The pain when you suck on a tooth may be due to the development of pulpitis, which requires root canal treatment, or periodontitis, which requires periodontal treatment. 1. Pulpitis. If tooth decay has reached the pulp cavity, the pulp is exposed, it will produce severe pain to any external stimuli, when there is suction gap action will trigger tooth pain, usually need to carry out root canal treatment to remove the pulp. 2. Periodontitis. Due to poor oral hygiene can be tartar caused by periodontitis, periodontal inflammation is more serious when the gingival papilla ulceration bleeding, swelling, pain can also occur, generally need to carry out periodontal treatment, cleaning gingival subgingival tartar, oral antimicrobial drugs such as amoxicillin, metronidazole to eliminate periodontal inflammation. Sucking teeth on the pain specific need to go to the hospital to check the specific causes, and then targeted treatment, medication need to follow the doctor’s instructions.