Clinically Established Temporomandibular Involvement in Adults With Juvenile Idiopathic Arthritis.

OBJECTIVE: To study clinical variables defining temporomandibular function in adults with juvenile idiopathic arthritis (JIA) and healthy controls. METHODS: In this cross-sectional study, the temporomandibular joint (TMJ) screening protocol, mandibular range of motion (MROM), and anterior maximum voluntary bite force (AMVBF) were compared between adults with JIA and healthy controls. Unadjusted and adjusted models with corrections for sex and disease duration were constructed for active maximum interincisal mouth opening (AMIO) and AMVBF. RESULTS: A total of 100 adults with JIA and 59 healthy adults were included in this study. In adults with JIA, 56% had clinically established TMJ involvement. AMIO was the MROM variable most reduced by TMJ involvement; AMIO was 8.8 mm (95% CI -11.40 to -6.12; P < 0.001) less in adults with JIA with TMJ involvement compared to JIA without TMJ involvement. No differences of AMIO were found between healthy adults and adults with JIA without TMJ involvement (-2.52, 95% CI -5.13 to 0.10; P = 0.06). Male sex was associated with a higher AMIO, and disease duration was associated with a decreased AMIO. Collinearity between the subtype prebiologic era and disease duration was found. AMVBF did not differ between adults with JIA and healthy adults. CONCLUSION: The high prevalence of clinically established TMJ involvement in adults with JIA indicates the need for awareness of TMJ problems in adults with JIA. TMJ involvement negatively influenced AMIO and should therefore be part of the TMJ screening in adults with JIA. AMVBF seems to have less utility for TMJ screening in adult populations.

Reliability and measurement error of anterior maximum voluntary bite force in children with juvenile idiopathic arthritis and healthy children.

In children with juvenile idiopathic arthritis (JIA) the temporomandibular joint (TMJ) can be involved. As a consequence, the oral function can be impaired due to joint and/or muscle involvement of the masticatory system with a negative influence on the maximum bite force. The aim of this cross-sectional study was to establish the reliability of AMVBF in children with JIA and healthy children. Children with JIA and healthy children conducted three attempts of AMVBF. The reliability of AMVBF measurement was determined by the intra-class correlation coefficient (ICC) by age, standard error of measurement (SEM), smallest detectable change (SDC), and limits of agreement (LoA). A total of 298 children with JIA and 168 healthy children were examined. The AMVBF measurements showed an good to excellent reliability in children with JIA based on the ICCs corrected for age (0.782-0.979). In healthy children, the reliability was moderate to excellent (0.546-0.999). The SDC in our study indicated that values above 11.4N might be a clinical relevant change over time in children with JIA. The LoA showed a wide spread of variability in both children with JIA (-72.6-44.4N) and healthy children (-79.9-72.8N). The Bland-Altman plots indicated that the differences between the test and retest increased in value proportionally to the biteforce value.

Growth curves for mandibular range of motion and maximum voluntary bite force in healthy children.

Mandibular range of motion and bite force are indispensable variables for the evaluation of mandibular function. There are a variety of medical and dental conditions that can negatively affect mandibular function. Values for mandibular range of motion (i.e., active and passive maximum interincisal mouth opening, protrusion, and laterotrusion) and anterior maximum voluntary bite force (AMVBF) in healthy children and adolescents can help in recognizing temporomandibular dysfunction. In this longitudinal study, 169 healthy children aged 6-18 years were included. They were examined at four time points over 1 year. Mixed model analysis was performed to produce growth curves of mandibular range of motion and AMVBF. Average active maximum interincisal mouth opening was significantly higher in boys with 50.0 mm compared to 47.8 mm in girls. Boys also had a significantly higher AMVBF than girls with an average of 169.0 N versus 140.0 N, respectively. Growth curves of active and passive maximum interincisal mouth opening showed an increase with age, albeit levelling off through puberty. The growth curves of AMVBF in girls reach a plateau phase at ages 12-14 years, after which the curve descends; in boys, the AMVBF tended to increase up to 18 years of age, although a slow-down after 14 years of age was noted.

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.