An in vitro evaluation of the maxillary occlusal plane orientation obtained with an electronic application: A preliminary investigation.

STATEMENT OF PROBLEM: In the evaluation and fabrication of dental prostheses, maxillary occlusal plane orientation in the sagittal and coronal planes may affect functional and esthetic outcomes. The accuracy of a recently developed electronic application in transferring this orientation to a semiadjustable articulator has not been evaluated.

PURPOSE: The purpose of this in vitro study was to evaluate the coronal and sagittal orientation of the occlusal plane on maxillary casts mounted with an electronic application facebow system onto a corresponding semiadjustable arcon articulator.

MATERIAL AND METHODS: A maxillary typodont was placed into a phantom head (control) oriented with the Frankfort horizontal plane parallel to the horizon. A digital protractor was used to measure the angle between the occlusal plane of the maxillary arch of the phantom head and the Frankfort horizontal plane along the sagittal and coronal planes. The commercial system (test group) was used to make 15 facebow records of the maxillary typodont within the phantom head. The system records were used to mount diagnostic casts of the maxillary typodont onto a semiadjustable arcon articulator. The same measurements were made on the mounted diagnostic casts and were compared with the control. Statistical differences between the occlusal plane of the control and the occlusal plane of the mounted maxillary casts were determined using the 1-sample t test (α=.05).

RESULTS: The coronal orientation of the occlusal plane was significantly different (P<.001) between test group and control. No significant differences (P>.05) were found in the sagittal orientation of the occlusal plane.

CONCLUSIONS: Within the limitations of this study, variations in the coronal plane orientation were observed with the system. Variations in this plane may lead to adverse evaluation and clinical outcomes.