The relative frequency of periapical lesions in teeth with root canal-retained posts

This study was concerned with the relation between technical quality of root filling seal in teeth with posts and radiographic status of the periapical tissues. Full-mouth series from 298 randomly chosen patients were examined by two observers. Endodontic treatment had been performed in 852 roots and posts were observed in 424 of these. Periapical radiolucencies were judged to be present in 16% of roots with posts and in 13% of roots without posts. Roots with posts in which the remaining root filling was shorter than 3 mm showed a statistically significant higher frequency of periapical radiolucencies (p less than 0.01). It was found that an improper seal was more unfavorable in roots with posts (p less than 0.05). The findings in this study indicate that the placement of a post will not per se decrease the probability of periapical healing. It also suggests that the remaining root filling must not be shorter than 3 mm.