Last Updated: 2007-10-22 16:42:43 -0400 (Reuters Health)

NEW YORK (Reuters Health) – Temporomandibular joint (TMJ) condylar damage leading to alterations in the craniofacial profile is common in patients with juvenile idiopathic arthritis (JIA), according to Belgian researchers.

"Our data clearly demonstrate that TMJ involvement and condylar damage are very frequent and can occur in every child with JIA, irrespective of subtype," senior investigator Dr. Carine Wouters told Reuters Health.

"Condylar damage may be present early in the disease course, progress even in the absence of clinical symptoms or signs, and lead to profound changes in craniofacial morphology."

In the September issue of the Journal of Rheumatology, Dr. Wouters of University Hospitals K.U. Leuven and colleagues report on their study of 100 patients with various subtypes of JIA.

Overall, 55 of the patients had a least one sign or symptom of TMJ arthritis. Restricted mouth opening was the most frequent clinical finding and was seen in 28 patients.

Of the 46 patients who underwent radiographic examination, 36 (78%) showed condylar damage. This was not tied to factors such as clinical orthodontic findings or disease severity or duration.

Differences between the JIA patients and age-matched controls included larger mandibular plane angles and greater anterior facial height. The craniofacial alterations were clearly related to condylar damage, say the investigators, "even when present to a minor degree."

Thus, continued Dr. Wouters, "early recognition of these changes is important for orthodontic diagnosis and treatment planning. We propose that clinical follow-up of every JIA patient should include regular evaluation by an orthodontist and imaging of the TMJ."

"The question as to which is the appropriate imaging technique for early detection of TMJ arthritis," she concluded, "is to be addressed by further studies."

J Rheumatol 2007;34:1925-1933.