Influence of Continuous Rotation Versus Reciprocation Motion of MG3 Blue Rotary File on Postoperative Pain and Intracanal Bacterial Reduction of Teeth With Necrotic Pulps.

October 28, 2026 updated by: Mohamed Farahat, Cairo University

Influence of Continuous Rotation Versus Reciprocation Motion of MG3 Blue Rotary File on Postoperative Pain and Intracanal Bacterial Reduction of Teeth With Necrotic Pulps: A Randomized Clinical Trial

he main objective of this study is to compare the impact of two different file motions-continuous rotation versus reciprocation-using the same endodontic file system (MG3 Blue rotary files) on postoperative pain and the amount of remaining bacteria inside the root canal in single-rooted teeth with necrotic pulps.

Extrusion of infected debris and persistent intracanal bacteria during root canal treatment can lead to postoperative pain and treatment complications. While various instrumentation systems have been evaluated, differences in file metallurgy, design, and number of files often obscure whether the observed outcomes are due to the movement (kinematics) or the file itself. This study aims to isolate the effect of motion kinematics by using identical rotary files in two distinct movement modes.

Participants will be randomly assigned to one of two groups:

Intervention Group (Reciprocation Motion): Canals will be prepared using MG3 Blue files operated in reciprocation motion.

Comparator Group (Continuous Rotation Motion): Canals will be prepared using MG3 Blue files operated in continuous rotation motion.

All procedures will be performed on single-rooted mandibular premolars diagnosed with pulp necrosis without apical periodontitis. Microbial samples will be collected before and after canal instrumentation to measure the reduction of cultivable bacteria (in colony-forming units, CFU/mL). Postoperative pain levels will be recorded by participants using a Visual Analogue Scale (VAS) at baseline, 24 hours, 48 hours, 72 hours, and 7 days after the first appointment.

The primary outcome of the study is post-instrumentation pain at 72 hours. Secondary outcomes include post-instrumentation pain at 7 days and the amount of remaining intracanal cultivable bacteria following canal preparation.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Not yet recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Background and RationaleA fundamental aim of root canal therapy is controlling pain and resolving apical periodontitis by thoroughly disinfecting the root canal system. Residual bacteria-particularly virulent species like Enterococcus faecalis-and their byproducts inside dentinal tubules are the leading cause of post-treatment complications and endodontic failure. During instrumentation, extruded infected debris can injure periapical tissues, triggering an inflammatory immune response and leading to postoperative pain and flare-ups. While previous research has evaluated how reciprocating versus continuous rotary systems affect postoperative pain and remaining bacteria, most studies used different file designs, cross-sections, or numbers of files, making it difficult to determine whether outcomes were driven by kinematics or file characteristics. This randomized clinical trial isolates the effect of motion kinematics by using identical MG3 Blue rotary files under two different motion dynamics. Study ObjectivesTo compare the effect of different kinematics (continuous rotation versus reciprocation) using MG3 Blue rotary files on:The intensity of postoperative pain. The amount of remaining intracanal cultivable bacteria. Trial DesignType: Parallel, single-center, randomized controlled trial (superiority framework). Allocation Ratio: 1:1. Setting: Post-graduate outpatient clinic of the Endodontics Department, Faculty of Dentistry, Cairo University, Egypt. Participants and Eligibility CriteriaInclusion Criteria:Patients aged between 18 and 50 years (males and females). Systemically healthy (ASA I or II) with no history of anti-inflammatory or antibiotic medications in the past month. Mandibular premolars presenting with a single canal and non-vital pulps (negative response to ethyl chloride cold test, absence of spontaneous pain, and no apical periodontitis). Patients capable of understanding the pain scale and signing the informed consent. Exclusion Criteria:Medically compromised patients (ASA III or IV), pregnant females, or teeth with swelling, fistulous tracts, acute/chronic periapical abscesses, grade II/III mobility, previous root canal therapy, non-restorable structure, or open/immature apices. Intervention Procedures & Protocol StepsPreoperative Evaluation: Medical/dental history collection and baseline pain assessment using a Modified Visual Analogue Scale (VAS). Local Anesthesia & Disinfection: Local anesthesia administration followed by disinfection of the oral cavity using 0.2% chlorhexidine gluconate mouthwash and rubber dam isolation. Access Cavity & Working Length: Access cavity preparation, followed by patency confirmation using stainless steel K-files (#10 and #15). Working length is determined via an electronic apex locator and verified radiographically to be 1 mm shorter than the radiographic apex. Pre-instrumentation Sampling (S1): Initial intracanal microbiological samples are collected using sterile paper points retained for 60 seconds (placed in LAL water for endotoxin assay and VMGA III transport medium for microbial cultivation). Randomized Mechanical Preparation: Patients are allocated via computer-generated randomization to one of two groups: Intervention Group (Reciprocation Motion): Canals are prepared using MG3 Blue rotary files in reciprocation motion (#20/0.10, #15/0.03, #20/0.04, #25/0.04, #30/0.04, and #35/0.04 at 300 RPM and 2 Ncm torque). Comparator Group (Continuous Rotation Motion): Canals are prepared using the same MG3 Blue rotary files in continuous rotation motion following manufacturer instructions (same sizes, 300 RPM, and 2 Ncm torque). Irrigation Protocol: Canals are thoroughly irrigated between file sizes using 3 mL of 2.25% sodium hypochlorite via a 27-gauge side-vented needle, finalized with a saline wash. Post-instrumentation Sampling (S2): Second microbial sample collected identically to S1. Canals are dried, temporarily sealed, and patients are scheduled for a 7-day follow-up appointment for root canal obturation via warm vertical compaction. Outcomes and AssessmentPrimary Outcome: Post-instrumentation pain measured at 72 hours post-procedure using the Visual Analogue Scale (VAS ranging from 0 to 10). Secondary Outcomes:Post-instrumentation pain measured at 7 days post-procedure. Amount of remaining intracanal cultivable bacteria measured via microbiological culture techniques in colony-forming units (CFU/mL) pre- and post-instrumentation.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Estimated)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
42

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • Egypt
    • Cairo Governorate
      • Cairo, Cairo Governorate, Egypt, 11251
        • Cairo University
        • Contact:
        • Principal Investigator:
          • Mohamed G Farahat, Assist Lecturer of Enndodontic

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 50 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Age between 18-50 years.
  • Males/Females.
  • Mandibular premolars:
  • Single canal.
  • Non-Vital pulps.
  • Negative response to cold pulp tester (ethyl chloride spray1).
  • Absence of spontaneous pain.
  • Absence of apical periodontitis.
  • Systemically healthy patients (ASA I or II)
  • No anti-inflammatory or antibiotic medications taken in the past month
  • Patients' acceptance to participate in the trial.
  • Patients who can understand pain scale and can sign the informed consent

Exclusion Criteria:

  • Medically compromised patients having significant systemic disorders. (ASA III or IV).
  • Teeth with swelling or fistulous tract.
  • Teeth with acute or chronic periapical abscess.
  • Mobility Grade II or III.
  • Previous root canal therapy.
  • Non-restorable teeth.
  • Immature teeth
  • Pregnant females.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: MG3 Blue rotary file - Reciprocation

MG3 Blue rotary file utilized in reciprocation motion
Device: Engine driven files utilized in reciprocation motion

MG3 blue rotary files utilized in reciprocation motion
Active Comparator: MG3 Blue rotary file - Continuous rotation

MG3 blue rotary file utilized in continuous rotation motion
Device: engine driven rotary files utilized in continuous rotation motion

MG3 Blue rotary files utilized in continuous rotation motion

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
post operative pain
Time Frame: 72 hours post instrumentation, 7 days post instrumentation

Visual Analogue Scale
72 hours post instrumentation, 7 days post instrumentation

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Intracanal bacterial reduction
Time Frame: Sample 1 before instrumentation, Sample 2 immediately after instrumentation

Microbiological Culture Technique. Sample 1 will be collected from canals after access cavity preparation and Sample 2 will be collected right after mechanical preparation of the canals.
Sample 1 before instrumentation, Sample 2 immediately after instrumentation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Cairo University

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Study Chair: Alaa Diab, Professor of Endodontics, Cairo University
  • Study Director: Sarah Samir, Associate professor, Cairo University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2026

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
January 1, 2027

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
February 1, 2027

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
October 18, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 28, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 4, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 4, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 28, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
October 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • New Endo 3-3-3

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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