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Published on: March 7, 2014
Photoelastic stress analysis of endodontically treated teeth restored with different post systems: normal and
Jinbao Ma1, Hiroyuki Miura, Daizo Okada
1Fixed Prosthodontics, Department of Restorative Sciences, Graduate School, Tokyo Medical and Dental University.
Abstract:
The present study examined the influence of different post materials and their lengths on the mechanical stress of endodontically treated incisor roots in two alveolar bone conditions. Two-dimensional photoelastic models were fabricated to simulate the endodontically treated maxillary central incisors restored with three kinds of posts materials (low Young's modulus glass fiber post, high Young's modulus glass fiber post, and prefabricated stainless steel post) and two post lengths (8 and 4 mm). Completed models were placed in a transmission polariscope and loaded with a static force of 150 N at 45° to the tooth axis. Photoelastic photographs and the magnitudes of fringe order revealed stress distribution in the root, and suggest that the glass fiber post with a low Young's modulus and long length can reduce the stress concentration both in normal and alveolar bone resorption conditions.
