Anatomic Study of the Buccal Root with Furcation Groove and Associated Root Canal Shape in Maxillary First Premolars by Using Micro–Computed Tomography

IntroductionThe purpose of this study was to investigate the buccal root anatomy of bifurcated maxillary first premolars with furcation grooves and to determine the correlation between the groove depth and the buccal root canal shape by using micro–computed tomography.MethodsThirty-six bifurcated maxillary first premolars with furcation grooves were obtained from native Chinese individuals aged 17–25 years and scanned by micro–computed tomography. Basic parameters including the groove length, depth, and location were recorded. The wall thickness at different portions of the buccal roots was measured by using a customized application framework in MeVisLab software. The root canal shape was quantified by the form factor, and the correlation between the mean form factor and the maximum groove depth was analyzed.ResultsThe minimum wall thickness was less on the palatal aspect (<1 mm) than on the buccal aspect of the coronal two thirds of the buccal roots. The mean form factor value ranged from 0.72–0.91 and correlated negatively with the maximum groove depth (ρ2 = −0.641, P < .001).ConclusionsThe irregular wall thickness of buccal roots of bifurcated maxillary first premolars with furcation grooves and the related changes in the root canal shape should be considered during endodontic and prosthetic treatment.