SBIR Phase I: Brillouin Microscopy for Early Detection of Dental Caries

The broader/commercial impact of this SBIR Phase I project will apply Brillouin spectroscopy (an optical method of measuring the speed of sound in a sample) to the early detection of dental caries (cavities). While Brillouin spectroscopy has been used to study other materials, it has not been used before to study caries in the dental enamel. However, initial data and theoretical models suggest that the technology can effectively detect early carious lesions. Once developed, this method will be capable of detecting caries in teeth early enough that remineralization treatments can be effectively used to reverse caries progression, thus sharply reducing the need for drilling, cavity filling, root canals, and implants. Upon widespread commercial adoption, this concept would fundamentally change dental practice, and allow it to focus on prevention instead of intervention. This will improve the patient experience by reducing the need for painful or uncomfortable dental procedures, thereby increasing patient satisfaction and compliance with bi-annual dental exams. The total addressable market for these systems and associated consumables is estimated to be worth nearly $2 billion per year in the United States, and around $5 billion per year worldwide. The project proposes Brillouin spectroscopy as a new modality of detecting early caries. The advantage of Brillouin spectroscopy over existing methodology is that it directly detects the enamel softening associated with demineralization in early caries. This patent-pending method is theorized to be more robust to confounding factors such as stains, calculus, and plaques, while maintaining the significant advantages of optical detection: it is non-ionizing, non-damaging, and non-contact, allowing for flexible detection geometry. The overall objective of this proposal is to validate Brillouin spectroscopy as a new, cost-effective, reliable diagnostic method of positively identifying carious lesions at an early stage. To achieve this goal, the project proposes two steps: First, a controlled, in vitro characterization of the sensitivity of Brillouin spectroscopy to early caries will be conducted. The caries will be induced incrementally by a pH-cycling protocol to create physiologically realistic demineralization. Second, the influence of common and potential confounding factors, such as staining, hydration, and incident angle of the light will be assessed. The expectation is that the resulting data will conclusively support the further development of Brillouin spectroscopy for early caries detection. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.