Radiographic study of bone loss of mandibular lingual cortical plate accompanied by third molar development

Objective. The purpose was to determine the features of mandibular lingual cortical bone loss around the root of the mandibular third molar. Study design. We examined occlusal radiographs in 2210 persons aged 11 to 78 years. Results. Prominent increase of incidence of bone loss was evident in subjects in their third decade compared with those in their second decade. The incidence was not decreased into the sixties. The incidence of bone loss in men was significantly higher than that in women. The incidence was not influenced by inflammation around the tooth crown of the third molar, by tooth caries, or by metal fillings present in the third molar. Conclusions. The present observations suggest that bone loss is induced by physiologic processes that accompany root formation of the third molar after mandibular growth.