Taking my mom for tooth extraction 1) is it okay that dentist rubs cream inside mouth before injection ? . is that a risk or i should not let the dentist rub cream inside mouth 2) can i let dentist take needle cover off or should take it off ?

Tooth Extraction: I'm not sure about about the training, certification and standards of dentists in your country, but if your mom is seeing a qualified dentist, he/she knows what to do and should be following standard of care, so no worries. Topical anesthetics are often applied to area prior to injection. Sterile needle with caps standard. If your dentist is not qualified then that's a different story.

You sound very: apprehensive. That cream is likely a topical anesthetic (to help prevent pain). In order to give an injection the needle cap needs to be removed from the syringe. The dentist or his / her staff would normally remove the needle cap - you should not be required to do any of the work in this procedure. If this is a qualified dentist - he or she will have knowledge about what to do.

Talk to the dentist: If the "cream" is a topical anesthetic ointment, that is a usual and customary procedure. The dentist or his assistant should safely uncap and recap the needle.

Not to worry: The cream is most likely a local anesthetic so the needle isn't quite a annoying. In my experience it doesn't do much but the risk of allergy or adverse reaction seems remote. Let the dentist cap and uncap the needles. Your risk of sticking yourself or contaminating the needle seems to out weigh any perceived benefits of DIY.

See below: The dentist or oral surgeon is able to extract your mother's tooth. If you feel uncomfortable about anything, speak to the provider prior to the procedure or seek another dentist. This is a routine procedure and all will go well, no worries.

OK: "Cream" is probably topical anesthetic to make the injection less uncomfortable for your mom. In most offices the Dentist is responsible for uncovering the needle. You trust the Dentist to do surgery (extraction). Trust him/her to do ancillary procedures also. If you do have questions, discuss them directly with Dentist or seek 2nd opinion.

Let the dentist: do his/her job. It will all be fine.