An unusual case of hereditary fibrous osteodysplasia (fragilitas ossium) with replacement of dentine by osteocementum

Abstract

Unique dental pathology has been reported in a case of hereditary fibrous osteodystrophy, which was thought consistent with some stage of fragilitas ossium. Ten teeth were studied all of which showed extensive resorptive processes affecting primarily the dentine, but also involving the cementum. This resorption which in some instances removed almost the entire root of the tooth, was repaired by trabeculated osteocementum causing a complete change in the histologic appearance of the tooth.Two interesting conclusions can be drawn from the histologic study of these teeth. The first is that teeth may resorb in a similar way as bone, and therefore the fact that they are not involved in hyperparathyroidism is not because they are immune to resorption. The second conclusion concerns the genesis of osteoclasts. The fact that osteoclasts appear in dentine which contains no enclaved cells should disprove the theory that they are a conglomeration of liberated bone corpuscles.