Imaging artificial caries under composite sealants and restorations

Area of Science:

• Biomedical Optics
• Dental Imaging
• Materials Science

Background:

• Dental caries detection remains a challenge, particularly beneath restorative materials.
• Non-destructive imaging techniques are crucial for monitoring early demineralization.
• Optical coherence tomography (OCT) offers high-resolution cross-sectional imaging.

Purpose of the Study:

• To evaluate the efficacy of polarization-sensitive optical coherence tomography (PS-OCT) in monitoring simulated caries progression on occlusal surfaces.
• To assess the capability of PS-OCT in imaging artificial caries lesions located beneath composite sealants of varying thickness.
• To determine the impact of sealant opacity and thickness on imaging depth and lesion detectability.

Main Methods:

• PS-OCT system utilized to acquire images in parallel and perpendicular polarization channels.
• Simulated caries lesions created on occlusal surfaces and monitored over 14 days.
• Lesions imaged under composite sealants of varying thickness (250-1000 micrometers).
• Reflectivity changes analyzed to quantify lesion progression and detectability.

Main Results:

• PS-OCT demonstrated significant enhancement in contrast for artificial caries, reducing surface reflection interference.
• A mean reflectivity increase of 5.1 dB was observed in lesions from day 0 to day 14 (p<0.01).
• Artificial lesions were detectable under 750 micrometers of opaque sealant (5.0 dB difference, p<0.001) and 1000 micrometers of tooth-colored sealant (6.6 dB difference, p<0.001).

Conclusions:

• PS-OCT is a valuable non-destructive tool for tracking caries lesion progression on occlusal surfaces.
• The technology enables imaging of caries lesions underneath composite sealants, with tooth-colored materials allowing greater imaging depth.
• PS-OCT holds potential for improved clinical monitoring and diagnosis of early dental caries.