Endurance to physical strain in patients with temporomandibular disorders: a case-control study

Do intra-articular temporomandibular disorders show an association between physical bite function, self-perceived bite limitation and kinesiophobia? A case-control study

BACKGROUND

Little is known about the impact of intra-articular temporomandibular disorders (TMDs) on bite function, or how bite impairments in this subgroup relate to self-perceived bite limitation or kinesiophobia. This presents a challenge to practitioners involved in delivering care.

OBJECTIVES

To determine what bite impairments are associated with intra-articular TMDs, and explore how these impairments relate to self-perceived bite limitations and kinesiophobia.

DESIGN

Observational, case-control study.

METHOD

Sixty participants (n = 30 intra-articular TMDs, n = 30 healthy controls) were recruited via convenience sampling. Bite function was explored using pain-free bite force and bite endurance/steadiness (submaximal bite hold) measures. Self-perceived bite function and kinesiophobia were evaluated via the Patient specific functional scale (PSFS) and the Tampa Scale for kinesiophobia of Temporomandibular disorders (TSK-TMD) respectively. Between-group data were compared and associations between physical bite impairments, self-perceived bite limitation and kinesiophobia were explored in the intra-articular TMD group.

RESULTS

Pain-free bite force was significantly impaired in the intra-articular TMD group (-108N, p < 0.01, d = 0.9), and this impairment demonstrated moderate association with degree of kinesiophobia (p < 0.01, r = -0.4). No significant between-group difference was observed for bite endurance or force steadiness (p > 0.05). No association was observed between pain-free bite force and self-perceived bite limitation, or self-perceived bite limitation and kinesiophobia (p > 0.05).

CONCLUSIONS

Impaired pain-free bite force appears to be an important feature of intra-articular TMDs which should be considered within management. Kinesiophobia may be important to consider when assessing bite function in this subgroup. Future research is needed to guide optimal interventions and inform subsequent management guidelines.

The mouth-opening muscular performance in adults with and without temporomandibular disorders: A systematic review

Background

The mouth‐opening muscular performance in patients with temporomandibular disorders (TMDs) is unclear. Understanding the impairments of this muscle group within specific TMDs is important to develop proper management strategies.

Objective

To characterise the mouth‐opening muscular performance in adults with and without TMDs.

Methods

PubMed, EMBASE, CINAHL, Scopus, Web of Science and Cochrane databases were searched from inception to 12 November 2020. Bibliographies were searched for additional articles, including grey literature. Case‐control, cross‐sectional and interventional studies reporting mouth‐opening muscular strength and/or endurance were included. Risk of bias was assessed by the SIGN checklist for case‐control studies and by the NIH quality assessment tool for cross‐sectional studies. Results were pooled with a random‐effects model. Confidence in cumulative evidence was determined by means of the GRADE guidelines.

Results

Fourteen studies were included; most were rated as having a moderate risk of bias. Only three studies assessed patients with TMDs and the other 11 assessed healthy adults. Significant sex differences in muscular performance were found for healthy adults in the review (strength deficit for females versus males). There was a significant reduction in maximal mouth opening performance (strength and endurance) in the three studies that assessed patients with temporomandibular disorders.

Conclusion

Sex plays a significant role in maximal mouth opening strength. There is a lack of reliable data on the normal mouth‐opening strength and endurance of healthy adults as well as for patients with TMDs.

Implications

Lack of reliable TMDs patient data and comparable healthy adult data highlight future direction for research.

Jaw-neck motor strategy during jaw-opening with resistance load

BACKGROUND

The jaw and neck motor systems have a close functional integration but the effect of resistance load to the mandible during jaw opening on the jaw-neck integration is not known.

OBJECTIVES

To evaluate the effect of resistance load compared to no load on integrated jaw and neck motor function in individuals free from pain and dysfunction in the jaw and neck regions.

METHODS

Jaw and head movements during continuous jaw opening were recorded with an optoelectronic system (MacReflex^® ) in 26 pain-free individuals (14 women, 12 men, mean age 22 years). Jaw opening was performed with and without resistance load (1600 g) to the mandible. The relationship between jaw movement amplitude, head movement amplitude, head/jaw ratio (quotient of head and jaw movement amplitude) and resistance load were modelled using linear mixed-model analysis. A p-value <.05 was considered statistically significant.

RESULTS

The expected head/jaw ratio mean was increased by 0.05 (95% CI: 0.03, 0.08, p < .001) with resistance load as compared to no load. This corresponds to an increase in expected mean by 55.6%. With resistance load, expected mean head movement amplitude increased by 1.4 mm (95% CI: 0.2, 2.5, p = .018), and expected mean jaw movement amplitude decreased by 3.7 mm (95% CI: -7.0, -0.5, p = .025).

CONCLUSION

There is a compensation and adaptation of integrated jaw-neck motor function with an altered jaw-neck motor strategy during jaw opening with resistance load compared to no load. The head/jaw ratio demonstrates increased proportional involvement of the neck during increased load on the jaw system.

The feasibility of gym-based exercise therapy for patients with persistent neck pain

Background and aims Persistent neck pain is common and can be detrimental to the health of those who are affected. This is particularly common after neck trauma, where it poses a challenge to health care providers. In this paper, we present the design and results of a study aimed primarily at assessing the feasibility of a supervised exercise intervention for patients with persistent neck pain after trauma. As a secondary aim, we analyzed the results of the intervention. Methods We designed and conducted a feasibility study using a mixed methods design. Ten patients with persistent neck pain (nine with a history of neck trauma and one with sudden onset of neck pain) were recruited from a specialized pain rehabilitation center and underwent a gym-based individual exercise therapy intervention, supervised by a physical therapist. We assessed the feasibility of the exercise therapy intervention based on the experiences of the patients and physical therapists. We analyzed both quantitative and qualitative results using descriptive statistics, content analysis, and questionnaires. Results The study found the exercise therapy to be a feasible alternative for patients with persistent neck pain. Most of the practical aspects of the intervention and study were executed as planned, and the study was well received by the patients, who found it a valuable part of their rehabilitation. In the quantitative analysis, improvements were observed on the Neck Disability Index, numerical rating scale for pain, EuroQol 5D, and physical activity, with scores on the Neck Disability Index showing a statistically significant improvement. Scores on the Disability Rating Index showed a non-significant deterioration. The qualitative analysis uncovered one overarching theme and four themes for the patients and three themes for the physical therapist. Conclusions The exercise therapy intervention seems to be feasible with favorable outcomes for the patients. The quantitative and qualitative analyses demonstrated exercise therapy to be beneficial from several different perspectives. However, although structured, the training needs customization and individual adaption from a clinical reasoning perspective in order to meet each patient's individual needs. Implications This study shows that supervised gym-based exercise therapy is feasible for patients with severe, persistent neck pain. It facilitates and motivates the execution of a larger, controlled trial, which might then lead to a new and potentially effective addition to the toolbox of all health care providers treating patients with persistent neck pain.

Smiling, Yawning, Jaw Functional Limitations and Oral Behaviors With Respect to General Health Status in Patients With Temporomandibular Disorder-Myofascial Pain With Referral

Background: The temporomandibular joint is the one of the most important joints in the human body. It enables numerous orofacial functions such as mastication, swallowing, breathing, speech, emotional communication, and facial expressions. The aim of the study was to evaluate the prevalence of jaw functional limitations and oral behaviors with respect to general health status in patients with temporomandibular joint disorders—myofascial pain with referral.

Materials and methods: The study group consisted of 50 individuals (37 females and 13 males) with complete natural dentition. The average age was 23.36 years with ± 0.30 as a standard error. All subjects underwent clinical examination and were diagnosed with myofascial pain with referral according to the Diagnostic Criteria for Temporomandibular Disorders. The survey was conducted in connection with the Jaw Functional Limitation Scale-8 (JFLS-8), Jaw Functional Limitation Scale-20 (JFLS-20), Patient Health Questionnaire-4 (PHQ-4), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire-15 (PHQ-15), and Oral Behaviors Checklist (OBC).

Results: The most common functional problems in the entire study group were chewing tough food and yawning. In terms of gender, statistically significant differences were noted for chewing tough food and smiling (p = 0.015451; p = 0.035978, respectively). With respect to Bonferroni correction and Benjamini-Hochberg procedure, the observed differences were not statistically significant. There were no statistically considerable differences in mastication, mandibular mobility, verbal and emotional communication, or global limitations (p > 0.05). Over half (56%) of the respondents had depression of varying severity. Somatic symptoms of different severity were found in 78% of the patients, and 44% of the respondents declared anxiety disorders. The score of the Oral Behavior Checklist (OBC = 27.18) highlighted a high tendency for developing craniomandibular disorders.

Conclusion: Patients with myofascial pain with referral, demonstrated a disturbed biopsychosocial profile. The restrictions in yawning and smiling as well as limitations in mastication, mobility, verbal and emotional communication, and global limitations appear to be significant predictors of craniomandibular dysfunction. Depression, stress, and somatic disorders are important factors predisposing patients to the occurrence of myofascial pain with referral. The progression of oral behaviors may indicate the role of somatosensory amplification.

Association of Temporomandibular Disorder Symptoms with Physical Fitness among Finnish Conscripts

Studies on the role of physical fitness, physical activity and obesity as risk factors for temporomandibular disorders (TMD) are scarce. The aim of the present study was to evaluate the association of TMD symptoms with physical fitness, physical activity and body mass index (BMI) among Finnish conscripts. The study sample consisted of 8685 Finnish conscripts. Data on self-reported TMD symptoms were used as outcome variables. Physical activity (questionnaire), physical fitness (measured with physical tests: Cooper test, push-ups, sit-ups and standing long jump) and body mass index (BMI) were used as explanatory variables. The associations between TMD symptoms and explanatory variables were evaluated using Chi-squared test and logistic regression analysis. The prevalence of all TMD symptoms was significantly higher among those who exercised more rarely than weekly. Pain-related TMD symptoms were also significantly more frequent among those who were overweight (BMI ≥ 25). Poor push-up results and overweight (BMI ≥ 25) were significantly associated with jaw pain and TMJ pain at jaw rest. The present study showed that good physical fitness may be a protective factor against TMD pain. Dentists should also be prepared to motivate TMD patients to physical activity and regular exercise as part of the treatment.

Patients' experiences of supervised jaw-neck exercise among patients with localized TMD pain or TMD pain associated with generalized pain

Objective: To evaluate temporomandibular disorder (TMD) patients' experiences of a supervised jaw-neck exercise programme. Materials and methods: The study used a mixed method design. All patients were diagnosed with myalgia according to the Research Diagnostic Criteria for TMD and divided into local myalgia (n = 50; 38 women, mean age 43 yrs, SD 14), and myalgia with generalized pain (n = 28; 27 women, mean age 43 yrs, SD 13). Patients participated in a ten-session supervised exercise programme that included relaxation, coordination and resistance training of the jaw, neck and shoulders. After the 10 sessions an evaluation form was filled out including both open- and closed-ended questions. The quantitative analysis was based on closed-ended questions concerned experience, adaptation and side-effects from the exercise programme. The qualitative analysis was employing inductive content analysis of open-ended questions. Results: Patients reported similar positive overall experiences of exercise regardless of diagnosis, although more individuals in the general pain group experienced pain during training (57%) compared to the local pain group (26%; p = .015). Patients in both groups shared similar experiences and acknowledged the possibility to participate in an individualized and demanding exercise programme. They expressed feelings of being noticed, taken seriously and respectful care management to be key factors for successful treatment outcome. The exercise programme was acknowledged as a valuable part of treatment. Conclusion: The hypothesis generated was that individualized and gradually demanding exercise in the rehabilitation process of TMD stimulates self-efficacy and confidence in chronic TMD patients regardless of whether the pain was localized or combined with wide-spread pain.

The prevalence of oral stage dysphagia in adults presenting with temporomandibular disorders: a systematic review and meta-analysis

OBJECTIVE

Temporomandibular disorders (TMDs) are the most commonly experienced non-dental orofacial pain disorders, with pain and dysfunction potentially resulting in oral stage dysphagia (OD). However, limited research has been conducted on this condition, with potential negative effects on clinical practice. Therefore, the aim of this study was to determine the prevalence of OD in adults presenting with TMDs, diagnosed as per the Research Diagnostic Criteria for Temporomandibular Disorders or the Diagnostic Criteria for Temporomandibular Disorders protocols.

MATERIAL AND METHODS

A systematic review of the literature was completed. Nine electronic databases were searched from inception to January 2017, with no date/language restriction applied. Grey literature, conference proceedings, and reference lists were also searched. Studies presenting original data regarding OD prevalence in adults presenting with TMDs were included if they investigated impaired swallowing, mastication, masticatory pain or fatigue, or weight loss. Study eligibility and quality were assessed by two independent reviewers. Methodological quality was assessed using the Down's and Black tool.

RESULTS AND CONCLUSIONS

This search yielded 20 eligible studies. Swallowing itself was impaired in only 9.3% of patients with TMDs. A range of additional OD signs and symptoms were also commonly reported (e.g. masticatory pain (87.4%) and fatigue (62%)). Study limitations included the small number of studies which were eligible for inclusion. As signs and symptoms of OD are frequently reported by patients with TMDs, psychometrically robust prospective research is warranted to determine current and optimal management of this condition.

The effect of supervised exercise on localized TMD pain and TMD pain associated with generalized pain

OBJECTIVES

To evaluate the effect of a supervised exercise program in patients with localized/regional temporomandibular disorder (TMD) pain and with TMD associated with generalized pain.

MATERIAL AND METHODS

Consecutively referred patients with localized/regional TMD pain (n = 56; 46 women and 10 men, mean age 44 years) and TMD associated with generalized pain (n = 21; 21 women, mean age 41 years) participated. Patients underwent a 10-session structured supervised exercise program over 10-20 weeks that included relaxation, and coordination and resistance training of the jaw and neck/shoulders. The outcomes were jaw pain intensity on the Numerical Rating Scale, endurance time for jaw opening and protrusion against resistance and chewing, and effect of pain on daily activities.

RESULTS

After the exercise program, a reduction in jaw pain was reported by the local (p = .001) and general (p = .011) pain groups. There were no significant differences in jaw pain intensity between the groups, before (p = .062) or after treatment (p = .121). Endurance time increased for both groups for jaw opening/protrusion (both p < .001) and chewing (both p = .002). The effect of jaw pain on daily activities decreased after exercise compared to baseline for both the local (p < .001) and general (p = .008) pain groups.

CONCLUSIONS

Supervised exercise can reduce TMD pain and increase capacity in patients with TMD. The results suggest that activation of the jaw motor system with exercise has a positive effect in patients with localized/regional TMD pain and TMD associated with generalized pain.