While these treatments are currently focused on patients with congenital tooth deficiency, Takahashi hopes the treatment will be available for anyone who’s lost a tooth.

In other earlier reports it is also mentioned that the successes in animal trials also were with congegeniaal tooth deficiency. So the hopes of this researcher are not backed by results. And though I'm no expert on any field related to this, I can't see how this would work for people who lost teeth.

Quick edit; an earlier source