title: Microcomputed tomographic analysis of the furcation grooves of maxillary first premolars.
abstract: OBJECTIVE
  The aims of this study were to conduct a morphometric analysis on the buccal furcation grooves in freshly extracted bifurcated maxillary first premolars (MFPs) and to correlate all anatomical measurements using microcomputed tomography.
  
  
  METHODS
  Twenty-three human MFPs with bifurcated canals were selected for this study. The specimens were analyzed with microcomputed tomography. The length, the beginning, and the ending of the grooves were measured. The minimum cross-sectional canal wall thickness in the grooves was located, and the width of the dentin thickness was calculated. All measurements were recorded and statistically analyzed.
  
  
  RESULTS
  The concavity of the grooves begins before the bifurcation site in 9/23 samples and after the bifurcation in 56.5% of samples. The groove length varied between 1.1-9 mm; the cross-sectional area with minimum palatal dentin thickness was 0.78±0.14 mm, which was located at a mean distance of 7.1 mm from the cementoenamel junction (CEJ) and 1.38 mm from the furcation.
  
  
  CONCLUSIONS
  The presence of the furcation grooves in the palatal aspects of the buccal roots of the MFPs was 100%. The length, depth, location, and width of the dentin thickness of the grooves varied in relation to tooth length, bifurcation, and CEJ. These parameters should be taken into consideration before any endodontic or restorative procedures are performed. Reducing dentin width too vigorously by intracanal instrumentation can predispose to vertical root fractures or perforations; if a post cannot be avoided, it should not extend 6.5 mm from the CEJ.
authors.affiliation: Armed Forces Hospital, Riyadh City, Saudi Arabia.
authors.forename: Saad Misfer
authors.initials: SM
authors.lastname: Al-Shahrani
authors.forename: Dina
authors.initials: D
authors.lastname: Al-Sudani
authors.forename: Majed
authors.initials: M
authors.lastname: Almalik
authors.forename: Gianluca
authors.initials: G
authors.lastname: Gambarini
authors.forename: Faisal Ahmed
authors.initials: FA
authors.lastname: Alrumaihi
keywords: Buccal furcation groove; maxillary premolar; microcomputed tomography; morphometric analysis