Influence of coronal preflaring on the accuracy of working length determination methods: A comparative clinical study

Girish Babu KL¹ image, Geeta Maruti Doddamani2 image, Kavyashree Gururaj Hebbar3 image, Jayalakshmi C4 image, Premkishore K5 image

Highlights

Coronal preflaring may improve working length determination in primary teeth by enhancing straight-line access and reducing coronal interferences that limit file advancement.

Coronal preflaring significantly increased the accuracy of working length determination, especially when combined with initial canal enlargement, producing values closer to actual root canal length.

Routine incorporation of coronal preflaring in pediatric endodontics can enhance measurement reliability, procedural efficiency, and overall clinical outcomes during pulpectomy.

Abstract

Aim: Coronal preflaring (CPF) is widely recognized as a critical operative maneuver for achieving a straight-line approach to the canal orifice and its initial curvature and to improve the precision in working length (WL) determination. This study aimed to evaluate the effect of CPF on the accuracy of various WL determination methods in primary teeth. Methods: Forty primary mandibular second molars indicated for extraction were selected. WL was assessed using conventional radiography (CR), digital radiovisiography (DR), and an electronic apex locator (EAL) at three procedural levels: prior to CPF, following CPF, and after the combined intervention of CPF with initial canal enlargement. Subsequently, the teeth were extracted, and the actual root canal length (ARCL) was determined using a stereomicroscope. Data were analyzed using One-way ANOVA and Chi-Square tests. Results: In the absence of CPF, WL measurements obtained via CR, DR, and EAL were consistently shorter than the ARCL. Following CPF and the combined CPF and initial canal enlargement intervention, a progressive increase in WL values was observed, demonstrating closer alignment with the ARCL. Conclusions: CPF significantly improves the clinically acceptable accuracy of WL determination in primary mandibular second molars and should be considered an essential step in pediatric endodontics.

Keywords: Coronal Preflaring; Digital Radiography; Electronic Apex Locator; Radiography, Dental; Working Length

Author Affiliations

  1. Professor, Department of Dentistry, Hassan Institute of Medical Sciences, India (Correspondence:docgirish77@gmail.com)
  2. Professor, Department of Orthodontics, Dr. Syamala Reddy Dental College Hospital and Research Centre, India
  3. Former Junior Resident, Department of Dentistry, Hassan Institute of Medical Sciences, India
  4. Junior Resident, Department of Dentistry, Hassan Institute of  Medical Sciences, India
  5. Professor, Department of Pedodontics and Preventive Dentistry, Rungta College of Dental Sciences and Research, India
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Article Info

Contemp Pediatr Dent 2025:6(3):240-253

Received: 31 October 2025

Accepted: 26 December 2025

Online First: 28 December 2025

DOI: 10.51463/cpd.2025.68

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					Girish Babu KL, Geeta Maruti Doddamani, Kavyashree Gururaj Hebbar, Jayalakshmi C, Premkishore K. Influence of coronal preflaring on the accuracy of working length determination methods: A comparative clinical study. Contemp Pediatr Dent 2025:6(3):240-253

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