Radiological examination of the relationship between the pterygomaxillary junction and fracture pattern

Area of Science:

• Oral and Maxillofacial Surgery
• Orthognathic Surgery
• Surgical Anatomy

Background:

• Le Fort 1 (LF1) osteotomies are standard procedures for correcting midface deformities.
• Complete separation of the pterygomaxillary junction (PMJ) is essential for successful maxillary repositioning.
• Maintaining the integrity of the pterygoid plate during osteotomy is a critical surgical consideration.

Purpose of the Study:

• To investigate the relationship between anatomical characteristics of the PMJ and fracture patterns during LF1 osteotomy.
• To identify specific anatomical features that predispose to different types of PMJ separation during LF1 osteotomy.

Main Methods:

• Radiological assessment of pre- and post-operative cone-beam computed tomography (CBCT) scans from 41 patients (82 samples).
• Morphometric analysis of the pterygomaxillary fissure and pterygoid plate dimensions.
• Classification of pterygomaxillary separation into clean-cut, maxillary sinus, or pterygoid plate fracture types.

Main Results:

• A statistically significant difference in pterygoid process thickness and pterygomaxillary region thickness was observed between clean-type fractures and pterygoid plate fractures.
• Thinner anatomical structures in the PMJ region were associated with specific fracture patterns.

Conclusions:

• Anatomical variations at the PMJ can complicate separation, increasing the risk of unintended fractures.
• Low thickness of the PMJ is a risk factor for unwanted fractures during LF1 osteotomy.
• Surgical factors such as incorrect osteotome angle, excessive force, and surgeon inexperience can also lead to pterygoid plate fractures.