The Shining is a terrifying 1977 novel by Stephen King later adapted into a film. It features the Torrance family who experience the effects of supernatural entities with the mystical psychic power called 'The Shining', the ability to be a mind-reader and telepathic, and to visualise horrific sights of past and future. It is a chilling story, but is photobiomodulation ‘The Shining’ for oral health care?
Light therapy is all around us, both literally and metaphorically. Phototherapy involves being exposed to direct sunlight or controlled wavelength artificial light for the treatment of seasonally affective disorder and a variety of other conditions such as circadian rhythm sleep-wake disorders, cancers, neonatal jaundice and so on. Ultraviolet light is also used to treat dermatological conditions such as psoriasis, acne vulgaris and eczema among others. Transillumination is also used for diagnostic purposes and is excellent for diagnosing cracked teeth. With the advent of LED technology, mass market light therapy products have been developed with a whole variety of claims being made in relation to both health and wellness. Anti-ageing face masks are everywhere on the internet now, with the big electrical manufacturers leading the charge, both in terms of electricity and cost. Erik, the Phantom of the Opera would approve of some of the designs.
Photobiomodulation is the healthcare version of light therapy employing low-level laser therapy or LEDs. As a treatment, it is applied to a variety of body surfaces and is also known as cold therapy or red-light therapy. Photobiomodulation is therefore non-thermal and involves endogenous chromophores (molecules absorbing light) being energised which then undergo photophysical or photochemical reactions depending on the wavelength of light. For the scientific reader, the latter is the first law in photochemistry and is known as the Grotthuss-Draper law. Back in the clinical world, photobiomodulation is totally different to the use of high-powered energy beams in laser medicine where the purpose is to cut or destroy tissue.
So how is photobiomudulation proposed to exert a biological effect? The accepted theory is that light of wavelength 700-770nm has a low biochemical effect, whilst 810nm is optimal whereas around 950nm is needed to reach cutaneous sites and sub-dermal tissues. The primarily red, or near infrared light waves are absorbed by the chromophore cytochrome C oxidase (and other chromophores) which is a key component of the electron transport chain in mitochondria. This leads to larger production of adenosine triphosphate, the primary carrier of cellular energy, and is a metabolic ‘switch’ resulting in enhanced differentiation of stem cells, healing of damaged tissues through collagen production, cellular turnover, an increase in local circulation delivering additional nutrients and oxygen, and a reduction in oxidative stress of the tissue resulting in reduced inflammation through controlling the overproduction of pro-inflammatory molecules.
Where does dentistry and oral health fit in you might ask? In addition to carpal tunnel syndrome, fibromyalgia, rheumatological problems, low level laser therapy devices have been used to treat temperomandibular joint disorders, wound healing, oral mucositis in cancer patients, chronic periodontitis, dental implant healing, tissue regeneration, dentine hypersensitivity, recovery from wisdom tooth surgery and in my own sphere of clinical practise, reduction of orthodontic pain and to (hopefully) speed up orthodontic tooth movement. The proposed method of action for dental and oral healthcare is similar to that stated above; at the clinical level, the stimulation of cellular processes including collagen production and cell proliferation, ultimately upregulating the normal cellular turnover with accelerated tissue repair. Photobiomodulation in dentistry is proposed to reduce the effects of inflammation through minimising swelling, but also to intercept pain signal transmission through the sensory nerves which is beneficial in terms of respite, recovery and rehabilitation. Increasing osteoblastic activity following dental implant placement, dental extractions and orthognathic (jaw) surgery would be a bonus.
So far so good? Well, having been part of a Cochrane Review team evaluating a combination of non-surgical therapies in the acceleration of orthodontic treatment, we found orthodontic tooth movement was greater at the start of treatment, but slower in the later stages of treatment with the application of photobiomodulation. Whilst this finding is perplexing, I continue to keep an eye on the photobiomodulation research in dentistry and healthcare. Was this a chance finding? Our research team will repeat this review in due course and I am sure that there will be further evidence of photobiomodulation to synthesise in the years to come. At April 2025, 10K photobiomodulation publications are available with 2.7K of these being in dentistry alone showing the interest in this technology. However, the overall dental evidence is far from being conclusive at present.
I am sure photobiomodulation has potential to become a useful technological development for dentistry by harnessing the power of light to enhance healing, reduce pain, and improve treatment outcomes. As results are encouraging for conditions such as diabetic foot and venous ulcers, there is considerable promise in the treatment of chronic disease. Could it therefore be that photobiomodulation has more promise for chronic rather than acute conditions as one size rarely fits all? I will be keeping an eye on the research identifying the correct wavelength and intensity of light and the correct time of application for this treatment to be effective in oral healthcare.
Unlike The Shining, photobiomodulation is non-invasive and drug-free and whilst I am neither a mind-reader nor telepathic, the technology may have a positive future in dental and oral health care, particularly when used as an adjunct along with other therapies. In case you are interested, none of the photobiomodulation publications are by anyone called Torrance. Hopefully the mystical power of photobiomodulation in dentistry and oral healthcare will become clear in time.
Fellows and Members are welcome to contact me at dental@rcsed.ac.uk.