Osseointegration of rough acid-etched titanium implants: 5-year follow-up of 100 minimatic implants

During 1992, 100 Minimatic screw implants made of titanium alloy (titanium- aluminum-vanadium) with a machined rough acid-etched surface were placed in 63 consecutive partially edentulous patients. At second-stage surgery, whi ch was performed after a 4- to 6-month healing period, none of the implants showed signs of mobility, peri-implant infection, or bone loss from the cr est of the ridge. Each patient was restored with a fixed prosthesis and ree xamined every 3 months during the first year. Periapical radiographs were t aken annually up to 5 years. These revealed no signs of peri-implant radiol ucencies involving any of the implants, and mean alveolar bone loss was les s than 1 mm at the 5-year examination. One implant was considered a late fa ilure because of a peri-implant infection that developed during the first y ear, although the implant was still functional at year 5. Another patient w ith 2 implants dropped out during the fifth year of the study, although bot h implants had been considered successful up to that point. Based on annual measurements of Plaque Index, Sulcular Bleeding Index, pocket probing dept h, attachment level, width of keratinized mucosa, and hand-tested mobility, 97 of the remaining 98 implants were considered successful, resulting in a 98% success rate. This 5-year study confirms that Minimatic machined acid- etched implants provide predictable osseointegration results and supports t he conclusion of other reports that titanium implants with a rough surface can fulfill the requirements of Albrektsson et al (1986) for implant succes s.