Congenital prearticular temporo-mandibular ankylosis in two siblings.

A report of congenital ankylosis of the temporo-mandibular joint has only very rarely been published. The existence of this entity has been met with great scepticism and therefore believed to be due to perinatal trauma and subsequent development of the ankylosis. However, publications are now available of observations at birth after an uneventful pregnancy and spontaneous delivery. Our cases are the first publication of congenital TMJ ankylosis in two siblings, although there are hints in the histories in two other papers that a sibling may have suffered from the same condition. We discuss the hypothesis that the potential to ankylose in the temporomandibular area is a congenital disorder as in our cases, and that even later in life trauma or infection are only supervening initiating factors.