One-Year Outcomes of Subcrestal Platform-Switched Implants With and Without Sterile Prosthetic Abutments: A Randomized Controlled Trial.

ABSTRACT

Surface contaminants on customized implant abutments could trigger inflammatory response in the peri-implant tissues. The aim of this randomized controlled study was to assess the radiographic bone changes around implants restored with customized, platform-switched abutments, with and without autoclave treatment, 12 months after definitive restoration. Dental implants were placed 1 mm subcrestally in 64 systemically healthy patients (mean age 63.3 ± 10.0 years, 31 with history of periodontitis) to replace single or multiple missing teeth. According to a randomization list, abutments were subjected to steam and autoclave sterilization (43 implants, test group) or steam cleaning alone (44 implants, control group). Periapical standardized radiographs were taken at the time of implant insertion, prosthetic abutment connection and 12 months after definitive cement-retained restoration. All implants were clinically stable without any sign of infection at the 12-month follow-up. An average marginal bone loss of 0.25 ± 0.19 mm was found in the test group compared to 0.35 ± 0.23 mm in the control group without statistically significant difference, while the percentage of bleeding sites was significantly higher in the control group (8.7 ± 13.1% versus 19.1 ± 19.8%, P = .035). Autoclave treatment of customized abutments would seem to reduce the inflammatory response around subcrestally placed implants.