Temporomandibular joint arthritis in juvenile idiopathic arthritis: the forgotten joint

Comparison between ultrasound and magnetic resonance imaging of the temporomandibular joint in juvenile idiopathic arthritis: A systematic review

OBJECTIVES

The objectives of this systematic review were to evaluate the correlation between Ultrasound (US) and Magnetic Resonance Imaging (MRI) in patients with JIA and to investigate the association with Temporomandibular Disorders (TMD).

MATERIALS AND METHODS

The protocol was registered in PROSPERO (CRD42022312734). Databases Medline, Embase, Cochrane Central Register of Controlled Trials, Scopus, Web of Science, Latin American and Caribbean Health Sciences Literature were searched. Eligibility criteria were patients with JIA subjected to diagnostic evaluation using US and MRI. No language restrictions were applied. After duplicate study selection, data extraction and risk of bias assessment according to Cochrane were conducted. Data extraction of patients was conducted by two independent authors.

RESULTS

Five observational studies were included with 217 participants (153 females and 64 males; mean age 11.3 years). The quality of the studies was overall satisfactory. The correlation between US and MRI in children with JIA was 'moderate' in acute arthritis while the chronic arthritis correlated positively in two studies.

CONCLUSIONS

Even if MRI remains the more accurate imaging modality for the detection of TMJ of patients with JIA, US may be useful to early detect pathological conditions and to address the patient with JIA and putative TMJ involvement to a more accurate diagnosis with MRI and consequent appropriate treatment management.

CLINICAL RELEVANCE

MRI should be deemed necessary only secondary to less-invasive assessments with US just to confirm the diagnosis or to increase sensitivity, accuracy of positive predictive values detected.

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.

Recent Advances in Temporomandibular Joint Surgery

Temporomandibular disorders (TMDs) affect a high percentage of children and adults worldwide. Surgery may be indicated in severe or recalcitrant cases. Several recent advancements in TMD and temporomandibular joint (TMJ) surgery have elevated understanding and the ability to treat affected patients. We discuss recent advances in TMD epidemiology, juvenile idiopathic arthritis (JIA) of the TMJ, and surgical techniques and technologies. Technical advancements have been identified in TMJ arthroscopy, the treatment of TMJ subluxation and dislocation, and extended prosthetic total TMJ reconstruction (eTMJR). Overall, this review provides valuable insights into significant recent advancements in TMJ disorders and their surgical management.

Challenges in treating juvenile idiopathic arthritis

PURPOSE OF REVIEW

Juvenile idiopathic arthritis (JIA) diagnosis and classification is currently still based on clinical presentation and general laboratory tests. Some joints such as the temporomandibular joint (TMJ) and sacroiliac (SI) are hard to assess and define as actively inflamed based on clinical examination. This review addresses these difficult to assess joints and provides the latest evidence for diagnosis and treatment.

RECENT FINDINGS

Recommendations on clinical examination and radiological examination are available. Recent 2021 ACR recommendations were made for TMJ arthritis and in 2019 for sacroiliitis.

SUMMARY

New evidence to guide clinical suspicion and need for further investigations are available for these hard to assess joints. These guidelines will help healthcare providers in diagnosis and treatment assessment.

Diagnosis of juvenile idiopathic arthritis with asymptomatic involvement of the temporomandibular joint: A case report

Juvenile idiopathic arthritis (JIA) is a broad term that describes a group of heterogeneous rheumatologic diseases, mainly characterized by inflammation in the joints of children and young people up to 16 years of age. Its etiology is still not well understood and the diagnosis, essentially clinical, begins with the exclusion of other joint diseases. When the disease affects the temporomandibular joint, diagnosis is a challenge, as many patients are asymptomatic. The objective of this paper is to present a case of JIA with severe involvement of the temporomandibular joint and to discuss the clinical, radiographic, laboratory findings and the importance of early diagnosis. The lack of diagnosis of active arthritis in the temporomandibular joint in patients with JIA can cause irreversible effects such as micrognathia, malocclusion and reduced maximum mouth opening. Early diagnosis of temporomandibular joint involvement in JIA is important and needs to be investigated early in the clinical manifestation of systemic disease. Laboratory tests and clinical history are important to define treatment and prognosis, but not to predict temporomandibular joint arthritis. Imaging exams are important diagnostic tools to identify morphological changes in soft and hard tissues of the temporomandibular joint.

Craniofacial structures, occlusal features, and TMD symptoms in juvenile idiopathic arthritis patients: a retrospective study

BACKGROUND

Juvenile idiopathic arthritis (JIA) is a chronic inflammatory disease in which temporomandibular joint (TMJ) arthritis commonly occurs. It may be asymptomatic and could cause problems in the growing joints. Our aim was to evaluate the craniofacial structures, occlusal features and temporomandibular dysfunction (TMD) symptoms of patients with JIA.

METHODS

The study consisted of 195 JIA patients treated at the Department of Oral and Maxillofacial Diseases, Helsinki University Hospital (HUH), Finland between 2015 and 2019. We retrospectively screened their medical and dental records and classified them according to age at JIA diagnosis (<7 and ≥7 years).

RESULTS

Most of the patients had Angle Class I occlusion in both sides. Among all the patients, the mean overjet, and overbite were 3.3 mm and 2.4 mm, respectively. There were more open bite patients in the ≥7 years old group than in the <7 years old group (P = 0.010). Of all patients, 47% reported at least one TMD symptom. The TMD symptoms were more common in participants ≥7 years old than those <7 years old (P = 0.005).

CONCLUSION

Occlusal features and the incidence of malocclusions seem to have similar tendency among the JIA patients with systematic visits in rheumatologist and orthodontist as in the healthy population, except for open bite that is more common with JIA patients. While treating JIA patients, a well-functioning collaboration between paediatric rheumatologists and orthodontists is essential, as well as a clear screening protocol to detect potentially asymptomatic TMJ arthritis. Particular attention should be paid to children with JIA under school age.

Temporomandibular joint in juvenile idiopathic arthritis: magnetic resonance imaging measurements and their correlation with imaging findings

OBJECTIVE

The aim of this study was to investigate the TMJ components in patients with juvenile idiopathic arthritis (JIA) and to compare them with a control group based on magnetic resonance imaging (MRI) measurements.

METHODS

This study comprised an assessment of MRI measurements of 96 temporomandibular joints (TMJ) following classification criteria set by the International League of Associations for Rheumatology (ILAR). Three measurements were considered for study: condyle excursion angle (CEA), height of articular eminence (HAE) and inclination of articular eminence (IAE). All TMJs were assessed by linear measurements made by using the OnDemand 3D software. The comparison between the groups was performed by using Mann-Whitney's test.

RESULTS

Lower measurement values were found for IAE, HAE and CEA in JIA patients (P-values < 0.001, 0.005 and < 0.001, respectively).

CONCLUSION

The study showed the differences in MRI measurements between JIA patients and controls, with the former with the lowest indices.

Electromyographic Activity of Masticatory Muscles in Subjects with Juvenile Idiopathic Arthritis: A Case—Control Study

The aim of this study was to evaluate the effect of juvenile idiopathic arthritis (JIA) on the activity of masticatory muscles using surface electromyography (sEMG). Forty-one JIA subjects (ten males, thirty-one females; average age 13 years ± 3) and thirty-two healthy control subjects (twenty-seven females, five males; average age 14 years ± 2) were recruited. sEMG of anterior temporalis (TA), masseter (MM), and sternocleidomastoid (SCM) muscles was performed by using the occlusal contact analyzer software called Teethan (BTS S.p.A., Garbagnate Milanese, Milan, Italy). Comparisons between groups were assessed with unpaired t-tests for non-normally distributed data and with Mann–Whitney U tests for normally distributed parameters. The JIA group showed a significant increased percentage overlapping coefficient of TA (POC TA) (p = 0.01) and impact index (IMP) (p = 0.003). No significant differences were observed for the POC MM, POC SCM, percentage overlapping coefficient between posterior and anterior teeth contact (BAR), the torsion index (TORS), and the asymmetry index (ASIM). Masticatory muscles seemed to be slightly affected by JIA. sEMG could be an effective aid in the early clinical detection of TMJ involvement in JIA. Further research is needed to confirm its validity.

A 3D CBCT Analysis of Airway and Cephalometric Values in Patients Diagnosed with Juvenile Idiopathic Arthritis Compared to a Control Group

Introduction: The temporomandibular joint (TMJ) is affected in 30–45% of juvenile idiopathic arthritis (JIA) patients, with all JIA subtypes at risk for TMJ involvement. JIA patients with TMJ involvement may present with altered craniofacial morphology, including micrognathia, mandibular retrognathia, a hyperdivergent mandibular plane angle, and skeletal anterior open bite. These features are also commonly present and associated with non-JIA pediatric patients with obstructive sleep apnea (OSA). Materials and Methods: The study was comprised of a group of 32 JIA patients and a group of 32 healthy control subjects. CBCT images were taken for all patients and were imported into Dolphin Imaging software. The Dolphin Imaging was used to measure the upper airway volumes and the most constricted cross-sectional areas of each patient. Cephalometric images were rendered from the CBCT data for each patient, and the following cephalometric values were identified: SNA angle, SNB angle, ANB angle, anterior facial height (AFH), posterior facial height (PFH), mandibular plane angle (SN-MP), FMA (FH-MP), overjet (OJ), and overbite (OB). Airway volumes, the most constricted cross-sectional area values, and cephalometric values were compared between the JIA and control groups. Results: For airway values, statistically significant differences were seen in the nasopharynx airway volume (p = 0.004), total upper airway volume (p = 0.013), and the most constricted cross-sectional area (p = 0.026). The oropharynx airway volume was not statistically significant (p = 0.051). For cephalometric values, only the posterior facial height showed a statistically significant difference (p = 0.024). Conclusions: There was a significant difference in airway dimensions in the JIA patients as compared to the control patients. In addition, the posterior facial dimensions seem to be affected in JIA patients. The ODDs ratio analysis further corroborated the findings that were significant.

Controversial Aspects of Diagnostics and Therapy of Arthritis of the Temporomandibular Joint in Rheumatoid and Juvenile Idiopathic Arthritis-An Analysis of Evidence- and Consensus-Based Recommendations Based on an Interdisciplinary Guideline Project

Introduction: Due to potentially severe sequelae (impaired growth, condylar resorption, and ankylosis) early diagnosis of chronic rheumatic arthritis of the temporomandibular joint (TMJ) and timely onset of therapy are essential. Aim: Owing to very limited evidence the aim of the study was to identify and discuss controversial topics in the guideline development to promote further focused research. Methods: Through a systematic literature search, 394 out of 3771 publications were included in a German interdisciplinary guideline draft. Two workgroups (1: oral and maxillofacial surgery, 2: interdisciplinary) voted on 77 recommendations/statements, in 2 independent anonymized and blinded consensus phases (Delphi process). Results: The voting results were relatively homogenous, except for a greater proportion of abstentions amongst the interdisciplinary group (p < 0.001). Eighty-four percent of recommendations/statements were approved in the first round, 89% with strong consensus. Fourteen recommendations/statements (18.2%) required a prolonged consensus phase and further discussion. Discussion: Contrast-enhanced MRI was confirmed as the method of choice for the diagnosis of TMJ arthritis. Intraarticular corticosteroid injection is to be limited to therapy-refractory cases and single injection only. In adults, alloplastic joint replacement is preferable to autologous replacement. In children/adolescents, autologous reconstruction may be performed lacking viable alternatives. Alloplastic options are currently still considered experimental.

Clinical Practice Guideline: The Diagnosis and Treatment of Rheumatoid Arthritis and Juvenile Idiopathic Arthritis of the Temporomandibular Joint

BACKGROUND

Involvement of the temporomandibular joint can be shown in 40-90% of patients with rheumatoid arthritis and juvenile idiopathic arthritis (JIA), although it is often asymptomatic. Restricted jaw mobility and jaw pain can be found in approximately 20% of patients with JIA (prevalence: 70 per 100 000 persons). Early diagnosis and treatment of the underlying disease are essential for a good outcome, but uniform, consensus-based management is still lacking.

METHODS

The clinical practice guideline is based on the findings of a systematic literature review in multiple databases and a Delphi procedure to obtain consensus on the recommendations.

RESULTS

Most of the identified studies were retrospective. Patients with JIA should undergo clinical screening with a structured examination protocol once per year in childhood and adolescence, and thereafter as well if the temporomandibular joint is involved. The diagnosis of chronic rheumatoid arthritis of the temporomandibular joint is established with contrastenhanced magnetic resonance imaging. Conservative treatment (antirheumatic basal therapy, local measures) is unsuccessful in less than 10% of patients. In such cases, arthroscopy and arthrocentesis can be used for temporary symptom relief and functional improvement. Intraarticular corticosteroid injections should be given only once, and only in otherwise intractable cases. In severe cases where all other options have been exhausted (<1%), open surgical treatment can be considered, including alloplastic joint replacement.

CONCLUSION

Oligosymptomatic and asymptomatic cases are common even with radiologic evidence of marked joint damage. The possibility of rheumatic involvement of the temporomandibular joint must be kept in mind so that serious complications can be avoided. Regular clinical evaluation of the temporomandibular joint is recommended, particularly for patients with juvenile idiopathic arthritis.

Three-dimensional volumetric evaluation of the different mandibular segments using CBCT in patients affected by juvenile idiopathic arthritis: a cross-sectional study

BACKGROUND

There is currently no information on how different mandibular segments are affected by juvenile idiopathic arthritis. The aim of this paper is to assess volumetric differences of different mandibular segments in subjects with unilateral and bilateral JIA and to compare them with non-JIA control volumes.

MATERIALS AND METHODS

Forty subjects with unilateral TMJ involvement and 48 with bilateral TMJ involvement were selected for the case group and 45 subjects with no known rheumatic comorbidities for the control group. The mandible of each subject was divided according to a validated method into different paired volumes (hemimandible, condyle, ramus and hemibody).

RESULTS

The ANOVA test revealed a statistically significant difference in all the groups for condylar and ramus volumes, and the pairwise comparison evidenced a statistically significant higher condylar and ramus volume in the control group (1444.47 mm³; 5715.44 mm³) than in the affected side in the unilateral JIA group (929.46 mm³; 4776.31 mm³) and the bilateral JIA group (1068.54 mm³; 5715.44 mm³). Moreover, there was also a higher condylar volume in the unaffected side in the unilateral JIA group (1419.39 mm³; 5566.24 mm³) than in the bilateral JIA group and the affected side in the unilateral JIA group.

CONCLUSIONS

The affected side of unilateral JIA patients showed statistically significant lower volumes in the hemimandible, in the condyle and in the ramus. The largest total mandibular volume was observed in the control group, followed by the unilateral JIA group and, lastly, by the bilateral JIA group.

Does Combined Temporomandibular Joint Reconstruction With Patient Fitted Total Joint Prosthesis and Orthognathic Surgery Reduce Symptoms in Juvenile Idiopathic Arthritis Patients?

PURPOSE

Patients with juvenile idiopathic arthritis (JIA) and TMJ involvement may have major dentofacial deformities, pain, and jaw dysfunction. The aim of this study was to evaluate surgical outcomes for JIA patients relative to TMJ pain, headache, jaw function, diet, disability, and quality-of-life (QOL) after TMJ reconstruction with patient-fitted total joint prostheses (TJP) and concomitant orthognathic surgery.

METHODS

A retrospective cohort study was conducted on a JIA patient group (JIAG) with significant dentofacial deformity, reconstructed with TJP and concomitant orthognathic surgery, and was compared to a control group (CG) of non-JIA patients that received the same surgical protocol with similar surgical movements. Primary predictors were the 2 groups: JIAG and CG. Data were evaluated and compared presurgery and at longest follow-up using Likert analog scales for the primary variables: TMJ pain, headache, jaw function, diet, and disability. Maximum interincisal opening (MIO) was measured in mm. QOL was rated in JIAG as improved, same, or worse. Comparative data were tested for significance (α = 0.05) using Wilcoxon signed rank and paired T-tests.

RESULTS

Forty JIAG patients (8 males, 32 females) met the inclusion criteria, median age 17.5 years, median follow-up 26.5 months, and 26 CG patients (1 male, 25 females), median age 35.5 years, follow-up 24 months. Significant improvements (P ≤ .05) occurred postsurgery for TMJ pain, headache, jaw function, diet, and disability for both groups. Mean increase MIO for JIAG was 36.4 to 43.3 mm, for CG was 35.2 to 37.8 mm. Thirty-eight JIA patients (95%) improved in QOL, 2 had no change, and none were worse.

CONCLUSIONS

This study suggests that patient-fitted TJP for TMJ reconstruction in conjunction with orthognathic surgery for the JIA patient provides long-term improvement relative to TMJ pain, headache, jaw function, diet, disability, MIO, and QOL.

Does Combined Temporomandibular Joint Reconstruction With Patient-Fitted Total Joint Prosthesis and Orthognathic Surgery Provide Stable Skeletal and Occlusal Outcomes in Juvenile Idiopathic Arthritis Patients?

PURPOSE

To determine skeletal and occlusal surgical changes and long-term stability outcomes for patients diagnosed with juvenile idiopathic arthritis (JIA) after TMJ reconstruction with TMJ Concepts patient-fitted total joint prostheses (TJP) and concomitant maxillary orthognathic surgery.

MATERIAL/METHODS

A retrospective cohort study was conducted of all patients diagnosed with JIA, receiving TJP, and concomitant maxillary orthognathic surgery between 1991 and 2019, at Baylor University Medical Center treated by 1 surgeon. Patient evaluations presurgery (T1), immediate postsurgery (T2), and at longest follow-up (LFU) (T3) were analyzed using 20 cephalometric landmarks to compute 29 linear and angular measurements to determine surgical changes, long-term skeletal and occlusal stability, as well as oropharyngeal airway changes. Comparative data were tested for significance (α = 0.05) using paired and unpaired t tests.

RESULTS

Forty-two patients met the JIA inclusion criteria, with a median age of 17.5 years and median postsurgical follow-up of 26 months. There were significant surgical changes (T1-T2) (P ≤ .05) for all parameters associated with mandibular linear and angular surgical changes, except for the horizontal position of posterior nasal spine and the vertical/horizontal position of gonion, indicating highly stable surgical outcomes. There were significant improvements in the oropharyngeal airway dimensions.

CONCLUSIONS

This study suggests that TMJ Concepts patient-fitted TJP for TMJ reconstruction in conjunction with maxillary orthognathic surgery for counterclockwise rotation of the maxillo-mandibular complex for the JIA patients provides long-term skeletal and occlusal stability as well as dimensional improvement in the oropharyngeal airway.

Comparison of the condyle-fossa relationship and resorption between patients with and without Juvenile Idiopathic Arthritis (JIA)

INTRODUCTION

The most common disease in pediatric rheumatology is juvenile idiopathic arthritis (JIA). JIA is considered to be an autoimmune disease with an onset before the age of 16. The temporal mandibular joint (TMJ) has been reported to be involved in up to 87% of patients with JIA. Even though substantial research has been conducted on JIA, limited research has studied to understand its effect on the condyle-fossa relationship and to evaluate resorption amount on condyle by using a scoring system.

AIM

The purpose of this study was 1) to compare condyle - fossa relationships in the temporomandibular joint (TMJ), 2) was to score condylar resorption by using a TMJ indexing system in patients with JIA and without JIA.

METHODS

The present retrospective cross-sectional study included cone-beam computed tomography (CBCT) images obtained from the sagittal, coronal, and axial slices. In the multidisciplinary Pediatric Rheumatology Outpatient Clinic at The University of Alabama at Birmingham (UAB) children with JIA are also examined by a group of orthodontists working in the same institute from October 2018 to July 2019. The predictor variable consists of patients with JIA and without JIA. The primary outcome variables are the depth of the mandibular fossa, joint spaces, axial angles, medio-lateral width, and condyle resorption. Other study variables were age and sex. In this study, the measurements obtained from 2 different groups (with JIA and without JIA) are compared using a t-test, where Tukey is utilized to adjust for multiple comparisons. The left and right joints are analyzed separately as the paired t test conducted showed a significant difference between the 2 joints (P < .05).

RESULTS

The study was comprised of 34 patients diagnosed with JIA and 34 healthy subjects. The depth of the mandibular fossa, the anterior joint spaces, the axial angles, and the resorption index showed statistically significant differences between the JIA and healthy groups in both left and right sides (P < .05). However, there was no statistically significant difference in the posterior joint spaces and mediolateral width between JIA and healthy groups in both sides (P > .05).

CONCLUSIONS

The results of our study presented the destructive potential of juvenile idiopathic arthritis by using CBCT. CBCT scanning is a helpful tool in the evaluation of the radiographic result of TMJ.

Analysis of Earlier Temporomandibular Joint Disorders in JIA Patients: A Clinical Report

The aim of this study was to analyse the structural characteristics of the temporo-mandibular joint (TMJ) and the dysfunctional consequences induced by disease in subjects with juvenile idiopathic arthritis (JIA). The study was conducted in 25 patients with JIA (median age (IQR), 13.9 (10.9-15.3)) and 26 healthy controls (median age (IQR), 14.3 (11.6-17.2)) years. All enrolled patients were subjected to anamnestic evaluation, laboratory parameters, JIA subclass, and type of therapy for the disease. A clinical-gnathological evaluation, anamnestic and dysfunctional index (Ai and Di), and magnetic resonance imaging of TMJs were performed in all patients. The test group showed a significant reduction (p < 0.001) regarding the clinical findings such as maximal mouth opening, left and rightward laterotrusion and protrusion, and a significant difference in the reported symptoms (TMJ sounds, reduced mouth opening and pain), and Ai and Di (p < 0.001) compared to healthy patients. Correlation analysis showed a significant correlation between the median duration of disease and the maximum mouth opening and between visual analogue scale (VAS) score and maximum mouth opening, leftward laterotrusion, rightward laterotrusion, and protrusion. The results obtained in this study suggest that patients with JIA presented a cohort of symptoms in TMJs in comparison with healthy controls. Moreover, a careful TMJs evaluation and an early diagnosis of TMJs dysfunction and regular follow-ups are recommended in order to prevent and reduce functional and chewing problems in patients with JIA.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis: A single tertiary-center experience

OBJECTIVES

To describe the clinical and laboratory characteristic, state the treatment and outcome of patients with juvenile idiopathic arthritis (JIA), and describe temporomandibular joint (TMJ) involvement as observed in a large tertiary center.

METHODS

A retrospective cross-sectional study of children diagnosed with JIA was assessed at King Abdullah Specialist Children's Hospital, Riyadh, Saudi Arabia (2015-2019), which included a descriptive analysis of children who had TMJ involvement among our study group. Subjects diagnosed with the TMJ arthritis were based either on clinical musculoskeletal examination or using contrast-enhanced MRI.

RESULTS

We reviewed 123 cases with different JIA subtypes (57% females). The most frequent subtype is the oligoarticular (36%). TMJ involvement was found in 16% (n=20/123) of the patients, of whom 45% had Polyarticular JIA. The rheumatoid factor was positive in 25%; antinuclear antibody (ANA) in 45% and none showed positivity to HLAB27. Treatment resulted in complete resolution in 95% of cases, while Micrognathia and obstructive sleep apnea were the complications reported in 5% of cases.

CONCLUSION

TMJ involvement in JIA is not uncommon. Females with polyarticular disease were more frequently affected with TMJ arthritis. Positive ANA could be a risk factor for TMJ involvement, while positive HLAB27 might have some protective effects. Early treatment for TMJ arthritis is essential to avoid possible complications.

Mandibular range of motion in children with juvenile idiopathic arthritis with and without clinically established temporomandibular joint involvement and in healthy children; a cross-sectional study

BACKGROUND

Recognition of temporomandibular joint (TMJ) involvement in children with juvenile idiopathic arthritis (JIA) has gained increasing attention in the past decade. The clinical assessment of mandibular range of motion characteristics is part of the recommended variables to detect TMJ involvement in children with JIA. The aim of this study was to explore explanatory variables for mandibular range of motion outcomes in children with JIA, with and without clinically established TMJ involvement, and in healthy children.

METHODS

This cross-sectional study included children with JIA and healthy children of age 6-18 years. Mandibular range of motion variables included active and passive maximum interincisal opening (AMIO and PMIO), protrusion, laterotrusion, dental midline shift in AMIO and in protrusion. Additionally, the TMJ screening protocol and palpation pain were assessed. Adjusted linear regression analyses of AMIO, PMIO, protrusion, and laterotrusion were performed to evaluate the explanatory factors. Two adjusted models were constructed: model 1 to compare children with JIA and healthy children, and model 2 to compare children with JIA with and without TMJ involvement.

RESULTS

A total of 298 children with JIA and 169 healthy children were included. Length was an explanatory variable for the mandibular range of motion excursions. Each centimeter increase in length increased AMIO (0.14 mm), PMIO (0.14 mm), and protrusion (0.02 mm). Male gender increased AMIO by 1.35 mm. Having JIA negatively influenced AMIO (3.57 mm), PMIO (3.71 mm), and protrusion (1.03 mm) compared with healthy children, while the discrepancy between left and right laterotrusion raised 0.68 mm. Children with JIA and TMJ involvement had a 8.27 mm lower AMIO, 7.68 mm lower PMIO and 0.96 mm higher discrepancy in left and right laterotrusion compared to healthy children.

CONCLUSION

All mandibular range of motion items were restricted in children with JIA compared with healthy children. In children with JIA and TMJ involvement, AMIO, PMIO and the discrepancy between left and right laterotrusion were impaired more severely. The limitation in protrusion and laterotrusion was hardly clinically relevant. Overall, AMIO is the mandibular range of motion variable with the highest restriction (in millimeters) in children with JIA and clinically established TMJ involvement compared to healthy children.

Maximum bite force in children with juvenile idiopathic arthritis with and without clinical established temporomandibular joint involvement and in healthy children: a cross-sectional study

Background

In children with juvenile idiopathic arthritis (JIA), the temporomandibular joint (TMJ) can be involved, resulting in dysfunction of the masticatory system. Bite force is one of the variables that reflects the function of the masticatory system. The aim of this study was to compare maximum bite force in children with JIA, with and without TMJ involvement and with healthy children.

Methods

Children with JIA and healthy children between the ages 6 and 18 were included in this cross‐sectional study. The clinical examination consisted of measuring the anterior maximum voluntary bite force (AMVBF), assessment of the TMJ screening protocol items and TMJ, masseter and temporal muscle palpation pain. Unadjusted linear regression analyses were performed to evaluate the explanatory factors for AMVBF. Two adjusted models were constructed with corrections for age and gender differences: model 1 to compare children with JIA and healthy children and model 2 to compare children with JIA with and without TMJ involvement.

Results

In this cross‐sectional study, 298 children with JIA and 169 healthy children participated. AMVBF was 24 Newton (N) lower in children with JIA, when compared with healthy children (95%CI: −35.5–−12.4, p = .000). When children with JIA also had clinically established TMJ involvement, AMVBF was reduced 42 N (component JIA:−16.78, 95% CI −28.96–−4.59, p = .007 and component TMJ involvement:−25.36, 95% CI −40.08–−10.63, p = .001). Age and male gender increased AMVBF.

Conclusion

Children with JIA had a reduction in the AMVBF compared with healthy children. In children with JIA and clinically established TMJ involvement, AMVBF was more reduced.

Juvenile idiopathic arthritis of the temporomandibular joint - no longer the forgotten joint

Juvenile idiopathic arthritis (JIA) of the temporomandibular joint (TMJ) is common in children, with an increasing awareness of the condition in all healthcare professionals. TMJ involvement presents a challenge in both diagnosis and treatment, as late presentation can still occur as the disease often develops asymptomatically. This can result in facial deformity and/or functional difficulties including obstructive sleep apnoea. Early diagnosis is therefore essential, requiring a high index of clinical suspicion coupled with the judicious use of gadolinium contrast magnetic resonance imaging (MRI). Long-term management is best provided by a multidisciplinary team as patients often need a combination of pharmacological management, surgical interventions, orthodontics, and psychological support. End stage deformity can be treated by different surgical options, each with their own risks and benefits, however recently there is increasing recognition for the role of total alloplastic TMJ replacement. This review focuses on the diagnosis and management of TMJ arthritis and aims to highlight the important role of maxillofacial surgeons in JIA treatment.

Management of juvenile idiopathic arthritis: Preliminary qualitative findings from the National Dental Practice-Based Research Network

INTRODUCTION

Juvenile idiopathic arthritis (JIA) is the most common chronic arthritis in childhood and represents a series of chronic inflammatory arthritides that develop before 16 years of age.

METHODS

In 2020, investigators with an interest in the management of JIA engaged the National Dental Practice-Based Research Network by conducting a preliminary qualitative questionnaire ("Quick Poll") that comprised 6 questions about JIA management.

RESULTS

A total of 604 persons responded. Results suggested that there was an interest in the management of JIA, but many clinicians did not feel that they had the necessary knowledge or experience to treat these patients.

CONCLUSIONS

The study clearly highlights a distinct gap in awareness and understanding of JIA among clinicians polled. Future work in this area should focus on education and awareness across multiple specialties, clinical guidelines for the management of JIA, and a data repository of long-term outcomes.

Collagen-Induced Temporomandibular Joint Arthritis Juvenile Rat Animal Model

Juvenile idiopathic arthritis can affect the temporomandibular joint (TMJ) can cause growth disturbances of the lower jaw (mandible). The collagen-induced arthritis (CIA) juvenile rat model may be an appropriate model for studying how juvenile arthritis affects this joint during growth. However, studies using this animal model to investigate TMJ arthritis are limited. To validate an animal model for studying TMJ arthritis in growing rats, our study aimed to investigate the changes in mandibular growth and expression of proteins and cytokines in the mandibular condyle of CIA juvenile rat TMJs. A total of 27 male Wistar rats (3 weeks old) were scanned with microcomputed tomography (MicroCT) and divided into three groups (n = 9); CIA was induced in each TMJ in the CIA group, the Saline group received saline injections (sham injections) into their TMJs, and the Healthy group remained untreated (no TMJ injections) as negative controls. After 4 weeks, our results show that mandibular growth was significantly reduced in the CIA group compared with the Saline group (p < 0.01). There was no difference in mandibular growth between the two control groups (Saline and Healthy). Inflamed synovial tissue, cartilage invaginations, and lipid accumulation were observed in the CIA TMJs. Toluidine blue staining revealed decreased proteoglycan production in the CIA cartilage. In addition, immunohistochemistry revealed that type II collagen expression decreased, interleukin-1β expression increased, and matrix metalloproteinase-13 expression increased in the CIA TMJs in comparison with the two control groups (Saline and Healthy). Immunostaining of tumor necrosis factor-α (TNF-α) was quantified and we showed that TNF-α expression was significantly greater in the CIA cartilage compared with both control groups (p < 0.05), and there was no difference in TNF-α expression between the Saline and Healthy groups. This CIA juvenile rat model of TMJ juvenile arthritis shows that CIA reduced mandibular growth and induced degenerative changes in TMJ condylar cartilage. This new information will help to understand the pathogenesis involved in CIA in juvenile rat TMJs for this animal model to be used in research investigating new therapeutics to treat TMJ juvenile arthritis. Impact statement In this study, the effects of collagen-induced arthritis (CIA) on the temporomandibular joint (TMJ) using a juvenile rat model were investigated. Our results showed that local injection of CIA in the TMJ significantly reduced mandibular growth and caused degenerative changes in condylar cartilage. This information helps to validate this animal model for studying the effect of arthritis in TMJs in growing rats. This model has the potential to be used in future studies to evaluate possible therapies for TMJ arthritis.

Temporomandibular joint involvement in patients with juvenile idiopathic arthritis: a retrospective chart review

OBJECTIVE

To study the proportion of patients with temporomandibular joint (TMJ) involvement among patients with juvenile idiopathic arthritis (JIA), as well as associated clinical characteristics and signs/symptoms.

METHOD

We performed a retrospective chart review on consecutive patients followed in the Hamburg Centre for Paediatric and Adolescent Rheumatology Eilbek between January 2010 and July 2012. TMJ involvement was diagnosed based on clinical examination; a subgroup of patients was also assessed by magnetic resonance imaging (MRI).

RESULTS

The study included 2413 patients with JIA (52.1% girls, mean age at JIA onset 9.5 years). The most frequent JIA category was oligoarthritis (46.6%), followed by enthesitis-related arthritis (ERA; 38.1%). TMJ involvement was diagnosed in 843/2413 patients (34.9%) (677 MRI-confirmed, four not MRI-confirmed, no MRI examination in 162). Female gender (p = 0.017), higher number of additional joints with active arthritis (p < 0.001), anti-nuclear antibody (ANA) positivity (p = 0.005), higher age (p = 0.020), and oligoarthritis (persistent and extended; p = 0.043) were significantly associated with TMJ involvement. Human leucocyte antigen-B27-positive patients were less likely to have TMJ involvement (p = 0.023). Pain on palpation and pain while chewing were statistically significantly associated with TMJ involvement (p = 0.008 and p = 0.020, respectively).

CONCLUSIONS

Based on our findings, to identify TMJ involvement special attention should be paid to JIA patients with female gender, ANA positivity, and oligoarthritis, as well as those with a higher number of additional joints with active arthritis; and regular examinations of the TMJ should be performed.

Limited Mandibular Movements as a Consequence of Unilateral or Asymmetrical Temporomandibular Joint Involvement in Juvenile Idiopathic Arthritis Patients

This study aimed to assess the asymmetry of the lower face and motor dysfunction of the masticatory system resulting from unilateral or asymmetrical bilateral temporomandibular joint (TMJ) involvement in juvenile idiopathic arthritis (JIA) patients. The study consisted of clinical examination and cone beam computed tomography (CBCT) of TMJs. Statistical analysis showed correlations between several factors: facial asymmetry and mandibular lateral deviation; the direction of mandibular deviation and the degree of radiological deformities in TMJs; the child's age at the time of the onset and the range of lateral movement towards the healthy or less destructed joint. In addition, there was a significant difference in ranges of lateral movements; a significantly smaller range was observed for the joint with fewer condylar abnormalities compared to the range in the opposite direction. In JIA children, among the clinical markers of unilateral or asymmetrical TMJ involvement, the asymmetry of the lower face, deviation of the mandible on opening, and an uneven range of mandibular lateral movements deserve attention. The obtained results do not show a relationship between the degree of condylar changes and the asymmetry of the lower face and the presence and degree of mandibular motor dysfunction.

Alloplastic Temporomandibular Joint Reconstruction for Patients With Juvenile Idiopathic Arthritis

PURPOSE

The purpose of this study was to assess the efficacy of alloplastic temporomandibular joint (TMJ) total joint replacement (TJR) in patients with juvenile idiopathic arthritis (JIA).

MATERIALS AND METHODS

All patients with a formal diagnosis of JIA requiring a TMJ patient-specific TJR between 2010 and 2018 at The University of Texas-Health at San Antonio were retrospectively analyzed. To be included, patients must have had a formal diagnosis of JIA, complete records, and TMJ reconstruction with the TMJ Concepts patient-specific total joint prosthesis (TMJ Concepts, Ventura, CA). Clinical data acquisition was required at a minimum of 12 months after surgery (longest follow-up [LFU]). Subjective and objective analyses were performed using a 10-point visual analog scale at the preoperative and LFU time points. Surgical data at the perioperative and LFU time points were recorded for comparison.

RESULTS

Twenty patients with JIA met the inclusion criteria. The mean visual analog scale measurements for facial pain, TMJ pain, jaw function, diet, and disability were all significantly reduced at LFU. The maximal interincisal opening with pain was increased from 33.5 mm preoperatively to 44 mm at LFU, and the mean maximal interincisal opening without pain was increased from 31.1 mm preoperatively to 43 mm at LFU. None of the patients had complications from their TMJ TJR.

CONCLUSIONS

Alloplastic TMJ reconstruction is a safe and efficacious treatment option for the surgical management of end-stage TMJ disease in JIA patients.

Condylar alterations and facial growth in children with juvenile idiopathic arthritis

Purpose

The aim of this retrospective study was to evaluate facial growth in children with juvenile idiopathic arthritis (JIA) by means of lateral head cephalometric radiographs and relate the findings to temporomandibular joint (TMJ) condylar changes on panoramic radiographs.

Methods

Radiographic and medical records were evaluated in 65 children with JIA. Cephalometric and panoramic analyses were performed for the impact of condylar changes on facial growth. We compared children with condylar alterations, minor or major, with those without condylar alterations.

Results

Based on panoramic radiographs, no condylar alterations were seen in 27 of the 65 children and condylar alterations were seen in 38 children (i.e., 23 had minor and 15 major condylar alterations). The cephalometric analyses of the children with condylar changes showed significant growth disturbances with a more retrognathic mandible (SNB; p = 0.03), retruded chin position (SNPog; p = 0.02), larger mandibular angulation (ML/NSL; p = 0.009) and maxillary angulation (NL/NSL; p = 0.03) compared with children without condylar alterations. Children with minor condylar alterations had a significantly more retruded chin position (SNPog) than those with no condylar changes (p = 0.04).

Conclusions

Condylar changes in the TMJ, judged on panoramic radiography, in children with JIA, have impact on craniofacial growth. Even minor alterations seem to have an impact.

Disease activity and damage in juvenile idiopathic arthritis: methotrexate era versus biologic era

Objective

To compare the long-term disease state, in terms of activity and damage, of children with juvenile idiopathic arthritis (JIA) who had their disease onset in methotrexate (MTX) or biologic eras.

Methods

Patients were included in MTX or biologic era cohort depending on whether their disease presentation occurred before or after January 2000. All patients had disease duration ≥ 5 years and underwent a prospective cross-sectional assessment, which included measurement of disease activity and damage. Inactive disease (ID) and low disease activity (LDA) states were defined according to Wallace, JADAS10, and cJADAS10 criteria. Articular and extraarticular damage was assessed with the Juvenile Arthritis Damage Index (JADI).

Results

MTX and biologic era cohorts included 239 and 269 patients, respectively. Patients were divided in the “functional phenotypes” of oligoarthritis and polyarthritis. At cross-sectional visit, patients in the biologic era cohort with either oligoarthritis or polyarthritis had consistently higher frequencies of ID and LDA by all criteria. The measurement of disease damage at cross-sectional visit revealed that the frequency of impairment of > 1 JADI-Articular items was higher in MTX than in biologic era cohort (17.6% versus 11% in oligoarthritis and 52.6% versus 21.8% in polyarthritis). Likewise, frequency of involvement of > 1 JADI-Extraarticular items was higher in the MTX than in the biologic era cohort (26.5% versus 16.2% in oligoarthritis and 31.4% versus 13.5% in polyarthritis).

Conclusion

Our study provides evidence of the remarkable outcome improvement obtained with the recent therapeutic advance in JIA.

Main Oral Manifestations in Immune-Mediated and Inflammatory Rheumatic Diseases

Oral manifestations are frequent in patients with rheumatic diseases. The aim of this review is to offer readers practical advice concerning the onset, diagnosis and treatment of the main oral manifestations encountered in rheumatological and dental clinics. Signs and symptoms such as oral hyposalivation, xerostomia, temporomandibular joint disorders, periodontal disease, and dysphagia may be the first expression of a number of rheumatic diseases. Some of these manifestations are aspecific and very frequent, such as oral aphthosis, which can be the first manifestation in patients with systemic lupus erythematosus; some are potentially dangerous, such as jaw claudication during the course of giant cell arteritis; and some are very rare but peculiar, such as strawberry-like gingivitis in patients with granulomatosis with polyangiitis. Other oral manifestations are due to adverse reactions to disease-modifying anti-rheumatic drugs. Oral alterations in rheumatic diseases are frequently overlooked in clinical practice, but their prompt recognition not only allows the local lesions to be appropriately treated, but also makes it possible to identify an underlying systemic disease.

Temporomandibular joint involvement in children with juvenile idiopathic arthritis: a preliminary report

OBJECTIVE

Children with juvenile idiopathic arthritis (JIA) are at risk for temporomandibular joint (TMJ) arthritis. This can lead to pain, limited mouth opening, facial asymmetry, and malocclusion. Our objective was to characterize patients with JIA and TMJ involvement in a single center.

STUDY DESIGN

This was a retrospective study of children with JIA evaluated at Children's Healthcare of Atlanta. Inclusion criteria were confirmed JIA and jaw complaints. Medical records were reviewed to document demographics, JIA information, age at first TMJ complaint, and involvement of other joints. Descriptive statistics were computed.

RESULTS

Majority of patients were white (mean age 13 years; range 5-18 years) with polyarticular rheumatoid factor (RF) negative or oligoarticular persistent JIA. Some were antinuclear antibody (ANA) positive, RF positive, or human leukocyte antigen (HLA)-B27 positive. Patients had involvement of other joints (e.g., fingers, knees, wrists). Of those with TMJ symptoms, 6 (10%) had TMJ arthritis.

CONCLUSIONS

In our cohort, 60 (10%) of patients were diagnosed with TMJ arthritis. In this population, patients who are female, white, RF negative, HLA-B27 negative, ANA negative, and polyarticular RF-negative subtype and have involvement of other joints have a higher likelihood of having TMJ symptoms. If a patient meets these criteria, careful evaluation of TMJs should take place.

The role of imaging in juvenile idiopathic arthritis

INTRODUCTION

The prognosis of juvenile idiopathic arthritis (JIA) has changed dramatically due to the availability of novel drugs. Prompt diagnosis and treatment are essential to prevent permanent joint damage. As a result, methods to improve JIA diagnosis and prognosis are of high priority to tailor treatment strategies and maximize their efficacy. Musculoskeletal ultrasound and magnetic resonance imaging are more sensitive than clinical examination and radiography in the detection of joint involvement and might play a substantial role to optimize the management of JIA. Areas covered: This review compiles an inventory of potential uses of imaging studies in the modern practice of pediatric rheumatology, together with a critical analysis of the major challenges that are still to be addressed. Imaging appearance of normal growth-related changes of the musculoskeletal system will be discussed. Expert commentary: Knowledge of the evolving patterns of skeletal maturity is paramount to define pathological findings and avoid misinterpretations. Establishing a novel radiological algorithm for a rational use of imaging in JIA is of high priority to allow a speedier integration of imaging into the clinical workflow and decision-making process.

Risk Factors for Intraarticular Heterotopic Bone Formation in the Temporomandibular Joint in Juvenile Idiopathic Arthritis

Objective.

Intraarticular corticosteroid (IAC) injections are often used to treat temporomandibular joint (TMJ) arthritis associated with juvenile idiopathic arthritis (JIA). One potential complication of IA therapy is heterotopic bone formation (HBF). The purpose of our study was to evaluate risk factors for HBF development in children with JIA who received IA therapy for TMJ arthritis.

Methods.

This was a retrospective study of children with JIA who had received ≥ 1 IAC injection into the TMJ. Survival regression analysis was performed to identify risk factors for the development of HBF.

Results.

There were 238 children included, of whom 33 (14%) developed HBF. No cases of HBF were diagnosed prior to the initial injection. Univariate analysis revealed that the risk factors for development of HBF were the total number of injections received into the TMJ and age at diagnosis of JIA, while the length of time from diagnosis of JIA to the first injection was inversely associated with the risk of HBF formation. The total number of injections was no longer significant following adjusted survival models. Children with HBF had increased physical examination evidence of acute or chronic changes, namely decreased maximal incisal opening and increased likelihood of jaw deviation.

Conclusion.

HBF within the TMJ is relatively common in patients with JIA receiving IAC injections for TMJ arthritis. Future prospective studies are required to delineate the risks posed by the injections themselves as opposed to the underlying disease activity, as well as to evaluate alternative forms of local therapy to the TMJ.

Temporomandibular joint arthritis in juvenile idiopathic arthritis, now what?

BACKGROUND

Arthritis involving the temporomandibular joint (TMJ) complicates 40 - 96% of cases of juvenile idiopathic arthritis (JIA), potentially leading to devastating changes to form and function. Optimal evaluation and management of this joint remains a matter of ongoing discussion.

METHODS

We performed a PubMed search for all articles with keywords "temporomandibular" and "arthritis", covering the dates 2002 through February 28, 2018. A separate PubMed search was performed for all articles with keywords "temporomandibular joint", "arthritis", and "treatment" covering the same dates.

FINDINGS

The TMJ is a particularly challenging joint to assess, both clinically and with imaging studies. Clinical assessment of the TMJ is hampered by the low sensitivity of joint pain as well as the absence of physical exam findings early in the disease process. As with all joints, plain radiography and computed tomography only detect arthritic sequelae. Additionally, there is mixed data on the sensitivity of ultrasound, leaving magnetic resonance imaging (MRI) as the optimal diagnostic modality. However, several recent studies have shown that non-arthritic children can have subtle findings on MRI consistent with TMJ arthritis, such as joint effusion and contrast enhancement. Consequently, there has been an intense effort to identify features that can be used to differentiate mild TMJ arthritis from normal TMJs, such as the ratio of the enhancement within the TMJ itself compared to the enhancement in surrounding musculature. With respect to treatment of TMJ arthritis, there is minimal prospective data on medical therapy of this complicated joint. Retrospective studies have suggested that the response to medical therapy of the TMJ may lag behind that of other joints, prompting use of intraarticular (IA) therapy. Although most studies have shown short-term effectiveness of corticosteroids, the long-term safety of this therapy on local growth as well as on the development of IA heterotopic bone have prompted recommendations to limit use of IA corticosteroids. Severe TMJ disease from JIA can also be managed non-operatively with splints in a growing child, as well as with surgery.

CONCLUSION

In this review, we summarize literature on the diagnosis and management of TMJ arthritis in JIA and suggest a diagnostic and therapeutic algorithm for children with refractory TMJ arthritis.

Normal magnetic resonance appearances of the temporomandibular joints in children and young adults aged 2-18 years

BACKGROUND

Knowledge of normal appearances of the temporomandibular joint (TMJ) is paramount when assessing the joint for disease in juvenile idiopathic arthritis. Reliable features defining normal TMJs in children are limited.

OBJECTIVE

To establish reliable normal standards for the TMJ at magnetic resonance imaging (MRI).

MATERIALS AND METHODS

We included children and young adults aged 2-18 years undergoing a head MRI for reasons not believed to affect the TMJs. We assessed TMJ anatomy and contrast enhancement using a high-resolution 3-D T1-weighted sequence. We noted joint fluid and bone marrow oedema based on a T2-weighted sequence. Three experienced radiologists read all examinations twice in consensus and defined intraobserver consensus agreement.

RESULTS

We evaluated the TMJs in 101 children and young adults (45 female), mean age 10.7 years (range 2-18 years). The intraobserver consensus agreement for the assessment of anterior condylar inclination in the sagittal/oblique plane was moderate to good (Cohen κ=0.7 for the right side). Cohen κ for intraobserver consensus agreement for condylar shape in the coronal plane on a 0-2 scale was 0.4 for the right and 0.6 for the left. Intraobserver agreement for measurement of joint space height and assessment of bone marrow oedema was poor. There was a statistically significant increase in anterior inclination by age in the sagittal plane on a 0-2 scale (P<0.0001). Eighty percent of the condyles showed a rounded shape in the coronal plane while 20% showed mild flattening. Thirty-five of 36 right TMJs showed contrast enhancement (mild enhancement in 32 joints, moderate in 3 joints).

CONCLUSION

Subjective assessment of the anterior condylar inclination in the sagittal/oblique plane and condylar flattening in the coronal plane can be considered precise features for describing TMJ anatomy in healthy children. There is an increasing anterior inclination by age. Mild contrast enhancement of the TMJs should be considered a normal finding.

Isolated Arthritis of the Temporomandibular Joint as the Initial Manifestation of Juvenile Idiopathic Arthritis

OBJECTIVE

To describe characteristics of patients with juvenile idiopathic arthritis (JIA) presenting with isolated arthritis of the temporomandibular joints (TMJ).

METHODS

Patients with JIA with isolated TMJ arthritis from 4 large tertiary pediatric rheumatology centers were included. Demographic and clinical data were analyzed using descriptive statistics.

RESULTS

Fifty-five patients were identified (65% bilateral presentation). Six patients developed arthritis in other joints (median time 6 mos); 4 patients developed uveitis, all prior to arthritis. At last followup, 9% were still taking antirheumatic medications.

CONCLUSION

JIA TMJ arthritis can occur in isolation, and is probably underdiagnosed. Care providers including dentists and orthodontists should be aware of this presentation.

Quantifying Temporomandibular Joint Synovitis in Children With Juvenile Idiopathic Arthritis

OBJECTIVE

Juvenile idiopathic arthritis (JIA) frequently affects the temporomandibular joints (TMJs) and is often undetected by history, examination, and plain imaging. Qualitative assessment of gadolinium-enhanced magnetic resonance images (MRIs) is currently the standard for diagnosis of TMJ synovitis associated with JIA. The purpose of this study is to apply a quantitative analysis of synovial enhancement to MRIs of patients with and without JIA to establish a disease threshold and sensitivity and specificity for the technique.

METHODS

This is a retrospective case-control study of children (age ≤16 years) who had MRIs with gadolinium including the TMJs. Subjects were divided into a JIA group and a control group. From a coronal T1-weighted image, a ratio (enhancement ratio [ER]) of the average pixel intensity within three 0.2-mm² regions of interest (ROIs) in the TMJ synovium to that of a 50-mm² ROI of the longus capitis muscle was calculated. Receiver operating characteristic curves were used to determine the sensitivity and specificity. The inter- and intraexaminer reliability was evaluated with Bland-Altman plots and 2-way mixed, absolute agreement intraclass correlation coefficients.

RESULTS

There were 187 and 142 TMJs included in the JIA and control groups, respectively. An ER threshold of 1.55 had a sensitivity and specificity for detecting synovitis of 91% and 96%, respectively. The inter- and intraexaminer reliability was excellent.

CONCLUSION

Calculating a ratio of pixel intensity between the TMJ synovium and the longus capitis muscle is a reliable way to quantify synovial enhancement. An ER of 1.55 differentiates normal TMJs from those affected by inflammatory arthritis.

Temporomandibular joint involvement in childhood arthritis: comparison of ultrasonography-assessed capsular width and MRI-assessed synovitis

OBJECTIVES

Ultrasonography is an effective, low-cost, low-threshold and convenient diagnostic tool in childhood arthritis, but its value in temporomandibular joint (TMJ) involvement is not clear. The purpose of our study was to explore the reliability of ultrasonography to assess TMJ inflammation using contrast-enhanced MRI as reference standard, in order to deduce cut-off values for TMJ capsular width to detect enhanced synovial thickening (synovitis).

METHODS

124 ultrasonography and MRI examinations in 55 patients [mean age 12.4 ± 3.5 years (±standard deviation)], the majority obtained within 1 day, were scored for subcondylar and condylar capsular width (ultrasonography images) and amount of synovitis (MR images). The correlations of these findings were calculated. A receiver operating characteristic (ROC) curve analysis, with MRI findings as reference standard, was obtained.

RESULTS

The correlation between ultrasonography-assessed capsular width and MRI-assessed amount of synovitis was moderate both at the subcondylar and condylar level [Spearman's rho (ρ): 0.483; p < 0.001 and 0.347; p < 0.001 respectively]. The ROC curve indicated the best discriminatory ability at the subcondylar level with an area under the curve of 0.77 (95% confidence interval 0.69-0.85) and a cut-off value of 1.2 mm (sensitivity 72%, specificity 70%) for the capsular width.

CONCLUSIONS

A moderate correlation between ultrasonography-assessed capsular width and MRI-assessed synovitis was found in childhood arthritis with the best discriminatory ability at the subcondylar level. This indicates that ultrasonography may be a valuable diagnostic tool in the initial assessment of TMJ inflammation.

Quantifying the Effect of Temporomandibular Joint Intra-Articular Steroid Injection on Synovial Enhancement in Juvenile Idiopathic Arthritis

PURPOSE

To quantify the effect of intra-articular steroid injections (IASIs) on temporomandibular joint (TMJ) synovitis in children with juvenile idiopathic arthritis (JIA) using gadolinium-enhanced magnetic resonance imaging (MRI).

MATERIALS AND METHODS

The present study was a retrospective study of children with JIA who had undergone TMJ IASIs at Boston Children's Hospital. The patients were included if they had undergone contrast-enhanced MRI both before and after IASI and if the pre-IASI MRI had demonstrated synovitis (enhancement ratio [ER] >1.55). Patients with TMJ pathology or pain unrelated to JIA or a history of facial trauma were excluded. The predictor variables were age, gender, JIA subtype, exposure to medications for arthritis, and a family history of autoimmune disease. The primary outcome variable was the ER. Additional outcome variables included patient-reported pain and the maximal incisal opening (MIO).

RESULTS

Twenty-nine subjects (83% female) with a total of 50 injected TMJs were included. The average age at JIA diagnosis and at IASI was 6.8 ± 1.7 years and 12.1 ± 1.9 years, respectively. The mean follow-up period was 22.9 ± 4.3 months (range 5 to 48). The ER decreased in all injected joints, with a mean reduction of 1.05 ± 1.01 (P < .001). The post-IASI ER was less than the normal threshold (1.55) in 18% of the injected TMJs. IASI was associated with an elimination of pain in 89% of the subjects (P < .001) and in augmentation of the MIO by 5.8 ± 2.6 mm (P < .001).

CONCLUSIONS

In children with JIA and TMJ synovitis, TMJ IASI was associated with a reduction in synovial enhancement, decreased pain, and an increased MIO. Only 18% of injected joints, however, experienced complete resolution of synovitis. These results support the use of IASI in the management of the pain and dysfunction associated with TMJ synovitis. Further study is required to determine the efficacy of IASI in limiting inflammation and future joint destruction.

Contemporary management of TMJ involvement in JIA patients and its orofacial consequences

Juvenile idiopathic arthritis is the most common chronic rheumatic condition during childhood. Temporomandibular joint arthritis is frequently asymptomatic. When it takes place during childhood, it may affect condylar growth; therefore, these children are at risk of unfavorable long-term outcomes from the associated joint damage. The etiology is not completely understood, but it is considered as multifactorial with both genetic and environmental factors involved.

The standardized examination and imaging protocols serve important purpose to diagnose temporomandibular joint (TMJ) arthritis not only to establish an early interventional strategy but also to assess craniofacial growth and the progression of signs and symptoms in those patients. Although the treatment of juvenile idiopathic arthritis (JIA) has changed dramatically over the last decades due to new therapeutic options, TMJ arthritis still can develop during the course of the disease. In clinical experience, TMJs appear to respond less well to the standard of care used to treat other joints. More individualized approach to the patient’s treatment serves as the main goal of personalized medicine. It could be achieved by adopting new methods of medical imaging such as conebeam computer tomography as well as developing reliable biomarkers which may assist with predicting disease type, course, or severity and predicting response to medication.

This article provides an overview of current information on orofacial complications in JIA and its management. Based on information provided in this review, more precise diagnosis, proper tools for recognizing people at risk, and more efficient treatment approaches could be implemented. This may lead to more personalized treatment management strategies of TMJ complications of JIA patients.

Disk abnormality coexists with any degree of synovial and osseous abnormality in the temporomandibular joints of children with juvenile idiopathic arthritis

BACKGROUND

MRI manifestation of temporomandibular joint arthritis is frequently reported in children with juvenile idiopathic arthritis. However, little attention has been paid to temporomandibular joint disk abnormalities.

OBJECTIVE

To assess combinations of MRI findings in the symptomatic temporomandibular joint in children with juvenile idiopathic arthritis with focus on disk abnormalities.

MATERIALS AND METHODS

This was a retrospective study of 46 patients with juvenile idiopathic arthritis, mean age 12 years (range: 5-17 years). Mean disease duration was 70 months (standard deviation: 61 months). MR images of 92 temporomandibular joints were scored for thickness of abnormally enhancing synovium (synovitis), joint effusion, bone marrow oedema, abnormal bone shape, bone erosion and disk abnormalities.

RESULTS

The 92 temporomandibular joints were categorized as A: No synovitis and normal bone shape (30/92; 33%), B: Synovitis and normal bone shape (14/92: 15%), C: Synovitis and abnormal bone shape (38/92; 41%) and D: No synovitis but abnormal bone shape (10/92; 11%). Thirty-six of the 46 patients (78%) had synovitis and 33/46 (72%) had abnormal bone shape, most frequently in combination (30/46; 65%). Disk abnormalities (flat disk, fragmented disk, adherent disk and displaced disk) were found in 29/46 patients (63%). Disk abnormalities were found in all categories of juvenile idiopathic arthritis involved temporomandibular joints (B: 8/14 [57%]; C: 25/38 [66%] and D: 7/10 [70%]). Disk displacement was found in half of the joints (7/14) in category B. Synovitis was most pronounced in this category.

CONCLUSION

Disk abnormalities were frequent. Disk displacement also occurred in joints with early temporomandibular joint arthritis, i.e., with normal bone shape. Other disk abnormalities were found in joints with bone abnormalities. Attention should be paid to disk abnormalities both in early and long-standing temporomandibular joint arthritis in children with juvenile idiopathic arthritis.