Osteoblasts Response to Date-Expired Implants renewed by H₂O₂ Gas Plasma

Dental implants, otherwise uncompromised, are occasionally found to be date-expired within intact or opened packages, denying their clinical use unless they can be reliably re-sterilized and made equivalent in reaction to new implants within receiving bone sites. This investigation identified an FDA-approved low-temperature gas plasma sterilization approach –in residual hydrogen peroxide (H₂O₂) vapor at low pressure, restoring even grossly contaminated dental implants to sterility within an hour and renewing their surface qualities to those of as-manufactured implants with regard to their support for attachment and growth of human alveolar osteoblasts.

Method:

Studies were conducted on actual date-expired dental implants of three different types, as packaged as well as after deliberate contamination with Candida albicans or adventitious atmospheric organisms, through microbiological broth-based and agar-based assays to prove sterility and through tissue culture assays with human alveolar osteoblasts to prove renewed cellular attachment and growth characteristics. The cells’ activity was assessed by cell’s activity test MTT assay. Furthermore, cells’ attachment profile were examined by Scanning Electron Microscopy (SEM) and differential interference contrast (DIC) light microscopy

Result:

Osteoblasts’ growth and viability were confirmed by statistically equivalent outcomes for as-manufactured implants and clean/re-sterilized (by H2O2 gas plasma) implants, judged by cellular mitochondrial activity assays (MTT), differential interference contrast (DIC) light microscopy, and SEM. In this study, ANOVA followed by HSD Tukey test was used to statistically analyze the collected data.

Conclusion:

The results demonstrated that date-expired dental implants could be safely and effectively restored to conditions generally associated with the good clinical performance of osseointegated cpTi devices.