Ankylosis. Part I: Etiology, a look at the problem
Tooth ankylosis can be diagnosed in several ways:
Lack of mobility or a distinct, stable sound when percussing with a hand tool (as a rule, this method is reliable only when at least 20 percent of the root is affected)
The incisal or occlusal margin is apical to the incisal / occlusal plane
Marginal gums and enamel-cement joints are in a more apical position compared to adjacent teeth
An X-ray examination reveals obliteration of the periodontal gap
So why does tooth ankylosis cause concern?
The first reason is that the ankylosed root is constantly resorbed and replaced with bone tissue, thus reducing tooth support. Although the rate of resorption can be extremely variable.
The second – the presence of an ankylosed tooth during the period of growth of the jaw affects the normal development of the alveolar process. An ankylosed tooth will look as if it plunges into the alveolar bone when teething adjacent teeth.
There are several theories of the etiology of dental ankylosis:
Violation of local metabolism in the periodontal ligament (Biederman: 1962)
Genetics (Kural, Magnusson: 1984)
Temporary teeth in the absence of rudiments of permanent teeth (Brearly, McKibben: 1972)
Of course, the most common theory about the cause of ankylosis is traumatic damage to the periodontal ligament (Kracke: 1975, Henderson: 1979, Andreasen: 1981). The risk of ankylosis is highest for teeth with subluxations or traumatic injuries, as this affects the nature and severity of damage to the periodontal ligament.
Temporary teeth are ankylosed much more often than permanent ones. Their ratio exceeds 10: 1. Lower teeth are ankylosed more than twice as often as upper teeth.
Despite the fact that the initial treatment upon detection of an ankylosed tooth often consists in its immediate removal, the final decision on treatment should be made only after evaluating a number of different factors:
Is ankylosed tooth temporary or permanent
Patient age / ankylosis onset
The location of the affected tooth
In subsequent articles, various recommendations and treatment options will be considered taking into account the variety of clinical data that may be present with this pathology.