A Crack Extension Prediction; Connecting Crown And Root Dimensions

To evaluate the efficacy of advanced imaging techniques—Micro-Computed Tomography (Micro-CT), Dental Operative Microscopy (DOM), and Micro-Lens Cameras—in assessing crack propagation in dental structures and to derive a standard equation correlating crack length and depth for early clinical diagnosis. Sixty extracted intact human teeth were subjected to controlled thermal cycling (liquid nitrogen to boiling water) to simulate natural stress-induced cracks. Crack measurements were performed using DOM, Micro-Lens Cameras, and Micro-CT. The most precise imaging modality (Micro-CT) was identified and used to establish a correlation between crack length and depth. Statistical analyses, including correlation coefficients, linear regression, and significance testing (p < 0.01), were conducted using SPSS v26 to derive a predictive equation. A strong positive correlation (r = 0.769, p < 0.01) was observed between crack length and depth, leading to the derivation of the equation D = 1.69 + (1.13 × L), where D represents crack depth and L represents crack length. Micro-CT demonstrated superior accuracy in visualizing crack propagation due to its high-resolution three-dimensional imaging, whereas DOM and Micro-Lens Cameras were effective for surface-level crack detection but limited in assessing internal structures. Micro-CT provides the highest precision in detecting and measuring crack dimensions in dental structures. The derived equation offers a non-invasive diagnostic tool for clinicians, facilitating early and accurate identification of crack progression, thereby enhancing treatment planning and long-term patient outcomes.