Temporomandibular disorders and psychosocial status in osteogenesis imperfecta - a cross-sectional study.

BACKGROUND: Osteogenesis Imperfecta (OI) is characterized by a number of deviations in the orofacial region. The aims of the present study were to investigate the occurrence of temporomandibular disorders, to evaluate the psychosocial status, and to assess the dental occlusion in a population of adult OI patients. METHODS: Participants (n = 75) were classified with mild OI, type I (n = 56), or moderate-severe OI, type III and IV (n = 19). OI patients were examined according to the Research Diagnostic Criteria for Temporomandibular Disorders (axis I and II). RESULTS: Temporomandibular disorders and functional limitations in the orofacial region were rare and did not differ between patients with mild and moderate-severe OI (P > 0.050). No significant differences between Graded Chronic Pain Scale grades 0, 1, and 2 were found in mild OI vs. moderate-severe OI (P > 0.160). Few patients (16%) had signs of depression, but close to half (48%) had signs of somatization. Patients with moderate-severe OI had a lower mean number of teeth compared to patients with mild OI (P <  0.050). In general, malocclusions were prevalent, and mandibular overjet and posterior cross-bite were found more often in moderate-severe OI compared with mild (P <  0.050). CONCLUSIONS: Patients with moderate-severe OI had more malocclusions than patients with mild OI. The psychosocial status of OI patients was remarkably healthy considering the severity of this disabling systemic disorder. The bodily pain complaints frequently reported in OI patients were not largely reflected in the orofacial area as painful temporomandibular disorders.

Intramuscular pH modulates glutamate-evoked masseter muscle pain magnitude in humans.

BACKGROUND: This study was conducted to determine whether glutamate-evoked jaw muscle pain is modulated by the acidity and temperature of the solution injected. METHODS: Thirty two participants participated and received injections of high-temperature acidic (HT-A) glutamate (pH 4.8, 48 °C), high-temperature neutral (HT-N) glutamate (pH 7.0, 48 °C) and neutral temperature neutral (NT-N) glutamate (pH 7.0, 38 °C) solutions (0.5 mL) into the masseter muscle. Pain intensity was assessed with an electronic visual analogue scale (eVAS). Numerical rating scale (NRS) scores of unpleasantness and temperature perception, pain-drawing areas, mechanical sensitivity and pressure pain thresholds (PPT) were also measured. Participants filled out the McGill Pain Questionnaire (MPQ). One or two way ANOVAs were used for data analyses. RESULTS: Injection of HT-A glutamate solutions significantly increased the area under the VAS-time curve compared with injection of HT-N glutamate and NT-N glutamate solution (p < 0.040). The duration of glutamate-evoked pain was significantly longer when HT-A glutamate was injected than when NT-N glutamate was injected (p < 0.017). No significant effects of acidity were detected on pain drawings, NRS unpleasantness and heat perception, but there was a significant effect of acidity on MPQ scores and mechanical sensitivity. CONCLUSION: Acidity and temperature modulate glutamate-evoked jaw muscle pain suggesting an interaction between acid sensing and glutamate receptors which could be of importance for understanding clinical muscle pain conditions.

Effects of the Paced Auditory Serial Addition Task (PASAT) with different rates on autonomic nervous system responses and self-reported levels of stress.

To characterise self-reported levels of stress and autonomic responses in healthy humans evoked by different rates of the Paced Auditory Serial Addition Task (PASAT). Fifteen participants performed PASATs with different rates (3·6-, 2·4-, 1·6- or 1·2-s intervals) and a control task, in random order. Correct responses, self-reported levels of stress and autonomic responses to the PASATs were estimated. Increased PASAT rates were associated with decreases in correct responses (P < 0·001) and increases in self-reported levels of stress (P < 0·001). For autonomic responses, significant changes were seen in 10 variables during 2·4-s PASAT compared with the respective baseline; however, significant differences in relative changes from baseline were found between the 2·4-s PASAT and control task only for mean RR-intervals (P < 0·001), systolic and diastolic blood pressure (P = 0·002 and P = 0·006) and cardiac output (P < 0·001). Regarding comparison between the four PASATs, significant differences in the relative changes from baseline were seen between the 3·6-s PASAT and faster PASATs, for example mean RR-intervals, high-frequency power and respiration rate; however, there were no differences between the faster PASATs. The autonomic responses during the PASATs with different rates were quite similar for the faster PASATs (intervals < 2·4 s); however, the slowest 3·6-s PASAT evoked significantly less self-reported stress and autonomic arousal compared with the faster PASATs. Standardization of the PASAT rate may be important for studies on autonomic nervous system function and self-reported measures of stress. Future studies may test more complex interactions between stress, autonomic responses and pain responses.