An article from Johns Hopkins School of Medicine evaluated TMD patients relative to sleep disorders and pain sensitivity. The study found two or more sleep disorders in 43% of patients. Insomnia and sleep bruxism were the two most commonly found sleep disorders. Both Primary Insomnias (PI) and Respiratory Disturbance Index (RDI) were associated with increased pain sensitivity.
The authors concluded Primary Insomnia and Sleep Apnea were at such high rates that any TMD patients complaining of sleep distubances should be rferred for polysomnography (sleep test). They also felt that Primary Insomnia was highly associate with hyperalgesia and may be linked to the onset of central sensitivity and be the underlying etiology in idiopathic pain disorders. The authors also stated "The association between sleep disordered breathing and hypoalgesia requires further study and may provide novel insight into the complex interactions between sleep and pain-regulatory processes."
The NHLBI has previously published a report "Cardiovascular and Sleep Related Consequences of Temporomandibular Disorders" Which details the numerous problems related to TMD problems. The majority of problems are related to sleep apnea (http://www.ihatecpap.com/sleep_apnea_dangers.html) and to disturbances in the trigeminal nervous system and the trigeminal vascular effects.
It is becoming more apparent that TMJ joint pain and headaches related to TMD are only the tip of the iceberg. Correction of the neuromuscular function of the stomatognathic system could lead to widespread improvements in health and function in sites often not associated with TMD problems. An excellent article on neuromuscular dentistry can be found in Sleep and Health Journal at http://www.sleepandhealth.com/neuromuscular-dentistry.
PubMed abstract below:
Sleep. 2009 Jun 1;32(6):779-90.
Sleep disorders and their association with laboratory pain sensitivity in temporomandibular joint disorder.
Smith MT, Wickwire EM, Grace EG, Edwards RR, Buenaver LF, Peterson S, Klick B, Haythornthwaite JA.
Johns Hopkins University School of Medicine, Department of Psychiatry and Behavioral Sciences, Baltimore, MD, USA. msmith62@jhmi.edu
STUDY OBJECTIVES: We characterized sleep disorder rates in temporomandibular joint disorder (TMD) and evaluated possible associations between sleep disorders and laboratory measures of pain sensitivity. DESIGN: Research diagnostic examinations were conducted, followed by two consecutive overnight polysomnographic studies with morning and evening assessments of pain threshold. SETTING: Orofacial pain clinic and inpatient sleep research facility. PARTICIPANTS: Fifty-three patients meeting research diagnostic criteria for myofascial TMD. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: We determined sleep disorder diagnostic rates and conducted algometric measures of pressure pain threshold on the masseter and forearm. Heat pain threshold was measured on the forearm; 75% met self-report criteria for sleep bruxism, but only 17% met PSG criteria for active sleep bruxism. Two or more sleep disorders were diagnosed in 43% of patients. Insomnia disorder (36%) and sleep apnea (28.4%) demonstrated the highest frequencies. Primary insomnia (PI) (26%) comprised the largest subcategory of insomnia. Even after controlling for multiple potential confounds, PI was associated with reduced mechanical and thermal pain thresholds at all sites (P < 0.05). Conversely, the respiratory disturbance index was associated with increased mechanical pain thresholds on the forearm (P < 0.05). CONCLUSIONS: High rates of PI and sleep apnea highlight the need to refer TMD patients complaining of sleep disturbance for polysomnographic evaluation. The association of PI and hyperalgesia at a nonorofacial site suggests that PI may be linked with central sensitivity and could play an etiologic role in idiopathic pain disorders. The association between sleep disordered breathing and hypoalgesia requires further study and may provide novel insight into the complex interactions between sleep and pain-regulatory processes.
PMID: 19544755 [PubMed - indexed for MEDLINE]
