An investigation into the accuracy and validity of three points used in the assessment of autorotation in orthognathic surgery.
OBJECTIVE
To assess the accuracy and validity of three points used in the cephalometric assessment of autorotation in orthognathic surgery.


METHODS
A retrospective study of 15 cases of maxillary surgery.


METHODS
A postgraduate dental hospital in London.


METHODS
Fifteen well-documented cases of maxillary surgery with mandibular autorotation, treated by a single surgical, team were examined. Cephalometric surgical predictions were prepared, using the planned surgical movements, incorporating three different points advocated as centres of mandibular autorotation, for each case. These predictions were compared with the results achieved at surgery.


METHODS
The discrepancy between the predictions and the surgical result in each case was measured and subjected to statistical analysis. The method error was assessed and considered with the measured discrepancy.


RESULTS
Individual variation was seen, both between the individual landmarks and the individual cases studied. The discrepancies measured were broadly similar for each of the centres of autorotation. Statistical analysis failed to show any significant differences between the points studied.


CONCLUSIONS
All 3 points of autorotation examined will approximate mandibular autorotation following maxillary surgery and all can be considered equally valid.
Bryan
D C
DC
Queen Elizabeth Military Hospital, Woolwich, London.
D000704:Analysis of Variance; D002508:Cephalometry / Q000592:standards*; D003196:Computer Graphics; D006801:Humans; D008335:Mandibular Condyle; D008416:Mastoid; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D010043:Outcome and Process Assessment, Health Care; D010347:Patient Care Planning; D011237:Predictive Value of Tests; D011859:Radiography; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012399:Rotation