Light Against Tooth Decay
Lasers in Dentistry – A Global Consensus
A new analysis by an international team of experts shows that laser technology—treated for years as a curiosity—may become one of the most important tools in the fight against dental caries. But before lasers find their way into every dental office, scientists temper expectations: research is ongoing, costs are high, and training takes time.
Dental caries is one of the few diseases where 21st-century medicine still moves at a rhythm familiar from the 1970s. The basic tools—fluoride, brushing, sealing—remain the same. On the one hand, caries is considered a trivial disease; on the other, it carries serious health consequences: chronic pain, inflammation, nutritional disorders, and in extreme cases even the risk of systemic complications. What’s more, traditional treatment comes with a paradox: to “repair” a tooth, you must first damage it.
This is precisely why technologies that strengthen tissues instead of removing them are generating so much interest. One of them is laser dentistry—a field developed for decades, but only now entering a stage in which it attracts not only researchers but also clinicians.
The Map of Lasers: From Liège to Wrocław
The latest Global Consensus Report developed by the World Federation for Laser Dentistry (WFLD) is the result of work by experts from eight countries - including Wroclaw Medical University. The document summarizes what we know about laser-assisted caries prevention and treatment.
Professor Kinga Grzech-Leśniak, Faculty of Medicine and Dentistry, Wroclaw Medical University, emphasizes that the role of WFLD goes beyond publishing reports:
“The World Federation for Laser Dentistry is a worldwide organization that plays a central role in advancing global education in laser-assisted dentistry. Through consensus reports, international congresses and academic programs such as EMDOLA, WFLD ensures that high-quality laser education remains accessible worldwide and fosters a new generation of well-trained professionals.”
Why Are We Still Losing the Fight Against Caries?
Dental caries is one of the most common chronic diseases in the world—affecting children, adults and the elderly. We have fluoride, sealants, better prevention, yet dental offices remain full of patients with new cavities. Traditional methods have limitations. They require consistency, patient cooperation, and high tolerance for pain and stress.
New technologies are not meant to replace toothbrushes and toothpaste, but to answer key questions: how to strengthen enamel, reduce bacterial load, preserve as much healthy tissue as possible, and improve healing. The goal is to break the cycle of “filling – larger filling – root canal – extraction.”
Lasers fit perfectly into the philosophy of minimally invasive dentistry: instead of drilling, they selectively remove altered tissue while leaving healthy structures untouched.
What Exactly Does a Laser Do Inside a Tooth?
In short, it uses light instead of mechanical cutting. But it is not a “flashlight for drilling.” Different types of lasers—Er:YAG, Er,Cr:YSGG, CO₂, Nd:YAG, diode—emit light at different wavelengths. This determines whether energy is absorbed primarily by water, hydroxyapatite (the mineral of enamel), bacterial pigments, or hemoglobin in soft tissues.
Erbium lasers (Er:YAG, Er,Cr:YSGG), strongly absorbed by water, allow selective removal of demineralized carious dentin. Water within the tissue heats rapidly, creating microscopic “explosions,” and diseased tissue is detached layer by layer. A cooling water-air spray prevents overheating. For the patient, this means fewer vibrations, less noise, and often reduced need for anesthesia.
In enamel, sub-ablative laser parameters cause melting and re-crystallization of the surface layer. Enamel becomes less porous, more resistant to acid dissolution, and more receptive to fluoride uptake. Studies cited in the report show that combining laser treatment with fluoridation can significantly increase enamel resistance to demineralization compared with fluoride alone.
The Stakes: Protecting the Pulp
Modern dentistry increasingly abandons the idea of “if it goes bad, we’ll do a root canal.” Preserving a tooth with a vital, well-vascularized pulp is key to longevity. Here, lasers begin to play a very concrete role.
Professor Samir Nammour, Faculty of Medicine, University of Liege, highlights one of the most promising areas:
“One aspect of laser-assisted caries management that already makes a tangible difference in daily clinical practice is laser-assisted direct pulp capping. Clinical outcomes obtained with laser-based protocols are significantly superior to those achieved with conventional (non-laser) techniques. By promoting more predictable pulpal healing and reducing postoperative complications, laser-assisted direct pulp capping enables clinicians to preserve tooth vitality and avoid unnecessary endodontic treatments, which is an essential factor for ensuring better long-term prognosis and tooth longevity.”
Direct pulp capping—when caries or trauma exposes living tissue and the dentist attempts to protect it rather than immediately perform root canal therapy—is one of the most sensitive moments in treatment. The WFLD report shows that properly selected laser protocols improve the chances of success: they kill bacteria, stimulate healing, and reduce inflammation.
Prof Samir Nammour, Department of Dental Sciences, Faculty of Medicine, University of Liège, Belgium
Prof Samir Nammour, Department of Dental Sciences, Faculty of Medicine, University of Liège, Belgium
What is crucial here is the shift in philosophy: the tooth is no longer a “construction material” replaceable with an implant but a living organ worth preserving.
Light That Reduces Pain and Fights Bacteria
Not all laser applications in dentistry involve “cutting.” Two rapidly developing fields are photobiomodulation (PBM) and photodynamic therapy (PDT).
- PBM uses low-energy light to modulate cellular processes: improve microcirculation, accelerate healing, and reduce pain. In the context of caries, this includes supporting remineralization of early lesions and reducing dentin hypersensitivity.
- PDT combines light with a photosensitizer that accumulates in the bacterial biofilm. Upon irradiation, reactive oxygen species are generated, selectively destroying bacteria. Studies cited in the report show that in deep caries—especially in children—PDT can reduce bacterial load and improve marginal seal of restorations while maintaining pulp vitality. It is not a replacement for drilling, but a valuable adjunct to minimally invasive strategies.
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Standardization
The WFLD report strongly emphasizes that this technology does not forgive sloppiness. It is not a device you “turn on and place on the tooth.” Key factors include wavelength selection, energy, pulse frequency, exposure time, and water cooling. Incorrect parameters may cause tissue overheating, enamel microcracks, or mechanical weakening of the tooth.
Professor Kinga Grzech-Leśniak states it clearly:
*“The three most important principles are, in my view, closely connected to understanding rather than merely using the laser.
First, a clinician must build a solid foundation in laser–tissue interaction…
Second, it is crucial to rely on validated, evidence-based parameters…
Third, hands-on training is indispensable… Structured, supervised practice gives beginners the confidence and precision they need to work safely.”*
This is why the report devotes so much space to protocols, recommended energy ranges for enamel and dentin, and differences between surface preparation and actual cavity excavation. These details may not make for spectacular marketing—but they are critical for safety.
Prof Kinga Grzech-Leśniak, Department of Integrated Dentistry, Faculty of Dentistry, Wroclaw Medical University, Poland and Prof Samir Nammour, Department of Dental Sciences, Faculty of Medicine, University of Liège, Belgium
Prof Kinga Grzech-Leśniak, Department of Integrated Dentistry, Faculty of Dentistry, Wroclaw Medical University, Poland and Prof Samir Nammour, Department of Dental Sciences, Faculty of Medicine, University of Liège, Belgium
Professor Grzech-Leśniak also stresses that laser education cannot be reduced to “operating a device”:
“For clinicians who wish to go beyond the basics, I warmly encourage joining the European Master Degree in Oral Laser Applications, EMDOLA… EMDOLA teaches clinicians how to think and plan treatments based on tissue structure, absorption mechanisms and individualized parameter selection—not simply how to operate a device.”
This is an important shift—from “which button do I press?” to “how will this tissue respond to this wavelength?”
Healthy Scepticism
Many dentists react with scepticism when they hear the word “laser.” Some remember early, expensive, impractical devices. Others recall exaggerated promises from manufacturers, and still others point to the fact that much evidence is still in vitro or short-term.
Professor Nammour notes that part of the misunderstanding stems from the word “laser” itself:
“Scepticism toward dental lasers is often rooted in a misunderstanding: ‘LASER’ is a broad term… Each wavelength has its own specific clinical indications… For this reason, lasers are not multifunctional instruments that can be used for every type of treatment.”
It is a bit like referring to every medication simply as a “pill” and expecting one “pill” to cure everything from headaches to diabetes.
He also has a clear message for those concerned about gaps in clinical evidence:
“To practitioners who remain hesitant… my key message is to seek accurate, evidence-based information… As long-term clinical studies continue to develop, those who invest in proper education today will be optimally positioned to integrate this powerful technology into modern minimally invasive dentistry.”
The report does not pretend that we know everything. It explicitly highlights weak points: insufficient long-term clinical trials, limited protocol standardization, high equipment costs. But it also presents areas where benefits are well documented: increased enamel resistance to acids, improved fluoride retention, selective caries removal, enhanced healing, and treatment of hypersensitivity.
Technology vs. Reality in the Dental Office
Many clinicians ask a simple but critical question: even if lasers work, how do we introduce them into practice when high-end devices cost as much as a small car—and additional costs include tips, service, and training?
Professor Grzech-Leśniak proposes a very pragmatic model:
“A realistic pathway toward making laser dentistry widely accessible begins with introducing clinicians to simpler and inherently safer modalities, such as aPDT and PBM… Once these fundamentals are established, clinicians can gradually progress to high-energy systems…”
She also stresses the importance of choosing the right starting point:
“Alternatively, beginners can approach laser dentistry by starting with simple soft-tissue procedures… My key recommendation is to start with the procedures you genuinely enjoy.”
A further element is equipment sharing in multi-specialty clinics, dental centers, and universities. Instead of buying “exclusive lasers,” institutions can adopt shared-use models where one device serves several clinicians.
The implementation model outlined by the WFLD report and expert commentary can be summarized as:
– begin with inexpensive, low-energy techniques (PBM, aPDT),
– progress to diode lasers and soft-tissue procedures,
– only then invest in erbium systems for hard tissues.
Prof Kinga Grzech-Leśniak, Department of Integrated Dentistry, Faculty of Dentistry, Wroclaw Medical University, Poland
Prof Kinga Grzech-Leśniak, Department of Integrated Dentistry, Faculty of Dentistry, Wroclaw Medical University, Poland
As Professor Grzech-Leśniak concludes:
“Through a combination of accessible entry-level techniques, passion-driven learning, structured education and collaborative access to equipment, laser dentistry can become both widely available and responsibly integrated into everyday practice.”
Less Drilling, More Biology
The WFLD global consensus is not a manifesto insisting that “everyone should buy a laser tomorrow.” Rather, it is a roadmap: it shows where the technology is mature enough for responsible implementation and where more data are needed.
One thing seems clear: dentistry is moving toward conscious minimalism. Less aggression toward tissues, more understanding of their biology. Less of the simple “cut and fill,” more strengthening, remineralization, and preservation of vitality.
Lasers—used with humility and knowledge—fit this shift perfectly. They are not futuristic gadgets but tools that may allow future generations to associate the dental chair not with a drill, but with a touch of light.
D. Sikora
FAQ: Laser-Assisted Caries Prevention and Treatment
What makes laser-assisted caries removal different from conventional drilling?
Laser-assisted caries removal is based on selective ablation. Because demineralized dentin and enamel contain more water and exhibit different optical properties, erbium lasers (Er:YAG and Er,Cr:YSGG) preferentially target diseased tissue while preserving adjacent healthy structures. This aligns with the principles of minimally invasive dentistry and reduces the mechanical and thermal stress associated with rotary instruments.
Can lasers actually increase enamel resistance to acid attacks?
Yes. Subablative laser irradiation can induce superficial melting and recrystallization of enamel, reducing porosity and enhancing resistance to demineralization. Evidence also shows improved fluoride uptake and retention when laser treatment is combined with topical fluorides, resulting in a synergistic preventive effect.
How do lasers support remineralization of early carious lesions?
Both erbium lasers and photobiomodulation (PBM) therapy have been shown to facilitate remineralization. Laser-modified enamel exhibits increased surface energy and improved receptivity to agents such as CPP–ACP or fluoride gels, leading to higher microhardness values and shallower lesion depths. PBM additionally stimulates cellular responses within the pulp–dentin complex that support biological repair.
What role do lasers play in improving restorative outcomes?
Laser conditioning can enhance adhesion by creating a micro-roughened surface, modifying surface chemistry, and removing the smear layer. In fissure sealing, laser-prepared enamel exhibits reduced microleakage and improved sealant retention. In restorative dentistry, erbium laser preparation of dentin improves adhesive penetration, particularly when combined with conventional etching.
Are lasers effective for managing dentin hypersensitivity?
Yes. High-power lasers (e.g., Nd:YAG, Er:YAG, Er,Cr:YSGG) provide photothermal sealing of dentinal tubules, while low-level lasers promote neural modulation and anti-inflammatory effects through PBM. Both approaches reduce hypersensitivity, and combination protocols with fluoride or desensitizing agents show enhanced and longer-lasting results.
Is photodynamic therapy (PDT) a viable adjunct in caries management?
PDT demonstrates significant antimicrobial activity against cariogenic bacteria, including Streptococcus mutans and Lactobacillus species. When used alongside selective caries removal, PDT can improve microbial control and support restoration longevity. However, protocols vary widely, and PDT is recommended as an adjunct—not a replacement—for conventional treatment.
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About the journal:
(Dent Med Probl) is an international, peer-reviewed, open access journal covering aspects of oral sciences and general medicine, published bimonthly by Wroclaw Medical University.
The journal is a leading dental scholarly journal in Eastern Europe founded in 1960 from the initiative of Prof. Tadeusz Owiński. It was originally called "Wrocławski Biuletyn Stomatologiczny". In 1965, the journal was renamed to "Wrocławska Stomatologia", and then the name was changed to "Dental and Medical Problems" in 2002.
Dental and Medical Problems is the first dentistry-profile scholarly journal in Poland and Eastern Europe in general which received a Journal Impact Factor (JIF) in the 2023 release of the Journal Citation Reports™. The current JIF is 3.9.
This material is based on the article:
Samir Nammour, Aldo Brugnera Junior, Toni Zeinoun, Jacek Matys, Sonia Bordin-Aykroyd, Paul Nahas, Marwan El Mobadder, Sajee Sattayut, Darinca Carmen Todea, Akira Aoki, Kinga Grzech-Leśniak
Dental and Medical Problems
Web. A. Maj
Photo: freepik.com, graphics from original article
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