# The Effect of Insertion Angles and Depths of Dental Implant on the Initial Stability
## 3 Results
### Differences of PTV and ISQ among the Three Inserted Angulation  
Regarding the effect of the three angles (vertical, 17\({}^{\circ}\) and 30\({}^{\circ}\) insertion angles) of the implants on the PTV (Figure 4a,b), the groups that had the implants inserted into the distal subcrestal position had no significant difference compared with the PTV along the mesial direction, using the PTV of Group 1 as a reference. The measurement results of the PTV along the distal direction indicated that the 17\({}^{\circ}\) tilted implant had a higher PTV than vertical and 30\({}^{\circ}\) tilt implants. The PTV of the 30\({}^{\circ}\) tilted implant had no significant difference compared with that of the vertical implant. Regarding the mean PTV of the buccal and lingual group, the PTV of the 17\({}^{\circ}\) tilted implant was higher than that of the vertical and 30\({}^{\circ}\) tilted implants. The PTV of the 30\({}^{\circ}\) tilted implant exhibited no significant difference compared with that of the vertical implant. In the groups that inserted the fixture into the mesial supracrestal position, the PTV of the 30\({}^{\circ}\) titled implants was significantly higher than all the directions of the 17\({}^{\circ}\) titled implants and vertical implants.  
Regarding the effect of the tilt angles (vertical, 17\({}^{\circ}\) and 30\({}^{\circ}\)) on the ISQ of the fixture (Figure 4c,d), the mean along the four directions was used to indicate the effect of insertion angle on ISQ because  
Figure 4: PTV (**a,b**) and ISQ (**c,d**) measurements of Groups 1, 2 and 4 and Groups 1, 3 and 5.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Group**} & \multirow{2}{*}{**Implant Angulations and Inserted Type**} & \multicolumn{2}{c}{**Correlation \(\mathbf{\upsilon}\) and \(\mathbf{p}\) between the ISQ and Different Measurement Direction of PTV**} \\ \cline{3-5}  & & **Mean of Four Direction** & **Mevial Direction** & **Distal Direction** & **Mean of buccal and** **Lingual Directions** \\ \hline \multirow{2}{*}{1} & vertical implant with & \(r=-0.85\) & & & \\  & & (\(p=0.04\)) & & & \\ \multirow{2}{*}{2} & 17\({}^{\circ}\) tilted implant with & & \(r=0.384\) & \(r=0.178\) & \(r=-0.949\) \\  & & & (\(p=0.523\)) & (\(p=0.775\)) & (\(p=0.014\)) \\ \multirow{2}{*}{3} & 17\({}^{\circ}\) tilted implant with & & \(r=-0.673\) & \(r=-0.142\) & \(r=-0.345\) \\  & & (\(p=0.213\)) & (\(p=0.82\)) & (\(p=0.57\)) \\ \multirow{2}{*}{4} & 30\({}^{\circ}\) tilted implant with & & \(r=-0.968\) & \(r=-0.711\) & \(r=-0.636\) \\  & & (\(p=0.007\)) & (\(p=0.178\)) & (\(p=0.249\)) \\ \multirow{2}{*}{5} & 30\({}^{\circ}\) tilted implant with & & \(r=-0.200\) & \(r=-0.285\) & \(r=-0.292\) \\  & & (\(p=0.74\)) & (\(p=0.642\)) & (\(p=0.634\)) \\ \hline \hline \end{tabular}
\end{table}
Table 3: Correlations between the ISQ and the PTV along various measurement directions in the five groups.  
the ISQ was not affected by measurement direction in all groups. Using the ISQ of Group 1 as the reference, for the groups that had the fixtures inserted into the distal subcrestal position, no significant difference was evident among three groups. For the groups that had the fixtures inserted into the mesial supracrestal position, vertical insertion and the 17\({}^{\circ}\) tilted angle did not exhibit any significant difference in their ISQs. However, the ISQs of the vertically inserted and 17\({}^{\circ}\) titled implants were significantly higher than the ISQ of the 30\({}^{\circ}\) titled implant.