Hypodontia and hypoplasia of mandible: A rare defect caused by combination therapy.

Hypodontia is defined as the developmental absence of one or more tooth and it can present in varying degrees of severity and severe hypodontia has been defined as the absence of six teeth, excluding third molars. Radiation plays an important role in the treatment of head and neck cancer, in spite of its benefits, radiation has several side-effects in the head and neck region. This article highlights a case report, where hypodontia, hypoplasia of mandible, stunded permanent teeth roots, microdontia, inversion of tooth bud were observed in 19 years old patient who was diagnosed with Langerhans cell histiocytosis at her age of 3 years she had received a combination of radiotherapy and chemotherapy for a period of 1 year and radiation of 50 Gy was used in the head and neck region. Radiographs were taken and it revealed abnormal changes in growth and development of bone and teeth.