The Role of the Near-Infrared Light-Emitting Diode in Dental and Oral Surgery
Erin Morency1, Manuel Dujovny2*, Onyekachi Ibe3, Pablo Sosa4, Fabian Cremaschi4, Lori Burkow-Heikkinen5
1School of Nursing, Oakland University, Human Health Building, Rochester MI, USA.
2Department of Neurosurgery, Wayne State University, Detroit MI, USA.
3College of Engineering & Information Science, DeVry University, Southfield, MI, USA.
4Department of Neuroscience, Clinical and Surgical Neurology, School of Medicine, National University of Cuyo, Centro Universidad,
5American College of Sports Medicine, Indianapolis, IN, USA
Examples of common devices that use near infrared radiation are night vision goggles, digital cameras, and remote controls. New devices available also include arms that can attach to a dentist chair and arc over the patient’s mouth, illuminating the oral cavity. Today, near infrared has gone beyond industrial use and is used in a variety of clinical and medical applications such as oxygen spectroscopy, imaging, photodynamic therapy, optic thermography, photobiomodulation, remote monitoring, thermal radiation (heat) and other optical devices.
The NIR-LED equipment is about the size of older model cellular telephones. The unit connects via a cord to the a standard electrical outlet, and the device comes with a specific adaptor. Some models can function with the use of single use or rechargeable AA or AAA batteries as well. The device has been miniaturized and battery powered, also now available in the size of a standard electric toothbrush. This reduced size configuration has allowed it to be used for root canal sterilization and dental curing. The significant reduction in size has facilitated the treatment of the oral mucosa damage which often occurs in preparation of treatment for bone marrow transplantation.[3,4] In this article we will discuss the physiopathology of wound healing and inflammation after tooth extraction.
Oral health care problems are prominent in all age groups. In the US children aged 5-17 are five times more likely to have dental caries than asthma. It is the most common chronic disease in this age group. In many cases tooth extraction is recommended due to the extensive decay. Extraction is also necessary to create space for orthodontic treatment. Post extraction therapy usually involves an ice pack being applied to the area of the face, as well as the prescription of pain medications including anti-inflammatory and narcotics. The rate of oral diseases increases with age; these diseases include gingivitis, root inflammation/infection, and dental caries. Along with these diseases the elderly are having more dental implants as technology improves. In this review we focus on a technique which we believe has been underutilized; the near infrared Light Emitting Diode gallium arsenide. We recognize the unique capabilities of this wavelength to accelerate wound healing and decrease inflammation of the surrounding tissues. We will address the physiological state of the sites treated by dental extraction.
Materials and Methods
Wound healing ends with completion of wound repair and tissue regeneration. The main reparative cell is the fibroblast. Whelan et al. compared the use of hyperbaric oxygen with NIRLED and found that fibroblast numbers increased 140-200% as well an increase of 155-171% in epithelial cells, similar to those of the oral mucosa. Fibroblasts are able to increase in number and activity with the use of near infrared light, because of the increase in mediators like transforming growth factor-beta and platelet-derived growth factor.[2,10,15] NIR treatments of 3 J/cm(2) resulted in increased fibroblast cell growth without affecting procollagen synthesis Another integral component of tissue regeneration is stem cells; which have been observed to increase in number and activity via near infrared stimulation.[17-18].
Collagen is another important scaffold needed for wound healing, types I and III being prevalent. In a diabetic rat model, diabetic rats treated with low level laser therapy had collagen density and deposition more similar to those of the control, non-diabetic rats, than the diabetic rats who had not been treated.
Metalloproteases are responsible for the remodeling of collagen and the composition of the extracellular matrix due to interaction with fibroblast growth factor. These enzymes create the balance of synthesis and degradation of appropriate molecules for effective regeneration for wound healing and tissue repair, and they can be improved by near infrared light.[20-21] Modulation of all of the wound healing and tissue repair and inflammation processes are accelerated by NIR LED.
Many growth factors play an important role in the tissue regeneration process. Epidermal growth factor and transforming growth factor beta are necessary for cell proliferation and differentiation. Platelet derived growth factor, fibroblast growth factor, and vascular endothelial growth factor are both involved in the process of angiogenesis; while keratinocyte growth factor helps with epitheliazation. In our observations, the NIR-LED GaAs decreased inflammation, while also accelerated wound healing and tissue repair.
NIR therapy increases osteoclast formation and bone regeneration. Low level laser therapy has been shown to potentially lower tooth relapse, with the thought being that bone formation occurred more efficiently because of greater osteoclast numbers. El Bialy et al observed increased levels of mandibular growth stimulation on rats treated with NIR-LED over those that were treated with low level lasers . The use of NIR light can help stimulate osteoblasts while minimizing swelling .
The development of implant surgery has created a different need for wound healing; more efficient wound healing can lead to increases in implant success rates. Prostaglandin E2 values had a negative correlation with the stability of implants, leading researchers to find a positive correlation between NIRLED therapy and the osseointegration process. Low level laser therapy promoted improved bone healing on rabbits who received titanium implants on their tibia, modeling dental implants, and were treated with a 830-nm laser for seven sessions at 48-h intervals. They postulated that the difference in the hydroxyapatite of calcium value was the reason for the difference. Similarly, Brawn and Kwong-Hing observed accelerated bone healing after a socket graft with hydroxyapatite and 21 days of phototherapy treatment. When using an 830nm laser at 20J/cm(2) Gomes et al found that low level laser therapy improved peri-implant bone repair by increasing stability, bone-implant contact, and bone regeneration. Faria et al observed increased bone formation after implantation of mandibular bone defects in mongrel dogs with the aid of photosensitivity drugs treated by NIR LED .
The mouth is a unique environment, significantly colonized by bacteria, increasing the risk for extended inflammation. Common
Pain occurs soon after dental trauma including extraction. Current methods of pain control include ice packs, moist heat, anti-inflammatories and narcotics. Barretto et al observed anti- nociceptive responses after stimulation with NIR low level laser therapy. Vinck et al completed a study using a NIRLED and concluded that the effects on pain were most likely a result of localized effects of the ability of the nerves to conduct signals. After removal of a tooth, the dentist commonly recommends an ice pack to apply to the area. It is the experience of one author that NIR-LED application two to three times a day post removal, at ten minutes per session, for the next seven days, resulted in a significant reduction of pain and inflammation as well as increased gumtition of the socket of the tooth. The pain was relieved without the need of narcotics or other palliative therapies (ice packs). Esper et al. observed a greater reduction of pain sensitivity and orthodontic tooth movement with the use of a NIR-LED(640 nm with 40 nm full-bandwidth at half maximum, 4J/cm (2), 0.10 W, 70 s) compared to a control group. NIR low level laser therapy after supernumerary tooth surgical removal and frenectomy resulted in lower levels of pain. Whelan et al reported the use of NIR-LED decreased pain in children with oral mucositis by 47 percent. After surgical removal of impacted third molars, Batinjan et al used near infrared low level laser therapy to treat wound swelling and temperature changes. The results showed that both swelling and temperature in the wound area were decreased.  A double blind study showed that there was a decrease in pain and discomfort after dental flap surgery with the use of 660 nm near infrared laser irradiation (biomodulation).
Both light emitting diodes and low level lasers produce the same effects via NIR stimulation of tissue. As reported, the effects
Cite this article: Dujovny M. The Role of the Near-Infrared Light-Emitting Diode in Dental and Oral Surgery. J J Otolaryn. 2015, 1(4): 018.