Research routes on improved sleep bruxism metrics: Toward a standardised approach.

A recent report from the European Sleep Research Society's task force "Beyond AHI" discussed an issue that has been a long-term subject of debate - what are the best metrics for obstructive sleep apnoea (OSA) diagnosis and treatment outcome assessments? In a similar way, sleep bruxism (SB) metrics have also been a recurrent issue for >30 years and there is still uncertainty in dentistry regarding their optimisation and clinical relevance. SB can occur alone or with comorbidities such as OSA, gastroesophageal reflux disorder, insomnia, headache, orofacial pain, periodic limb movement, rapid eye movement behaviour disorder, and sleep epilepsy. Classically, the diagnosis of SB is based on the patient's dental and medical history and clinical manifestations; electromyography is used in research and for complex cases. The emergence of new technologies, such as sensors and artificial intelligence, has opened new opportunities. The main objective of the present review is to stimulate the creation of a collaborative taskforce on SB metrics. Several examples are available in sleep medicine. The development of more homogenised metrics could improve the accuracy and refinement of SB assessment, while moving forward toward a personalised approach. It is time to develop SB metrics that are relevant to clinical outcomes and benefit patients who suffer from one or more possible negative consequences of SB.

Obesity, sedentarism and TMD-pain in adolescents.

BACKGROUND: Obesity is a chronic and prevalent disorder, affecting individuals of all age. Previous evidence suggests that it is associated with some types of chronic pain, especially musculoskeletal pain. In addition, sedentarism is also associated with an increase of the inflammatory factors and chronic pain. So, we conducted a cross-sectional study to evaluate the association between obesity, sedentarism and the presence of TMD-pain in adolescents. METHODS: Temporomandibular Disorders were classified according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Obesity was assessed by the body mass index (BMI), bioimpedance (BIA), skinfold (triceps and subscapular) and circumferences (arm and abdominal). The level of physical activity was rated according to the instrument adopted by the Brazilian National School Health Survey. Descriptive statistics, univariate logistic regression and odds ratios (OR) with 95% confidence intervals (CI) were used to study the associations of interest. RESULTS: The sample consisted of 690 individuals with a mean age of 12.7 (±0.76) years of whom 389 (56.4%) were girls. Of the total, 112 (16.2%) had TMD-pain, 110 (15.9%) were obese according to BMI, 74 (10.8%) according to BIA, and 127 (18.4%) following the skinfolds and circumferences assessments. There was no significant association between TMD-pain and obesity according to BMI (P = 0.95), BIA (P = 0.16), skinfold and circumference (P = 0.22), and neither with sedentarism (P = 0.94). CONCLUSION: Obesity and sedentarism were not associated with the presence of TMD-pain in adolescents.

Relationship of Psychological Factors to Temporomandibular Disorders in Children.

This study evaluated the incidence of TMDs and their relationship to psychological factors in children ages 6 to 12 years who sought dental treatment at the Ponta Grossa State University. Following ethics committee approval and informed consent, 75 children were included in the study. Exclusion criteria were craniofacial malformations, history of orthodontic treatment and maxillary fractures. TMD severity was classified, using the Fonseca anamnesis index questionnaire, as "no TMD" (control) and "mild," "moderate" and "severe." Parents completed the Child Behavior Checklist, which measures behavior problems and competencies. Data were analyzed using the Chi-square test (a=0.01). Regardless of gender, 40 children had internalizing problems (with TMD, n=32; without TMD, n=8). Children presenting internalizing problems and TMD were classified as having mild (n=23), moderate (n=8) and severe TMD (n=1). Thirty-one children interviewed had externalizing problems (with TMD, n=24; without TMD, n=7). Children presenting externalizing problems and TMD were classified as having mild (n=18), moderate (n=5) and severe TMD (n=1). In addition, 36 children had behavior problems (with TMD, n=26; without TMD, n=10), of whom 19 children had mild, 6 children had moderate and 1 child had severe TMD. Psychological problems were related to TMD in Brazilian children ages 6 to 12.

Treatment of comorbid migraine and temporomandibular disorders: a factorial, double-blind, randomized, placebo-controlled study.

AIMS: To investigate the effectiveness of single and concomitant treatment of migraine and temporomandibular disorders (TMD) in women with the comorbidity. METHODS: Eligible female patients met International Classification of Headache Disorders, second edition (ICHD-2) criteria for migraine with or without aura and the Research Diagnostic Criteria for myofascial TMD (Grade ll or lll). After a run-in period (30 days), women with both migraine and TMD were enrolled into a four-arm, double-blind, placebo-controlled, factorial study testing the separate and joint effects of a migraine treatment (propranolol 90 mg) and a TMD treatment (stabilization splint [SS]) in four groups of patients. The four treatment groups were propranolol and SS (n = 22); propranolol placebo and SS (n = 23); propranolol and non-occlusal splint (NOS) (n = 23); and propranolol placebo and NOS (n = 21). The primary endpoint for migraine was change in headache days from baseline to the third month, and the secondary endpoint was change in days with at least moderate headache in the same period. The TMD endpoints included pain threshold and mandibular vertical range of motion. Data were analyzed using analysis of variance (ANOVA, Dunn's post-hoc test) or Kruskal-Wallis test. RESULTS: For the primary endpoint, in intention-to-treat (ITT) analyses (n = 94), propranolol and SS were associated with a nonsignificant reduction in the number of headache days, relative to all other groups. For per-protocol (PP) Completer analyses (n = 89), differences in the number of headache days reached significance (P < .05). The propranolol and SS group was significantly superior to the other groups on all other headache endpoints and in disability, in both ITT and PP analyses. No significant differences among groups were seen for the TMD parameters. CONCLUSION: In women with TMD and migraine, migraine significantly improved only when both conditions were treated. The best treatment choice for TMD pain in women with migraine is yet to be defined.

How to investigate and treat: migraine in patients with temporomandibular disorders.

Migraine and temporomandibular disorders (TMD) are highly prevalent conditions that frequently coexist in the same patient. The relationship between migraine and TMD is complex. Migraineurs often have pain in the TMD area; TMD sufferers, in turn, often experience headaches in addition to the pain in the jaw. Finally, migraine and TMD are comorbid, and the final phenotype of patients with the comorbidity may represent the aggregated contribution of both. Herein we briefly discuss the clinical commonalities of migraine and TMD, and the differential diagnosis of these conditions with other causes of facial pain. We close by presenting our experience in the treatment of patients with the comorbidity.

Headache and symptoms of temporomandibular disorder: an epidemiological study.

OBJECTIVES: A population-based cross-sectional study was conducted to estimate the prevalence of migraine, episodic tension-type headaches (ETTH), and chronic daily headaches (CDH), as well as the presence of symptoms of temporomandibular disorders (TMD) in the adult population. BACKGROUND: The potential comorbidity of headache syndromes and TMD has been established mostly based on clinic-based studies. METHODS: A representative sample of 1230 inhabitants (51.5% women) was interviewed by a validated phone survey. TMD symptoms were assessed through 5 questions, as recommended by the American Academy of Orofacial Pain, in an attempt to classify possible TMD. Primary headaches were diagnosed based on the International Classification of Headache Disorders. RESULTS: When at least 1 TMD symptom was reported, any headache happened in 56.5% vs 31.9% (P < .0001) in those with no symptoms. For 2 symptoms, figures were 65.1% vs 36.3% (P < .0001); for 3 or more symptoms, the difference was even more pronounced: 72.8% vs 37.9%. (P < .0001). Taking individuals without headache as the reference, the prevalence of at least 1 TMD symptom was increased in ETTH (prevalence ratio = 1.48, 95% confidence interval = 1.20-1.79), migraine (2.10, 1.80-2.47) and CDH (2.41, 1.84-3.17). At least 2 TMD symptoms also happened more frequently in migraine (4.4, 3.0-6.3), CDH (3.4; 1.5-7.6), and ETTH (2.1; 1.3-3.2), relative to individuals with no headaches. Finally, 3 or more TMD symptoms were also more common in migraine (6.2; 3.8-10.2) than in no headaches. Differences were significant for ETTH (2.7 1.5-4.8), and were numerically but not significant for CDH (2.3; 0.66-8.04). CONCLUSION: Temporomandibular disorder symptoms are more common in migraine, ETTH, and CDH relative to individuals without headache. Magnitude of association is higher for migraine. Future studies should clarify the nature of the relationship.

Migraine is the most prevalent primary headache in individuals with temporomandibular disorders.

AIMS: To assess the prevalence of primary headaches (HA) in adults with temporomandibular disorders (TMD) who were assessed in a specialty orofacial pain clinic, as well as in controls without TMD. METHODS: The sample consisted of 158 individuals with TMD seen at a university-based specialty clinic, as well as 68 controls. The Research Diagnostic Criteria for TMD were used to diagnose the TMD patients. HAs were assessed using a structured interview and classified according to the Second Edition of the International Classification for Headache Disorders. Data were analyzed by chi-square tests with a significance level of 5% and odds ratio (OR) tests with a 95% confidence interval (CI). RESULTS: HAs occurred in 45.6% of the control group (30.9% had migraine and 14.7% had tension-type headache [TTH]) and in 85.5% of individuals with TMD. Among individuals with TMD, migraine was the most prevalent primary HA (55.3%), followed by TTH (30.2%); 14.5% had no HA. In contrast to controls, the odds ratio (OR) for HA in those with TMD was 7.05 (95% confidence interval [CI] = 3.65-13.61; P = .000), for migraine, the OR was 2.76 (95% CI = 1.50-5.06; P = .001), and for TTH, the OR was 2.51 (95% CI = 1.18-5.35; P = .014). Myofascial pain/arthralgia was the most common TMD diagnosis (53.2%). The presence of HA or specific HAs was not associated with the time since the onset of TMD (P = .714). However, migraine frequency was positively associated with TMD pain severity (P = .000). CONCLUSION: TMD was associated with increased primary HA prevalence rates. Migraine was the most common primary HA diagnosis in individuals with TMD.

Painful Temporomandibular Disorder Is Associated With Migraine in Adolescents: A Case-Control Study.

Some types of primary headaches and temporomandibular disorders (TMD) are comorbid in adults and highly prevalent in adolescents. Herein, we investigated the association of painful TMD with specific headache diagnoses (migraine, tension-type headache) and with headache frequency in adolescents. We also explored the association of headache diagnosis with the number of painful sites in the trigeminal area. Painful TMD was assessed using the Research Diagnostic Criteria for TMD. We conducted a case-control study of adolescents from 13 to 15 years old who were recruited among participants in a previous epidemiologic study conducted in Araraquara, SP, Brazil. Headaches were classified according to the second edition of the International Classification for Headache Disorders. Logistic, multinomial logistic and linear regression models were used to test associations. Of 149 individuals, 55.7% presented painful TMD. Adolescents with painful TMD (cases) were more likely to have migraine compared with those without TMD (controls; odds ratio = 3.0, 95% confidence interval = 1.47-6.19, P = .033). Significant differences were not observed for probable tension-type headache (P = .307) or tension-type headache (P = .834). Painful TMD was also associated with an increase in headache frequency (linear-by-linear association = 8.051; P = .005). Only migraine was associated with a greater number of painful sites on palpation in the trigeminal area (P = .001). Migraine and frequency of headache were associated with painful TMD in adolescents. PERSPECTIVE: Migraine and headache frequency were strongly associated with painful TMD in adolescents, and causality must be determined. For now, the presence of 1 condition should raise suspicion of the other and warrants collaboration between orofacial pain specialists and neurologists.

Musculoskeletal Disorders.

Temporomandibular disorder (TMD), a type of musculoskeletal pain, is a main cause of pain in the orofacial region. It involves the masticatory muscles, temporomandibular joints (TMJs), and associated structures. The most common signs and symptoms are pain, limited range of motion, and TMJ sounds. TMD is a highly prevalent condition with a multifactorial etiology. Management aims to reduce pain and to improve function using a combination of therapeutic options. Noninvasive techniques are the first option and should be indicated considering the needs of each individual, the clinical features, and the mechanisms involved.

Headache associated with temporomandibular disorders among young Brazilian adolescents.

OBJECTIVE: To verify whether headaches (HAs) are associated with temporomandibular disorders (TMD) in young Brazilian adolescents. METHODS: From a population sample, 3117 public school children (12 to 14 y) were randomly invited to participate in this study. TMD was assessed according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I, in addition to questions #3, #4, and #14 of Axis II history questionnaire. HAs were investigated with question #18 of RDC/TMD Axis II. Chronic TMD pain was considered as pain that has persisted for 6 months or more, as proposed by the International Association for the Study of Pain. The statistical analysis consisted of χ tests, odds ratio (OR), and logistic regression models, adopting a significance level of 5%. RESULTS: The sample included 1307 individuals (a response rate of 41.93%), and 56.8% (n=742) were girls. Overall, 330 adolescents (25.2%) were diagnosed with painful TMD and 595 (45.5%) presented with HAs. Individuals presenting with HAs were more likely to present painful TMD (OR=4.94; 95% confidence interval [CI], 3.73-6.54, P<0.001), especially combined muscle and joint painful TMD (OR=7.58; 95% CI, 4.77-12.05, P<0.001). HAs also increased the risk to a higher magnitude for chronic TMD pain (OR=6.12; 95% CI, 4.27-8.78, P<0.0001). All estimated ORs remained essentially unchanged after adjusting for sex. DISCUSSION: HAs were a potential risk factor for TMD in adolescents, and the risk was particularly higher for painful and chronic TMD. When HAs are present in young adolescents, a complete examination is strongly recommended with regard to the presence of painful TMD, and vice versa.

Temporomandibular disorders are differentially associated with headache diagnoses: a controlled study.

OBJECTIVES: Temporomandibular disorders (TMDs) are considered to be comorbid with headaches. Earlier population studies have suggested that TMD may also be a risk factor for migraine progression. If that is true, TMD should be associated with specific headache syndromes (eg, migraine and chronic migraine), but not with headaches overall. Accordingly, our aim was to explore the relationship between TMD subtypes and severity with primary headaches in a controlled clinical study. METHODS: The sample consisted of 300 individuals. TMDs were assessed using the Research Diagnostic Criteria for TMD, and primary headache was classified according to International Classification for Headache Disorders-2. Univariate and multivariate models assessed headache diagnoses and frequency as a function of the parameters of TMD. RESULTS: Relative to those without TMD, individuals with myofascial TMD were significantly more likely to have chronic daily headaches (CDHs) [relative risk (RR)=7.8; 95% confidence interval (CI), 3.1-19.6], migraine (RR=4.4; 95% CI, 1.7-11.7), and episodic tension-type headache (RR=4.4; 95% CI, 1.5-12.6). Grade of TMD pain was associated with increased odds of CDH (P<0.0001), migraine (P<0.0001), and episodic tension-type headache (P<0.05). TMD severity was also associated with headache frequency. In multivariate analyses, TMD was associated with migraine and CDH (P=0.001). Painful TMD (P=0.0034) and grade of TMD pain (P<0.001) were associated with headache frequency. DISCUSSION: TMD, TMD subtypes, and TMD severity are independently associated with specific headache syndromes and with headache frequency. This differential association suggests that the presence of central facilitation of nociceptive inputs may be of importance, as positive association was observed only when muscular TMD pain was involved.