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Updated: Aug 18, 2026
In situ Compressive Loading and Correlative Noninvasive Imaging of the Bone-periodontal Ligament-tooth Fibrous Joint
Published on: March 7, 2014
Effective factors including periodontal ligament on vertical root fractures
Motoko Okitsu1, Hidekazu Takahashi, Takatomo Yoshioka
1Pulp Biology and Endodontics, Department of Restorative Sciences, Division of Oral Health Sciences Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. okitsu.endo@tmd.ac.jp
Abstract:
The purpose of the present study was to analyze effective factors including periodontal ligament on vertical root fractures (VRFs). Eighty maxillary central incisors were assigned to eight groups, depending on master apical file (MAF) size, loading point and existence of a simulated periodontal ligament (PDL). The gutta-percha in the root canal was vertically pressed with a Co-Cr rod using a universal testing machine. An ordinal logistic analysis was employed to determine significant factors. VRFs were observed in 88.8% of the specimens but no horizontal fractures were found. There were three types of VRFs: partial fracture not involving the apex (PF, 41.3%), partial fracture involving the apex (AF, 40.0%), and complete fracture (CF, 7.5%). MAF size significantly affected VRFs (p < 0.05); large MAF size exhibited more partial fractures involving the apex. Loading point and existence of PDL did not affect VRFs.
