Effect of Three Heating Guns on the Temperature of Two Bulk-Fill Resin-Based Composites.

Objective: To evaluate the effect of three heating guns-Phasor (Vista Apex, Racine, USA), VisCalor (VOCO, Cuxhaven, Germany), and Compex HD (AdDent Inc. Danbury, USA)-on the temperature changes of two bulk-fill resin-based composites (RBCs): VisCalor Bulk (VBF, VOCO) and Filtek One Bulk Fill Restorative (OBF, Solventum, St. Paul, USA).

Materials and methods: Temperature changes were measured using a thermal camera (PI 640i, Optris Infrared Measurements, Berlin, Germany) during insertion and photocuring in a simulated proximal box of a Class II cavity and within the RBC capsules during heating. The RBCs were photocured using the Bluephase PowerCure (Ivoclar, Schaan, Liechtenstein) for 20s. Data were analyzed using repeated measures ANOVA and Tukey's test for each RBC (α = 0.05). The temperature of the RBCs at the same depth were analyzed by t-test (α = 0.05).

Results: OBF heated with Compex produced the lowest temperature rise at the pulpal floor (2.7°C ± 0.4°C), while VBF heated with Phasor produced the highest (8.8°C ± 2.4°C). The greatest temperature increases were at the top of the restoration. OBF heated with Phasor reached 48.6°C ± 4.7°C. The Phasor and VisCalor produced two temperature peaks in the RBC inside the capsule, while the Compex maintained a steady peak temperature.

Conclusion: The heating gun and RBC produced different temperatures when heating, inserting, and light-activation of the RBCs.

Clinical significance: The choice of RBC and heating gun can substantially affect the temperature of the RBC and influence its handling properties.