Comparison of amitriptyline with stabilization splint and placebo in chronic TMD patients: a pilot study

Trigeminal somatosensation in the temporomandibular joint and associated disorders

The temporomandibular joint (TMJ) consists of bone, cartilage, ligaments, and associated masticatory muscles and tendons that coordinate to enable mastication in mammals. The TMJ is innervated by the trigeminal nerve (CNV), containing axons of motor and somatosensory neurons. Somatosensation includes touch, temperature, proprioception, and pain that enables mammals to recognize and react to stimuli for survival. The somatosensory innervation of the TMJ remains poorly defined. Disorders of the TMJ (TMD) are of diverse etiology and presentation. Some known symptoms associated with TMD include facial, shoulder, or neck pain, jaw popping or clicking, headaches, toothaches, and tinnitus. Acute or chronic pain in TMD stems from the activation of somatosensory nociceptors. Treatment of TMD may involve over- the-counter and prescription medication, nonsurgical treatments, and surgical treatments. In many cases, treatment achieves only a temporary relief of symptoms including pain. We suggest that defining the sensory innervation of the temporomandibular joint and its associated tissues with a specific focus on the contribution of peripheral innervation to the development of chronic pain could provide insights into the origins of joint pain and facilitate the development of improved analgesics and treatments for TMD.

Synthesis of temporomandibular disorders management intervention outcomes for development of core outcome sets: A systematic review

INTRODUCTION

The selection of appropriate outcomes in clinical trials and systematic reviews is a crucial factor in determining the results that are useful, reliable, and relevant for both patients and healthcare professionals. Clinicians and researchers have been encouraged to develop and apply core outcome sets (COS) to minimise the discrepancy between studies.

AIM

This systematic review is the first phase of the COS development project for clinical trials in temporomandibular disorders (COS-TMD). It aims to identify and synthesise the outcomes used in the randomised controlled trials (RCT) that evaluated the effectiveness of interventions used in TMD management.

MATERIALS AND METHODS

An electronic search was performed in several databases: MEDLINE (via PubMed), Scopus, Web of Science, Cochrane Library and EMBASE. The eligibility criteria comprised RCT that applied any intervention to treat temporomandibular joint disorders or masticatory muscle disorders. The identified outcomes were categorised according to domains of the Initiative on Methods, Measurement and Pain Assessment in Clinical Trials (IMMPACT).

RESULTS

The electronic search resulted in 1606 studies. After removing duplicates and applying the eligibility criteria, 106 RCT were included. A total of 43 studies evaluated masticatory muscle disorders, 27 evaluated temporomandibular joint disorders, and 36 analysed mixed TMD.

CONCLUSIONS

The evaluation showed significant variability in the types of outcomes and their measurement instruments. In addition, some domains such as physical and emotional functioning, participant ratings of global improvement and adverse events have been neglected when determining the effectiveness of treatments for TMD.

The contribution of autonomic mechanisms to pain in temporomandibular disorders: A narrative review

BACKGROUND

Temporomandibular disorders (TMD) are diagnosed based on symptom presentation and, like other functional pain disorders, often lack definitive pathology. There is a strong association between elevated stress levels and the severity of TMD-related pain, which suggests that alterations in autonomic tone may contribute to this pain condition.

OBJECTIVES

This narrative review examines the association between altered autonomic function and pain in TMD.

METHODS

Relevant articles were identified by searching PubMed and through the reference list of those studies.

RESULTS

TMD sufferers report an increased incidence of orthostatic hypotension. As in other chronic musculoskeletal pain conditions, TMD is associated with increased sympathetic tone, diminished baroreceptor reflex sensitivity and decreased parasympathetic tone. It remains to be determined whether ongoing pain drives these autonomic changes and/or is exacerbated by them. To examine whether increased sympathetic tone contributes to TMD-related pain through β₂ adrenergic receptor activation, clinical trials with the beta blocker propranolol have been undertaken. Although evidence from small studies suggested propranolol reduced TMD-related pain, a larger clinical trial did not find a significant effect of propranolol treatment. This is consistent with human experimental pain studies that were unable to demonstrate an effect of β₂ adrenergic receptor activation or inhibition on masticatory muscle pain. In preclinical models of temporomandibular joint arthritis, β₂ adrenergic receptor activation appears to contribute to inflammation and nociception, whereas in masticatory muscle, α₁ adrenergic receptor activation has been found to induce mechanical sensitization. Some agents used to treat TMD, such as botulinum neurotoxin A, antidepressants and α₂ adrenergic receptor agonists, may interact with the autonomic nervous system as part of their analgesic mechanism.

CONCLUSION

Even if dysautonomia turns out to be a consequence rather than a causative factor of painful TMD, the study of its role has opened up a greater understanding of the pathogenesis of this condition.

Effects of therapeutic exercise and aerobic exercise programmes on pain, anxiety and oral health-related quality of life in patients with temporomandibular disorders

BACKGROUND

Pain and anxiety contribute to decreasing quality of life related to oral health in patients with temporomandibular disorders (TMD). Evidence-based practice has shown that therapeutic and aerobic exercise programmes are adequate strategies for modifying these factors.

OBJECTIVE

To assess the effects of aerobic exercise on pain, anxiety and quality of life related to oral health in patients with TMD.

METHODS

Forty-five patients diagnosed with TMD were divided into three groups of 15 participants: a therapeutic exercise programme (G1, mean 26.9 ± 5.5 years), a therapeutic and aerobic exercise programme (G2, mean 26 ± 4.4 years) and an aerobic exercise programme (G3, mean 24.9 ± 3.4 years). Pain intensity was assessed using a numerical rating scale (NRS), anxiety level and quality of life related to oral health through GAD-7 and OHIP-14, respectively. These parameters were evaluated twice at baseline (T0a/T0b), ending 8-week intervention period (T1) and 8-12 weeks after ending intervention (T2).

RESULTS

NRS significantly decreased in G1 (mean difference T0a/T1 = 5.2, p ˂ .001), G2 (mean difference T0a/T1 = 6.0, p ˂ .001) and G3 (mean difference T0a/T1 = 2.2, p = 0.001). OHIP-14 significantly decreased in G1 (mean difference T0a/T1 = 13.5, p ˂ .001) and G2 (mean difference T0a/T1 = 15.8, p ˂ 0.001) but not in G3 (mean difference T0a/T1 = 1.2, p = 0.55). There were no significant differences between groups regarding GAD-7. Between T1 and T2, there were no significant differences in variables.

CONCLUSION

Therapeutic exercises and therapeutic excercises combined with aerobic exercise groups had a significant decrease in pain and oral health-related quality of life at 8 and 12 weeks. These decreases were not seen for the aerobic exercise group.

Comparative Analysis of Web of Science and Pubmed Indexed Medical Journals Published in Former Yugoslav Countries

INTRODUCTION

The source of scientific information, methods for their evaluation, and methodology of their use are critical for serious scientific research and publishing of the scientific research results. Certain methodological principles should be inexcusably followed when designing clinical or observational research to avoid bias and presentation of results that do not reflect the truth about the phenomenon that is the object of the study.

AIM

The aim of this study was to compare the methodological quality of clinical trials and observational studies published in medical journals from ex-Yugoslav countries indexed in Web of Science (WoS) and Pubmed/MEDLINE.

METHODS

Clinical studies published in medical journals of ex-Yugoslav countries were retrieved from the WoS and Pubmed database, and the sample for analysis was randomly chosen from the retrieved publications. The rate of the most common errors in the design of clinical/observational studies was established by a careful reading of the sampled publications and their checking against predefined criteria.

RESULTS

Number and percent of the evaluated studies that failed to meet each of the methodological criteria tested, number of the evaluated criteria not satisfied per database and number of studies that satisfied more than 4 criteria were analyzed per database. When explanatory potential of journal impact factor, number of citations, time elapsed from publication and a database where a journal is referred were tested by linear regression in regard to the number of methodological criteria satisfied per study, the linear regression model was obtained by backward deletion method and achieved R2 adjusted of 0.166 (F=13.827, df1 = 2, df2 = 127, p=0.000). The methodological quality of studies was directly related to impact factor of the journals (B = 0.976, 95% confidence interval 0.539 - 1.413, p=0.000) and inversely with the database where a journal is referred (B =-0.444, 95% confidence interval-0.824 - -0.064, p = 0.022). Each additional unit of impact factor increased number of satisfied methodological criteria for about 1, while referring a journal only in WoS decreased number of satisfied criteria for 0.45 points in comparison with journals referred in both WoS and Pubmed/MEDLINE, and for 0.9 points in comparison to journals referred only in MEDLINE.

CONCLUSION

Methodological and scientometric quality of clinical studies published in medical journals from ex-Yugoslav region varies significantly, and the variations are higher in journals referenced only in WoS than in journals referenced in Pubmed/MEDLINE only, or in both Pubmed and Web of Science databases.

Long-term Effectiveness of Occlusal Splint Therapy Compared to Placebo in Patients with Chronic Temporomandibular Disorders

Purpose

The aim of this study was to compare long-term effectiveness of stabilization splint (SS) with that of placebo splint (PS) in chronic TMD patients and to investigate differences in treatment outcomes based on diagnostic subgroups [disc displacement (DD)/myofascial pain (MP)].

Materials and Methods

Thirty-four female participants, diagnosed with chronic TMD, were classified in groups: one provided with SS and other with PS and were followed for six months. Treatment outcomes included spontaneous pain [visual analogue scale (VAS)], self-perceived quality of life (OHIP-14), pain-free maximal mouth opening (MCO), maximal mouth opening (MMO), level of perceived stress (PSS), characteristic pain intensity [graded chronic pain scale (GCPS)], and functional jaw limitation [jaw functional limitation scale (JFLS)].

Results

Baseline characteristics did not differ significantly between the two groups (p>0.05). After six months of treatment the changes in spontaneous pain and OHIP-14 scores differed significantly between treatment groups (p=0.004, p=0.02 respectively), with greater reduction in SS compared to the PS group. Pain-free maximal mouth opening did not change significantly over time, however MCO values differed significantly between the two treatment groups, with greater overall values in the SS compared to the PS group (p= 0.046), as well as between TMD subgroups, with greater overall values in MP compared to DD patients (p= 0.03). In the SS group, significant difference in JFLS categories was found between baseline and after 6 months of treatment in all except emotional and verbal expression (mastication p=0.00015; vertical jaw mobility p=0.00018). No such changes in JFLS categories were observed in the PS group.

Conclusions

During 6-month period, SS was more effective than PS in reducing spontaneous pain and improving self-perceived quality of life and functional limitations of the lower jaw. Moreover, significantely higher values of pain-free mouth opening were observed in patients treated with stabilization splint. While placebo might be partly responsible for improving the symptoms of TMD, it seems that itcannot maintain a continual long-term positive therapeutic effect.

Which Treatment Is Effective for Bruxism: Occlusal Splints or Botulinum Toxin?

PURPOSE

The aim of the present study was to compare the efficacy of an occlusal splint and botulinum toxin for the treatment of bruxism.

PATIENTS AND METHODS

Seventy-three patients with myofascial pain due to bruxism were included in the present study. The patients were allocated into 3 groups. Group A was treated with an occlusal splint, group B was treated with botulinum toxin injections, and group C was treated with an occlusal splint and botulinum toxin injections. The Temporomandibular Disorder Pain Screener, Graded Chronic Pain Scale, Oral Behavior Checklist, Jaw Function Limitation Scale, and visual analog scale (VAS) by palpation of the chewing muscles were administered to all patients before treatment and 6 months after treatment.

RESULTS

The questionnaire and VAS scores decreased in all 3 groups (P < .0001). The VAS and questionnaire scores had decreased significantly in groups B and C compared with those in group A (mean VAS score: group A, 5 [range, 3 to 7]; group B, 1.9 ± 0.97; group C, 1.79 [range, 0 to 3]).

CONCLUSIONS

Occlusal splints might not be necessary for patients treated with botulinum toxin injections.

Placebo and nocebo response magnitude on temporomandibular disorder-related pain: A systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review (SR) was to answer the following question: "In adult patients with temporomandibular disorder (TMD)-related pain, what is the placebo or nocebo effect of different therapies?"

METHODS

A SR was performed with randomised clinical placebo-controlled trials on diagnosed painful TMD studies from five main databases and from three grey literature. Studies included must have sample older than 18 years, with painful TMD, which diagnosis was done by Research Diagnostic Criteria (RDC/TMD) or Diagnostic Criteria (DC/TMD).

RESULTS

Out of 770 articles obtained, 42 met the inclusion criteria for qualitative and 26 for quantitative analysis. Meta-analysis indicated mean variation on pain intensity for placebo therapy was higher on laser acupuncture with 45.5 mm point reduction, followed by avocado soya bean extract with 36 mm and amitriptyline 25 mg with 25.2 mm. Laser showed a 29% of placebo effect, as well medicine with 19% and other therapies with 26%. Possible nocebo effect of 8% pain increase was found for intra-articular injection of Ultracain.

CONCLUSIONS

Based on the available data, the placebo response could play a major effect on TMD pain management and may be responsible from 10% to 75% of pain relief. Laser acupuncture, avocado soya bean and amitriptyline promoted the higher placebo effect. Possible nocebo effect was found only for Ultracain injection with 8%.

CLINICAL RELEVANCE

Clinicians could apply such evidence to optimise pain management and judgement about treatment efficacy, and researches may find it useful when designing their investigations.