A comparison of 3 methods of face-bow transfer recording: Implications fororthognathic surgery

Purpose: The purpose of this study was to compare the occlusal plane inclin ation of models mounted using 3 different systems for face-bow transfer wit h the actual occlusal plane inclination as measured on a cephalometric radi ograph. Patients and Methods: Twenty-two subjects were enrolled in this study. Thre e alginate impressions of the maxillary dentition were taken, and 3 stone d ental models were produced for each subject. Face-bow recordings were obtai ned on each subject using the SAM Anatomical Face-bow (Great Lakes Orthodon tics Products, Ltd, Tonawanda, NY), the Erickson Surgical Face-bow (Great L akes Orthodontics Products, Ltd) and a new technique developed by one of th e authors (J.G.). For each subject, the dental models were mounted on a SAM articulator using each of the 3 face-bow recordings. Finally, a lateral ce phalometric radiograph was obtained for each subject. The occlusal plane in clination was measured on the models and on the cephalometric radiographs. Differences among groups were tested using a 1-way analysis of variance. Bo nferroni test was used for post hoc comparison between different pairs of g roups. Results: The average occlusal plane inclination using the SAM Anatomical Fa ce-bow was 7.8 degrees +/- 4.2 degrees greater than the actual-a difference that was statistically significant. The mean occlusal plane inclination of the models obtained using the Erickson Surgical Face-bow was 4.4 degrees /- 2.2 degrees greater than the actual-a difference that was also statistic ally significant. The mean occlusal plane inclination of the models obtaine d by the new technique was only 0.9 degrees +/- 1.2 degrees greater than th e actual; this difference was not statistically significant. Conclusions: The new mounting technique is more accurate than the conventio nal SAM Face-bow or the Erickson Face-bow for reproducing the actual occlus al plane inclination. (C) 2001 American Association of Oral and Maxillofaci al Surgeons.