title: Hard tissue formation adjacent to implants of various size and configuration immediately placed into extraction sockets: an experimental study in dogs.
abstract: OBJECTIVE
  To evaluate the influence of implant size and configuration on osseointegration in implants immediately placed into extraction sockets.
  
  
  METHODS
  Implants were installed immediately into extraction sockets in the mandibles of six Labrador dogs. In the control sites, cylindrical transmucosal implants (3.3 mm diameter) were installed, while in the test sites, larger and conical (root formed, 5 mm diameter) implants were installed. After 4 months of healing, the resorptive patterns of the alveolar crest were evaluated histomorphometrically.
  
  
  RESULTS
  With one exception, all implants were integrated in mineralized bone, mainly composed of mature lamellar bone. The alveolar crest underwent resorption at the control as well as at the test implants. This resorption was more pronounced at the buccal aspects and significantly greater at the test (2.7+/-0.4 mm) than at the control implants (1.5+/-0.6 mm). However, the control implants were associated with residual defects that were deeper at the lingual than at the buccal aspects, while these defects were virtually absent at test implants.
  
  
  CONCLUSIONS
  The installment of root formed wide implants immediately into extraction sockets will not prevent the resorption of the alveolar crest. In contrast, this resorption is more marked both at the buccal and lingual aspects of root formed wide than at standard cylindrical implants.
authors.affiliation: UNESP - Faculty of Dentistry of Araçatuba, São Paulo State University, Sao Paulo, Brazil.
authors.forename: Marco
authors.initials: M
authors.lastname: Caneva
authors.forename: Luiz Antonio
authors.initials: LA
authors.lastname: Salata
authors.forename: Sergio Scombatti
authors.initials: SS
authors.lastname: de Souza
authors.forename: Eriberto
authors.initials: E
authors.lastname: Bressan
authors.forename: Daniele
authors.initials: D
authors.lastname: Botticelli
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
mesh_terms: D016301:Alveolar Bone Loss / Q000145:classification / Q000473:pathology; D000818:Animals; D001641:Bicuspid / Q000601:surgery; D002113:Calcification, Physiologic / Q000502:physiology; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D004285:Dogs; D008334:Mandible / Q000473:pathology / Q000601:surgery; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology*; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D014081:Tooth Extraction; D020390:Tooth Socket / Q000473:pathology / Q000601:surgery*; D014945:Wound Healing / Q000502:physiology
chemical_list: D015921:Dental Implants; D003764:Dental Materials; D014025:Titanium