Five-year prospective follow-up report of the Astra tech standard dental implant in clinical treatment

Between 1994 and 1999, 515 Astra standard implants were placed and document ed prospectively in 107 patients. Of these implants, 364 were placed in ori ginal jawbone, 38 in areas augmented with local osteoplasty, and 113 in bon e grafts from the iliac crest. The main indications for implantation were a n atrophic edentulous alveolar crest (n = 361) and a shortened dental arch (n = 113). Single-tooth implants were excluded. In a special clinical exami nation, 56 patients with 258 implants were investigated. The average in sit u time of the implants was 34.2 months. Failing osseointegration (n = 10), peri-implantitis (n = 10), and implant fracture (n = 1) in 15 patients resu lted in the failure of 21 implants (4.1%). Three patients with 8 implants d ied from malignant tumor. Currently, 27 implants have been lost to follow-u p, and 488 implants remain in situ (95.9%). Under analyses with different i mplant success criteria, the success rate decreased to 85%. Based on the re sults in this patient population, this implant was found to be a useful alt ernative to established implant systems for the indications analyzed.