Sick leave and disability pension among TMD patients with musculoskeletal diseases, mental and behavioural disorders - a SWEREG-TMD population-based cohort study.

BACKGROUND: Temporomandibular disorders (TMD) are associated with musculoskeletal diseases (MSD), mental and behavioural disorders (MBD), and patients with TMD have been shown to have 2-3 times more days of sick leave (SL) and disability pension (DP) than the general population. MSD and MBD are two of the most common causes for SL and DP, and the association between TMD and the influence of comorbidities on the need for SL and DP among TMD patients need further clarification. This study investigates the impact of MSD and MBD comorbidity on SL and DP among TMD patients diagnosed in a hospital setting and/or surgically treated. METHODS: All incident TMD patients diagnosed or treated in a hospital setting between 1998 and 2016 and aged 23-59 were included. A non-exposed comparison cohort was collected from the general population. The cohorts were grouped based on the presence of comorbidity: No comorbidity (Group I); MSD comorbidity (Group II); MBD comorbidity (Group III); and combined MSD and MBD comorbidity (Group IV). Main outcomes were mean annual days of SL and DP, and statistical analysis was conducted using generalized estimated equations. RESULTS: TMD subjects with no comorbidities (Group I) and with MSD/MBD comorbidity (Group II and III) were 2-3 times more often on SL and DP than the corresponding groups from the general population. However, in the group with both MSD and MBD comorbidity (Group IV), the difference between the TMD subjects and the general population was diminishing, suggesting an additive effect. CONCLUSION: TMD patients are more dependent on SL and DP benefits compared to general population and the difference remains even after considering MSD and MBD comorbidity. In individuals with combined MSD and MBD comorbidity, concurrent TMD has less impact on the need for social insurance benefits. The results accentuate the impact TMD has on the patients' impaired ability to return to work and why TMD should be recognized as having a substantial impact on individual and economic suffering as well as on societal costs, with emphasis on the influence of comorbidities on patient suffering.

Prevalence of ongoing or previous SARS-CoV-2 infection among dental personnel - the Swedish experience.

CONCLUSIONS: The seroprevalence of SARS-CoV-2 infection was approximately similar to that in healthcare personnel, and approximately equal compared to that in the general population. MATERIALS AND METHODS: We carried out an observational cohort study from March to June 2020, including 341 employees randomly selected from Public Dental Service in the County of Stockholm. The primary outcome variable was the prevalence of SARS-CoV-2 RNA and/or antibodies against SARS-CoV-2. Throat samples were analysed for SARS-CoV-2 RNA. Venous blood was collected to detect antibodies against SARS-CoV-2 using the Luminex analysis tool (immunoassay) and ELISA. Logistic regression analysis was used to compare the independent groups and calculate the unadjusted odds ratio. OBJECTIVE: To investigate whether personnel in a public dental clinic had a higher frequency of ongoing or previous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection than hospital healthcare workers or the general public in Stockholm during weeks 23-25 in 2020. RESULTS: The mean age of the participants was 50.1 years, and 11.7% were male. The prevalence of SARS-CoV-2 RNA and/or antibodies against SARS-CoV-2 was 12.0% (95% confidence interval 8.8-16.0). Among them, 82.5% reported symptoms and 85.4% were on sick-leave between March and June 2020.

Sick leave and disability pension in a cohort of TMD-patients - The Swedish National Registry Studies for Surgically Treated TMD (SWEREG-TMD).

BACKGROUND: Temporomandibular disorders (TMD) are common and affect approximately 10% of the adult population. TMD is usually associated with headache, pain in the masticatory muscles and/or the temporomandibular joint, clicking or crepitations during mandibular movement as well as painful and/or reduced mouth opening. This study aimed to investigate the level TMD-patients use social insurance benefits before and after their first time of diagnosis or first surgical event, compared to the general population. Furthermore, the aim was to investigate the differences in the use of social insurance benefits between surgically and non-surgically treated TMD-patients that were diagnosed in a hospital setting. METHODS: All Swedish citizens aged 23-59 diagnosed with TMD in a hospital setting and/or surgically treated for the condition during 1998-2016 were identified via the Swedish National Board of Health and Welfare. A non-exposed comparison cohort was collected via the Total Population Registry. Outcome and sociodemographic data were collected via Statistics Sweden. Main outcome was annual net days on sick leave and disability pension five years before (-T5) and five years after (T5) diagnosis and/or surgical treatment (T0). Regression analysis was conducted with generalized estimated equations. RESULTS: The study included 219 255 individuals (73% female) - 19 934 in the exposed cohort and 199 321 in the comparison cohort. The exposed group was classified into three subgroups: non-surgical, surgically treated once, and surgically treated twice or more. The mean annual net days of sick leave and disability pension combined during the ten-year follow-up was 61 days in the non-surgical group, 76 days in the surgically treated once group, and 104 days in the surgically treated twice or more subgroup. The corresponding number for the non-exposed comparison cohort was 32 days. CONCLUSION: Patients diagnosed with TMD in a hospital setting are 2-3 times more dependent on the use of social benefits than the general population. The reliance on sick leave and disability pension is seen as early as five years before diagnosis, and the reliance remains after surgical treatment. The reliance is stronger in patients with several surgical interventions. These findings indicate that patients diagnosed with TMD constitute a patient group with a high burden of health issues causing long-term dependence on social security benefits.

Experimental pain and fatigue induced by excessive chewing.

BACKGROUND: The study was aiming to optimize excessive gum chewing as an experimental model to induce jaw muscle pain and fatigue similar to those in painful TMDs with durations that would allow immediate investigations of jaw-motor function. Further, if any sex differences would be detected in the expression of pain. METHODS: This randomized, double blinded study included 31 healthy participants of both sexes. A standardized chewing protocol of either 40- or 60-min of chewing was used with a wash-out period of 1 week. Subjective fatigue, pain characteristics and functional measures were assessed. For statistical analyses, Wilcoxon Signed Rank test, Mann-Whitney Rank Sum test and Friedman's ANOVA with Tukey post-hoc test were used. RESULTS: High subjective fatigue scores that lasted up to 20 min after the end of the trial were significantly induced both in the 40- and 60-min chewing trials (P <  0.001*). Significant but mild pain was induced only in the 60-min trial (P = 0.004*) and only in men (P = 0.04*). Also, the induced pain area was significantly bigger in the 60-min trial (P = 0.009*). However, this increase in pain and pain area did not last to the first 10-min follow-up. There were no significant differences neither between the 40- and 60-min chewing trials, except regarding the pain area (P = 0.008*), nor between the sexes. CONCLUSION: Taken together, excessive chewing in its current form does not seem to be a proper pain experimental model. The model needs further adjustments in order to mimic TMD-pain especially in women and to prolong the pain duration.

Repeated tender point injections of granisetron alleviate chronic myofascial pain--a randomized, controlled, double-blinded trial.

BACKGROUND: Serotonin (5-HT) mediates pain by peripheral 5-HT3-receptors. Results from a few studies indicate that intramuscular injections of 5-HT3-antagonists may reduce musculoskeletal pain. The aim of this study was to investigate if repeated intramuscular tender-point injections of the 5-HT3-antagonist granisetron alleviate pain in patients with myofascial temporomandibular disorders (M-TMD). METHODS: This prospective, randomized, controlled, double blind, parallel-arm trial (RCT) was carried out during at two centers in Stockholm, Sweden. The randomization was performed by a researcher who did not participate in data collection with an internet-based application ( www.randomization.com ). 40 patients with a diagnose of M-TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were randomized to receive repeated injections, one week apart, with either granisetron (GRA; 3 mg) or isotonic saline as control (CTR). RESULTS: The median weekly pain intensities decreased significantly at all follow-ups (1-, 2-, 6-months) in the GRA-group (Friedman test; P < 0.05), but not in the CTR-group (Friedman-test; P > 0.075). The numbers needed to treat (NNT) were 4 at the 1- and 6-month follow-ups, and 3.3 at the 2-month follow-up in favor of granisetron. CONCLUSIONS: Repeated intramuscular tender-point injections with granisetron provide a new pharmacological treatment possibility for myofascial pain patients with repeated intramuscular tender-point injections with the serotonin type 3 antagonist granisetron. It showed a clinically relevant pain reducing effect in the temporomandibular region, both in a short- and long-term aspect. TRIAL REGISTRATION: European Clinical Trials Database 2005-006042-41 as well as at Clinical Trials NCT02230371 .

Diseases of the musculoskeletal system and connective tissue in relation to temporomandibular disorders-A SWEREG-TMD nationwide case-control study.

INTRODUCTION: Temporomandibular disorders (TMD) are comprised by a heterogenous group of diagnoses with multifaceted and complex etiologies. Although diseases of the musculoskeletal system and connective tissue (MSD) have been reported as risk factors for developing TMD, no nationwide population-based registry studies have been conducted to investigate this possible link. The aim of this study was to investigate the association between MSD and TMD in a population-based sample using Swedish registry data, and to further investigate the difference in such association between patients diagnosed with TMD in a hospital setting and patients surgically treated for the condition. MATERIALS AND METHODS: Population based case-control study using Swedish nationwide registry data. Data was collected between 1998 and 2016 from 33 315 incident cases and 333 122 controls aged ≥18, matched for sex, age, and living area. Cases were stratified into non-surgical (NS), surgically treated once (ST1) and surgically treated twice or more (ST2). Information on MSD exposure (ICD-10 M00-M99) was collected between 1964 and 2016. Odds ratios were calculated using conditional logistic regression, adjusted for country of birth, educational level, living area, and mental health comorbidity. RESULTS: A significant association between MSD and the development of TMD was found for all diagnostic categories: arthropathies (OR 2.0, CI 1.9-2.0); systemic connective tissue disorders (OR 2.3, CI 2.1-2.4); dorsopathies (OR 2.2, CI 2.1-2.2); soft tissue disorders (OR 2.2, CI 2.2-2.3); osteopathies and chondropathies (OR 1.7, CI 1.6-1.8); and other disorders of the musculoskeletal system and connective tissue (OR 1.9, CI 1.8-2.1). The associations were generally much stronger for TMD requiring surgical treatment. The diagnostic group with the strongest association was inflammatory polyarthropathies, M05-M14 (OR 11.7, CI 8.6-15.9), which was seen in the ST2 group. CONCLUSIONS: Patients with MSD diagnoses have a higher probability of being diagnosed with TMD, in comparison to individuals without MSD. This association is even stronger for TMD that requires surgery. The results are in line with earlier findings, but present new population-based evidence of a possible causal relationship between MSD and TMD, even after adjusting for known confounders. Both dentists and physicians should be aware of this association and be wary of early signs of painful TMD among patients with MSD, to make early referral and timely conservative treatment possible.

The Role of Mental Health and Behavioral Disorders in the Development of Temporomandibular Disorder: A SWEREG-TMD Nationwide Case-Control Study.

Purpose: There is a well-known association between mental and behavioral disorders (MBD) and temporomandibular disorder (TMD), although the association has not been established in population-based samples. This study aimed to investigate this relationship using national population-based registry data. Patients and Methods: This case-control study used prospectively collected data from Swedish national registries to investigate exposure to MBD and the probability of developing TMD in all Swedish citizens with hospital-diagnosed or surgically treated TMD between 1998 and 2016. Odds ratios were calculated using conditional logistic regression adjusted for educational level, living area, country of birth, musculoskeletal comorbidity, and history of orofacial/neck trauma. Results: A statistically significant association between MBD and TMD was found for mood affective disorders (OR 1.4), neurotic, stress-related and somatoform disorders (OR 1.7), behavioral syndromes associated with psychological disturbances and physical factors (OR 1.4), disorders of adult personality and behavior (OR 1.4), disorders of psychological development (OR 1.3), behavioral and emotional disorders with onset usually occurring in childhood and adolescence (OR 1.4), and unspecified mental disorder (OR 1.3). The association was stronger for TMD requiring surgery, with the strongest association in patients with disorders of psychological development (OR 2.9). No significant association was found with schizophrenia, schizotypal and delusional disorders, or mental retardation. Conclusion: The findings indicate an increased probability of TMD among patients with a history of certain MBD diagnoses, and a stronger association with TMD requiring surgery, specifically repeated surgery. This highlights the need for improved preoperative understanding of the impact of MBD on TMD, as TMD and chronic pain itself may have a negative impact on mental health.

Temporomandibular joint pressure pain threshold is systemically modulated in rheumatoid arthritis.

AIMS: To investigate the relative importance of systemic and local inflammatory mediators (serotonin: 5-HT; tumor necrosis factor: TNF; soluble interleukin-1 receptor II: IL-1sRII) in the modulation of temporomandibular joint (TMJ) pressure pain threshold in patients with seropositive or seronegative rheumatoid arthritis (RA) and to investigate to what extent TMJ pressure pain threshold is related to other TMJ pain parameters. METHODS: Sixty patients with seropositive RA for rheumatoid factor and 74 patients with seronegative RA involving the TMJ were investigated regarding synovial fluid and plasma levels of IL-1sRII, 5-HT, and TNF as well as erythrocyte sedimentation rate, C-reactive protein, thrombocyte particle count, and rheumatoid factor in blood. TMJ resting pain, movement pain, tenderness, and palpebral pain reflex to digital palpation and TMJ pressure pain threshold were examined. RESULTS: Statistical analyses indicated that TMJ pressure pain threshold was only correlated to systemic factors. TMJ movement pain was in turn mainly correlated to systemic mediators in the seropositive patients but to local mediators in the seronegative patients where synovial fluid IL-1sRII was positively correlated to TMJ pain on mouth opening. Seropositive patients had higher systemic inflammatory activity but lower TMJ movement pain intensities than seronegative patients. CONCLUSION: The results indicate that TMJ pressure pain threshold is modulated by systemic rather than local inflammatory mediators and suggest that it is unrelated or only weakly related to other TMJ pain entities in RA patients. A rheumatoid factor-dependent systemic modulation, in combination with local factors, seems to account for TMJ pain in RA patients.

Pressure pain thresholds in the craniofacial region of female patients with rheumatoid arthritis.

AIMS: To determine the temporomandibular joint (TMJ) pressure pain threshold (PPT) in female patients with rheumatoid arthritis (RA) and TMJ involvement in comparison with healthy females, in order to determine its clinical usefulness for local pain assessment. METHODS: Forty-two female patients with the diagnosis of RA, 17 of them positive and 25 negative for rheumatoid factor were investigated, as well as 17 healthy females. A pressure algometer was used to assess the PPT over the TMJ and (as a reference) the center of the glabella. The mean of the second and third TMJ PPT was used in the analysis, and the ratio between the TMJ PPT and the PPT of the reference site (PPT ratio) was calculated. Temporomandibular joint resting pain and pain upon maximum voluntary mouth opening was assessed by a visual analog scale on each side. RESULTS: The TMJ PPT (median/10th to 90th percentile) and PPT ratio were significantly lower in the RA patients (148/64 to 220 and 0.63/0.40 to 1.01, respectively) than in the healthy individuals (217/111 to 352 and 0.85/0.51 to 1.25), but the overlap was considerable. CONCLUSION: This study shows that the PPT of the TMJ in RA patients is lower than in healthy individuals and that it can be used for pain assessment. However, the clinical use of the TMJ PPT and PPT ratio measurements alone is limited from a diagnostic point of view.

Tumor necrosis factor-alpha in temporomandibular joint synovial fluid predicts treatment effects on pain by intra-articular glucocorticoid treatment.

The aim of this study was to investigate the influence of tumor necrosis factor-alpha (TNF-alpha) in temporomandibular joint (TMJ) synovial fluid and blood on the treatment effect on TMJ pain by intra-articular injection of glucocorticoid in patients with chronic inflammatory TMJ disorders. High pretreatment level of TNF-alpha in the synovial fluid was associated with a decrease of TNF-alpha and elimination of pain upon maximal mouth opening. Elimination of this TMJ pain was accordingly associated with decrease in synovial fluid level of TNF-alpha. There was also a significant decrease of C-reactive protein and TMJ resting pain after treatment. In conclusion, this study indicates that presence of TNF-alpha in the synovial fluid predicts a treatment effect of intra-articular injection of glucocorticoid on TMJ movement pain in patients with chronic TMJ inflammatory disorders.

Serotonergic mechanisms influence the response to glucocorticoid treatment in TMJ arthritis.

The aims of this study were to investigate the influence of serotonin (5-HT) on the effects of intra-articular injections of glucocorticoid on pain of the temporomandibular joint (TMJ) in patients with inflammatory disorders of the TMJ. The pretreatment synovial fluid 5-HT was negatively, and plasma 5-HT positively, correlated to change in TMJ pain after treatment. The pretreatment plasma 5-HT was positively correlated to change in pressure-pain threshold after treatment. In conclusion, this study shows that local and systemic serotonergic mechanisms partly determine the effect of intra-articular glucocorticoid treatment on TMJ pain in patients with chronic TMJ arthritis of systemic nature, while change in pressure-pain threshold over the TMJ is influenced by systemic serotonergic mechanisms.