EC Dental Science

Introduction: BSSO is one of the most common surgeries performed in the correction of dentofacial deformities. This procedure is planned usually using OPG and lateral cephalogram. The mesio distal width of the ramus of the mandible is better visualised in all three dimensions in a CBCT. This study aims at studying the efficacy of CBCT especially in class 3 skeletal malocclusion patients and analysing if it is really a worthy addition to pre surgical planning.

Materials and Methods: 20 class 3 skeletal malocclusion patients posted for BSSO surgery were selected and CBCT of their mandibles were analysed in the mandibular ramus region and along the mandibular canal along with routine OPG and lateral cephalogram and the BSSO surgery was modified for each patient, taking into account the exact width of the ramus and the positioning of the mandibular canal of the particular patient.

Results: Of the 20 patients 7 had abnormally thin ramus. All the surgeries however went as planned and no intraoperative complications were faced.

Conclusion: CBCT is a valuable addition to pre surgical imaging and surgical planning especially in class 3 skeletal malocclusion cases with thin ramus undergoing SSO.

Keywords: CBCT; BSSO; Mandibular Prognathism; Ortho Gnathic Surgery; Surgical Planning; Mandibular Osteotomy; Ramus Assessment; Class 3 Malocclusion; Facial Asymmetry; Aesthetic Surgery

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