[Periodontal considerations related to extractions].

During any tooth extraction, the dentist has to think about healing problems in order to maintain as much bone as possible afterwards. Careful and well done extractions using classical techniques allow maximum bone preservation in normal cases. At minima alveolectomy techniques are a guarantee against tremendous bone loss. After healing and before prosthetic rehabilitation, crests must be checked and, if necessary, corrected by one of the several available techniques.