Correlation between severity of temporomandibular disorder and mandibular range of motion

The aim of the present study was to determine the association between the severity of temporomandibular disorder (TMD) and mandibular range of motion (ROM). For such, a cross-sectional study was carried out with a sample of 92 women from the university community. The Fonseca's anamnestic index (FAI) was used to determine the severity of TMD, as follows: without TMD (n = 23), mild TMD (n = 23), moderate TMD (n = 23), and severe TMD (n = 23). Mouth opening, lateral excursion and protrusion of the mandible were measured. Spearman's correlation coefficients were calculated to determine the association between the FAI and mandibular ROM. Comparisons among groups were performed using the Kruskal-Wallis test with Dunn's post hoc test. No significant associations were found between TMD severity based on the classification of the FAI and ROM of functional mouth opening (rs = -0.001, p = 0.987), maximum active mouth opening (rs = -0.023, p = 0.822), passive mouth opening (rs = -0.026, p = 0.803), left lateral excursion (rs = 0.125, p = 0.231), right lateral excursion (rs = 0.087, p = 0.406) or protrusion (rs = -0.148, p = 0.157). Moreover, no statistically significant differences among severity groups were found (p > 0.05). Based on the findings of the present study, the severity of signs and symptoms of TMD was not associated with mandibular range of motion.