Abstract: The teaching of clinical maxillomandibular relationships is an area of weakness in dental school curricula. Most difficulties arise when a reference position is required to adjust or reconstitute the maximum intercuspation of the dentition. The dentist-derived concept of the centric maxillomandibular relation position is used to solve this problem. There is no consensus on the definition of this term. In the descriptions of clinical technique for recording the centric maxillomandibular relation position, clinical criteria to judge whether or not the position required has been achieved usually are not given. The dorsal border paths of the envelope of movement were used to develop a clinical criterion to identify the centric maxillomandibular relation position. Force or "guidance" is not used in this method. Test-patients with normal masticatory systems were randomly selected and fitted with a mechanical tracking apparatus. 50 undergraduate dental students and dental nurses were randomly selected and given instruction in the clinical technique to identify the centric maxillomandibular relation position. The ability of these students to identify the reference position was assessed by having them perform the technique blindfolded on the test-patients on whom tracking apparatus was fitted. Sixty eight percent of the test-clinicians succeeded in using the method to identify the reference position. There was no significant difference in the abilities of subgroups to use the method successfully, e.g., women compared to men, 2nd year students to 3rd year students. It was concluded that the method was a satisfactory way of learning how to identify the centric maxillomandibular relation position in a gentle, non-invasive fashion.

Abstract: This article describes the use of three devices that replace the wax rims in the registration of the intermaxillary position and of the vertical dimension of occlusion in completely edentulous patients who have been treated with Branemark implants. The devices consist of a mechanical “tooth” that can be adjusted in all three dimensions of space and of two plates that support the registration material. The mechanical tooth is connected to an abutment in the anterior region and a contact is established with a tooth in the opposite jaw at the vertical dimension in which the patient will be restored. This allows the operator to position the mandible in the centric relation in a condition of neuromuscular deprogramming and in the absence of posterior interferences. The two metal plates are then fixed to the posterior abutments, one on each side, and support the wax and zinc oxide eugenol paste used to register the intermaxillary position just established. (J Prosthet Dent 1998;80:249-52.)