Human histologic tissue response after long-term orthodontic tooth movement

The maxilla of a deceased 19-year-old young woman who had been treated with an edgewise appliance was removed during autopsy. The specimen was prepared histologically in the horizontal plane. The type of tooth movement was reconstructed by comparing the treatment documents at outset (photograph of dental cast, radiograph) with the photograph and radiographs of the specimen. This permitted the histological findings to be correlated to the type of tooth movement. Results: the localization and extent of tissue changes at the roots depend on the type of tooth movement and the structure of the bone. In case of an atrophied alveolar bone in front of the tooth movement direction, a partial increase of osseous tissue may be induced by bone apposition in the subperiosteal layer. After tooth movement in the maxillary sinus region, however, bone resorption was found in the subperiosteal layer in front of the roots. The histologic findings are more pronounced than the radiographs would suggest. Histologically verified bony dehiscences or fenestrations in the facial or oral cortical plate could not be diagnosed by macroscopic inspection of the specimen. (A M J O RTHOD D ENTOFAC O RTHOP 1995;107:360-71.)