[Limitations of intrusion of periodontally involved maxillary buccal teeth for furcation treatment].

In a study on three dogs 12 two-rooted premolars with reduced periodontia were intruded to reestablish marginal attachment. In eight roots intrusion into the basal cortical bone of the nasal sinus was found. The histological findings showed that in these cases a possible gain of new attachment in the interradicular space may be impaired by a loss of bone support in those sites where the root intruded into the sinus. The greater the extent of intrusion into the sinus the higher the expected loss of periodontal attachment.