Polysomnographic investigation of sleep and respiratory parameters in women with temporomandibular pain disorders.

STUDY OBJECTIVES: Temporomandibular pain disorders (TMD) and myofascial pain were linked to increased prevalence of insomnia and obstructive sleep apnea (OSA) on clinical grounds. However, the literature lacks an accurate polysomnographic (PSG) characterization of sleep abnormalities associated with TMD, given that prior studies included small or uncontrolled samples of TMD patients. The present investigation aims to objectively evaluate measures of sleep and respiratory disturbance in a large representative sample of TMD cases in comparison with matched controls. METHODS: Sleep, respiration, and limb movements were measured using a 2-night attended PSG protocol in 170 women-124 TMD cases with myofascial pain and 46 demographically matched controls. The second night data were compared between the groups using ANCOVAs. In TMD cases, the relationship between pain ratings and sleep parameters was analyzed using multiple regressions. RESULTS: In comparison to healthy controls, TMD cased evidenced a significant increase in stage N1 sleep (12.2% ± 7.6% vs. 9.2% ± 5.0%, p = 0.03), which was only mild relative to normative values. TMD cases also demonstrated mild but significant elevations in arousals associated with all types of respiratory events (6.0/h ± 6.1 vs. 3.5/h ± 3.3 p = 0.02) and in respiratory effort related arousals (RERAs, 4.3/h ± 4.3 vs. 2.6/h ± 2.7, p = 0.02). Myofascial pain predicted a lower sleep efficiency (p = 0.01), more frequent awakenings (p = 0.04), and higher RERA index (p = 0.04) among TMD cases. CONCLUSIONS: Myofascial pain in TMD is associated with mild elevation in sleep fragmentation and increased frequency of RERA events. Further research is required to evaluate the clinical significance of these findings.

Sleep bruxism and myofascial temporomandibular disorders: a laboratory-based polysomnographic investigation.

BACKGROUND: Many dentists believe that sleep bruxism (SB) is a pathogenic factor in myofascial temporomandibular disorder (TMD), but almost all supportive data rely on patients' self-reports rather than on direct observation. METHODS: The authors administered a structured self-report interview to determine whether a large and well-characterized sample of patients with myofascial TMD (124 women) experienced SB more often than did matched control participants (46 women). The authors then used data from a two-night laboratory-based polysomnographic (PSG) study to determine whether the case participants exhibited more SB than the control participants. RESULTS: The results of independent sample t tests and χ(2) analyses showed that, although self-reported rates of SB were significantly higher in case participants (55.3 percent) than in control participants (15.2 percent), PSG-based measures showed much lower and statistically similar rates of SB in the two groups (9.7 percent and 10.9 percent, respectively). Grinding noises were common in both case participants (59.7 percent) and control participants (78.3 percent). CONCLUSIONS: Most case participants did not exhibit SB, and the common belief that SB is a sufficient explanation for myofascial TMD should be abandoned. CLINICAL IMPLICATIONS: Although other reasons to consider treating SB may exist, misplaced concern about SB's sustaining or exacerbating a chronic myofascial TMD condition should not be used to justify SB treatment.