title: A prospective, multicenter, randomized-controlled 5-year study of hybrid and fully etched implants for the incidence of peri-implantitis.
abstract: BACKGROUND
  The dual acid-etched (DAE) implant was commercially introduced in 1996 with a hybrid design incorporating a machined surface in the coronal region from approximately the third thread to the seating surface. This design was intended to reduce the risks of peri-implantitis and other related soft tissue complications that were reported for implants with surface roughness in the coronal region. The objective of this prospective, randomized-controlled clinical trial was to determine the incidence of peri-implantitis for a fully etched implant with the DAE surface extending to the implant platform.
  
  
  METHODS
  Patients had implant sites randomly assigned to receive one hybrid control implant and at least one fully etched test implant in support of a short-span fixed restoration to ensure that variables (e.g., demographics, jaw locations, and bone density) were consistent between groups. Prostheses were inserted 2 months after implant placement with follow-up evaluations scheduled annually for 5 years to assess mucosal health based on bleeding on probing, suppuration, and probing depths. Evaluations also included radiographic and mobility assessments.
  
  
  RESULTS
  One hundred twelve patients who were enrolled at seven centers received 139 control and 165 test implants (total: 304 implants). With >5 years of postloading evaluations, there was one declaration of peri-implantitis associated with a control implant that was successfully treated later. Clinical probing and radiographic assessments did not reveal differences between groups in mucosal health outcomes or other signs of peri-implantitis.
  
  
  CONCLUSIONS
  Five-year results of this randomized-controlled study showed no increased risk of peri-implantitis for fully etched implants compared to hybrid-designed implants.
authors.affiliation: Private practice, Gefle, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Zetterqvist
authors.forename: Sylvan
authors.initials: S
authors.lastname: Feldman
authors.forename: Bruce
authors.initials: B
authors.lastname: Rotter
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Vincenzi
authors.forename: Jan L
authors.initials: JL
authors.lastname: Wennström
authors.forename: Andrea
authors.initials: A
authors.lastname: Chierico
authors.forename: Renée M
authors.initials: RM
authors.lastname: Stach
authors.forename: James N
authors.initials: JN
authors.lastname: Kenealy
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D016009:Chi-Square Distribution; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000379:methods; D015921:Dental Implants / Q000009:adverse effects*; D003775:Dental Polishing; D019094:Dental Prosthesis, Implant-Supported / Q000009:adverse effects; D019232:Dental Restoration Failure; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010518:Periodontitis / Q000209:etiology*; D011446:Prospective Studies; D016459:Prosthesis-Related Infections / Q000209:etiology*; D011859:Radiography; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D055815:Young Adult
chemical_list: D015921:Dental Implants