Preservation of peri-implant soft and hard tissues using platform switching of implants placed in immediate extraction sockets: a proof-of-concept study with 12- to 36-month follow-up.

摘要

PURPOSE: The purpose of this article is to evaluate the soft- and hard-tissue response to immediately placed implants. In addition, assessment was conducted of the soft tissue response to a transmucosal abutment which was narrower than the implant platform. MATERIALS AND METHODS: This study was conducted to evaluate 10 consecutively placed immediately loaded implants placed in extraction sockets in maxillae without compromised bone tissue. The infection control phase of periodontal therapy was completed in the areas of hopeless teeth prior to extraction. Implants with a 6-mm-platform diameter were placed immediately into the fresh extraction sockets. A provisional 4-mm-diameter transmucosal abutment was subsequently connected, and a provisional crown was adapted and adjusted for nonfunctional immediate positioning. Three months following implant placement, definitive prosthetic rehabilitation was performed. At the time of prosthesis insertion (baseline) and every 6 months thereafter, radiographic assessments, pocket probing depth (PPD), recession, and papilla height were measured. An image analysis software application was used to compare the radiographic bone crestal bone heights at the mesial and distal aspects of the implants. RESULTS: Nine patients with 10 sites were treated. Mean follow-up time was 22 months (range, 18 to 36 months). All 10 implants were found to be clinically osseointegrated. Software analysis of radiographic films showed a bone resorption of 0.78 +/- 0.36 mm. The mean values were significantly lower (P < or = .005) than a mean reference value of 1.7 mm. PPD did not exceed 3 mm in any site (average, 2.8 mm). Rather than recession, there was a mean gain in the buccal margin of 0.2 mm and a mean gain in papilla height of 0.25 mm. CONCLUSION: This proof-of-concept study suggests that immediate loading with platform switching can provide peri-implant hard tissue stability with soft tissue and papilla preservation. (Case Series)