Abstract

PACHAS M, Roberto J; ANDRADE, José Humberto  and  GARCIA SIVOLI, Carlos. Influencia del biselado de los márgenes cavo-superficiales en la desadaptación marginal mostrada por restauraciones posteriores de composite. Acta odontol. venez [online]. 2008, vol.46, n.3, pp.295-299. ISSN 0001-6365.

Marginal deterioration is one the most frequent composite restoration failures at posterior teeth with chewing function. The type of configuration factor at cavosurface margins could affect marginal deterioration levels; however, available information is somewhat contradictory. Objective: To determine the influence of three cavosurface margin preparations (butt-joint, bevelled-edge, and concave bevel -chamfer style-) on marginal degradation found in direct composite restorations applied to posterior teeth under compressive strength. Materials and Methods: Sixty recently extracted human posterior teeth (30 upper bicuspid teeth and 30 upper third molars) were randomly distributed into three groups, having 10 bicuspid teeth and 10 molar teeth each group. Each tooth had standardized Class I slot cavities and was prepared according to the cavosurface margin preparations above mentioned (group 1=butt-joint, group2=bevelled-edge, group 3=concave bevel); then, it received direct packable composite restoration. All teeth were thermocycled 1500x at 5/55 degrees C, cycled 4000x of compressive loading at a maximum strength of 300kN and a frequency of 5Hz. Results: Video loupe analyses of occlusal surfaces from the study sample did not show statistically significant differences (p=0.139) among the three cavosurface margin preparations studied.

Keywords : marginal deterioration; bevel; composite; posterior restoration; compressive loading.