Fracture resistance of nanofilled composite resin restoration for the treatment of incisally fractured incisors:An in vitro study / 实用口腔医学杂志

ABSTRACT

Objective:To study the fracture resistance of nanofilled composite resin restoration for the treatment of incisally fractured in-cisors. Methods:30 extracted permanent maxillary central incisors were randomly divided into A, B and C groups (n=10). In group A and B, the teeth were cut obliquely from the mesial incisal angle. Labial reduction of 0. 5 mm for veneer and dovetails in the lingual surfaces were prepared. In group A, additional 2mm of the incisal edge were cut horizontally. The teeth were restored with nanofilled com-posite resin. The samples in group C were unprepared as the controls. The specimens were stored in artificial saliva and underwent 2 000 cycles of thermal cycling test. Fracture resistance of the teeth was measured by a test machine and the fracture mode was observed. Re-sultsThe mean fracture load(N) of group A, B and C was 466.93 ±171.68, 444.5 ±173.00 and 474.77 ±97.55 respectively(P>0. 05). All fractures in the 2 test groups but 1 in the control group were in a favorable way. Conclusion:Incisally fractured incisors restored with nanofilled composite resins can achieve the fracture resistance similar to that of intact natural tooth. Failure modes of the restored teeth are in favorable way. Additional cut of 2 mm of the incisal edge dose not affect the fracture resistance of the restored teeth.