Associação entre insuficiência de convergência ocular e disfunção temporomandibular: estudo transversal

Abstract

Introduction: Temporomandibular Dysfunction (TMD) is a complex and multifactorial condition, being the most common orofacial pain condition of non-dental origin, and taking into account that changes in the temporomandibular joint (TMJ) may be related to the cranio-cervico-mandibular knowing that the structures that give rise to the nerves that control extraocular movements (MEOs) have proximity to the structures that control the sensitive and motor parts of the face and, in turn, with the musculature of the eyeball, the following question arises : do individuals with TMD have insufficient eye convergence? Objective: The main objective of this study is to assess and identify whether there is an association between insufficient eye convergence and TMD and the secondary objective is to assess whether there is an association of pain with mandibular range of motion in the different degrees of TMD. Methodology: 138 individuals with TMD were included in the study (77.46% female, 22.10% male), with an average age of 26.51 ± 6.14 years and 46 individuals without TMD (28.2% male, 71.7% female) , with an average age of 25.52 ± 5.81 years. All were assessed using the Diagnostic Criteria for Researching Temporomandibular Disorders (RDC / TMD), Fonseca's Anamnesis Index (IAF), Numerical Pain Scale (END) and Mandibular Range of Movement (ADM) using Pachymetry. To assess and diagnose ocular convergence, the Convergence Test (CT) and the Eye Convergence Insufficiency Symptoms (CISS) questionnaire were applied. The univariate analysis of variance (ANOVA) with Bonferroni's test post hoc was used to compare age and mouth opening and that of Kruskal-Wallis with Dunn's test post hoc to check mouth opening and pain between groups after the abnormality of data be verified by the Shapiro Wilk test. The test of Chi-square was applied to assess the association between TMD subgroups according to the Fonseca Anamnesis Index, with gender and ocular convergence. The level of significance accepted was p <0.05. Results: It was possible to observe the prevalence of individuals with convergence for all groups: without TMD (91%), mild TMD (84.7%), moderate TMD (89%), severe TMD (67.3%). However, convergence cannot be modified with the degree of TMD, that is, according to the increase in the severity of TMD, there is no increase in inconvergent individuals (p <0.003). We also observed a predominance of the right side being inconvergent. Regarding pain, the averages of all levels of severity were statistically different in relation to the healthy group (p <0.01: Dunn’s post-hoc test). In addition, it was possible to observe that the mouth opening decreases significantly (p <0.01: Dunn’s test post hoc) according to severity. Conclusion: Based on the results of the present study, the prevalence of individuals with normal convergence is higher for all groups of TMD severity and for the group without TMD, that is, the convergence cannot be modified with the degree of TMD.