Relationship between neck disability and mandibular range of motion.

Background and Objective: There is a close interaction between the mandibular and cervical systems due to the existing neurological and biomechanical communications. This study aimed to evaluate the relationship between neck disability and mandibular range of motion (ROM).
Materials and Methods: Fifty-two women aged between 18 and 40 years were recruited and allocated to four groups using two outcome measures: the Neck Disability Index (NDI) and the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD): Group I (n=13), healthy volunteers; Group II (n=13), volunteers with TMD and neck disability; Group III (n=13), volunteers with TMD and without neck disability; and Group IV (n=13), volunteers with neck disability and without TMD. Mandibular ROM was evaluated as part of the RDC/TMD clinical examination. Statistical analysis involved one-way ANOVA followed by Tukey's test for comparisons between groups. Spearman's correlation coefficients were calculated to determined correlations among the variables.
Results: Significant differences were found in the mandibular ROM of functional opening in the comparisons between Groups I and III (p=0.009) and between Groups III and IV (p=0.024). No significant association was found between mandibular ROM and the NDI score (p > 0.05).
Conclusion: Based on the methodology employed, there is no association between mandibular ROM and neck disability in university women. In this sense, clinical interventions focusing on the flexibility of the temporomandibular joint does not have repercussions on the neck disability and vice versa.