Comparative Evaluation of Bone Anatomy for Ramal Implant Placement and Proximity to the Inferior Alveolar Canal in Different Facial Divergence to Assess the Ideal Site of Placement: A Cone-Beam Computed Tomography Study

Overview

Journal Cureus

Specialty Biomedical Engineering

Date 2025 Mar 3

PMID 40027046

Authors

Aarohi Singh Rathor

Alap Shah

Bharvi Jani

Jhalak Vekariya

Manushi V Shah

Affiliations

Soon will be listed here.

Abstract

Objective The objective of this study is to determine the optimal location for placing the Ramal implant and assess the maximum transverse width of the ramal bone and the proximity of the implant to the inferior alveolar canal (IAC) through cone-beam computed tomography (CBCT) scans. Materials and methods The CBCT scans of 30 patients were utilized in this study and its proximity to the IAC at different vertical heights (3, 5, and 7 mm) and four angles of insertion (0°, 10°, 15°, and 20°). The maximum transverse width of the ramus and the proximity to the IAC from the site of insertion were measured at three different vertical levels. Another important factor that was evaluated is the proximity of the Ramal implant to the IAC. After measuring the Ramal width, a central point was identified on it. From this point, a perpendicular line was drawn, which was parallel to the occlusal plane. Considering this line as a reference, angulations of 0°, 10°, 15°, and 20° were measured. Results The maximum transverse ramal width was seen in the hypodivergent growth pattern, i.e., 15.69 ± 0.952 mm at 3 mm. The highest clearance from the IAC was seen at a 20° angle in the hypodivergent growth pattern, which was 6.46 ± 2.76 mm at 3 mm. Conclusion The ramus of the mandible can be a predictable site for implant placement provided the variations in the anatomical structures have been carefully analyzed. It can be concluded that the Ramal implants can be safely placed at a level 3-7 mm above the permanent mandibular first molar above the occlusal plane and at 10°-15° in the case of hypo-divergent and normodivergent growth patterns at 20° or more in the case of a hyper-divergent growth pattern.

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