Correlation of condylar guidance using panoramic radiographic and protrusive interocclusal registration in edentulous patients an in vitro study

To evaluate the usefulness of panoramic radiograph by comparing the condylar guidance values obtained from interocclusal records and the panoramic radiographs in Edentulous subjects. Fifteen completely edentulous subjects aged between 45-65 years were selected for this study. In edentulous subjects, sagittal condylar guidance was determined by protrusive interocclusal record during jaw relation (gothic arch tracing) and try-in stage which were used to program the semi-adjustable articulator. Condylar guidance values on right and left side were determined. Panoramic radiographs taken of all the edentulous subjects in the natural head position aligned with the Frankfort horizontal plane (the line from the orbitale to porion) and tracings were done of the outline of glenoid fossa and the articular eminence. The angles formed by intersection of mean curvature line and Frankfurt horizontal plane were measured. Values so obtained were compared and statistically analysed by paired t-test and Karl Pearson's coefficient of correlation test. The condylar guidance values obtained from the interocclusal records were found to be less when compared to the values obtained from the panoramic radiographs. There is significant correlation for edentulous subjects (left r=.622 and right r=.719), during panoramic and interocclusal record. There is a positive correlation of horizontal condylar guidance angles obtained from the panoramic and interocclusal record methods in edentulous subjects. So, panoramic radiographs can be considered as a reliable aid to determine horizontal condylar guidance for programming of semi adjustable articulator.