Incidence and factors related to flare-ups in a graduate endodontic program

By Iqbal M, Kurtz E, Kohli M.

Date: 01/2009
Journal: IEJ


Purpose- investigate incidence of flare-up in large cohort of patients undergoing NSRCT.


-n=6580 patients treated by residents at U. Penn.

-categorized as having flare up when an unscheduled visit was attended due to severe pain and or swelling occurred following initiation of treatment.

-looked at history of previous pain, NSRCT vs NSRETRX, periapical diagnosis, tooth type, rotary vs. hand instrumentation, and lateral vs. vertical compaction of GP.


  • 26 patients had flare ups (0.39%)
  • Odds for developing flare up in teeth w/ PARL were 9.64 times greater than teeth w/out
  • No statistically significant difference in flare ups between 1 and 2 visit NSRCT
  • Odds increase 40 fold when NSRCT was completed in 3+ visits
  • Data could be confounded because appointment for Treatment of Flare up taken into consideration.
  • Other independent variables did not have any SS correlations.

Clinical Significance:

Presence of PA lesion single most important predictor of flare-ups during NSRCT.