Why is there an increased incidence of TMJ ankylosis in children compared to adults?

TMJ ankylosis occurs when there is an abnormal fusion of the bones in the temporomandibular joint, leading to restricted movement of the jaw. In children, the incidence of TMJ ankylosis is increased due to a combination of developmental factors and greater vulnerability to conditions that predispose to this condition.

The correct answer highlights the role of thin cortical bone in children. Children's bones are still forming and have not reached their maximum density, which makes them more susceptible to changes caused by trauma or disease. The thinner cortical bone can lead to inadequate support for the joint, thereby increasing the risk of conditions such as ankylosis when injuries occur or when there is a pathological process at play. This anatomical and physiological immaturity contributes significantly to their predisposition to TMJ disorders compared to adults, whose bones are generally more robust and resilient due to full maturation.

Understanding this aspect is crucial for grasping why younger individuals might have a higher tendency for TMJ complications, guiding clinicians in both treatment and preventive strategies in pediatric populations.