Flare-Up Rate in Pulpally Necrotic Molars in One- Visit Versus Two-Visit Endodontic Treatment

By Eleazer PD, Eleazer KR

Date: 11/1998
Journal: JOE


•Purpose: To compare the flare up rate in one-visit versus two-visit endodontic treatment.

•N=  402 consecutive patients


  • Only pulpally necrotic and first and second molars without detectable sinus tracts were considered.
  • Endodontic treatment was performed with step-back filing to at least a #30 diameter. During instrumentation, RC Prep and 0.5% NaOCl were used.
  • Metacresylacetate an intracanal medication with two-visit therapy.
  • The patient served as his own control when the same individual qualified in both treatment groups.
  • Antibiotic treatment was often ordered if exudate was present.

Most highlighted Results: 

1.8% flare-ups occurred in the two-visit group versus 3% flare-ups for the one-visit group.

2.No significant differences regarding age, gender, maxillary or mandibular molar, and first or second molar. No significant differences arose regarding antibiotic use.

3.In a second comparison, one-visit patients who had previously received two-visit treatment for a different pulpally necrotic molar served as their own control. No significant differences were present in this subgroup of 17 patients.

Clinical significance: 

A higher chance of flare up in 2 visit treatment than single visit.