Dear practo user,          It is pericoronitis that you are suffering from which happens due to the erruption of wisdom tooth. First you need to go for an x ray of that tooth, accordingly we can come to know whether the tooth is rightly errupting or impacting, accordingly the treatment can be decided i.e. symptomatic treatment/simple extraction/ surgical extraction meanwhile you should start with warm water salt gargles and medication if it pains.

Dear practo user Just do X-ray's to better visualize . Can share details though chat box for definite diagnosis and treatment planning.

Dear practo user Wisdom teeth, upper or lower,  commonly cause pericoronitis and cause gum swelling. This can subside and recur. There is no guarantee that the wisdom tooth will completely erupt. It might be impacted also.

Caries at idea of tooth OR wisdom tooth eruption. Warm salt water gargle repeatedly.only if it's relieving pain. T. Parasafe 650,if mild to moderate pain. Or T.robinaxol d, if severe pain. Antacid. If doesn't subside in two days go for antibiotic coverage.