[Histological study of periodontal healing of surgically displaced human teeth].

Mandibular incisors had to be extracted on a 52 years old patient. The aim of this investigation was to study, the periodontal healing of teeth surgically displaced after bone resections (alveolar, buccal and apical). 3 years later, the teeth were extracted and treated for microscopic observation. No new attachment was seen on the curetted roots, except where the periodontal ligament had been preserved. The concept of cellular sociology was suggested to explain the sites of radicular resorption. An hypothesis was then put forward: epithelial formations present in the periodontal ligament are not of an embryologic origin (Malassez debris) but are issued from the migration of epithelial cords during new formation of the junctional epithelium.