Comparison Of Sagittal Condylar Angle Obtained Using Cone Beam Computed Tomography And Interocclusal Record Materials- An In Vivo Study

Abstract

The sagittal condylar guidance angle (SCCA) is calculated by the condyle and articular disc traversing the contour of the glenoid fossa and the articular eminence. The condylar path is controlled by the shape of the fossa, the attachments of the ligaments, the biting load during movement (muscular influence), and the amount of protrusion. The SCGA on an articulator is determined using protrusive records of the patient. Intraoral registrations may compromise accuracy because of dimensional instability of registration materials and it becomes difficult for the dentist to select an appropriate material. The use of cone beam computed tomography (CBCT) has recently become much more common, and when measuring the SCGA using CBCT, more reliable results can be expected. This study was designed to compare the SCGA obtained using CBCT and protrusive interocclusal record made using polyvinyl siloxane and aluwax. Thirty dentulous subjects were selected. SCGA was calculated using CBCT scans for each subject. Intraoral protrusive records were made using polyvinyl siloxane and aluwax bite registration materials at 6mm of protrusion. Records were used to program the articulator and variation in the SCCA was noted. No significant difference was observed between right and left mean values of SCGA in CBCT, polyvinyl siloxane and aluwax. Positive correlation was found between all the three groups; however, significant difference was found in the mean values of SCGA between CBCT and polyvinyl siloxane, CBCT and aluwax (P=0.0001). No significant difference was found in the mean values of SCGA between polyvinyl siloxane and aluwax (P=0.9254). CBCT gave higher mean SCGA values than those obtained using polyvinyl siloxane and aluwax on semi-adjustable articulator in dentulous subjects; whereas mean SCGA values were comparable between polyvinyl siloxane and aluwax. The right and left SCGA values were comparable in each method.