title: The NobelGuide®All-on-4®Treatment Concept for Rehabilitation of Edentulous Jaws: A Retrospective Report on the 7-Years Clinical and 5-Years Radiographic Outcomes.
abstract: BACKGROUND
  There is a necessity of studies documenting the long-term outcome of full-arch flapless rehabilitations.
  
  
  OBJECTIVE
  To evaluate the 7 years implant and prosthesis survival rate and 5-years marginal bone loss of full-arch fixed prosthetic rehabilitations supported by implants in immediate function with the All-on-4®treatment concept using a computer guided surgical protocol (NobelGuide®, Nobel Biocare).
  
  
  METHODS
  This retrospective clinical study included 111 edentulous patients (n = 53 bruxers; n = 21 smokers; n = 59 systemically compromised), rehabilitated between February 2005 and November 2010 with 532 implants with the All-on-4®treatment concept using NobelGuide®. Outcome measures were implant and prosthesis survival, marginal bone loss at 5-years and the incidence of mechanical and biological complications. Survival was calculated using life-table analysis. Inferential analysis was performed to compare the difference in marginal bone loss between axial and tilted implants.
  
  
  RESULTS
  Sixteen patients were lost to follow-up. The implant cumulative survival rate was 94.5% at 7 years. Prosthetic survival was 97.8% (n = 3 prosthetic failures). The average (standard deviation) marginal bone loss at 5 years was 1.3 mm (1.06 mm) overall, 1.27 mm (1.02 mm) for tilted implants and 1.34 mm (1.1 mm) for axial implants (p < .001). Ninety-one patients experienced complications in the provisional prostheses (n = 47 patients who were bruxers; n = 25 patients with implant-supported rehabilitation as opposing dentition) ranging from prosthetic fracture (n = 66 patients) to abutment or prosthetic screw loosening (n = 74 patients). Thirty-three patients experienced complications in the definitive prostheses (all exclusive to patients who were bruxers or had implant-supported rehabilitations as opposing dentition) ranging from acrylic-resin prosthetic/crown fracture (n = 23 patients) to abutment or prosthetic screw loosening (n = 10 patients). Twenty-five patients (22%) registered peri-implant pathology.
  
  
  CONCLUSIONS
  Within the limitations of this study, it is possible to conclude that this treatment modality for completely edentulous jaws is possible with high long-term survival outcomes. Bruxing and smoking habits had a negative impact on implant failure, mechanical, and biological complications.
authors.affiliation: Department of Oral Surgery, Maló Clinic, Private practice, Lisbon, Portugal.
authors.forename: Armando
authors.initials: A
authors.lastname: Lopes
authors.affiliation: Department of Oral Surgery, Maló Clinic, Private practice, Lisbon, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Maló
authors.affiliation: Private practice, Research and Development, Maló Clinic, Lisbon, Portugal.
authors.forename: Miguel
authors.initials: M
authors.lastname: de Araújo Nobre
authors.affiliation: Oral Surgery and Implant Dentistry Department, School of Dentistry, University of Granada, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Sánchez-Fernández
authors.affiliation: Department of Oral Surgery, Maló Clinic, Private practice, Lisbon, Portugal.
authors.forename: Inês
authors.initials: I
authors.lastname: Gravito
mesh_terms: D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D003758:Dental Implantation, Endosseous / Q000379:methods; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging / Q000534:rehabilitation* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011861:Radiography, Dental; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted; D016019:Survival Analysis
keywords: clinical research; computer assisted; edentulous mandible; edentulous maxilla; flapless implant surgery; immediate function