RESUMO
OBJECTIVES: Microleakage in direct dental restorations is a primary causal factor in the restoration's failure. The aim of this study was to evaluate whether the technique for occlusal layering of the composite resin (the use of brush adaptation, the use of magnification, cusp build-up, stamp technique) has any effect on microleakage of direct restorations in occlusal cavities. MATERIALS AND METHODS: One hundred extracted human molars were restored using five restoration techniques (Packable Bulk technique, Occlusal Stamp technique, Successive Cusp Build-up technique, Successive Cusp Build-up technique + Brush adaptation, Successive Cusp Build-up technique + brush adaptation + Dental Operative Microscope magnification). The teeth were subjected to thermal aging for 800 cycles at 5°C and 55°C, infiltrated with basic fuchsin dye for 24 h, and then sectioned buccolingually in the middle of the crown. Infiltration was measured in four areas of the tooth section by five different observers and then given a score from 1 to 3, proportional to infiltration depth. RESULTS: The lowest mean scores for infiltration (meaning less infiltration observed) were present in Group A (1.41 ± 0.878) and Group C (1.46 ± 0.679), while Group D showed the highest infiltration scores (1.75 ± 0.853). When comparing the groups for differences, no statistically significant difference in infiltration was found between any technique p < .586. CONCLUSION: The techniques examined for placing the occlusal layer of composite in direct restorations do not differ significantly in terms of marginal infiltration, although a slight improvement was found when using the bulk technique and the successive cusp build-up.