(PR121) Intraoral-tomosynthesis Accuracy for Cone Length Measurement is Comparable to Physical Measurement of Gutta-percha

Objective: To assess the efficacy of cone fit measurements of digital periapicals and tomosynthesis images and compare them to the physical measurement of the gutta-percha.

Methods: Images were captured by digital periapical and 3d-intraoral tomosynthesis device (Portray system). Images of 40 extracted teeth with gutta-percha in their prepared root canals were taken. The physical cone length of the gutta-percha was measured using a digital vernier caliper. The digital periapical cone length was measured using MiPACS Dental Enterprise Viewer Software with a polyline measurement tool. Cone length in the tomosynthesis images was measured by scrolling through synthetic images taken at a different viewing angle. These synthetic images were the computer-generated 2-D image displays of the processed 3-D information collected by synthetic intraoral tomosynthesis. A polyline measurement was acquired by scrolling through to get a clear view of coronal and apical ends of the gutta-percha. Cone lengths in both imaging systems were compared with the physical measurements. All measurements were recorded and subjected to statistical analysis.

Results: Interclass correlation coefficient (ICC) was used for statistical analysis. All results showed statistical significance. The gold-standard vs tomosynthesis measurements had the highest reliability across all groups, often exceeding 0.9. Comparisons involving periapical (periapical vs gold and periapical vs tomosynthesis) tend to have lower reliability, with several confidence intervals including 0. Statistically significant p-values across all comparisons suggest these ICCs are meaningful, but confidence intervals highlight potential issues with data variability.

Conclusion: While both modalities differed from the gold standard, tomosynthesis demonstrated a clear advantage in measurement accuracy and reliability