I have noticed a very slight increase in dental implant failure during the 18 months following the start of the Covid-19 epidemic. Although this number is still less than 1%.  There is certainly a possibility that this is due to some other random factor, but it is also possible that this, as well, has Covid-19 as a contributing factor. (J Oral Maxillofac Surg 79: 1197-1198, 2021).

I have been placing dental implants for over 35 years and during those years dental implants and bone regenerative procedures have been some of the most reliable and predictable treatments that we perform. As I have stated before, we are responsible in our approach, we are highly trained and experienced, and we perform “high yield” procedures.

Three methods/pathways have been postulated to explain the possible causes for the decreased success rate for dental implants in the presence of Covid-19 in this article. It is further postulated that active disease would not necessarily have to be present. The three pathways that are spoken about are: 1.) alterations in the ACE2 pathway, 2.) the inflammatory cytokine “storm” and 3.) microvascular dysfunction.

ACE2 is a receptor for the spike glycoprotein of the coronavirus. This receptor promotes a cell reaction in the cells that both absorb and form bone. This process is also active in the remodeling of bone in the jaws. It has been speculated that the coronavirus combines with the ACE2 receptor resulting in an interference in this pathway and this could affect the way bone heals around an implant.

The inflammatory cytokine “storm” describes a release of certain inflammation factors into the body tissues. IL-1β, IL-6, TNF-α, G-CSF, IP-10, MCP-1, MIP-1α, have all been detected in patients with Covid-19, especially those that require ICU admission. These factors may enhance bone resorption. When not under control, the levels of these cytokines may result in bone loss and decreased bone formation which can also lead to problems with healing around an implant.

There is a lot of initial evidence that the smallest blood vessels or microvascular are affected by Covid-19. In some studies, Covid-19 showed up to a 90% reduction in vascular density which was almost exclusively for very small capillaries. Again, dental