Methods of Assessing Lesion Depth and Severity with Near-IR Light

Dental caries (tooth decay) is one of the most prevalent chronic diseases worldwide and is the leading cause of tooth loss in the United States [1-3]. Tooth decay is the demineralization (loss of mineral) of enamel and dentin resulting from chemical reactions between the hard tissue and acids produced by oral bacteria in biofilms [4, 5]. A caries lesion is the effect the disease has on the tooth, which develops over a time period ranging weeks to years, and results in the formation of cavities, quite literally holes in teeth [8-10]. Early detection of primary and secondary dental decay, accompanied by appropriate nonsurgical treatment of the disease process, is the ideal method for practicing preventative dentistry. Clinicians’ lack the instrumentation to detect dental decay in its earliest stages with either radiographic imaging or visual tactile examination when the lesion process is reversible. This dissertation investigates the use of near-IR (NIR) light from 1300-1700-nm in wavelength for imaging the development of dental caries lesions. By developing and employing non-ionizing optical imaging technologies for the diagnosis of lesion depth and severity, we can avoid unnecessary surgical intervention (placement of restorations) and allow harmless routine monitoring of dental caries without radiation exposure. Additionally, these technologies are ideal for the production of portable hand-held instruments that can be used to detect decay without x-rays and can increase dental outreach globally