Arbitrary versus exact mounting procedure during fabrication of intraoral splints: an exploratory randomised controlled clinical trial
The present study examined possible advantages of a kinematical determination of hinge axis points over arbitrary axis points in the fabrication of occlusal splints for CMD treatment. The single blinded prospective randomised trial was performed in a general dental practice. A total of 14 consecutive patients presenting for CMD treatment were considered for participation and declared informed consent, and 12 patients (average age about 40 years) eventually participated. These patients were randomly assigned to either fabrication method and were not informed about how their individual splint was constructed. Condylography, required for the kinematical hinge axis determination, was therefore performed in both groups. Patients were recalled after 1, 2, 4, 14 and 28 days, and splints were selectively ground in order to achieve full occlusal contact in 12 points. The required number of corrective grindings was recorded, as was the clinical course of the patients. Kinematical splint construction yielded the desired result – mandibular repositioning as reflected by the full number of occlusal contact points – faster and more completely than the employment of an arbitrary hinge axis, and substantially (about 50%) less corrective grinding was required. The difference was statistically significant despite the rather small sample size. Clinically, both methods appeared to be equally effective. The greater initial effort required by kinematical determination of the individual hinge axis seems to be at least partially outweighed by a lower amount of corrective grinding required achieving the desired splint effect. Which method has the superior cost-benefit ratio remains to be determined.