Issues‎ > ‎Vol 7, issue 1‎ > ‎


Characterization of Mandibular First Molar Extraction Space for Dental Implant Placement Using CBCT Imaging – A Retrospective Analysis

Dler A. Khursheed *

*Department of Periodontics, College of Dentistry, Sulaimani University, Sulaimani, Iraq.

Submitted: 10/01/2020; Accepted: 24/01/2020; Published 01/06/2020



Objective: The aim of this study was to evaluate the consequences of untreated mandibular first molar extraction space on alveolar bone and adjacent teeth to suggest appropriate implant size selection and direction of its placement to achieve a favorable relationship between the prosthetic part, the implant fixture, and the adjacent teeth.          

Methods: This observational study evaluated 183 CBCT of mandibular first molar extraction spaces to measure adjacent teeth angulations, height, width, and length of interdental crestal bone. Besides interdental distance, unopposed teeth overeruption, and inferior alveolar nerve canal position were measured, and the continuous data have been subjected to the normality test to calculate the Mean and median of the variables.

Results: Mean molar-premolar, molar-bone crest, and premolar bone crest angles were 48.5±12.14◦, 46.4±11.9◦ , and 84.8±9.0◦ , respectively. Mean molar-premolar crestal bone lengths 11.66 ± 2.32 mm. The median bone width was 6.46 mm, and the median interdental distance was 7.54 mm. The mean alveolar crest to the roof of the inferior alveolar nerve canal was 16.42 ± 2.82 mm.

Conclusions: Untreated mandibular first molar extraction spaces significantly compromised interdental spaces and bone properties for proposing proper implant size, positions, and angulations.


Keywords: CBCT, Mandibular first molar, Extraction space, Dental implant.                                                                                                                                                                                             Full Article - PDF                                                                                                                                                                                                                                   


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