Endochondral ossification of the spheno-occipital synchondrosis: juvenile idiopathic arthritis vs healthy patients

AIM: The aim of this study is to evaluate, by Cone Beam Computerized Tomography (CBCT), any discrepancy about the age range of the complete ossification of the spheno-occipital suture, comparing a sample of patients with Juvenile Idiopathic Arthritis (JIA +) with a sample of healthy patients (AIG-). MATERIALS AND METHOD: We analyzed 140 CBCT of Juvenile Idiopathic Arthritis patients (JIA +) between the ages of 4 and 25 years treated at the Department of Orthodontics, University of Milan, and compared with the results of a sample of 230 healthy patients (AIG-) aged between 5 and 25years being treated in the same department. All the patients have already had the TC we evaluated in this study because of the diagnosis of condylar disease (AIG+) or for the cephalometric evaluation .Sections obtained were studied in three planes of space through the use of dedicated software for the three-dimensional volumetric reconstruction. According to the radiographic images observed, were divided into two groups: the first one in which there is a complete spheno-occipital ossification, characterized by the absence of radiolucent band separating the two bones considered; a second one in which is not observed bone fusion. RESULTS: Direct observation of three-dimensional images available to us shows that: in subjects AIG + no female patient presents complete spheno-occipital ossification before 10 years and no male patient has the same ossification before the 11 years. Also is noted that no female subject has incomplete ossification after 15 years or any male subject after the age of 13. CONCLUSIONS: The results we obtained from this study allow us to say that considering female groups we observed comparable data in the two samples analyzed; instead in male groups there are slight differences. We can affirm that both juvenile idiopathic arthritis and its therapy does not significantly change the growth of the cranial base or the mean age ossification of spheno-occipital suture.