Ármann Hannesson, Vilhelm Grétar Ólafsson, Jónas Geirsson
The use of pre-heated composite has become increasingly popular. The increased temperature leads to lower composite viscosity allowing for easier placement and enhanced physical properties. A review of the literature revealed no reported randomized trials comparing pre-heated and room temperature composite resin class II restorations. The objective of the study was to evaluate the clinical survival and development of quality parameters of restorations applied at different temperatures. Fifty patients in need of two class II restorations were recruited in a split mouth study. The restorative work was done by two operators at their private clinics.
The primary statistical analysis of this trial is the comparison of overall survival between the two treatments (test/control). Kaplan-Meier estimates of the survival curves for both groups were performed, and the survival curves compared using a Cox proportional hazards model with subject as a random factor in the model and treatment group as the fixed effect. At 24 months, all observed restorations were considered clinically acceptable.
The secondary statistical analysis is the comparison of change for each quality parameter from baseline. A significant difference between FDI scores at 24 months versus baseline was observed in both groups for categories surface luster, marginal staining and marginal adaptation, color match and translucency, tooth integrity, periodontal response, and adjacent mucosa. Anatomical form reached statistical significance for control restorations. No adverse events occurred during the study. There is no statistical difference between the study groups for postoperative sensitivity, highlighting the safety of the warming technique.