Abstract
When using post materials that are more rigid than teeth for abutment construction, tooth root fracture may be caused by stress concentration in the remaining part of the tooth root. Most of the tooth root fractures clinically observed in metal post abutment cases are longitudinal fractures, resulting in tooth extraction in many cases. In cases with sufficient coronal tooth substance, post-less abutment construction has recently been considered. Fiber posts have recently attracted attention as a post material for resin abutment construction due to their flexibility with elastic modulus similar to that of dentine. In Japan, although approval by the Ministry of Health, Labour and Welfare has recently been obtained, there have been few experimental studies and clinical reports on fiber posts. In this study, we performed a breakdown test and finite element analysis of fiber posts as in vitro studies, and reviewed overseas references on clinical results. Eexperimental results show that, the effects on preventing stress concentration are high in all abutment construction methods when sufficient ferrule in the remaining teeth is present, and stress may be concentrated in the cervical area in fiber post abutment cases. Clinical results obtained from references showed that, fiber posts are superior to cast posts and commercially available metal posts, in terms of fracture and dislodgment. However, since issues were revealed in previous clinical studies, further comparison studies are necessary to evaluate the superiority of fiber posts compared with metal posts.
