The functional state of the neck muscles with malocclusion

Abstract

The reasons for the high prevalence of chronic neck pain in patients with craniomandibular dysfunction are unclear, and the mechanisms of pathogenesis require in-depth clinical and theoretical study. The aim of the study was to analyze the bioelectrical activity of the neck muscles in the presence of centric and eccentric supracontacts of teeth.
Materials and methods.
The study carried out a digital analysis of occlusal relationships and surface electromyography of the neck muscles in two groups of patients aged 18 to 42 years with intact dentition. The first group (I) of persons without occlusal disorders, the second group (II) with the presence of centric and eccentric supracontacts of teeth.
Results.
Analysis of the time to reach maximum occlusion showed a significant increase in this indicator in the group II up to 0.279±0.037 sec relative to group I. In group II, there was an increase in the time of uncoupling during laterotrusion of the lower jaw up to 0.430±0.052 sec on the right and 0.492±0.063 sec on the left, which is significantly higher than in the group I. Analysis of the bioelectrical activity of the neck muscles showed significant differences in the amplitude coefficient of the area under the curve m. sternocleidomastoideus in the examined groups (p<0.05). The asymmetry is more pronounced in the group II, in contrast to the group I, with a maximum compression of 2.27 (1.39—3.21) and 1.10 (1.00—1.27), respectively, when grinding the test material 2, 36 (1.70—3.00) and 1.18 (1.06—1.23), respectively (p<0.05). Correlation analysis made it possible to determine the relationship between the presence of hyperbalancing supracontacts in group II and an increase in the asymmetry of contraction m. sternocleidomastoideus (r=0.74) and m. trapezium (r=0.68).
Conclusion.
Our study showed that the arising centric and eccentric supracontacts, caused by occlusal aberrations, lead to a different degree of disruption of the bioelectrical activity of the neck muscles, namely, to discoordination in the performance of a specific function. An in-depth analysis of these changes requires further fundamental and clinical research, followed by the development, formulation and implementation of new diagnostic and therapeutic approaches.