## 3 Results
### Obstructive Sites without the TMA Simulator  
We analyzed the individual obstructive sites without the TMA simulator and found that there was no difference in the percentage of velum obstruction (non-responders: 96.1%; responders: 97.6%; \(p\) = 0.515), of the tongue base (non-responders: 53.1%; responders: 58.5%; \(p\) = 0.365) and epiglottis (non-responders: 35.2%; responders: 40.6%; \(p\) = 0.356).  
\begin{table}
\begin{tabular}{c c c c c} \hline  & **Non-Responders** & **Responders [Mean \(\pm\) SD]** & **Difference (CI)** & \(p\) **(t-Test)** \\ \hline AHI (ev/h) & 39.50 \(\pm\) 19.65 & 30.82 \(\pm\) 17.16 & 8.68 (4.66; 12.71) & \textless{}0.001 \\ \hline AHI\({}_{\text{sup}}\) (ev/h) & 51.43 \(\pm\) 21.51 & 46.58 \(\pm\) 21.01 & 4.85 (0.03; 9.67) & 0.049 \\ \hline AHI\({}_{\text{nonsup}}\) (ev/h) & 25.71 \(\pm\) 23.92 & 16.12 \(\pm\) 17.68 & 9.59 (4.86; 14.32) & \textless{}0.001 \\ \hline ODI (ev/h) & 39.69 \(\pm\) 21.13 & 30.98 \(\pm\) 19.66 & 8.71 (4.12; 13.30) & \textless{}0.001 \\ \hline Sat\({}_{\text{med}}\) (\%) & 92.89 \(\pm\) 2.34 & 93.31 \(\pm\) 1.84 & \textless{}0.43 (\textless{}-0.90; 0.04) & 0.075 \\ \hline Sat\({}_{\text{min}}\) (\%) & 76.91 \(\pm\) 8.19 & 79.20 \(\pm\) 8.29 & \textless{}2.28 (\textless{}-4.19; \textless{}-0.37) & 0.019 \\ \hline CT90 (\%) & 14.51 \(\pm\) 17.08 & 9.36 \(\pm\) 11.25 & 5.15 (2.00; 8.30) & 0.001 \\ \hline \end{tabular}
\end{table}
Table 4: Comparison between responders and non-responders: polygraphic indices.  
\begin{table}
\begin{tabular}{c c} \hline Males [\(n\) (\%)] & 307 (91.6\%) \\ \hline Age (years) [mean \(\pm\) SD] & 49.98 \(\pm\) 9.88 \\ \hline BMI (kg/m\({}^{2}\)) [mean \(\pm\) SD] & 28.49 \(\pm\) 3.48 \\ \hline AHI (ev/h) [mean \(\pm\) SD] & 34.14 \(\pm\) 18.61 \\ \hline OSAS mild (5 \(\leq\) AHI \(<\) 15) [\(n\) (\%)] & 54 (16.1\%) \\ \hline OSAS moderate (15 \(\leq\) AHI \(<\) 30) [\(n\) (\%)] & 101 (30.2\%) \\ \hline OSAS severe (AHI \(\geq\) 30) [\(n\) (\%)] & 180 (53.7\%) \\ \hline \end{tabular} \(n\): number; SD: standard deviation; BMI: body mass index; AHI: apnea–hypopnea index.  
\end{table}
Table 2: Demographic and clinical characteristics of the patients included in the study.  
\begin{table}
\begin{tabular}{c c c c} \hline  & **Non-Responders** & **Responders [Mean \(\pm\) SD]** & **Difference (CI)** & \(p\) **(t-Test)** \\ \hline Age (years) & 48.77 \(\pm\) 9.86 & 50.76 \(\pm\) 9.83 & \(-\)1.99 (\(-\)4.23; 0.25) & 0.082 \\ \hline BMI (kg/m\({}^{2}\)) & 29.14 \(\pm\) 3.81 & 28.09 \(\pm\) 3.21 & 1.05 (0.29; 1.82) & 0.007 \\ \hline \end{tabular}
\end{table}
Table 3: Comparison between responders and non-responders: gender, age, and body mass index variables.  
On the contrary, responders showed a significantly lower percentage of obstruction of the oropharynx than non-responders (non-responders: 89.1%; responders: 80.2%; \(p=0.034\)).  
Concerning the number of obstructed sites, the two groups showed no significant differences (non-responders: 2.73 \(\pm\) 0.84; responders: 2.77 \(\pm\) 0.85; \(p\) = 0.686).  
The Venn diagram in Figure 3 shows the distribution of obstructive patterns in patients who did not show a response to mandibular advancement in DISE (Figure 3a) and those who showed a response to mandibular advancement in DISE (Figure 3b). The two distributions did not differ statistically (\(p\) = 0.131).