Root fracture with dentin-retained posts

The purpose of this in vitro study was to compare the incidence of incomplete root fractures occurring in teeth with and without dentin-retained posts. Eighty extracted human mandibular canines were treated as follows: 20 teeth (controls) received pulpectomies using broaches and sodium hypochlorite; 60 teeth received endodontic therapy with laterally condensed gutta percha. Of those 60 teeth, 20 teeth received Flexi-posts, 20 received Vlock dentin-retained posts, and 20 teeth had no posts placed. All teeth were stained with 5% Oil-Red-O stain for 5 days and sectioned at four levels. The sections were then examined under a stereomicroscope at x20 power. No complete fractures were found. Incomplete fractures were found in two teeth from the endodontic treatment only group, two teeth from the Flexi-post group, and two teeth from the Vlock group. None of the teeth in the control group were fractured. Based upon these results, it was concluded that: 1) Flexi-post and Vlock post placement is no more likely to cause root fracture than is conventional endodontic therapy alone; and 2) incomplete root fractures are more likely to be found in teeth with conventional endodontic therapy than in teeth not treated endodontically.