title: Osteotome sinus floor elevation with and without grafting: an animal study in Labrador dogs.
abstract: OBJECTIVE
  To evaluate implant stability and histological outcomes after osteotome sinus floor elevation (OSFE) procedure, and to compare new bone formation and implant osseointegration with and without grafting.
  
  
  METHODS
  OSFE with simultaneous implant placement was conducted bilaterally on 6 Labrador dogs. Twenty-four implants were placed. The right side sinus (Group 1) was grafted with biphasic calcium phosphate (BCP), whereas the left side (Group 2) was left without any grafting materials. The animals were euthanized 8 and 24 weeks after surgery for histological and histomorphometric assessment. Bone-to-implant contact (BIC%), alveolar bone height (ABH), bone density (BD) and grafting material density (GMD) were measured. The implant stability (ISQ) was assessed using resonance frequency analysis (RFA) at implant placement and 1, 2, 4, 8, 12, 24 weeks after surgery.
  
  
  RESULTS
  Endo-sinus new bone with direct contact to implant surface were observed in two groups at both time points. ABH showed no difference between groups at both time points. BIC% and BD in Group 2 (40.05%, 35.90%) was higher than those in Group 1 (23.30%,25.59%) at 24 weeks. Significant shrinkage of grafting material was seen in Group 1. The GMD in Group 1 at 8 weeks was 24.35%, while it dropped to 19.90% at 24 weeks. The changing pattern of ISQ for both groups were similar.
  
  
  CONCLUSIONS
  Spontaneous new bone formation and better bone-to-implant contact were found for OSFE without grafting. The grafting material application during OSFE procedure showed no advantages in histological results.
authors.affiliation: Department of Oral and Maxilliofacial Implantology, Shanghai Ninth People's Hospital, School of Medicine, Shanghai Institute of Stomatology, Shanghai Jiaotong University, Shanghai, China.
authors.forename: Mi-Si
authors.initials: MS
authors.lastname: Si
authors.forename: Jia-Ji
authors.initials: JJ
authors.lastname: Mo
authors.forename: Long-Fei
authors.initials: LF
authors.lastname: Zhuang
authors.forename: Ying-Xin
authors.initials: YX
authors.lastname: Gu
authors.forename: Shi-Chong
authors.initials: SC
authors.lastname: Qiao
authors.forename: Hong-Chang
authors.initials: HC
authors.lastname: Lai
mesh_terms: D016301:Alveolar Bone Loss / Q000601:surgery; D000818:Animals; D018786:Bone Substitutes / Q000627:therapeutic use; D016025:Bone Transplantation / Q000379:methods; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D004285:Dogs; D006882:Hydroxyapatites / Q000627:therapeutic use; D007576:Jaw, Edentulous, Partially / Q000601:surgery; D008297:Male; D008437:Maxilla / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D063166:Maxillary Osteotomy; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D016348:Osseointegration; D010012:Osteogenesis; D059546:Sinus Floor Augmentation / Q000379:methods*
chemical_list: D018786:Bone Substitutes; D015921:Dental Implants; D006882:Hydroxyapatites; C074950:hydroxyapatite-beta tricalcium phosphate
keywords: animal study; bone formation; implant dentistry; implant stability; osteotome sinus floor elevation; sinus grafting