# Estimation of Age in Humans Using Dental Translucency of Permanent Teeh: An Experimental Study
## 3 Results
ICC for RH indicates excellent reliability in the oldest group and single-rooted teeth, good reliability in the 40-59 years old group and multi-rooted teeth, and moderate in the youngest group. In general, the reliability of the total sample was good. The inter-operator reliability for the PH \begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Variables** & \begin{tabular}{l} **Total Sample** \\ **Mean (SD)** \\ \end{tabular} & \begin{tabular}{l} **Group 1** \\ **(18–39 Years)** \\ **Mean (SD)** \\ \end{tabular} & \begin{tabular}{l} **Group 2** \\ **(40–59 Years)** \\ **Mean (SD)** \\ \end{tabular} & \
\begin{tabular}{l} **Group 3** \\ **(60+ Years)** \\ **Mean (SD)** \\ \end{tabular} &
\begin{tabular}{l} **\(p\)-Value 1** \\ **Mean (SD)** \\ \end{tabular} & **Post-Hoc Test** \\ \hline \hline \multicolumn{6}{l}{_Total sample (\(n\) = 155)_} \\ \hline RH (mm) & 12.64 (2.32) & 11.38 (1.74) & 12.88 (2.12) & 13.32 (2.48) & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline PH (mm) & 2.60 (1.46) & 1.68 (1.49) & 2.82 (1.14) & 3.05 (1.42) & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline RHT (mm) & 4.69 (3.36) & 0.41 (0.88) & 5.35 (2.11) & 7.08 (2.27) & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline \multicolumn{6}{l}{_Males (\(n\) = 63)_} \\ \hline RH (mm) & 13.20 (2.58) & 11.56 (2.39) & 12.89 (2.41) & 13.95 (2.51) & 0.022 & **1 \textless{} 3** \\ \hline PH (mm) & 2.69 (1.43) & 0.95 (1.17) & 3.01 (1.24) & 3.01 (1.26) & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline RHT (mm) & 5.63 (3.45) & 0.51 (1.28) & 5.13 (2.46) & 7.70 (2.38) & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline \multicolumn{6}{l}{_Females (\(n\) = 92)_} \\ \hline RH (mm) & 12.26 (2.05) 1 _ & 11.31 (1.49) & 12.86 (1.94) & 12.69 (2.32) 2  & 0.004 & **1 \textless{} \textless{} 2, 3** \\ \hline PH (mm) & 2.54 (1.49) & 1.89 (1.52) & 2.67 (1.06) & 3.08 (1.57) & 0.004 & **1 \textless{} 3** \\ \hline RHT (mm) & 4.05 (3.16) 2 ** & 0.37 (0.71) & 5.51 (1.85) & 6.45 (2.00) 2  & \textless{}0.001 & **1 \textless{} 2, 3** \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Mean and standard deviation of the considered tooth measures (RH, PH, and RHT) in the total sample and for each sex separately, divided by age classes. \begin{table}
\begin{tabular}{l l l l} \hline \hline \multicolumn{2}{l}{_Intra-operator variability (A1–A2)_} \\ \hline  & \begin{tabular}{l} **RH ICC (95\% CI)** \\ **(N = 155)** \\ \end{tabular} & \begin{tabular}{l} **PH ICC (95\% CI)** \\ **(N = 111)** \\ \end{tabular} & \begin{tabular}{l} **RHT ICC (95\% CI)** \\ **(N = 155)** \\ \end{tabular} \\ \hline Total sample & 0.947 (0.928–0.961) & 0.942 (0.919–0.959) & 0.973 (0.963–0.980) \\ \hline Single-rooted & 0.938 (0.889–0.966) & 0.917 (0.841–0.956) & 0.927 (0.869–0.959) \\ \hline Multi-rooted & 0.948 (0.926–0.964) & 0.951 (0.929–0.967) & 0.981 (0.972–0.987) \\ \hline \multicolumn{2}{l}{_Inter-operator variability (A1–B)_} \\ \hline  & \begin{tabular}{l} **RH ICC (95\% CI)** \\ **(N = 135)** \\ \end{tabular} & \
\begin{tabular}{l} **PH ICC (95\% CI)** \\ **(N = 97)** \\ \end{tabular} &
\begin{tabular}{l} **RHT ICC (95\% CI)** \\ **(N = 136)** \\ \end{tabular} \\ \hline Total sample & 0.876 (0.824–0.912) & 0.658 (0.323–0.628) & 0.923 (0.887–0.947) \\ \hline Single-rooted & 0.932 (0.859–0.966) & 0.543 (–0.042–0.797) & 0.844 (0.690–0.921) \\ \hline Multi-rooted & 0.818 (0.728–0.878) & 0.692 (0.505–0.808) & 0.933 (0.897–0.956) \\ \hline \hline \end{tabular}
\end{table} 
Table 3: ICC intra-operator (first part) e inter-operator (second part) variability for the total sample by tooth type. measures was generally lower, with moderate reliability in the total sample and a decreased reliability with increasing age. The reliability was good for both tooth types, with higher values for multi-rooted teeth. As regard RHT, the reliability was excellent for the total sample and good in the three age groups considered separately (Table S3). Dividing for tooth type, the reliability was excellent for multi-rooted and good for single-rooted teeth.