title: Implants placed in immediate extraction sites: a report of histologic and histometric analyses of human biopsies.
abstract: Five titanium plasma-sprayed implants were biopsied from a human volunteer 6 months after placement. Four test implants had been placed in immediate extraction sockets, while one implant was placed in a mature site and served as a control. The histologic analysis demonstrated that all five implants achieved osseointegration as demonstrated by light microscopy, whereas a varying degree of bone-implant contact was observed. The non-loaded control implant had the highest percentage of bone-implant contact, 72%, followed by the two implants placed in the canine sites presenting with a horizontal defect dimension of 1.5 nm or less. These implants were placed without a barrier membrane, but in a submerged fashion. The histometric analysis showed a mean bone-implant contact of 50% for these two implants. The lowest mean bone-implant contact (17%) was observed for the two molar implants, which had horizontal defect dimensions of 4 mm; these implants were placed in a non-submerged fashion with the implants perforating an expanded polytetrafluoroethylene membrane. The authors concluded that osseointegration may occur in immediate extraction sites in humans using titanium implants with a plasma-sprayed surface. The horizontal component of the peri-implant defect was apparently the most critical factor relating to the final amount of bone-implant contact.
authors.affiliation: Department of Oral Surgery, School of Dental Medicine, University of Berne, Switzerland.
authors.forename: T G
authors.initials: TG
authors.lastname: Wilson
authors.forename: R
authors.initials: R
authors.lastname: Schenk
authors.forename: D
authors.initials: D
authors.lastname: Buser
authors.forename: D
authors.initials: D
authors.lastname: Cochran
mesh_terms: D000539:Alveolar Process / Q000473:pathology; D001861:Bone Regeneration; D016025:Bone Transplantation; D003481:Cuspid; D003758:Dental Implantation, Endosseous / Q000379:methods*; D006801:Humans; D008297:Male; D008567:Membranes, Artificial; D008875:Middle Aged; D008963:Molar; D016348:Osseointegration; D013499:Surface Properties; D014081:Tooth Extraction
chemical_list: D008567:Membranes, Artificial