Effects of Irrigation Activation on Clinical Outcomes of Root Canal Treatment

Primary outcomes

1. change from baseline postoperative pain at 1 week

   Time frame: 24 hours, 48 hours and 1 week postoperatively

   Pain was measured using a modified visual analogue scale (VAS) with 4 levels, as follows: 1, no pain; 2, slight pain (mild discomfort, no treatment needed); 3, moderate pain (pain required analgesics for relief); 4, severe pain (pain and/or swelling not relieved by simple analgesics and required unscheduled visit). Patients were provided forms and asked to record preoperative pain as well as pain at 24 hours, 48 hours and 1 week postoperatively, and to note down the number of analgesics taken. Patients returned their completed forms at their 1-week follow-up visits.

2. change from baseline periapical index at 1 year

   Time frame: Clinical and radiographic examinations were performed on the 1 day of treatment,1 day after treatment and 1 year after treatment.

   Periapical tissue was evaluated using a 5-point periapical index (PAI) (Ørstavik et al. 1986) and scored as follows: 1: Normal periapical structures; 2: Small changes in bone structures; 3: Changes in bone structure with some mineral loss; 4: Periodontitis with well-defined radiolucent area; 5: Severe periodontitis with exacerbating features. If scores varied among roots in the same tooth, the highest score was recorded for that tooth. Similarly, if scores varied between observers for the same tooth, the higher score was recorded.

   Treatment was considered successful if the patient had no discomfort, no percussion/palpation pain, no sinus tract, no mobility or associated soft-tissue swelling, and a PAI score of ≤ 2. Treatment was considered a failure if the patient could not perform normal masticatory functions, experienced discomfort and percussive pain upon examination, and/or had a PAI score of ≥ 3 .