Effect of Integrated Apex Locator Motor Modes on Postoperative Pain in Endodontic Retreatment

NCT07527897 | Completed

• 3 other identifiers: EAL-RCT-20252025/113E-24931227-514.13.02-5708670
• Study Type: interventional
• Target: 144
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized controlled clinical trial aimed to evaluate the effect of different integrated electronic apex locator (EAL) modes on postoperative pain following nonsurgical endodontic retreatment. A total of 144 patients requiring retreatment of mandibular premolar teeth with periapical lesions were randomly assigned to four groups. In the control group, working length was determined using a conventional electronic apex locator. In the experimental groups, an integrated EAL motor was used with three different modes: apical reverse, apical slow down, and apical stop. All procedures were performed under standardized conditions. Postoperative pain was assessed using a numeric rating scale (NRS) at 6 and 12 hours and on days 1, 2, 3, 5, and 7 after treatment. The study aimed to determine whether simultaneous working length control using integrated EAL modes influences postoperative pain compared with conventional working length determination.

Conditions

Apical Periodontitis; Postoperative Pain; Endodontic Retreatment

Keywords

Electronic apex locators; Time factors; Endodontics; Retreatment; Postoperative pain

Outcome Measures

Primary Outcomes (1)

• Primary Outcome Measure

  Postoperative pain intensity was assessed using an 11-point numeric rating scale (NRS), where 0 indicates no pain and 10 indicates the worst possible pain. Pain scores were recorded at 6 and 12 hours and on days 1, 2, 3, 5, and 7 following endodontic retreatment.

  6 hours, 12 hours, and days 1, 2, 3, 5, and 7 after treatment

Study Arms (4)

Conventional Electronic Apex Locator

ACTIVE COMPARATOR

Working length was determined using a conventional electronic apex locator (Root ZX Mini) and confirmed radiographically. Endodontic retreatment procedures were completed using standardized protocols.

Device: Electronic Apex Locator

Apical Reverse Mode

EXPERIMENTAL

Working length determination and canal instrumentation were performed simultaneously using an integrated electronic apex locator motor operating in apical reverse mode during endodontic retreatment.

Device: Integrated Apex Locator Motor

Apical Slow Down Mode

EXPERIMENTAL

Working length determination and canal instrumentation were performed simultaneously using an integrated electronic apex locator motor operating in apical slow down mode during endodontic retreatment.

Device: Integrated Apex Locator Motor

Apical Stop Mode

EXPERIMENTAL

Working length determination and canal instrumentation were performed simultaneously using an integrated electronic apex locator motor operating in apical stop mode during endodontic retreatment.

Device: Integrated Apex Locator Motor

Interventions

Integrated Apex Locator Motor DEVICE

Working length determination and canal instrumentation were performed simultaneously using an integrated electronic apex locator motor (Ai Motor, Motopex, Woodpecker). The device operates with different apical control modes, including apical reverse, apical slow down, and apical stop, which automatically respond when the file reaches the predefined working length.

Also known as: Apical Reverse Mode, Apical Slow Down Mode, Apical Stop Mode

Apical Reverse Mode; Apical Slow Down Mode; Apical Stop Mode

Electronic Apex Locator DEVICE

Working length was determined using a conventional electronic apex locator (Root ZX Mini). The measurement was confirmed radiographically, and endodontic retreatment procedures were completed under standardized clinical conditions.

Also known as: Root ZX Mini

Conventional Electronic Apex Locator

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Systemically healthy patients aged between 18 and 65 years
• Patients requiring nonsurgical endodontic retreatment
• Single-rooted, single-canal mandibular premolar teeth
• Diagnosis of asymptomatic apical periodontitis
• Presence of a well-defined periapical radiolucency (PAI \> 4)
• Teeth with previous root canal treatment performed at least 4 years prior
• Root canal fillings extending to at least the apical third without overfilling

You may not qualify if:

• Patients with symptoms such as pain, swelling, or sinus tract
• Patients with a history of smoking or alcohol use
• Teeth with open apices or root resorption
• Teeth with intraradicular posts
• Teeth with insufficient coronal tooth structure
• Teeth with perforation, instrument fracture, or overfilled canals
• Teeth with root curvature greater than 30 degrees
• Teeth with periodontal disease or probing depth \>3 mm
• Cases not suitable for single-visit retreatment
• Patients who used analgesics within 12 hours prior to treatment
• Patients who used antibiotics within the last month
• Patients with cognitive impairment or psychological disorders

Sponsors & Collaborators

• Recep Tayyip Erdogan University: lead

Study Sites (1)

Recep Tayyip Erdogan University Faculty of Dentistry

Rize, Rize Province, 53000, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Periapical Periodontitis; Pain, Postoperative

Condition Hierarchy (Ancestors)

Periapical Diseases; Jaw Diseases; Stomatognathic Diseases; Periodontal Diseases; Mouth Diseases; Periodontitis; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Pain; Neurologic Manifestations; Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Masking Details: Due to the nature of the interventions, the operator could not be blinded. However, participants and the outcome assessor were blinded to group allocation. The statistician was also blinded during data analysis.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Researcher, Department of Endodontics

Model Details: Participants were randomly assigned to four parallel groups to compare conventional electronic apex locator use with three different integrated apex locator motor modes (apical reverse, apical slow down, and apical stop) during endodontic retreatment.

Study Record Dates

• First Submitted: April 7, 2026
• First Posted: April 14, 2026
• Study Start: August 13, 2025
• Primary Completion: October 10, 2025
• Study Completion: October 17, 2025
• Last Updated: April 14, 2026

Record last verified: 2026-04

Locations

TU (1)