“Do fillings hurt without an injection?”

If the cavity is inside your dentin more than likely drilling it out will be very uncomfortable. If it is only in the enamel, it may not be painful. It all depends on what tooth it is, how young/old you are, the size of the cavity and proximity to the pulp, and your pain tolerance. Typically the younger you are, the larger the pulp, ( where the nerve is) therefore more possibility if discomfort. Most dentists do not accept to perform fillings that require a lot of drilling without injections as it can be very risky and dangerous! Any sudden movement by the patient due to pain can cause trauma/ damages to the adjacent tissues such as a tooth, the tongue and even the lips. I personally have done that and drilled a tooth for a patient without anesthetics and surprisingly he did very well! But I can't recommend that to anyone based on just one case, as pain tolerance varies between patients.

It depends how deep the filling and can be evaluated with X-rays. The dentist who is doing the fillings and has seen the X-rays and examined the tooth clinically can best answer this question.
Thanks.

If there is pain, then you need to ask for anesthesia. Some fillings can be done anesthetic free. Many times this procedure is done using a laser. A lot depends on the sensitivity of your teeth as well. Again, do not hesitate to ask for an injection if there is any discomfort.

It depends on how deep it is and where it is located. If you need anesthetic, ask your dentist for it!!

If the tooth had been root canal treated, or if the nerve has receded and the cavity is not deep, you won’t feel any pain. If you are worried about not being numb, I would suggest requesting your dentist to freeze you anyway.