Microcomputed tomography evaluation of contamination with endodontic obturation material remnants in teeth with different root canal anatomy after post space preparation.

STATEMENT OF PROBLEM: Whether the amount of the endodontic obturation material remnants in a root canal prepared for a post is related to variations in the anatomic shape of the canal or whether it varies in different parts of the post space is unclear.

PURPOSE: The purpose of this in vitro study was to estimate the extent of root canal contamination with remnants of the obturation material after post space preparation in relation to the anatomic shape of the root canals by means of microcomputed tomography.

MATERIAL AND METHODS: Fifty freshly extracted teeth were divided into 5 test groups with respect to the root anatomy of different tooth types. The root canals were shaped and obturated with gutta percha. The space for the glass fiber post was prepared with standardized drills, and all specimens were scanned by microcomputed tomography. The areas of residual obturation material on the root canal walls in the coronal and apical parts of the prepared post space were estimated by using 3D visualization software. Parametric and nonparametric dispersive analysis (analysis of variance and Kruskal-Wallis) and Wilcoxon tests were used for statistical data evaluation (α=.05).

RESULTS: The estimates of the root canal surface areas contaminated with residual obturation material after post space preparation were significantly larger in premolars (P≤.01), as compared with mandibular incisors and with the palatal roots of maxillary first molars. The contamination areas in different parts of the root canal (apical and coronal) reported significant differences within and between the test groups.

CONCLUSIONS: The extent of root canal contamination with remnants of endodontic obturation material after post space preparation was related to the anatomic shape of the roots and varied in the coronal and apical parts of the prepared post space.