The cuspal deflection caused by dental composite polymerization shrinkage analyzed by digital holography

Background/Aim. Polymerization shrinkage of filling materials is one the main disadvantages adhesive restorative dentistry. The objective study was to measure tooth cusps deflection caused by polymerization a resin-based dental material (RDM) in real-time using digital holographic interferometry (DHI) two groups cavities restored with and without an additional wall. Simultaneously, internal mechanical behavior monitored. Methods. Standardized three class I were prepared on third molar teeth. teeth cut halves longitudinal plane, obtaining six samples for (now II cavities), divided into (group G1 ? wall, group G2 it), mounted aluminum blocks. filled RDM, cured light emitting diode (LED) 40 sec from occlusal direction, monitored during curing post-curing period DHI. Data analyzed Student's t-test independent Anderson-Darling test, alpha level 0.05. Results. At end examined period, showed significantly in-creased [t (10) = 4.7; p 0.001] compared G2. Conclusion. Within limitations this study, it concluded that presence wall simulating matrix band had significant influence increase prolonged RDM shrinkage.