Computer Assisted Surgical Simulation versus Model Surgery in Orthognathic Surgery: A Postoperative Comparison of Surgical Outcomes

Accuracy of virtual planning in orthognathic surgery: a systematic review

BACKGROUND

The elaboration of a precise pre-surgical plan is essential during surgical treatment of dentofacial deformities. The aim of this study was to evaluate the accuracy of computer-aided simulation compared with the actual surgical outcome, following orthognathic surgery reported in clinical trials.

METHODS

Our search was performed in PubMed, EMBASE, Cochrane Library and SciELO for articles published in the last decade. A total of 392 articles identified were assessed independently and in a blinded manner using eligibility criteria, out of which only twelve articles were selected for inclusion in our research. Data were presented using intra-class correlation coefficient, and linear and angular differences in three planes.

RESULTS

The comparison of the accuracy analyses of the examined method has shown an average translation (< 2 mm) in the maxilla and also in the mandible (in three planes). The accuracy values for pitch, yaw, and roll (°) were (< 2.75, < 1.7 and < 1.1) for the maxilla, respectively, and (< 2.75, < 1.8, < 1.1) for the mandible. Cone-beam computed tomography (CBCT) with intra-oral scans of the dental casts is the most used imaging protocols for virtual orthognathic planning. Furthermore, calculation of the linear and angular differences between the virtual plan and postoperative outcomes was the most frequented method used for accuracy assessment (10 out of 12 studies) and a difference less than 2 mm/° was considered acceptable and accurate. When comparing this technique with the classical planning, virtual planning appears to be more accurate, especially in terms of frontal symmetry.

CONCLUSION

Virtual planning seems to be an accurate and reproducible method for orthognathic treatment planning. However, more clinical trials are needed to clearly determine the accuracy and validation of the virtual planning in orthognathic surgery.

Computer-aided planning in orthognathic surgery-systematic review

The aim of this study was to conduct a systematic review to evaluate the accuracy and benefits of computer-aided planning in orthognathic surgery. The search was performed in PubMed, EMBASE, Cochrane Library, LILACS, and SciELO. The articles identified were assessed independently and in a blinded manner by two authors using selection criteria and eligibility criteria. The database search yielded 375 studies. Following the application of search and eligibility criteria, a final nine studies were included in the systematic review. The level of agreement between the authors in the study selection process was substantial (κ=0.767) and study eligibility was considered excellent (κ=0.863). The accuracy of translation was <1.2mm in the maxilla (vertical) and <1.1mm in the mandible (sagittal), and for rotation was <1.5° in the maxilla (pitch) and <1.8° in the mandible (pitch). Two studies showed a medium potential risk of bias and six studies showed a high potential risk of bias. Computer-aided planning in orthognathic surgery was considered accurate for the studies included in this systematic review. However, the low quality of these studies means that randomized clinical trials are needed to compare computer-aided planning to conventional planning in orthognathic surgery.