The aim of this study was to examine the edentulism rates in Brazil and make projections for the next years. Data were collected from three national oral health surveys. The percentage of edentulous jaws was calculated. Projections were made for the years 2020, 2030 and 2040, assuming that edentulism follows a logistic function. Population projections were also performed. Annual change in proportion of edentulous jaws was -0.04% for teenagers, -0.96% for adults and 0.76% for the elderly. By 2040, edentulous jaws will be virtually zero among teenagers, 1.77% among adults and 85.96% among the elderly. Teenagers will slightly decrease in number; adults will increase and subsequently decrease; the elderly will continue to increase. In teenagers and adults, the number of edentulous jaws will decrease, being approximately 616,000 in 2040. In the elderly, it will increase alarmingly, reaching over 64 million in 2040. Edentulism is declining in Brazil among teenagers and middle-aged adults, but is still increasing and will continue to increase for the next decades among the elderly.

Occlusal factors, especially the presence of wear facets, should be considered in the management of noncarious cervical lesions.

Purpose:The purpose of this study was to assess noncarious cervical lesions in young patients and to establish a possible relation with occlusal aspects. Materials and Methods:Forty-eight dental students (28 males; 20 females) between the ages of 16 and 24 years, were investigated to verify the presence of noncarious cervical lesions and their relation to some occlusal aspects. The assessment involved a questionnaire, clinical examinations, and model analysis. Results:The results indicated that the lower first molars (21.3%), the upper first molars (16.0%), the upper first premolars (12.8Y0), the lower first premolars (1 1.7%), and the lower second premolars (1 1.7%) were the teeth most affected by the lesions. Age was a significant factor with respect to the presence of lesions; the students with noncarious cervical lesions were older than the students who showed no lesions. Among the 79 teeth exhibiting lesions, 62 (78.5%) showed wear facets. In the group with lesions, the mean, per subject, was 15.0 teeth with wear facets, whereas in the group without lesions the mean was 10.8 teeth with wear facets per subject, suggesting that occlusal stress has some effect on lesion development. CLINICAL SIGNIFICANCENoncarious cervical lesions are characterized by loss of tooth structure on the cervical area of the tooth and can result in esthetic problems for the patient, as well as discomfort due to the hypersensibility that often occurs at the location of the lesion. The results obtained reinforce the multifactorial theory, shared by several authors, for the etiology of such lesions. However, as the limitations of each etiologic agent begin to be understood, there will be a decrease in the possibility of misleading interpretations of the result of present or future investigations. 33. Jarvinen GK, et al. Risk factors in dental erosion. J Dent Res 1991; 70942-947.

No abstract

Removal torque values tended to decrease as the number of insertion/removal cycles increased, for both groups. Comparisons of the slopes and the intercepts between groups showed no statistical difference. There was no significant difference between the mean values of last five cycles and the 11th cycle. Within the limitations of this in vitro study, it was concluded that (1) repeated insertion/removal cycles promoted gradual reduction in removal torque of screws, (2) replacing the screw with a new one after 10 cycles did not increase resistance to loosening, and (3) removal of the hexagon from the abutment base had no effect on the removal torque of the screws.