Periapical Microsurgery: Do Root Canal-retreated Teeth Have More Dentinal Defects?

INTRODUCTION: This microsurgical clinical study evaluated if teeth that have undergone endodontic retreatment are associated with more dentinal defects than primary root canal-treated teeth. METHODS: One hundred fifty-five patients who underwent periapical microsurgery treatment in a private practice setting were evaluated. The root ends were resected, and the roots were inspected for the presence of dentinal defects through the surgical operating microscope with the help of a 0.8-mm-diameter light-emitting diode probe light and methylene blue dye. The root canal treatment history (primary vs retreatment) of the teeth was documented and related to the presence or absence of dentinal defects. Bivariate analysis was performed using the chi-square test, and a multivariate analysis was performed using logistic regression to evaluate possible confounding effects of patient age, sex, and tooth location on the association between treatment and the presence of dentinal defects. RESULTS: Of the 155 treated teeth, 33 were excluded (3 fractured and 30 missing treatment history). Of the remaining 122 included teeth, 73 (59.8%) had undergone primary root canal treatment and 49 (40.2%) retreatment. Sixteen teeth (22.5%) of the primary root canal group versus 33 (64.7%) of the retreatment group had dentinal defects. The proportion of retreated teeth with dentinal defects compared with primary treatment was statistically significant (P < .001) with a higher proportion of retreated teeth having dentinal defects. In the multivariate analysis, only the type of treatment was statistically significant (P < .001). CONCLUSIONS: This clinical study showed that root canal-retreated teeth are associated with more dentinal defects than primary root canal-treated teeth.