Use of a modified maxillary relaxation-type occlusal splint in muscular-articular dysfunction of the temporomandibular joint

Background. Mechanical irritation of the oral cavity activates the mouth-opening reflex (mandibular depression). Uncoordinated muscle contraction during teeth clenching exerts traction on the articular disc, causing its displacement. Objective: to modify a maxillary relaxation-type occlusal splint for treating muscular-articular dysfunction of the temporomandibular joint. Materials and methods. Out of 325 examined individuals, 85 patients with muscular-articular dysfunction of the temporomandibular joint (63 women, 74 %; 22 men, 26 %; mean age of 36.2 ± 10.8 years) were randomly selected. They were divided into three groups according to the DC/TMD diagnostic criteria. The functional state of the masticatory muscles before and after treatment was assessed by electromyography. Results. The occlusal splint modified by us promotes relaxation of the masticatory muscles and a change in the stereotypical muscular guidance of the mandible into habitual occlusion, eliminating the influence of occlusion on condylar position and movement. Consequently, the condyles assume a new position independent of occlusal relationship. During jaw closure, the mandible shifts mesially without dental contact, providing physiological rest for the mandible, masticatory muscle relaxation, and suppression of the periodontomuscular reflex arc. Conclusions. Quantitative electromyography analysis showed that treatment with the modified occlusal splint improves muscle balance, restores coordination between working and balancing sides, and reduces pain in patients with muscular-articular dysfunction.