Indocyanine-green-assisted near-infrared dental imaging - the feasibility of in vivo imaging and the optimization of imaging conditions

Abstract

X-ray-based imaging, including computed tomography, plays a crucial role in the diagnosis and surgery of impacted teeth that affects over 25% of the human population. But the greatest disadvantage of this technique is ionizing radiation risk to the patients. Here we describe a completely ionizing-radiation-free in vivo near-infrared (NIR) fluoresence dental imaging with indocyanine green (ICG) agent that has rarely been applied in dental imaging. Our method can acquire dental structure images within a short period (only 10 minutes after injection) without ionizing radiation risk. NIR enables the observation of dental structures that are not distinguishable under visible conditions. At prolonged 72 hours, only molar regions remained highlighted; the contrast between molar regions and surrounding tissues was prominent; this is particularly useful for in vivo dental imaging. Using the quantitative spectral analysis, we found the peak wavelengths of ICG fluorescence shifted along with the injection time: the peak wavelength shifted 8 nm (from 819 nm to 811 nm) in 0~72 hours. The injection methods of tail vein v.s . intradermal injections caused ~3 nm shift. ICG-assisted NIR fluorescence imaging can serve as a useful tool for in vivo real-time diagnosis in dental clinics and surgeries without ionizing radiation risk.

Broad spectrum antibacterial photodynamic and photothermal therapy achieved with indocyanine green loaded SPIONs under near infrared irradiation

“…Indocyanine green (ICG), a FDA approved NIR organic dye, is used for intraoperative optical imaging in the clinic [22,23] and for dental imaging [24]. It is under investigation for imageguided PDT and, most recently, as a photosensitizer for combined PDT-PTT upon irradiation at 808 nm [25].…”

Development of Surgical and Visualization Procedures to Analyze Vasculatures by Mouse Tail Edema Model

“…Although application of PB is a feasible procedure, detection of fine (neo) vasculature system is often not possible due to its relatively low sensitivity by optical wave length-light. Hence, visualization and in vivo imaging by various dye injection is becoming frequently reported [ 21 – 24 ]. Injected PB after the current procedure showed the successful ligation and enlargement of the main L.V.…”

Detection and analysis of enamel cracks by ICG‐NIR fluorescence dental imaging

“…37,38 In our previous research we demonstrated the feasibility of indocyanine green (ICG) for dental imaging in the rat model and human extracted tooth. [39][40][41][42][43][44] We found that ICF-NIR fluorescent (ICG-NIRF) imaging could diagnose several typical diseases in human extracted teeth, such as caries lesions, decay, and insidious caries. 42,43 In particular, we compared ICG-NIRF dental imaging with X-ray imaging.…”