title: A three-year follow-up report of a comparative study of ITI Dental Implants and Brånemark System implants in the treatment of the partially edentulous maxilla.
abstract: BACKGROUND
  Many longitudinal studies of different implant systems have been published but few controlled randomized investigations have been reported. A 1-year report of a comparative study of ITI Dental Implant System implants (Straumann AG, Waldenburg, Switzerland) and Brånemark System implants (Nobel Biocare AB, Gothenburg, Sweden) has been published by the present authors. This paper is a 3-year follow-up of that randomized study.
  
  
  OBJECTIVE
  The aim of the study was to compare the outcome of fixed partial prostheses supported by ITI or Brånemark implants. The outcome was evaluated primarily in terms of survival rates and changes in marginal bone level.
  
  
  METHODS
  The study group comprised 28 patients with anterior residual dentition in the maxilla. The patients were provided with two to four implants on each side of the dentition and were randomly allocated to Brånemark implants or ITI implants; 77 ITI implants and 73 Brånemark implants were inserted. After 6 months abutment connections were made to both ITI and Brånemark implants. All patients were provided with fixed partial prostheses of gold-ceramic. The patients were followed up annually with clinical and radiographic examinations for 3 years
  
  
  RESULTS
  Two Brånemark implants and two ITI implants were lost. The Brånemark implants were lost before loading whereas the ITI implants were lost because of periimplantitis. The survival rate for both groups was 97.3%. The mean marginal bone level of the Brånemark implants was situated 1.8 mm from the reference point at both the baseline and the 3-year examinations. The corresponding values for the ITI implants were 1.4 mm at baseline and 1.3 mm after 3 years. There was no significant difference between the implant systems with regard to bone level or bone level change. A steady state of the marginal bone level was calculated to have been reached after 3 years for 95.5% of the Brånemark implants and 87.1% of the ITI implants. Periimplantitis (infection including pus and bone loss) was observed with seven ITI implants but with none of the Brånemark implants. This difference was statistically significant.
  
  
  CONCLUSIONS
  No statistically significant differences were found between the implants studied, except for the frequency of periimplantitis, which was higher for the ITI implants. The survival rates were high, and the marginal bone loss was small for both systems.
authors.affiliation: Department of Oral and Maxillofacial Surgery, University Hospital, Linköping, Sweden.
authors.forename: Per
authors.initials: P
authors.lastname: Astrand
authors.forename: Bo
authors.initials: B
authors.lastname: Engquist
authors.forename: Bengt
authors.initials: B
authors.lastname: Anzén
authors.forename: Tom
authors.initials: T
authors.lastname: Bergendal
authors.forename: Mats
authors.initials: M
authors.lastname: Hallman
authors.forename: Ulf
authors.initials: U
authors.lastname: Karlsson
authors.forename: Sven
authors.initials: S
authors.lastname: Kvint
authors.forename: Leif
authors.initials: L
authors.lastname: Lysell
authors.forename: Torgil
authors.initials: T
authors.lastname: Rundcranz
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants / Q000009:adverse effects; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D019094:Dental Prosthesis, Implant-Supported; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003830:Denture, Partial, Fixed; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000000981:diagnostic imaging / Q000534:rehabilitation*; D008297:Male; D008437:Maxilla / Q000601:surgery; D008875:Middle Aged; D010518:Periodontitis / Q000209:etiology*; D011859:Radiography
chemical_list: D015921:Dental Implants