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Updated: Jun 14, 2026

Shrinkage of Dental Composite in Simulated Cavity Measured with Digital Image Correlation
Published on: July 21, 2014
Modulated photoactivation of composite restoration: measurement of cuspal movement using holographic interferometry
Larisa Blažić1, Dejan Pantelić, Svetlana Savić-Šević
1Faculty of Medicine, Clinic of Dentistry of Vojvodina, University of Novi Sad, Hajduk Veljkova 12, 21000, Novi Sad, Serbia. larisa@eunet.rs
Abstract:
The purpose of this research was to investigate the influence of modulated photoactivation on cuspal movement. Eight class II MOD composite restorations were analyzed under various photoactivation protocols in a real-time manner using holographic interferometry. During the first photoactivation protocol, the composite restoration was illuminated for 200 s continuously. In the second protocol, the polymerization lamp was first turned on for 5 s, then turned off for 120 s, and again turned on for a final 195 s. In both protocols, radiant exposure was the same. A significant decrease (p < 0.05) in cuspal deflection was found for two-step irradiation (average value of total cuspal deflection was 5.03 ± 0.62 µm) compared to continuous irradiation (average value of total cuspal deflection was 5.95 ± 0.65 µm). The two-step photoactivation protocol was found preferable, since it resulted in a significantly lower cuspal deflection (11% lower, compared to the continuous illumination).

