Accelerated orthodontics using photobiomodulation

Dr. Bill Kottemann examines the process of photobiomodulation to accelerate orthodontic tooth movement

Introduction

Opinion among orthodontists on the topic of acceleration can vary greatly based on the hands-on user experience and case types. Today, there are two basic options in patient handheld devices: vibration and light therapy. Light therapy uses a process called photobiomodulation, which is the technology behind OrthoPulse® made by Biolux Research. This article will examine the process of photobiomodulation, and its use in acceleration, its safety, and considerations when choosing which patients will benefit from this cutting-edge technology.

Light energy and the application in orthodontics

A simple example of light energy is photosynthesis — the process of chemical energy fueling plant organisms’ activity such as growth. Human cells, particularly mitochondria, also have the ability to absorb photons from light to enhance cellular activity.

This general philosophy correlates to the light energy conversions of photobiomodulation: “The application of therapeutic light in the near-infrared wavelength (NIR) range (600 nm-1000 nm) generated by using low-energy laser or light-emitting diode (LED).” Photobiomodulation has been observed to increase mitochondrial metabolism.¹ This process can be used in orthodontics to help benefit the biological effects in stressed tissues as teeth are moved.

Biological explanation of photo-biomodulation

Mitochondrial enzymes can absorb photons from light and increase the production of ATP energy, allowing the tissues to metabolize normally. ATP production has been shown to be upregulated twofold by infrared light, also known as photobiomodulation.²

During the tooth movement phase, higher ATP production is enhanced, leading to cells “turning over” more efficiently. Light-accelerated orthodontic therapy shows promise in producing a noninvasive stimulation of the dentoalveolar complex with a potential impact on ATP production by mitochondrial cells. The assumption is that an increase in ATP at a localized site will induce cells to undergo remodeling — stimulating both apposition and resorption to enhance tooth movement.³ Light-accelerating orthodontics (LAO) may also be functioning through increased vascular activity, which would also contribute to the rapid turnover of the bone. A number of clinical case studies have suggested an enhanced impact by LAO, increased velocity of canine movement, decreased pain, and a significantly higher acceleration of retraction of treated canines.⁴

Figure 1: Stressed cells (left) and initiation of photobiomodulation (right) producing the increase in energy ATP

Over 80 years of research in photobiomodulation

More than 5,000 articles have been published on the effects of photobiomodulation. The German biochemist, Otto Warburg (1883-1970), was awarded the Nobel Prize for discovering cytochrome c oxidase (CCO), the terminal enzyme in the mitochondrial oxidative respiration chain. In his research, he found that applying specific frequencies of light to mitochondria stimulated their activity. Warburg also demonstrated that carbon monoxide inhibited CCO function and could be displaced by a flash of light. Displacing carbon monoxide allows oxygen to bind again and resume CCO function and respiration. Photobiomodulation activates cytochrome c oxidase and increases mitochondrial electron transport, which leads to increased ATP production. Confirmation that cytochrome c oxidase is the photoacceptor in the red to near-infrared (NIR) spectral range can be found in the article “Photobiomodulation accelerates orthodontic alignment in the early phase of treatment.”⁴

Figure 2: Light spectrum chart showing photobiomodulation at 850 nm, well within the safe range between 600 nm and 1000 nm

OrthoPulse® safety

The product that utilizes photobiomodulation, OrthoPulse®, is a U.S. FDA-cleared Class II medical device for patients receiving fixed appliance or aligner treatment. Regulatory approvals have also been received in the European Union, Canada, Australia as well as other countries. Biolux Research continues to sponsor and support research at the Forsyth Institute, University of Southern California, Kyung Hee University, European University College, United Arab Emirates University, University of Sydney, and Tufts University.

The device is designed to be used by patients on a daily basis for 5 minutes in each arch, either at home or while traveling. The clinical evidence acquired to date shows a significant reduction in treatment time for patients undergoing orthodontic treatment.⁴

Light therapy device

The intraoral device is integrated with light-emitting diode arrays, which emit a continuous 850 nm near-infrared light toward the buccal alveolar mucosa to promote bone remodeling. The energy density is 19.5 J/cm2 when used for 5 minutes per arch daily.

Application of light in dentistry has been clinically proven to be safe without adverse events such as root resorption, pathologic tooth mobility, and gingival recession. For OrthoPulse, the power output is low, and treatment occurs at temperatures below 43°C.⁵

Since 2003, there have been over 30 OrthoPulse clinical trials as well as in vivo and in vitro studies. In vivo research findings show a 3.3-fold faster rate of tooth movement⁶ and 80% less root resorption in animals treated with 620 nm light.⁷

For both aligner and fixed appliance patients, adding light-accelerated orthodontics using photobiomodulation at 850 nm wavelength facilitates bone remodeling on a molecular level without adverse effects. The shorter the wavelength, the more it is absorbed in soft tissue; and the longer the wavelength, the deeper the penetration through soft tissue, and hence into the bone. The 850 nm wavelength is considered within the near-infrared spectrum.

Photobiomodulation use in the orthodontic practice

Biolux Research has a general guideline that once patients start orthodontic treatment, they should begin OrthoPulse immediately using 5 minutes per arch daily.

If an Invisalign® case involves challenging movements such as a large translation in opening/closing spaces (i.e., molar distalization or extraction), acceleration with photobiomodulation can help keep the case on track and increase predictability.

In general, on a 7-day Invisalign aligner case, patients change their aligners every 5 days using OrthoPulse — a 20% reduction in treatment on an already shortened case with a 7-day versus 14-day change rate. However, it is very important to review the case when the challenging movements and IPR are staged. If it’s simple anterior crowding, then a 3.5-day change rate will most likely work well. If a series of aligners is distalizing the posterior segment, adjust to a 5-day change rate. For all Invisalign cases, I have noted a 20% refinement rate in my practice. Adding acceleration with OrthoPulse on these cases has not increased the low refinement rate percentage.

Regarding costs, our practice adds $500 to the case fee for patients who want to accelerate their treatment. This is a loss leader on paper due to the cost of the unit. The reduction in treatment time and number of appointments, plus increasing predictability and generating very happy patients with a positive experience, makes up for the $300-plus cost differential. The shorter treatment time allows the practice to open schedules for additional patients. Patients keep their payments on the same schedule as if they had not accelerated their treatment time. For example, a normally 18-month case would be reduced to 12 months or less through photobiomodulation. The payment schedule remains at 18 months, plus $500 for the unit.

Case studies

The following two cases are part of a study that I am involved with regarding OrthoPulse and aligner treatment, analyzing the results of 5- and 3.5-day change rates.

Case 1: Class I deep bite with 5-day change rate with Invisalign and OrthoPulse

Peter, a 26-year-old male, presented with Class I occlusion. He was congenitally missing all four second bicuspids. X-rays show tipping of teeth into edentulous sites and a deep overbite.

The treatment plan would upright posterior teeth to restore the missing second bicuspids with implants. Peter was put in the part of the study that mandated 5-day aligner changes.

Figure 3: Initial records for Peter

In addition, I added these instructions to Peter’s ClinCheck setup:

“Please leave 7s in crossbite. Make upper pontic spaces both 8.0 mm. Make both lower pontic spaces 8.4 mm. Reduce gingival margin height on pontics to make the pontics the same length as the molars and bicuspids. IPR lower 3,2|,|2,3 to account for Bolton discrepancy.

Upper arch over-corrections:

• Rotate 2|mesial-out 5 degrees and Rotate |1 mesial-in 5 degrees

Lower arch over-corrections:

• Rotate 2| mesial-out 5 degrees and Rotate 1| mesial-out 5 degrees

Thank you.”

Peter’s case was completed in 4 months with 19 aligners. With photobiomodulation, Peter changed the aligners every 5 days. Retainers were fabricated at stage 17, and everything tracked very well. By integrating Invisalign with OrthoPulse into his treatment plan, not only was the long-term stability of his implants increased by the segmental uprighting of the posterior teeth, but also his overall function was greatly improved in less time.

Figure 4: Initial records (left) versus final records with implant (right)

Figure 5: Final X-rays

Figure 6: A side-by-side comparison on final ClinCheck images and actual results

Case 2: Mild crowding/diastema correction with a 3.5-day change rate with Invisalign and OrthoPulse

Jessica, a 34-year-old female, came into our office with Class I occlusion and enamel erosion of upper anterior teeth. She also presented with maxillary spacing, a 2 mm diastema, and mandibular crowding with mild bimaxillary protrusion.

The treatment plan included intruding and retracting the upper and lower arches, and IPR the lower arch to address the Bolton discrepancy. In addition, we wanted to intrude the upper and lower incisors to allow for upper incisor crowns. As part of the clinical study, Jessica was put into the 3.5-day aligner change group. The patient was instructed to change aligners on 2 specific days of the week at 3- and 4-day intervals, respectively — for example, changing aligners every Tuesday and Friday. This makes it very easy for the patient to remember and stay compliant.

Figure 7: Initial records for Jessica

In addition, I added these instructions to Jessica’s ClinCheck setup:

“Upper 1|1 to be restored. Leave upper 1| shorter than |1. Set overbite to 0.5 mm at |1 to allow for future crowns. OK to leave spaces mesial and distal to upper 2|,|2 if Bolton discrepancy.

Upper arch over-corrections:

• Rotate |2 mesial-in.

Lower arch over-corrections:

• Move 2|,|2 lingual, Rotate 1|,|1 mesial-out, and Move |3 labial

Thank you.”

Jessica finished her treatment in 9 weeks with 18 upper and lower aligners changed every 3.5 days with acceleration through photobiomodulation. Her upper and lower Invisalign retainers were made at stage 17. We have also referred her for crowns on the upper incisors. I was pleased with the results of the 3.5-day change rate, and Jessica told us that she was thrilled. Reducing treatment time to 9 weeks versus the almost 5 months it would have taken for treatment, if we had not used photobiomodulation, was remarkable. The convenience for the patient makes it a win/win situation for her and our office.

Figure 8: A side-by-side comparison initial versus final records

Figure 9: Final X-rays[

Figure 10: Final treatment records versus ClinCheck

Conclusion

Photobiomodulation in orthodontics is an exciting next frontier for our profession. I am pleased with the results I am seeing in my practice and the real efficiency and predictability. I feel comfortable recommending OrthoPulse® to my patients with the expectation it will reduce their treatment time by half. It can definitely generate a new generation of patients who want their treatment done more quickly and can differentiate my practice in a competitive market. This technology and its use of the photobiomodulation process is based on solid science.