326 - Monitoring Occlusal Caries on Primary Teeth with Optical Coherence Tomography

Purpose: To observe changes in the structure and activity of early occlusal caries on primary teeth using Cross-Polarization Optical Coherence Tomography (CP-OCT). The hypothesis is that CP-OCT will be able to successfully identify the presence of a transparent surface zone of reduced reflectivity that is indicative of remineralization and an arrested lesion.

Methods: Participants (n=29 with 59 primary molars) aged 6-10 years old with high caries risk participated in the study. All lesions were monitored over a 6-month period and scanned with CP-OCT during the 0-month, 3-month and 6-month visits. Fluoride varnish was applied to all lesions to promote remineralization. Images were converted and analyzed with image analysis software.

Results: OCT scans showed that 58 teeth (98%) had pit and fissure lesions. There were increasing number of teeth showing a distinct surface zone over 6 months (n=14 (24%) at 0-month, n=25 (43%) at 3-month, n=24 (42%) at 6-month). Out of all teeth with active lesions at 0-month, n=13 (30%) teeth developed a surface zone at 6-month. Out of all teeth with arrested lesions at 0-month, n=3 (21%) teeth became active and no longer showed a distinctive surface zone at 6-month.

Conclusions: OCT can detect early occlusal caries that cannot be identified on radiographs or through a clinical exam. It can provide information on lesion activity by detecting the presence of a transparent surface zone, indicative of lesion arrest. OCT is a valuable diagnostic tool that can aid with diagnosis of early occlusal caries.