A feasibility study for removing tissue contamination from porous implants

Porous implants that are unpackaged in the operating room but not implanted are discarded because they must be considered potentially contaminated with tissue. To reduce this waste, a method was developed to decontaminate these implants so that they can be resterilized and implanted. This method consists of ultrasonic scrubbing, sequentially, in aqueous solutions of dishwashing detergent, 7% nitric acid, and 5.25% sodium hypochlorite. The effectiveness of the method was tested by contaminating samples of porous implants with tissue, subjecting them to the decontamination method, and then using the following techniques to determine whether any tissue remained. The weights of samples after decontamination were compared with their weights before contamination. The rate of removal of labeled protein contamination from samples was measured. The capacity of decontaminated samples to activate immune system cells was assayed. Bioburden evaluations were performed on decontaminated samples. Within the measurement capabilities of each technique, no tissue was detected in any sample after decontamination.