Intraoral tomosynthesis accuracy for cone length measurement is comparable to physical measurement of gutta-percha

To assess the efficacy of cone fit measurements of digital periapical (PA) and stationary intraoral tomosynthesis (s-IOT) images and compare them to the physical measurement of gutta-percha (gold standard).

Images of 40 extracted teeth with gutta-percha in their prepared root canals were acquired using digital PA and 3D s-IOT devices (Portray system), while the physical cone length of the gutta-percha was measured using a digital vernier caliper. Digital PA cone length was measured using MiPACS Dental Enterprise Viewer Software with a polyline measurement tool. Cone length in the s-IOT images was measured by scrolling through synthetic images taken at different angle disparities. All measurements were recorded and subjected to statistical analysis.

Interclass correlation coefficient (ICC) test showed statistical significance. The gold standard vs s-IOT measurements had the highest reliability across all groups, often exceeding 0.9. Comparisons involving PA (PA vs gold standard and PA vs s-IOT) 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.

While both modalities differed from the gold standard, s-IOT demonstrated a clear advantage in measurement accuracy and reliability.