Cranial structure and condylar asymmetry of patients with juvenile idiopathic arthritis: a risky growth pattern

The aim of the study was to evaluate the cephalometric differences and condylar asymmetry between patients with juvenile idiopathic arthritis (JIA) and normal control group. Sixty-two JIA patients with a latero-lateral cephalogram and orthopantomography, seeking for orthodontic therapy, and 62 normal matched subjects were comprised in the study. Cephalometric analysis was used for the evaluation of facial morphology while the method of Habets et al. (J Oral Rehabil 15(5): 465-471, 1988) was used to compare the condyles in orthopantomography. The significance of between-group differences was assessed using the Mann-Whitney test, as appropriate. The results showed a prevalence of the upper maxilla with hypomandibulia (class II), hyperdivergency with short vertical ramus posterior and posterior rotation of the mandible in JIA children (SNB, ANB, NSL/ML, Fh/ML, NL/ML, ArGo, ML P < 0.0001, ML/Oc P < 0.004, ArGo/GoGn P = 0.02, no difference for SNA). The condyles of the JIA group resulted highly asymmetric (P < 0.0001). The growth pattern of JIA patients resulted clearly different from normal subjects. This serious impairment of the cranial growth may be considered as an indicator of the need for early and continuous orthognatodonthic therapy during the entire period of development for all JIA patients, independently from temporomandibular joint signs or symptoms. To this end, it is important that rheumatologists and orthognathodontists set up a multidisciplinary treatment planned to control the side effects of a deranged growing pattern, to strictly avoid any orthodontic therapies that may worsen function and growth, and to promote treatments improving the physiology and biology of the cranial development.