Root Canal Morphology of Permanent Three-rooted Mandibular First Molars: Part II—Measurement of Root Canal Curvatures

By Gu Y, Lu Q, Wang P, Ni L.

Date: 09/2010
Journal: JOE

Summary:

  •Purpose:

To evaluate the canal curvature in three-rooted mandibular first molars, focusing on the DL root(radixentomolaris) .

•N= 25 (2 rooted), 20 (3 rooted) mandibular 1st molars.

Inclusion criteria: native Chinese, intact roots.

•Materials/Methods:

•Teeth were cleaned from soft tissue and calculus. Then scanned using micro CT at fixed resolution.

•Screen shots were taken to both clinical and proximal views. Images were calibrated.

•Curvature was measured using Schneider1 technique and Cunningham and Senia2 technique.

nclusion criteria: native Chinese, intact roots. •Materials/Methods: •Teeth were cleaned from soft tissue and calculus. Then scanned using micro CT at fixed resolution. •Screen shots were taken to both clinical and proximal views. Images were calibrated. •Curvature was measured using Schneider1 technique and Cunningham and Senia2 technique.

Most highlighted Results:

•Mean degree of curvature was close in MB(24) and ML(22) canals.

•In clinical view S shaped curvatures are 60% in DB of 3 rooted molars (2mm from apex).

•The mean angle of the second curvature was approximately twice that of the primary one.

•DL canal in the three-rooted first molars exhibited the greatest degrees of curvature.

•Degree of curvature in DL canal was significantly lower in 2 rooted molar than 3 rooted.

•Mesial canals , exhibits S shaped curvature in PV while distal canals had them in clinical view.

Clinical significance:

Appreciating canal curvatures, would help in avoiding errors in shaping the canals.

*(M:mesial, D:distal, B: buccal, L:lingual)