## 4 Discussion  
Our proposed novel MAD design not only maintained a wide upper airway, but also controlled the induced force. The presence of a supporting shield in the newly proposed MAD produced a change in the contact area between the device and oral structures, causing a different stress distribution on the front teeth and gingival area. This was confirmed by FE analysis. Factors that influence patient compliance with the use of an MAD include side effects such as discomfort, mouth dryness, gum irritation, excessive salivation, and pain. Additionally, side effects associated with occlusal changes, such as overjet, overbite, and incisor inclination in occlusion, have been reported for long-term use [7; 9; 16]. Larger forces produce larger occlusal changes, which progressively decrease the advancement of the lower jaw, resulting in a reduced therapeutic effect on SDB. In addition, excessive overstretching can adversely affect the shape of the soft tissue structures in the upper airway and the tension of the muscles involved [4]. A device that can minimize occlusal changes would lead to a reduced risk of having to keep the mandible continuously advanced [24]. A device that can be more easily adaptable with an appropriate anatomic fit would also provide more comfort to patients, resulting in increased compliance. FE analysis is an interpretation program that provides the researcher with flexibility in options. It can predict stress values and their distribution while handling external forces at any level. It also provides accurate analyses before and after specific modifications. In addition, there are no limitations to the materials that can be used for testing, which makes it more cost-effective and time-efficient than animal experiments [13; 14; 25]. FE analysis is used in the analysis and design of medical devices, including dental braces [13; 14; 26]. Moreover, the computational mechanobiological algorithms for developing a suitable and optimized design \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**MAD**} & \multicolumn{6}{c}{**Position (MPa)**} & \multicolumn{3}{c}{**Stress**} \\ \cline{2-7}  & **a** & **b** & **c** & **d** & **e** & **f** & **Mean \(\pm\) STD** \\ \hline Conventional & \multirow{3}{*}{0.080} & \multirow{3}{*}{0.102} & \multirow{3}{*}{0.070} & \multirow{3}{*}{0.112} & \multirow{3}{*}{0.040} & \multirow{3}{*}{0.023} & \multirow{3}{*}{0.071\(\pm\) 0.034} \\ (Figure 5a) & & & & & & & \\ Proposed & \multirow{3}{*}{0.063} & \multirow{3}{*}{0.048} & \multirow{3}{*}{0.058} & \multirow{3}{*}{0.065} & \multirow{3}{*}{0.023} & \multirow{3}{*}{0.040} & \multirow{3}{*}{0.050\(\pm\) 0.016} \\ (Figure 5b) & & & & & & \\ Proposed/Conventional & 0.79 & 0.47 & 0.83 & 0.58 & 0.58 & 1.73 & 0.70 \\ \hline \hline \end{tabular} STD, standard deviation; MPa, megapascal; unit of pressure equal to \(10^{6}\) pascals.  
\end{table} 
Table 2: Comparison of stresses between the conventional and proposed MAD. Figure 4: Stress distribution from FE analysis: (**a**) conventional and (**b**) proposed MAD. Figure 5: Comparative analyzed points of stress distribution: (**a**) conventional and (**b**) proposed MAD. of medical devices are currently being tried in many clinical applications [26; 27]. Here we have demonstrated that quantitative visual analysis can be applied to MADs using FE analysis and that there are advantages to this method. A novel simulation program using FE analysis and computational mechanobiological algorithms will be valuable in minimizing the side effects and developing advanced MADs for patients with skeletal deformities, such as a retrognathic mandible and constricted maxilla. Close collaboration between clinicians and mechanical engineers is essential. Our novel MAD design can enhance comfort in attachment and detachment because the upper and lower trays can be inserted separately, controlling tension through the springs. However, further studies including clinical trials are needed to confirm these points.