Summary of an expert discussion by EADT eV in collaboration with the FZT
At an expert discussion in October 2016, EADT eV, together with invited specialists, addressed an explosive topic from everyday implant prosthetics: “The dental preparation and cleaning of implant abutments”. Based on the current study situation and scientific study results, a statement was drawn up that addresses the post-processing and cleaning of individual implant prosthetic components.
Based on the expert discussion, EADT eV created a complex summary that reflects the current status quo. In the paper, eight dental technology questions are answered in detail and thus raise awareness of how to deal with this topic. Ultimately, however, the working group found that the current scientific data does not yet provide sufficient information for a validated dental preparation and cleaning process for implant abutments.
Introduction
While metallic implant structures (e.g. titanium or titanium alloys), purely theoretically, could be sterilized in an autoclave (DIN EN ISO 14937), the sterilization of ceramic abutments in moist heat could potentially damage their crystal structure (degradation) [6] and thus possibly lead to a premature fracture of the restoration. There are currently no protocols from zirconium oxide manufacturers for sterilization in autoclaves. The demand for a sensible, valid processing and cleaning process is becoming louder and louder. Based on the following three theses, eight dental technology questions were discussed.
Thesis 1: Validated recommendation for action
Since clear specifications based on scientific research and clinical studies have been established for the endosseous area of implants in recent decades, such validated parameters for implant prosthetic abutments are missing. Most of the items currently used in everyday life are individual abutments that were manufactured by a specialized manufacturing center or a dental laboratory. There is a need for clear guidelines for manufacturing and post-processing, which should also be applied when using prefabricated implant abutments.
Thesis 2: Hygiene protocol
While metallic implant structures (e.g. titanium or titanium alloys) could theoretically be sterilized in an autoclave (DIN EN ISO 14937), the sterilization of ceramic abutments in moist heat could possibly damage their crystal structure (degradation) [6] and thus may lead to premature fracture of the restoration. There are currently no protocols from the zirconium oxide manufacturers for sterilization in autoclaves. The demand for a sensible, valid processing and cleaning process is becoming louder and louder.
Thesis 3: Surface topography
In addition to cleanliness, great attention must be paid to the surface topography in the submucosal area of the implant abutment. The roughness and surface tension are crucial here. Both factors are crucial and do not always correlate with each other. It can be assumed that there is a threshold value for roughness at which the accumulation of bacteria and plaque is low and at the same time the attachment of fibroblasts and the adaptation of the peri-implant mucosa are optimally supported [7]. A surface that is too rough and has a high surface tension can pose the risk of increased plaque accumulation. If the surface is too “smooth” with little roughness and low surface tension, the fibroblasts of the peri-implant mucosa cannot “grow” optimally. Studies have shown that surface roughness varies greatly in both industrial and laboratory production [8, 33].