The cleaning procedures for implant abutments are a controversial topic. Sterilize? Disinfect? or??? …. Dentists and dental technicians are looking for well-founded answers.
In an expert discussion at EADT eV, a working group discussed eight questions. Based on the current study situation and scientific research results, possible procedures for the post-processing and cleaning of individual implant prosthetic components have been examined in more detail. The aim was to provide dental technicians with a practical and reproducible workflow for achieving a cleaned abutment that is recognized according to general guidelines. The discussion resulted in a complex summary [EADT eV paper “Dental preparation and cleaning processes for implant abutments”]. This makes the dental technician aware of how to deal with this problem.
Excerpt from the EADT paper “Dental preparation and cleaning processes for implant abutments”:
Which cleaning processes are known?
Chemical cleaning
Chemical cleaning is carried out by using various alcohols or disinfectants. Cleaning according to the protocol with acetone-isopropanol-ethanol-distilled water in an ultrasonic bath can chemically change the surface properties of materials [1, 4].
Sterilization autoclave
In autoclaves, a temperature increase occurs due to the applied steam heat [4]. The autoclave chamber must remain closed until the heat drops to room temperature and all moisture has dried. Therefore, an autoclave is not recommended for heat-sensitive biomaterials [3, 4, 5].
Gamma irradiation
Gamma irradiation is used to sterilize biomaterials and medical devices. The ionized high energy is powerful enough to promote DNA damage without leaving toxic residue. Because of its good penetration depth, gamma irradiation is useful for densely packed products and packaged materials.
Ultraviolet light
UV light is also used as a surface sterilization method. To eliminate bacteria, the shortest wavelength range with the highest energy intensity (280-100 nm) is suitable because ionized high energy is strong enough to promote DNA damage without releasing toxic residues [4].
Ethylene oxide
Ethylene oxide is a sterilization process used for cellulose-based biomaterials and plastic products. However, it leaves toxic residues on the surface, which could have a negative impact on cell growth on the material surface [4, 2].
Plasma
Plasma pretreatment is a novel cleaning method for which there are promising pilot studies to date, but there are no sufficiently validated statements. In general, plasma cleaning is defined as a process that uses partially or fully ionized gas with approximately equal numbers of positively and negatively charged particles.
What an adequate hygiene chain could look like based on today's findings is shown, among other things, in the summary of the expert discussion.
- [1] Gehrke P, Tabellion A, Fischer C. Microscopical and chemical surface characterization of CAD/CAM zircona abutments after different cleaning procedures. A qualitative analysis. J Adv Prosthodont 2015; 7:151-159
- [2] Holyoak GR, Wang S, Liu Y. Toxic effects of ethylene oxide residues on in vitro production of bovine embryos. Theriogenology 1995; 43:237
- [3] Lausmaa J, Kasemo B, Hansson S. Accelerated oxide growth on titanium implants during autoclaving caused by fluorine contamination. Biomater 1985; 6:23–27
- [4] Park JH, Olivares-Navarrete R, Baier RE, Meyer AE, Tannenbaum R, Boyan BD, Schartz Z. Effect of cleaning and sterilization on titanium implant surface properties and cellular response. Acta Biomater 2012; 8: 1966-1975 [5] Premnath V, Harris WH, Jasty M, Merrill EW. Gamma sterilization of UHMWPE articular implants: an analysis of the oxidation problem. Biomater 1996; 17: 1741–175