RESUMO
BACKGROUND: With the increase in various resin-based composites with varying monomeric formulations and fi llers had led to a significant number of problems, and one of such is postoperative pain. Clinician is in a dilemma what to select and what not to. The latest nanocomposite is there for a short while that no individual research is available currently, hence, this study was undertaken. The aim of this present study was to assess the cuspal deflection at each stage of polymerization for the incremental restoration of standardized large (mesio occlusal distal [MOD]) cavities with three posterior restorative resins. And also to assess the cervical microleakage. MATERIALS AND METHODS: 18 extracted upper premolar teeth were selected. Teeth were divided into three groups (A, B, and C), each group consisting six teeth, large (MOD) cavity preparation was done. Groups A, B, and C were restored with P60, Filtek supreme (3M, ESPE), and ormocer material (Admira:Voco). The lingual cusps of the extracted teeth were approximated to the receptor of a compactor - deflection measuring gauge, following each stage of polymerization using light emitting diode curing light a measurement of the cuspal deflection was recorded. The restored teeth were prepared for microleakage testing and were examined under stereomicroscope at ×25 for the extent of the cervical gingival microleakage. RESULTS: The cuspal deflection was the greatest for Filtek P60 and least for filtek supreme - nanocomposite with ormocer ranked between the two. For the microleakage, none of the materials were identified as producing less gingival microleakage. CONCLUSION: The lesser cuspal deflection values with filtek supreme nanocomposite could be due to resin chemistry and also filler particle size. Hence, this nanocomposite could be the first choice of material for use in large esthetic restorations.
