Taking ibuprofen 200-400mg and acetaminophen together and around the clock, every 6 hour can yield maximal pain killing effect. Moreover, if there is evidence of infection and amoxicillin is not effective after 72 hours , switching to second line antibiotics is warranted.post op pain of crown lengthening procedure rarely lasts more than 48 hours. Oral rinse if chlohexidibe twice a day is generally recommended for oral surgical procedure.lastly, cessation of cigarette smoking is strongly recommended.
Your post op condition is extremely unusual. Cone beam CT imaging study is warranted to rule out root fracture .