Variation in centric relation in the conscious and the anesthetized patient

Every practitioner undertaking a case of dental rehabilitation has as one of the major goals of successful treatment making the patients’ centric occlusions coincide with their occlusion of maximum inter-cuspation in order to assure that their masticatory apparatus will function harmoniously. Specialists in dentofacial orthopedics, while always aiming at improving facial esthetics, enshrine the re-establishment of good masticatory functioning as an essential goal and to do this they must respect the fundamental principles of occlusion. Some serious skeletal deformities that cannot be completely resolved by dentofacial orthopedics alone require surgical intervention. These orthognathic procedures should be designed to achieve the same occlusal objectives of establishing skeletal and facial equilibrium with dentitions in normal Class I Angle occlusion and the condylar heads seated correctly in the mandibular fossas. This means that the orthodontist dealing with conscious patients and maxillo-facial surgeons operating on the same individuals when they are anesthetized will seek the same mandibulo-cranial relationship, the reference articulation, or centric relation. Because general anesthesia causes complete neural relaxation of the muscles that are an important element controlling centric relation surgeons need to know if it modifies this articular reference position. If it does, surgeons then have to know what, if any, adjustments they should make in response. In order to answer these questions we established an experimental protocol to compare the centric relation of the conscious patient (CR) to the centric relation of the same patient when anesthetized (CR 2).