# Sex Prediction Based on Mesiodistal Width Data in the Portuguese Population
## 4 Discussion  
Sex estimation is a vital step in forensic medicine for body identification both in single and mass disaster events. In the Portuguese scenario, sex estimation models through dental hard tissues are scarce and previous proposed models lacked consistency and only accounted for a small subset of \begin{table}
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**Variables** & \(B\) & \(p\)**-Value** & **EXP (B)** & \multicolumn{2}{c}{**EXP (B) 95\% CI**} \\ \cline{3-6}  & & & & **Lower** & **Upper** \\ \hline Tooth 2.3 & 1.208 & 0.019 & 3.35 & 1.22 & 9.22 \\ Tooth 4.3 & 1.800 & 0.003 & 6.05 & 1.84 & 19.91 \\ Tooth 4.2 & \(-\)1.317 & 0.018 & 0.27 & 0.09 & 0.80 \\ Constant & \(-\)14.546 & \(<\)0.001 & - & - & - \\ \hline \hline \end{tabular} R\({}^{2}\)(N) = 0.268, % correct classification = 75%; H\(\&\)L: X\({}^{2}\) = 6.767 (\(p\) = 0.562); Note: outcome variable (sex) coded as male: 1, female: 0.  
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Table 2: Final reduced logistic regression model (n = 168). \begin{table}
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**Model** & \multicolumn{2}{c}{**Sensitivity**} & **Specificity** & **Accuracy** & **Precision** & **AUC within ROC** \\  & & **(\%)** & **(\%)** & **(\%)** & **(\%)** & **Analysis (95\% CI)** \\ \hline [PERSON] et al., & Model 1 & 85.3 & 50.8 & 73.2 & 76.2 & 0.642 (0.551–0.733) \\
2007 [23] & Model 2 & 13.8 & 93.2 & 41.7 & 78.9 & 0.637 (0.546–0.728) \\ [PERSON] et al., 2014 [4] & 65.1 & 45.8 & 58.3 & 68.9 & 0.681 (0.592–0.770) \\  & Model 1 & 89.9 & 39.0 & 72.0 & 73.1 & 0.535 (0.445–0.625) \\  & Model 2 & 59.6 & 49.2 & 56.0 & 68.4 & 0.555 (0.463–0.646) \\ [PERSON] et al., & Model 3 & 65.1 & 45.8 & 58.3 & 68.9 & 0.644 (0.553–0.736) \\
2016 [5] & Model 4 & 88.1 & 37.3 & 70.2 & 72.2 & 0.544 (0.452–0.636) \\  & Model 5 & 86.2 & 37.3 & 69.0 & 71.8 & 0.555 (0.463–0.646) \\  & Model 6 & 82.6 & 45.8 & 69.6 & 73.8 & 0.627 (0.535–0.719) \\  & Model 7 & 81.7 & 45.8 & 69.0 & 73.6 & 0.618 (0.525–0.710) \\ [PERSON] et al., 2020 & 87.2 & 52.5 & 75.0 & 77.2 & 0.768 (0.693–0.843) \\ \hline \hline \end{tabular} AUC—Area under the curve; ROC—Receiver operating characteristic.  
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Table 3: Performance assessment of the different models when applied to the studied sample. Measures are presented as percentage. For AUC, estimation by a 95% confidence interval (95% CI) is also shown. teeth. Therefore, we aimed to develop a potential model using mesiodistal widths of models cast previously for studies of orthodontic indexes. Then, we compared the performance of this model with other full-mouth mesiodistal models published elsewhere. Overall, our model outperformed all available strategies and might be used as a forensic tool for sex estimation in Portuguese samples. As previously stated, sexual dimorphism may vary between populations, possibly due to a variety of reasons [3,14]. Therefore, this new model arises as a valuable tool to forensic dentistry. Our results have prospective importance. (1) Until now, there were no models developed for the Portuguese population from complete models. (2) Dental hard tissues are of utmost interest because they are the most lasting tissue of human body, even in post-mortem difficult conditions. (3) This tool may be very useful in single or mass disasters or body identification cases in Portugal, especially due to the unpredictability of these situations. (4) These results confirm sexual dimorphism on teeth mesiodistal width in canines, premolars, and molars of the upper and lower arches. Dental crown dimensions can be obtained through intraoral measurements [18], dental forms [4,11,13,14,16,19,24], or human remains [20,21]. The mesiodistal and buccolingual measurements of the crown were the two most commonly used and studied dimensions [1,11,14,18,19,20,21], followed by diagonal measurements (mesiobuccal-distolingual and distobuccal-mesiolingual) [1,21,25] and the canine mandibular index (expressed as the ratio between the mesiodistal dimension of the canines and the width of the intercanine arch [12,15,19,26]).