Standardization of Endodontic Access Cavities Based on 3-dimensional Quantitative Analysis of Dentin and Enamel Removed.

Introduction: The aim of this study was to determine and compare the difference in the volume of dentin and enamel removed (DER) to prepare 3 different access cavities and to propose a standardization of the access cavities according to their volume of DER.

Methods: One hundred twenty maxillary and mandibular molars and premolars were assigned to 3 subgroups for each tooth type (n = 10): the traditional endodontic cavity (TEC) group; the conservative endodontic cavity (CEC) group with partial unroofing and convergent walls; and the ultraconservative endodontic cavity (UEC) group, preserving most part of the pulp chamber roof and the occlusal surface. The sliced image data of cone-beam computed tomographic images before and after access cavity preparation were exported as Digital Imaging and Communications in Medicine files and imported into the MeVisLab framework system (MeVis Research, Bremen, Germany). After segmentation, the volumes of coronal dentin and enamel were measured, and the difference in the percentage of volume of DER for endodontic access cavity preparation was calculated. The data were subjected to statistical analyses (analysis of variance) with a level of significance set at P < .05.

Results: The percentage of volume of DER was less than 6% for the UEC group, up to 15% for the CEC group, and more than 15% for the TEC group, with a statistically significant difference among all groups in all of the tooth types analyzed (P < .05).

Conclusions: The present study showed significantly different percentages of volume of DER among the groups analyzed (ie, UEC < CEC < TEC). A standardization of access cavity preparation was proposed according to the percentage of volume of DER.