Gender differences in temporomandibular disorders in adult populational studies: A systematic review and meta-analysis

Pain Management and Rehabilitation for Central Sensitization in Temporomandibular Disorders: A Comprehensive Review

Temporomandibular disorders (TMD) are a group of musculoskeletal diseases affecting masticatory muscles and temporomandibular joints (TMJ). In this context, the chronic TMD could be considered as a condition with chronic primary orofacial pain, presenting as myofascial TMD pain or TMJ arthralgia. In this context, myogenous TMD may present overlapping features with other disorders, such as fibromyalgia and primary headaches, characterized by chronic primary pain related to dysfunction of the central nervous system (CNS), probably through the central sensitization. This phenomenon could be defined as an amplified response of the CNS to sensory stimuli and peripheral nociceptive, characterized by hyperexcitability in the dorsal horn neurons in the spinal cord, which ascend through the spinothalamic tract. The main objectives of the management of TMD patients are: decreasing pain, increasing TMJ function, and reducing the reflex masticatory muscle spasm/pain. The first-line treatments are physical therapy, pharmacological drugs, occlusal splints, laser therapy, extracorporeal shockwave therapy, transcutaneous electrical nerve stimulation, and oxygen–ozone therapy. Although all these therapeutic approaches were shown to have a positive impact on the central sensitization of TMD pain, there is still no agreement on this topic in the scientific literature. Thus, in this comprehensive review, we aimed at evaluating the evidence on pain management and rehabilitation for the central sensitization in TMD patients.

Temporal changes and gender differences related to orofacial symptoms in two cohorts of 75-year-old Swedish subjects examined in 2007 and 2017: A repeated cross-sectional study

OBJECTIVES

To compare two cohorts of 75-year-old persons, born 10 years apart, in regard to reported symptoms related to temporomandibular disorders (TMD) and orofacial complaints with special reference to gender differences.

MATERIAL AND METHODS

In 2007, a questionnaire comprising questions on social factors, general and oral health, and a series of attitude-related questions was mailed to all individuals born in 1932 living in two Swedish counties (N = 5195), and in 2017 to all born in 1942 (N = 7204). The response rate for the cohort examined in 2007 was 71.9% (n = 3735) and 70.7% (n = 5091) for the cohort examined in 2017. Bivariate statistical analyses were applied.

RESULTS

Reported bruxism and pain from the temporomandibular joint were significantly higher in the 1942 cohort compared to the 1932 cohort, while reports of oral lesions and daytime dry mouth were lower. Women reported problems significantly more frequently in most of the domains investigated in both 2007 and 2017, that is, TMD, burning mouth, sensitive teeth, oral lesions, taste changes, daytime/night-time dry mouth, except bad breath.

CONCLUSIONS

TMD-related symptoms increased while complaints from oral lesions and daytime mouth dryness decreased between 2007 and 2017. Temporal changes were otherwise few, but the findings underline the gender inequalities that exist, to the disadvantage of women. This must be considered when planning for clinical care/dental education to appropriately address the needs of older people.

Comparison of symptoms, signs, gender, and magnetic resonance images of temporomandibular joint disorder patients

OBJECTIVE

To compare patients' complaints, clinician's examination findings, and magnetic resonance imaging (MRI) findings by considering gender.

METHODS

Temporomandibular joint (TMJ) pain, difficulty in mouth opening, masseter tenderness, deviation, clicking sound, bruxism, restriction, normal occlusion and normal mouth opening symptoms, and findings of temporomandibular disorder (TMD) patients who came to the author's outpatient clinic were recorded. These recordings were compared with MRI.

RESULTS

In the study, symptoms, signs, and MRIs of 276 TMD patients were analyzed, including gender. No difference was observed in terms of symptoms, signs, or MRI results for either gender. MRI findings were correlated with restriction and normal mouth opening in both groups (p < 0.05). Normal MRI findings were observed in 52.5% of the MRI results.

CONCLUSION

Except for normal mouth opening and limitation, MRI findings did not provide a significant result. Therefore, careful detection of symptoms and signs rather than MRI helps in diagnosis.

Effects of Contact Sports on Temporomandibular Disorders: An Observational Study

The study investigated the prevalence of temporomandibular disorders in 100 competitive athletes in contact sports, equally grouped by the practiced game: Soccer (SoG), Rugby (RG), American Football (AFG), Boxing (BoG), Basketball (BaG), compared to a randomly control group of 20 non-athletes (CG). Symptoms and signs were examined according to the standardized Diagnostic Criteria for Temporomandibular Disorders through a questionnaire and clinical evaluation. Arthralgia showed significant differences between RG and CG and between AFG and CG (p < 0.05). Study groups reported masticatory muscle pain during function, neck and shoulder pain more frequently than CG, except for BoG. Closing click was significantly more present in study groups than CG, while crepitation was significantly higher only in RG and AFG. The deviation was wider in SoG, RG and AFG compared to CG (p < 0.05). Tukey’s multiple comparisons test showed a statistically significant reduction in right laterotrusion in RG vs. CG (p < 0.05); the comparison showed a decrease in right laterotrusion in RG vs. SoG and BoG (p < 0.05), a decrease in endfeel in RG vs. CG, BaG and AFG (p < 0.05). The data seem to support a relationship between the prevalence of TMD symptoms and signs in competitive athletes in contact sports, especially in RG and AFG compared to CG.

Clinical factors affecting depression in patients with painful temporomandibular disorders during the COVID-19 pandemic

Temporomandibular disorders (TMD) are a multifactorial condition associated with both physical and psychological factors. Stress has been known to trigger or worsens TMD. We aimed to investigate whether the novel coronavirus disease-2019 (COVID-19) pandemic aggravates depression in patients with painful TMD, and the factors that affect their level of depression. We included 112 patients with painful TMD (74 females, 38 males; mean age: 35.90 ± 17.60 years; myalgia [n = 38], arthralgia [n = 43], mixed joint-muscle TMD pain [n = 31]). TMD was diagnosed based on the Diagnostic Criteria for TMD Axis I. Physical pain intensity was recorded using the visual analog scale (VAS); psycho-emotional status (depression: Beck Depression Inventory [BDI], anxiety: Beck Anxiety Inventory [BAI], and generalized stress related to COVID19: Global Assessment of Recent Stress [GARS]) was investigated twice (before [BC] and after COVID-19 [AC]). Additionally, factors affecting BDI-AC were investigated. BDI (p < 0.001), BAI (p < 0.001), GARS (p < 0.001), and VAS (p < 0.01) scores were significantly increased at AC than BC. The depression, anxiety, and stress levels were significantly positively correlated, and the AC and BC values of each factor showed a high correlation. In the mixed TMD group, BDI-AC was positively correlated with VAS-AC (p < 0.001). In the multiple regression analysis, clenching habit was the strongest predictor of an increase in the BDI scores from moderate to severe, followed by psychological distress, muscle stiffness, female sex, BAI-AC, and TMJ sounds. COVID-19 has negatively affected the psycho-emotional state of patients with painful TMD, and several clinical factors, including female sex and clenching habits, have influenced depression.

Negative affectivity and emotions in youths with temporomandibular disorders across cultures

OBJECTIVE

The relationships between temporomandibular disorders (TMDs) and negative affectivity/emotions across cultures and the emotional predictors for TMDs in Southeast Asian youths were investigated.

METHODS

The presence of TMDs and negative affectivity/emotions were determined with the Fonseca Anamnestic Index (FAI) and Depression, Anxiety, Stress Scales-21 (DASS-21). Statistical evaluations were done with non-parametric and logistic regression analyses (α.

RESULTS

The total sample comprised 400 Singaporean and 501 Indonesian youths (mean age 19.30 ± 1.48 years; 65.0% women) of whom 47.0% and 59.3% had mild-to-severe TMDs, respectively. For both cultures, participants with TMDs had significantly greater negative affectivity, depression, anxiety, and stress than those with no TMDs. Indonesian youths also presented higher levels of emotional distress than their Singaporean counterparts. Correlations between FAI and anxiety/stress scores were moderately strong.

CONCLUSION

Cultural variations can influence the expression of TMDs and emotional distress. Being female and anxious increased the risk of TMDs.

Effect of Botulinum Toxin Injection on EMG Activity and Bite Force in Masticatory Muscle Disorder: A Randomized Clinical Trial

Botulinum toxin type A (BoNT-A) is increasingly used in treating masticatory muscle pain disorder; however, safe doses and reinjection intervals still need to be established. The purpose of this randomized clinical trial was to evaluate the degree and duration of the impairment of masticatory muscle performance. Fifty-seven subjects were randomly divided into two groups: one of which received BoNT-A first (n = 28) while the other received saline first (n = 29), with the cross-over being in week 16, and a total follow-up period of 32 weeks. A total dose of 50 U of BoNT-A was injected in the masseter and temporal muscles bilaterally. Electromyographic (EMG) activity and bite forces were assessed. A significant reduction in EMG activity was observed up to week 18 (p ≤ 001), with total recovery at week 33. A significant reduction in maximum bite force was observed up to week 11 (p ≤ 005), with total recovery at week 25. In conclusion, when treating masticatory muscle pain disorder with 50 U of BoNT-A, a reinjection interval of 33 weeks can be considered safe since the recovery of muscle function occurs by that time.

The TMD-7 as a Brief Measure for Assessing Temporomandibular Disorder

OBJECTIVES

 The aim of this cross-sectional prospective study was to determine the internal consistency of the TMD-7, and compare prevalence of TMD symptoms in an adult population.

MATERIALS AND METHODS

 Upon presenting to the orthodontic screening appointment, a total of 440 subjects (316 females and 124 males) were asked to complete the TMD-7 questionnaire. A total of 108 of the participants were later excluded from the study either due to the duplicate or missing responses. The final sample consisted of data from 332 participants (232 females and 100 males), aged between 18 and 64 (mean age: 42.9 ± 9.0) years.

STATISTICAL ANALYSIS

 Cronbach's α statistics were calculated to assess internal consistency. Comparisons between genders, among age categories, and between subjects with versus without prior orthodontic treatment were performed using Wilcoxon ranks sum and Kruskal-Wallis tests. Comparisons for differences in the individual TMD-7 item ratings were performed using Mantel-Haenszel chi-square tests for ordered categorical responses.

RESULTS

 The calculated Cronbach's α for TMD-7 scale was 0.77. No statistically significant differences were found in the TMD-7 scale score or the individual TMD-7 item ratings between age categories (p = 0.993). Females had significantly higher TMD-7 scale score and higher ratings for headache, pain in jaw, pain in neck, pain in forehead, difficulty opening mouth, and difficulty while eating (p < 0.05). No statistically significant differences were found in the TMD-7 scale score or the individual TMD-7 item ratings between subjects with versus without previous orthodontic treatment (p = 0.075).

CONCLUSION

 The TMD-7 tool has good internal consistency and can be used reliably for assessment of TMD symptoms in adults. The use of this tool revealed no significant differences between age groups or between subjects with or without previous orthodontic treatment. However, a significant female gender predisposition for TMD symptoms in the adulthood was determined.

Influence of the COVID-19 pandemic on pain and oral health-related quality of life in women with temporomandibular disorder

Objective:

This study aimed to evaluate and compare pain intensity and Oral Health-related Quality of Life (OHRQoL) in women with temporomandibular disorder (TMD) before (T1) and during (T2) COVID-19 pandemic.

Materials and Methods:

Sample was composed of forty-one female participants with painful TMD, who presented for TMD treatment. Subjects were asked to indicate their pain intensity and to answer the Oral Health Impact Profile-14 (OHIP-14). Participants data were collected twice: T1 (evaluation of medical records fulfilled before COVID-19 pandemic) and T2 (by means of an online form). Socio-demographic data were assessed in T1. Statistical analysis was performed with a significance level of 5% (Wilcoxon, chi-square or Fisher’s exact tests, multiple linear regressions).

Results:

No difference was found in pain intensity (p=0.26) and OHIP-14 global scores (p=0.53). Physical pain (p=0.03) and social disability (p=0.05) domains improved. In T1, subject’s occupation was associated with OHIP-14 global score, physical pain, and physical disability domains. In T2, age was associated with OHIP-14 global scores as well as physical pain, psychological discomfort, and psychological disability domains.

Conclusion:

COVID-19 pandemic did not worsen pain intensity and OHRQoL in women with painful TMD, and it is suggested that socio-demographic characteristics influenced TMD patients coping skills during pandemic.

Advantages of deep learning with convolutional neural network in detecting disc displacement of the temporomandibular joint in magnetic resonance imaging

This study investigated the usefulness of deep learning-based automatic detection of anterior disc displacement (ADD) from magnetic resonance imaging (MRI) of patients with temporomandibular joint disorder (TMD). Sagittal MRI images of 2520 TMJs were collected from 861 men and 399 women (average age 37.33 ± 18.83 years). A deep learning algorithm with a convolutional neural network was developed. Data augmentation and the Adam optimizer were applied to reduce the risk of overfitting the deep-learning model. The prediction performances were compared between the models and human experts based on areas under the curve (AUCs). The fine-tuning model showed excellent prediction performance (AUC = 0.8775) and acceptable accuracy (approximately 77%). Comparing the AUC values of the from-scratch (0.8269) and freeze models (0.5858) showed lower performances of the other models compared to the fine-tuning model. In Grad-CAM visualizations, the fine-tuning scheme focused more on the TMJ disc when judging ADD, and the sparsity was higher than that of the from-scratch scheme (84.69% vs. 55.61%, p < 0.05). The three fine-tuned ensemble models using different data augmentation techniques showed a prediction accuracy of 83%. Moreover, the AUC values of ADD were higher when patients with TMD were divided by age (0.8549–0.9275) and sex (male: 0.8483, female: 0.9276). While the accuracy of the ensemble model was higher than that of human experts, the difference was not significant (p = 0.1987–0.0671). Learning from pre-trained weights allowed the fine-tuning model to outperform the from-scratch model. Another benefit of the fine-tuning model for diagnosing ADD of TMJ in Grad-CAM analysis was the deactivation of unwanted gradient values to provide clearer visualizations compared to the from-scratch model. The Grad-CAM visualizations also agreed with the model learned through important features in the joint disc area. The accuracy was further improved by an ensemble of three fine-tuning models using diversified data. The main benefits of this model were the higher specificity compared to human experts, which may be useful for preventing true negative cases, and the maintenance of its prediction accuracy across sexes and ages, suggesting a generalized prediction.

Gut Bless Your Pain—Roles of the Gut Microbiota, Sleep, and Melatonin in Chronic Orofacial Pain and Depression

Background. Increased attention has been paid to the gut–brain axis recently, but little is known so far regarding how this translates into pain susceptibility. Aim. The aim of this review is to determine whether gastroenterological disorders and sleep disorders (directly or indirectly) contribute to an increased susceptibility to depression and chronic orofacial pain. Method. A search was performed in the U.S. National Library of Medicine (PubMed) database in order to find studies published before 19 December 2021. We used the following terms: gut microbiome, OR sleep quality, OR melatonin, OR GERD, OR IBS, AND: depression OR chronic pain, in different configurations. Only papers in English were selected. Given the large number of papers retrieved in the search, their findings were described and organized narratively. Results. A link exists between sleep disorders and gastroenterological disorders, which, by adversely affecting the psyche and increasing inflammation, disturb the metabolism of tryptophan and cause excessive microglial activation, leading to increased susceptibility to pain sensation and depression. Conclusions. Pain therapists should pay close attention to sleep and gastrointestinal disorders in patients with chronic pain and depression.

Malocclusion Complexity in Patients with Myofascial Pain with or without Mouth-Opening Limitation: A Case-Control Study

Background

This study is aimed at determining the association between myofascial pain with or without mouth-opening limitation and malocclusion complexity.

Methods

A prospective, cross-sectional, case-control study was conducted. The Research Diagnostic Criteria were used to evaluate the presence of myofascial pain, chronic pain, and depression. The Index of Complexity, Outcome, and Need (ICON) was applied to quantify malocclusion complexity. A total of 96 patients with myofascial pain were grouped into two: subjects without mouth-opening limitation (n = 76, group A) and subjects with mouth-opening limitation (group B, n = 20). Both groups were compared with 231 controls (group C). A Chi-squared test and a multinomial logistic regression (p ≤ 0.05) were used to identify associations between the variables.

Results

Statistically significant associations were found between myofascial pain and the variables gender, malocclusion complexity, and depression (p ≤ 0.05). Age was not significantly associated (p = 0.327). Concerning malocclusion complexity, 77.9% of the controls were distributed in the first three ICON levels; however, 76.5% of group A subjects and 90% of group B were in the last three (p < 0.001). The multinomial logistic regression showed a significant association between malocclusion complexity in group A (p < 0.05) and an association between depression and group B (p < 0.05). Group B had the highest grades of chronic pain.

Conclusions

Females had greater risk of myofascial pain without mouth-opening limitation. As the complexity of the malocclusion increases, so do the odds of presenting myofascial pain without mouth-opening limitation. Myofascial pain with mouth-opening limitation frequently coexists with depression and chronic pain.

White Matter Diffusion Properties in Chronic Temporomandibular Disorders: An Exploratory Analysis

Objective

To determine differences in diffusion metrics in key white matter (WM) tracts between women with chronic temporomandibular disorders (TMDs) and age- and sex-matched healthy controls.

Design

Cross sectional study compared diffusion metrics between groups and explored their associations with clinical variables in subjects with TMDs.

Methods

In a total of 33 subjects with TMDs and 33 healthy controls, we performed tractography to obtain diffusion metrics (fractional anisotropy [FA], mean diffusivity [MD], radial diffusivity [RD], and axial diffusivity [AD]) from the cingulum near the cingulate gyrus (CGC), the cingulum near the hippocampus (CGH), the fornix, the anterior limb of the internal capsule (ALIC), the posterior limb of the internal capsule (PLIC), and the uncinate fasciculus (UF). We compared diffusion metrics across groups and explored the relationships between diffusion metrics and clinical measures (pain chronicity and intensity, central sensitization, somatization, depression, orofacial behavior severity, jaw function limitations, disability, and interference due to pain) in subjects with TMDs.

Results

We observed differences in diffusion metrics between groups, primarily in the right side of the brain, with the right CGC having lower FA and the right UF having lower FA and higher MD and RD in subjects with TMDs compared to healthy controls. No clinical measures were consistently associated with diffusion metrics in subjects with TMDs.

Conclusion

The UF showed potential microstructural damage in subjects with TMDs, but further studies are needed to confirm any associations between diffusion changes and clinical measures.

Association of temporomandibular disorders severity with otologic and concomitant pain symptoms in Asian youths

OBJECTIVE

To investigate the presence/severity of TMDs among Asian youths and examine the associations between TMD severity, otologic, and concomitant pain symptoms.

METHODS

Youths (17-24 years old) were recruited from a local polytechnic. The presence/severity of TMDs was determined with the Fonseca Anamnestic Index (FAI), while otologic/concomitant pain symptoms were appraised with the Maciel's Symptoms Checklist (MSC). Demographic, FAI, and MSC data were evaluated using Kruskal Wallis, chi-square, and relevant post-hoc tests (α = 0.05).

RESULTS

Among the participants (n = 200) enrolled, 40.5% had no TMD, whereas mild, moderate, and severe TMD were present in 43.5%, 12.5%, and 3.5%, respectively. Participants with moderate/severe TMDs had significantly more otalgia, tinnitus, vertigo, dizziness, ear pruritus, hearing loss, ear fullness, headache, eye, neck, and back pain than those with no TMDs (p < 0.001).

CONCLUSION

Otologic and concomitant pain symptoms were associated with TMDs and appear to increase with progressive TMD severity.

Viability of the quintessential 5 temporomandibular disorder symptoms as a TMD screener

OBJECTIVE

This study explored the viability of using the 5 temporomandibular disorder (TMD) symptoms (5Ts) of the Diagnostic Criteria for TMDs (DC/TMD) as a TMD screener.

STUDY DESIGN

A total of 1039 adults (≥18 years old) with a mean age of 32.65 ± 12.95 years (77.4% women) from a tertiary dental hospital were enrolled. The 5Ts questionnaire (involving items on TMD/facial pain, headaches, temporomandibular joint noises, and closed- and open-locking) was administered, and TMD diagnoses were derived through clinical interviews and examinations, radiographic investigations, and the DC/TMD diagnostic algorithms and diagnostic tree. Diagnostic accuracy of the 5Ts was assessed using the area under the receiver operating characteristics curve and various measures, including sensitivity, specificity, predictive values, and likelihood ratios.

RESULTS

Among the participants, 80.2% (n = 833) were 5Ts-positive, and 19.8% (n = 206) were 5Ts-negative, whereas 51.3% and 85.7% received at least 1 pain-related and intra-articular DC/TMD diagnosis, respectively. The 5Ts showed high accuracy for detecting all TMDs, pain-related and intra-articular, with area under the receiver operating characteristics curves of 0.98, 1.00, and 0.98, respectively. Sensitivity ranged from 96.1% to 99.2%, whereas specificity was 100.0%.

CONCLUSIONS

The 5Ts demonstrated high diagnostic accuracy for identifying pain-related and/or intra-articular disorders.

Otoneurological assessment and quality of life of individuals with complaints of dizziness and temporomandibular disorders: a case-control study

OBJECTIVES

To evaluate the impact of temporomandibular disorders on the quality of life of patients with dizziness.

METHODS

An observational, case-control study evaluated 60 individuals with dizziness (20 cases and 40 controls), who were matched for gender and age. The individuals underwent to anamnesis, overall physical and otoneurological examination, tonal and vocal audiometry and impedanciometry, video head impulse test and the dizziness handicap inventory questionnaire.

RESULTS

The otoscopy was normal for all patients. There was an association between the presence of temporomandibular disorders and aural fullness (p < 0.01) and otalgia (p < 0.01). Audiometry was normal in 90% of the patients in the case group, with a significant association between temporomandibular disorders and normal audiometry (p < 0.01). The video head impulse test findings were normal in 66% of the patients in the case group and 45% of the control group, and there was no association between having temporomandibular disorders and vestibular alterations at the video head impulse test (p = 0.12). There were significant differences in total dizziness handicap inventory and in the functional and emotional domains (p < 0.01), with higher scores in the control group.

CONCLUSION

Aural fullness and otalgia symptoms are associated with temporomandibular disorders in patients with dizziness, and there is an association between normal complementary audiological tests and temporomandibular disorders. Vestibular alterations are not associated with temporomandibular disorders. However, patients with dizziness and without temporomandibular disorders showed greater quality of life impairment.

LEVEL OF EVIDENCE: 3

Original case-control study.

College Students with Oral Habits Exhibit Worse Psychological Status and Temporomandibular-Related Quality of Life: A Correlational Study

Purpose

To evaluate the relationship between oral habits, psychological status, and temporomandibular-related quality of life among college students.

Materials and Methods

An online questionnaire was sent to college students who were willing to participate in this anonymous survey, which contained questions about the demographic characteristics of the participants, the Patient Health Questionnaire for Depression and Anxiety (PHQ-4), the Fonseca Anamnestic Index (FAI), and the Oral Health Impact Profile for temporomandibular disorders (OHIP-TMDs).

Results

A total of 505 valid questionnaires were collected from 200 males and 305 females (a mean age of 21.81 ± 2.81 years). The prevalence of oral habits in college students was 58% (294/505). Female gender (odds ratio (OR) 1.786) and having oral habits (OR 1.893) were associated with depression and anxiety. Medical students had significantly less depression and anxiety (OR 0.459) than nonmedical students. The possibility of suffering from temporomandibular disorder (TMDs) as evidenced by the OHIP-TMDs score was associated with female gender (OR 1.989) and having oral habits (OR 3.482). Students with oral habits had higher OHIP-TMDs scores.

Conclusion

More than half of the college students surveyed had specific oral habits, with a higher prevalence in women than in men. Having oral habits was related to a worse psychological status, higher risk of TMD, and worse temporomandibular-related quality of life.

Does temporomandibular disorder correlate with menopausal symptoms?

OBJECTIVE

To assess the correlation between menopausal symptoms and pain caused by temporomandibular disorder (TMD) and the impact of sociodemographic factors on the association.

METHODS

In this cross-sectional study, a total of 74 women with TMD symptoms were enrolled and divided into three groups according to the Stages of Reproductive Aging Workshop + 10 (STRAW + 10) criteria: G1 (n = 25, late menopausal transition), G2 (n = 30, early postmenopause), and G3 (n = 19, late postmenopause). Sociodemo-graphic data were collected, along with data on menopausal symptoms (Blatt-Kupperman menopausal index) and TMD-induced pain (craniomandibular index). Statistical analysis was performed using a chi-squared test and linear correlation tests (Spearman and Pearson).

RESULTS

Analysis of the three groups showed that TMD-induced pain was more intense in G1 than in G3 (P = 0.0426, r  = 0.2364, r2 = 0.05589), and menopausal symptoms correlated with the intensity of TMD-induced pain (P = 0.0004, r  = 0.4020). This correlation was more significant during the late menopausal transition (G1: P  = 0.0267, r  = 0.4427, r2 = 0.1960). In G2, women with fewer than 4 years of schooling had a higher total Blatt-Kupperman menopausal index score (17.0 ± 85.0) and craniomandibular index (0.29 ± 0.23) than women with more than 4 years of schooling (P  = 0.02 for both indices).

CONCLUSIONS

Our results suggest that TMD-induced pain and menopausal symptoms are correlated, and more strongly so in the late menopausal transition. Additionally, sociodemographic factors, such as schooling, have a major influence on symptoms in early postmenopause. Performing the TMD evaluation during the climacteric period may be important.

Impact of dentists and equipment in the performing dental imaging examinations: a longitudinal analysis

In this study, we aimed to identify factors associated with performing dental imaging examinations in public health services. Brazilian data at the municipal level (n = 5,564) in two time periods, P0 (2005-2007) and P1 (2014-2016), were collated from health information systems. The increase in the municipal rates of intraoral and extraoral radiographic imaging procedures was the outcome. Changes in the use of clinical procedures and the rates of dentists and equipment were the main predictors. Multiple logistic regression analysis was performed to estimate the adjusted odds ratio (OR). Approximately 35.3% of the Brazilian municipalities increased the dental radiography equipment rate, 9.9% increased the fan-beam computed tomography (CT) equipment rate, and 5.9% increased the magnetic resonance imaging (MRI) equipment rate. In addition, 31.8% increased the periapical/interproximal radiography rate, 10.5% increased the CT rate, and 4.4% increased the MRI rate. Increases in the dental radiography, CT, and MRI rates were associated with higher chances of periapical/interproximal images (OR = 1.90, p < 0.01), face and neck images (OR =1 5.3, p < 0.01), and MR images (OR = 18.1, p < 0.01), respectively. Municipalities that increased the rates of endodontists increased the rates of periapical/interproximal (OR = 2.50, p < 0.01) and occlusal (OR = 1.60, p < 0.01) imaging procedures, and those that increased the rates of radiologists also increased the rates of occlusal (OR = 2.00, p < 0.01) and panoramic (OR = 1.70, p < 0.01) imaging procedures. The implementation of a secondary dental care center, Centro de Especialidades Odontológicas (CEO) was associated with an increase in the chances of performing periapical/interproximal and panoramic radiographic procedures in 1.5 and occlusal radiographic examinations in 2.0. The rates of dentists, equipment, specialized dental centers, and specific dental procedures were associated with the increased use of imaging procedures in dentistry in the Brazilian public health system.

High Pain Intensity is a Risk Factor of Non-Resolving TMD: A Three-Year Follow-Up of a Patient Group in a Norwegian Interdisciplinary Evaluation Program

Purpose

To investigate the outcome of patients with long-term refractory temporomandibular disorders (TMD) three years after a Norwegian interdisciplinary evaluation program with attention to patient satisfaction, function, pain, and psychosocial variables.

Patients and Methods

The study population consisted of 60 long-term refractory TMD patients who were investigated by a Norwegian interdisciplinary team. A questionnaire that covered medical history, function, pain, lifestyle factors, TMD-status and follow-up from their general medical practitioner (GMP) was sent to the patients three years after the evaluation. Questionnaires that assessed function (Mandibular Functional Index Questionnaire [MFIQ] and Roland Morrison Scale [RMS]), pain intensity (General Pain Intensity questionnaire [GPI]) and psychosocial factors (Hospital Anxiety and Depression scale [HADS]); a 2-item version of the Coping Strategies Questionnaire [CSQ]) were included in the package.

Results

Thirty-nine out of 60 TMD patients completed the questionnaires. Improvements in TMD symptoms were reported in 10 patients (26%), were unchanged in 16 patients (41%) and worsened in 13 patients (33%). Only 8 patients (21%) were satisfied with the follow-up of the suggested treatments from their GMP. Significant improvements of symptoms were noted in MFIQ (jaw function), GPI (including pain intensity at maximum and suffering from pain), and CSQ (pain related catastrophizing), in all 39 TMD patients as one group. However, a subgroup analysis showed that the significant improvements were mostly within patients who reported improvement of TMD symptoms. A high pain intensity at baseline was a significant risk factor (OR = 5.79, 95% CI: 1.34, 24.96) for patients who reported worsening of TMD symptoms at follow-up.

Conclusion

High pain intensity at baseline was a significant risk factor for poorer recovery three years after an interdisciplinary evaluation. Our data support the notion that improved coping with TMD pain includes both decreased pain intensity, CSQ and MFIQ scores.

Impact of sports on temporomandibular dysfunction: a comparison of competitive and recreational female athletes as well as female non-athletes

Objectives

The present study was conducted to investigate the correlation between (competitive) sports and the occurrence of temporomandibular dysfunctions (TMD) by comparing the prevalences in competitive, recreational, and non-athletic women.

Materials and methods

A total of 138 women between the ages of 18 and 45 were interviewed about symptoms of TMD by means of a questionnaire. Based on their athletic performance level, the participating women were classified as competitive athletes, recreational athletes, or non-athletes (each group n = 46).

Results

Symptoms of TMD were notably less frequent in competitive female athletes (52.2%) than in recreational female athletes (63.0%) and female non-athletes (60.9%). With increasing training load, the prevalence of TMD decreased in both the competitive and recreational female athlete groups.

Conclusions

Athletic activity in general seems to have a positive effect on the occurrence of TMD. Competitive female athletes appear less likely to suffer from symptoms of TMD than recreational athletes and non-athletes. One possible explanation for this could be the better supervision by qualified trainers and physiotherapists in competitive sports.

Clinical relevance

Patients should be motivated to engage in sports as a protective measure against symptoms of TMD. However, it is important to ensure that they are properly instructed by experienced personnel in order to avoid unphysiological strain and negative consequences.

Masticatory Muscle Thickness and Activity Correlates to Eyeball Length, Intraocular Pressure, Retinal and Choroidal Thickness in Healthy Women versus Women with Myopia

This study aims to examine the correlations between masticatory and neck muscle thickness and activity versus eyeball length, retinal thickness, choroidal thickness, and intraocular pressure in healthy women versus women with myopia. The study group consisted of 21 women aged 24 years and a control group of 19 women (mean age 23 years). For bioelectrical activity analysis within the temporalis anterior, the superficial part of the masseter muscle, the middle part of the sternocleidomastoid muscle, and the anterior belly of the digastric muscle, an eight-channel BioEMG III electromyograph were used. An M-Turbo ultrasound machine was used to analyze masticatory and neck muscle thickness. The eyeball length was examined by IOL Master 500; choroidal and retinal thickness by Optovue Angiovue; and intraocular pressure by Tono-Pen XL. Refractive errors are related to differences in muscle thickness and electromyographic activity. Bioelectrical activity within the temporalis anterior seems to be associated with ocular length, retinal thickness, and choroidal thickness in women with myopia.

Temporomandibular joint (TMJ) disorders prevalence and awareness of appropriate clinical practices, among Al-Madinah community in Saudi Arabia

Background:  Painful temporomandibular joint disorders (TMDs) are of musculoskeletal origin and are considered the most common cause of non-odontogenic pain in the orofacial region.  The purpose of this study was to investigate the prevalence and awareness of temporomandibular joint (TMJ) disorders in Almadinah Almunawwarah community. Methods: An observational cross-sectional study with convenience sampling was conducted. A translated Arabic version of Fonseca's questionnaire was employed. The questionnaire asked about the participant's personal information, if they thought they had TMDs, and who to visit for therapy if necessary. These were followed by 10 items from Fonseca's questionnaire, each with a three-point scale. Results: The questionnaire was completed by 598 people. Females made up 57.1% of the participants. TMDs were present in 61% of the population, with varying degrees of severity. Males (44.3%) were less affected than females (55.7%). The difference, however, was not statistically significant (P = 0.354). Out of the 61% TMDs Positive patients, 74.1% had mild TMDs symptoms, while 20.8% and 5.1%, respectively, had moderate and severe TMDs symptoms (P = 0.05). The severity of the symptoms was unaffected by demographic data (P > 0.05). Only 40% seek care, with 64.6% selecting for a dentist and 24.6% preferring for an orthopaedic specialist (P= 0.008). Conclusions: Participants from Al-Madinah had a greater prevalence of mild TMDs. The majority of the participants had no idea who to go to for treatment. The findings of this study highlight the importance of educational activities to enhance public awareness. Fonseca's Anamnestic Index could also be considered as a useful instrument for early identification and measuring the severity of TMDs in the general population.

Temporomandibular joint (TMJ) disorders prevalence and awareness of appropriate clinical practices, among Al-Madinah community in Saudi Arabia

Background:  Painful temporomandibular joint disorders (TMDs) are of musculoskeletal origin and are considered the most common cause of non-odontogenic pain in the orofacial region.  The purpose of this study was to investigate the prevalence and awareness of temporomandibular joint (TMJ) disorders in Almadinah Almunawwarah community. Methods: An observational cross-sectional study with convenience sampling was conducted. A modified version of Fonseca's questionnaire was employed. The questionnaire asked about the participant's personal information, if they thought they had TMDs, and who to visit for therapy if necessary. These were followed by 10 items from Fonseca's questionnaire, each with a three-point scale. Results: The questionnaire was completed by 598 people. Females made up 57.1% of the participants. TMDs were present in 61% of the population, with varying degrees of severity. Males (44.3%) were less affected than females (55.7%). The difference, however, was not statistically significant (P = 0.354). Out of the 61% TMDs Positive patients, 74.1% had mild TMDs symptoms, while 20.8% and 5.1%, respectively, had moderate and severe TMDs symptoms (P = 0.05). The severity of the symptoms was unaffected by demographic data (P > 0.05). Only 40% seek care, with 64.6% selecting for a dentist and 24.6% preferring for an orthopaedic specialist (P= 0.008). Conclusions: Participants from Al-Madinah had a greater prevalence of mild TMDs. The majority of the participants had no idea who to go to for treatment. The findings of this study highlight the importance of educational activities to enhance public awareness. Fonseca's Anamnestic Index could also be considered as a useful instrument for early identification and measuring the severity of TMDs in the general population.

Psychometric properties of the Malay Fonseca Anamnestic Index for temporomandibular disorders

OBJECTIVE

This study translated/cross-culturally adapted the Fonseca Anamnestic Index (FAI) for temporomandibular disorders (TMDs) into Malay and psychometrically tested the Malay-FAI (FAI-M).

METHODS

The FAI-M was created according to international guidelines. Internal consistency/test-retest reliability were assessed with Cronbach's alpha/intra-class correlation (ICC) coefficients. Construct and convergent validity were appraised by relating the FAI-M to the Global Oral Health (GOH) questionnaire and Short-form Oral Health Impact Profile (S-OHIP) using Kruskal-Wallis and Spearman's rho correlation (α = 0.05).

RESULTS

Of the 243 participants enrolled, 54.7% (n = 133) had no TMDs, while TMDs were present in 45.3% (n = 110). The FAI-M presented very good internal consistency (α = 0.90) and test-retest reliability (ICC = 0.99). Theoretically predicted FAI-M score patterns matched the GOH categories, and strong correlations were discerned between FAI-M and S-OHIP (rs = 0.71).

CONCLUSION

The FAI-M exhibited good psychometric properties and can be applied in Malay-speaking populations.

Craniofacial Morphology of Orthodontic Patients with and without Temporomandibular Disorders: A Cross-Sectional Study

Purpose

We aimed to explore the relationship between temporomandibular disorders (TMDs) and craniofacial morphology in orthodontic patients.

Methods

Altogether, 262 orthodontic patients were included and divided into two groups according to their Fonseca Anamnestic Index (FAI) scores: a no-TMD group (control group, FAI < 20) and a TMD group (FAI ≥ 20). Cephalometric parameters including cranial, maxillary, mandibular, and dental parameters were traced on cephalograms. Craniofacial morphology was compared between TMD and control groups, followed by subgroup analyses based on TMD severity, gender, age, and temporomandibular joint (TMJ) symptoms.

Results

The prevalence of TMDs was 52.7% among included patients (138/262). The mean age of TMD patients was higher than that of the control group. No significant difference in gender distribution between the groups was observed. The most commonly reported FAI items were misaligned teeth, neck pain, and emotional tension. The Frankfort-mandibular plane angle (FMA) was larger in the TMD patients than in the control group, whereas no significant differences in other parameters were observed. Subgroup analysis based on TMD severity revealed that FMA and anterior facial height of moderate/severe TMD patients were significantly larger than those of mild or no-TMD patients. Among male patients, the anterior cranial base length was smaller, and the anterior facial height was larger in the TMD group. Among female patients, no significant differences in craniofacial morphology between the groups were observed. In juvenile patients, overjet and overbite were smaller in the TMD group. In adult patients, SNA, ANB, FMA, and gonial angle were larger in the TMD group. Within the TMD group, patients with TMJ pain or noises exhibited characteristic craniofacial features compared to patients without these symptoms.

Conclusions

Orthodontic patients with TMDs have specific craniofacial morphology, suggesting a relationship between TMDs and particular craniofacial features in orthodontic patients.

The effect of functional mandibular advancement for adolescent patients with skeletal class II malocclusion on the TMJ: a systematic review and meta-analysis

OBJECTIVES

This study aimed to assess whether functional mandibular advancement (FMA) will cause temporomandibular joint disorders (TMD) or have side effects on temporomandibular joint (TMJ) in adolescent patients.

METHODS

All searched databases, including PubMed, Web of Science, EMBASE, Cochrane Central Register of Controlled Trails and Scopus were searched. Gray literature and unpublished literature was also searched. Randomized controlled trails (RCT) and non-randomized studies of the effects of interventions (NRSI) directly observe the condition of adolescent patients' TMJ after finishing treatment will be considered to include in our study. According to Cochrane Handbook, Cochrane Collaboration risk of bias tool was used to assess the quality of included RCTs, and Risk of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool was used to assess the quality of included NRSIs.

RESULT

Finally 18 researches were evaluated as eligible to include in this study. 5 of the studies were RCTs, 8 were NRSIs and 5 were systematic reviews. The data of RCTs and NRSIs were statistically pooled in meta-analysis. The number of samples under investigated among primary studies was 579 individuals,there were 80 patients who developed temporomandibular symptoms during or after treatment. But all the subjective symptoms disappeared during follow-up time. The statistical outcomes proved that patients received FMA didn't show more tendency to develop temporomandibular symptoms [I2 = 27%, OR = 0.54, 95%CI (0.33,0.87), p = 0.01].

CONCLUSION

(1) TMJ symptoms may occur during the functional oral appliance wearing, but the symptoms will release or disappear after treatment or during the follow-up period. (2) Less convincing evidence indicates that slightly previous TMD and condyle-glenoid fossa relationship will be improved after treatment. (3) There is TMJ disc anterior displacement observed during treatment, but most of them will return to the normal position later. (4) Moderate evidence support that FMA will not have side effects on TMJ of adolescent patients.

[Hippocampus is involved in 17β-estradiol exacerbating experimental occlusal inter- ference-induced chronic masseter hyperalgesia in ovariectomized rats]

OBJECTIVE

To investigate the influence of chronic masseter hyperalgesia induced by 17β-estradiol (E2) and experimental occlusal interference (EOI) on underlying mechanism in hippocampus of ovariectomized (OVX) rats.

METHODS

In the study, 32 OVX rats were randomly divided into 4 groups (8 rats/group): The control group was OVX group, and 0 μg/d E2 (vehicle) injection was started 7 d after OVX without EOI; in the experimental group (1) OVX + E2 group, 80 μg/d E2 injection was started 7 d after OVX without EOI; in the experimental group (2) OVX + EOI group, vehicle injection was started 7 d after OVX and EOI was applied 17 d after OVX; in the experimental group (3) OVX + E2 + EOI group, 80 μg/d E2 injection was started 7 d after OVX and EOI was applied 17 d after OVX. Bilateral masseter muscle mechanical withdrawal thresholds were measured before OVX, 7 days after OVX (before E2 injection), 17 days after OVX (10 days after E2 injection and before EOI) and 24 days after OVX (7 days after EOI). Immunofluorescence staining was used to reveal phospho-extracellular signal regulated kinase 1/2 (p-ERK1/2)-positive neurons in CA3 of hippocampus. The protein expression of p-ERK1/2 in hippocampus was detected using Western Blot.

RESULTS

Compared with the control group [left side: (135.3±8.5) g, right side: (135.4±10.8) g], bilateral masseter muscle mechanical withdrawal thresholds of OVX+E2 group [left side: (113.3±5.6) g, right side: (112.5 ± 5.6) g] and OVX+EOI group [left side: (93.3±5.4) g, right side: 90.8±5.5) g] were decreased (P < 0.01). Bilateral masseter muscle mechanical withdrawal thresholds were significantly lower in OVX+E2+EOI group [left side: (81.2±6.2) g, right side: 79.8±7.7) g] than in the control, OVX+E2 and OVX+EOI groups (P < 0.05). The proportion of p-ERK1/2 positive neurons in the CA3 region of the hippocampus was increased in the control, OVX+E2, OVX+EOI and OVX+E2+EOI groups in turn, and the difference between the groups was statistically significant (P < 0.05). p-ERK1/2 protein expression was increased in the control, OVX+E2 and OVX+EOI groups in turn, but the difference was not statistically significant (P>0.05). p-ERK1/2 expression was significantly higher in OVX+E2+EOI group than in the other three groups (P < 0.05).

CONCLUSION

High concentration of E2 could exacerbated EOI-induced chronic masseter hyperalgesia in ovariectomized rats, and its central mechanism may be related to the upregulation of the phosphorylation of ERK1/2 in hippocampus.

Oral nonsteroidal anti-inflammatory drugs as treatment of joint and muscle pain in temporomandibular disorders: A systematic review

OBJECTIVE

To evaluate pain control in patients with joint and muscle pain in temporomandibular disorder (TMD) diagnosis treated with oral non-steroidal anti-inflammatory drugs (NSAIDs).

METHODS

The systematic research was conducted via Pubmed, Scopus, Web of Science, Google Scholar, and Cochrane databases.

RESULTS

Four full-text randomized-controlled trials (RCTs) were considered eligible. This systematic review included 164 patients whose VAS scores were assessed before and after therapy. In the selected studies, a strong heterogeneity in the diagnosis and in the use of different types and prescriptions of NSAIDs was highlighted. These limitations had to be considered to understand whether a clinical recommendation could be made. Eventually, all patients treated with NSAIDs showed an improvement in pain.

CONCLUSION

The use of oral NSAIDs as the first approach to control joint and muscle pain is sustained by the current scientific literature, but further investigations on this topic are still needed.

Patients' perceptions on temporomandibular disorder treatment with hydrostatic oral splints - a pilot study

Objective

To evaluate temporomandibular disorder (TMD) treatment with a prefabricated, hydrostatic oral splint (HOS) based on self-reported patient’s symptoms using a standardized questionnaire.

Methods

Two hundred fifty-eight questionnaires from patients diagnosed with TMD and subsequently treated with HOS were collected from two independent private practices. Based on patient’s comfort the questionnaire recorded TMD symptoms and symptom regression. Descriptive and comparative statistics was carried out using SPSS.

Results

A total of 221 questionnaires were analyzed. Patients reported TMD symptoms such as pain (93.2%), TMJ clicking (66.1%), headache (25.8%), cervical spine disorders (23.5%), restricted mouth opening (22.6%) and tinnitus (11.8%). For most symptoms, improvement was reported mostly after two weeks, except for tinnitus, where positive effects were usually reported after four weeks.

Conclusion

HOS seem to be effective for immediate treatment of pain and other TMD symptoms. Based on the available data, a treatment period of four weeks can be recommended.

Painful Temporomandibular Disorders, Bruxism and Oral Parafunctions before and during the COVID-19 Pandemic Era: A Sex Comparison among Dental Patients

Aim: To evaluate the effect of the current coronavirus pandemic on the prevalence of bruxism, oral parafunctions and painful Temporo-Mandibular Disorders (TMDs) and to evaluate the influence of the pandemic on both sexes. Methods: This retrospective study included 288 dental patients who underwent complete anamnesis and examination according to the Diagnostic Criteria for TMD. The study evaluated two patient populations according to the date of examination: (a) pre-COVID-19 pandemic era (108 patients); (b) COVID 19 pandemic era, where 180 patients were examined during the pandemic. Results: A significant increase in parafunction activity was found in both men and women (p < 0.001) during the COVID-19 pandemic. Awake bruxism (AB) and sleep bruxism (SB) was more prevalent during the COVID-19 pandemic solely in women (AB-p < 0.001; SB-p = 0.014). Conclusions: Men and women were affected by the ongoing stress due to the COVID-19 pandemic, yet women showed a higher influence as compared to men. The long-term exposure to elevated levels of anxiety and stress may aggravate or trigger stomatognathic detrimental conditions. Dentists should be aware and regularly monitor their patients regarding the possible existence and consequences of bruxism and TMD.

Volumetric analysis of normal condyles and those with disc displacement with reduction in the Indonesian population: A CBCT study

Purpose

Disc displacement can cause resorption of the head of the condyle and affect its volume. This study analysed the volume of normal condyles and those with disc displacement with reduction (DDR) in cone-beam computed tomography (CBCT) scans from the Indonesian population.

Materials and Methods

This study analysed 56 condyles (26 normal and 30 with DDR) from patients who visited the Oral and Maxillofacial Radiology Unit after being referred from the Prosthodontics Unit at Dental Hospital Universitas Padjadjaran from December 2020 to February 2021. Samples were divided into 2 groups (normal and DDR left and right-side condyles) based on the DC/TMD Axis 1 form through the clinical examination results. Both sample groups were exposed to CBCT radiation. The CBCT imaging results in the Digital Imaging and Communications in Medicine format were exported to the open-source ITK-SNAP format to determine condyle volume. Volumetric data from the cortical and trabecular areas of the right or left side condyles were arranged by sex. The independent t-test was used to determine the significance of differences with IBM SPSS version 21.0. Intra- and inter-observer reliability and validity were tested before determining the volume of the condyles.

Results

Normal condyles and DDR condyles showed significant differences in volume (P<0.05). Significant differences were also seen in cortical (P=0.0007) and trabecular (P=0.0045) volumes. There was a significant difference in condylar volume based on sex.

Conclusion

The normal condyle volume was significantly different from the DDR condyle volume in both sexes.

Associations among Orthodontic History, Psychological Status, and Temporomandibular-Related Quality of Life: A Cross-Sectional Study

OBJECTIVES

This cross-sectional study aimed to evaluate the associations among orthodontic history, psychological status, and temporomandibular-related quality of life.

METHODS

A questionnaire was developed and distributed to students in a local college, containing questions about demographic information, the Patient Health Questionnaire-4 (PHQ-4), the Fonseca anamnestic index, and the Oral Health Impact Profile for Temporomandibular Disorders (OHIP-TMD). The respondents were divided into with orthodontic history (OS) group and without OS group. Binary logistic regression and multiple linear regression were performed for statistical analysis.

RESULTS

A total of 531 valid questionnaires were collected, covering 161 participants with OS and 370 participants without OS. No statistically significant differences were observed in the scores of PHQ-4 between the two groups. There was statistical difference in the prevalence of TMD (with OS group, 54.66%; without OS group, 40.81%) and the mean value ( ± standard deviations) of the scores of OHIP-TMD (with OS group, 9.64 ± 12.36; without OS group, 6.64 ± 10.79) (p < 0.05). After adjusting confounding factors, participants with OS have worse temporomandibular-related quality of life and a higher risk of having TMD than the participants without OS.

CONCLUSIONS

Orthodontic history was related with the higher prevalence of TMD and worse temporomandibular-related quality of life, but not related with psychological distress, and the cause-and-effect relationship needs further exploration.

Long-term efficacy and patient satisfaction of pulsed radiofrequency therapy in temporomandibular disorders: A randomized controlled trial

BACKGROUND

Pulse radiofrequency (PRF) therapy is one of effective physical therapy modalities for treat temporomandibular disorders (TMD). This prospective randomized controlled trial aimed to evaluate the long-term treatment efficacy and patient satisfaction with PRF therapy in TMD.

METHODS

Eighty-six female patients with TMD were randomly assigned to either pulsed radiofrequency or placebo therapy in combination with other conventional treatments once a week for 12 weeks. A final analysis was performed 12 weeks after the completion of treatment. Clinical parameters and patient satisfaction were analyzed at baseline, 4, 8, and 12 weeks of intervention and at 24 weeks from baseline.

RESULTS

Pain intensity, comfortable and maximum mouth opening, and pain on capsule and masticatory muscle palpation were significantly improved after treatment in both groups. Notably, the pulsed radiofrequency group showed a significantly lower pain intensity at the final evaluation performed 3 months after the completion of treatment. Significantly more patients reported subjective pain improvement and satisfaction with treatment following intervention at baseline in the PRF group. Most patients did not report any discomfort following treatment in either group. However, significantly more patients in the PRF group reported a burning sensation with intervention.

CONCLUSION

Long-term regular pulsed radiofrequency therapy was effective in significantly reducing TMD pain, and the effect was long-lasting following treatment completion. Pulsed radiofrequency therapy should be considered as a supportive physical therapy modality for TMD.

Perspectives on Social and Environmental Determinants of Oral Health

Most oral conditions have a multifactorial etiology; that is, they are modulated by biological, social, economic, cultural, and environmental factors. A consistent body of evidence has demonstrated the great burden of dental caries and periodontal disease in individuals from low socioeconomic strata. Oral health habits and access to care are influenced by the social determinants of health. Hence, the delivery of health promotion strategies at the population level has shown a great impact on reducing the prevalence of oral diseases. More recently, a growing discussion about the relationship between the environment, climate change, and oral health has been set in place. Certainly, outlining plans to address oral health inequities is not an easy task. It will demand political will, comprehensive funding of health services, and initiatives to reduce inequalities. This paper sought to give a perspective about the role of social and physical environmental factors on oral health conditions while discussing how the manuscripts published in this Special Issue could increase our knowledge of the topic.

The impact of gender of the examiner on orofacial pain perception and pain reporting among healthy volunteers

Objectives

Pain on palpation of jaw muscles is a commonly used diagnostic criterion when examining patients with orofacial pain. It is not known, however, if pain reports are affected by the gender of the examiner. Our aim was to investigate if pressure pain threshold (PPT), pressure pain tolerance (PTol), and pain intensity assessed over the masseter muscles in healthy individuals are affected by the gender of the examiner.

Materials and methods

Healthy, pain-free individuals were recruited on a voluntary basis. PPT and PTol were assessed using pressure algometry. At the PTol level, participants also rated pain intensity on a 0–10 numeric rating scale. Assessments of PPT and PTol were conducted with six repeated measurements performed twice, separately by one female and one male examiner, on each participant.

Results

In total, 84 participants (43 women; median age 24, IQR 6) were included. With a female examiner, women reported higher pain intensity than men (Mann Whitney U, p = 0.005). In the multivariable analysis, significantly higher PTol was predicted by male examiner. Also, a higher ratio between PTol and reported pain intensity was predicted by male examiner.

Conclusions

The gender of the examiner influences pain reporting and perception in an experimental setting. This effect on pain perception related to gender of the examiner is probably related to normative gender behaviors rather than to biological alterations within the examined individual.

Clinical relevance

In clinical and experimental settings, gender of the examiner may affect not only pain perception but also pain reporting, with potential implications for diagnostics in patients with pain.

Intraarticular injections of platelet rich plasma and plasma rich in growth factors with arthrocenthesis or arthroscopy in the treatment of temporomandibular joint disorders: A systematic review

Intra-articular platelet rich plasma injections [PRP] or platelet rich growth factors [PRGF] injections have been used as therapeutic treatment options for patients with temporomandibular joint disorder [TMD] in recent years. The purpose of this paper is to evaluate the level of the available scientific evidence in the current literature on the benefits of applying PRP or PRGF injections to patients with TMD simultaneously or after arthrocentesis or arthroscopy to reduce post-operative pain and improve temporomandibular joint function. This systematic review was conducted according to PRISMA criteria and an electronic database search was carried out in the PubMed, Scopus and Cochrane databases during May 2021. The patients in the study group were injected with intra-articular PRP or PRGF simultaneously or after arthrocentesis or arthroscopy while the patients in the control group had arthrocentesis or arthroscopy without an intra-articular injection or received an injection of hyaluronic acid or Ringer's lactate solution. Eight randomised controlled clinical trials were selected. The PRP and PRGF intra-articular injections demonstrated significant differences in terms of pain reduction in three studies and improved mandibular function in two. The treatment with PRP or PRGF intra-articular injections demonstrated slightly better clinical results but of little significance in comparison with the control group. Evidence of their effectiveness is crucial to establish them as non-invasive treatments and as an affordable option for treating some types of TMDs. In accordance with Evidence-based dentistry principles, this review has been assigned a C recommendation.

Preclinical models of deep craniofacial nociception and temporomandibular disorder pain

Chronic pain in temporomandibular disorder (TMD) is a common health problem. Cumulating evidence indicates that the etiology of TMD pain is complex with multifactorial experience that could hamper the developments of treatments. Preclinical research is a resource to understand the mechanism for TMD pain, whereas limitations are present as a disease-specific model. It is difficult to incorporate multiple risk factors associated with the etiology that could increase pain responses into a single animal. This article introduces several rodent models which are often employed in the preclinical studies and discusses their validities for TMD pain after the elucidations of the neural mechanisms based on the clinical reports. First, rodent models were classified into two groups with or without inflammation in the deep craniofacial tissues. Next, the characteristics of each model and the procedures to identify deep craniofacial pain were discussed. Emphasis was directed on the findings of the effects of chronic psychological stress, a major risk factor for chronic pain, on the deep craniofacial nociception. Preclinical models have provided clinically relevant information, which could contribute to better understand the basis for TMD pain, while efforts are still required to bridge the gap between animal and human studies.

Oral health-related quality of life of patients with acute and chronic temporomandibular disorder diagnostic subtypes

BACKGROUND

Studies have indicated the negative effects of temporomandibular disorders (TMDs) on oral health-related quality of life (OHRQoL). The authors investigated the OHRQoL of patients with acute and chronic TMD subtypes.

METHODS

The authors recruited a total of 830 patients. They derived TMD diagnoses using the Diagnostic Criteria for TMDs protocol involving symptom history, physical examination, and diagnostic imaging as indicated. The authors categorized patients into acute (≤ 3 months) or chronic (> 3 months) pain-related TMD (PT), nonpainful intra-articular TMD (IT), and combined TMD (CT) groups. They also gathered sociodemographic information and assessed OHRQoL with the Oral Health Impact Profile (OHIP)-TMDs. The authors evaluated data using 2-way analysis of variance and Bonferroni test and multiple regression analysis.

RESULTS

Patients in the chronic PT and CT subgroups had significantly higher mean global OHIP scores than their acute counterparts. The authors observed significant acute-chronic differences in OHIP-TMDs domain scores in 5 and 2 domains for the PT and CT groups, respectively. Patients in the acute IT group had significantly higher functional limitation scores than those in the chronic IT group. The ranking of mean global scores, in descending order was CT, PT, and IT for acute TMDs and PT, CT, and IT for chronic TMDs, with significant differences observed among the 3 TMD subtypes (P < .001).

CONCLUSIONS

Both TMD chronicity and subtypes influenced OHRQoL. Painful TMDs (PT and CT) were associated with significantly poorer OHRQoL than nonpainful TMDs. TMD chronicity appeared to affect OHRQoL only for the painful TMD conditions. Future work on the impact of TMDs on OHRQoL should strive to stratify patients by TMD chronicity and subtypes.

PRACTICAL IMPLICATIONS

TMD chronicity and subtypes influence the impact of TMDs on OHRQoL. Given that chronic painful TMDs impair quality of life, early biopsychosocial intervention of acute TMD pain is important for minimizing chronification and OHRQoL deterioration.

Impact of the COVID-19 Pandemic on Stress, Sleep, and Oral Health in University Students

Background: The COVID-19 pandemic, a disease caused by Sars-CoV-2, has become a worldwide stressor, especially as it represents a new viral infection, which spreads quickly and easily, without prior knowledge about vaccination, and absence, to this moment, of a medication that is totally effective against the disease.

Objective: The aim of this observational study was to provide a general evaluation, through a questionnaire applied to students in the health field of the Federal University of Rio de Janeiro, on the psychological impacts and behavioral changes generated by the COVID-19 pandemic on oral health, especially the triggering or exacerbation of bruxism and temporomandibular disorders (TMD).

Methods: In order to verify the impacts of the pandemic on the health of UFRJ healthcare students, a non-randomized survey was performed with 370 students.

Results: It was found that 72% of the students had their sleep routine altered, 65% had greater difficulty in keeping their spirits up, there was a statistically significant increase in emotional stress, headaches, and daytime teeth clenching.

Conclusion: It was possible to conclude that the outbreak of COVID-19 resulted in psychological, physiological and behavioral impacts on students.

Impact event and orofacial pain amid the COVID-19 pandemic in Brazil: a cross-sectional epidemiological study

Objectives

This study aims to assess the impact of social isolation, due to the Covid-19 pandemic, on mental health, Temporomandibular Disorder (TMD) and orofacial pain in men and women.

Methodology

Individuals living in Brazil answered an online questionnaire on their sociodemographic and behavioral aspects, emotional scale (DASS-21), Impact of Event Scale, and Pain Screener in Temporomandibular Disorders (TMD-Pain Screener) during June 2020. Descriptive statistical analyses and logistic and linear regressions were applied (5% significance).

Results

Overall, 2301 individuals were included, 89.1% practiced social isolation, 72.6% were employed/studying, at least 15% presented severe or extremely severe levels of emotional distress and presence of powerful (34.1%) and severe impact event (15%). During the outbreak, 53.2% perceived feeling worse and 31.8% reported that orofacial pain started or worsened after the pandemic outbreak. Gender was associated with “social class” (P=0.036), “pain/stiffness in the jaw on awakening” (P=0.037), “change of pain during jaw habits” (P=0.034) and “perception of change in the situations mentioned in the TMD-Pain Screener” (P=0.020), “depression” (P=0.012), “anxiety” (P=0.006) and “impact of the event” (P=8.3E-11). Social isolation had a lesser chance to change the routine, to be practiced by the unemployed/not studying, and to be practiced by men (all with P<0.001). Associations were found between social class and all subscales of the DASS-21 and IES, all with P<0.001.

Conclusions

The practice of social isolation has social determinants. High levels of psychological and event impacts were detected. The presence of orofacial pain seemed to increase during the health crisis, and there were gender differences in the response to the COVID-19 pandemic.

COL5A1 RS12722 Is Associated with Temporomandibular Joint Anterior Disc Displacement without Reduction in Polish Caucasians

Numerous reports describe the association between the single-nucleotide polymorphism (SNP) rs12722 and rs13946 in the COL5A1 gene and injuries, such as Achilles tendon pathology, anterior cruciate ligament (ACL) injuries, and tennis elbow. Hence, there were no studies investigating COL5A1 and temporomandibular joint (TMJ) pathology. The aim of this study is to evaluate the relationship between COL5A1 rs12722 and rs13946 SNPs and TMJ articular disc displacement without reduction (ADDwoR). In this case-control study, the study group consisted of 124 Caucasian patients of both sexes. Each patient had a history of ADDwoR no more than 3 months prior. The control group comprised 126 patients with no signs of TMD according to DC/TMD. Genotyping of the selected SNPs was performed by real-time PCR using TaqMan probes. The significance of the differences in the distribution of genotypes was analyzed using Pearson’s chi-square test. Logistic regression modeling was performed to analyze the influence of the 164 investigated SNPs on ADDwoR. The COL5A1 marker rs12722 turned out to be statistically significant (p-value = 0.0119), implying that there is a difference in the frequencies of TMJ ADDwoR. The distribution of rs12722 SNPs in the study group TT(66), CC(27), CT(31) vs. control group TT(45), CC(26), CT(51) indicates that patients with CT had an almost 2.4 times higher likelihood of ADDwoR (OR = 2.41) than those with reference TT (OR = 1), while rs13946 genotypes were shown to be insignificant, with a p-value of 0.1713. The COL5A1 rs12722 polymorphism is a risk factor for ADDwoR in the Polish Caucasian population.

Association of psychological distress and widespread pain with sympatoms of temporomandibular disorders and self-reported bruxism in students

Objectives

The aim of this study was to evaluate the association of psychosocial distress and widespread pain with self‐reported symptoms of temporomandibular disorders (TMD) and bruxism, in two cross‐sectional surveys in 2012 and 2016, and whether there are temporal changes in the magnitude of associations.

Materials and methods

The data were gathered from Finnish university students in 2012 and 2016. TMD symptoms were assessed with three validated questions and bruxism with one frequently used question. Psychosocial distress was assessed with the General Health Questionnaire‐12 (GHQ‐12), and widespread pain with questions of pain in the extremities, the neck or upper back, and lower back. The associations of GHQ‐12, widespread pain and background variables with TMD symptoms and bruxism were analyzed with chi‐square tests, t‐test and binary logistic regression models stratified by gender, and adjusted for age‐group, self‐reported general health/wellbeing and presence of widespread pain.

Results

Higher GHQ‐12 score and presence of widespread pain were significantly associated with TMD symptoms in both genders at both time points. The association of higher GHQ‐12 score with sleep bruxism and awake bruxism were inconsistent. In the adjusted model higher GHQ‐12 score and widespread pain were significantly related to TMD pain symptoms in both genders at both time points, and to bruxism in 2012. Between the two time points a greater variability in these associations was seen in men than in women.

Conclusions

Psychological distress and widespread pain are significant determinants in perceived TMD pain and bruxism among students. No significant temporal alterations were observed.

Disturbed sleep may be a core risk factor for jaw functional limitation in patients with painful temporomandibular disorders

BACKGROUND

Pain related to temporomandibular disorder (TMD) usually affects jaw function. In patients with TMD, little is known about the biopsychosocial relevance to jaw functional limitations.

OBJECTIVE

This study explored the impact of biopsychosocial risk factors on jaw functional limitation in patients with painful TMD.

METHODS

A comprehensive set of patient-reported outcomes (PROs), consisting of pain severity (Brief Pain Inventory), psychological stress (Symptom Checklist-90-Revised), catastrophising thought (Pain Catastrophizing Scale), kinesiophobia (Tampa Scale for Kinesiophobia-TMD), sleep quality (Pittsburgh Sleep Quality Index) and jaw functional limitation (Jaw Functional Limitation Scale-20), were administered, and clinical examinations were performed in patients with TMD.

RESULTS

This study included the data obtained from 131 patients with painful TMD. In the logistic regression analysis, biomedical factors (age, sex, pain duration and TMD phenotype) were not associated with jaw functional limitation. Correlations were higher in the order of sleep quality (ρ = 0.946), pain severity (ρ = 0.582), pain catastrophising (ρ = 0.535), kinesiophobia (ρ = 0.486) and emotional distress (ρ = 0.268). Multiple regression analysis demonstrated three predictors, including pain severity (p = .001), kinesiophobia (p = .023) and sleep quality (p < .001) for jaw functional limitation. In the mediation analysis, the indirect effect of pain severity on the association between sleep and limitation was significant (p < .0001).

CONCLUSION

Jaw functional limitation is associated with biopsychosocial factors. In particular, sleep may be a core risk factor for functional limitation in patients with painful TMD.