Dentistry has undergone substantial technological advancement, leading to the development of innovative diagnostic and therapeutic approaches. Biophotonics has emerged as an interdisciplinary field that integrates optical science with biological systems to facilitate the detection, monitoring and treatment of disease. Biophotonics technologies enable non-invasive imaging, molecular characterization and targeted therapeutic interventions at cellular and tissue levels. They provide significant advantages over conventional approaches by providing real-time information, enhanced precision and reduced patient morbidity (1,2). Traditionally, oral diseases such as caries, periodontitis, peri-implantitis, oral lichen planus and oral cancer have been viewed primarily as a function of bacterial plaque, the host immune response, and changes in the structure of the enamel, dentin, periodontium and mucosa (1). Endodontic assistance primarily involves a somewhat visual-tactile examination via visual-tactile means, radiographs and histopathology or tissue examination; however, these methods usually only identify the pathology after it has progressed to an advanced stage. Although therapeutic interventions may be effective, they often involve invasive procedures, radiation exposure or a long period of recovery once an individual has undergone treatment. Biophotonics achieves these goals, however, by using the properties of light-matter interactions to provide for real-time, specific molecular (diagnosing and/or treating) therapies without radiation (3).

Using various photochemical, photothermal, photomechanical and photoionization effects, rapid, sensitive, specific, low-cost and non-invasive methods have been developed. The development of biophotonics has its roots in Einstein's theory of photons and the first ruby laser in 1960, which was introduced into dentistry for early hard-tissue research in 1964(4). The challenge of thermal injury from CO₂ lasers was overcome by the introduction of short-pulsed infrared systems using Er:YAG (2.94 µm) and Er,Cr:YSGG (2.78 µm) laser configurations in the 1980s and 1990s, which allowed for very precise ablation and minimal collateral damage (5,6).

Recent advances in biophotonics have expanded the scope of dental diagnostics and therapeutics by enabling the improved visualization of tissue changes, enhanced microbial detection and more targeted treatment strategies. The synergistic association emerging between biophotonics and artificial intelligence (AI), quantum-enhanced imaging and advanced nanomaterials also enhances the likelihood that biophotonics will enable predictive, personalized and preventative oral healthcare solutions (7). While there have been some established advances in biophotonics, it continues to face a number of the same challenges that it has historically faced, e.g., limited penetration depth into highly scattering tissues, high costs associated with biophotonics devices, biophotonics device dependency and regulatory barriers regarding newly developed biophotonics devices (8). These deficiencies in future progress emphasize the need for increased research, standardization and translational efforts across the spectrum of oral healthcare, particularly in economically disadvantaged communities/areas where equal access is a priority.

The aim of the present narrative review was to provide a broad overview through a discussion of the core ideas, present-day practices, diagnosis and treatment methods, and the clinical relevance. The present review seeks to connect current science with future prospects in terms of progress in photonics-based precision oral healthcare that will be non-invasive, patient-centred and accessible to all.

A well-structured search of the existing literature was carried out across the PubMed, Scopus, Web of Science and Google Scholar databases. The search strategy used combinations of the following key words: Biophotonic dentistry, optical coherence tomography (OCT), Biophotonic laser therapy for periodontitis, photodynamic therapy (PDT) for oral cancer, Raman spectroscopy for dental caries, nanobioscience/mechanics in Biophotonic dentistry, AI in dental imaging, and nanomaterials (2000-2026). The search results included clinical trials/observational studies/molecular-level studies/reviews/market reports; editorials/non-peer-reviewed materials/irrelevant articles were excluded. The titles and abstracts were independently screened by two authors (ST. and SUN), followed by full-text assessments. Data extraction focused on biophotonic mechanisms, diagnostic applications, therapeutic modalities, clinical outcomes, emerging technologies and translational implications in dentistry.

In 1964, biophotonics made their way into the field of dentistry with hard tissue studies (4,6). Early CO₂ lasers caused the carbonization of hard tissues and were replaced by short-pulsed infrared systems (Er:YAG 2.94 µm, Er,Cr:YSGG 2.78 µm) in the 1980s and early 1990s due to the improved ability to perform precise ablative procedures (5,6).

The modern classification system categorizes biophotonics based on their methods of interaction (photochemical, photothermal, photomechanical and photoionization) and on their wavelength (visible=400-700 nm; near-infrared therapeutic window) (3).

Biophotonics can be further divided into three categories: Bioimaging, biosensing and photonic therapy, all of which are particularly relevant to both periodontal and restorative treatment in dentistry (1,2).

Biophotonic systems in dentistry employ light-based technologies, such as lasers and light-emitting diodes (LEDs) together with optical delivery and detection units to interact with oral tissues (3). Following exposure to biological tissues, light may undergo absorption, scattering, reflection, or fluorescence depending on the optical characteristics of the target site. These interactions produce various photonic effects, including photochemical, photothermal, photomechanical, and photoionization responses, which form the basis of several modern diagnostic and therapeutic dental applications (3,7).

As illustrated in Fig. 1, light-induced tissue interactions can trigger multiple cellular and molecular responses, including reactive oxygen species (ROS) formation, enhanced mitochondrial activity, fibroblast proliferation, collagen remodelling and antimicrobial effects. Collectively, these biological responses contribute to improved wound healing, periodontal regeneration, osseointegration, inflammation control and minimally invasive management of oral diseases Fig. 1 illustrates the fundamental principles of light-tissue interactions that underpin biophotonic applications in dentistry. When light from lasers or LEDs is transmitted to oral tissues by optical systems, it undergoes absorption, scattering, reflection, and fluorescence depending on composition of tissues and optical properties (3). These interactions lead to various biological effects, such as photochemical, photothermal, photomechanical and photobiomodulatory, which form basis of several diagnostic and therapeutic modalities (3,9). Clinically, these mechanisms help in antimicrobial activity, inflammation control, wound healing, periodontal regeneration and enhanced osseointegration. Fig. 1 highlights how a single optical stimulus can generate distinct biological responses depending on wavelength, energy density, and tissue characteristics, thereby enabling diverse applications across multiple dental specialties (9,10).

Clinically, dentistry is being transformed through biophotonics by bringing cutting-edge light science into an integrated system of detection, treatment and management of oral diseases (7). Imaging techniques, such as fluorescence imaging use autofluorescence to visualize early caries, demineralization and oral cancer so that these conditions can be managed with minimal invasiveness (11-13).

OCT provides ‘optical biopsy’ capabilities with a resolution between 5 and 15 µm to diagnose internal defects, cracks and bone loss (14). Molecular specificity is achieved using Raman spectroscopy to analyse biofilm and mineral content. Lasers (Er:YAG, diode, Nd:YAG, and CO₂) allow for precision ablation for soft tissue surgery and decontamination with haemostasis. PDT generates ROS to kill bacteria/viruses and to provide targeted anticancer therapy (15).

Photobiomodulation (PBM) enhances mitochondrial activity to accelerate healing, alleviate pain and facilitate osseointegration (9). The majority of these technologies will not be used in isolation; therefore, multimodal combinations will become the norm (e.g., fluorescence-guided PDT and OCT-monitored laser therapy), as they reflect care that is centred on the patient. A comparative overview of major biophotonic modalities, including their mechanisms and clinical implications, is presented in Table I. To contextualize the clinical value of the modalities summarized in Tables I, II provides a comparative analysis with traditional approaches commonly used in dentistry. This highlights potential of biophotonics to overcome key limitations of conventional methods.

The introduction of AI provides real-time decision support for data analysis, while deep learning enables the use of fluorescence/OCT/Raman spectra to estimate caries development and oral cancer outer limits with >95% specificity (7,39).

Multimodal AI will allow for capable explainable diagnostics in the oral health field (39). With the ability of AI to evaluate hyperspectral imaging modalities, risk categorization for periodontitis/peri-implantitis can be performed chair-side and thereby improved for high-risk patients. Data privacy and bias are challenges, but federated learning can help expedite the use of AI (39,40).

The application of quantum biophotonics allows for subshot-noise sensitivity and deeper penetration. The use of entangled photons may allow clinicians to achieve subcellular resolution in periodontal tissues or identify malignancies earlier than previously possible. NIR-II quantum dots allow for toxicity-free imaging of cm-scale bone regeneration via non-invasive imaging; thus, preclinical studies may support the use of optical biopsy as a diagnostic tool. Nanomaterials are expected to improve targeted therapies (41).

MXenes and upconverting nanoparticles can be used for PDT in deep pockets. Biomaterial scaffolds are biodegradable and promote regenerative processes, while allowing for monitoring (42). Graphene (hybrid) nanomaterials can also be used to create bioactive, light-activated (through antibacterial processes) implants. Intraoral SERS patch devices can be used to continuously monitor the presence of biomarkers in a patient, while also providing real-time monitoring. In summary, dentists can use combination platforms (OCT + Raman + photoacoustic), as well as other wearable tele-dentistry devices (43,44).

These align with the biophotonics roadmap, emphasizing label-free specificity and scalability, although costs and regulation remain hurdles.

Light is evolving from a diagnostic tool to a therapeutic precision instrument, necessitating a paradigm shift. Future research needs to prioritize the following: i) The application of non-invasive photonic biomarkers (i.e., salivary OCT/Raman assays) for use on the chair-side, risk assessments and the longitudinal tracking of the progression of chronic periodontal disease and the recurrence of oral cancer (44-46). ii) Integrating omics (photonic, metagenomic and AI) to map the virome-bacteriome present within periodontal lesions (1). iii) The development of novel theranostics (quantum dots, MXene nanoparticles and CRISPR-directed photonic activation for use in PDT and photobiomodulation) that allow for precision PDT/PBM application in periodontal pockets and/or peri-implant sites with the instant release of therapeutic agents (3,43). iv) Utilizing wearable intraoral sensors and teledentistry to provide personalized care in real-time, especially for underserved populations (44). v) Conducting standardized clinical trials and developing regulatory pathways for quantum and AI biophotonic devices to be translated into routine clinical practice expeditiously.

The first step towards the successful clinical development of biophotonic technologies is to demonstrate biological plausibility and validity of diagnosis. However, integration into practice does not depend only on technical performance, but also on clinician training, treatment protocols, reimbursement and regulation. Further analyses of cost-effectiveness are warranted to justify large-scale adoption (47).

Implementation in clinical practices continues to face various challenges. Chairside devices should be compatible with existing workflows so that the treatment time is not excessively increased. Moreover, these devices demand proper training so that the diagnostic output is well understood and interpreted by the practitioners. Furthermore, the high acquisition and maintenance costs of advanced modalities may restrict adoption, mainly in resource-constrained settings.

Additional challenges exist in rural and low-resource environments. The use of portable fluorescence-based diagnostic systems, teledentistry and simplified diagnostic procedures can make access easier and ensure the early detection of diseases of concern among vulnerable groups of individuals. In comparison with more advanced technologies, portable fluorescence devices may be a better option when it comes to application in low-resource environments, since they do not require too much investment in the infrastructure, and their use is relatively easy. The combination of portable fluorescence diagnostic systems with community dental health systems can perform early screening and referral actions in vulnerable groups of individuals (48).

Regulatory considerations are particularly critical for diagnostic systems assisted by AI and emerging multimodal imaging platforms, as they require rigorous validation of safety, reproducibility and clinical utility prior to routine use (40).

Educational preparedness represents an additional challenge. The use of biophotonic technologies is accompanied by the requirement of sufficient understanding of optical diagnostics, interpretation of images, as well as digital workflow. That is why it is reasonable to incorporate the educational program with these biophotonic technologies into dental studies. Moreover, variability in clinical protocols remains an issue, which requires standardization and multicenter validation. The effective utilization of biophotonic technologies requires competency in optical diagnostics, image interpretation and digital workflows, highlighting the need for integration into dental curricula and continuing professional education (49).

Technical advancements in biophotonics have expanded the understanding of diagnostics and treatment in dentistry beyond what is currently possible with standard techniques. Future enhancements using AI, quantum technology, intelligent nanomaterials and wearable devices will create precise preventive and person-specific treatment protocols for dental patients that will support their overall health and well-being. The roadmap provided in the present review addresses a number of the challenges that need to be overcome by the dental profession to accelerate the translation of biophotonics into clinical practice, improve the quality of care for patients and establish biophotonics as one of the cornerstones of dentistry in the 21st century. Additionally, the present review presents a timely, structured opportunity for dental researchers and practitioners to achieve this paradigm shift.