If I had a dime for every time a patient told me they used super glue to re-cement their crown and didn't have problems after, I'd have ZERO dimes.
Seeing these "crown cements" at Walgreen's made me very concerned. It says "Dentist Recommended" but I don't know a single dentist who would recommend these unless they were out of their minds. Yes, it seems like a quick, cheap, and easy solution, but here's why it's discouraged:
1. Risk of incorrect placement - can create crown open margins leading to tooth decay
2. Risk of crown fracture - incorrect placement can lead to a heavy bite on the crown
3. Risk of tooth fracture - incorrect placement can compromise the already weakened tooth structure
4. Inability to clean up the "cement" - cement that flows uncontrollably can end up deep in the gums, contributing to gum disease, gum abscess, further decay, and bone loss
If you have a crown (or filling) that comes off, please see a dentist - we are trained to fix these things!