Risk factors for lower border notching after bilateral mandibular sagittal ramus advancement: three-dimensional...

Area of Science:

• Oral and Maxillofacial Surgery
• Orthognathic Surgery
• 3D Imaging in Dentistry

Background:

• Bilateral sagittal split osteotomy (BSSO) is a common procedure for mandibular advancement.
• Mandibular lower border notching (MLBN) is a potential complication following BSSO.
• Identifying risk factors for MLBN is crucial for surgical planning and patient outcomes.

Purpose of the Study:

• To determine the incidence of mandibular lower border notching (MLBN) after bilateral sagittal split osteotomy (BSSO) mandibular advancement.
• To identify patient-specific and surgical factors associated with the development of MLBN.

Main Methods:

• Retrospective single-centre study of 113 patients undergoing BSSO.
• Analysis of pre-operative, immediate post-operative, and late post-operative cone beam computed tomography (CBCT) scans.
• Statistical analysis to identify risk factors for MLBN.

Main Results:

• Mandibular lower border notching (MLBN) was observed in 15.5% of operated sides.
• Advanced patient age at surgery (P=0.002) and the degree of mandibular advancement (P=0.008) were significant risk factors for MLBN.
• No association was found between MLBN and sex, operated side, third molar removal, or genioplasty.

Conclusions:

• Older patient age and the need for significant mandibular advancement are key risk factors for developing MLBN after BSSO.
• Surgeons should consider modified BSSO techniques or bone grafting to mitigate MLBN risk in susceptible patients.