title: Long-term outcomes of osteotome sinus floor elevation without bone grafts: a clinical retrospective study of 4-9 years.
abstract: OBJECTIVE
  To evaluate the long-term clinical and radiographic outcomes of dental implant placed using osteotome sinus floor elevation (OSFE) without bone grafts, and to analyze the potential influence factors of implant survival and endo-sinus bone remodeling.
  
  
  METHODS
  A retrospective study design was adopted. The clinical and radiographic data of 96 implants in 80 patients were collected after 4-9 (mean 5.40) years follow-up. Implant failures, peri-implant marginal bone loss (MBL), and endo-sinus bone remodeling on the radiographs were evaluated. A life-table analysis was used to assess the implant survival. Statistical models were established to investigate the potential influence factors of implant survival and endo-sinus bone gain (ESBG).
  
  
  RESULTS
  In total, nine implants in seven patients failed, giving the 9-year cumulative survival rates of 90.6% and 91.3% for implant-based analysis and patient-based analysis, respectively. The mean MBL between implant installation and the 4- and 9-year follow-up visit was 0.46 ± 0.88 and 0.50 ± 1.69 mm, respectively. The average ESBG on radiographs was 2.95 ± 1.25 and 2.16 ± 1.13 mm at the 4- and 9-year follow-up. The final ESBG was found to be positively correlated to implant protrusion length after surgery without any other factors related. The implant survival rate was significantly lower in severe atrophic site (residual bone height <5 mm).
  
  
  CONCLUSIONS
  Osteotome sinus floor elevation without bone grafts is a predictable treatment modality in the long run. But it should be used with caution when the initial bone height of the edentulous site is lower than 5 mm. The final endo-sinus bone height was found to be positively correlated to implant protrusion length measured on radiographs immediately after implant installation.
authors.affiliation: Department of Oral Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Mi-Si
authors.initials: MS
authors.lastname: Si
authors.affiliation: Department of Oral Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yi-Wen
authors.initials: YW
authors.lastname: Shou
authors.affiliation: Dental Clinic, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Yi-Tian
authors.initials: YT
authors.lastname: Shi
authors.affiliation: Department of Oral Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Guo-Li
authors.initials: GL
authors.lastname: Yang
authors.affiliation: Department of Oral Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
authors.forename: Hui-Ming
authors.initials: HM
authors.lastname: Wang
authors.affiliation: Department of Oral Implantology, Stomatology Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China. hfm@zju.edu.cn.
authors.forename: Fu-Ming
authors.initials: FM
authors.lastname: He
mesh_terms: D000328:Adult; D000368:Aged; D016723:Bone Remodeling; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010027:Osteotomy; D012189:Retrospective Studies; D059546:Sinus Floor Augmentation / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D015921:Dental Implants
keywords: bone remodeling; dental implant; osteotome sinus floor elevation; radiographic analysis