Quantitative analysis of masseter and temporalis EMGs: a comparison of anterior guided versus balanced occlusal concepts in patients wearing complete dentures

Abstract

The lack of easily measurable, objective physiological activity parameters of the masseter and temporalis muscle during jaw movements in humans has led to the consideration to revise data of surface electromyographies (EMGs) by applying a computerized quantification method. The aim of this follow-up analysis was to get quantitative data out of EMG-records of an earlier study. These records were obtained with two different splints, splint 1 providing an anterior front-canine guidance and splint 2 providing bilateral balanced occlusion. Utilizing a computer aided integration method led to numeric results which statistically proves the prediction of the previous investigation. Applying the integration method, the EMG raw signal was transformed into area-values which enabled a statistical work up of the data. Wilcoxon test statistics shows a significant (P<0.05) lower muscle activity in patients wearing dentures providing anterior front-canine guidance compared to those with balanced occlusion. It is concluded that the neuromuscular activity of the elevator muscles is highly reproducible and that the neuromuscular function is similar in edentulous subjects to that found in people with natural teeth. Furthermore, the study statistically proves earlier visual data that all those subjects, whose muscle activities were observed with anterior guidance (splint 1) compared to bilateral balanced occlusion (splint 2) showed significantly lower values with regard to subjects wearing splint 2.

Use of bruxchecker in patients with different types of bruxism

“…These demarcations served as an idea to develop diagnostic methods for bruxism 8 . Bruxchecker is a simple and effective device that is used for determining the patterns of occlusal contacts performed at lateral grinding movements of the lower jaw performed by patients with bruxism and is used to diagnose this condition 9 . Using the bruxchecker, we can record the occlusal contact points and direction of grinding during nocturnal bruxism.…”

“…Bruxchecker (bruksoanalizator) predstavlјa jednostavnu i efektivnu spravu koja se koristi pri određivanju okluzalnih šema kontakata koje se izvode pri lateralnim kretnjama donje vilice i koje prave pacijenti sa bruksizmom, a služe za dijagnostikovanje bruksizma 8 . Pomoću bruksoanalizatora mogu da se evidentiraju okluzalne kontaktne tačke za vreme noćnog bruksizma 9 . Bruksoanalizator može isto tako da se koristi i kao indikator korelacije između stanja okluzije i pojave parodontalne bolesti i TMD-a 10 .…”

The masticatory organ and stress management

“…Because it was clear that tremendous occlusal forces were exerted by parafunctional bruxism activity, which very much depends upon the occlusion schemes [26][27][28][29], contemporary concepts of occlusion slowly shifted to concepts based on the parafunctions of masticatory organ, grinding and clenching [30]. Therefore, it must be considered that these loads contribute to many oral diseases [31,32]; that is, excessive loads cause periodontal breakdown in some cases, and hard tissue breakdown or temporomandibular disorders in other cases.…”

Established prosthodontic rules confirmed in natural adolescent occlusion

“…It has been reported that occlusions with anterior canine guidance allow less muscular activity and forces within the stomatognathic system during parafunction than occlusions with group function patterns and balanced occlusions [10][11][12][13][14][15][16][17][18][19]. For long-term success and stability it has been suggested that an occlusal concept be established which keeps the muscular activity of the patient at the lowest level and thereby prevents the stomatognathic system from dysfunction or possibly self-destruction [20,21].…”

“…For long-term success and stability it has been suggested that an occlusal concept be established which keeps the muscular activity of the patient at the lowest level and thereby prevents the stomatognathic system from dysfunction or possibly self-destruction [20,21]. These references suggest that this is best accomplished by an anterior protected articulation (mutually protected articulation; [2]), even for complete dentures [15,[22][23][24][25]. These studies suggest that it would be worthwhile to reevaluate previously accepted occlusal rules in order to establish whether occlusion with anterior protected articulation is the occlusal scheme of choice.…”