Dados do Trabalho

Título

Relationship between Down Syndrome, Orofacial Pain, Masticatory Muscles and Sleep Disorders

Introdução

Down syndrome (DS) is a genetic disorder caused by trisomy of chromosome 21 (HSA21), with a great variability in the penetrance level. This disorder is characterized by a complex set of pathologies and several clinical phenotypes, such as: muscle hypotonia, ligament hyperlaxity, sleep disorders, and others. Temporomandibular disorders have been evidenced in DS patients; however, rare studies were found in this target public.

Objetivo

To investigate the presence of orofacial pain in patients with Down syndrome (DS) and to compare their clinical findings with the masticatory muscle hypotonia (MMH) and sleep disorders.

Métodos

Twenty-three volunteers young and adults with Down Syndrome (DS), 10 women and 13 men were submitted to the Axis I of Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), to verify the presence of orofacial pain on the temporal and masseter muscles, bilaterally, and on the temporomandibular joint (TMJ). The MMH was identified from electromyographic records of the temporal and masseter muscles, bilaterally, in maximum voluntary clench (MVC) condition, and measurement of maximum bite force (MBF; kgf). The maximum mouth opening (MMO) was calculated. The sleep disorders, including obstructive sleep apnea (OSA), sleep bruxism index (SBI; events/h), and snoring index (SI; events/h), were evaluated through the polysomnography type II home sleep test. A descriptive analysis of findings was performed. Statistical analysis was done.

Resultados

Non-significant differences were verified between muscle and TMJ pains according to the sexes, however, the pain in the left masseter muscle was more frequent in men (69%) and in TMJ, the pain was more frequent in men (46%). The electromyographic records of the temporal and masseter muscles and MBF intensity were well reduced in both the genders, indicating MMH. The left masseter muscle was more affected, mainly in men. Both the genders showed increase of MMO. The severity of OSA, SB and SI was higher in men (38,5%, 54%, 27,65 events/h respectively).

Conclusões

The MMH was confirmed in all subjects with DS, leading to a ligament hyperextensibility of TMJ and, consequently, a large increase of the mouth opening amplitude, mainly in men. The pain, found in the masseter and temporal muscles and in the TMJ, may have interfered in the manifestation of the MMH, mitigating the muscle force mainly in some men. No correlation was found between the orofacial pain and sleep disorders.

Palavras-chave

Down syndrome. Facial pain. Masticatory muscle. Sleep wake disorder