Microinfiltra？？o em dentes decíduos em fun？？o de materiais restauradores e condicionamento ácido

the purpose of this research was to evaluate microleakage on proximal restorations of primary teeth, using four materials (dyract, vitremer, z100 and fuji ii lc). acid etching was performed in only one group. proximal cavities were prepared with the following measures (mm): height, 4; width, 3; depth, 2. restoring was performed according to manufacturer？s instructions, and specimens were stored in distilled water for seven days, at 37oc. afterwards, thermal cycling was performed (700 cycles at 5 and 55oc, for one minute in each temperature). specimens were then immersed in 0.5% methylene blue solution, and prepared for evaluation. the results led to the following conclusions: there were great differences of scores between materials, 0.1 (dyract) and 4.0 (fuji ii lc); vitremer and z100 presented similar values (respectively, in scores, 1.7 and 1.6); fuji ii lc presented the largest microleakage, which decreased with the acid etching.