Effect of Cavity Configuration on Postoperative Hypersensitivity of Posterior Composite Restorations
Purpose: To investigate the effect of cavity configuration (C-factor) on occurrence of postoperative hypersensitivity (POH) of posterior direct resin composite restorations. Methodology: A total of 247 direct posterior composite restorations were evaluated. 118 Class I (O) and 129 Class II (MO, DO, and MOD) restorations were placed in 139 males and females patients with a mean age of 31.58 ±8.62 years. Four types of cavity configurations were prepared on premolars and molars teeth, and their dimensions were measured using periodontal probe. The preparations were restored with a total-etch adhesive system Tetric® N-Bond and Tetric® N-Ceram resin composite (Ivoclar vivadent) using incremental packing technique. Patients were recalled at 1-, 4-, and 13-weeks to question about occurrence of POH to cold, hot, sweet stimuli, mastication and clinching, and answers were recorded using Visual Analog Scale (VAS). Data was collected and analyzed using SPSS version 16 to determine whether any relationship existed between different cavity configurations and the occurrence of POH. Results: Chi-Square and t-tests revealed no significant difference in occurrence of POH between class I and class II cavity configurations (P>0.05). At week 1- post-treatment, incidence of POH was 0.8% (1/118) in class I (O), and 1.6% (2/129) in class II (DO) restorations. The three reported restorations presented with mild to moderate (3-5 VAS) sensitivity to cold stimuli. 2/247 (0.8%) restorations were presented with hyperocclusion. No POH among MO and MOD restorations. No POH at week 4- and 13- recall visits. Conclusions: Cavity configurations (C-factor) had no influence on the occurrence of POH reported by patients at 1-, 4-, and 13-weeks post-treatment. POH expected in the high C-factor class I composite restorations were not detected. The restorative technique used resulted in excellent outcomes for class I and II cavity configurations.