Abstract:
Objective: To evaluate the type and depth of lingual concavity in posterior mandible using pre-treatment CBCT (Cone
Beam Computed Tomography) images for dental implants.
Study Design and Setting: A cross-sectional study was designed and conducted on pre-treatment CBCT scans of 75
patients at Armed Forces Institute of Dentistry, Rawalpindi, Pakistan from February 2018 to November 2018.
Methodology: Pre-treatment CBCT scans of 75 patients were selected and following parameters were measured: type of
ridge (undercut, parallel, convex), ridge width, ridge height, depth of lingual concavity, concavity angle, and location of
the undercut. Data was analyzed using SPSS version .24. Post-stratification Mann-Whitney U test was used for effect
modifiers, while Kruskal-Wallis test was used to compare study parameters between groups. P value <0.05 was taken as
significant.
Results: A mean concavity depth of 1.17±1.40 mm was observed while majority (46.7%) of the CBCT images presented
with undercut type ridge. No significant difference was observed between males and females for any study parameter.
Conclusion: Undercut ridges were frequently observed, posing a threat of lingual perforation during implant placement.
Pre-operative assessment of implant site using CBCT can serve as a reliable method to avoid such complications
