Post-operative Pain and Apical Healing After Root Canal (re)Treatment With Laser-activated Irrigation Versus Sonic or no Activation

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

• Ages 18 years and older
• All sexes
• No healthy volunteers
• Adult, Older adult

Trial locations and contacts

2 sites in 1 country. Contact the study team or a site near you to ask about taking part.

About this study

Official title: Post-operative Pain and Apical Healing After Root Canal (re)Treatment With Laser-activated Irrigation Versus Sonic or no Activation: a Multi-centre Randomised Controlled Clinical Trial

Conditions

Apical Periodontitis, Post Operative Pain, Acute

Being tested

sonically activated irrigation, laser activated irrigation, conventional needle irrigation

Medical subject headings

Periapical Periodontitis, Pain, Postoperative

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

• sonically activated irrigationDevice

  The irrigant is activated after mechanical preparation with a plastic Eddy-tip (f = 6000 Hz) inserted up to 1 - 3 mm short of the working length. Three 20 s activation cycles are performed per canal, with 2 mL irrigation in each root canal between the cycles.

• laser activated irrigationDevice

  The irrigant is activated after mechanical preparation with a pulsed Er:YAG laser (Fotona Fidelis III, PIPS, E = 20 mJ, f = 20 Hz, t = 50 μs). These settings result in a power of 0.4 W. Due to the high absorption of the Er:YAG wavelength in the irrigant, mechanical effects occur (cavitation), rather than thermal effects. As a result, the risk of thermal damage is negligible. The tip of the laser is kept at the canal orifice, but not inserted into the root canal. During activation, irrigant is continuously added to the pulp chamber, so the root canals and pulp chamber are consistently immersed in irrigating solution. Three 20 s activating cycles per orifice are executed, with intermittent flushing of the root canal with 2 mL irrigant.

• conventional needle irrigationOther

  The root canals are irrigated with 3% NaOCl, using a 27G notched needle, adapted to a 3 mL syringe and inserted up to 2 - 3 mm short of working length. Two millilitres of irrigant are used between the different instruments.

What is being measured

The primary outcome is the main question the study is designed to answer.

1. post-operative pain

   The post-operative pain immediately after completion of treatment is scored with the Visual Analogue Scale (VAS). Patients are asked to fill out a pain diary 6 hours, 24 hours, 48 hours, 72 hours and 96 hours after treatment with a pain score on the VAS.

   Measured: Post-operative pain is scored immediately after the treatment and 6 hours, 24 hours, 48 hours, 72 hours and 96 hours after treatment.

2. tooth survival

   presence of the treated tooth inside the mouth

   Measured: up to 2 years post-treatment

3. apical healing

   The pre-operative and recall periapical radiographs are compared for the periapical index (PAI). On the radiographs, the apical periodontitis lesion is outlined and the surface of the lesion is calculated using software. The surface of the apical periodontitis lesion on the follow-up radiograph is compared to the pre-operative radiograph. Teeth are categorized into the following three outcome categories based on analysing the change in the PAI:

   • Strict radiographic success (healed teeth): absence of clinical signs or symptoms, and PAI-score of 1 or 2 at follow-up.
   • Loose radiographic success (healing teeth): absence of clinical signs or symptoms, and a lower PAI-score (or smaller surface of the lesion) compared to the pre-operative radiograph.
   • Failure (non-healing): clinical signs or symptoms (including pain, swelling, sinus tract), or asymptomatic with an unchanged PAI-score (or surface of the lesion), or increase in PAI-score (or surface of the lesion) at follow-up.

   Measured: up to 2 years post-treatment

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

1. First posted20 Oct 2026
2. Study startOct 2026 (estimated)
3. Primary completionAug 2029 (estimated)
4. Study completionAug 2029 (estimated)

Resources

• Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
• Other trials for Apical PeriodontitisStudies of the same condition, open and under way.
• What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.