A retrospective evaluation of radiographic outcomes in immature teeth with necrotic root canal systems treated with regenerative endodontic procedures.

INTRODUCTION: Several case reports on endodontic regeneration involving immature permanent teeth have recently been published. These case series have used varying treatments to achieve endodontic regeneration including triple antibiotic paste, Ca(OH)(2), and formocresol. However, no study has analyzed the overall results.
METHODS: In this retrospective study, we collected radiographs from 54 published and unpublished endodontic regenerative cases and 40 control cases (20 apexification and 20 nonsurgical root canal treatments) and used a geometrical imaging program, NIH ImageJ with TurboReg plug-in, to minimize potential differences in angulations between the preoperative and recall images and to calculate continued development of root length and dentin wall thickness.
RESULTS: The comparison to the 2 control groups provided a validation test for this method. Forty-eight of the 54 regenerative cases (89%) had radiographs of sufficiently similar orientation to permit analysis. The results showed regenerative endodontic treatment with triple antibiotic paste (P < .001) and Ca(OH)(2) (P < .001) produced significantly greater increases in root length than either the MTA apexification or NSRCT control groups. The triple antibiotic paste produced significantly greater differences in root wall thickness than either the Ca(OH)(2) or formocresol groups (P < .05 for both). The position of Ca(OH)(2) also influenced the outcome. When Ca(OH)(2) was radiographically restricted to the coronal half of the root canal system, it produced better results than when it was placed beyond the coronal half.
CONCLUSIONS: Ca(OH)(2) and triple antibiotic paste when used as an intracanal medicament in immature necrotic teeth can help promote further development of the pulp-dentin complex.