Distance-dependent accuracy in Le Fort I maxillary repositioning procedures

Area of Science:

• Oral and Maxillofacial Surgery
• Orthognathic Surgery
• Biomedical Engineering

Background:

• Maxillary repositioning procedures aim for precise skeletal movements.
• The influence of repositioning distance on surgical accuracy remains under-investigated.

Purpose of the Study:

• To evaluate the correlation between planned maxillary repositioning distances and achieved accuracy.
• To identify planes and anatomical landmarks most affected by repositioning distance.

Main Methods:

• Analysis of Cone-beam CT scans from 92 patients undergoing Le Fort I osteotomies.
• Measurement of maxillary displacement in axial, sagittal, and transverse planes.
• Statistical analysis using Pearson's correlation coefficient to compare planned vs. achieved movements.

Main Results:

• Significant correlations between planned distance and achieved accuracy were found, particularly in the sagittal plane at the first molar landmarks (M1L and M1R).
• Accuracy decreased as the planned repositioning distance increased, with observed errors up to 12mm for planned movements of 0-4mm.
• The sagittal plane showed the weakest correlation, indicating greater potential for error in this dimension.

Conclusions:

• Surgical accuracy in wafer-based maxillary repositioning is distance-dependent.
• Longer repositioning distances are associated with reduced accuracy, especially in the sagittal plane and affecting molar regions.