title: A clinical and histologic evaluation of implant integration in the posterior maxilla after sinus floor augmentation with autogenous bone, bovine hydroxyapatite, or a 20:80 mixture.
abstract: OBJECTIVE
  This study was designed to clinically and histologically evaluate the integration of titanium implants in different grafting materials used for maxillary sinus augmentation procedures.
  
  
  METHODS
  A total of 21 patients and 36 maxillary sinuses were augmented with (1) autogenous particulated bone from the mandibular ramus, (2) bovine hydroxyapatite (BH) with membrane coverage, or (3) an 80/20 mixture of BH and autogenous bone. The grafts were allowed to heal for 6 to 9 months prior to placement of microimplants for histology and standard implants for prosthetic rehabilitation. After another 6 months of healing, when abutments were connected, the microimplants were retrieved for histologic and morphometric analyses. The outcome of the standard implants was clinically evaluated after 1 year of loading.
  
  
  RESULTS
  The mean bone-implant contact was 34.6 +/- 9.5%, 54.3 +/- 33.1%, and 31.6 +/- 19.1% for autogenous bone, mixture of 20% autogenous bone/80% BH, and 100% BH, respectively. The corresponding values for the bone area parameter were 37.7 +/- 31.3%, 39.9 +/- 8%, and 41.7 +/- 26.6%. The BH area was found to be 12.3 +/- 8.5% and 11.8 +/- 3.6% for 20% autogenous bone/80% BH and 100% BH, respectively. There were no statistically significant differences for any parameter between any of the groups. After 1 year of loading, 6 of the 33 implants placed in autogenous bone grafts, 2 of the 35 implants placed in the BH/autogenous bone mixture, and 2 of 43 implants placed in BH were lost. There were no statistically significant differences between any of the groups.
  
  
  CONCLUSIONS
  The histomorphometric analysis showed no differences between the 3 groups, indicating that autogenous bone graft can be substituted with bovine hydroxyapatite to 80% or 100% when used for maxillary sinus floor augmentation. The effect of adding autogenous bone remains unclear but may allow for a reduction of the healing time.
  
  
  CONCLUSIONS
  The results from this clinical and histologic study indicate that similar short-term results can be expected when using autogenous bone, BH, or a mixture of them for maxillary sinus floor augmentation and delayed placement of dental implants.
authors.affiliation: Clinic for Oral & Maxillofacial Surgery, Public Health Service, Gävle City, Sweden. mats.hallman@lg.se
authors.forename: Mats
authors.initials: M
authors.lastname: Hallman
authors.forename: Lars
authors.initials: L
authors.lastname: Sennerby
authors.forename: Stefan
authors.initials: S
authors.lastname: Lundgren
mesh_terms: D020341:Absorbable Implants; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use*; D018786:Bone Substitutes / Q000627:therapeutic use*; D016025:Bone Transplantation / Q000379:methods / Q000473:pathology; D002417:Cattle; D000044:Dental Abutments; D015921:Dental Implants; D017886:Durapatite / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008437:Maxilla / Q000473:pathology / Q000601:surgery*; D008443:Maxillary Sinus / Q000473:pathology / Q000601:surgery; D008567:Membranes, Artificial; D008875:Middle Aged; D016348:Osseointegration; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D014025:Titanium; D014182:Transplantation, Autologous; D016896:Treatment Outcome; D014945:Wound Healing
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D015921:Dental Implants; D008567:Membranes, Artificial; D017886:Durapatite; D014025:Titanium