RESUMEN
INTRODUCTION: The present study quantitatively assessed tissue regeneration after regenerative endodontic procedures (REPs) with 2 different apical preparation sizes in mature teeth using magnetic resonance imaging (MRI). METHODS: Eighteen maxillary anterior mature necrotic teeth with periapical lesions were selected for the study. The teeth were randomly allocated into 2 groups. Canal preparation was performed using Protaper Next files (Dentsply Sirona, York, PA) until size X3 and X5 in the test and control groups, respectively. REPs were performed, and Biodentine (Septodont, Saint-Maur-des-Fossés, France) was used as the cervical plug material. In both groups, MRI was used to measure the signal intensity (SI) of the regenerated tissue at 3, 6, and 12 months at both the middle and the apical thirds of the canal. The SI between the normal contralateral teeth and each successive interval was compared. Clinical examination, sensibility tests, and digital periapical radiographs were also performed at successive time intervals. Statistical analysis was performed using the Student t test and Cochran test. The level of significance was set at P ≤ .05. RESULTS: All 18 teeth were symptom free with healing of the periapical lesions. Regarding the SI measurements, there was no statistically significant difference between the SI of the normal contralateral teeth and that of the regenerated tissues in the treated teeth after a 12-month follow-up. In both groups, more than 60% of the cases regained pulp sensibility after 12 months. CONCLUSIONS: Vital pulplike tissue could be successfully regenerated in mature teeth using REPs, which was not significantly affected by the size of the apical diameter. MRI could successfully assess this tissue in a quantitative, noninvasive manner.