An interventional study of Intracanal Cryotherapy and Standard Room-Temperature Irrigation in Postoperative Pain After Endodontic Treatment, Dental Anxiety and Root Canal Treatment, sponsored by Alanya Alaaddin Keykubat University. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-22.
Sponsored by Alanya Alaaddin Keykubat University · Not applicable, Interventional, and Supportive care
Some people feel pain after a root canal treatment. This study will test whether intracanal cryotherapy, a final rinse of the tooth with cold sterile saline, can reduce this pain compared with a room-temperature rinse.
Previous studies have suggested that intracanal cryotherapy may reduce pain after root canal treatment. In this study, we will examine its effect in a defined group of patients and explore how it works. We will measure the level of irisin, a substance with reported anti-inflammatory properties, in saliva to see whether cryotherapy changes it. We will also look at whether a person's tendency to worry about pain (pain catastrophizing) changes the effect of cryotherapy on pain, and whether dental anxiety is related to pain after treatment.
Adults aged 18 to 65 who need root canal treatment on a single-rooted lower premolar tooth will receive standard single-visit treatment. By chance, 100 participants will be placed in a cold-saline group or a room-temperature-saline group. Thirty healthy volunteers will give one saliva sample for comparison. Participants will complete questionnaires before treatment, rate their pain over the 7 days after treatment, and give saliva samples for irisin measurement.
The main questions this study aims to answer are:
Does intracanal cryotherapy lower pain after root canal treatment? Does it change salivary irisin levels? Does pain catastrophizing change the effect of cryotherapy? Is dental anxiety related to pain after treatment?
Postoperative pain after root canal treatment remains a common clinical challenge, even when the procedure is performed correctly. Intracanal cryotherapy, a final irrigation of the root canal with cooled sterile saline, has been proposed to reduce postoperative inflammation and pain by slowing local tissue metabolism and limiting the release of inflammatory mediators. Previous studies have reported a pain-reducing effect, but the biological mechanism is not fully understood.
Irisin is a myosine with reported anti-inflammatory properties, and, to our knowledge, its measurement in saliva in the context of endodontic pain has not been previously investigated. Pain catastrophizing has been associated with higher postoperative pain in previous studies, but it remains unclear whether it influences the effect of cryotherapy on pain. This study addresses cryotherapy, salivary irisin, and pain catastrophizing together within a biopsychosocial pain framework.
This is a prospective, randomized, controlled clinical trial. Adults with asymptomatic apical periodontitis in single-rooted, single-canal mandibular premolar teeth will receive single-visit root canal treatment from a single operator and will be randomly assigned to one of two groups. The intervention group will receive final irrigation with cooled saline, and the control group will receive final irrigation with room-temperature saline, using the same irrigation device. A group of healthy individuals will provide a single saliva sample for reference values.
Postoperative pain will be assessed with the Visual Analog Scale. Pain catastrophizing and dental anxiety will be assessed with validated questionnaires before treatment. Saliva samples will be collected before and after treatment to measure irisin levels.
The findings may clarify whether cryotherapy is associated with reduced postoperative pain and a change in a salivary inflammatory biomarker, whether pain catastrophizing influences the effect of cryotherapy on postoperative pain, and whether salivary irisin can serve as a non-invasive biomarker in endodontics.
5,224 studies on the registry are indexed under Pain, Postoperative; 1,154 are open to participants now.
This study's planned enrollment of 130 is above the median of 75 across 4,457 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →Alanya Alaaddin Keykubat University is the lead sponsor of 49 studies on the registry; 17 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Participants undergoing single-visit root canal treatment will receive intracanal cryotherapy using a cold irrigant delivered through a closed-system irrigation device (EndoVac) after completion of canal instrumentation and prior to obturation.
Procedure: Intracanal Cryotherapy
Participants undergoing single-visit root canal treatment will receive standard irrigation using the same closed-system irrigation device (EndoVac) with irrigant at room temperature, following the same canal instrumentation protocol as the intervention group.
Procedure: Standard Room-Temperature Irrigation
Saliva samples will be collected from healthy participants without an indication for root canal treatment, solely for the purpose of establishing normative salivary irisin reference values. These participants will not be randomized, will not undergo root canal treatment, and will not receive any study intervention.
Following completion of the standard EndoVac irrigation protocol, a group-specific final irrigation step will be performed. Sterile saline solution, refrigerated at +2°C and further cooled to 2.5°C in an ice-water bath, with temperature verified using a digital thermometer, will be delivered using the EndoVac system. A total of 20 mL of cooled saline will be applied over 5 minutes, with the micro-cannula positioned at working length to ensure effective delivery of the cold irrigant to the apical region via negative pressure.
Following completion of the standard EndoVac irrigation protocol, a group-specific final irrigation step will be performed. Sterile saline solution prepared at room temperature (20-22°C) will be delivered using the EndoVac system, following the same protocol as the intervention group. A total of 20 mL of room-temperature saline will be applied over 5 minutes, using the same technique and duration.
Postoperative Pain as Assessed by Visual Analog Scale (VAS)
Postoperative pain will be self-assessed by participants using a 100 mm Visual Analog Scale (VAS), consisting of a horizontal line where participants mark the point that best represents their level of pain intensity. The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Scores are measured in millimeters, with higher scores indicating greater pain intensity. Participants will record their VAS score in a standardized pain diary at each assessment time point, along with any rescue analgesic (paracetamol 500 mg) use, including time and dose, and any adverse events or unexpected occurrences. A blinded researcher, unaware of group allocation, will telephone participants at each designated time point to record pain scores and remind them to complete the diary.
Time frame: 24 hours after root canal treatment
Postoperative Pain as Assessed by Visual Analog Scale (VAS) at 6 Hours
Postoperative pain will be self-assessed using a 100 mm Visual Analog Scale (VAS). The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Higher scores indicate greater pain intensity.
Time frame: 6 hours after root canal treatment
Postoperative Pain as Assessed by Visual Analog Scale (VAS) at 12 Hours
Postoperative pain will be self-assessed using a 100 mm Visual Analog Scale (VAS). The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Higher scores indicate greater pain intensity.
Time frame: 12 hours after root canal treatment
Postoperative Pain as Assessed by Visual Analog Scale (VAS) at 48 Hours
Postoperative pain will be self-assessed using a 100 mm Visual Analog Scale (VAS). The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Higher scores indicate greater pain intensity.
Time frame: 48 hours after root canal treatment
Postoperative Pain as Assessed by Visual Analog Scale (VAS) at 72 Hours
Postoperative pain will be self-assessed using a 100 mm Visual Analog Scale (VAS). The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Higher scores indicate greater pain intensity.
Time frame: 72 hours after root canal treatment
Postoperative Pain as Assessed by Visual Analog Scale (VAS) at 7 Days
Postoperative pain will be self-assessed using a 100 mm Visual Analog Scale (VAS). The left end (0 mm) indicates "no pain" and the right end (100 mm) indicates "the most severe pain I have ever felt in my life." Higher scores indicate greater pain intensity.
Time frame: 7 days (168 hours) after root canal treatment
Pain Catastrophizing as Assessed by Pain Catastrophizing Scale (PCS)
Pain catastrophizing will be assessed using the Pain Catastrophizing Scale (PCS), a validated self-report questionnaire measuring the tendency to exaggerate the threat value of pain. Higher scores indicate greater pain catastrophizing.
Time frame: Baseline, prior to root canal treatment
Dental Anxiety as Assessed by Modified Dental Anxiety Scale (MDAS)
Dental anxiety will be assessed using the Modified Dental Anxiety Scale (MDAS), a validated self-report questionnaire measuring anxiety related to dental treatment. Higher scores indicate greater dental anxiety.
Time frame: Baseline, prior to root canal treatment
Salivary Irisin Level at Baseline
Salivary irisin concentration will be measured in unstimulated saliva samples collected using the passive drooling method, analyzed by enzyme-linked immunosorbent assay (ELISA).
Time frame: Baseline, prior to root canal treatment
Salivary Irisin Level at 24 Hours
Salivary irisin concentration will be measured in unstimulated saliva samples collected using the passive drooling method, analyzed by enzyme-linked immunosorbent assay (ELISA).
Time frame: 24 hours after root canal treatment
Salivary Irisin Level at 72 Hours
Salivary irisin concentration will be measured in unstimulated saliva samples collected using the passive drooling method, analyzed by enzyme-linked immunosorbent assay (ELISA).
Time frame: 72 hours after root canal treatment
Salivary Irisin Level in Healthy Reference Group
Salivary irisin concentration will be measured in a single unstimulated saliva sample collected from healthy participants without an indication for root canal treatment, using the passive drooling method and analyzed by enzyme-linked immunosorbent assay (ELISA), to establish normative reference values.
Time frame: At the time of saliva sample collection, single time point
Plan to share: No — There is no plan to share individual participant data, as no data-sharing repository or mechanism has been established for this study. Only aggregate results will be published.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is not yet recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Alanya Alaaddin Keykubat University