Influence of post-thickness and material on the fracture strength of teeth with reduced coronal structure

• Published in: Journal of conservative dentistry 2013-03, Vol.16 (2), p.139-143
• Main Authors: Bacchi, Ataís, Fernandes dos Santos, Mateus, Pimentel, Marcele, Caetano, Conrado, Sinhoreti, Mário Alexandre, Consani, Rafael Leonardo
• Format: Article
• Language: English
• Subjects: Dentin; Injuries; Original; Studies; Teeth
• ISSN: 0972-0707; 0974-5203
• DOI: 10.4103/0972-0707.108196

Purpose: To evaluate the fracture strength of endodontically treated teeth with reduced coronal structure reinforced with glass-fiber posts and cast posts and core (nickel-chromium alloy) with different thickness. Materials and Methods: Forty maxillary central incisors were sectioned at 1 mm of the cementoenamel junction and endodontically treated. The teeth were divided into four groups ( n = 10) and restored with cast post and core and glass-fiber posts with diameters of 1.5 mm and 1.1 mm. The fracture strength was evaluated using a Universal Testing Machine (Instron 1144) at 45° of angulation. The results were submitted to analysis of variance two-way and Tukey′s test ( P < 0.05). The failure mode was also evaluated. Results: Cast post and core were statistically superior to the glass-fiber posts with the self-post diameter ( P = 0.001). When the self-post material was considered, no significant difference was observed between the two post-diameters ( P = 0.749). The glass-fiber post-groups presented more fractures in the cervical third than the cast post and core groups. Conclusion: Teeth restored with cast post and cores present higher fracture strength than those reinforced with glass-fiber posts. An increased post-thickness does not increase the fracture strength. Glass-fiber posts lead to less severe fractures.