title: Primary stability determination of implants inserted in sinus augmented sites: 1-step versus 2-step procedure.
abstract: OBJECTIVE
  The aim of this study was to evaluate the primary stability of implants placed immediately after a sinus lift, compared with implants placed in the area treated with a sinus lift 6 months before.
  
  
  METHODS
  Patients with a residual bone height of at least 4 mm were treated with a 1-stage procedure (group A) and patients with a residual bone height < 4 mm with a 2-stage approach (group B). Sinus lift was always performed with 50% autogenous bone and 50% deproteinized bovine bone mineral. Data recorded included maximum insertion torque (IT), resonance frequency analysis (RFA) values, and bone density, length, and diameter. It was recorded whether an implant was removed within 6 months after insertion.
  
  
  RESULTS
  Fourteen patients were included in group A and 16 patients in group B; 96 implants were inserted. Mean IT was 23.77 ± 12.63 N·cm in group A and 26.48 ± 20.80 N·cm in group B. Mean RFA was 65.25 ± 4.45 implant stability quotient (ISQ) in group A and 67.92 ± 10.99 ISQ in group B. No statistically significant differences were found. All implants were osseointegrated.
  
  
  CONCLUSIONS
  The results show that the implants studied can obtain a sufficient primary stability in both clinical situations without statistically significant differences.
authors.affiliation: *Private Practice, Bologna, Italy. †Private Practice, Bologna, Italy. ‡Full Professor, Department of Medical, Oral, and Biotechnological Sciences, University of Chieti-Pescara, Chieti, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Degidi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Daprile
authors.forename: Adriano
authors.initials: A
authors.lastname: Piattelli
mesh_terms: D000328:Adult; D000368:Aged; D003758:Dental Implantation, Endosseous / Q000379:methods*; D017268:Dental Prosthesis Retention; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D059546:Sinus Floor Augmentation / Q000379:methods*; D016896:Treatment Outcome