Osteoporosis and the risk of temporomandibular disorder in chronic obstructive pulmonary disease

Causal Links Between Bone Diseases and Temporomandibular Disorders

INTRODUCTION AND AIMS

Epidemiological observational studies have explored the link between bone joint-related diseases and temporomandibular disorders (TMD), but inconsistent conclusions have emerged due to various limitations. This study aims to investigate the causal relationship between bone joint-related diseases and TMD using Mendelian randomization (MR).

METHODS

We utilized a two-sample MR design, applying pooled genome-wide association study (GWAS) data from six subtypes of bone and joint diseases and TMD. Primary analysis was conducted using the inverse-variance weighted (IVW) method, complemented by weighted median (WM), weighted mode, and MR-Egger regression to assess causal relationships. Additionally, we performed reverse causality analyses and applied sensitivity analyses, including MR-PRESSO, MR-Egger, Cochran's Q, and leave-one-out methods to evaluate result robustness, explore heterogeneity, and identify potential biases.

RESULTS

MR genetic prediction analyses indicated that bone and joint-related diseases increase the risk of TMD, with specific odds ratios (OR) for ankylosing spondylitis (AS: OR 1.36, 95% CI: 1.04-1.77, P = .026), rheumatoid arthritis (RA: OR 1.08, 95% CI: 1.03-1.13, P = .001), and osteoporosis (OR 1.0751, 95% CI: 1.0047-1.1505, P = .036). Conversely, reverse MR analysis revealed a positive genetic link from TMD to RA (RA: OR 1.12, 95% CI: 1.02-1.23, P = .018). MR-Egger regression showed no influence of horizontal pleiotropy, and MR-PRESSO detected no outliers. The leave-one-out analysis confirmed the results' stability.

CONCLUSIONS

The findings demonstrate a positive, causal association between TMD risk and AS, RA, and osteoporosis. Moreover, TMD patients exhibit an increased risk of developing RA.

CLINICAL RELEVANCE

Understanding these relationships aids in better diagnosis and management of TMD and its association with bone joint diseases, potentially guiding clinical interventions.

Role and mechanism of Actein on condylar bone metabolism in APOE deletion-induced osteoporotic mice

AIMS

To investigate the effects of Actein from Cimicifugae Rhizoma on condylar bone and cartilage in APOE deletion-induced osteoporotic mice, and to preliminarily explore the underlying mechanism.

METHODS

Sixty 8-week-old female mice were used, which underwent APOE-/- and ovariectomy procedures, followed by oral administration of Actein (15 mg/kg) and Atorvastatin Calcium (AC, 3 mg/kg) for eight weeks. Body weight, uterine weight, and systemic indexes related to bone metabolism and lipid metabolism were assessed in each group. Changes in condylar bone histomorphometric parameters were evaluated using Micro-CT. Morphological changes in the condyle were observed with Hematoxylin-Eosin (H&E), Safranin O/Fast Green, and Alcian Blue Hematoxylin/Orange G (ABH/OG) staining, with OARSI pathology scoring performed. Sirius red staining and immunofluorescence were used to determine the expression levels of Collagen I (Col I) and Collagen III (Col III) in bone matrix, and Col II in cartilage matrix. Immunohistochemistry assessed the relative expression levels of ALP and proteins associated with the Wnt/β-catenin/RUNX2 signaling pathway.

RESULTS

APOE-/- exacerbates ovariectomy -induced osteoporosis (OP) in condylar of mice. Actein and AC significantly reversed OP, improved bone mineral density (BMD), increased bone microarchitecture, and restored abnormal calcium and phosphorus metabolism in the blood and urine. Morphologically, APOE-/- and ovariectomy reduced condylar cartilage thickness, disrupted chondrocyte arrangement, chondrocyte cleavage, and clustered aggregation, resembling osteoarthritis (OA)-like changes. Actein and AC partially restored the disrupted chondrocyte arrangement, smoothed chondrocyte cleavage, and up-regulated the levels of chondrocyte matrix (Col II, aggrecan) and bone matrix (Col III, ALP). Actein reversed the OA process, potentially through the Wnt/β-catenin/RUNX2 signaling pathway.

CONCLUSION

APOE-/- and ovariectomy induced OP, leading to OA-like lesions in condylar of mice. Actein promoted cartilage repair and trabecular bone recovery by increasing extracellular matrix synthesis (Col II, Col III, aggrecan), reversing the OA process, possibly through the Wnt/β-catenin/RUNX2 signaling pathway.

Risk factors for temporomandibular disorders: a systematic review of cohort studies

OBJECTIVE

A systematic review was performed to synthesize and identify risk factors involved in TMD onset.

STUDY DESIGN

Electronic searches were conducted in PubMed, Web of Science, Scopus, Embase, PsyInfo and Lilacs databases, as well as in three gray literature databases (Google Scholar, ProQuest and Open grey). The studies were blindly assessed by two reviewers and selected by a pre-defined eligibility criterion. Risk of bias of included studies was assessed using the Joanna Briggs Institute Critical Appraisal Checklist for Cohort Studies. Grading of Recommendations Assessment, Development and Evaluation (GRADE) was evaluated for most related factors.

RESULTS

Twenty-one cohort studies were included. Significant factors were female gender, symptoms of depression and anxiety, perceived stress, sleep quality, symptoms of obstructive sleep apnea and presence of any comorbidity, such as Irritable Bowel Syndrome, lower back pain, headache frequency, tension-type headache, migraine and mixed headache. Moreover, high estrogen and low testosterone levels in utero, greater pain perception, jaw mobility pain, pain during palpation, orofacial anomalies, as well as extrinsic and intrinsic injuries were also significant.

CONCLUSIONS

Several factors seems to be involved in TMD onset, however, more studies with standardized methodology are necessary to confirm these findings.

Effectiveness of double-puncture temporomandibular joint arthrocentesis with viscosupplementation in different categories of severity - a prospective study

This 3-year prospective study evaluated the efficacy of temporomandibular joint (TMJ) arthrocentesis with viscosupplementation in different severity stages based on the Dimitroulis classification (categories 2-4 were included). TMJ arthrocentesis was performed under local anaesthesia, and the protocol consisted of a double-puncture technique with lavage of ≥150 cc Ringer Lactate plus viscosupplementation. Incobotulinum toxin A was administered 10-15 days preoperatively in patients with concomitant masticatory myalgia. The primary outcome was TMJ pain, assessed by visual analogue scale (VAS, 0-10), and the secondary outcomes were the maximum mouth opening (MMO, mm) and myalgia degree (0-3). All outcomes were assessed on the intervention day (T0) and after the procedure (T1) (minimum 1 month and then 3 months, 6 months, 1 year and every year since). A total of 108 patients were enrolled (mean age of 43.1 ± 18.9 years); 86 (80%) were women and 22 (20%) were men. Preoperative pain was 4.02 ± 3.12 (mean ± SD), MMO was 38.10 ± 9.56 (mean ± SD) and myalgia degree was 1.80 ± 1.18 (mean ± SD). After an average of 215.4 days (31-1253 days), a statistically significant improvement of pain (P < 0.0001), MMO (P = 0.005) and myalgia degree (P < 0.0001) was observed. The overall successful outcome of TMJ arthrocentesis with viscosupplementation was 76%. The authors observed increased arthrocentesis effectiveness and success rate with viscosupplementation in Dimitroulis category 2 (88.6%) compared to 3-4 (71.4%). An association was found between arthrocentesis with viscosupplementation failure and painful myalgia (ρ = 0.477; P < 0.0001). Thirteen patients (12%) underwent a second TMJ intervention after finalising the present trial. With a low complication rate, TMJ arthrocentesis with viscosupplementation led to an overall benefit for all the included patients. This study reinforces the important role of minimally invasive TMJ arthrocentesis as a first treatment option, with better results in the early stages compared to more severe stages.

Increased Risk of Temporomandibular Joint Disorder in Osteoporosis Patients: A Longitudinal Study

BACKGROUND

The objective of this study was to investigate the risk of temporomandibular joint disorder (TMD) in patients with osteoporosis.

METHODS

Data from the Korean National Health Insurance Service-Health Screening Cohort from 2002 to 2015 were collected. Participants ≥ 40 years old were enrolled, and the history of osteoporosis was evaluated. The 62,328 osteoporosis patients were matched for age, sex, income, and region of residence with 62,328 control participants. The occurrence of TMD was assessed in both the osteoporosis and control groups during the follow-up period. Stratified Cox proportional hazard analyses for TMD were conducted for the osteoporosis and control groups. The hazard ratios (HRs) of osteoporosis for TMD were further analyzed by age and sex subgroups.

RESULTS

A total of 1.2% (725/61,320) of the osteoporosis patients and 0.6% (339/61,320) of the control participants had TMD (P<0.001). Osteoporosis was associated with an elevated HR of TMD (adjusted HR=1.96, 95% CI=1.72-2.23, P<0.001). Among the age and sex subgroups, the < 60-year-old mal\e group demonstrated an adjusted HR of osteoporosis for TMD as high as 4.47 (95% CI=1.17-17.12, P=0.029). Other age and sex subgroups also showed a higher HR for TMD associated with osteoporosis (adjusted HR=2.30, 95% CI=1.90-2.78, P<0.001 for the ≥ 60-year-old female group).

CONCLUSION

Osteoporosis was related to a higher risk of TMD in the adult population. A prominent association of osteoporosis with TMD was noted in middle-aged men and older women.