A Three-branch Jointed Feature and Topology Decoder guided by game-theoretic interactions for temporomandibular joint segmentation.

Segmentation of the temporomandibular joint (TMJ) disc and condyle from magnetic resonance imaging (MRI) is a crucial task in TMJ internal derangement research. The automatic segmentation of the disc structure presents challenges due to its intricate and variable shapes, low contrast, and unclear boundaries. Existing TMJ segmentation methods often overlook spatial and channel information in features and neglect overall topological considerations, with few studies exploring the interaction between segmentation and topology preservation. To address these challenges, we propose a Three-Branch Jointed Feature and Topology Decoder (TFTD) for the segmentation of TMJ disc and condyle in MRI. This structure effectively preserves the topological information of the disc structure and enhances features. We introduce a cross-dimensional spatial and channel attention mechanism (SCIA) to enhance features. This mechanism captures spatial, channel, and cross-dimensional information of the decoded features, leading to improved segmentation performance. Moreover, we explore the interaction between topology preservation and segmentation from the perspective of game theory. Based on this interaction, we design the Joint Loss Function (JLF) to fully leverage the features of segmentation, topology preservation, and joint interaction branches. Results on the TMJ MRI dataset demonstrate the superior performance of our TFTD compared to existing methods.

Metabolic profiling of synovial fluid in human temporomandibular joint osteoarthritis.

Introduction: Temporomandibular joint (TMJ) osteoarthritis (OA) is a common TMJ degenerative disease with an unclear mechanism. Synovial fluid (SF), an important component of TMJ, contains various proteins and metabolites that may directly contribute to OA. The present study aimed to investigate the influence of SF in TMJOA at the metabolite level. Methods: Untargeted and widely targeted metabolic profiling were employed to identify metabolic changes in SF of 90 patients with different TMJOA grades according to TMJ magnetic resonance imaging. Results: A total 1498 metabolites were detected. Most of the metabolites were amino acids and associated metabolites, benzene and substituted derivatives, and lipids. Among patients with mild, moderate and severe TMJOA, 164 gradually increasing and 176 gradually decreasing metabolites were identified, indicating that biosynthesis of cofactors, choline metabolism, mineral absorption and selenocompound metabolism are closely related to TMJOA grade. Combined metabolomics and clinical examination revealed 37 upregulated metabolites and 16 downregulated metabolites in patients with pain, of which 19 and 26 metabolites were positively and negatively correlated, respectively, with maximum interincisal opening. A model was constructed to diagnose TMJOA grade and nine biomarkers were identified. The identified metabolites are key to exploring the mechanism of TMJOA. Discussion: In the present study, a metabolic profile was constructed and assessed using a much larger number of human SF samples from patients with TMJOA, and a model was established to contribute to the diagnosis of TMJOA grade. The findings expand our knowledge of metabolites in human SF of TMJOA patients, and provide an important basis for further research on the pathogenesis and treatment of TMJOA.

Application of panoramic radiographs in the diagnosis of temporomandibular disorders.

To evaluate the feasibility of temporomandibular disorder (TMD) diagnosis with panoramic radiography, and provide standardized data for artificial intelligence-assisted diagnosis by measuring the differences in the condylar and mandibular ramus heights. A total of 500 panoramic radiographs (219 male and 281 female participants) of healthy individuals were examined. The panoramic machine compatible measurement software, SCANORA 5.2.6, was used to measure the bilateral condylar height and mandibular ramus height, and SPSS 27.0 was used to calculate the left- and right-side differences in condylar height and mandibular ramus height of healthy individuals. Magnetic resonance images of the temporomandibular joint region obtained from 46 outpatients in the Stomatology Department were selected along with their corresponding panoramic radiographs. The left- and right-sided differences were measured and compared with the magnetic resonance imaging results. The measurement data are expressed as mean ±â€…standard deviation (mm). t Tests were used to analyze data from healthy male and healthy female groups. The findings revealed that while there was no significant difference (P > .05) in the height of the condyle between men and women, there was a significant difference (P  < .05) in the height of the mandibular ramus. In healthy population, the difference in height between the left and right condyle was 1.09 ±â€…0.99 mm. The difference in height of mandibular ramus in men was 1.26 ±â€…0.85 mm and that in women was 1.19 ±â€…0.87 mm. For the diagnosis of TMD, the sensitivity of panoramic radiographs was 94.74% (36/38), specificity was 75.00% (6/8), and diagnostic accuracy was 91.30% (42/46). The height of the right and left lateral condyles was not identical in healthy individuals, resulting in a discernible height discrepancy. In addition, the height of the mandibular ramus varied. By considering the left-right lateral height differences identified in this study along with clinical examination, it is possible to employ this metric as a preliminary screening tool for patients with TMD. Further, the use of panoramic radiographs for initial TMD screening is both viable and significant.

MRI of Temporomandibular Joint Disorders: A Comparative Study of 0.55 T and 1.5 T MRI.

OBJECTIVES: Temporomandibular disorders (TMDs) are common and may cause persistent functional limitations and pain. Magnetic resonance imaging (MRI) at 1.5 and 3 T is commonly applied for the evaluation of the temporomandibular joint (TMJ). No evidence is available regarding the feasibility of modern low-field MRI for the assessment of TMDs. The objective of this prospective study was to evaluate the image quality (IQ) of 0.55 T MRI in direct comparison with 1.5 T MRI. MATERIALS AND METHODS: Seventeen patients (34 TMJs) with suspected intraarticular TMDs were enrolled, and both 0.55 and 1.5 T MRI were performed on the same day. Two senior readers independently evaluated the IQ focusing on the conspicuity of disc morphology (DM), disc position (DP), and osseous joint morphology (OJM) for each joint. We analyzed the IQ and degree of artifacts using a 4-point Likert scale (LS) at both field strengths. A fully sufficient IQ was defined as an LS score of ≥3. Nonparametric Wilcoxon test for related samples was used for statistical comparison. RESULTS: The median IQ for the DM and OJM at 0.55 T was inferior to that at 1.5 T (DM: 3 [interquartile range {IQR}, 3-4] vs 4 [IQR, 4-4]; OJM: 3 [IQR, 3-4] vs 4 [IQR 4-4]; each P < 0.001). For DP, the IQ was comparable (4 [IQR 3-4] vs 4 [IQR 4-4]; P > 0.05). A sufficient diagnostic IQ was maintained for the DM, DP, and OJM in 92% of the cases at 0.55 T and 100% at 1.5 T. Minor image artifacts (LS score of ≥3) were more prevalent at 0.55 T (29%) than at 1.5 T (12%). CONCLUSIONS: Magnetic resonance imaging of the TMJ at 0.55 T yields a lower IQ than does MRI at 1.5 T but maintains sufficient diagnostic confidence in the majority of patients. Further improvements are needed for reliable clinical application.

Peri-articular bone formation involving the temporomandibular joint: a narrative summary and Delphi consensus of a new classification system.

Heterotopic ossification (HO) is defined as 'bone where it does not belong'. Given the historical variety of nomenclature and eponyms, there is significant confusion about the etiology, pathogenesis, classification, and treatment of HO related to the temporomandibular joint (TMJ). The existing classifications for TMJ HO have shortcomings: they relate to specific populations, use differing imaging studies and demographic data, do not universally include alloplastic/autologous replacements, are based variously on radiological and/or clinical presentations that cannot always be combined, and were largely developed to assist oral and maxillofacial surgeons in surgical management. These deficiencies make it problematic to compare studies, draw valid conclusions, and pursue research. The aim of this study was to develop a new, more inclusive classification for TMJ HO. Currently available classifications were evaluated and a Delphi-type system used to build consensus from clinicians and researchers to develop a new system. Fourteen unique classifications for TMJ ankylosis/HO were identified. In light of the biological specifics related to heterotopic calcification of extracellular matrix versus heterotopic formation of actual bone, the group recommends a more unambiguous term - peri-articular bone formation - and proposes a new classification. This will help clinicians and researchers to study, describe, and manage various types of ectopic bone associated with the TMJ.

Effect of occlusal stabilisation splint with or without arthroscopic disc repositioning on condylar bone remodelling in adolescent patients.

The aim of this study was to investigate the treatment effects of a stabilisation splint (SS) with and without arthroscopic disc repositioning (ADR) on condylar bone remodelling in adolescent patients with anterior disc displacement without reduction (ADDwoR). Cone beam computed tomography and magnetic resonance imaging were used to analyse condylar bone remodelling, condyle position, and disc position. Twenty-two temporomandibular joints of 14 patients who underwent ADR (age range 12-20 years; mean follow-up 12.5 ± 7.8 months) and 21 temporomandibular joints of 14 patients who did not undergo ADR (age range 13-20 years; mean follow-up 11.1 ± 5.1 months) were included. The change in bone volume (P < 0.001), rate of bone volume change (P < 0.001), and change in condyle height (P = 0.031) were significantly greater in patients with ADR than in those without ADR. The changes in posterior joint space (P = 0.013), superior joint space (P = 0.020), and ratio of condyle sagittal position (P = 0.013) were significantly greater in patients with ADR than in those without ADR. All discs in patients who underwent ADR and one disc in those who did not undergo ADR were backward repositioned. In conclusion, in adolescent patients with ADDwoR, ADR with SS therapy achieved better condyle and disc position than SS therapy alone, and also induced bone generation.

Pharmacological Treatments of Temporomandibular Disorders: A Systematic Review Including a Network Meta-Analysis.

OBJECTIVE: Temporomandibular disorders (TMD) comprise a cluster of conditions with a wide range of etiological factors that causes pain and discomfort in the masticatory muscles (TMD-M) and temporomandibular joints (TMD-J). More than 50% of the patients with TMD report regular usage of drugs. However, there is still no consensus, nor is there any evidence-based support for clinicians when choosing between different drugs. Therefore, this systematic review, including a network meta-analysis (NMA), aimed to evaluate the scientific evidence and discuss the pharmacological treatment options available to treat painful TMD. METHOD: An electronic search was undertaken to identify randomized controlled trials (RCTs) investigating pharmacological treatments for TMD-M and/or TMD-J, published until 6 April 2023. Since only 11 articles could be used for an NMA regarding TMD-M, a narrative synthesis was also performed for all 40 included RCTs. The quality of evidence was rated according to Cochrane's tool for assessing risk of bias, while the certainty of evidence was rated according to Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: When it comes to TMD-M, evidence arises for wet needling therapies with BTX-A, granisetron, and PRP as well as muscle relaxants. For TMD-J, evidence points toward pharmacological treatment approaches including non-steroidal antiinflammatory drugs (NSAIDs) and glucocorticosteriods (for inflammatory conditions) as well as hyaluronic acid and dextrose. CONCLUSIONS: The evidence clearly indicates that the pharmacological treatment approaches differ between TMD-M and TMD-J. Therefore, it is of great importance to first try to uncover each patient's individual and multifactorial etiology and then employ a multifaceted treatment strategy, including pharmacological treatment approaches.

Temporomandibular joint surgery: the past, present, and future.

Temporomandibular joint surgery for various pathological conditions and diseases affecting the integrity, mobility, and function of the joint has a long history. However, the greatest explosion of knowledge regarding the diagnosis and management of temporomandibular joint pain, pathology, and rehabilitation has occurred in the last 50 years. This review focuses on the incremental expansion of knowledge over time that led to the development of concepts that support our current surgical decisions and techniques, with the aim of identifying gaps in knowledge that require well-designed studies to move the field forward. Using this approach will allow an enhancement of our understanding of temporomandibular joint form and function, and enable focus to be placed on the evaluation, diagnosis, and non-surgical and surgical management strategies that are the most efficacious for our patients.

Mechanical stress can regulate temporomandibular joint cavitation via signalling pathways.

The temporomandibular joint (TMJ), composed of temporal fossa, mandibular condyle and a fibrocartilage disc with upper and lower cavities, is the biggest synovial joint and biomechanical hinge of the craniomaxillofacial musculoskeletal system. The initial events that give rise to TMJ cavities across diverse species are not fully understood. Most studies focus on the pivotal role of molecules such as Indian hedgehog (Ihh) and hyaluronic acid (HA) in TMJ cavitation. Although biologists have observed that mechanical stress plays an irreplaceable role in the development of biological tissues and organs, few studies have been concerned with how mechanical stress regulates TMJ cavitation. Based on the evidence from human or other animal embryos today, it is implicated that mechanical stress plays an essential role in TMJ cavitation. In this review, we discuss the relationship between mechanical stress and TMJ cavitation from evo-devo perspectives and review the clinical features and potential pathogenesis of TMJ dysplasia.

Biomechanical effects of joint disc perforation on the temporomandibular joint: a 3D finite element study.

BACKGROUND: Disc perforation (DP) is a severe type of Temporomandibular Disorder (TMD). DP may induce changes in the internal stresses of the temporomandibular joint (TMJ). Herein, this study attempts to investigate the biomechanical effects of different positions and sizes of DP on the TMJ using a biomechanical approach, to explore the mechanical pathogenesis of TMD. METHODS: Eleven three-dimensional finite element (FE)models of the TMJ were constructed based on CBCT imaging files of a patient with DP on the left side. These models included the disc with anterior displacement and discs with different locations and sizes of perforations on the affected disc. FE methods were conducted on these models. RESULTS: Anterior displacement of the disc leads to a significant increase in the maxim von Mises stress (MVMS) in both TMJs, with the affected side exhibiting a more pronounced effect. DP occurring at the posterior band and the junction between the disc and the bilaminar region has a greater impact on the MVMS of both TMJs compared to perforations at other locations. As the size of the perforation increases, both sides of the TMJs exhibit an increase in the magnitude of MVMS. CONCLUSIONS: Unilateral disc anterior displacement results in an increased stress on both TMJs. Unilateral DP further affects the stress on both sides of the TMJs. TMD is a progressive condition, and timely intervention is necessary in the early stages to prevent the worsening of the condition.

Photobiostimulation conjugated with stem cells or their secretome for temporomandibular joint arthritis in a rat model.

BACKGROUND: Temporomandibular joint (TMJ) arthritis is a debilitating, challenging condition and different methods have been implicated for its treatment. This study aimed to test the therapeutic potentials of low-level laser therapy (LLLT) associated with adipose derived stem cells (ADSC) or their derived secretome on a murine model induced arthritis. METHODS: Forty eight rats were divided into four groups where group I was the sham control, the rest of animals were subjected to arthritis induction using complete Freund's adjuvant, then divided as follows: group II received phosphate buffered saline (PBS) intraarticular injection and irradiation of 0 j/cm2, group III received ADSCs derived secretome and irradiation of 38 j/cm2, and group IV received ADSCs and irradiation of 38 j/cm2 as well. One and three weeks after treatment, animals were euthanized, and paraffin blocks were processed for histological assessment by hematoxylin and eosin stain with histomorphometrical analysis. Histochemical evaluation of joint proteoglycan content was performed through toluidine blue stain, and immunohistochemical staining by the proinflammatory marker tumor necrosis factor-α (TNF-α) was performed followed by the relevant statistical tests. RESULTS: The arthritis group showed histological signs of joint injury including cartilage atrophy, articular disc fibrosis, irregular osteochondral interface, and condylar bone resorption together with high inflammatory reaction and defective proteoglycan content. In contrast, the treated groups III and IV showed much restoration of the joint structure with normal cartilage and disc thickness. The inflammation process was significantly suppressed especially after three weeks as confirmed by the significant reduction in TNF-α positive immunostaining compared to the arthritic group, and the cartilage proteoglycan content also showed significant increase relative to the arthritic group. However, no significant difference between the results of the two treated groups was detected. CONCLUSION: LLLT conjugated with ADSCs or ADSCs derived secretome can efficiently enhance the healing of arthritic TMJs. Stem cell secretome can be applied as a safe, potent therapy. However, further investigations are required to unravel its mechanism of action and pave its way as a safe, novel, cell free therapy.

Potential of ultra-high-resolution CT in detecting osseous changes of temporomandibular joint: experiences in temporomandibular disorders.

BACKGROUND: Osseous changes of the temporomandibular joint (TMJ) are related to the progression of temporomandibular disorders (TMD), and computed tomography (CT) plays a vital role in disease evaluation. OBJECTIVE: The aims of this study were to evaluate the image quality and diagnostic value of ultra-high-resolution CT (U-HRCT) in TMD compared to cone-beam CT (CBCT). METHODS: TMD patients who underwent both CBCT and U-HRCT between November 2021 and September 2022 were retrospectively included. Image quality scores were assigned for four osseous structures (the cortical and trabecular bones of the condyle, articular eminence, and glenoid fossa) by two independent observers from Score 1 (unacceptable) to Score 5 (excellent). Diagnostic classification of TMD was categorized as follows: Class A (no evident lesion), Class B (indeterminate condition) and Class C (definitive lesion). Image quality scores and diagnostic classifications were compared between CBCT and U-HRCT. The Cohen's Kappa test, Wilcoxon signed-rank test, Chi-square test and Fisher's exact test were conducted for statistical analysis. RESULTS: Thirty TMD patients (median age, 30 years; interquartile range, 26-43 years; 25 females) with 60 TMJs were enrolled. Image quality scores were higher for U-HRCT than for CBCT by both observers (all Ps < 0.001). Definitive diagnoses (Class A and C) were achieved in more cases with U-HRCT than with CBCT (93.3% vs. 65.0%, Fisher's exact value = 7.959, P = 0.012). Among the 21 cases which were ambiguously diagnosed (Class B) by CBCT, definitive diagnosis was achieved for 17 cases (81.0%) using U-HRCT. CONCLUSIONS: U-HRCT can identify osseous changes in TMD, providing improved image quality and a more definitive diagnosis, which makes it a feasible diagnostic imaging method for TMD.

Loss of miR-204 and miR-211 shifts osteochondral balance and causes temporomandibular joint osteoarthritis.

Temporomandibular joint (TMJ) osteoarthritis (OA) is a common type of TMJ disorders causing pain and dysfunction in the jaw and surrounding tissues. The causes for TMJ OA are unknown and the underlying mechanism remains to be identified. In this study, we generated genetically-modified mice deficient of two homologous microRNAs, miR-204 and miR-211, both of which were confirmed by in situ hybridization to be expressed in multiple TMJ tissues, including condylar cartilage, articular eminence, and TMJ disc. Importantly, the loss-of-function of miR-204 and miR-211 caused an age-dependent progressive OA-like phenotype, including cartilage degradation and abnormal subchondral bone remodeling. Mechanistically, the TMJ joint deficient of the two microRNAs demonstrated a significant accumulation of RUNX2, a protein directly targeted by miR-204/-211, and upregulations of ß-catenin, suggesting a disrupted balance between osteogenesis and chondrogenesis in the TMJ, which may underlie TMJ OA. Moreover, the TMJ with miR-204/-211 loss-of-function displayed an aberrant alteration in both collagen component and cartilage-degrading enzymes and exhibited exacerbated orofacial allodynia, corroborating the degenerative and painful nature of TMJ OA. Together, our results establish a key role of miR-204/-211 in maintaining the osteochondral homeostasis of the TMJ and counteracting OA pathogenesis through repressing the pro-osteogenic factors including RUNX2 and ß-catenin.

Temporomandibular joint disc repositioning and occlusal splint for adolescents with skeletal class II malocclusion: a single-center, randomized, open-label trial.

BACKGROUND: Temporomandibular joint (TMJ) disc repositioning through open suturing (OSu) is a new disc repositioning method. Its result for adolescents with condylar resorption and dentofacial deformities combined with and without postoperative occlusal splints (POS) has not been well studied. OBJECTIVE: This study was to evaluate and compare the effects of OSu with and without POS in the treatment of TMJ anterior disc displacement without reduction (ADDwoR) in adolescent skeletal Class II malocclusion. METHODS: A total of 60 adolescents with bilateral ADDwoR were enrolled in this study. They were randomly allocated into two groups: OSu with and without POS. Magnetic resonance imaging (MRI) and lateral cephalometric radiographs were used to measure changes in condylar height and the degree of skeletal Class II malocclusion from before operation and at 12 months postoperatively. Changes in these indicators were compared within and between the two groups. RESULTS: After OSu, both groups exhibited significant improvements in condylar height and occlusion at the end of 12 months follow-up (P < 0.05). The group of OSu with POS had significantly more new bone formation (2.83 ± 0.75 mm vs. 1.42 ± 0.81 mm, P < 0.001) and improvement in dentofacial deformity than the group of OSu only (P < 0.05). The new bone height was significantly correlated with POS (P < 0.001), the changes of SNB (P = 0.018), overjet (P = 0.012), and Wits appraisal (P < 0.001). CONCLUSION: These findings indicated that OSu can effectively stimulate condylar regeneration and improve skeletal Class II malocclusion in adolescents with bilateral ADDwoR. The results are better when combined with POS. TRIAL REGISTRATION: This trial was prospectively registered on the chictr.org.cn registry with ID: ChiCTR1900021821 on 11/03/2019.

Ganglion cyst of temporomandibular joint - A systematic review.

Ganglion cyst of the temporomandibular joint (TMJ) is an uncommon pathology with uncertain etiology. There is no consensus on their management. The current systematic review aimed to discuss the clinical and histopathological features of ganglion cysts of TMJ, to aid in appropriate treatment. A literature search was done and a total of 20 cases were retrieved from published databases such as PubMed, SCOPUS, and Google Scholar. The cyst presented with swelling in all the cases followed by pain (50 %) and trismus (35 %) as other common symptoms. Though CT and MRI proved helpful in determining the location of the cyst, a histopathological examination was essential in concluding its final diagnosis. It is a pseudocyst lined by dense fibro-connective tissue with myxoid tissue degeneration. Histologically, it is essential to distinguish them from the clinically and radiographically similar true cyst of TMJ, synovial cyst. The lining of ganglion cyst is devoid of epithelium and synovial cells. Surgical excision was found to be the treatment of choice with minimal recurrence (10 %) being reported.

Evaluation of clinical signs and magnetic resonance imaging findings in patients with temporomandibular disorders.

This study assessed the relationship between clinical symptoms and magnetic resonance imaging (MRI) findings in temporomandibular disorders (TMD). A total of 324 temporomandibular joints (TMJs) from 162 patients were included. The TMJs were divided into three groups based on disc positions on MRI: normal disc position, anterior disc displacement with reduction (ADDwR), and anterior disc displacement without reduction (ADDwoR). Clinical findings included TMJ pain, TMJ noise, and maximum mouth opening (MMO). The disc configuration, disc positions, condylar morphology, and joint effusion were evaluated in proton density-weighted and T2-weighted open and closed-mouth sagittal sections. Patients comprised 135 females and 27 males, with a mean age of 37.63 ± 13.86 years. The VAS score was significantly higher in ADDwoR than in ADDwR (p = 0.007). Condylar sclerosis (ß coefficient: 1.449, 95% confidence interval (CI): 0.505-2.393, p = 0.003) and condylar flattening (ß coefficient: 1.024, 95% CI: 0.209-1.840, p = 0.014) had higher VAS scores than the other MRI findings in multiple regression analyses. Limited mouth opening (MO) was independently associated with ADDwoR. ADDwoR had a higher risk of having limited MO than normal disc position (odds ratio: 5.268), while there were no associations between limited MO and other MRI findings. None of the MRI findings showed significant performance in predicting TMJ noise. The convex and folded disc configuration percentages, the frequencies of osteophyte formation, and grade 3 effusion were significantly higher in the ADDwoR group. More severe clinical symptoms and a higher degree of disc deformity, osteophyte formation, and high-grade effusion were shown to be associated with ADDwoR.

Osteoarthritis Disease Severity in the Temporomandibular Joint and the Knee Joint: A Comparative Cadaveric Study.

OBJECTIVE: The objective of this study was to determine the level of disease severity in a pilot cohort of temporomandibular joints (TMJs) and compare them to the pathology findings previously characterized in cadaveric knee joints. DESIGN: Thirty-one intact TMJs from 17 cadaveric donors were harvested and arthritic lesioning seen in the knee joint was investigated on the condyle and the fossa of the TMJ. Prevalence of gross alterations was equated and disease severity was determined for sex- and age-based donor pools using a validated, osteoarthritis (OA) disease severity scale (DSS). Knee joint DSS scores were also compared to the TMJ condyle and fossa DSS scores and a case study was carried out on a male donor that demonstrated severe OA in the both joints. RESULTS: The mandibular fossa demonstrated an increase in disease severity compared to the mandibular condyle in a mixed sex donor pool (P = 0.035). It was discovered that the younger females demonstrated statistically more pathological condyles compared to the older half of the female subgroup (P = 0.02). TMJ fossa and knee joints demonstrated comparable OA severity and similar signs of cartilage disease in a single donor highlighting the systemic nature of OA. CONCLUSIONS: This study demonstrates that gross signs of OA in the TMJs of cadavers are comparable to pathology found in the knee. The mandibular fossa appears to be the site of more profound disease, implying translational movements may be more likely to induce biomechanically abnormal movement, loading, and OA.

Temporomandibular joint involvement in patients with Juvenile Idiopathic Arthritis: comparison of ultrasonography and magnetic resonance imaging in assessing the periarticular space width.

OBJECTIVES: This study aimed to compare the performance of Ultrasonography (US) and Magnetic Resonance Imaging (MRI) in assessing the Lateral Periarticular Space (LPAS) of Temporomandibular Joints (TMJs) in patients with Juvenile Idiopathic Arthritis (JIA). METHODS: The LPAS width was evaluated in two different patient groups. In the JIA group, including 29 children (13 ± 2.8 years) with JIA, the LPAS width was measured with both MRI and US. In the healthy group, including 28 healthy children (12.6 ± 2.5 years), the LPAS width was measured only with US. Comparisons of LPAS width based on patient groups and TMJ contrast enhancement in MRI were evaluated by applying the Mann-Whitney U test. Correlation and agreement between MRI and US measurements in JIA group were tested using Spearman rank correlation and Bland-Altman method. RESULTS: The LPAS width was significantly greater in the JIA group than in the healthy group. In the JIA group, the LPAS width was significantly greater in TMJs with moderate/severe enhancement than those with mild enhancement. A positive significant correlation between MRI and US measurements of LPAS width was found in the JIA group. In the same group, Bland-Altman method showed a good level of agreement between MRI and US measurements. CONCLUSION: Although, US cannot replace MRI in the evaluation of TMJ in patients with JIA, US could be used as a supplementary imaging method to MRI in assessing the TMJ disease.

Synovial chondromatosis: a case series and review of the literature.

This case series reviews 2 patients worked up and treated for unilateral synovial chondromatosis of the temporomandibular joint (TMJ). The first was a 58-year-old female evaluated and treated for synovial chondromatosis of the left TMJ using an arthrotomy of the joint to remove the cartilaginous and osteocartilaginous nodules. The second is a 63-year-old male who was evaluated and treated for synovial chondromatosis of the right TMJ with the removal of extracapsular masses and an arthrotomy with intra-joint removal of nodules. Six-year radiographic follow-up demonstrated no recurrence of the pathology in his case. The cases are reviewed in this article, along with a current review of the literature.