In this era of enhanced diagnostic digital technologies, clinicians desiring to provide the most up-to-date digital technology when diagnosing and treating their patients must be careful not to overlook opportunities to use well-proven evidence-based technologies. One such example of an adjunctive diagnostic tool that does not require additional digital support is fiber-optic transillumination (FOTI). Applications for fiber-optic transillumination include: its use as an adjunctive diagnostic aid for anterior and posterior interproximal caries and occlusal caries diagnosis; detection of calculus; evaluation of stained margins of composite resins; evaluation of cusp fractures and cracked teeth; as an exploration tool to illuminate endodontic access and root canal orifices within the pulp chamber of teeth during endodontic treatment; as a tool for improved evaluation of soft-tissue lesions; for evaluation of all-ceramic restorations to rule out any fractures before cementation; for clinical evaluation of fracture and craze lines in all-ceramic restorations and natural teeth; and for evaluation of depth of extrinsic staining to determine appropriate treatment recommendations.1
Fiber optics (optical fiber) refers to flexible, thin cylindrical fibers of high-optical-quality glass or plastic. The theory of fiber optics is based on a single optical fiber that consists of glass or plastic material with an outer cladding of a lower index of refraction material. Since the fiber core has a higher refractive index, light rays are reflected back into the core. This phenomenon is based on Snell’s Law and is called Total Internal Reflection (TIR). Individual fibers are grouped together to form a fiber optic bundle.1,2 These fibers can be as small as 0.01 mm in diameter for glass and 0.1 mm for plastic.2 Fiber optics have been used in dentistry for adjunctive illumination of other devices such as handpieces and ultrasonic scalers, as well as attached to magnifying loupes.
Dental and medical transillumination refers to light transmission through tissues of the body. Many remember experiencing transillumination of light as children during Halloween, when shining a flashlight through the mandible and soft tissues, thus creating an eerie red glowing appearance due to the red blood cells’ absorbing the other wavelengths of light. In fact, physicians use transillumination for diagnosis of hand tumors and for evaluation of sinuses and breasts.3-5 In dentistry, fiber-optic transillumination has been primarily associated with caries diagnosis. A bright light can illuminate the translucent tooth structure to reveal changes in tooth color, the presence of cracks and fractures, as well as other defects. Typically, the majority of carious lesions are visually accessible. Caries on occlusal and buccal/lingual surfaces account for almost 90% of caries in children and adolescents.6 Approximately 60% of caries occur in 20% of the population, and fewer than 5% of adults are caries-free.7 Caries has been identified as the single most common chronic disease of childhood. While caries is decreasing on interproximal surfaces, occlusal pit and fissue caries has shown a continued increase, yet the interproximal surfaces of the tooth are the least accessible to diagnose.
- See more at: https://www.dentalaegis.com/cced/2014/02/using-fiber-optic-transillumination-as-a-diagnostic-aid-in-dental-practice#sthash.6SVYrDi4.dpuf