Metal-free implants are made from zirconia which is a bio-compatible, ceramic material. Zirconia completely assimilates (osseointegrates) into jaw bone without any signs of inflammation or foreign body rejection.
In some patients, zirconia implants can elicit fewer allergic reactions than metal implants. If a titanium sensitivity occurs, it may be years after the implant is placed. Symptons may include itchiness and inflammation around implant sites that can contribute to bone loss and the potential implant failure.
MELISA testing is diagnostic tool used to identify metal allergies.
Titanium implants are gray in color. In patients with thin or receding gum tissue can show the gray implant collar. Zirconia is white and therefore will not show thru thin tissue.
Zirconia is inert and resistant to chemical corrosion. An article studying crevice corrosion testing of titanium implants in function. It found corrosion around implants to be “insidious and very rapid, and may leach several ions into the crevicular space activating the host complement response and causing an adverse reaction that may or may not be tolerated”.
Corrosion may be more prevalent if dissimilar metal restorations are present such as amalgam fillings, alloy metal crowns, bridges or gold onlays / inlays and may be more active in the presence of fluoride present in some water supplies, toothpastes and mouthwashes. Titanium has been shown to migrate from the implant site into surrounding tissues and into nearby lymph nodes.
5. Non-conductivity of zirconia:
Tissue of gum tissue in contact with zirconia is very good. Decrease bacterial growth on the surface of a zirconia due to its non-conductivity creating healthier gums around these implants.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4604158/