Master apical file size – smaller or larger: a systematic review of healing outcomes.

By Aminoshariae A. & Kulild J

Date: 07/2015
Journal: JOE


Purpose: to determine whether apical enlargement affected the healing outcome in patients undergoing root canal treatment.

•N= 4 articles.


•A PICO strategy was developed to identify previously published studies dealing with apical size of canal and microbial reduction.

Inclusion criteria:

  • In vivo human studies articles from 1950 to 2014 which reported clinical and radiographic outcomes.
  • The comparison between different apical sizes.
  • The sample size was given in the study.
  • The effect of enlargement on healing was measured as a primary objective.
  • The patients were evaluated for 12 months or longer.

Most highlighted Results:

•The authors reported that enlargement of the canal to 3 sizes larger than the FABF was adequate. (Saini et al. 2012)

•The overall success rate in patients with necrotic pulps and periapical lesions 90% when increasing the apical preparation 3-4 sizes larger than the FABF.  (Souza et al. 2012) 

•No significant difference between the results in roots that were enlarged with sizes 20–40 or in roots that were enlarged with sizes 45–100. The overall success rate was 91%.  (Kerekes et al. 1979) 

Clinical significance:

The best current available clinical evidence would suggest that, for patients with necrotic pulps and periapical lesions, 

greater enlargement of the apical size would result in an increased healing outcome.