Research diagnostic criteria for temporomandibular disorders: a systematic review of axis I epidemiologic findings

Syndecan-4 inhibition attenuates cartilage degeneration in temporomandibular joint osteoarthritis

BACKGROUND

Syndecan 4 (SDC4), a type I transmembrane proteoglycan, serves as a critical link between chondrocytes and the extracellular matrix.

OBJECTIVE

This study aimed to explore the role of SDC4 in cartilage degeneration of temporomandibular joint osteoathritis (TMJOA).

METHODS

Condylar chondrocytes were stimulated with varying concentrations of recombinant rat interleukin-1β (rrIL-1β) and SDC4 small interfering RNA (si-SDC4). Anti-SDC4 ectodomain-specific antibodies or IgG were intra-articularly administrated in a TMJOA model rats. SDC4 conditional knockout (SDC4-cKO) and Sdc4flox/flox mice were induced TMJOA. Cartilage degeneration was assessed using haematoxylin & eosin (H&E) and safranin O (SO) staining. Protein levels of SDC4, matrix metalloproteinases (MMPs), a disintegrin and metalloproteinase with a thrombospondin motifs 5 (ADAMTS5), tumour necrosis factor α (TNFα), type II collagen (Col-II), aggrecan (ACAN), cleaved caspase 3 (CASP3), Ki67 and related pathways in condylar cartilage were evaluated by immunohistochemical (IHC) staining or western blot assays.

RESULTS

SDC4 expression was evidently increased in MIA-model animals compared to control groups. rrIL-1β stimulation increased the expression of SDC4, MMP3 and ADAMTS5 expression in chondrocytes, while decreasing the expression of Col-II. These effects were reversed by si-SDC4 in vitro. In vivo, SDC4 blockade reduced the death of chondrocytes and the loss of cartilage matrix, which was evidenced by increased expression of Col-II and ACAN, and a decrease in SDC4, MMP13 and cleaved-CASP3-positive cells. Furthermore, the protein levels of ACAN and Ki67 were elevated, and the ERK1/2 and P38 signalling pathways were activated following SDC4 inhibition.

CONCLUSIONS

SDC4 inhibition significantly ameliorates condylar cartilage degeneration, which was mediated, at least partly, through P38 and ERK1/2 signalling. Inhibition of SDC4 may be of great value for the treatment of TMJOA.

The influence factors on pit and fissure sealing behavior of 12-year-old children: a cross-sectional study in Zhejiang, China

BACKGROUND

In the 21st century, dental caries remains a global burden, particularly severely affecting the growth and quality of life of 12-year-old children. Fortunately, pit and fissure sealing (PFS) procedures can effectively prevent molars from caries. Hence, this study focused on the relationship between PFS and oral epidemiological factors in 12-year-old children.

METHODS

A cross-sectional survey was conducted in 12-year-old children from 11 cities in Zhejiang Province. Their dental conditions were collected through questionnaires, as well as basic information such as relevant family information, oral health knowledge and behavior. Then, logistic regression analysis was used to identify the influencing factors associated with PFS.

RESULTS

A total of 1204 children were included, with 252 in the PFS group and 952 in the non-PFS group. There were significant differences between the two groups in terms of decayed, missing and filled teeth (DMFT) score, first permanent molar DMFT score, residential area, educational level of parents, tooth-brushing frequency, use of dental floss, oral examination in a medical institution, having taken courses on oral health care, as well as having knowledge that tooth brushing could effectively prevent gingival inflammation, PFS could protect teeth, and oral disease may affect general health. According to further logistic regression analysis, the independent factors influencing PFS included use of dental floss [odds ratios (OR) = 1.672, 95% confidence intervals (CI) = 1.235-2.263, P = 0.001], having taken courses on oral health care (OR = 0.713, 95% CI = 0.515-0.988, P = 0.042), having knowledge that tooth brushing is effective in preventing gingival inflammation (OR = 0.627, 95% CI = 0.389-0.987, P = 0.044) and having knowledge that PFS can protect teeth (OR = 0.589, 95% CI = 0.438-0.791, P < 0.001).

CONCLUSION

PFS can reduce the mean DMFT score of 12-year-old children. Independent influencing factors of PFS consist of use of dental floss, having taken courses on oral health care, oral health behavior and knowledge level.

Cross-Cultural Validation of the Thai Oral Health Impact Profile for Temporomandibular Disorders

OBJECTIVES

The Oral Health Impact Profile for Temporomandibular Disorders (OHIP-TMDs) is a validated condition-specific outcome measure to help guide decision-making in the management of the condition. There is no Thai version of OHIP-TMDs, and therefore the original English version needs cross-cultural adaptation translation, and validation with a Thai population to reduce the anomalies due to language and cultural differences. This study aimed to develop the Thai-language version of OHIP-TMDs, perform a cross-cultural adaptation to Thailand, and assess its content validity, internal consistency, reliability, and construct validity.

METHODS

The original English version of OHIP-TMDs was forward and backward translated into Thai language using the International Network for Orofacial Pain and Related Disorders methodology (INfORM) protocol for cross-cultural adaptation. The Content Validity Index (CVI) was performed by 5 orofacial pain (OFP) specialists to establish content validity. The OHIP-TMDs-T was then tested in 2 groups of Thai dental patients including 110 TMD patients and 110 control participants. The internal reliability and test-retest reliability (n = 30) were investigated in the TMD group using Cronbach alpha coefficient and intraclass correlation coefficient (2-way mixed effect model), respectively. The difference in OHIP-TMDs-T score between the TMD group and control group was investigated for known group validity.

RESULTS

Cronbach alpha and intraclass correlation coefficients were 0.942 and 0.797, respectively. The CVI collected from the OFP specialists was 0.92. There was a statistical difference in the OHIP-TMDs-T overall score between the TMD group (95% CI, 40-46) and control group (95% CI, 2.0-3.4) (Z = 9.060, r = 1, P < .001).

CONCLUSIONS

The OHIP-TMDs-T is a valid and reliable tool for evaluating the quality of life and the impact on oral health in Thai patients with TMD.

Oral habits and temporomandibular joint disorders according to stress levels among military personnel in South Korea: A cross-sectional study

BACKGROUND

Military personnel suffer from stress-induced temporomandibular joint disorders (TMD). No previous studies have evaluated the oral habits and TMD in military personnel based on their stress levels.

OBJECTIVES

To examine the correlation between oral habits and TMD based on stress levels. In addition, we assessed the relationship between stress levels and TMD by military rank as well as the impact of oral habits on TMD.

METHOD

This cross-sectional survey included 89 military personnel who visited the Armed Forces Medical Center in Korea with discomfort in the temporomandibular joint (TMJ) discomfort. Oral habits, stress level, TMD and general characteristics of the subjects were investigated. A questionnaire was distributed to the subjects who agreed to the study, and they were asked to respond in a self-written form. Multiple linear regression analysis was performed to examine the factors that affect oral habits and TMJ symptoms.

RESULTS

Stress scores and oral habits were highest in the 'Private' rank. In contrast, temporomandibular joint symptoms were highest in the 'Corporal' rank. Additionally, the high-risk stress group exhibited higher scores in oral habits and TMD compared to the potential stress group. Furthermore, there was a positive correlation between an increase in high-risk stress scores and a rise in oral habits. And individuals with more oral habits are at an increased likelihood of experiencing TMD.

CONCLUSION

Our study findings suggest that military personnel with prevent TMD and improve oral habits by addressing stress levels.

Physical therapy in addition to occlusal splint in myogenic temporomandibular disorders: A randomised controlled trial

BACKGROUND

Myogenic temporomandibular disorders (M-TMD) commonly involve occlusal splint (OS) therapy and musculoskeletal physiotherapy (MPT).

OBJECTIVES

To compare the effects of combining OS with MPT and education (EG) against OS and education (CG), in chronic M-TMD patients.

METHODS

In this double-blind randomised controlled trial, 62 participants were assigned to either EG or CG. The primary outcomes, pain levels at rest (VAS rest), maximum oral opening (VAS open) and during chewing (VAS chew), were measured by Visual Analogue Scale (VAS) in cm. The secondary outcome was the range of motion (ROM) for maximum oral opening. Both interventions lasted 3 months, with outcomes assessed at baseline (T0), post-treatment (T1) and 3 months post-treatment (T2).

RESULTS

Intention-to-treat analysis revealed significant improvements favouring EG (VAS rest = -1.50 cm [CI95%: -2.67, -0.32], p = .04; VAS open = -2.00 cm [CI95%: -3.23, -0.75], p < .01; VAS chew = -1.71 cm [CI95%: -2.90, -0.52], p = .01; ROM = 4.61 [CI95%: 0.93, 8.30], p = .04). Additionally, VAS measures were influenced by follow-up times (VAS rest = -0.73 cm [CI95%: -1.30, -0.17], p = 0.03; VAS open = -0.97 cm [CI95%: -1.57, -0.37], p < .01; VAS chew = -1.15 cm [CI95%: -1.73, -0.58], p < .01). At T1, EG demonstrated higher number of responders compared to CG for VAS open (χ2(1) = 4.39, p = .04) and VAS chew (χ2(1) = 11.58, p < .01).

CONCLUSION

Adding MPT to education and OS yields better outcomes in terms of pain reduction and ROM improvement, in chronic M-TMD.

TRIAL REGISTRATION NUMBER

NCT03726060.

Conceptualising TMD symptom burden in youths: Symptom duration, frequency, intensity and interference

OBJECTIVE

This study aimed to conceptualise Temporomandibular disorder (TMD) symptom burden and severity and explored their interrelationships with somatic symptoms and psychological distress.

METHODS

Participants were recruited from a local polytechnic. The quintessential five TMD symptoms (5Ts) of the Diagnostic Criteria for TMDs (DC/TMD) were appraised and extended to evaluate the duration, frequency, intensity and interference of discrete TMD symptoms. Global TMD severity (GS) was computed by totaling the points for all TMD symptoms and dimensions. TMD (TS) and somatic symptom (SS) burden were assessed based on the Somatic Symptoms Scale-8, while psychological distress was measured with the Depression, Anxiety and Stress Scales-21. Statistical analyses were performed using Kruskal-Wallis/Dunn tests and Spearman's correlation (α = .05).

RESULT

Of the 366 eligible participants (mean age 19.1 ± 2.3 years), 51.4% were 5Ts-negative and 48.6% were 5Ts-positive. Among the 5Ts-positive individuals, 25.3%/64.0% were 'bothered a little' whereas 4.5%/10.7% were 'bothered a lot' by TMD pain/headache. Correspondingly, 32.6%/12.4%/5.1% were 'bothered a little' while 2.8%/2.8%/1.1% were 'bothered a lot' by TMJ sounds/closed/open locking. TS burden was moderate-to-strongly correlated to aggregate symptom duration, frequency, intensity, interference, GS and SS burden (rs = .50-.88). While TS burden and GS were weakly associated with psychological distress (rs = .18-.36), SS burden was moderately related to depression, anxiety and stress (rs = .47-.53).

CONCLUSIONS

TS burden can serve as a proxy for global TMD severity and may be more meaningful than the mere presence of TMD symptoms in clinical and research settings.

Temporomandibular disorder pain is associated with increased sick leave and reduced health related quality of life

BACKGROUND

Temporomandibular disorders (TMD) are the most common reason for chronic pain in the orofacial area and significantly impact the lives of those affected. The role of lifestyle factors in TMD, however, remains less explored. This cohort study aims to estimate TMD prevalence by addressing potential selection biases and to evaluate the association between TMD and lifestyle factors with a specific focus on sick leave and health related quality of life.

METHODS

By linking data on TMD in the general population in Västerbotten, northern Sweden (n = 180,000) to health survey data (n = 120,000), information on sociodemographic factors and quality of life was available for 52,961 individuals (50.6% women) with a mean age of 53 years. We applied inverse probability weighting to adjust for selection bias and Poisson regression to explore associations with TMD.

RESULTS

TMD prevalence was 9.2% during the study period, being higher in women (12.9%) than men (5.4%). Weighting for varying visiting frequencies did not affect TMD prevalence (average difference 0.4% points). Individuals with TMD, especially women, reported more sick leave and use of pain medication, with a significant association between TMD and increased sick leave (prevalence ratio 1.89, 95% CI: 1.78-2.01) among both women and men. In addition, TMD was associated with a lower health related quality of life (p < 0.001).

CONCLUSION

The association of TMD with sick leave highlights the condition's profound impact on the lives of affected individuals. These findings underscore the influence of TMD on work life and the burden of TMD on the societal level.

SIGNIFICANCE STATEMENT

The findings provide insight into how TMD affect individuals, by incorporating lifestyle factors, social determinants and the impact of sick leave at a population level. By incorporating these areas into the study of TMD, we can deepen our understanding of how TMD affects individuals' lives. This approach may also create opportunities to develop more comprehensive strategies to address TMD, focusing on broader implications beyond the clinical symptoms.

Ultrasonographic characteristics of myogenous temporomandibular disorders: A scoping review

OBJECTIVE

To identify the available evidence on the ultrasonographic characteristics of masticatory muscles in subjects with myogenous TMD, as well as the potential use of ultrasonography as a diagnostic and treatment assessment outcomes tool.

METHOD

An electronic search of the PubMed, Web of Science and Scopus databases was performed using the following terms: 'ultrasonography', 'ultrasound', 'masseter', 'temporal', 'masticatory muscles', 'temporomandibular disorders', 'temporomandibular joint disorders'. Full-text articles were obtained from the records after applying the inclusion/exclusion criteria.

RESULTS

Thirteen articles were included for analysis: one comparative cross-sectional study, five case-control studies, six clinical trials and one randomised clinical trial. Main ultrasonographic characteristic assessed were local cross-sectional dimension and intramuscular ultrasonographic appearance. Retrieved studies reported the use ultrasonography for diagnosis or treatment assessment purposes showing heterogeneous results. For diagnosis purposes, the results of local cross-sectional dimension are not consistent; therefore, its diagnostic value for myogenous TMD diagnosis is weak. However, more homogeneous results were observed for intramuscular ultrasonographic appearance showing a higher prevalence of type-II pattern in myogenous TMD subjects than non-TMD subjects. On the other hand, for treatment assessment purposes, muscles were observed thinner after treatment compared to pre-treatment. Also, results of intramuscular ultrasonographic appearance show disappearance or reduction of anechoic areas, higher prevalence of type-II pattern and significant distinction of echogenic bands were observed after treating TMD subjects.

CONCLUSION

Ultrasonography cannot be considered as a diagnostic instrument, but maybe as a complementary tool for treatment assessment of myogenous TMD subjects, even though future research is required to confirm its utility.

Clinical outcomes of patients with unilateral internal derangement of the temporomandibular joint following arthrocentesis and stabilization splint therapy

BACKGROUND

The management of internal derangement (ID) of the TMJ is challenging because of multiple etiologic factors and varying degrees of severity. The aim of this study was to evaluate the clinical outcomes of patients with unilateral ID treated with arthrocentesis and stabilization splint therapy during a 6-month period.

METHODS

A total of 105 patients (87 females, 18 males) with unilateral ID were included in this study. Patients were divided into unilateral anterior disc displacement with reduction (ADDwR) and unilateral anterior disc displacement without reduction (ADDwoR). Patients with ADDwoR were subdivided according to the erosive bone changes. Objective parameters on mandibular movement and subjective parameters on pain were obtained and assessed. Their clinical outcomes before and after arthrocentesis and stabilization splint therapy were compared with the chi-square, Fisher's exact test, paired t-test, or Wilcoxon singed-rank test.

RESULTS

All objective parameters of unilateral ID patients significantly increased at the 6-month follow-up. The differences in mean visual analog scale (VAS) pain scores were statistically significant in all subjective variables (p < 0.01). In joints with ADDwoR, preoperative maximal mouth opening, and maximal protrusive movement in both groups, with erosive and non-erosive changes were significantly increased after 6 months (p < 0.01). However, right and left maximal lateral movement increased after treatment in both groups but without significant differences. All VAS pain scores on jaw movement and palpation of associated muscles showed a significant decrease regardless of erosive changes.

CONCLUSIONS

The combination of arthrocentesis and subsequent stabilization splint therapy was shown to be highly effective in pain reduction and improvement of mandibular movements in both unilateral ADDwR and ADDwoR, as well as in cases with both erosive and non-erosive bony changes associated with unilateral ADDwoR.

Clinical benefit of botulinum toxin for treatment of persistent TMD-related myofascial pain: A randomized, placebo-controlled, cross-over trial

BACKGROUND

Injections of botulinum toxin type A (BoNT-A) have been proposed as an additional treatment modality for patients suffering chronic temporomandibular disorder (TMD)-related myofascial pain (MFP). BoNT-A impairs muscle function, along with its analgesic effect, and a minimal effective dose should be used. The objective of this randomized placebo-controlled crossover study was to evaluate the clinical benefit of a moderate dose (50 U) of BoNT-A.

METHODS

Sixty-six subjects were randomized into two groups, one which received BoNT-A first and a second which received a saline solution (SS) first. Follow-ups were performed 2, 11, and 16 weeks after the injections. Diagnostic criteria for temporomandibular disorders (DC/TMD) diagnostic algorithms were used to evaluate characteristic pain intensity (CPI) and pain-related disability based on the Graded Chronic Pain Scale (GCPS). Electromyographic and bite force were also evaluated.

RESULTS

The within-group analysis showed a significant improvement in pain intensity and pain-related disability after BoNT-A (p < 0.001, p = 0.005, p = 0.011) and SS (p = 0.003, p = 0.005, p = 0.046) injections up to week 16. The between-group analysis of pain-related variables revealed no differences between groups at any time. Nonetheless, BoNT-A, but not SS, caused a significant decline in muscle performance. The number needed to treat (NNT) regarding a clinically significant pain reduction (≥30%) was 6.3, 57.0, and 19.0 at 2, 11, and 16-week follow-ups favoring BoNT-A.

CONCLUSIONS

Injections of 50 U of BoNT-A might improve MFP symptoms, but the specific effect of the drug on pain compared to the placebo is not obvious.

Exploring the effect of disc displacement on the risk and severity of condylar erosion in adult temporomandibular disorder patients: A CBCT and MRI study

OBJECTIVE

The objective of the study was to investigate the relationship between types of disc displacement (DD) diagnosed by magnetic resonance imaging (MRI), and the risk (presence or absence) and severity of condylar erosion (CE) graded using cone-beam computed tomography (CBCT) in adult Temporomandibular disorders (TMD) patients.

METHODS

A total of 353 TMD patients (283 females, 70 males) underwent MRI scans to categorise DD as normal (NA), anterior displacement with reduction (ADDR), or anterior displacement without reduction (ADDNR). CE severity was graded on a scale of 0-3 (absence, mild, moderate or severe) using CBCT. To establish the plausibility and cut-off points for CE diagnosis, the severity of CE was then further divided into three classifications: Grade 0 versus 1 + 2 + 3; Grades 0 + 1 versus 2 + 3; Grades 0 + 1 + 2 versus 3. Logistic regression analysis was performed, adjusting for age, gender and joint correlation.

RESULTS

ADDNR significantly increased the risk of CE compared with NA (OR = 10.04, 95% CI: [6.41, 15.73]) and showed a significant increase in CE severity across all classifications (ORs = 10.04-18.95). The effects of ADDNR were significant in both genders (p < .001) and had a greater impact in females. ADDR was predominantly associated with mild CE.

CONCLUSIONS

ADDNR significantly increased the risk and severity of CE independent of gender when compared to NA, whereas ADDR was mainly associated with mild CE. Slight cortical discontinuity may represent a subclinical diagnosis requiring further investigation.

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.

Temporomandibular Disorders in Relation to Mandibular Advancement Devices for Treating Obstructive Sleep Apnea

Mandibular advancement devices (MADs) keep the upper airways patent by holding the mandible and attached soft tissues forward via altered position of its condyles relative to the articulating surfaces of the temporal bones. During the first weeks of MAD therapy, pain may occur in the area of the temporomandibular joints, masticatory muscles, and/or teeth with a tendency of spontaneous resolution. In patients reporting temporomandibular disorder (TMD) symptoms prior to therapy, the MAD-related anterior condylar position during sleep may result in a reduction of TMD signs and symptoms.

Psychometric properties of the Indonesian Fonseca anamnestic index and the presence/severity of temporomandibular disorders among Indonesian young adults

OBJECTIVE

The psychometric properties of the Indonesian FAI (FAI-I) and presence/severity of temporomandibular disorders (TMDs) among Indonesian young adults were explored.

METHODS

The FAI-I was developed following the INfORM guidelines and used to determine the presence/severity of TMDs. Internal consistency/test-retest reliability were examined with Cronbach's alpha/intra-class correlation (ICC) coefficients. Construct/criteria validity were established by correlating (Spearman) the FAI-I to the five major TMD symptoms (5 Ts) and OHIP-14 (p < 0.05).

RESULTS

Five hundred-one participants (mean age 19.73 ± 1.27 years; 75.2% women) were recruited from a local University. Of these, 40.7% had no TMD, while 49.9%, 8.8%, and 0.6% had mild, moderate, and severe TMD. While Cronbach's α = 0.57 and ICC = 0.72, correlation coefficients to total 5 Ts and OHIP-14 were 0.53 and 0.47, respectively.

CONCLUSION

The FAI-I had low internal consistency, good test-retest reliability, and good validity. Moderate-to-severe TMD was experienced by 9.4% of the young adults examined.

Elevated pain sensitivity is associated with reduced rapid eye movement (REM) sleep in females with comorbid temporomandibular disorder and insomnia

OBJECTIVE

Patients with chronic pain disorders, including Temporomandibular Disorders (TMDs) endorse high levels of sleep disturbances, frequently reporting reduced sleep quality. Despite this, little is known about the effect that daytime pain has on the microstructure and macro-architecture of sleep. Therefore, we aimed to examine the extent to which daytime pain sensitivity, measured using quantitative sensory testing (QST), is associated with objective sleep parameters the following night, including sleep architecture and power spectral density, in women with TMD.

METHODS

144 females with myalgia and arthralgia by examination using the Diagnostic criteria for TMD completed a comprehensive QST battery consisting of General Pain Sensitivity, Central Sensitization Index, and Masseter Pressure Pain Threshold assessments. Polysomnography was collected the same night to measure sleep architecture and calculate relative power in delta, theta, alpha, sigma, and beta power bands.

RESULTS

Central Sensitization (B = -3.069, P = .009), General Pain Sensitivity Indices (B = -3.069, P = .007), and Masseter Pain Pressure Threshold (B = 0.030, P = .008) were significantly associated with lower REM% both before and after controlling for covariates. Pain sensitivity measures were not significantly associated with relative power in any of the spectral bands nor with any other sleep architectural stages.

CONCLUSIONS

Our findings demonstrate that higher generalized pain sensitivity, masseter pain pressure threshold, as well as central sensitization were associated with a lower percentage of REM in participants with myofascial pain and arthralgia of the masticatory system. These findings provide an important step toward understanding the mechanistic underpinnings of how chronic pain interacts with sleep physiology.

Significance of radiographic temporomandibular degenerative joint disease findings

The field of orthodontics has seen a recent increase in the number of patients over the age of 50 seeking treatment and also an increase in the use of cone beam technology. Similar to other joints in the body, the temporomandibular joint (TMJ) is associated with age-related degeneration. However, unlike other joints, degeneration of the TMJ is rarely symptomatic and when there is pain, it is usually self-limiting. In this article, we will review: a) the incidence and prevalence of TMJ degenerative diseases, b) similarities and differences of TMJ vs knee degenerative diseases, and c) current treatment recommendations for TMJ degenerative diseases. In the vast majority of people, radiographic evidence of TMJ degeneration is an incidental finding. Future longitudinal research is needed to follow the natural course of TMJ degenerative patients.

Association between clinical symptoms and MRI image findings in symptomatic temporomandibular joint (TMJ) disease: A systematic review

To evaluate the association between clinical signs and symptoms of temporomandibular joint (TMJ) and magnetic resonance image (MRI) findings in patients with temporomandibular disorders (TMD). Relevant articles on humans over 18 years of age were obtained from five databases (Ovid MEDLINE, PubMed, Scopus, Web of Science, and Google Scholar) up to August 2022. Risk of bias assessment was completed using the Joanna Briggs Institute critical appraisal tools. The GRADEpro (Grading of Recommendations, Assessment, Development, and Evaluation) instrument was applied to assess the level of evidence across studies in a GRADE Summary of Findings table. In total, 22 studies were included in this systematic review. Of these, 11 studies highlighted that joint pain was positively associated with particular MRI findings: joint effusion, bone marrow edema, disk displacement with/without reduction, and condylar erosion. Masticatory muscle pain was found to have a strong positive correlation with disk displacement in four studies. Five studies found no significant association between MRI findings and masticatory muscle pain. Range of motion and MRI findings were examined in six studies. Limited mouth opening was found to be correlated with disk displacement in five studies. Of the 11 studies evaluating the correlation between joint noise and MRI findings, eight reported a significant association between disk displacement and TMJ noise. The results suggested that patients with joint pain and limited range of motion may benefit from MRI. Patients exhibiting primarily muscle pain are unlikely to benefit clinically from MRI. Future studies with improved quality are warranted.

Bruxism, temporomandibular disorders, and headache-a narrative review of correlations and causalities

ABSTRACT

The co-occurrence of bruxism, temporomandibular disorders (TMDs), and headache is common in patients. However, there is conflicting evidence regarding whether this association is simply a result of their high prevalence or whether there are indeed causal relationships. This review provides an overview of the current state of research while taking into account the controversies surrounding research methods, particularly in definitions and diagnostic standards. Bruxism-defined as repetitive jaw muscle activity during sleep or wakefulness-is not a painful disorder but may-particularly in co-occurrence with TMD-worsen pre-existing headache. It seems important to differentiate between sleep and awake bruxism because of different impact on pathophysiological processes in different primary headache disorders such as migraine and tension-type headache. Temporomandibular disorder is a heterogenous entity with both myofascial and arthrogenous types of pain in addition to nonpainful disorders. Research suggests a correlation between TMD pain and migraine, as well as between awake bruxism and tension-type headache. However, psychosocial factors may act as confounders in these relationships. Determining causality is challenging because of the limited number of experimental and clinical studies conducted on this topic. The main finding is an apparent lack of consensus on the definition and assessment criteria for bruxism. Treatment wise, it is important to differentiate all 3 conditions because treatment of one condition may have an effect on the other 2 without proving causality. For future research, it is crucial to establish greater consistency and applicability in diagnostic procedures and definitions. In addition, more experimental and clinical studies investigating the question of causality are needed.

Prevalence of temporomandibular disorders and their associated factors in Confucian heritage cultures: A systematic review and meta-analysis

BACKGROUND

Temporomandibular disorders (TMDs) may be an 'idiom' of psychological distress in Confucian heritage cultures (CHCs).

OBJECTIVES

This systematic review/meta-analysis estimated the prevalence of TMDs in CHCs and compared the differences in TMD occurrence between time periods and age groups. Additionally, the associated biopsychosocial risk factors were also examined.

METHODS

The study protocol was developed a priori following the PRISMA guidelines and Joanna Briggs Institute systematic review methodology (CRD42021245526). Electronic searches of seven databases were conducted from January 2002 to Dec 2021. Reference lists of identified studies were hand-searched for additional articles. Study selection, quality assessment, and data extraction were done. Meta-analysis was performed using the RevMan 5.4 software.

RESULTS

Forty-eight articles were included in the systematic review. Overall prevalences were: TMDs-15% (95% CI: 15-16%); TMD pain-8% (95% CI: 7-9%); TMJ sounds-24% (95% CI: 21-27%); and TMJ locking-7% (95% CI: 1-13%). While TMD prevalence appeared to have declined from 2002 to 2011 to 2012-2021, the occurrence of TMD pain, TMJ sounds, and locking increased marginally or remained constant. TMD prevalence in children/adolescents was 18% (95% CI: 14-22%) and 17% (95% CI: 16-18%) among adults. Significant associations between TMDs and bruxism/psychological distress/education levels were specified by 73%/90%/88% of the relevant studies.

CONCLUSIONS

TMDs are prevalent in CHCs and a slight increase in TMD pain (2%) and TMJ sounds (8%) were discerned over the past two decades. TMDs are related to a myriad of biopsychosocial variables, particularly psychological distress, and these factors must be addressed within the cultural context of patients.

Effectiveness and safety of hominis placental pharmacopuncture for chronic temporomandibular disorder: A multi-center randomized controlled trial

Background

Hominis placental (HPP) extract has been approved by the Ministry of Food and Drug Safety in Korea for treating chronic liver diseases and postmenopausal syndrome. However, its efficacy and safety for treating chronic temporomandibular disorder (TMD) remains unclear. We aimed to assess the effectiveness and safety of HPP for treating chronic TMD compared with physical therapy (PT).

Methods

This study is a 2-arm parallel, multi-center, randomized controlled trial. We enrolled 82 chronic TMD patients from 2 Korean medicine hospitals between December 2019 and January 2021. We included patients with chronic TMD and randomly assigned them to undergo HPP or PT. The primary outcome was the difference in the scores for temporomandibular joint (TMJ) pain at baseline and week 6. The secondary outcomes were the scores for TMJ pain and bothersomeness, TMJ range of motion, the Korean version of Beck's depression index-Ⅱ, jaw functional limitation scale (JFLS) score, patient global impression of change (PGIC) scores, EuroQoL 5-dimension 5-level score, and short form-12 health survey (SF-12) scores.

Results

Compared with PT, HPP showed significantly superior effects on TMJ pain and bothersomeness, protrusive movement pain, JFLS (verbal, emotional, and global), SF-12, and PGIC scores at week 6 (P < 0.05). Compared with the PT group, the HPP group showed a significantly higher recovery rate (≥50 % reduction in the scores for TMJ pain at the 24-week follow-up).

Conclusion

HPP was more effective than PT managing pain and improving function and quality of life. Our findings demonstrate the effectiveness and safety of HPP for TMD treatment.

Trial registration

This study has been registered at clinicalTrials.gov (NCT04087005), Clinical Research Information Service (CRIS) (KCT0004437), and Ministry of Food and Drug Safety (No. 31886).

Temporomandibular disorders: the most common diagnostic approaches

BACKGROUND

Temporomandibular disorders (TMDs) are a heterogeneous group of conditions involving the temporomandibular joint complex, and surrounding musculature and osseous components. They are a multifactorial disease that can be determined by organic, genetic aspects, oral parafunctional habits, and psychological stress. They have an annual incidence of more than 5% of the population and about 6% to 12% of the population is affected by symptoms. The diagnostic criteria (DC), introduced by Dworkin, is considered the standard system to diagnose this disease in a specific way. Imaging can support the diagnosis of TMD when history and physical examination findings are equivocal. The aim of the study was to evaluate instrumental examinations and therapies, clinicians prefer to use in different cases of TMDs.

METHODS

An anonymized survey, available in two languages (Italian and English), was given to 450 patients, 398 (120 males, 274 females and 4 who did not answer) of different private dental practices were considered, using Google Form (Google LLC, Mountain View, CA, USA) and used an electronic platform, from September 2021 to February 2022. There was no reminder sent to patients to let them feel free to answer.

RESULTS

We performed binary regression for oral bite prescription considering common symptoms and found that the most representative is jaw block (P=0.007, exponential value [EXP]=0.509), followed by TMJ noises (P=0.01, EXP=0.503) and feeling stressed (P=0.04, EXP=1.125) while headache and tinnitus resulted not significant.

CONCLUSIONS

The study highlighted that magnetic resonance imaging (MRI) is the most instrumental examination adopted by the clinicians and the oral splint(bite) is the therapy most widespread nowadays, even if TMDs are a multifactorial disease that is not, probably, only linked to an alteration of dental occlusion.

Temporomandibular disorder and somatic symptoms: Relations to 'fear of missing out' and other negative emotional states

OBJECTIVE

The association between the 'fear of missing out (FOMO)' and physical symptoms has not been widely explored. This study aimed to investigate the relationship between FOMO and other negative emotions with Temporomandibular disorder (TMD) and somatic symptoms in young adults. The correlations between the various physical and emotional variables were also established.

MATERIAL AND METHODS

TMD and somatic symptoms were appraised with the Short-form Fonseca Anamnestic Index, quintessential five TMD symptoms of the Diagnostic Criteria (DC)/TMD, and Patient Health Questionnaire-15. FOMO and other negative emotional states were assessed with the FOMO Scale and Depression, Anxiety, Stress Scales-21 (DASS-21). Data were evaluated using non-parametric tests/correlation and regression analysis (α = 0.05).

RESULTS

While only negative affectivity (total DASS), anxiety, and stress differed significantly between those without and with TMDs, significant variances in FOMO and all DASS-21 constructs were discerned between individuals without and with somatization.  Conclusions: Individuals with orofacial pain and more severe somatic symptoms have higher levels of negative emotions including FOMO. While somatization increased the prospect of TMDs, being female, presence of TMDs, and negative affectivity were risk factors for somatization in young adults.

CLINICAL RELEVANCE

Asian young adults appear to be disposed to somatization, and TMDs may be a form of functional somatic syndromes. Recognition of somatic symptoms and emotional distress, including FOMO, is essential for person-centric TMD care.

Baseline masticatory muscles' performance may predict pain relief in temporomandibular disorders

OBJECTIVES

To compare masticatory muscles' recruitment in patients with temporomandibular disorders and asymptomatic control subjects. To evaluate if the masticatory muscles' recruitment pattern may predict symptoms' improvement after temporomandibular disorders treatment.

MATERIALS AND METHODS

Standardized surface electromyography of anterior temporalis and superficial masseters muscles were recorded and compared at baseline in 26 patients with arthrogenous temporomandibular disorders (study group) and 26 asymptomatic subjects (control group). The study group was treated pharmacologically and by means of five arthrocentesis sessions. Pre-, during-, and post-treatment pain and mandibular function were assessed and compared among timepoints. Clinical improvement in terms of pain and mandibular function was correlated with pre-treatment standardized surface electromyography values.

RESULTS

Temporomandibular disorders patients showed improved maximum mouth opening and pain during and after treatment with arthrocentesis compared to baseline (T-test p < 0.01). Standardized surface electromyography values were significantly different in temporomandibular disorders subjects compared to controls (T-test p < 0.05). Improvement in pain at rest after treatment was inversely correlated with pre-treatment masseters standardized surface electromyography symmetry (R-coefficient 0.3936; p < 0.05).

CONCLUSIONS

Temporomandibular disorders patients showed a different muscular recruitment pattern compared to controls. The lesser the pre-treatment masseters symmetry, the greater the improvement of pain at rest after treatment.

Sleeping and waking-state oral behaviors in TMD patients: their correlates with jaw functional limitation and psychological distress

OBJECTIVES

This study investigated oral behaviors in various temporomandibular disorder (TMD) subtypes, assessing their frequency, extent, and associations with both jaw functional status and psychological distress.

MATERIALS AND METHODS

Anonymized data from consecutive "initial-visit" TMD patients at a university-affiliated oral medicine clinic were obtained. Alongside demographic information, patients completed various questionnaires including the Diagnostic Criteria for TMD (DC/TMD) Symptom Questionnaire, Oral Behavior Checklist (OBC), Jaw Functional Limitation Scale-20 (JFLS-20), Patient Health Questionnaire-9 (PHQ-9), and General Anxiety Disorder Scale-7 (GAD-7). Patients underwent a protocolized clinical examination and received diagnoses of pain-related (PT), intra-articular (IT), or combined (CT) TMD using the DC/TMD diagnostic algorithms. Data were evaluated with Chi-square/non-parametric tests and logistic regression analyses (α = 0.05).

RESULTS

The study comprised 700 patients (mean age 37.4 ± 15.7 years), with 12.6%, 15.1%, and 72.3% diagnosed with PT, IT, and CT, respectively. For all TMD subtypes, oral activities during sleep were more prevalent than those during wakefulness. While variations in total/subscale OBC scores were insignificant, substantial differences were observed in global/subscale JFLS (PT, CT > IT), depression (PT, CT > IT), and anxiety (CT > IT) scores. Near-moderate correlations (rs = 0,36-0.39) were discerned between overall/waking-state non-functional oral behaviors and depression/anxiety. Multivariate analysis indicated that the odds of different TMD subtypes were influenced by sex, age, and jaw functional status.

CONCLUSIONS

For all TMD patients, sleep-related oral activities were more commonly reported than waking-state activities. Factors such as sex, age, and jaw functional limitation are associated with the likelihood of different TMD subtypes.

STATEMENT OF CLINICAL RELEVANCE

Oral behaviors, in themselves, do not predict distinct TMD subtypes, in contrast to factors such as sex, age, and jaw functional status.

Applications of hydrogels in tissue-engineered repairing of temporomandibular joint diseases

Epidemiological studies reveal that symptoms of temporomandibular joint disorders (TMDs) occur in 60-70% of adults. The inflammatory damage caused by TMDs can easily lead to defects in the articular disc, condylar cartilage, subchondral bone and muscle of the temporomandibular joint (TMJ) and cause pain. Despite the availability of various methods for treating TMDs, few existing treatment schemes can achieve permanent recovery. This necessity drives the search for new approaches. Hydrogels, polymers with high water content, have found widespread use in tissue engineering and regeneration due to their excellent biocompatibility and mechanical properties, which resemble those of human tissues. In the context of TMD therapy, numerous experiments have demonstrated that hydrogels show favorable effects in aspects such as articular disc repair, cartilage regeneration, muscle repair, pain relief, and drug delivery. This review aims to summarize the application of hydrogels in the therapy of TMDs based on recent research findings. It also highlights deficiencies in current hydrogel research related to TMD therapy and outlines the broad potential of hydrogel applications in treating TMJ diseases in the future.

Clinical effect of digitalized designed and 3D-printed repositioning splints in the treatment of anterior displacement of temporomandibular joint disc

OBJECTIVE

To compare the treatment effectiveness of digitized and 3D-printed repositioning splints with that of conventional repositioning splints in the treatment of anterior displacement of the temporomandibular joint disc.

METHODS

This retrospective study included 96 patients with disc displacement of the anterior temporomandibular joint. They were treated with either digitally designed and 3D-printed repositioning splints or traditional splints and followed up for at least six months. Changes in signs and symptoms such as pain and mouth opening before and after treatment were recorded to evaluate treatment outcomes.

RESULTS

During the first month of treatment, both the digitally designed and 3D-printed repositioning splint groups (Group B) and the traditional repositioning splint group (Group A) showed significant increases in mouth opening, with increases of 4.93 ± 3.06 mm and 4.07 ± 4.69 mm, respectively, and there was no significant difference between the two groups. Both groups had a significant reduction in visual analog scale (VAS) pain scores, with Group B showing a greater reduction of 1.946 ± 1.113 compared to 1.488 ± 0.978 in Group A (P < 0.05). By the sixth month, Group B's mouth opening further improved to 38.65 ± 3.22 mm (P < 0.05), while Group A's mouth opening did not significantly improve. Regarding pain, Group A's VAS score decreased by 0.463 ± 0.778 after one month, and Group B's score decreased by 0.455 ± 0.715; both groups showed significant reductions, but there was no significant difference between the two groups.

CONCLUSION

Compared with traditional repositioning splints, digitally designed and 3D-printed repositioning splints are more effective at reducing patient pain and improving mouth opening. 3D-printed repositioning splints are an effective treatment method for temporomandibular joint disc displacement and have significant potential for widespread clinical application.

Prevalence of Temporomandibular Disorders (TMD) in Dental Patients at a Specialized Regional Medical Center in Italy

BACKGROUND AND AIM

This study aimed to evaluate the prevalence of temporomandibular disorders (TMDs) in a sample of general dental patients seeking dental treatments in a northeastern Italian university clinic.

MATERIALS AND METHODS

Records of all patients presented for the first time to the dental division of Maggiore Hospital, Italy, between January 1, 2016, and December 31, 2017, were collected. Patients comprised those presenting to the dental clinics for non-TMD complaints, who, upon general examination, were found to have TMD signs and were referred for TMD evaluation. Data were extracted and analyzed, retrospectively. The prevalence of TMDs, age, gender, signs, and symptoms were evaluated.

RESULTS

Out of the 18,774 patients studied, 284 had signs of TMD. Women predominance was evident (73%), and patients aged 45-50 were the most frequent sub-population within the TMD population. Clicking was the most commonly present symptom (26.8%), and arthralgia was most commonly diagnosed among this sample (30.7%). A considerable number of patients suffered from muscular disease (myalgia and myofascial pain with 10.1% and 20.7% of the patients, respectively). Significant associations were found among those with myofascial pain on the one hand and degenerative disease and disc displacement with reduction, on the other hand. Furthermore, disc displacement with reduction on one side was associated with displacement without reduction on the other side.

CONCLUSION

A considerable number of patients presenting with dental complaints may have asymptomatic TMDs. This highlights the importance of systematic screening of dental patients for TMDs as part of general assessment.

Psychological distress and well-being: their association with temporomandibular disorder symptoms

OBJECTIVE

This study investigated the associations between temporomandibular disorder (TMD) symptoms, psychological distress, and well-being.

METHODS

A total of 372 university students were recruited and stratified into no TMD, TMD pain, TMJ sounds, and combined TMD groups. Psychological distress and well-being were assessed with the Depression, Anxiety, and Stress Scale-21 (DASS-21) and Scales of Psychological Well-being-18 (SPWB-18), respectively. Data were appraised with Kruskal-Wallis/Mann-Whitney U tests and logistic regression analysis (α = 0.05).

RESULTS

Significant differences in anxiety, stress, and autonomy scores were observed among the four groups, and psychological distress was mostly negatively correlated to psychological well-being. Multivariate analyses revealed that anxiety was associated with TMD pain, TMJ sounds, and combined TMD, while autonomy was related to TMJ sounds.

CONCLUSION

Participants with TMD symptoms generally experienced more psychological distress and lower autonomy. Anxiety appeared to increase the likelihood of TMD pain and/or TMJ sounds.

Mouth opening, jaw disability, neck disability, pressure pain thresholds, and myofascial trigger points in patients with disc displacement with reduction: A descriptive and comparative study

OBJECTIVE

To assess jaw and neck function, pressure pain threshold (PPT), and the presence of trigger points (TrPs) in disc displacement with reduction (DDWR) subjects compared to healthy subjects.

METHODS

One hundred DDWR subjects and 100 matched controls were studied. Clinical evaluations included demographic data, range of motion, jaw and neck disability, PPT, and muscle TrPs.

RESULTS

DDWR subjects have limited pain-free opening limitation (p < 0.001), jaw and neck disability limitation (p < 0.001), and higher presence of active and latent TrPs limitation (p < 0.001) compared to healthy subjects.

CONCLUSION

DDWR subjects present a limited pain-free mouth opening, higher jaw and neck disability, lower PPT, and major presence of active and latent TrPs compared to healthy subjects. Cervical spine and TMJ evaluation and treatment should be considered in DDWR patients.

The epidemiological profile of temporomandibular joint disorders in the Tunisian population: A cross-sectional study

Objective

This study aimed to explore the prevalence, signs, and symptoms of different types of TMD (Temporomandibular joint disorders) disorders in Tunisian patients.

Methods

A retrospective cross-sectional study was conducted using the clinical records of patients from the Department of Functional Exploration, Pain, and Orofacial Dysfunction of the Dental Clinic of Monastir.

Results

TMD is associated with a female predominance, with a peak prevalence among those aged between 20 and 40 years. Pain and a limited range of motion were significantly more prevalent in women (p = 0.019 and p = 0.012, respectively). Clicking sounds were the most frequent joint noises (38.2 %). Crepitus was more prevalent among older adults (33 %). Of the different types of TMD, disk displacement with reduction was the most prevalent (n = 216, 39 %). Sleep bruxism was more prevalent than awake bruxism (20.7 % VS 9.5 %). Due to the heterogeneous TMD signs and symptoms, patients tend to seek medical attention from various specialties (e.g. neurology and otolaryngology).

Conclusion

The prevalence of different types of TMD, and the different signs and symptoms varied depending on sociodemographic characteristics, such as sex, age and lifestyle. Diagnosis is challenging and TMD may be confused with other orofacial pain conditions.

Diagnostic and screening inventories for temporomandibular disorders: A systematic review

Objective: To evaluate reliable and validated temporomandibular disorder (TMD) diagnostic instruments for use as diagnostic tools in epidemiological surveys.Methods: Two independent reviewers performed searches in the Medline/PubMed, Cochrane Library, and Web of Science databases to identify validation studies of diagnostic and screening instruments for TMD published up to March 2021.Results: Sixteen studies were included for the systematic review. Different TMD instruments were evaluated, such as FAI, RDC/TMD, DC/TMD, Helkimo Index, and AAOP Questionnaire. The instruments differed according to the number of items. Some questionnaires appear to be effective for the initial screening of TMD patients and can be incorporated in clinical practice and epidemiological studies since they are easy and fast to apply.Conclusion: To provide an accurate TMD diagnosis, it is important to use instruments that involve a clinical examination. Authors suggest the development of a new validated diagnostic tool for use in epidemiological surveys.

Accuracy of the Fonseca Anamnestic Index for identifying pain-related and/or intra-articular Temporomandibular Disorders

Objectives: This study established the diagnostic accuracy of the Fonseca Anamnestic Index (FAI) in relation to the Diagnostic Criteria for TMD (DC/TMD) standard.Methods: A total of 866 TMD patients and 57 TMD-free controls were instructed to answer the FAI and DC/TMD Symptom Questionnaire (SQ). Participants were subsequently categorized into no (NT), pain-related (PT), and/or intra-articular (IT) TMDs using the DC/TMD protocolized examination/algorithms. Receiver operating characteristics (ROC) curves, best cut-off points, and accuracy measures were determined.Results:The FAI demonstrated high accuracy for detecting all TMDs, PT, and IT (AUC = 0.96-0.98). The best cut-off points were 22.50 for all TMDs/IT and 27.50 for PT. Sensitivity of the FAI was high (94.23-98.21%), but specificity was moderate (87.72%) for all diagnostic categories.Discussion:The diagnostic accuracy of the FAI for identifying pain-related and intra-articular TMDs was high. FAI scores ≥25 points should be used to screen for TMDs.

Association between oral health-related quality of life and symptoms of temporomandibular disorder among older adults: A cross-sectional study

OBJECTIVE

Evaluate the association between oral health-related quality of life (OHRQoL) and self-reported symptoms of TMD.

METHODS

Representative samples of older adults (≥60 years) were included (n = 569). Both TMD symptoms and OHRQoL were assessed by Fonseca Anamnestic Index (FAI) and Oral Health Impact Profile-14 (OHIP-14), respectively. Prevalence (those answering "frequently" or "always" in at least one question), severity (total means scores), and extent (number of questions answered as "frequently" or "always") of OHRQoL were estimated.

RESULTS

Overall, 33.4% and 9.5% had mild or moderate/severe TMD symptoms. Those with any symptom of TMD had a prevalence ratio (PR) 38% higher for the worst OHRQoL (95% confidence interval [95%CI]:1.04-1.82) compared to those without TMD symptoms. Worst OHRQoL were observed for those with mild (PR:1.35; 95%CI:1.01-1.81) and moderate/severe TMD (PR:1.53; 95%CI:1.04-2.26). Similar results were detected in the severity and extent of OHRQoL.

CONCLUSION

Severity TMD was associated with worse ORHQoL.

Investigation of masticatory muscle thickness and mechanosensitivity of cervical and masticatory muscles in myofascial temporomandibular disorder patients with bruxism: A cross-sectional study

OBJECTIVE

Bruxism is a common problem associated with temporomandibular disorders (TMD). The aim of this study was to compare a patient group with Myofascial TMD and bruxism and a healthy control group in terms of masseter and temporal muscle thickness (clenching and resting), mechanosensitivity of neck and jaw muscles, craniofacial pain, and disability and emotional stress status.

METHODS

The study included 31 patients with myofascial TMD and bruxism (19 females, 12 males) with a mean age of 29.96 ± 8.12 years (range, 18-45 years), and a control group of 31 healthy subjects (19 females, 12 males) with a mean age of 27.58 ± 9.39 years years (range, 18-45 years). Masseter and temporal muscle thicknesses were evaluated with a mobile ultrasound device both at rest and when clenching the jaw. The mechanosensitivity values between the upper trapezius, obliquus capitis inferior, masseter and temporal muscles were measured with a digital algometer device. Craniofacial pain and disability level were evaluated with the Craniofacial Pain and Disability Index (CFPDI), and emotional stress levels with the Perceived Stress Scale-14 (PSS-14).

RESULTS

No difference was determined between the two groups in respect of the clenching and resting ratios of muscle thickness in any muscle (p > 0.05). The mechanosensitivity values in all muscles were lower in the myofascial TMD group than in the healthy group (p < 0.05). The CFPDI and PSS-14 scores were higher in the myofascial TMD group (p < 0.05). There was a moderate positive correlation between CFPDI, PSS-14 and Bruxism Frequency Score (p < 0.05).

CONCLUSION

The difference in mechanosensitivity and CFPDI values between the myofascial TMD patients with bruxism and the healthy control group indicates that the problem in this patient group has effects in the craniocervical and cervical regions. In addition, the correlation between CFPDI, PSS-14 and Bruxism Frequency Score in myofascial TMD patients suggests that this problem may be affected by the interaction of different parameters.

Diagnostic accuracy of MRI-CBCT fused images in assessment of clinically diagnosed internal derangement of the temporomandibular joint

OBJECTIVES

To evaluate the diagnostic accuracy of Fused (MRI)-CBCT images in the assessment of internal derangement of the temporomandibular joint.

METHODS

MRI and CBCT images of the TMJ were evaluated bilaterally in 10 patients with clinically diagnosed internal derangement. Image fusion was performed using Amira 3D Software (version 5.4.3, Thermo Fisher Scientific Inc.).

RESULTS

The AUC index for MRI-CBCT fused images was 0.83, which was significantly different from the null hypothesis value of 0.5. This was confirmed by inter-examiner reliability index of 0.87, which is statistically significant.

CONCLUSION

MRI-CBCT fused images can significantly improve the accuracy and inter-examiner reliability in the evaluation of clinically diagnosed cases with internal derangement.

Mallampati score in patients with temporomandibular joint disorders: A pilot case-control study

OBJECTIVES

Temporomandibular joint disorder (TMD) is defined as any functional abnormalities in different parts of the face and neck. The Mallampati index is an indicator for determining the extent of airway blockage. No study has examined the relationship between TMD and Mallampati score. Most studies have investigated the relationship between temporomandibular joint problems and sleep problems. This pilot study aimed to assess the Mallampati index scores among TMD patients.

MATERIAL AND METHODS

Eighty-four people were divided into the case (based on RDC/TMD) and control groups. Demographic information, neck circumference, tongue size, Mallampati score, and other variables were asked of people. STOP-BANG and Pittsburgh Sleep Quality Index (PSQI) were also completed for each patient. Data were analyzed with Chi-square, Fisher's exact, and Mann-Whitney tests.

RESULTS

The Mallampati and PSQI questionnaire scores in the case group were significantly higher than those in the control group (p < 0.001). The results showed that larger tongue and neck circumference patients had a higher Mallampati score. Pearson correlation coefficient showed that the Mallampati score had a direct and significant relationship with body mass index and PSQI (p < 0.001).

CONCLUSIONS

The results of this study show that Mallampati scores were significantly higher among patients with TMD than among healthy individuals.

Occurrence of Cervical Spine Pain and Its Intensity in Young People with Temporomandibular Disorders

Background: The main aim of this cross-sectional study was to compare the occurrence and severity of cervical spine pain in young adults diagnosed with TMDs with a healthy control group (without TMDs). Methods: The study was conducted from June to July 2023. Inclusion criteria were age (18-30 years), cervical spine pain (for at least 1 month), and consent to participate in the study. The study was conducted based on RDC/TMD protocol, an original questionnaire, and a physiotherapeutic examination focused on detecting TMDs. The cervical pain level was assessed using the Visual Analogue Scale (VAS). Thus, a total of 95 subjects were registered for the trials, 51 people (53.7%) constituted the control group (without TMDs), while 44 (46.3%) people constituted the study group (with TMDs). Results: The mean age of people participating in the study was 22.2 ± 2.2 years in the study group and 22.5 ± 3.1 years in the control group. The largest group was people aged 21-25 (n = 51 people, 53.7%). Patients from the study group more often experienced pain in the stomatognathic system during palpation (both in the muscle, joint, and musculoskeletal groups) and had reduced mobility of the temporomandibular joints in every movement (p < 0.001). People from the study group were also characterized by less mobility of the cervical spine (p < 0.05), apart from extension movement (p > 0.05). The analysis showed that of the 95 people participating in the study, 85.4% reported problems in the cervical spine area (n = 81), of which almost all people in the study group struggled with this problem (n = 43, 97.7%). It was found that cervical spine pain was significantly more common in people with TMDs (p < 0.05, chi2 = 10.118, df = 1, rc = 0.31). The level of pain was significantly higher in people from the study group (p < 0.001, chi2 = 45.765, df = 4, rc = 0.57). Conclusions: Our research has shown that the occurrence of cervical spine pain is more common in the group of young people with temporomandibular disorders (TMDs). In young people, this problem is rarely recognized and properly treated.

The effectiveness of botulinum toxin for temporomandibular disorders: A systematic review and meta-analysis

OBJECTIVE

The current body of research on utilizing botulinum toxin (BTX) to manage temporomandibular disorders (TMDs) has not yet yielded definitive conclusions. The primary objective of this study was to determine the effectiveness of BTX in pain reduction for TMDs compared to placebo and other treatments. The secondary outcomes evaluated were adverse events, maximum mouth opening, bruxism events, and maximum occlusal force.

MATERIALS AND METHODS

A literature search was performed on PubMed, Dimension Publication, Scopus, and Google Scholar. The RoB 2 tool was used for quality assessment. The mean differences in pain scores were estimated to measure the effect of BTX on pain reduction. For adverse events, the risk ratio for the incidence of side effects was calculated.

RESULTS

Two hundred and sixty non-duplicate articles were identified; however, only 14 RCTS were included in this review. The total study population included 395 patients. The overall risk of bias showed a low to moderate quality of evidence. Results from 6 studies were reported only narratively; four studies were used for meta-analysis on pain reduction, and five were used for meta-analysis on adverse events. The control used in the meta-analysis was placebo injections. Results of the meta-analysis for pain reduction were statistically insignificant for the BTX group with mean differences at MD = -1.71 (95% CI, -2.87 to -0.5) at one month, -1.53 (95% CI, -2.80 to -0.27) at three months, and -1.33 (95% CI, -2.74 to 0.77) at six months. This showed that BTX treatment was not significantly better than placebo for a reduction in pain scores at 1, 3, and 6 months. Regarding safety, the placebo group showed a relative risk of 1.34 (95%CI, 0.48-6.78) and 1.17 (95%CI, 0.54-3.88) at 1 and 3 months respectively. However, the risks were not statistically significant. There was also no difference in the effectiveness of BTX compared to placebo and other treatments for maximum mouth opening, bruxism events, and maximum occlusal force.

CONCLUSION

BTX was not associated with better outcomes in terms of pain reduction, adverse events, maximum mouth opening, bruxism events, and maximum occlusal force. More high-quality RCTs are needed to better understand this topic.

Temporomandibular disorder pain in older adolescents-young adults: Interrelationship with somatic burden, mental ill-being, and well-being

OBJECTIVES

The associations of Temporomandibular disorder (TMD) pain with somatic symptoms, mental ill-being/distress, and well-being were explored, along with the mental correlates of TMD (TS) and somatic symptom (SS) burden in older adolescents-young adults.

METHODS

TMD/somatic symptoms were appraised with the five quintessential symptoms (5Ts) of the DC/TMD/Somatic Symptom Scale-8, whereas mental distress/well-being was assessed with the Depression, Anxiety, Stress Scales-21/Scales of Psychological Well-being-18. Data were examined using Chi-square/non-parametric tests and multivariate analyses (α = .05).

RESULTS

Among the 366 participants, 51.4%, 28.1%, 6.8%, and 13.7% had no TMD (NT), TMD pain (TP), TMD dysfunction (TD), and combined TMD (CT) respectively. Though mental distress varied substantially (CT, TP>NT, TD), no significant differences in well-being were discerned. SS burden, but not TS burden, was moderately correlated to distress.

CONCLUSIONS

The prospect of TMD pain was increased by being female, depressed, and anxious but reduced by "positive relations with others" and "self-acceptance".

IncobotulinumtoxinA in refractory temporomandibular disorder due to disk dislocation: A prospective study

INTRODUCTION

Temporomandibular disorders (TMD) may include conditions involving the temporomandibular joint and/or masticatory muscles. Approximately 20 % of patients are refractory to first-line therapies. This study aims to evaluate the effects and safety of incobotulinumtoxinA in the treatment of refractory TMD due to disk dislocation.

MATERIAL AND METHODS

A quasi-experimental one-arm prospective study was conducted. Target population included individuals with a diagnosis of TMD due to disk dislocation. Patients were treated with electromyography or ultrasound guided injection of incobotulinumtoxinA in the masticatory muscles (20 U into each masseter and pterygoideus lateralis). Pain was assessed using the pain numerical rating scale, maximum unassisted mouth opening was measured in mm, and adverse events were registered at baseline, week 4, week 12 and week 24 post-treatment. Statistical analysis used the Wilcoxon test for the comparison of paired samples and the Mann-Whitney U test for independent samples, considering a p-value ≤ 0.05 as significant.

RESULTS

51 patients with 75 painful temporomandibular joints due to disk dislocation (38 with reduction and 37 without) were included. A significant reduction in pain from a pre-treatment mean of 6.08/10 to a post-treatment mean of 2.04/10 (week 4), 3.18/10 (week 12), and 3.65/10 (week 24) was observed (p < 0.001). A significant decrease in maximum unassisted mouth opening from a pre-treatment mean of 36.45 mm to a post-treatment mean of 32.29 mm at week 4 was observed (p < 0.001).

DISCUSSION

Botulinum toxin injection of the masticatory muscles is safe and seems equally effective in reducing pain in patients with refractory TMD due to disk dislocation.

Laser acupuncture to reduce temporomandibular disorder (TMD) symptoms: systematic review and meta-analysis

The application of low-level laser therapy (LLLT) to acupuncture points may produce effects similar to that of needle stimulation in patients with temporomandibular disorders (TMD). This systematic review was conducted according to the Cochrane Collaboration guidelines and aimed to address clinical questions using the following strategy: Patient/Problem, Intervention, Comparison, and Outcome (PICO). A comprehensive literature search was performed upto April 26, 2023, across nine electronic databases (BVS, PubMed, Scopus, Embase, Web of Science, ScienceDirect, Cochrane Library, Latin American and Caribbean Health Sciences Literature (LILACS), and Google Scholar) supplemented with gray literature. The risk of bias in randomized and nonrandomized clinical trials was assessed using two tools: risk-of-bias (RoB) 2 and Risk Of Bias In Non-randomised Studies-of Interventions (ROBINS-I). Meta-analysis involved the extraction of mean and standard deviation values for spontaneous pain and mouth opening levels. Seven studies were included in this review, all of which used LLLT. The applied wavelengths ranged from 690 to 810 nm without significant variations in light emission patterns. LLLT demonstrated a significant reduction in instantaneous pain levels (standard mean difference [SMD] = 3.85; 95% confidence interval [CI] = 2.09, 5.62; p < 0.003) and an improvement in instantaneous mouth opening ability (mean difference [SMD] = -7.15; 95% CI = -11.73, -2.58; p < 0.002), with low certainty of evidence. LLLT may alleviate symptoms in patients with TMD; however, caution should be exercised when interpreting the results because of protocol variations among studies and the limited number of studies included in the meta-analysis.

Age distribution of East Asian TMD patients and age-related differences in DC/TMD axis I findings

OBJECTIVES

The pattern of age distribution in East Asian temporomandibular disorder (TMD) patients and age-related differences in DC/TMD diagnostic subtypes/categories were evaluated.

SUBJECTS AND METHODS

TMD patients from two University-based centers in China and South Korea were enrolled. Axis I physical diagnoses were rendered according to DC/TMD. Patients were categorized into six age groups (15-24, 25-34, 35-44, 45-54, 55-64, and 65-84 years; Groups A-F respectively).

RESULTS

Youths/young adults (Groups A-C) formed 74.1% of TMD patients. TMJ disc displacements (74.9%), arthralgia (49.2%), and degenerative joint disease [DJD] (36.8%) were the most common TMD subtypes. The majority had combined (54.0%) and chronic (58.5%) TMDs. Youths/young adults and middle-aged/old adults had substantially lower frequencies of merely pain-related (6.2-14.5%) and intra-articular (13.8-16.8%) TMDs correspondingly. "Being female" increased the prospects of pain-related/combined TMDs by 96%/49%, respectively.

CONCLUSIONS

East Asian TMD patients comprised mostly of youths/young adults who had an alarmingly high prevalence of TMJ DJD.

Temporomandibular joint disorders in skeletal class II patients referred to orthognathic surgery: A cross-sectional study

OBJECTIVES

The aim of this study was to assess the prevalence of Temporomandibular Disorders (TMD) in subjects with skeletal class II dentofacial deformity referred for orthognathic surgery, as well as to elucidate its association with sociodemographic and psychosocial features.

METHODS

This was a cross-sectional study using the Research Diagnostic Criteria for Temporomandibular Disorders. The sample comprised class II skeletal patients referred to an Oral and Maxillofacial Surgery center in the Brazilian Northeast.

RESULTS

Seventy-three subjects were enrolled and completed the data collection, which consisted of a physical examination according to Axis I of the Research Diagnostic Criteria for Temporomandibular Disorders and facial analysis. Women represented 82.2% of the sample. Among the assessed subjects, 68.5% were already undergoing orthodontic treatment, and the mean overjet of patients was 6.97 mm. The prevalence of TMD in this sample was 46.6%, with muscular disorders being the most common. Patients with an anteroposterior discrepancy greater than 7 mm showed a higher occurrence of TMD (p = 0.017).

CONCLUSION

This study demonstrated a high prevalence of TMD in skeletal class II patients referred for orthognathic surgery, especially in those with a pronounced overjet, being Group I (muscular disorders) and Group III (degenerative disorders) the most prevalent.

Transcutaneous auricular vagus nerve stimulation for the treatment of myoarthropatic symptoms in patients with craniomandibular dysfunction - a protocol for a randomized and controlled pilot trial

BACKGROUND

Temporomandibular disorders (TMD) are a collective term for pain and dysfunction of the masticatory muscles and the temporomandibular joints. The most common types of TMD are pain-related, which may impact the psychological behavior and quality of life. Currently, the most popular methods for the treatment of TMD patients are occlusal splint therapy, often in combination with physical- and/or pharmacotherapy. However, due to the complexity of etiology, the treatment of chronic TMD remains a challenge. Recently, CE-certified systems for non-invasive VNS (transcutaneous auricular vagus nerve stimulation, taVNS) have become available and show positive effects in the treatment of chronic pain conditions, like migraine or fibromyalgia, with which TMD shares similarities. Therefore, it is the main purpose of the study to evaluate the feasibility of daily taVNS against chronic TMD and to assess whether there is an improvement in pain severity, quality of life, and kinetic parameters.

METHODS

This study is designed as a single-blinded, double-arm randomized controlled trial (RCT) in a 1:1 allocation ratio. Twenty adult patients with chronical TMD symptoms will be enrolled and randomized to stimulation or sham group. In the stimulation group, taVNS is performed on the left tragus (25 Hz, pulse width 250 µs, 28 s on/32 s off, 4 h/day). The sham group will receive no stimulation via a non-functional identical-looking electrode. Validated questionnaire data and clinical parameters will be collected at the beginning of the study and after 4 and 8 weeks. The compliance of a daily taVNS of patients with chronical TMD will be evaluated via a smartphone app recording daily stimulation time and average intensity. Additionally, the treatment impact on pain severity and quality of life will be assessed with different questionnaires, and the effect on the mandibular mobility and muscle activity will be analyzed.

DISCUSSION

This is the first clinical trial to assess the feasibility of taVNS in patients with chronic TMD symptoms. If taVNS improves the symptoms of TMD, it will be a significant gain in quality of life for these chronic pain patients. The results of this pilot study will help to determine the feasibility of a large-scale RCT.

TRIAL REGISTRATION

This study has been registered in the DRKS database (DRKS00029724).

Correlates of jaw functional limitation, somatization and psychological distress among different temporomandibular disorder diagnostic subtypes

OBJECTIVES

This study investigated the jaw functional status and severity of somatic/psychological symptoms in different Diagnostic Criteria for temporomandibular disorders (DC/TMD) diagnostic subtypes and established the correlates between jaw functional limitation, somatization, depression and anxiety.

METHODS

Data were accrued from consecutive 'first-visit' patients seeking TMD treatment at a university-based oral medicine/diagnosis clinic. Axis I physical TMD diagnoses were derived using the DC/TMD methodology and patients were categorized into pain-related (PT), intra-articular (IT) and combined (CT) TMD groups. Axis II measures were also administered and included the Jaw Functional Limitation Scale-20 (JFLS-20), Patient Health Questionnaire-15 and 9 (PHQ-15 and PHQ-9) and General Anxiety Disorder Scale-7 (GAD-7). Chi-square/Kruskal-Wallis tests and Spearman's correlation were employed for statistical evaluations (α = .05).

RESULTS

The final dataset consisted of 772 TMD patients (mean age of 37.7 ± 15.9 years; 70.2% females). The prevalence of PT, IT and CT was 11.9%, 15.7% and 72.4%, respectively. Significant differences in functional jaw limitations, somatization, depression (CT, PT > IT) and anxiety (CT > PT, IT) were observed. Moderate-to-severe somatization, depression and anxiety were detected in 12.6%-15.7% of patients. For all three TMD groups, JFLS global scale/subscale scores were weakly associated with somatization, depression and anxiety scores (rs  < 0.4). Moderate-to-strong correlations were noted between somatization, depression and anxiety (rs  = 0.50-0.74).

CONCLUSIONS

Functional jaw limitations were associated with painful TMDs but appear to be unrelated to somatization and psychological distress. Somatization and depression/anxiety were moderately correlated, underscoring the importance of somatic symptom screening when managing TMD patients.

Comparative Evaluation of CBCT and MRI in Temporomandibular Joint (TMJ) Disorders and their Relationship to Periodontal Health

Cone beam computed tomography (CBCT) and magnetic resonance imaging (MRI) are diagnostic tools frequently employed to evaluate temporomandibular joint (TMJ) disorders, yet their comparative efficacy remains a subject of interest. In this study, we conducted a comparative evaluation of CBCT and MRI in diagnosing TMJ disorders and assessing their association with periodontal health. We recruited a sample of 100 patients presenting with TMJ symptoms and divided them into two groups. Group A underwent CBCT imaging, while Group B received MRI scans. Clinical assessments of periodontal health were performed using established periodontal indices. Diagnostic accuracy, sensitivity, specificity, and interobserver agreement were calculated for each imaging modality. In the current study, CBCT demonstrated superior diagnostic accuracy (85%) compared to MRI (72%) in identifying TMJ disorders. Sensitivity and specificity for CBCT were 87% and 83%, respectively, while for MRI, sensitivity was 68%, and specificity was 76%. Interobserver agreement was substantial for CBCT (κ = 0.75) and moderate for MRI (κ = 0.56). In addition, CBCT revealed a significant correlation between TMJ disorders and periodontal health (P < 0.05), while MRI showed a weaker association (P < 0.1). We concluded from this study and suggest that CBCT is a more accurate imaging modality for diagnosing TMJ disorders compared to MRI. Moreover, CBCT provides valuable insights into the relationship between TMJ disorders and periodontal health, highlighting the importance of comprehensive dental assessments.

The "5Ts" screening tool: Enhancements and threshold values for effective TMD identification

OBJECTIVE

This study aimed to enhance the quintessential "five temporomandibular disorder (TMD) symptoms" (5Ts) screener by incorporating frequency options and distinguishing between TMJ and muscle pain. The diagnostic accuracy along with cut-off points for the effective identification of TMDs was also established.

METHODS

Participants, aged ≥18 years, were recruited from a university-based hospital. After completing surveys encompassing demographic data and the enhanced 5Ts (with frequency options [5Ts-F] and differentiation of TMJ/muscle pain [6Ts-F]), protocolized interviews and clinical examinations were performed following DC/TMD. The diagnostic accuracy and best cut-off points were determined with the area under the receiver operating characteristic curves (AUCs).

RESULTS

324 participants were recruited (mean age 30.0 ± 11.4 years). Among these, 86.4% had TMDs. 5Ts exhibited high diagnostic accuracy for detecting all TMDs (AUC = 0.92) with sensitivity/specificity values of 83.9%/88.6%. Both 5Ts-F and 6Ts-F had slightly better accuracy (AUCs = 0.95/0.96), comparable sensitivity, and superior specificity (97.7%) compared to 5Ts. The best cut-off points were 1.5 for 5Ts and 2.5 for 5Ts-F/6Ts-F.

CONCLUSIONS

Although all three TMD screeners presented high diagnostic accuracy, 5Ts-F/6Ts-F had notably improved specificity. 5Ts scores of >1.5 and 5Ts-F/6Ts-F scores of >2.5 are to be applied for screening the presence of TMDs.

Assessment of the Performance of Ultrasonography for Detecting Myofascial Trigger Points

Needle electromyogram (EMG) research has suggested that endplate noise (EPN) is a characteristic of myofascial trigger points (MTrPs). Although several studies have observed MTrPs through ultrasonography, whether they are hyperechoic or hypoechoic in ultrasound images is still controversial. Therefore, this study determined the echogenicity of MTrP ultrasonography. In stage 1, the MTrP of rat masseter muscle was identified through palpation and marked. Needle EMG was performed to detect the presence of EPN. When EPN was detected, ultrasound scans and indwelling needles were used to identify the nodule with a different grayscale relative to that of its surrounding tissue, and the echogenicity of the identified MTrP was determined. In stage 2, these steps were reversed. An ultrasound scan was performed to detect the nodule at the marked site, and an EMG needle was inserted into the nodule to detect EPN. There were 178 recordings in each stage, obtained from 45 rats. The stage 1 results indicate that the MTrPs in ultrasound images were hypoechoic with a 100% sensitivity of assessment. In stage 2, the accuracy and precision of MTrP detection through ultrasonography were 89.9% and 89.2%, respectively. The results indicate that ultrasonography produces highly accurate and precise MTrP detection results.

Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders: A case report and review of literature

BACKGROUND

The relation between orthodontic treatment and temporomandibular disorders (TMDs) is under debate; the management of TMD during orthodontic treatment has always been a challenge. If TMD symptoms occur during orthodontic treatment, an immediate pause of orthodontic adjustments is recommended; the treatment can resume when the symptoms are managed and stabilized.

CASE SUMMARY

This case report presents a patient (26-year-old, female) with angle class I, skeletal class II and TMDs. The treatment was a hybrid of clear aligners, fixed appliances and temporary anchorage devices (TADs). After 3 mo resting and treatment on her TMD, the patient's TMD symptom alleviated, but her anterior occlusion displayed deep overbite. Therefore, the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves. After the levelling, the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion. After careful examination of temporomandibular joints (TMJ) position, the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion. Eventually, the improved facial appearance and relatively stable occlusion were achieved. The 1-year follow-up records showed there was no obvious change in TMJ morphology, and her occlusion was stable.

CONCLUSION

TMD screening and monitoring is of great clinical importance in the TMD susceptible patients. Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases.