title: Immediate loading of fixed provisional prostheses using four implants for the rehabilitation of the edentulous arch: a prospective clinical study.
abstract: OBJECTIVE
  The purpose of this prospective clinical trial was to evaluate over a 5-year period the treatment outcomes for immediately loaded full-arch fixed prostheses supported by two axially inclined and two tilted implants used to rehabilitate edentulous arches. This report presents preliminary 1-year results.
  
  
  METHODS
  Thirty-seven patients were recruited for treatment with either mandibular or maxillary full-arch fixed prostheses supported by four implants. Within 24 hours, the implants were immediately loaded with screw-retained full-arch acrylic resin provisional restorations. Definitive reconstructions were delivered 6 months later. Complete full-arch prostheses were supported by metal frameworks combined with high-density acrylic resin. Follow-up visits were scheduled for 6 and 12 months after initial prosthetic loading and then annually for up to 5 years. Digital radiographs were obtained immediately, 6 months after surgery, and at each annual follow-up visit. Marginal peri-implant bone levels were assessed using digital image analysis.
  
  
  RESULTS
  The 1-year implant survival rates were 96.0% for axially positioned implants and 94.6% for tilted implants. The survival rates were 96.6% for maxillary implants and 98.7% for mandibular implants. The prosthetic survival rate was 100%. No significant differences were found in the results for tilted versus axially positioned implants. One year after loading, the mean marginal bone loss was 0.82 ± 0.31 mm around the axially oriented implants and 0.76 ± 0.49 mm around the tilted implants (P ⋜ .05).
  
  
  CONCLUSIONS
  Preliminary data from this clinical trial show high implant survival rates for immediately loaded full-arch prostheses supported by four implants. Immediate loading of tilted implants may be considered a viable treatment option for the rehabilitation of edentulous patients.
authors.affiliation: Private Institute of Periodontology and Implantology, Rosenkavalierplatz 18, Munich, Germany. marc.hinze@ipi-muc.de
authors.forename: Marc
authors.initials: M
authors.lastname: Hinze
authors.forename: Tobias
authors.initials: T
authors.lastname: Thalmair
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Bolz
authors.forename: Hannes
authors.initials: H
authors.lastname: Wachtel
mesh_terms: D003758:Dental Implantation, Endosseous / Q000379:methods*; D003794:Dental Restoration, Temporary; D006801:Humans; D057893:Immediate Dental Implant Loading; D011446:Prospective Studies