January 12, 2014
Ankylosis is a term for a dental condition where a tooth looses its normal ligament connection to the bone and becomes fused directly to the alveolar bone. It can occur in primary (deciduous, baby) teeth and permanent (adult) teeth. Normally there is a soft tissue situated between the teeth roots and the bone called periodontal ligament which consists of connective tissue (mostly fibers). When ankylosis occurs this space is being filled with cementum that connects the bone to the root. Therefore the tooth stops erupting and stays in the same position.This is a fairly common occurence and it’s most often seen in first and second deciduous molars.
The diagnosis of ankylosed teeth requires full dental anamnesis and proper x-rays. Clinically these teeth appear like they are not erupting or they are sinking into the gum tissue. In some cases, the ankylosed tooth may completely disappear and be covered up with gum tissue.
When a primary tooth becomes ankylosed some problems result. When the tooth root fuses to the bone it no longer grows out of the normal rate with the other teeth. Because of this it appears submerged compared with the other teeth. Second, the upper teeth need the lower teeth for support. With the tooth submerged the opposing upper tooth grows out of the socket and also looses its normal allignment. The third and more serious problem has to do with the roots of the ankylosed tooth. About 50% of the time the roots of the ankylosed teeth fail to normally dissolve as the permanent tooth grows in and the permanent tooth is blocked out of position. As a result, this may cause significant problems in eruption, often with severe bone loss and migration of deciduous and permanent teeth.
The solution of these problems is the eventual removal of the ankylosed tooth by an oral surgeon. Strong indications for extraction are the significant submergence of the ankylosed teeth and the change in the axial inclination of the adjacent teeth.The dentist should work with the parents and the child in order to determine the best timing for the extraction of the ankylosed tooth. Early consultation with an orthodontist is necessary in order to monitor teeth eruption and prevent space closure, bone loss and jaw distortion.