title: Performance of double acid-etched surface external hex titanium implants in relation to one- and two-stage surgical procedures.
abstract: BACKGROUND
  The use of external hex titanium implants is widely accepted; however, in the past few years, they have been placed by using not only the traditional two-stage surgical protocol, but also the one-stage surgical protocol. The aim of the present study was to compare the success rates that can be obtained from two-stage surgeries (conventional protocol) and one-stage surgeries when double acid-etched surface external hex titanium implants are used.
  
  
  METHODS
  A total of 654 double acid-etched surface external hex titanium implants were studied in 195 patients (109 females and 86 males) aged 18 to 79 (mean 49.20). These patients were followed-up both clinically and radiographically for 3 years. Among these implants, 338 were inserted by means of two-stage surgery and 316 were placed following the one-stage surgery protocol.
  
  
  RESULTS
  The success rate of the whole sample of double acid-etched surface implants was 99.23%. The results showed a 99.05% success rate for one-stage surgeries and 99.40% rate for two-stage surgeries. Only three of the implants inserted by performing one-stage surgery and two of the implants placed using two-stage surgery failed before they were loaded. No implants were lost after the loading was completed. The bone level at 12 months was 0.58 mm for one-stage-placed implants and 0.54 mm for two-stage-placed implants. At 24 months the bone level was 0.77 mm and 0.68, respectively, and at 36 months 0.89 and 0.83.
  
  
  CONCLUSIONS
  The similar and high success rates obtained in one- and two-stage surgeries using double acid-etched surface external hex titanium implants demonstrate that it is possible to choose the most convenient surgical procedure for each particular case without increasing the risk of failure.
authors.affiliation: ibanezjc@onenet.com.ar
authors.forename: Juan C
authors.initials: JC
authors.lastname: Ibañez
authors.forename: Marcelo J
authors.initials: MJ
authors.lastname: Tahhan
authors.forename: Juan A
authors.initials: JA
authors.lastname: Zamar
mesh_terms: D000134:Acid Etching, Dental; D000293:Adolescent; D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000145:classification; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D005260:Female; D005500:Follow-Up Studies; D016557:Guided Tissue Regeneration, Periodontal; D006801:Humans; D008297:Male; D008875:Middle Aged; D016348:Osseointegration; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D016896:Treatment Outcome
chemical_list: D015921:Dental Implants; D014025:Titanium