Ultrasonic Activated Irrigation and Intracanal Cryotherapy for Reducing Pain After Root Canal Treatment

Effect of Using Ultrasonic Activated Irrigation, With and Without Intracanal Cryotherapy, on Post-Operative Pain After Single Visit Root Canal Treatment of Teeth With Symptomatic Irreversible Pulpitis: A Randomized Controlled Trial

This randomized controlled trial aims to evaluate the effect of ultrasonic activated irrigation with and without intracanal cryotherapy on postoperative pain following single-visit root canal treatment in teeth with symptomatic irreversible pulpitis.

Participants requiring root canal treatment will be randomly allocated into two groups. One group will receive ultrasonic activated irrigation alone, while the other group will receive ultrasonic activated irrigation followed by intracanal cryotherapy. Postoperative pain will be assessed at predetermined time intervals using a standardized pain assessment scale.

The findings of this study may help identify effective strategies for reducing postoperative pain after root canal treatment and improving patient comfort and treatment outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: Symptomatic Irreversible Pulpitis and Post Operative Pain
• Intervention / Treatment: Procedure: Ultrasonic Activated Irrigation; Procedure: Intracanal cryotherapy

Detailed Description

Postoperative pain remains one of the most common complications following root canal treatment and may negatively affect patient comfort and treatment acceptance. Various factors, including preoperative status, instrumentation techniques, and irrigation protocols, influence the incidence and severity of post-endodontic pain.

Ultrasonic activated irrigation (UAI) enhances the effectiveness of irrigants by generating acoustic streaming and cavitation, thereby improving debris removal, smear layer elimination, and disinfectant penetration into the root canal system. Intracanal cryotherapy, which involves the application of cold saline as a final irrigant, has been proposed as a non-pharmacological method to reduce postoperative pain by decreasing tissue temperature and exerting anti-inflammatory effects.

This study is a single-center, parallel two-arm, single-blinded randomized controlled trial conducted at the Department of Operative Dentistry and Endodontics, Sardar Begum Dental College, Peshawar, Pakistan. A total of 60 patients aged 20 to 50 years diagnosed with symptomatic irreversible pulpitis in mandibular first or second molars will be enrolled.

Eligible participants will be randomly allocated into two groups using a computer-generated randomization sequence with allocation concealment through sealed opaque envelopes. Group A (control group) will receive ultrasonic activated irrigation without intracanal cryotherapy, whereas Group B (intervention group) will receive ultrasonic activated irrigation followed by intracanal cryotherapy using 0.9% saline at 1.5-2.5°C for 5 minutes.

All treatments will be performed in a single visit under local anesthesia and rubber dam isolation using standardized clinical protocols. Root canal preparation will be carried out using the ProTaper Universal rotary system. Ultrasonic activation will be performed for one minute per canal. Following obturation and permanent restoration, postoperative pain will be assessed using a 10-point Visual Analogue Scale (VAS).

Pain scores will be recorded at 12, 24, 48, and 72 hours postoperatively through telephone follow-up by a blinded assessor. The primary outcome measure is postoperative pain intensity. Analgesic consumption and adverse events will also be documented.

The findings of this study may provide evidence regarding the effectiveness of intracanal cryotherapy as an adjunct to ultrasonic activated irrigation for reducing postoperative pain following single-visit root canal treatment in teeth with symptomatic irreversible pulpitis.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 1. Patients who are medically fit (ASA Physical Status I) and aged between 20 and 50 years will be recruited for the study.

  2. Mandibular first or second molars exhibiting signs of symptomatic irreversible pulpitis, identified through an extended sensitivity to cold testing and/or a positive electric pulp test.

  3.Vital pulp with no signs of apical pathology (normal periapical radiograph, no swelling, sinus tract, or mobility).

  4. Mature roots with closed apices and no prior root canal treatment. 5. Willing to undergo single-visit treatment and comply with follow-up.

Exclusion Criteria:

• 1.Use of analgesics or NSAIDs within 12 hours prior to treatment. 2.Pregnant or lactating women. 3.Presence of systemic illness or allergy to any materials used in the study. 4.Teeth with:

  • Non-vital pulp, periapical radiolucency, or sinus tract.
  • Mobility > Grade I or periodontal pockets > 5 mm.
  • Resorption, calcification, or non-restorable crown structure. 5.Third molars (wisdom teeth). 6.Endodontically treated tooth. 7.Inability or unwillingness to follow study instructions or complete follow-up.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Ultrasonic Activated Irrigation Without Intracanal Cryorherapy; Participants assigned to this arm will undergo single-visit root canal treatment under local anesthesia and rubber dam isolation. Root canal preparation will be performed using the ProTaper Universal rotary system. Irrigation during instrumentation will be carried out using 5.25% sodium hypochlorite with ultrasonic activation for one minute per canal. At the final irrigation stage, 10 mL of room-temperature 0.9% saline will be delivered over 5 minutes. The canals will then be obturated and permanently restored in the same visit.	Procedure: Ultrasonic Activated Irrigation; Ultrasonic activation of 5.25% sodium hypochlorite was performed for one minute per canal, 1 mm short of the working length, during single-visit root canal treatment to enhance irrigant penetration and canal debridement.
Experimental: Ultrasonic Activated Irrigation With Intracanal Cryotherapy; Participants assigned to this arm will undergo single-visit root canal treatment under local anesthesia and rubber dam isolation. Root canal preparation will be performed using the ProTaper Universal rotary system. Irrigation during instrumentation will be carried out using 5.25% sodium hypochlorite with ultrasonic activation for one minute per canal. At the final irrigation stage, 10 mL of cold (1.5-2.5°C) 0.9% saline will be delivered 1 mm short of the working length over 5 minutes as intracanal cryotherapy. The canals will then be obturated and permanently restored in the same visit.	Procedure: Ultrasonic Activated Irrigation; Ultrasonic activation of 5.25% sodium hypochlorite was performed for one minute per canal, 1 mm short of the working length, during single-visit root canal treatment to enhance irrigant penetration and canal debridement.; Procedure: Intracanal cryotherapy; Intracanal cryotherapy was performed by delivering 10 mL of cold 0.9% saline (1.5-2.5°C) passively 1 mm short of the working length over 5 minutes as the final irrigation step during single-visit root canal treatment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Pain Intensity	Postoperative pain intensity will be assessed using a 10-point Visual Analogue Scale (VAS). Pain scores will be recorded through telephone follow-up at 12, 24, 48, and 72 hours after completion of single-visit root canal treatment.	12,24,48 and 72 hours after the completion of single-visit root canal treatment

Collaborators and Investigators

• Sponsor: Dr Arsalan Ali Khan
• Investigators: Study Chair: Shakeel Ur Rehman Khattak, BDS,BSc,MHR,FCPS, Sardar Begum Dental College,Gandhara University,Peshawar,Pakitstan

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): January 1, 2027
• Study Completion (Estimated): March 1, 2027

Study Registration Dates

• First Submitted: June 17, 2026
• First Submitted That Met QC Criteria: June 17, 2026
• First Posted (Actual): June 23, 2026

Study Record Updates

• Last Update Posted (Actual): June 23, 2026
• Last Update Submitted That Met QC Criteria: June 17, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Postoperative Pain; Symptomatic irreversible pulpitis; Intracanal Cryotherapy; Ultrasonic Activated Irrigation; Single-visit Root Canal Treatment
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Postoperative Complications; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative
• Other Study ID Numbers: GU/Ethical Committee/2025/248

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be publicly shared because this is an investigator-initiated academic study, and no formal data-sharing plan has been established. Participant confidentiality and privacy will be maintained in accordance with institutional ethical guidelines.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No