Micro-computed Tomographic Analysis of the Efficacy of 3 Techniques for Removal of Calcium Hydroxide from the Mesial Canals of Curved Mandibular Molars.

INTRODUCTION

The purpose of this study was to evaluate the efficacy of 3 irrigation techniques: standard syringe irrigation (SI), ProUltra PiezoFlow (CUI), and EdgeEndo Er,Cr:YSGG (LAI) laser in removing calcium hydroxide from the mesial canals of severely curved mandibular molars using micro-computed tomography (micro-CT) analysis.

METHODS

Mesial canals of 30 extracted human mandibular molar teeth were prepared to size 30/.04 taper or 35/.04 taper rotary instruments. Teeth were randomly assigned to the 3 experimental groups (n = 10) with evenly distributed degrees of curvature. Calcium hydroxide was placed into prepared canals and sealed for 14 days. A micro-CT scan was taken to determine calcium hydroxide paste volume in each tooth. Canals were irrigated utilizing the 3 techniques and re-scanned. Micro-CT volume and percent change of calcium hydroxide before and after irrigation were calculated and analyzed.

RESULTS

Calcium hydroxide paste remained in all groups after irrigation. The SI group removed -0.09% in the apical segment (0-3 mm) and 14% in the middle segment (3-6 mm). CUI removed 15% in the apical segment and 50% in the middle segment. LAI removed 49% in the apical segment and 72% in the middle segment.

CONCLUSIONS

Irrigation with LAI removed significantly more calcium hydroxide in the middle and apical segments when compared to CUI and SI.