My thinking is that I could take a similar approach as has been done for making skin cream.
See: DIY Rapamycin skin cream
I would dissolve the rapamycin in a small amount of transcutol (say 10 g) and then after that I would mix it into a non-tube toothpaste (e.g 90 grams) like this one below (simply because its easier to mix and then put it back into the same container):
It seems that transcutol would be safe in this type of application:
I suspect effective treatment of perio disease with rapamycin will require either systemic delivery or direct delivery into the periodontal pockets. There are minocycline products that are in powder or gel form that are directly injected subgibgival. I would expect to see a rapamycin version of the same.
Typically a toothpaste isn’t going to reach the pocket depths where the medication needs to act.
I used to have gum disease and cavities, but then I started brushing twice a day and using an anti-bacterial toothpaste and didn’t have any more problems with either. I think Rapamycin may be a little bit too much in this case and would recommend the anti-bacterial versions of popular toothpaste unless the periodontal disease is quite advanced. Then again, I am not a dentist so take my advice with a grain of toothpaste…
I don’t know how periodontitis works in mice but I doubt this would work in humans. It is well known that in humans it’s not the periodontogenic bacteria that cause the destruction of attachment and bone but an improper immune response to them. Rapa might mitigate that but that still leaves the subgingival calculus as a big mechanical barrier for new bone growth and attachment. I didn’t read the paper but looked at the pics and saw that the mice had vertical bone loss maybe also due to presence of the bacteria on a tiny mouse tooth without much calculus? Anyway in humans a good scaling and root planing often restores some of the attachment and bone loss in humans too already