If you truly believed your product is better you’d offer a money back guarantee. Build something you can stand behind proudly, not retreat into disclaimers when someone has been curious enough to veer off the beaten path (and against dentist recommendations) to give a new product on the market a chance, they shouldn’t take all the loss when dissatisfied. Again, companies that build products they can stand behind proudly offer a money back guarantee.
I’ve told folk I know not to buy the product!