HISTOLOGIC-CHANGES IN DENTAL MORPHOLOGY INDUCED BY HIGH-DOSE CHEMOTHERAPY AND TOTAL-BODY IRRADIATION

Disturbances in dental development were studied with the use of radiog raphy and histology in a patient with acute lymphoblastic leukemia who was treated with induction chemotherapy at 2.3 years of age and bone marrow transplantation at 4.3 years of age. The follow-up 9.5 years af ter bone marrow transplantation showed evidence of short tapered roots , enamel hypoplasia, microdontia, and aplasia. A histologic examinatio n of two extracted permanent teeth showed that the crown of the maxill ary lateral incisor exhibited numerous incremental lines that correspo nded closely to the treatment periods with cytotoxic drugs. The maxill ary second premolar exhibited regularly spaced incremental lines in th e enamel and dentine. A gross hypoplasia was seen in the cervical part of the crown corresponding to the time of administration of 10 Gy tot al body irradiation. The results indicate that chemotherapy mainly ind uces qualitative disturbances in dentine and enamel, whereas total bod y irradiation induces both qualitative and quantitative changes.