臺大醫學院-臨床牙醫學研究所;Xiong, YuYuXiongHuang, Shih-HaoShih-HaoHuangShinno, YukoYukoShinnoFuruya, YuYuFuruyaImazato, SatoshiSatoshiImazatoFok, AlexAlexFokHayashi, MikakoMikakoHayashi2017-06-292018-07-092017-06-292018-07-092015http://ntur.lib.ntu.edu.tw//handle/246246/280548Objectives. This study aimed to investigate how use of a fiber sleeve may reduce interfacial debonding and improve fracture strength of pulpless teeth with flared root canals. ;Methods. Pulpless premolars with flared root canals were restored either with a fiber-reinforced post (FRP) alone or with an FRP wrapped in a hollow tubular fiber sleeve. A normal root restored with an FRP alone served as a control. The integrity of resin-dentin and resin-fiber interfaces in the restored roots was evaluated by a stereoscopic system after penetrating a dye. Four roots were tested for each experimental group. Fracture resistance in pulpless premolars with flared root canals restored with an FRP alone or with an FRP/sleeve combination were investigated under bonded and non-bonded conditions with static fracture testing (n = 8), and stress distribution in these restored premolars were tested by finite element analysis (FEA). ;Results. Flared root canals restored with an FRP/sleeve combination demonstrated superior integrity at the cervical resin-dentin interface to root canals with an FRP alone. Premolars with a flared root canal restored with an FRP/sleeve combination showed significantly greater fracture resistance compared with premolars restored with an FRP alone. FEA showed that once interfacial de-bonding extended to the cervical region of the root, stress concentration in the root dentin dramatically increased. ;Significance. The FRP/sleeve combination was effective in reducing debonding and, hence, improving the fracture strength of pulpless premolars with flared root canals. (C) 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.Dentin bondingFiber postFinite element analysisFlared root canalFracture strengthRoot fractureStress distribution[SDGs]SDG3Debonding; Fibers; Finite element method; Fracture; Fracture testing; Fracture toughness; Hydraulic structures; Reinforcement; Resins; Restoration; Stereo image processing; Stress concentration; ANOVA analysis; Experimental groups; Fiber interface; Fiber reinforced; Interfacial debonding; Resin-dentin interfaces; Stereoscopic systems; Tubular fibers; Canals; resin cement; anatomy and histology; dental procedure; dental restoration; finite element analysis; human; in vitro study; premolar tooth; procedures; root canal preparation; tooth crown; Tooth Fractures; tooth pulp disease; tooth root; Bicuspid; Dental Restoration Failure; Dental Stress Analysis; Finite Element Analysis; Humans; In Vitro Techniques; Post and Core Technique; Resin Cements; Root Canal Preparation; Tooth Fractures; Tooth Root; Tooth, Nonvital10.1016/j.dental.2015.09.005