Hi.. Welcome to healthcare magic... I have gone through your query and can understand your concern..... As per your complain Pan Masala stains are extrinsic stains that are tightly bound to teeth and are not removed by brushing but can be removed very well by a dentist using Scalars and you should definitely visit your dentist and get the scaling of the teeth done to get the stains removed, along with it you should also stop chewing pan masala as it is very harmful and persistent use can lead to fatal conditions like oral cancer.. As far as damage to teeth is concerned due to scaling you need not to worry as during scaling a very minute amount of minerals are removed from the teeth which are recovered in 3 to 4 days or maximum a week from the minerals present in saliva and a duration of one year is enough after which you can get the scaling of the teeth done without any harm to the teeth.. They cannot be removed by you on your own and a dentist visit is must .. Maintain a good oral hygiene by brushing your teeth twice a day [morning and night],gargle after meals and use of fmouthwash and flossing is helpful in maintaining a good oral hygeine.. Hope this information helps.. If you find the answer helpful please give me a Five Star Review and click on found the answer helpful as a token of appreciation.. Thanks and regards.. Dr.Honey Nandwani Arora..