The Effect of Reinforcement of Coronal Flared Root Canals on Fracture Resistance
The purpose of this study is to compare fracture resistance of coronal flared root canal teeth using difference restorative methods. A total of 40 permanent maxillary central incisors were decoronated by diamond bur. The root canals were instrumented , filled with guttapercha and root canal cement, then prepared for post fabrication by FRC-Postec® plus drill No.1 . Ten teeth were prepared for cast post & core (control group). Thirty teeth were flared at the coronal part of the canals then divided into 3 groups. Group 1 was fabricated with morphologic cast post & core. Group 2 was reinforced intraradicular with resin composite before making cast post & core. Group 3 was intraradicular reinforced with resin composite before fixing fiber reinforced composite post. All groups were fracture resistance tested by using universal testing machine (Instron® 5566 ). The fracture resistance were evaluated statistically by Kruskal-Wallis test and Mann-Whitney U test. The results showed that intraradicular reinforcement with resin composite and cast post & core group has no statistically significant difference in fracture resistance compare with control group but higher than the other methods significantly (p<0.05).
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