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A Postoperative Evaluation Guideline for Computer-Assisted Reconstruction of the Mandible
Published on: January 28, 2020
Anatomic study to determine a safe surgical reference point for mandibular ramus osteotomy.
Kyung-Ran Park1, Sang-Yoon Kim2, Gi-Jung Kim3
1Department of Oral and Maxillofacial Surgery, College of Dentistry, Yonsei University, Seoul, Republic of Korea.
Summary
A new surgical landmark, the midwaist point on the mandibular ramus, helps prevent inferior alveolar nerve injury during ramus osteotomy. This point aids surgeons in locating critical structures for safer procedures.
Area of Science:
- Oral and Maxillofacial Surgery
- Anatomy
- Neurosurgery
Background:
- Inferior alveolar nerve injury is a risk during mandibular ramus osteotomy.
- Accurate surgical landmarks are crucial for preventing nerve damage.
Purpose of the Study:
- To identify a reliable surgical reference point on the mandibular ramus.
- To prevent inferior alveolar nerve injury during ramus osteotomy.
Main Methods:
- Analysis of 125 3D computed tomography (CT) models of mandibles.
- Comparison of a newly defined 'midwaist point' with anatomical landmarks (antilingula, lingula, mandibular foramen).
- Inclusion of subjects with normal occlusion, mandibular retrognathism, and prognathism.
Main Results:
- The midwaist point showed consistent horizontal positioning relative to the lingula and mandibular foramen across all groups.
- Vertical positioning of the lingula and mandibular foramen relative to the midwaist point was highly variable.
- Distances from the midwaist point to the lingula and mandibular foramen were not significantly different among groups.
Conclusions:
- The midwaist point serves as an effective intraoperative reference.
- It assists surgeons in locating the lingula and mandibular foramen.
- This landmark helps mitigate the risk of inferior alveolar nerve injury.
