Incidence and prevalence of temporomandibular joint pain and dysfunction. A one-year prospective study of university students

Assessing Orofacial Pain Behaviors in Animal Models: A Review

Orofacial pain refers to pain occurring in the head and face, which is highly prevalent and represents a challenge to clinicians, but its underlying mechanisms are not fully understood, and more studies using animal models are urgently needed. Currently, there are different assessment methods for analyzing orofacial pain behaviors in animal models. In order to minimize the number of animals used and maximize animal welfare, selecting appropriate assessment methods can avoid repeated testing and improve the reliability and accuracy of research data. Here, we summarize different methods for assessing spontaneous pain, evoked pain, and relevant accompanying dysfunction, and discuss their advantages and disadvantages. While the behaviors of orofacial pain in rodents are not exactly equivalent to the symptoms displayed in patients with orofacial pain, animal models and pain behavioral assessments have advanced our understanding of the pathogenesis of such pain.

Arthrocentesis versus non-surgical intervention as initial treatment for temporomandibular joint arthralgia: a randomized controlled trial with long-term follow-up

Arthrocentesis for arthralgia of the temporomandibular joint (TMJ) is often only indicated when conservative, non-surgical interventions have failed. However, performing arthrocentesis as initial therapy may facilitate earlier and better recuperation of the joint. The aim of this study was to assess the efficacy of this therapy with a long-term follow-up. Eighty-four patients were randomly allocated to receive either arthrocentesis as initial treatment (n = 41) or non-surgical intervention (n = 43). Pain (100-mm visual analogue scale, VAS) and mandibular function impairment questionnaire scores (MFIQ, 0-100) were recorded at 3, 12, and 26 weeks, and ≥ 5 years (median 6.2, interquartile range 5.6-7.4 years). Univariable analyses were performed and linear mixed-effect models were constructed. Patients in the arthrocentesis group experienced significantly lower TMJ arthralgia compared to those treated non-surgically (pain during movement: -10.23 mm (95% confidence interval -17.86; -2.60); pain at rest: - 8.39 mm (95% confidence interval -13.70; -3.08)), while mandibular function remained similar in the two groups (MFIQ -2.41 (95% confidence interval -8.61; 3.78)). Of the final sample, 10 patients (10/39, 26%) in the non-surgical intervention group and two patients (2/34, 6%) in the arthrocentesis group received additional treatment during follow-up. Thus, initial treatment with arthrocentesis reduced TMJ arthralgia more efficaciously than non-surgical intervention in the long term, while maintaining similar mandibular function.

Orofacial pain disorders: An overview and diagnostic approach

Background:

Non-dental orofacial pain disorders are not uncommon, but idiopathic or primary facial pain syndromes are rare. Inadequate recognition of these disorders usually leads to unsatisfactory and unmet treatment needs.

Methods:

We conducted a narrative review with a literature search in PubMed until December 2021, focusing on current guidelines and the recently published International Classification of Orofacial Pain (ICOP).

Results:

In this paper, we provide an updated overview of the common orofacial pain disorders following the ICOP, covering the classification, epidemiology, pathophysiology, clinical approaches, and treatment options. Additionally, we propose a pragmatic approach focusing on the attack duration to improve distinguishing orofacial disorders.

Conclusion:

The introduction of ICOP offers the opportunity to better coordinate and concentrate scientific efforts, which lays the foundation for the identification of the disease mechanism of facial pain disorders and the optimization of the currently still insufficient therapeutic strategies.

Internet-based treatment for adolescents with symptomatic temporomandibular joint disc displacement with reduction. A randomized controlled clinical trial

OBJECTIVE

To evaluate treatment outcome of a jaw exercise (JE) intervention program combined with an information/counselling program (IC) vs. information/counselling alone.

MATERIALS AND METHODS

A clinical sample of 83 adolescents, experiencing painful clicking or catching/locking of the jaw, and diagnosed with symptomatic disc displacement with reduction according to RDC/TMD, were randomly assigned to JE/IC or IC program. Both programs were internet-delivered. The adolescents were examined clinically at baseline, at a 2-month mid-evaluation, and at 4months posttreatment by examiners blinded to which programs the adolescents were assigned to.

RESULTS

The JE/IC group showed significantly more improvements of painful catching/locking (p = .017), eating ability (p = .006) and of their jaw function limitation (p = .026) compared to the IC group. Significantly more adolescents in the JE/IC group also reported a ≥50% improvement of the catching/locking of the jaw with pain (p = .024) and for eating ability (p = .034) based on a severity index. Treatment method credibility and satisfaction were also significantly higher in the JE/IC group.

CONCLUSION

The internet-delivered JE/IC program showed a better outcome compared to IC alone. The former is thus a feasible and cost-effective treatment for adolescents with symptomatic disc displacement with reduction.

Interaction Between Awake and Sleep Bruxism Is Associated with Increased Presence of Painful Temporomandibular Disorder

AIMS

To explore whether awake and sleep bruxism interact in their associations with painful temporomandibular disorders (TMD) and whether the interaction is multiplicative or additive.

METHODS

In this case-control study, all participants (n = 705) were part of the multicenter Validation Project and were recruited as a convenience sample of community cases and controls and clinic cases. Logistic regression analyses were applied to test for the association between self-reported bruxism (sleep and/or awake) and the presence of painful TMD, and odds ratios (ORs) with 95% confidence intervals (95% CIs) were computed. Regression models included an interaction term to test for multiplicative interaction, and additive interaction was calculated as the relative excess risk due to interaction (RERI).

RESULTS

Based on logistic regression analyses adjusted for age and gender, the main effects for both awake (OR = 6.7; 95% CI: 3.4 to 12.9) and sleep (OR = 5.1; 95% CI: 3.1 to 8.3) bruxism were significant. While the multiplicative interaction (OR = 0.57; 95% CI: 0.24 to 1.4) was not significant, the results indicated a significant positive additive interaction (RERI = 8.6; 95% CI: 1.0 to 19.7) on the OR scale.

CONCLUSION

This study has demonstrated that awake and sleep bruxism are associated with an increased presence of painful TMD, and that both types of bruxism are not independently associated, but interact additively. As such, the presence of each factor amplifies the effect of the other.

Risk factors associated with incidence and persistence of frequent headaches

OBJECTIVE

Headaches represent a significant public health problem, but the knowledge of factors specifically related to incidence and persistence of headaches is still limited. The aim of this study was to evaluate whether gender, self-reported bruxism and variations in the dental occlusion contribute to onset and persistence of frequent headaches.

MATERIALS AND METHODS

The study population comprised 280 dental students, examined annually in a 2-year prospective study with a questionnaire and a clinical examination of the jaw function. In the analysis subjects were dichotomized into cases with frequent (once a week or more) or without frequent headaches (controls). The 2-year cumulative incidence was based on subjects without frequent headaches at baseline. Cases with 2-year persistent headaches reported such symptoms at all three examinations. Self-reported bruxism and factors in the dental occlusion at baseline were used as independent variables in logistic regression analyses.

RESULTS

The 2-year cumulative incidence of frequent headaches was 21%. Female gender (OR = 2.6; CI = 1.3-5.4), self-reported bruxism (OR = 2.3; CI = 1.2-4.4) and mandibular instability in intercuspal position (OR = 3.2; CI = 1.4-7.5) were associated with incidence of frequent headaches. Persistent headaches during the observation period were present in 12 individuals (4%) and significantly related to mandibular instability in intercuspal position (OR = 6.1; CI = 1.6-22.6).

CONCLUSIONS

The results indicate that female gender, self-reported bruxism and mandibular instability in intercuspal position are of importance in the development of frequent headaches. In management of these patients a multidisciplinary approach including dentists may be important and, thus, advocated.

The role of occlusal curvatures and maxillary arch dimensions in patients with signs and symptoms of temporomandibular disorders

OBJECTIVE

To identify differences in occlusal curvatures and maxillary arch dimensions between subjects with signs and symptoms of temporomandibular disorders TMDs and asymptomatic subjects.

MATERIALS AND METHODS

One hundred subjects 78 female and 22 male who consented to participate in this research were examined for signs and symptoms of TMDs according to the guidelines of the Research Diagnostic Criteria for Temporomandibular Disorders RDCTMD. In addition, occlusal measurements were performed for all subjects on plaster models. All statistical analyses were performed with SPSS version 19.

RESULTS

Significant associations were revealed between the depth of the curve of Spee COS and temporomandibular joint TMJ sounds. Furthermore, maxillary arch width was negatively correlated to the steepness of the curve of Wilson. No differences were found between subjects with and without a history of orthodontic treatment.

CONCLUSIONS

Subjects with TMJ sounds tend to have a flatter COS compared to subjects without TMJ sounds.

Prevalence of symptoms indicative of temporomandibular disorders in adults: cross-sectional epidemiological investigations covering two decades

OBJECTIVES

The aims were (1) to study possible secular trends in the prevalence of temporomandibular disorder (TMD) symptoms in adults and (2) to analyse possible associations between TMD symptoms and background factors.

MATERIALS AND METHODS

The investigation has a repeated cross-sectional design. Three independent, randomly selected samples of ∼100 individuals in the age groups of 20, 30, 40, 50, 60 and 70 years, a total of 1704 subjects, participated in the Jönköping studies in 1983, 1993 and 2003. All the subjects were evaluated using a questionnaire and a structured interview relating to the presence of TMD symptoms. Associations between symptoms and the Anamnestic Dysfunction Index (Ai) as dependent variables and each of the independent variables, age group, gender, reported bruxism, trauma (1983), self-perceived health impairment and the year of investigation were analysed in binary logistic regression models.

RESULTS

The prevalence of the separate symptoms, apart from for TMJ clicking, did not vary to any statistically significant degree between the different examination years. However, the prevalence of recurrent headache in 20-year-old subjects rose remarkably in 2003 and an increase in the Ai I and Ai II for the whole population was observed during the 20-year period. Reported bruxism, which increased during the study period, and self-perceived health impairment were associated with most of the TMD symptoms and the Ai.

CONCLUSIONS

An increase in the prevalence of TMD symptoms expressed as Anamnestic Dysfunction Index I and II has been noted over a 20-year period.

Risk factors associated with incidence and persistence of signs and symptoms of temporomandibular disorders

OBJECTIVE

To analyze whether gender, self-reported bruxism, and variations in dental occlusion predicted incidence and persistence of temporomandibular disorder (TMD) during a 2-year period.

MATERIAL AND METHODS

The study population comprised 280 dental students at Umeå University in Sweden. The study design was that of a case-control study within a 2-year prospective cohort. The investigation comprised a questionnaire and a clinical examination at enrolment and at 12 and 24 months. Cases (incidence) and controls (no incidence) were identified among those without signs and symptoms of TMD at the start of the study. Cases with 2-year persistence of signs and symptoms of TMD were those with such signs and symptoms at all three examinations. Clinical registrations of baseline variables were used as independent variables. Odds ratio estimates and 95% confidence intervals of the relative risks of being a case or control in relation to baseline registrations were calculated using logistic regression analyses.

RESULTS

The analyses revealed that self-reported bruxism and crossbite, respectively increased the risk of the 2-year cumulative incidence and duration of temporomandibular joint (TMJ) signs or symptoms. Female gender was related to an increased risk of developing and maintaining myofascial pain. Signs of mandibular instability increased the risk of maintained TMD signs and symptoms during the observation period.

CONCLUSION

This 2-year prospective observational study indicated that self-reported bruxism and variations in dental occlusion were linked to the incidence and persistence of TMJ signs and symptoms to a higher extent than to myofascial pain.

Temporomandibular disorders and migraine chronification

Among the established and potential comorbidities of migraine, the temporomandibular disorders (TMD) are rarely discussed, although they are of importance for several reasons. TMD may cause headaches per se, worsen existent primary headaches, and add to the burden of headache disorders. This article explores the potential comorbidity between migraine and TMD and the role of TMD as a potential factor to induce chronic migraine. We discuss the similarities between both conditions, review evidence to support the idea that both disorders are comorbid, and highlight the limited evidence suggesting that TMD influence migraine progression. Finally, we discuss the importance of cutaneous allodynia mediating the TMD/frequent headache relationship.

Modified condylotomy versus conventional conservative treatment in painful reciprocal clicking--a preliminary prospective study in eight patients

Modified condylotomy may be relevant in severe painful reciprocal clicking of the temporomandibular joint (TMJ) where conservative treatment is insufficient. The effect of the modified condylotomy was analyzed and compared with conventional nonsurgical treatment in a randomized pilot study of eight patients, 19-44 years of age, with severe painful reciprocal clicking. Before and after treatment, assessments were performed by subjective reports, clinical recordings, and blinded evaluations of radiography and magnetic resonance imaging (MRI). Based on the clinical evaluations before treatment, all conditions were disc displacements with reduction and arthralgia (Research diagnostic criteria for temporomandibular disorders), but based on MRI, one patient had disc displacement without reduction and another had normal disc position. The treatment effect was significantly better and the disorders were significantly more reduced with condylotomy than with conventional nonsurgical treatment (P < 0.05, Mann-Whitney U test). In the surgical group, the clicking and locking had disappeared, the pain during function was significantly reduced (P < 0.05, Friedman ANOVA), and in two patients the disc position was normalized. The clicking still persisted in the nonsurgical patients and the disc position was unchanged. Our conclusion is that modified condylotomy is a promising option to reduce symptoms and signs in severe painful reciprocal clicking.

Incidence and prevalence of myofascial pain in the jaw-face region. A one-year prospective study on dental students

OBJECTIVE

The aims of this study were to examine the 1-year period prevalence, incidence, and course of myofascial pain in the jaw-face region, and to analyze whether female gender, dental occlusion, and oral parafunctions have any influence on these signs and symptoms.

MATERIAL AND METHODS

The study population comprised 308 dental students examined at the start of their dentistry course and re-examined after 1 year. Case histories were collected using a questionnaire. The clinical examination included palpation sites of muscles, a submaximal clenching test, measurements of maximal mandibular mobility, and classification of morphological and functional dental occlusion.

RESULTS

The 1-year period prevalence of frequent myofascial symptoms was 19%. The incidence of myofascial pain, according to the Research Diagnostic Criteria for TemporoMandibular Disorders (RDC/TMD), was 4%. The female students presented an almost 4-fold incidence rate of myofascial symptoms compared to the male students. Non-symptomatic subjects were found predominantly among men, among those unaware of bruxism with bilateral contact in the retruded contact position (RCP), and among those with a stable intercuspal position (ICP). Variations in morphological occlusion did not show any relation to myofascial symptoms, nor did contact patterns in eccentric positions.

CONCLUSIONS

Female dental students were more prone to developing frequent myofascial pain and to perceiving local muscle soreness than were male students during a 1-year period. Both self-reported bruxism and registered mandibular instability in ICP showed association with the 1-year period prevalence of myofascial signs and symptoms in the jaw-face region.

Ocorrência de disfunção temporomandibular (DTM) e sua relação com hábitos orais deletérios em crianças do município de Monte Negro - RO

OBJETIVO: verificar a ocorrência de disfunção temporomandibular em crianças do município de Monte Negro/RO, correlacionando os achados à presença de hábitos orais deletérios. MÉTODOS: investigou-se a presença de quadros de disfunção temporomandibular, classificando-se em disfunção temporomandibular articular, muscular ou mista, bem como a presença de hábitos orais deletérios de sucção (mamadeira, chupeta e digital) e mastigação (onicofagia, morder objetos, morder a mucosa oral ou labial, bruxismo e apertamento dentário), em 79 crianças de seis a 11 anos (41 meninas e 38 meninos). RESULTADOS: dentre as 79 crianças investigadas, 27 (34,18%) apresentaram sinais de disfunção temporomandibular, sendo a disfunção articular a mais encontrada (48,15% n=13), seguida da mista (33,33%, n=9) e, com menor ocorrência, a muscular (18,52%, n=5 crianças). Hábitos orais deletérios foram encontrados em 69,62% (n=55) da amostra, sendo maior o número de crianças com hábitos de mastigação (39,91%, n=26) que de sucção (8,86%, n=7), observando-se casos em que os dois tipos de hábito estavam presentes (27,85%, n=22). Os resultados não demonstraram associação entre a presença de hábitos orais deletérios e disfunção temporomandibular (teste Qui-quadrado), independentemente do tipo de hábito. CONCLUSÃO: das crianças avaliadas, um terço (34%) apresentou sinais de disfunção temporomandibular, não havendo associação entre a disfunção temporomandibular com a presença de hábitos orais deletérios.