dental pain

[mike13]

I know a couple of dentists frequent this forum and would appreciate their advice.About a year ago i had root canal treatment in one of the two front teeth.Seemed to settle the pain,but a few months later the pain returned,antibiotics started but no use.Then had the root canal done again last month,again seemed to settle,but this weekend pain has returned,not excruciating but there all the time.What will my dentist do now and what could be the problem.

tia