they realize the importance given to oral health, but by the misfortunes of other prominent favored little valuing of oral health

Temporomandibular Joint Vibration Before and After Exercises and Occlusal Splints

Temporomandibular joint (TMJ) sounds are frequent in patients. The aim of this study was to analyze patients with clicking at the end of opening and at the beginning of closing their mouths treated by muscular exercises through chewing and by occlusal splints. Fifteen patients with clinically verified clicking and TMJ and 15 patients without sounds were selected by the Research Diagnostic Criteria for Temporomandibular Disorders. They were submitted to electrovibratography at consultation and 60 and 120 days of treatment by occlusal splints and exercises. Patients demonstrated significant reduction of TMJ sounds after treatment, but vibration intensity was not similar with that of the control group after 120 days.

Electromyographic activity of the mandible muscles at the beginning and end of masticatory cycles in patients with complete dentures

The aim of this study was to assess the electrical activity of the masseter and anterior temporal muscles in subjects with severe bone resorption at two different times: ( a) the initial period, with the complete dentures they had worn for over 10 years, and (b) the final period, 5 months after having new dentures put into place. Twelve asymptomatic subjects were asked to respond to the questionnaire, according to the research diagnostic criteria for temporomandibular disorders, before denture rehabilitation and 5 months after the new dentures were put in place. The electrical activity of the muscles was recorded during mastication in the initial and final period, using artificial food (Optocal). The operator monitored the 35 chewing cycles that were repeated to grind the artificial food. After wearing the new dentures for 5 months, the right anterior temporal muscle showed a statistical difference before and after denture rehabilitation at the beginning and end of mastication. Muscular capacity and ability reduced the electrical activity in the masseter muscles after rehabilitation. Copyright (c) 2008 S. Karger AG, Basel.

Silent Period of Masticatory Cycles in Dentate Subjects and Complete Denture Wearers

Purpose: The purpose of this study was to assess, through electromyographic activity (EMG), the silent period (SP) of masseter and anterior temporal muscles in dentate subjects (DS) and complete denture wearers (CDW).Materials and Methods: The evaluations were performed at the initial and final period of the mastication for the DS group. For the CDW group, the evaluations were performed at the initial period of mastication, with old complete dentures worn for more than 10 years (OCDW) and at the final period of the mastication with new complete dentures (NCDW), 5 months after rehabilitation. Twenty-four asymptomatic subjects (12 DS, 12 CDW) answered a questionnaire based on the Research Diagnostic Criteria for temporomandibular disorders. The CDW group answered the questionnaire before and after new denture insertion and after 5 months of rehabilitation. The SP of the muscles was recorded through EMG at the initial and final periods of mastication using artificial food (Optocal). The operator monitored 35 chewing cycles performed to grind the artificial food and selected eight open-close-clench-chewing cycles for the record.Results: The SP of the muscles analyzed with new complete dentures showed no statistical difference in comparison to the old dentures. There was a statistically significant difference in the SP between the CDW and DS groups for initial and final chewing.Conclusion: Lowered muscular capacity and ability reduced the SP of muscles after rehabilitation with NCDWs.

Surgical and Prosthetic Rehabilitation of Patients With Hemimandibular Defect

Purpose: This work intended to investigate, by means of a literature revision, the techniques and materials used for the rehabilitation of hemimandibular defect patients, prosthetic and occlusal aspects of these patients, and chewing and swallowing.Materials and Methods: For the confection of this revision, we consulted the database indexers Google Scholar, PubMed, and SciELO and found studies published between the periods 1972 and 2008. The terms used for the search had been "to hemimandibular defects," "to temporomandibular joint protheses," and "vascularized cap grafts," which had been searched separately and combined.Conclusions: Diverse techniques and materials used for the reconstruction of hemimandibular defects exist; however, great bone resorption is still observed, which will compromise the prosthetic rehabilitation of these patients. More prospective works and stories of clinical cases duly registered will be able to elucidate in a clearer form the anatomic and functional devolutions of the verbal socket of hemimandibular defect patients.

Effect of salivary stimulation on erosion of human and bovine enamel subjected or not to subsequent abrasion: An in situ/ex vivo study

This in situ/ex vivo study evaluated whether saliva stimulated by chewing gum could prevent or reduce the wear and the percent change in microhardness (%SMH) of bovine and human enamel submitted to erosion followed by brushing abrasion immediately or after 1 h. During 2 experimental 7-day crossover phases, 9 previously selected volunteers wore intraoral palatal devices, with 12 enamel specimens (6 human and 6 bovine). In the first phase, the volunteers immersed the device for 5 min in 150 ml of cola drink, 4 times per day (at 8, 12, 16 and 20 h). Immediately after the immersions, no treatment was performed in 4 specimens, 4 other specimens were immediately brushed (0 min) using a fluoride dentifrice, and the device was replaced into the mouth. After 60 min, the remaining 4 specimens were brushed. In the second phase, the procedures were repeated, but after the immersions, the volunteers stimulated the salivary flow rate by chewing a sugar-free gum for 30 min. Changes in wear and %SMH were measured. ANOVA and Tukey's test showed statistical differences (p < 0.05) for the following comparisons. The chewing gum promoted less wear and %SMH. A decreasing %SMH and an increasing enamel wear were observed in the following conditions: erosion only, 60 min and 0 min. The human enamel presented greater %SMH and less wear compared to bovine enamel. The data suggest that the salivary stimulation after an erosive or erosive/abrasive attack can reduce the dental wear and the %SMH.

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

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Fracture resistance of endodontically treated teeth with different heights of crown ferrule restored with prefabricated carbon fiber post and composite resin core by intermittent loading

This study evaluated the fracture resistance of endodontically treated teeth restored with prefabricated carbon fiber posts and varying quantities of coronal dentin. Sixty freshly extracted upper canines were randomly divided into groups of 10 teeth each. The specimens were exposed to 250,000 cycles in a controlled chewing simulator. All intact specimens were subjected to a static load (N) in a universal testing machine at 45 degrees to the long axis. Data were analyzed by 1-way analysis of variance and Tukey test (alpha = .05). Significant differences (P < .001) were found among the mean fracture forces of the test groups (positive control, 0 mm, 1 mm, 2 mm, 3 mm, and negative control groups: 1022.82 N, 1008.22 N, 1292.52 N, 1289.19 N, 1255.38 N, and 1582.11, respectively). These results suggested that the amount of coronal dentin did not significantly increase the fracture resistance of endodontically treated teeth restored with prefabricated carbon fiber post and composite resin core. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;106:e52-e57)