Incidence of the small dens in dente

Abstract

The term dens in dente in the past has referred to a markedly malformed tooth in which an invagination has occurred. If one accepts the definition o f Kitchin1 that a dens in dente is the result of maldevelopment of a single tooth because of an abnormal invagination and subsequent degree of enclosure o f tooth substance normally confined to an outside surface, then it becomes evident that there is only a difference in degree between the classi­ cal dens in dente, as exemplified by the distorted tooth in Figure 1, left, and the normally-shaped tooth in Figure 1, right. The latter tooth, no less than the former, has an enclosure o f tooth substance nor­ mally confined to an outside surface and therefore is as much a dens in dente as the example in Figure 1, left. This anomaly is so rare that it was not until 1947 that a case of bilateral dens in dente was reported in the literature. Since that time I have been able to find reference to only three other such cases, the last one reported by T oto2 in 1953. Hine,3 however, considered the small, expanded invagination to be a dens in dente and in 1936 prepared an exhibit demonstrating the gradations of invagi­ nations from the shallowest of lingual pits through the small dens in dente in this study to the huge deformed invaginations which were once thought to be the only dens in dente. Atkinson4 also considered the small invagination to be dens in dente, and in 1943 in a roentgenographic survey o f 500 patients found that 10 per cent were so affected. He did not specify, however, just what constituted his requirements. Shafer5 in 1953 in a roentgenographic survey o f patients edentulous and other­ wise found that 1.3 per cent showed clear evidence of expanded invaginations. Also in 1953 Hallett6 examined roent­ genograms o f 586, orthodontic patients whose ages ranged from 2 to 15. He found an incidence of 6.6 per cent of what he termed Class III and Class IV palatal invaginations of the incisors, which were expanded invaginations. He preferred to restrict the term dens in dente to the large invaginations.