MASSETER AND TEMPORALIS SURFACE ELECTROMYOGRAPHY IN PATIENTS WEARING COMPLETE DENTURES COMPARING ANTERIOR AND POSTERIOR OCCLUSAL CONCEPTS -A PILOT-STUDY

The activity of jaw elevator muscles (masseter and anterior temporal m uscle) was studied by surface electromyography in 17 patients wearing complete dentures with anterior-canine guidance. Baseline electromyogr aphy was recorded with the dentures and compared to recordings obtaine d with two different splints adapted to the upper denture, one providi ng anterior guidance leading to immediate disclusion of the posterior teeth during any jaw movement, the other providing posterior guidance buccally on the working side and lingually on the non-working side (bi laterally balanced occlusion). Recordings were obtained during a seque nce of different jaw movements: postural position, maximal tooth conta ct in intercuspal position, protrusive movement of the mandible (under tooth contact) and during lateral excursions, also carried out under tooth contact. Muscle activity was not significantly different as reco rded with dentures only versus with the splints providing anterior gui dance. However, a significant increase in activity was observed with b ilaterally balanced occlusion. The results of this study in edentulous people are similar to those found in patients with natural teeth.