Lighting Up Orthodontics: How Photobiomodulation Could Transform Tooth Movement

A non-invasive light-based therapy may help ease pain, speed up treatment, and protect roots during orthodontic care but important questions remain.

A New Twist in Orthodontic Treatment

Orthodontic treatment has come a long way from the days of simple metal braces. Today, researchers are exploring innovative methods to make treatment faster, safer, and more comfortable. One promising candidate is photobiomodulation therapy (PBMT) a low-intensity light therapy already used in various areas of medicine and dentistry.

PBMT uses red and near-infrared light to stimulate biological processes inside cells. Clinicians have long known that it can help reduce pain, ease inflammation, and speed tissue healing. But could PBMT also support orthodontic tooth movement (OTM)? And if so, how does it work?

A recent review published in the Journal of Zhejiang University – Science B takes a deep dive into these questions, examining the biological mechanisms behind PBMT and its potential role in orthodontics.

How Light Influences Cells and Tissues

PBMT may look simple on the surface shining low-level light onto tissues but the underlying biology is surprisingly sophisticated.

When red or near-infrared light enters cells, it interacts with key cellular components such as cytochrome c oxidase (CCO) inside mitochondria. This interaction triggers:

• Increased ATP production, boosting cellular energy

• Short bursts of reactive oxygen species (ROS) that act as signaling molecules

• Release of nitric oxide (NO), improving blood flow

• Activation of pathways that support cell survival, repair, and regeneration

  
  

These effects help tissues respond better to stress including the mechanical forces involved in moving teeth.

What Researchers Did

The authors reviewed decades of experimental and clinical work covering:

• PBMT effects on periodontal ligament (PDL) cells, bone cells, blood vessels, nerves, and immune responses

• Animal and human studies evaluating pain, inflammation, tooth movement rate, and root resorption

• Technical challenges such as the actual amount of light energy that reaches the tooth root

Their goal was to evaluate whether PBMT can meaningfully assist orthodontic treatment and what needs to be solved before it becomes a mainstream tool.

What the Evidence Shows

1. Pain Relief

Multiple studies show that PBMT can reduce orthodontic pain, especially during early stages of treatment when force is first applied. Patients often report lower discomfort compared to control groups.

2. Faster Tooth Movement

PBMT appears to increase the rate of tooth movement by stimulating bone remodeling the balanced process of bone resorption and formation that allows teeth to shift within the jaw.

Some studies report 24–30% faster movement compared to orthodontic force alone.

3. Improved Tissue Healing

PBMT may support healthier periodontal tissues by:

• Increasing blood vessel formation (angiogenesis)

• Stimulating fibroblast and stem cell activity

• Enhancing collagen production

These effects may help maintain tissue integrity during orthodontic stress.

4. Potential Protection Against Root Resorption

Orthodontically induced inflammatory root resorption (OIIRR) is a common concern. PBMT may help by:

• Modulating inflammatory pathways

• Supporting cementoblast (root-surface cell) survival and differentiation

• Regulating osteoclast and osteoblast activity

However, evidence remains moderate, and results vary across studies.

The Big Challenges

Despite encouraging findings, PBMT has not gained widespread adoption in orthodontics — and the review explains why.

1. How Much Light Actually Reaches the Tooth Root?

Periodontal tissues absorb and scatter light, meaning only a fraction reaches deep targets. The real delivered energy dose remains unknown, making it hard to standardize treatment.

2. Uncertain Penetration Depth

Different wavelengths travel differently through soft tissue, bone, and tooth structures. Without precise data, clinicians cannot reliably tailor PBMT for orthodontic use.

3. No Consensus on Optimal Parameters

Many variables affect PBMT outcomes:

• Wavelength

• Power and energy density

• Exposure time

• Beam size

• Treatment frequency

Current studies use highly inconsistent settings, making comparisons difficult.

Where Do We Go From Here?

The review concludes that PBMT is biologically promising and has demonstrated benefits in pain control, accelerated movement, and tissue repair. However, key scientific gaps must be addressed before clinicians can apply it confidently.

Future research should:

• Measure actual energy reaching periodontal and root surfaces

• Determine optimal wavelength-energy-timing combinations

• Explore long-term safety and consistency across different patient groups

• Clarify cellular mechanisms linked specifically to orthodontic forces

With clearer protocols and validated parameters, PBMT could become a valuable complementary tool in orthodontics offering faster, more comfortable treatment with fewer side effects.

Reference

Yong J, Gröger S, von Bremen J, et al. Photobiomodulation therapy assisted orthodontic tooth movement: potential implications, challenges, and new perspectives. Journal of Zhejiang University – Science B. 2023;24(11):957–973.

DOI: https://doi.org/10.1631/jzus.B2200706