An interventional study of Temperature-Controlled Intracanal Irrigation in Asymptomatic Apical Periodontitis, sponsored by Medipol University. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years to 65 Years. Per ClinicalTrials.gov, last updated 2026-09-30.
Sponsored by Medipol University · Not applicable, Interventional, and Treatment
This randomized controlled clinical study will evaluate the effects of intracanal cryotherapy during root canal treatment in patients with asymptomatic apical periodontitis. The study will investigate whether the temperature of the final irrigation solution influences the biological inflammatory response and postoperative pain.
Participants will be randomly assigned to one of three groups according to the temperature of distilled water used for final root canal irrigation: 2-4°C, 8-10°C, or 22-24°C. Periapical tissue fluid samples will be collected before and after the intervention and analyzed for inflammatory and tissue-response biomarkers, including IL-1β, TNF-α, RANKL/OPG, PGE2, TGF-β, and MMP-9. Postoperative pain and analgesic use will also be recorded during the first 7 days after treatment.
The study aims to determine whether intracanal cryotherapy can reduce the inflammatory response and postoperative pain associated with root canal treatment and whether these effects vary according to the temperature of the irrigation solution.
Apical periodontitis is an inflammatory condition of the periapical tissues associated with microbial infection of the root canal system. Inflammatory mediators released during the disease process contribute to periapical inflammation, tissue destruction, and bone resorption. Intracanal cryotherapy, involving the use of a cooled irrigation solution during root canal treatment, has been proposed as an approach to modulate the inflammatory response and reduce postoperative pain. However, the biological effects of different intracanal irrigation temperatures and the potential temperature-dependent response have not been fully characterized.
This prospective, randomized, controlled clinical study will investigate the biological and clinical effects of different irrigation temperatures in patients with asymptomatic apical periodontitis requiring root canal treatment. Participants will be randomly allocated to three groups according to the temperature of distilled water used for irrigation: 2-4°C, 8-10°C, or 22-24°C. The assigned temperature-controlled distilled-water irrigation protocol will be applied consistently during both the first and second treatment sessions. The temperature of the irrigation solution will be standardized and monitored according to the participant's allocated group throughout the irrigation procedure.
Root canal treatment will be performed using a standardized two-visit protocol. During the first visit, the tooth will be isolated with a rubber dam, working length will be determined, and chemomechanical root canal preparation will be performed according to a standardized protocol. The assigned temperature-controlled distilled-water irrigation method will be used during this session. A periapical tissue fluid (PTF) sample will be collected using sterile paper points and stored under appropriate conditions for subsequent biochemical analysis. Following completion of the first-session procedures, calcium hydroxide will be placed as an intracanal medicament.
During the second treatment session, the calcium hydroxide intracanal medicament will be removed and the same temperature-controlled distilled-water irrigation protocol assigned to the participant will again be applied. Thus, participants allocated to the 2-4°C, 8-10°C, or 22-24°C group will receive distilled-water irrigation at their respective assigned temperature during both treatment sessions. A second PTF sample will be collected using sterile paper points. Root canal treatment will then be completed with obturation using gutta-percha and an endodontic sealer.
The collected PTF samples will be analyzed using enzyme-linked immunosorbent assay (ELISA) to determine the levels of selected biomarkers, including interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), receptor activator of nuclear factor kappa-B ligand/osteoprotegerin (RANKL/OPG), prostaglandin E2 (PGE2), transforming growth factor-beta (TGF-β), and matrix metalloproteinase-9 (MMP-9). These biomarkers will be used to assess changes related to inflammatory activity, bone metabolism, tissue destruction, and tissue response associated with the different irrigation temperatures.
In addition to the biochemical assessment, postoperative pain will be evaluated using a visual analog scale (VAS), and analgesic consumption will be recorded during the first 7 days following treatment. The clinical and biochemical findings will be evaluated together to determine whether temperature-controlled intracanal irrigation influences the periapical inflammatory response and postoperative pain and whether these effects vary according to irrigation temperature.
By comparing three different irrigation temperatures and evaluating both molecular biomarkers and patient-reported postoperative pain, the study aims to provide evidence regarding the biological and clinical effects of intracanal cryotherapy and to determine whether a temperature-dependent response exists.
Exclusion Criteria:
Participants assigned to this group will receive temperature-controlled distilled-water intracanal irrigation at 2-4°C during both root canal treatment sessions according to the standardized irrigation protocol.
Procedure: Temperature-Controlled Intracanal Irrigation
Participants assigned to this group will receive temperature-controlled distilled-water intracanal irrigation at 8-10°C during both root canal treatment sessions according to the standardized irrigation protocol.
Procedure: Temperature-Controlled Intracanal Irrigation
Participants assigned to the control group will receive distilled-water intracanal irrigation at 22-24°C during both root canal treatment sessions according to the same standardized irrigation protocol.
Procedure: Temperature-Controlled Intracanal Irrigation
Participants will receive temperature-controlled distilled-water intracanal irrigation during root canal treatment. According to computer-generated randomization, participants will be assigned to one of three irrigation-temperature groups: 2-4°C, 8-10°C, or 22-24°C. The assigned temperature-controlled distilled-water irrigation protocol will be applied during both treatment sessions. Irrigation conditions will be standardized across groups, with the irrigation temperature being the primary difference between the intervention groups.
Also known as: Intracanal Cryotherapy
Change in Periapical Inflammatory Biomarker Levels
Changes in interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG), prostaglandin E2 (PGE2), transforming growth factor-beta (TGF-β), and matrix metalloproteinase-9 (MMP-9) levels in periapical tissue fluid (PTF) will be assessed using enzyme-linked immunosorbent assay (ELISA). Biomarker levels obtained during the first and second treatment sessions will be compared within and between the three irrigation-temperature groups to evaluate the biological response to temperature-controlled intracanal irrigation.
Time frame: From the first treatment session to the second treatment session
Postoperative Pain Intensity Assessed Using the Visual Analog Scale
Postoperative pain intensity will be assessed using a 10-cm Visual Analog Scale (VAS), ranging from 0 to 10, where 0 represents no pain and 10 represents the worst imaginable pain. Higher scores indicate greater postoperative pain intensity. Participants will record their pain intensity after root canal treatment, and scores will be compared among the three irrigation-temperature groups.
Time frame: Day 0, Day 1, Day 3, and Day 7 after the second treatment session.
Postoperative Analgesic Consumption
Postoperative analgesic consumption will be assessed as the total number of analgesic tablets consumed by each participant during the postoperative follow-up period. Participants will record analgesic use on a daily patient record form. The type and dose of analgesic used will also be documented for descriptive purposes. The total number of tablets consumed will be compared among the three irrigation-temperature groups. Unit of measure: number of tablets.
Time frame: From Day 0 through Day 7 after the second treatment session.
Plan to share: No — Individual participant data (IPD) are not planned to be shared due to participant confidentiality and data protection considerations. Study results will be reported in aggregated and anonymized form through scientific publications and presentations.
This study is not yet recruiting, as verified in Sep 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.
Medipol University