Management of temporomandibular disorders: a rapid review of systematic reviews and guidelines

Condylar osseous changes following conservative therapies: A cone-beam computed tomography longitudinal study on adult patients with degenerative temporomandibular joint disease

This retrospective study aimed to comprehensively investigate the impact of non-surgical treatments on condylar osseous changes in adult patients with degenerative joint disease (DJD). Radiographic and clinical data were collected for analysis. Cone-beam computed tomography (CBCT) was used to diagnose DJD, including flattening, erosion, osteophytes, sclerosis and cysts. Condylar osseous changes were divided into three classifications: progression, stability and remission. Kaplan-Meier analyses were performed to evaluate progression-free probability. Hazard ratios (HRs) of overall and specific DJD progression were calculated with multivariate Cox analysis. Hyaluronic acid (HA) injection significantly reduced the progression-free probability (P = 0.0312). HRs of progression after stabilization splint (SS) treatment within one year, glucosamine treatment within six months and HA injection was 3.41 (95% CI: 1.70-6.84; P = 0.0005), 0.35 (95% CI: 0.14-0.86; P = 0.0226), and 1.84 (95% CI: 1.06-3.20; P = 0.0313), respectively. HRs of progression of flattening, erosion, osteophyte, and sclerosis adjusted for gender and age after HA injection were 2.77 (95% CI: 1.32-5.81; P = 0.0071), 2.12 (95% CI: 1.09-4.10; P = 0.0264), 3.38 (95% CI: 1.08-10.54; P = 0.0361) and 2.78 (95% CI: 1.02-7.52; P = 0.0447) respectively. HA injection and SS treatment were possible risk factors for TMJ deterioration, while glucosamine treatment was possible protective factor against TMJ deterioration.

Arthrocentesis versus conservative treatments for temporomandibular joint disorders: A systematic review with meta-analyses and trial sequential analyses

This systematic review aimed to evaluate the efficacy of arthrocentesis compared to conservative treatments for symptomatic temporomandibular joint disorders. A systematic search for randomized, prospective and retrospective controlled trials was undertaken in five electronic databases. Various patient outcomes and economic evaluations were analysed for short-term (<6 months), intermediate-term (6 months to 5 years) and long-term (≥5 years) follow-up periods. Primary meta-analyses were performed for randomized controlled trials using random-effects models. Arthrocentesis was superior to conservative treatments regarding pain reduction at short-term (MD 14.5 (95% CI 9.7; 19.4), k= 9 RCTs, n= 545 patients, I2= 48%, high quality of evidence) and intermediate-term follow-up (MD 14.2 (95% CI 7.3; 21.1), k=9 RCTs, n= 547 patients, I2= 81%, moderate quality of evidence). Furthermore, arthrocentesis was superior to conservative treatment regarding maximum mouth opening improvement at short-term (MD 2.4 mm (95% CI 0.8; 4.1), k= 8 RCTs, n= 472 patients, I2= 80%, moderate quality of evidence) and intermediate-term follow-up (MD 2.2 mm (95% CI 0.5; 3.9), k= 8 RCTs, n= 468 patients, I2= 75%, moderate quality of evidence). Trial sequential analysis supported the conclusions of all primary meta-analyses. Results were clinically relevant for pain improvement, but not for maximum mouth opening improvement. Results at long-term follow-up and for other study outcomes were either lacking or too heterogenous for meta-analysis, highlighting the need for more standardized, high-quality research.

Genetic evidence strengthens the connection between emotional disorders and TMD-related pain: A two-sample Mendelian randomization study

OBJECTIVES

This study aims to evaluate the genetic association between emotional disorders and TMD-related pain through two-sample Mendelian randomization analysis.

DESIGN

Single-nucleotide polymorphisms (SNPs) related to emotional disorders (worry, nerves, or depression) were selected from genome-wide association studies (GWAS) from UK Biobank consortia, and related these to SNPs from FinnGen consortia. The inverse-variance weighted (IVW) was used as the primary effect estimate between emotional disorders and TMD-related pain, and various methods were applied to test the reliability and stability of the results, namely MR-Egger and weighted median.

RESULTS

The Mendelian randomization analysis showed that there was a positive correlation between emotional disorders and TMD-related pain, including worry group (IVW odds ratio (OR) = 3.86, 95 % confidence interval (CI) = 1.67-8.91), nerves group (IVW OR = 11.20, 95 % CI=2.04-61.64) and depression group (IVW OR = 3.32, 95 % CI=1.24-8.90). MR-Egger intercept and MR-PRESSO global test did not suggest evidence of horizontal or directional pleiotropy. Cochran's Q test showed that there was no heterogeneity between instrumental variables.

CONCLUSIONS

This study provides genetic evidence that strengthens the connection between emotional disorders and TMD-related pain, which has important implications at the causal level as well as throughout the treatment process of TMD-related pain.

Temporomandibular joint disorders and associated factors in a Turkish pediatric population

OBJECTIVE

To explore the presence and severity of temporomandibular disorders (TMD) signs and symptoms in a Turkish pediatric population, as well as their relationship to parafunctional behaviors, bruxism, malocclusion, anxiety, and sociodemographic traits.

METHODS

A cross-sectional study was conducted with patients between the ages of 5-15. Demographic variables, TMD signs and symptoms, parafunctional habits, bruxism, and malocclusion were evaluated by clinical examination. Fonseca Anamnestic Index (FAI) was used to determine the presence and severity of TMD. State-Trait Anxiety Scale for Children (STAI-C) was used to evaluate the anxiety. Student t, Mann-Whitney U, chi-square tests, and logistic regression were used for statistical analysis.

RESULTS

One hundred sixty-two participants (85 girls, 77 boys) with a mean age of 10.03 ± 1.88 years were included. The frequency of the participants who reported signs/symptoms of TMD was 19.7% according to FAI scores. Logistic regression analysis with the associated factors showed a significant relationship between the presence of the signs/symptoms of TMD and parafunctional habits (OR 4.24, 95% CI 1.64-10.93), and the presence of signs/symptoms of anxiety (OR 1.09, 95% CI 1.02-1.16).

CONCLUSIONS

Children and adolescents who exhibit parafunctional behaviors and anxiety had a higher likelihood of having TMD signs/symptoms of varying degrees of severity.

A guide for temporomandibular joint surgery using a simple surgical classification - A narrative-style review

The aim of this narrative style review is to clarify the role of TMJ surgery in the management of specific TMJ disorders by introducing a simple and practical surgical classification. A decade ago, a new surgical classification was published which, like the Wilkes classification, included the five escalating degrees of joint pathology, but with more practical definitions and proposed surgical options for each of the disease categories. The classification begins with Category 1 - painful but otherwise structurally normal joints, which are largely managed nonsurgically. Categories 2 and 3 denote reducing and nonreducing disc displacement of the TMJ, respectively, with the former treated by TMJ arthrocentesis or level 1 arthroscopy and the latter best managed with disc repositioning or discopexy. Category 4 describes degenerative changes to the disc itself, where the disc cannot be salvaged and is thus removed with TMJ discectomy. Lastly, Category 5 refers to end-stage joint disease, where none of the joint components can be salvaged; both the disc and condylar head are sacrificed, and the TMJ is reconstructed with a prosthetic total joint replacement. In the decade since its publication, various studies have served to validate the usefulness of the TMJ surgical classification, and how it can be applied to better understand the role of TMJ surgery in everyday clinical practice.

Exercise therapy in postoperative patients with temporomandibular joint internal derangement: A systematic review

OBJECTIVE

Postoperative patients with temporomandibular joint internal derangement (ID) often have problems such as limited mouth opening and pain. Exercise therapy can be advantageous for improving the recovery of patients following surgery. However, there is continuing discussion on the precise aspects of the exercise program, including the optimal timing, length, intensity, and use of assistive equipment. Hence, this study aimed to incorporate pre-existing exercise treatment regimens and investigate their impact.

METHODS

Publications that detailed the clinical treatment of patients with temporomandibular joint ID who received postoperative exercise therapy interventions were included. Nine databases were searched until October 1st, 2023. The JBI critical appraisal tools were used to assess the methodological quality of the included studies.

RESULTS

Five studies were finally included for subsequent analysis; two were randomised controlled studies, and three were quasi-experimental. Exercises suitable for such patients encompass vertical, transverse, and horizontal stretching, among which vertical stretch can be divided into active and passive movements. The start time ranged from the first to the fifth week after surgery, with a duration of 1-6 months. Although the data in the studies could not be integrated and further analysed, preliminary results showed that maximum mouth opening and pain in patients improved significantly. The therapeutic effect of combining three exercise methods was best and was related to patient compliance.

CONCLUSION

Exercise therapy positively affects postoperative rehabilitation in patients with temporomandibular joint ID. It is proposed that targeted, comprehensive studies be conducted to provide a basis for designing more sophisticated exercise therapy regimens and further confirm its curative effect.

Effects of Hyaluronic Acid (HA) and Platelet-Rich Plasma (PRP) on Mandibular Mobility in Temporomandibular Joint Disorders: A Controlled Clinical Trial

Hyaluronic acid (HA) is a glycosaminoglycan composed of D-glucuronic acid and N-acetylglucosamine with an up-to-several-million-Daltons chain-length responsible for the lubricating properties of the temporomandibular joint (TMJ) synovial fluid. Arthritis results in the predominance of HA degradation over synthesis leading to temporomandibular disorders (TMDs). TMD injection treatments are divided into HA supplementation and platelet-rich plasma (PRP) inflammation suppression. We questioned whether either approach lubricated the TMJ better and answered it in a two-arm equal-allocation trial with a non-concurrent active treatment control (two groups of 39 patients each). HA statistically significantly improved (p < 0.01) and PRP did not statistically significantly change (0.06 ≤ p ≤ 0.53) articular mobility compared to baselines in 128 TMJs. Statistically significant inter-group discrepancies were observed for abduction (MD = -4.05 mm; SE = 1.08; p = 0.00; d = -0.85) and protrusion (MD = -0.97 mm; SE = 0.43; p = 0.03; d = -0.51) but not for rightward (MD = -0.21; SE = 0.43; p = 0.63; d = -0.11) and leftward (MD = -0.30; SE = 0.42; p = 0.47; d = -0.16) movements. HA supplementation proved superior to PRP autografting in ad hoc TMJ lubrication and hence is more appropriate in hypomobile TMD cases of symptomatic treatment.

Arthrocentesis for temporomandibular joint disorders: a network meta-analysis of randomised controlled trials

OBJECTIVE

Clinical studies have demonstrated the effectiveness of arthrocentesis in managing temporomandibular joint disorders (TMDs). However, there is a lack of consensus among these studies regarding the selection of injectables. Furthermore, an increasing number of drugs have been tested for TMDs in recent years, complicating the decision-making process for clinicians. This study conducted a network meta-analysis of randomized controlled trials (RCTs) to compare the clinical efficacy of different arthrocentesis treatment regimens.

METHODS

We conducted a comprehensive search of Embase, PubMed, Cochrane Library, and Web of Science to gather articles on RCTs pertaining to the management of TMDs using arthrocentesis. This search spanned from inception of these databases up to July 29, 2024. We then performed a network meta-analysis using Stata 17.0 software. The outcome indicators used were VAS scores and changes in unassisted maximum opening. To determine the efficacy of each regimen, we employed surface-under the cumulative ranking curve (SUCRA) ranking.

RESULT

Forty RCTs were included, encompassing 1904 temporomandibular joints (TMJs) cases. Treatment options encompass platelet-rich plasma (PRP), hyaluronic acid (HA), corticosteroids (CS), bone marrow concentrate (BMAC), injectable platelet-rich fibrin (i-PRF), concentrated growth factor (CGF), Tenoxicam (TX), microfragmented adipose tissue (FAT), and their combination regimens. The SUCRA ranking revealed that the most effective treatment options at 1-, 3-, and 6-months post-arthrocentesis were HA + PRP, i-PRF, and BMAC, respectively.

CONCLUSION

HA + PRP, i-PRF and BMAC may represent the optimal arthrocentesis agents for the management of TMDs symptoms and restoration of TMJ function in the short, medium, and long term, respectively.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/ , identifier CRD42024563975.

Effects of adding electro-massage to manual therapy for the treatment of individuals with myofascial temporomandibular pain: a randomized controlled trial

OBJECTIVE

To evaluate the effect of the addition of dynamic cervical electrical stimulation (electro-massage, ES) to manual therapy (MT), compared to MT by itself, in individuals with myofascial temporomandibular pain.

METHODOLOGY

A total of 46 participants with bilateral myofascial temporomandibular pain for at least three months were distributed into two groups. Group 1 (n=21) received local MT consisting of soft tissue mobilization and release techniques over the neck and temporomandibular regions. Group 2 (n=25) received an ES procedure in the cervical region combined with the same intervention as group 1. All participants underwent a 2-week protocol. The primary outcomes were pain intensity (Visual Analogue Scale), pressure pain threshold (PPT) at the masseter and upper trapezius muscles (algometer), and pain-free vertical mouth opening (manual gauge). The secondary outcome was active cervical range-of-movement. Measurements were taken at baseline, immediately after intervention, and at a 4-week follow-up.

RESULTS

The ANOVA revealed significant changes over group*time, with better results for group 2 (large effect sizes) regarding pain intensity (p< 0.001; η2>0.14), pressure pain sensitivity and mouth opening (p<0.001; η2>0.14). Similar findings were observed for active cervical range-of-movement in all directions (p<0.001; η2>0.14), except rotation (p≥0.05).

CONCLUSION

Electrical stimulation therapy over the cervical region combined with a MT protocol over the neck and temporomandibular joint shows better clinical benefits than MT by itself in subjects with myofascial temporomandibular pain. Registration code: NCT04098952.

Abstracts of randomized controlled trials in splint therapy for temporomandibular disorders: Reporting quality and spin

BACKGROUND

Poor reporting quality and spin in randomized controlled trial (RCT) abstracts can lead to misinterpretation and distorted interpretation of results.

OBJECTIVES

This methodological study aimed to assess the reporting quality and spin among RCT abstracts on splint therapy for temporomandibular disorders (TMD) and explore the association between spin and potentially related factors.

METHODS

The authors searched PubMed for RCTs on splint therapy for TMD. The reporting quality of each abstract was assessed using the original 16-item CONSORT for abstracts checklist. The authors evaluated the presence and characteristics of spin only in abstracts with nonsignificant primary outcomes according to pre-determined spin strategies. Logistic regression analyses were performed to identify factors associated with the presence of spin.

RESULTS

A total of 148 abstracts were included in the reporting quality evaluation. The mean overall CONSORT score (OCS) was 5.86 (score range: 0-16). Only interventions, objectives and conclusions were adequately reported. Of the 61 RCT abstracts included for spin analysis, spin was identified in 38 abstracts (62.3%), among which 32 abstracts (52.3%) had spin in the Results section and 21 (34.4%) had spin in the Conclusions section. A significantly lower presence of spin was found in studies with exact p-value reporting (OR: 0.170; 95% CI: 0.032-0.887; p = .036) and a two-arm comparison design (OR: 11.777; 95% CI: 2.171-63.877; p = .004).

CONCLUSIONS

The reporting quality of RCT abstracts on splint therapy for TMD is suboptimal and the prevalence of spin is high. More awareness and joint efforts are needed to improve reporting quality and minimize spin.

Evaluation of the efficacy and quality of life in patients with temporomandibular joint disorders treated with Kovacs digital occlusal splint: a pilot study

BACKGROUND

Few studies have been conducted on treating temporomandibular disorders (TMDs) with new digital occlusal splints, which has increasingly attracted wide attention.

METHODS

To evaluate the clinical efficacy and quality of life (QoL) of Kovacs digital occlusal splint (KDOS) treatment in patients with TMD.

MATERIALS AND METHODS

Eighty-nine patients with TMD who were treated using KDOS were analyzed. The patients were divided into three groups according to the Wilkes stage. The clinical symptoms and QoL scores of the patients in each group were recorded before and at least three months after treatment, and the data were statistically analyzed and compared. The relationships between the disease severity, sex, age, and level of QoL before treatment and improvement in the clinical symptoms were analyzed using binary logistic regression.

RESULTS

The mean age and follow-up period of the patients were 28.0 ± 10.4 years and 4.9 ± 2.1 months, respectively. After KDOS treatment, the improvement rates of joint noise and pain were 80.4% and 69.8%, respectively. Additionally, the patients' maximum mouth opening and global QoL mean scores significantly improved compared to those before treatment (p < 0.001). Binary logistic regression analysis revealed that the factors affecting the improvement in the clinical symptoms were disease severity and level of QoL before treatment.

CONCLUSIONS

KDOS can improve the clinical symptoms and QoL of patients with TMD. Moreover, patients without osteoarthritis and with low pretreatment QoL levels are more likely to demonstrate clinical improvement.

TRIAL REGISTRATION

The trial was registered with Chinese Clinical Trial Registry (ChiCTR) (ID: ChiCTR2300076518) on 11/10/2023.

Arthroscopic Assessment of Temporomandibular Joint Pathologies-Is It Possible for Non-Specialists in Arthroscopy? Analysis of Variability and Reliability of Dental Students' Ratings after a Comprehensive One-Semester Introduction

Background: Arthroscopy of the temporomandibular joint (TMJ) plays a long-established role in the diagnostics and therapy of patients suffering from arthrogenic temporomandibular disorders (TMDs), which do not respond adequately to conservative/non-invasive therapy. However, the interpretation of arthroscopic findings remains challenging. This study investigates the reliability and variability of assessing arthroscopic views of pathologies in patients with TMDs by non-specialists in arthroscopy and whether a standardized assessment tool may improve correctness. Methods: Following a comprehensive one-semester lecture, dental students in the clinical stage of education were asked to rate 25 arthroscopic views (freeze images and corresponding video clips) regarding the severity of synovitis, adhesions, and degenerative changes on a scale of 0-10 (T1). The results were compared to ratings stated by two European-board-qualified academic OMF surgeons. In a second round (T2), the students were asked to repeat the ratings using a 10-point rating scheme. Results: With regard to all three subcategories, congruency with the surgeons' results at T1 was at a low level (p < 0.05 in 19/75 cases) and even decreased at T2 after the implementation of the TMDs-SevS (p < 0.05 in 38/75 cases). For both T1 and T2, therefore, the inter-rater agreement was at a low level, showing only a slight agreement for all three subcategories (Fleiss' Kappa (κ) between 0.014 and 0.099). Conclusions: The judgement of the arthroscopic pathologies of the TMJ remains an area of temporomandibular surgery that requires wide experience and training in TMDs to achieve expertise in TMJ arthroscopic assessments, which cannot be transferred by theoretical instruction alone.

Effectiveness of Laser Acupuncture for Reducing Pain and Increasing Mouth Opening Range in Individuals with Temporomandibular Disorder: A Systematic Review and Network Meta-Analysis

PURPOSE OF REVIEW

Laser acupuncture (LA) demonstrates promising results in the treatment of musculoskeletal disorders. However, its effects on temporomandibular disorder (TMD) are not yet fully understood. Thus, the aim of this systematic review and network meta-analysis was to assess the effectiveness of LA on pain intensity and maximum mouth opening range (MMO) related to TMD. A search was carried out in 11 electronic databases and references of included studies to locate randomized clinical trials (RCTs) that evaluated LA as a primary treatment for TMD. The risk of bias was assessed using the RoB 2 tool. Network meta-analysis was conducted on the MetaInsight platform, considering the pain intensity and counseling (C) as the outcome of reference. The GRADE system was used to assess the certainty of the evidence.

RECENT FINDINGS

Five studies evaluated pain intensity, four with a high risk of bias and one with a low risk. Two studies evaluated pain intensity on palpation (one with high and one with low risk of bias), and one study with high risk of bias evaluated MMO. Laser parameters were: 690-810 nm, 40-150 mW, and 7.5-112.5 J/cm2. Occlusal splint (OS) [- 2.47; CI 95% - 3.64, - 1.30] and Physiotherapy (PT) [-2.64; CI 95% - 3.94, - 1.34] reduced pain intensity compared to C. The ranking of treatments in order of effectiveness was PT > OS > LA > C > CR (craniopuncture). The certainty of the evidence was very low or low. The data do not support the indication of LA for the treatment of TMDs and new placebo-controlled RCTs must be conducted to demonstrate its effectiveness more precisely.

Effect of layer thickness and polishing on wear resistance of additively manufactured occlusal splints

OBJECTIVE

To evaluate the effect of polishing and layering thickness on the wear resistance of 3D-printed occlusal splint materials.

METHODS

Specimens with 3 different layer thicknesses (50, 75, 100 µm) were produced in the form of a disc 3 mm thick using V-Print splint resin on a 3D-printer with digital light processing technology. (n = 16 for each thickness) All specimens were washed and cured according to the manufacturer's instructions. Half of the specimens of each layer thickness were polished with silicon carbide papers. All specimens were subjected to 120.000 cycles of a chewing simulator for 2-body wear tests. Before and after the wear test, the specimens were scanned with a laser scanner, and the images were overlaid using a 3D analysis program and the volume loss was calculated. The wear patterns of the specimens were examined under a scanning electron microscope. Statistical evaluation was performed using a Shapiro-Wilk test, 2-way ANOVA, 1-way ANOVA, and Tukey post hoc test (α = 0.05).

RESULTS

While polishing had a significant effect (p = 0.003) on the wear volume of the occlusal splints, layer thickness (p = 0.105) and their interaction between polishing and layer thickness (p = 0.620) did not significantly affect the wear volume. Regardless of the polishing, the lowest mean wear was observed for D50 (0.064 mm3), followed by D75 (0.078 mm3), and D100 (0.096 mm3). However, a significant difference was observed only between polished D50 and unpolished D100.

CONCLUSION

The polished 3D-printed occlusal splint resin showed higher wear resistance than the unpolished one, regardless of the layer thickness.

CLINICAL SIGNIFICANCE

Since different layer thicknesses of 50 µm and greater had no effect on the wear resistance of the material, a layer thickness of 100 µm may be preferred for faster printing. However, polishing occlusal splints may reduce the amount of wear and improve clinical performance.

Knowledge and awareness about temporomandibular disorder among dentists in India: Questionnaire study and review

AIM

Temporomandibular disorders (TMD) comprise ailments involving the jaw joint (temporomandibular joint) and its associated anatomical structures. The complexity involved in TMD is primarily due to its broad spectrum of conditions, clinical signs and symptoms variability, and multifactorial etiology. Considering the above, the present study was performed to help understand the prevailing knowledge and awareness of TMD among Indian dentists in the context of the new specialty "orofacial pain".

SETTINGS AND DESIGN

Questinnaire study and review.

MATERIALS AND METHODS

The questionnaire was distributed using a web-based portal nationwide among Indian dentists. Dentists were invited to participate, clearly stating that the intent and purpose of the questionnaire was to record the existing knowledge and awareness concerning temporomandibular disorders among Indian dentists. The questionnaire was segregated into three sections: pathogenesis, diagnosis, and management of TMDs. The questions were recorded using a Likert three-point scale (1=agree; 2=disagree; 3=not aware). 310 dentists participated in the survey, among which 105 were general dentists (BDS [Bachelor of Dental Surgery] graduates), and 205 were dentists with specialist training (MDS [Masters of Dental Surgery] graduates).

STATISTICAL ANALYSIS USED

The results obtained from the study participants was used to calculate the percentage and frequency, following which tabulations were made based on graduate type and clinical experience. The values obtained from all three sections were recorded, and the responses were analysed using Pearson's Chi-Square test with statistical significance kept at P < 0.05.

RESULTS

Results of the study disclosed that only 58.1% of general dentists and 46.8% of specialists were confident in handling temporomandibular disorder patients. Splint therapy was the preferred treatment modality for general dentists, whereas dentists with specialist training preferred occlusal rehabilitation.

CONCLUSION

The results of the current survey indicate that Indian dentists lack sufficient training in dental schools on all three sections and face difficulty diagnosing and treating TMDs.

Prevalence and associated factors of health anxiety in patients with temporomandibular disorders

OBJECTIVES

To investigate the prevalence and associated factors of health anxiety (HA) in patients with Temporomandibular Disorders (TMDs) using the 8-item Whiteley Index (WI-8) scale.

MATERIALS AND METHODS

Three hundred and twenty-nine TMDs patients completed the Visual Analog Scale (VAS), WI-8, Jaw Functional Limitation Scale-8 (JFLS-8), Patient Health Questionnaire-9 (PHQ-9), and Generalized Anxiety Disorder-7 (GAD-7) scales. Clinical examinations were conducted following the Diagnostic Criteria for TMDs Axis I.

RESULTS

The prevalence of HA among TMDs patients was 18.54%. Patients with HA had higher scores of VAS-current (p = 0.026), VAS-maximum (p = 0.024), VAS-average (p = 0.030), JFLS-8 (p < 0.001), GAD-7 (p < 0.001) and PHQ-9 (p < 0.001), lower maximum mouth opening (p = 0.016), lower proportion of structure-related TMDs (p = 0.028), and higher proportion of pain-related TMDs (p < 0.001) compared to those without HA. The correlation coefficient was 0.61 (p < 0.001) between WI-8 and GAD-7 and 0.64 (p < 0.001) between WI-8 and PHQ-9.

CONCLUSION

Approximately one-fifth of patients with TMDs experienced HA. HA was associated with pain perception, functional limitations, depressive, and anxiety symptoms in individuals with TMDs. HA may contribute to heightened subjective pain experiences rather than structural changes in the TMJ.

Temporomandibular disorder patients with excessive daytime sleepiness present greater pain intensity and reduced jaw function

BACKGROUND

Sleep disorders are associated with temporomandibular disorders (TMDs). Limited studies have focused on excessive daytime sleepiness (EDS) and its impact on jaw functions in TMD patients.

OBJECTIVE

The aim of the present investigation was to identify the impact of EDS on pain and jaw function in TMD patients.

METHODS

A total of 338 TMD patients (50 males and 288 females) was included. The Epworth Sleepiness Scale (ESS) was used to classify patients into EDS group (score ≥ 10) and non-EDS group (score < 10). The Jaw Functional Limitation Scale 8-item (JFLS-8) was used to assess the severity of jaw dysfunction. Pain intensity was evaluated using the Visual Analogue Scale (VAS). Anxiety and depression were evaluated using the Generalised Anxiety Disorder 7-item (GAD-7) and the Patient Health Questionnaire 9-item (PHQ-9). All included patients were diagnosed with pain-related TMD (PT), intra-articular TMD (IT) or combined TMD (CT).

RESULTS

Compared with non-EDS patients, EDS patients exhibited more severe jaw dysfunction, greater pain intensity and higher PHQ-9 scores (p < .05). Multivariate analyses showed that EDS (B = 3.69), female gender (B = 3.69), and elevated GAD-7 score (B = 0.73) were significantly associated with an increased score on the JFLS-8 (p < .05). Moreover, bivariate logistic regression analysis indicated a significant relationship between EDS and PT (OR = 2.70, p = .007).

CONCLUSION

The presence of EDS was more closely related to PT, but the causal relationship between them needs to be further confirmed. More concern and intervention to alleviate poor sleep quality might be highlighted during the treatment of TMD, especially PT subtype.

"Over-reviewing" of research? An analysis of orthodontic reviews

INTRODUCTION

Research overviews may be undertaken to identify gaps in the literature, evaluate existing systematic reviews (SRs), and summarize evidence. This paper aims to profile overviews that have been conducted in orthodontics and related interventions since 2012 and to evaluate the degree of overlap among these overviews.

METHODS

Overviews published between January 1, 2012 and June 20, 2023 were identified using an electronic search involving Google Scholar and PubMed. A descriptive summary was produced, and citation matrices were used to evaluate the percentage of overlap between overviews using corrected covered area and covered area. This was classified as slight, moderate, high, or very high.

RESULTS

A total of 35 overviews were identified across a wide range of topics. Eight overviews included <10 SRs; 21 had 10-20 SRs; and 6 included >20 SRs (median no. of SRs per overview, 15; range, 3-62). Meta-analysis was conducted in only 5 overviews. Overlap between overviews on the same topic ranged from slight (2.7%) to very high (53.8%).

CONCLUSIONS

Almost all overview topics address treatments and their effects, with a wide variation in the number and quality of SRs included. There is considerable overlap in some orthodontic overviews, suggesting unnecessary duplication and research waste. Researchers should be encouraged to focus on primary data collection to add more high-quality data to SRs, which will ultimately enhance the yield from secondary and tertiary orthodontic research.

Impact of professional, recreational and nonsinging on temporomandibular disorders - a comparative study based on a self-assessment questionnaire

BACKGROUND

This study investigates the relationship between professional and recreational singing on temporomandibular disorders (TMDs) in women compared to a nonsinging control group.

METHODS

A total of 288 female subjects between the ages of 18 and 45 participated in the self-assessment questionnaire including demographic data, as well as questions on vocal practice and TMDs symptoms. Depending on the singing time per week, the (non)vocalists were assigned to the groups professional (n = 96), recreational (n = 96) and nonsingers (n = 96).

RESULTS

The TMDs prevalence in professional singers (42%) was higher than that in recreational singers (31%) and noticeably higher than that in nonsingers (25%). The Fisher-Freeman-Halton exact test showed that the differences between the groups were not noticeable (p = .053) but could be formulated as tendencies. The professionals suffered much more from restricted jaw movement (p = .004; OR = 2.718; 95% CI = 1.409-5.242), temporomandibular joint sounds (p < .009; OR = 2.267; 95% CI = 1.264-4.064) and temporomandibular pain (p = .010; OR = 2.333; 95% CI = 1.264-4.308) than nonsingers.

CONCLUSIONS

Singing might have an enhancing effect on the appearance of TMDs. In particular, professional singers suffered more from self-reported TMDs than recreational singers and nonsingers. In addition to the high level of physical workload if participating in professional singing, the psychosocial impact should be investigated more in further studies. No new treatment strategies resulted from this study, as the etiological significance of singing is still unclear. Knowledge about risk factors for multifactorial TMDs can help practitioners and patients prevent and treat TMDs.

Salivary Biomarkers and Temporomandibular Disorders: A Systematic Review conducted according to PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions

BACKGROUND

The present review aimed to investigate the association between salivary biomarkers and temporomandibular disorders (TMD). TMD is a multifactorial condition characterised by pain and dysfunction in the temporomandibular joint (TMJ) and surrounding structures. Salivary biomarkers have emerged as potential diagnostic tools due to their non-invasiveness and easy accessibility. However, the literature on salivary biomarkers in relation to TMD is limited and inconsistent.

METHODS

Electronic databases of Pubmed, Embase, Web of Science, Scopus, Cochrane Library, PsychINFO, CINAHL and Medline were searched using specific search terms and Boolean operators. The search was limited to articles published in English that assessed salivary biomarkers in individuals diagnosed with TMD. Two reviewers independently screened the articles and extracted data. ROB-2 was used to assess the risk of bias.

RESULTS

Eleven clinical papers met the inclusion criteria and were included in the review. The findings provided consistent evidence of a clear association between salivary biomarkers and TMD. Various biomarkers, including cortisol, IL-1, glutamate and several others, were assessed. Some studies reported higher levels of cortisol and IL-1 in TMD patients, indicating potential involvement in stress and inflammation. Glutamate levels were found to be elevated, suggesting a role in pain modulation. Other biomarkers also showed alterations in TMD patients compared to controls: CONCLUSION: The findings from the included studies suggest that salivary biomarkers may play a role in TMD pathophysiology. Though a definitive conclusion can be drawn regarding the specific salivary biomarkers and their association with TMD, the results must be interpreted with caution considering the heterogeneity of the biomarkers assessed. Further research with larger sample sizes, standardised methodology and rigorous study designs is needed to elucidate the role of salivary biomarkers in TMD.

Comparative analysis of different types of occlusal splints for the management of sleep bruxism: a systematic review

BACKGROUND

Sleep bruxism is a prevalent condition in dentistry practice, characterized by involuntary grinding or clenching of the teeth during sleep. Several therapies, including occlusal splints, have been used to manage sleep bruxism and temporomandibular disorders, including occlusal splints. This study aimed to compare the effectiveness of different occlusal splints in managing sleep bruxism.

METHODS

The PICO framework encompasses the characterization of the population, intervention, comparison, and pertinent outcomes. A comprehensive and systematic literature review was conducted on PubMed, Scopus, and Google Scholar to identify grey literature. The search specifically targeted scientific studies published before September 20, 2023. The Cochrane Collaboration Risk of Bias Tool assessed the accuracy of the included Randomized Control Trials (RCTs). The modified Newcastle-Ottawa Scale assessed non-randomized studies. Data were systematically extracted, synthesized, and reported thematically.

RESULTS

Out of the total of 808 articles that were evaluated, only 15 articles were found to meet the specified inclusion criteria. Adjustable splints, such as full-occlusion biofeedback splints, were more effective in reducing sleep bruxism episodes, improving patient-reported symptoms, and enhancing overall well-being. The impact of different occlusal sprints on electromyographic activity varies, and potential adverse effects should be considered individually.

CONCLUSIONS

This review provides valuable insights into the effectiveness of occlusal splints in managing sleep bruxism. The results of this study indicate that occlusal splint therapy is a viable treatment approach for sleep bruxism.

Low income is associated with impaired jaw function via anxiety and depression in patients with temporomandibular disorders

OBJECTIVE

The association between jaw function and income in patients with temporomandibular disorders (TMDs) remain unclear. The aim of this study was to explore this association and its relationship with anxiety and depression.

SUBJECTS AND METHODS

A total of 451 TMD patients, including 361 males and 90 females, participated in this study. The sociodemographic information of patients and their questionnaires including the Generalised Anxiety Disorder 7-item (GAD-7), Patient Health Questionnaire 9-item (PHQ-9), and Jaw Functional Limitation Scale-8 (JFLS-8) were collected. Patients were divided into the high-income and low-income groups based on a household per capita income of 6000 RMB per month. Multiple regression and mediation analysis were used to explore the association between variables. The bootstrap method was applied to estimate confidence intervals (CIs).

RESULTS

Higher JFLS-8 scores were significantly correlated with higher GAD-7 scores (r = 0.361, p < .001), PHQ-9 scores (r = 0.339, p < .001). Females and patients with low income had statistically higher JFLS-8 scores (p < .01, p < .001). Mediation analysis with 10 000 bootstrap simulations revealed a significant direct association between JFLS-8 scores and income (-2.920, 95% CI [-4.757, -1.044], p = .002). A significant indirect association of JFLS-8 scores with income via GAD-7 scores and PHQ-9 scores was also observed (-0.889, 95% CI [-1.728, -0.164], p = .025), accounting for 23.3% of the total association.

CONCLUSIONS

Low income is associated with impaired jaw function via anxiety and depression in patients with TMD. Clinicians may need to pay more attention to the psychological status of low-income TMD patients in clinical practice.

Remodeling dental anatomy vs sham therapy for chronic temporomandibular disorders. A placebo-controlled randomized clinical trial

BACKGROUND

Evidence regarding the etiology or effective treatments for chronic orofacial pain, the majority diagnosed as temporomandibular disorder (TMD), is limited.

PURPOSE

To investigate whether occlusal equilibration therapy (ET) and decreasing the (higher) angle of the lateral guidance on the nonworking-side leads to a reduction in chronic TMDs intensity.

METHODS

It was conducted a randomized, explanatory, single blind with blinded assessment, placebo-controlled trial with strong protection against bias involving patients with chronic TMDs. Participants were randomly assigned to receive equilibration therapy or sham therapy. ET in this study consisted of minimal invasive occlusal remodeling to obtain balanced occlusion with reduction of the steeper angle of lateral mandibular movement with respect to the Frankfort plane. The primary outcome was a change in the pain intensity score (on a 0-10 point scale, with 0 indicating no pain and 10 the worst possible pain) at month 6. Secondary outcomes include maximum unassisted mouth opening and psychological distress.

RESULTS

A total of 77 participants underwent randomization, 39 of whom received ET and 38 sham therapy. The trial was stopped early for efficacy, according to preestablished rules when 67 participants (n = 34, n = 33, respectively) had completed the analysis. At month 6, the mean unadjusted pain intensity score was 2.1 in the ET and 3.6 in the sham therapy group (adjusted mean difference, -1.54; 95% confidence interval [CI] -0.5 to -2.6; P = 0.004; ANCOVA model). The mean increase in maximum unassisted mouth opening (main secondary outcome) was significantly higher in the real therapy group (adjusted mean difference 3.1 mm, 95% CI 0.5-5.7, p = 0.02).

CONCLUSION

ET significantly reduced the intensity of facial pain associated with chronic TMDs and increased maximum unassisted mouth opening, as compared with sham therapy, over the course of 6 months. There were no serious adverse events. Funded by the Instituto de Salud Carlos III from the Ministry of Science and Innovation of the Government of Spain and European Regional Development Fund, Grant nº PI11/02507; "una manera de hacer Europa".

Post-traumatic stress, prevalence of temporomandibular disorders in war veterans: Systematic review with meta-analysis

INTRODUCTION

The physical and psychological effects of war are not always easy to detect, but they can be far-reaching and long-lasting. One of the physical effects that may result from war stress is temporomandibular disorder (TMD).

OBJECTIVE

To evaluate the prevalence of TMD sign and symptoms among war veterans diagnosed with PTSD.

METHODS

We systematically searched in Web of Science, PubMed and Lilacs for articles published from the inception until 30 December 2022. All documents were assessed for eligibility based on the following Population, Exposure, Comparator and Outcomes (PECO) model: (P) Participants consisted of human subjects. (E) The Exposure consisted of exposition to war. (C) The Comparison was between war veterans (subjects exposed to war) and subjects not exposed to war. (O) The Outcome consisted of presence of temporomandibular disorders sign or symptoms (we considered pain to muscle palpation in war veterans).

RESULTS

Forty studies were identified at the end of the research. We chose only four study to draw up the present systematic study. The included subjects were 596. Among them, 274 were exposed to war, whereas the remaining 322 were not exposed to war stress. Among those exposed to war, 154 presented sign/symptoms of TMD (56.2%) whereas only 65 of those not exposed to war (20.18%). The overall effect revealed that subjects exposed to war and diagnosed with PTSD had a higher prevalence of TMD signs (pain at muscle palpation) than controls (RR 2.21; 95% CI: 1.13-4.34), showing an association PTSD war-related and TMD.

CONCLUSIONS

War can cause lasting physical and psychological damage that can lead to chronic diseases. Our results clearly demonstrated that war exposure, directly or indirectly, increases the risk of developing TMJ dysfunction and TMD sign/symptoms.

Does the Use of Injectable Platelet-Rich Fibrin After Arthrocentesis for Disc Displacement Without Reduction Improve Clinical Outcomes?

PURPOSE

Many studies have reported the role of arthrocentesis to alleviate symptoms of patients with disc displacement without reduction (DDWoR). Nevertheless, the benefit of injectable platelet-rich fibrin (i-PRF) remains unclear. The aim of this study was to answer the following question: among patients with DDWoR, do those treated with intra-articular injection of i-PRF after arthrocentesis, when compared to those treated with arthrocentesis only, have better clinical outcomes in terms of pain reduction and improvement of jaw movement?

MATERIALS AND METHODS

This single-blind randomized, controlled study included patients with diagnosed DDWoR, in the Department of Oral and Maxillofacial Surgery at the School of Dentistry, Ege University, who had localized joint pain and limited range of motion. Patients were treated either with arthrocentesis (AC group) or arthrocentesis in combination with intra-articular i-PRF injection (AC + i-PRF group). The predictor variable was treatment (ie, arthrocentesis with or without i-PRF). The primary outcome variable was pain (visual analog scale). The secondary outcome variables were maximum mouth opening, lateral and protrusive movements. Outcome variables were recorded at pretreatment and at the postoperative 1st, 2nd, 3rd, 6th, and 12th months. Statistical analysis was performed using the Brunner-Langer model, with a significance level P < .05.

RESULTS

This study comprised 76 patients (34 females/4 males, mean age 47.2 ± 9.1 for the AC + i-PRF group; 35 females/3 males, mean age 46.8 ± 10.2 for the AC group). The treatment success rate was 73.7% for the AC group and 100% for the AC + i-PRF group (P = .012). Pain levels in the AC + i-PRF group were found to decrease more than the AC group over 12 months postoperatively (palpation: -6.9 ± 1.2 vs -5.3 ± 1.3; chewing: -6.9 ± 1.5 vs -5.1 ± 1.7; jaw movements: -6.9 ± 1.1 vs -5.1 ± 1.4). This difference was statistically significant (P < .001). The degree of jaw movement in the AC + i-PRF group was found to increase more than the AC group over 12 months postoperatively (maximum mouth opening: 8.0 ± 2.1 vs 4.9 ± 2.0; contralateral: 1.8 ± 0.8 vs 0.2 ± 1.0; ipsilateral: 2.9 ± 1.3 vs 0.8 ± 1.5; protrusive: 2.6 ± 1.1 vs 0.8 ± 1.3). This difference was statistically significant (P < .001).

CONCLUSION

Intra-articular injection of i-PRF after arthrocentesis produced greater improvements in pain reduction and jaw movement when compared to arthrocentesis only. These results indicate that i-PRF used in combination with arthrocentesis is an effective adjunctive treatment.

Oral splints in the management of nociceptive pain and migraines: A scoping review

Temporomandibular disorders (TMDs) are characterized by numerous pain manifestations. Their treatment often involves the use of an oral splint. Recent research has found a relationship between migraines, nociceptive pain and TMDs. The aim of the present study was to perform a scoping review of studies in order to evaluate the effectiveness of the various types of oral splint in the treatment of migraine or nociceptive pain. Publications were retrieved from seven databases (PubMed, Web of Science, EMBASE, Scopus, ProQuest, SpringerLink and Ovid). Out of the 15 included publications, three studies were before and after studies, with no control group, whereas the other twelve studies were clinical trials, among which two publications were crossover studies. A clear, single distinction of pain was difficult to describe. Therefore, numerous publications focused on a combination of various types of pains, including myofascial, temporomandibular joint, headaches and migraine-like symptoms, all of which mimicked TMD pain. Overall, six studies used the stabilization splint (SS), three explored the comparison between the SS and the nociceptive trigeminal inhibition splint (NTIS) and two the NTIS. The majority of publications reported a positive outcome of splint therapy. Regarding the type of oral splint usage, the most commonly used one was the SS, followed by the NTIS. The definition and assessment of pain were heterogenous in the identified articles. The findings of the current study showed that occlusal splints may help with pain management, and that effective treatment of TMD-related pain at an early stage can enhance the quality of life of patients.

TMEM100, a regulator of TRPV1-TRPA1 interaction, contributes to temporomandibular disorder pain

There is an unmet need to identify new therapeutic targets for temporomandibular disorder (TMD) pain because current treatments are limited and unsatisfactory. TMEM100, a two-transmembrane protein, was recently identified as a regulator to weaken the TRPA1-TRPV1 physical association, resulting in disinhibition of TRPA1 activity in sensory neurons. Recent studies have also shown that Tmem100, Trpa1, and Trpv1 mRNAs were upregulated in trigeminal ganglion (TG) after inflammation of the temporomandibular joint (TMJ) associated tissues. These findings raise a critical question regarding whether TMEM100 in TG neurons is involved in TMD pain via regulating the TRPA1-TRPV1 functional interaction. Here, using two mouse models of TMD pain induced by TMJ inflammation or masseter muscle injury, we found that global knockout or systemic inhibition of TRPA1 and TRPV1 attenuated pain. In line with their increased genes, mice exhibited significant upregulation of TMEM100, TRPA1, and TRPV1 at the protein levels in TG neurons after TMD pain. Importantly, TMEM100 co-expressed with TRPA1 and TRPV1 in TG neurons-innervating the TMJ and masseter muscle and their co-expression was increased after TMD pain. Moreover, the enhanced activity of TRPA1 in TG neurons evoked by TMJ inflammation or masseter muscle injury was suppressed by inhibition of TMEM100. Selective deletion of Tmem100 in TG neurons or local administration of TMEM100 inhibitor into the TMJ or masseter muscle attenuated TMD pain. Together, these results suggest that TMEM100 in TG neurons contributes to TMD pain by regulating TRPA1 activity within the TRPA1-TRPV1 complex. TMEM100 therefore represents a potential novel target-of-interest for TMD pain.

The Effect of Individual Nursing on Anxiety and Depression in Patients with Temporomandibular Disorders

Objective

This study aimed to explore the effects of individualized nursing in patients with temporomandibular disorders (TMD).

Methods

From June 2019 to April 2021, 80 patients with TMD were admitted to the First Affiliated Hospital of Wenzhou Medical University. Among them, 40 patients (control group, CG) received routine nursing and 40 patients (experimental group, EG) received individualized nursing. Functional exercise compliance, pain score, maximum mouth opening, nursing satisfaction questionnaire, self-rating anxiety scale, and self-rating depression scale were investigated.

Results

From June 2019 to April 2021, 81 patients with TMD were admitted to the First Affiliated Hospital of Wenzhou Medical University. Among them, 40 patients (control group) received routine care and 41 patients (experimental group) received individual care. There were no significant differences in mouth opening and pain score between the two groups before surgery (P > 0.05), but there were significant differences in mouth opening and pain score between the two groups 3 weeks after surgery. Patients' anxiety and depression were assessed by the SAS and SDS scores. Before nursing, the control group and experimental group (P < 0.05) had no significant difference. After nursing, the score of both groups decreased (P < 0.05). However, the score was lower in the experimental group, compared to the control group (P < 0.01).

Conclusion

In summary, individualized nursing can improve patients' physical condition and reduce negative emotions and complications. In light of this, the study needs further verification by a large sample randomized controlled trial.

Use of the Temporalis Myofascial Flap in Internal Derangement of the Temporomandibular Joint - An Evaluative Study

Introduction

Internal derangement is an abnormal relationship between the articular disc and the mandibular condyle. The most common cause is trauma. Various classifications have been given for internal derangement. Initial management is done conservatively and if the disease is progressed, surgery is the option. Various surgical methods and interpositional materials following discectomy have been given in the literature.

Materials and Methods

Over the past 15 years, we selected a group of 30 patients, Wilkes Class IV and V where conservative therapy had failed and were candidates for surgery. The patients had their disc repositioned, the damaged part of the disc was excised and disc was reinforced using the temporalis myofascial flap (TMF). In cases where the disc was non-salvageable, discectomy was done and TMF was placed between condyle and glenoid fossa, sutured with Prolene. The follow-up period was 3 years.

Results

Of the 30 patients, there were 9 male and 21 female. Range of mouth opening was 3.3-3.8 cm with improvements in 1 year. The jaw relations gradually improved and were restored after 3 weeks. Patients were totally pain free in 6 months.

Discussion

For the cases where surgery is the line of treatment, we strongly suggest disc repositioning and reinforcement with TMF as the flap is bulky, locally available and easy to harvest and causes no deformity at the donor site.