Hello, I can understand your concern. Usually swelling does not develop after starting pulpotomy procedure. However, in some cases, the body reacts to the medications and disinfectants used in the procedure and presents as an allergic reaction which makes the lip swell. Sometimes if anesthesia is given in the front teeth area, then lip swelling can happen too which will subside on its own in some days. I would advise you not to complete the procedure until the swelling is completely healed as swelling sometimes presents underlying infection too. If the dentist has declared that the pulpotomy procedure is finished, then you should wait for about a week for swelling to subside. If it is not subsided then, go back to him/her or another dentist and get the filing material removed to reduce the swelling and after the swelling is subsided, the treatment can be completed. I hope this information helps you. Thank you for choosing HealthcareMagic. I wish your son feels better soon. Best, Dr. Viraj Shah