# Evaluation and Comparison of Cortisol Levels in Saliva and Hair among Dental Students
## 4 Discussion  
The stress hormone cortisol has been evaluated repeatedly in different populations, and variable cortisol levels have been found to be expressed in different body parts [1; 2; 3; 4; 5; 6; 18; 19; 20]. This present study aimed to assess and contrast the cortisol expressions, utilizing the saliva and hair samples of undergraduate dental students at two different time intervals. The findings of the present study showed that there were non-significant variations between the cortisol levels in the saliva and hair at the two time points for the female subjects but significant differences between the levels in the male participants' saliva and hair at the two time points. Additionally, the comparisons between the cortisol levels of the saliva specimens and the hair specimen's collections showed substantial variations in the cortisol levels. Numerous studies have shown a significant correlation between salivary and hair cortisol concentrations [6; 7; 21; 22]. It happens as a result of the adrenal glands' simultaneous release of cortisol into the blood and the blood's subsequent diffusion of cortisol into saliva. As a result, the blood is what determines the salivary cortisol levels at a certain time [6; 7; 23; 24]. Cortisol expression levels in hair, on the other hand, have been documented as being moderate to weak. While cortisol concentrations in hair reflect levels of free cortisol similarly to measurements of cortisol in saliva, cortisol concentrations in hair also provide a valid long-term indication (in months) of the activity of the systemic response to chronic stresses [19; 22; 25]. Hair has become more intriguing as a noninvasive sample material for clinical diagnostic and research purposes due to the necessity for retrospective data regarding the technique for cortisol evaluation in human hair samples [19; 22; 25; 26; 27]. Although many likely mechanisms have been put out, it is still unknown how cortisol enters hair. The most widely recognized theory in this regard is cortisol diffusion from follicular capillaries into the medulla of the hair shaft during growth due to its low molecular weight and lipophilic qualities, which make it simple for the molecule to enter cells [9]. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Samples Collection** & **Gender** & **Specimens** & **\({}^{\star}\) Mean** & \begin{tabular}{c} **Std.** \\ **Deviation** \\ \end{tabular} & \
\begin{tabular}{c} **Std. Error** \\ **Mean** \\ \end{tabular} &
\begin{tabular}{c} **Paired** \\ **Differences** \\ \end{tabular} & \({}^{\star\ast}\)_p_-Value** \\ \hline \multirow{4}{*}{First Visit} & Male (n = 79) & Saliva & 1.799 & 0.508 & 0.057 & \multirow{4}{*}{0.355} & \multirow{4}{*}{0.000} \\ \cline{2-3} \cline{5-5}  & (n = 79) & Hair & 1.443 & 0.797 & 0.089 & & \\ \cline{2-3} \cline{5-5}  & Female & Saliva & 1.262 & 0.509 & 0.060 & & \\ \cline{2-3} \cline{5-5}  & (n = 72) & Hair & 0.965 & 0.702 & 0.082 & & \\ \hline \multirow{4}{*}{Second Visit} & Male (n = 79) & Saliva & 1.287 & 0.670 & 0.075 & \multirow{4}{*}{0.601} & \multirow{4}{*}{0.000} \\ \cline{2-3} \cline{5-5}  & Male (n = 79) & Hair & 0.686 & 0.572 & 0.064 & & \\ \cline{1-1} \cline{2-3} \cline{5-5}  & Female & Saliva & 1.318 & 0.734 & 0.086 & & \\ \cline{1-1} \cline{2-3} \cline{5-5}  & (n = 72) & Hair & 0.903 & 0.634 & 0.074 & & \\ \hline \hline \end{tabular}  
* Mean value was recorded in microliters; **\(p\)-value was significant at \(p\) < 0.05.  
\end{table} 
Table 4: Gender wise comparison of cortisol levels in saliva and hair specimens of the participating students at two time intervals (N-151).