I hv a hard abscess in molar gum.. dentist make a opening in tooth before root canal 5 days ago, nw swelling remain half.. how much time takes to go??

A few days: Once the abscess is drained, most symptoms go away quickly, within a few days. If the abscess is still in the gums, your dentist may suggest that you rinse with warm salt water a few times a day or you may need antibiotics to help fighting infection. Regardless, the abscess will not be cured unless the cause is completely eliminated.

Hard lump: The hard lump is a collection of pus. Opening tooth allows for drainage. May require antibiotics and/or surgical drainage. Can't be cured, however, without Root Canal Treatment or extraction to remove the causative infected tissues. If swelling does not completely abate, services of a root canal specialist, an Endodontist, may be in order.