Scanning electron microscopy of teeth in osteogenesis imperfecta type I.

Opalescent teeth from five patients and nonopalescent teeth from six patients with osteogenesis imperfecta type I were examined with the scanning electron microscope and their appearances compared with those of teeth from normal persons. In opalescent teeth the main findings were a reduction in the number and variation in the size of the dentinal tubules that were irregularly embedded within the disturbed dentinal matrix and an abnormally smooth enamel-dentinal junction. Similar less marked dentinal abnormalities were found in the nonopalescent teeth from three patients. No abnormality was found in the enamel in any of the teeth examined. These findings suggest that in osteogenesis imperfecta teeth that appear normal may have defective dentine. This relevant to the current clinical classification of the disorder into subgroups according to the clinical presence or absence of affected teeth.