title: Prospective case controlled clinical study of post-endodontic pain after rotary root canal preparation performed by a single operator.
abstract: OBJECTIVE
  The aim of this study was to assess the influence of the shaping technique on incidence, intensity, duration and type of postoperative pain (PP).
  
  
  METHODS
  Root canal treatments were carried out with rotary instrumentation (n=80) during a single-visit, and data about pre-treatment conditions were collected. Patients were given a questionnaire to record the presence or absence of post-endodontic pain, its duration and level of discomfort. A matching patient (same pre-treatment conditions but manual instrumentation) was randomly selected from a pool (n = 374) and assigned to the control group. A total of 44 pairs of patients matched completely and were included in the study. Incidence (yes/no) of PP was assessed using Chi-square tests, intensity (mild, moderate, severe) with trend tests and duration (days) with Mann-Whitney U tests.
  
  
  RESULTS
  A significantly greater proportion of the patients in the control group reported pain than did patients in the rotary shaping group (p < 0.05). However, pain duration was shorter (p = 0.008) in the control group. Differences in level of discomfort were not statistically significant.
  
  
  CONCLUSIONS
  The results of this prospective in vivo study suggest that a higher incidence of PP should be expected after manual root canal preparation. However a second major finding of the study is that when present, PP after a rotary canal preparation is expected to last longer.
  
  
  CONCLUSIONS
  There has been an increase in the use of rotary techniques among dentists in recent years. The present study analyses the differences in the incidence and characteristics of postoperative pain that should be expected after rotary canal preparation compared to traditional manual methods that had not been reported yet.
authors.affiliation: Department of Endodontics, University of the Pacific, Arthur A. Dugoni School of Dentistry, USA. Electronic address: aa@ana-arias.com.
authors.forename: Ana
authors.initials: A
authors.lastname: Arias
authors.affiliation: Department of Conservative Dentistry, School of Dentistry, Complutense University, Madrid, Spain.
authors.forename: José C
authors.initials: JC
authors.lastname: de la Macorra
authors.affiliation: Department of Odontology, School of Medicine, CEU San Pablo University, Madrid, Spain.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Azabal
authors.affiliation: Department of Conservative Dentistry, School of Dentistry, Complutense University, Madrid, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Hidalgo
authors.affiliation: Department of Endodontics, University of the Pacific, Arthur A. Dugoni School of Dentistry, USA.
authors.forename: Ove A
authors.initials: OA
authors.lastname: Peters
mesh_terms: D000328:Adult; D003754:Dental High-Speed Equipment; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D010149:Postoperative Pain / Q000453:epidemiology; D011446:Prospective Studies; D018915:Root Canal Preparation / Q000379:methods*
keywords: Manual preparation; Pain duration; Post-endodontic pain; Postoperative pain; Rotary preparation