Immediate provisionalization of Astra Tech implants in healed and extraction sites: 1 to 11-year results

LD8FN ePOSTER CLINICAL RESEARCH – SURGERY

Background: Since the concept of immediate provisionalization has been introduced, it remained an open issue, whether this procedure increases the risk of implant loss, marginal bone resorption or increased probing depths in long-term observation.

Aim/Hypothesis: Therefore, this retrospective study examines the 1 to 11-year hard and soft tissue changes at immediate provisionalized implants placed in healed and extraction sites.

Materials and Methods: Between 2007 and 2016 711 microthreaded implants were placed in 271 patients into healed and extraction sites. All implants were immediately provisionalized. The primary outcome parameter was implant survival. Interproximal marginal bone level, periimplant probing depths, and the implant success were considered as secondary outcome parameters.

Results: Seventy-four patients with 177 implants did not meet the inclusion criteria or did not attend follow-up examinations (drop-outs). Four implants were lost. 530 implants in 197 patients were followed for a mean period of 50.6 months (implant success 99.0 percent). Marginal bone height averaged -0.14 mm apical to the implant shoulder, for smoker -0.41 mm vs. NO-smokers -0.10 mm, and for healed -0.23 mm vs. extraction sites -0.10 mm. Implant success, defined as implant survival, marginal bone loss less than 1 mm and probing depths no more than 5 mm, was 49.9 percent for smoker and 72.1 percent for NO-smokers and 80.6 percent for mandibular and 73.1 percent for maxillary implants. No differences in success were found for healed vs. extraction sites, anterior vs. posterior implants, and for the history of periodontitis.

Conclusions and Clinical Implications: Clinical and radiographic results provide evidence that the immediate provisionalization of implants placed the healed or extraction sites is a predictable treatment concept in longer term observation. Smoking increases the risk for marginal bone loss and long-term failure.

Keywords: immediate provisionalization, immediate implant placement, delayed implant placement