An interventional study of Adjunctive Photobiomodulation and Sham Photobiomodulation in Symptomatic Apical Periodontitis, Postoperative Pain and Mechanical Allodynia, sponsored by University of Minnesota. Not yet recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-21.
Sponsored by University of Minnesota · Not applicable, Interventional, and Treatment
This randomized, double-blind controlled clinical trial will evaluate whether adjunctive photobiomodulation improves recovery after nonsurgical root canal treatment in adults with teeth diagnosed with symptomatic apical periodontitis.
Participants will receive standard nonsurgical root canal treatment and will be randomized to adjunctive photobiomodulation using the Fotona LightWalker Nd:YAG laser or to an identical simulated laser procedure without laser energy delivery.
The study will evaluate mechanical allodynia using maximum occlusal force measurements comparing the treated tooth with the contralateral asymptomatic tooth. Postoperative pain will also be assessed using the Numeric Rating Scale after percussion testing.
Postoperative pain and mechanical allodynia are common concerns after nonsurgical root canal treatment, particularly in teeth diagnosed with symptomatic apical periodontitis. Mechanical allodynia may reduce functional biting capacity and contribute to discomfort even after endodontic treatment.
Photobiomodulation is a noninvasive therapeutic approach using low-level laser energy to stimulate cellular responses without producing thermal tissue damage. It has been studied for analgesic and anti-inflammatory effects, but prior endodontic studies have mainly relied on subjective pain measures. This study combines a patient-reported pain outcome with an objective functional measure of recovery using maximum occlusal force.
This study will enroll 60 adults presenting to the University of Minnesota School of Dentistry Graduate Endodontic Clinic for primary nonsurgical root canal treatment of a tooth diagnosed with symptomatic apical periodontitis. Participants will be randomized 1:1 to adjunctive photobiomodulation or sham photobiomodulation.
All participants will receive standardized nonsurgical root canal treatment in a single appointment. Participants randomized to adjunctive photobiomodulation will receive PBM using the Fotona LightWalker Nd:YAG laser immediately after obturation. Participants randomized to the sham group will undergo an identical simulated laser procedure without laser energy delivery.
Outcome assessments will be completed at baseline, 2 days after treatment, and 7 to 10 days after treatment. Mechanical allodynia will be assessed by measuring maximum occlusal force on the treated tooth and the corresponding contralateral asymptomatic tooth. Postoperative pain will be assessed using the Numeric Rating Scale in response to percussion testing.
5,224 studies on the registry are indexed under Pain, Postoperative; 1,154 are open to participants now.
This study's planned enrollment of 60 is below the median of 75 across 4,457 interventional studies indexed under Pain, Postoperative.
Browse Pain, Postoperative studies →University of Minnesota is the lead sponsor of 1,210 studies on the registry; 195 are open to participants now.
Of its 133 completed or terminated interventional studies of FDA-regulated products, 92 (69%) have results posted.
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Exclusion Criteria:
Participants will receive standard nonsurgical root canal treatment followed by adjunctive photobiomodulation using the Fotona LightWalker Nd:YAG laser immediately after obturation.
Device: Adjunctive Photobiomodulation
Participants will receive standard nonsurgical root canal treatment followed by a simulated laser procedure. The laser handpiece will be positioned identically and treatment steps will be replicated, but laser energy will not be delivered.
Device: Sham Photobiomodulation
Adjunctive photobiomodulation will be delivered using the Fotona LightWalker laser system in Nd:YAG mode immediately after completion of nonsurgical root canal treatment and obturation. The laser will be applied intraorally over the mucosa corresponding to the periapical region using a standardized protocol.
Also known as: Fotona LightWalker Nd:YAG Laser
The sham procedure will simulate photobiomodulation treatment. The laser handpiece will be positioned in the same manner and all aspects of the laser procedure will be replicated, but laser energy will not be delivered. Protective eyewear or a visual barrier will be used to maintain participant blinding.
Also known as: Simulated Laser Procedure
Change in Mechanical Allodynia Measured by Maximum Occlusal Force Difference
Mechanical allodynia will be evaluated by measuring maximum occlusal force on the treated tooth and the corresponding contralateral asymptomatic tooth. The primary endpoint is the change in the difference in maximum occlusal force between the treated and contralateral teeth from baseline to follow-up.
Time frame: Baseline
Change in Mechanical Allodynia Measured by Maximum Occlusal Force Difference
Mechanical allodynia will be evaluated by measuring maximum occlusal force on the treated tooth and the corresponding contralateral asymptomatic tooth. The primary endpoint is the change in the difference in maximum occlusal force between the treated and contralateral teeth from baseline to follow-up.
Time frame: 2 days after treatment
Change in Mechanical Allodynia Measured by Maximum Occlusal Force Difference
Mechanical allodynia will be evaluated by measuring maximum occlusal force on the treated tooth and the corresponding contralateral asymptomatic tooth. The primary endpoint is the change in the difference in maximum occlusal force between the treated and contralateral teeth from baseline to follow-up.
Time frame: 7 to 10 days after treatment
Change in Postoperative Pain Measured by Numeric Rating Scale
Postoperative pain will be assessed using the 11-point Numeric Rating Scale in response to percussion testing of the treated tooth. The secondary endpoint is the change in Numeric Rating Scale pain score from baseline to follow-up.
Time frame: Baseline
Change in Postoperative Pain Measured by Numeric Rating Scale
Postoperative pain will be assessed using the 11-point Numeric Rating Scale in response to percussion testing of the treated tooth. The secondary endpoint is the change in Numeric Rating Scale pain score from baseline to follow-up.
Time frame: 2 days after treatment
Change in Postoperative Pain Measured by Numeric Rating Scale
Postoperative pain will be assessed using the 11-point Numeric Rating Scale in response to percussion testing of the treated tooth. The secondary endpoint is the change in Numeric Rating Scale pain score from baseline to follow-up.
Time frame: 7 to 10 days after treatment
Adverse Events and Treatment-Related Complications
Participants will be evaluated for adverse events or complications related to nonsurgical root canal treatment, maximum occlusal force measurement, photobiomodulation, or simulated laser treatment.
Time frame: Treatment visit through 7 to 10 days after treatment
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.
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