I have a terrible toothache .   Which tooth is it ?   This one here .   Ar , Yes . There ’ s a big cavity .   Can you fill it ?   I ’ m afraid not . The tooth is too far gone . it'll have to be taken out .   Then I might as well have it done now .   you ’ d better wait , the gums are swollen . Take the medicine I prescribe and come back in three days . 