Clinical evaluation of thermo-viscous and sonic fill-activated bulk fill composite restorations.

Purpose: To evaluate the clinical performance of VisCalor and SonicFill versus the conventionally applied bulk fill composite restorations in Class I cavities over 18-month follow-up periods.

Methods: 60 posterior teeth were used in this study in 20 patients (age ranging from 25-40). They were randomly divided into three equal groups (n=20) based on the type of restorative material employed. Each resin composite restorative system with the recommended manufacturer's adhesive was applied and cured according to the manufacturer's instructions. All restorations were evaluated clinically at baseline (after 24 hours), 6, 12, and 18 months according to the modified United States Public Health Service (USPHS) by two examiners for retention, marginal adaptation, marginal discoloration, secondary caries, postoperative sensitivity, color match, and anatomical form.

Results: All tested groups exhibited no significant difference regarding all the clinical evaluation criteria at all evaluation periods, except for marginal adaptation and discoloration. Marginal changes (Bravo score) were detected only after 12 months in 15% of Filtek bulk fill restorations (Group 1) only while all VisCalor bulk fill restorations in Group 2 and SonicFill 2 restorations in Group 3 recorded 100% Alpha scoring, with no statistically significant difference among the groups (P= 0.050). After 18 months, Bravo scores increased to 30% in Group 1, while 5 and 10% Bravo scores were recorded in restorations of Groups 2 and 3, respectively with a statistically significant difference (P= 0.049) among them. Marginal discoloration was observed after 12 months in Group 1 only, however, no statistically significant difference was found among the groups (P= 0.126). At 18 months, all tested groups had a statistically significant difference between them (P= 0.027).

Clinical significance: Reducing the composite viscosity either by thermo-viscous technology or by sonic activation can improve the material adaptation to the cavity walls and margins, thus improving the clinical performance.