A micro-computed tomographic analysis of maxillary lateral incisors with radicular grooves.

INTRODUCTION: The radicular groove is clinically significant due to its relevance to onset of inflammatory processes in the periodontal tissues. This study examined anatomic features of radicular grooves by using micro-computed tomography (micro-CT) scans.
METHODS: Eleven extracted permanent maxillary lateral incisors with radicular grooves were collected from a native Chinese population and were scanned by micro-CT scans. The specimens were reconstructed three-dimensionally by software Mimics 10.01 (Materialise, Leuven, Belgium). The grooves were classified into three types on the basis of severity.
RESULTS: Three specimens presented type I grooves (apically not beyond the coronal third of the root); five specimens showed a type II groove (beyond coronal third, corresponding to a normal or simple root canal), and three showed a type III groove (beyond the coronal third, corresponding to a complex root canal system). The developing groove could be located at the mesial (three teeth), distal (six teeth) and medial (one tooth) aspect of the root. In one specimen double grooves were found (a mesial and a distal). All specimens with type I grooves had normal root canal configuration. A cross-sectional teardrop-like canal was seen in a specimen with a type II groove. The C-shaped canal, invagination canal, and additional root with secondary canal were observed in specimens with type III grooves.
CONCLUSIONS: Understanding the anatomic features of the radicular groove is essential for successful dental treatment.