Investigating the Effectiveness of Photobiomodulation Therapy on Pain Reduction After Miniscrew Placement in Orthodontic Patients: A Randomized Clinical Trial

To evaluate the effectiveness of photobiomodulation therapy in reducing pain following miniscrew placement in orthodontic patients using a split-mouth design.

Randomized, double-blind, placebo-controlled, split-mouth clinical trial with 18 patients; randomization using block sizes of 2, 4, and 6 via sealedenvelope.com; not applicable for clinical trial phase.

The study is conducted in private orthodontic clinic on 18 patients requiring miniscrew placement. Photobiomodulation or placebo is applied post-miniscrew insertion by a trained operator. Participants and outcome assessors are blinded using identical laser application protocols. Data collection includes pain assessment via Visual Analog Scale and gingival index evaluation.

Inclusion criteria: Patients requiring miniscrew placement during orthodontic treatment, no prior orthodontic treatment before the study, no radiographic evidence of bone loss, no active dental caries, no periodontal diseases, adequate oral hygiene; Exclusion criteria,: hypersensitivity to laser light, pregnancy.

Intervention group: Photobiomodulation therapy using a diode laser with 940 nanometers wavelength, 300 milliwatts power, and 31.7 joules per square centimeter energy density applied for 180 seconds to the tissue surrounding the miniscrew on one side of the mouth. Control group: Placebo with inactive laser applied for 180 seconds to the tissue surrounding the miniscrew on the opposite side of the mouth with identical appearance and procedure.

Pain intensity measured by Visual Analog Scale immediately after miniscrew placement; at 1 hour; 12 hours; 24 hours.

Randomization is performed using two series of random numbers in blocks of 2, 4, and 6, generated via www.sealedenvelope.com. The first series determines the side of the mouth for intervention, and the second series determines the type of intervention (active laser or placebo). Allocation concealment is ensured using sealed opaque envelopes, each containing codes A or B. Randomization is conducted by an independent researcher not involved in treatment or assessment. Patient enrollment is performed by an orthodontist, and intervention allocation is conducted by a trained assistant.

This study is designed as a double-blind trial. Participants are unaware of the intervention allocation (active laser or placebo) on each side of the mouth, as the laser device used for both active and placebo interventions has identical appearance, sound, and application procedure. Outcome assessors, responsible for evaluating pain using the Visual Analog Scale (VAS) and assessing the gingival index, are blinded to the intervention allocation, as data collection forms and clinical examinations do not indicate which side received the active or placebo treatment. Blinding is maintained through standardized laser application protocols and sealed randomization codes managed by an independent researcher. The clinical caregiver (orthodontist administering the intervention) and the data analyst are not blinded due to the requirements of intervention delivery and data analysis.

Individual Participant Data, Study Protocol, Statistical Analysis Plan, Informed Consent Form, Clinical Study Report, Analysis Codes, and Data Dictionary: The individual participant data (IPD) will include de-identified data on pain intensity (Visual Analog Scale scores), gingival index, inflammation, redness, and blisters, as well as demographic variables (age, gender) and pain catastrophizing scale scores. The study protocol will detail the methodology, including the split-mouth design, photobiomodulation parameters, and outcome assessments. The statistical analysis plan will describe the statistical tests (e.g., paired t-test, Wilcoxon, GEE) and software (SPSS) used. The informed consent form will be shared in its final approved version. The clinical study report will summarize findings post-study completion. Analysis codes will include SPSS syntax for all statistical analyses. The data dictionary will define all variables, their coding, and measurement units.

Data and documents will be available starting six months after the publication of the primary study results and will remain accessible for five years thereafter.

Researchers affiliated with academic or scientific institutions, including universities and research centers, who are conducting non-commercial research related to orthodontics, pain management, or photobiomodulation.

Data and documents may be used for secondary analyses, meta-analyses, or methodological reviews related to orthodontic pain management or photobiomodulation. Access requires a formal request outlining the research objectives, analysis plan, and ethical approval for the proposed study. Recipients must sign a data use agreement ensuring confidentiality, non-commercial use, and no attempt to re-identify participants. Data sharing will comply with ethical standards and Iranian regulations.

Requests should be submitted via email to Dr. Fatemeh Azizi at azizi3889@gmail.com. Alternatively, contact the Research Office at Kermanshah University of Medical Sciences, Shahid Beheshti Boulevard, Kermanshah, Iran, phone: +98 83 34276301.

Applicants must submit a written request detailing the research purpose, analysis plan, and ethical approval. The request will be reviewed by the study’s principal investigator (Dr. Fatemeh Azizi) and the Kermanshah University of Medical Sciences Ethics Committee within four weeks. If approved, a data use agreement will be signed, and data/documents will be shared via a secure electronic platform within two weeks of agreement. Applicants will be notified of the decision and expected timeline.

All shared data will be anonymized to protect participant privacy. The study team reserves the right to reject requests that do not align with the study’s ethical or scientific objectives. Shared data must not be redistributed without prior approval.