The effects of the resilient occlusal splint use in individuals with temporomandibular dysfunction clinical evaluation and electromyographic

Author(s)

Ana Maria Bettoni Rodrigues da Silva

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Ribeirão Preto (PCARP/BC)
• Defense date: 2009-04-30

Examining board members

Mathias Vitti; Claudia Maria de Felicio; Marcelo Oliveira Mazzetto; Helio Ferraz Porciuncula; Wilkens Aurélio Buarque e Silva

• Advisor: Mathias Vitti

Abstract

In order to understand better the physiopathology that affects the muscles of the stomatognathic system, an electromyography analyses has been included in the studies. The electromyography (EMG) allows us to check and evaluate the muscle efficiency, in both sides of the body (symmetry) and between the muscle pairs as a possible effect of the lateral jaw deviation (torque) (Ferrario et al., 1999, 2002). The aim of this work was to study, by surface EMG, the masseter muscles (superficial part) and temporal (back part) in both sides, as well as verifying the effect of the resilient occlusal splint use, as a devise for the temporomandibular disorder treatment (TMDs), and also compare it with the control group. We studied 23 individuals with TMD signs and symptoms, clinically evaluated, who received the resilient occlusal splint use treatment. We used the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) in order to establish the presence or the absence of TMD; also it was registered an EMG activity of the masseter and temporal muscles, in both sides, before, (initial Step 1), 30 days (Step 2) and after 60 days of the resilient occlusal splint use (Step 3) (Pettengill et al., 1998); and relate the electromyography findings with the occlusion and stomatognathic functions clinic evaluation; compare the results of a population with TMD and the control group of 23 individuals. The EMG evaluation was registered through chewing movements and the rest clinic conditions, as well as bilateral laterality with contact, protrusion and tooth clench. The statistic analysis was done with the SPSS software version 15.0 (Chicago, IL, USA). Due to the fact that the hypothesis of the majority of the variable normality was rejected (Shapiro-Wilks Test) non-parametric methods were used in the analysis. The level of significance adopted p ≤0,05. The control group data and the TMD were compared by the non-parametric of Mann-Whitney test, and the intra-group comparisons TMD (initial, 30 and 60 days of splint use) were done with the non-parametric Wilcoxon test. According to the results in the rest clinic condition, there was no significant statistic difference between the control groups and TMD. It was seen a significant difference intra-group of TMD. There was a significant difference on the right laterality comparing both control groups and TMD, and there was no significant statistic difference in the intra-group comparison. Therefore, on the left laterality, we didnt find any significant difference between the control groups and the TMD either on the intra-group TMD comparison. We could find a quite significant difference between the protrusion clinic condition, in the comparison between the control groups and TMD, in the TMD intra-group comparison. Regarding the teeth clenching with parafilm clinic condition, there was a difference between the control groups and the TMD, but there was no difference between the TMD intra-group. The chewing test with Bis and peanuts, we could see a TMD group. We could see on the Bis test that there was a difference between the control group and the TMD, and there was no difference between the TMD intra-group. For the chewing gum test and of the parafilm, we didnt noticed difference between the control group, in the TMD and in the TMD intra-group. This way, we can conclude that the electromyography activity of the masseter and temporal muscles of the TMD group decreased at the end of the treatment with the use of the occlusal splint in 60 days, considering the rest clinic conditions (except for the right masseter muscle), right and left laterality (for all muscles), and protrusion (except for the left masseter muscle). It was verified the same decrease for the teeth clenching with parafilm. (AU)