SANOS ® is not for the cosmetic visible crown of the tooth, it is for keeping plaque and tartar from forming under the gums. (allaccem.com)
If left untreated, the lesions will obliterate the entire crown of the tooth and gum tissue will grow over the remaining root tips. (nationalpetdentalassociation.com)
From this X-ray you can see this is a resorped lesion and you can see the whole crown of the tooth is being eaten away by this process and needs to be extracted. (thedrakecenter.com)