Comparison of the Change in Condyle Position and Angulation in Skeletal Class III Two-surgery Cases between CAD/CAM Assisted and Conventional Orthognathic Surgery

Objective: To compare the change in condyle position and angulation in skeletal Class III two-jaw surgery cases between CAD/CAM surgery and conventional orthognathic surgery and between less setback and large setback of the distal segment of the mandible (criteria, 8 mm).

Patients and methods: The samples consisted of 48 skeletal Class III adult patients who underwent Le Fort I osteotomy and SSRO by a single surgeon. The subjects were divided into four groups according to surgery method [CAD/CAM surgery using surgical guides and customized titanium plates (FACEGIDE program, Megagen implant, Daegu, Korea) and conventional surgery] and setback amount of the distal segment of the mandible (criteria, 8 mm) [Group 1, CAD/CAM surgery, < 8 mm setback (n=8); Group 2, CAD/CAM surgery, > 8 mm setback (n=17); Group 3, conventional surgery, < 8 mm setback (n=16); and Group 4, conventional surgery, > 8 mm setback (n=7)]. ). Nine variables (Position of the condyle head: Axial condylar head. Sagittal condylar head, and Coronal condylar head; Position of the raums down:Axial ramus down, Sagittal ramus down, and Coronal ramus down; Angle of the condyle: Axial condylar axis angle, Sagittal condylar axis angle, and Coronal condylar axis angle) were measured to assess the changes in angle and distance of the proximal segment. Kruskal-Wallis test and Bonferroni correction were performed for statistical analysis.

Results: Condylar angle and ramus down in sagittal plane is significantly sable in Group B than in Group D

Conclusion: CAD/CAM assisted orthognathic surgery provides more accurate positioning of proximal segments than conventional orthognathic surgery