Automated Global Positioning Layout (GPL) for accuracy assessment in CAD-CAM mandibular reconstruction - Method...

Area of Science:

• Oral and Maxillofacial Surgery
• Medical Imaging
• Surgical Planning

Background:

• Standardized accuracy assessment is lacking in computer-assisted mandibular reconstruction.
• Current methods like landmark-based and surface-based comparisons have significant limitations, including operator variability and inability to detect local deviations.

Purpose of the Study:

• To validate a novel, automated protocol, the Global Positioning Layout (GPL), for quantifying 3D discrepancies in mandibular reconstruction.
• To compare the performance and reliability of GPL against existing Methods A (landmark-based) and B (surface-based).

Main Methods:

• Retrospective analysis of 17 patients undergoing mandibular reconstruction.
• Three operators performed measurements twice using GPL, Method A, and Method B.
• Performance metrics included reproducibility, operator variability, and spatial orientation of deviations.

Main Results:

• The Global Positioning Layout (GPL) method demonstrated complete reproducibility with no inter- or intra-operator variability.
• Landmark-based methods showed poor reproducibility, systematic bias, and frequent inapplicability.
• Surface-based methods were operator-dependent for alignment and masked localized deviations.

Conclusions:

• The Global Positioning Layout (GPL) is a robust, fully reproducible tool that overcomes critical limitations of current mandibular reconstruction accuracy assessment techniques.
• GPL provides a foundation for a standardized protocol to improve surgical outcome comparison, technique refinement, and patient results.