Barreto-Santos, J., et al. - Photobiomodulation and the Stability of Orthodontic Mini-Implants: A Systematic Review

This systematic review of five randomized trials suggests that diode laser photobiomodulation may improve the stability of orthodontic mini-implants, but only three of the five trials observed this effect. According to the authors, the small number of trials and the significant variability in irradiation protocols preclude any firm clinical recommendations.

What this study measured

Orthodontic mini-implants serve as temporary skeletal anchors. Their advantage lies in their minimally invasive placement and the fact that they do not rely on patient cooperation. Their success, however, depends on maintaining sufficient primary and then secondary stability throughout the entire course of treatment. Diode laser photobiomodulation is proposed as a noninvasive adjunct believed to support healing and peri-implant bone remodeling.

The authors conducted a systematic review following the PRISMA methodology, searching PubMed, EBSCO, Scopus, and ScienceDirect, and selecting randomized clinical trials published over the past ten years. Five trials met the eligibility criteria, involving a total of 89 participants and 178 mini-implants. The risk of bias was assessed using the Cochrane RoB 2 tool, and the certainty of the evidence was assessed using the GRADE method.

Key Findings

The results are mixed and do not allow for a clear-cut conclusion.

• Five randomized clinical trials were included, involving 89 participants and 178 orthodontic mini-implants.
• Three studies report improved stability following diode laser photobiomodulation.
• Two studies found no significant differences compared with the control group.
• Wavelengths used in the tests: 618 to 940 nm.
• Stability measured using resonance frequency analysis (ISQ) and Periotest values; the test also measured insertion and removal torques.
• Overall certainty of the evidence was rated as moderate according to GRADE, due to inconsistencies among trials and methodological heterogeneity.

Most of the trials had a low risk of bias, although there were reservations regarding allocation concealment and blinding.

How photobiomodulation works for this indication

The rationale put forward by the authors is based on the effect of red and near-infrared light on bone healing. The absorption of these wavelengths by mitochondrial chromophores has been associated in the literature with a modulation of cellular activity and bone remodeling around the implant. An improved peri-implant bone response could result in more favorable secondary stability during the application of orthodontic forces.

This review does not directly measure these biological mechanisms. It is limited to objective clinical criteria of stability, including the ISQ and Periotest values.

Limits You Should Know

The main obstacle is the volume of data. Five trials and 89 participants provide an insufficient basis for supporting clinical practice. The authors also note considerable heterogeneity regarding wavelength, irradiation protocols, energy parameters, the timing of force application, and methods for assessing stability.

The summary does not report a pooled effect estimate: this is a systematic review without a meta-analysis, and its results are presented narratively. Concerns regarding the concealment of allocation and blinding constitute an additional source of uncertainty. The authors explicitly conclude that these factors preclude the formulation of definitive clinical recommendations.

What This Means in Practice

The evidence points in a generally favorable direction but remains insufficient to establish a standardized protocol. The authors call for new, well-designed randomized trials using standardized radiation parameters and consistent evaluation methods before any evidence-based recommendations can be made.

For a patient undergoing orthodontic treatment, photobiomodulation remains a potential adjunct to be discussed with the practitioner, but it does not guarantee improved anchorage stability. It is not a substitute for either the placement technique or orthodontic follow-up.

Frequently Asked Questions

Does photobiomodulation improve the retention of orthodontic mini-screws?

Three of the five included trials reported an improvement in stability, while two found no difference. The authors conclude that the current data are insufficient to make a clinical recommendation.

What wavelengths were used in these tests?

The included studies used diode lasers ranging from 618 to 940 nm, with irradiation protocols and energy parameters that varied widely from one study to another.

Does this review apply to conventional dental implants?

No. It specifically concerns orthodontic anchor mini-implants, which differ from prosthetic dental implants in terms of size, mechanical load, and retention period.

Reference

Barreto-Santos J, Sousa-Santos P, Otão P. Effect of Diode Laser Photobiomodulation on the Stability of Orthodontic Mini-Implants: A Systematic Review of Randomized Clinical Trials. Journal of Clinical Medicine, 2026;15(14). PMID 42513542. Read on PubMed

This summary is provided for informational purposes only and does not constitute medical advice. Photobiomodulation is not a substitute for prescribed treatment. Consult a healthcare professional.