Enzymatic cleaners fail to decontaminate and establish sterile surface in used healing abutments: Study

A study was done to evaluate four decontamination strategies utilizing enzymatic agents available in most clinical settings to determine (1) the amount of biomaterial that can be removed in a group of previously used healing abutments (uHAs) and (2) the degree to which the decontaminated healing abutments are capable of inducing an inflammatory response in vitro compared to new healing abutments. In total, 50 healing abutments were collected following 2 to 4 weeks of intraoral use and distributed randomly into five test groups (groups A–E; n = 10 per group). Group A used enzymatic cleaner foam and an autoclave. Group B used an ultrasonic bath with enzymatic cleaner and an autoclave. Group C used a prophy jet, enzymatic cleaner foam, and an autoclave. Group D used a prophy jet, an ultrasonic bath with an enzymatic cleaner, and an autoclave. Lastly, group E used a prophy jet and an autoclave.

The control group consisted of 10 new and sterile HAs. Residual protein concentration was determined by a Micro BCA protein assay (Thermo Fisher Scientific) while healing abutments from each group were stained with Phloxine B and macroscopically examined for the presence of debris. Human primary macrophages were exposed to healing abutments to examine the inflammatory potential, and supernatant levels of nine cytokine and chemokine profiles were analyzed using a multiplex bead assay.

Results: All test groups showed differences in the degree of visual decontamination compared to controls. Groups D and E displayed the most effective surface debris removal and reduced protein concentration, while group A was the least effective. However, compared to controls, all test groups showed high levels of inflammatory cytokine secretion via multiplex assay for up to 5 days. The study found that decontaminating used healing abutments utilizing enzymatic cleaners failed to reestablish inert healing abutment surfaces and prevent an inflammatory immune response in vitro. Clinicians should not reuse healing abutments even after attempts to decontaminate and sterilize healing abutments surfaces.

Reference:

Abreu OJ, Estepa AV, Naqvi AR, Nares S, Narvekar A. Assessment of Detoxification Strategies for Used Dental Implant Healing Abutments: Macroscopic and Biologic Implications. Int J Oral Maxillofac Implants. 2024 Aug 29;39(4):516-525. doi: 10.11607/jomi.10651. PMID: 37910839.