Analysis of Leaf Gauge technique with use of E.M.G.

Abstract

When upper and lower anteriors occlude with leaf gauge between them, the condylar head is impinged upon the anterior-superior aspect of the mandibular fossae via the central part of the anterior disk, which results in tension of anterior belly of temporalis and superior head of lateral pterygold muscle.
When occlusal registration is made with impression material on posteriors with leaf gauge placed on anteriors, superficial layers of masseter and medial pterygold muscle start contracting. Therefore electric discharge of superficial layers of masseterincrease in comparison with the level which is recorded when leaf gauge alone is present between upper and lower anteriors.
Comparison of the antero-posterior position of the mandible and the inter-cuspal position of the normal subject showed that the former exists 0.2mm posterior to the inter-cuspal position. (Fig.8) This corresponds well to the established knowledge. Therefore it is considered that a combined use of EM-II and K-6 with the leaf gauge technique is the optimal method of occlusal registration at present.