## 3 Results  
### Measurements for Bone Gain Analysis  
Bone gain measurements were conducted by comparing each patient's preoperative and 6-month post-operative CBCT data. Specifically, parasagittal images of the respective CBCTs were used as a reference for measuring bone defects. Mandibular bone defects were measured from the lower margin of the inferior alveolar nerve to the coronal portion of the bone defect. This approach aimed to prevent titanium mesh radiopacity from influencing post-operative result measurements, ensuring a complete identification of the inferior alveolar nerve. The measurements were performed by using the software Horos Viewer(tm) (v.4.0.1) as shown in Figure 3.  
Figure 3: Example of measurements performed on CBCT using the Horos Viewer(tm) software: pre-intervention and 6 months post-GBR (case n.10). The obtained results are summarized in Table 2. By comparing these data with those in Table 1, where measurements in terms of height, B-O extension (buocal-oral), and M-D extension (mesio-distal) are presented, it can be observed that in all cases, there was a sufficient bone increase, enabling the final placement of 24 total implants in 10 sites treated with the GBR technique. All implants were placed following computer-guided planning. In fact, as demonstrated by various studies, Computer-Assisted Implant systems for implant surgery have the potential to improve the safety and precision of implant insertion [17]. In particular, Table 3 shows the bone gain, calculated by taking the difference between values from Table 1 and values from Table 2.  
The parameters considered are Height in mm for vertical bone gain and Buccal- Oral Extension for horizontal bone gain. The average values, calculated by the arithmetic mean of vertical and horizontal bone gain, are as follows:  
- Average vertical bone gain: 5.4 mm;  
- Average horizontal bone gain: 4.3 mm. In all analyzed cases, a specific bone gain was achieved (Table 3) compared to the pre-intervention period (Table 1), allowing for successful implant-prosthetic rehabilitation of the patients. It can be inferred that predictable results can be attained through GBR \begin{table}
\begin{tabular}{c c c c c c c} \hline
**Patient** & **Membrane** & **Height** & **B-O** & **M-D** & **Number** & **Implant** \\  & **Exposure** & **(mm)** & **Width (mm)** & **Width (mm)** & **Implant** & **Placennet Site** \\ \hline
1. & no & 18.9 & 8.8 & 24 & 2 & 1.2–2.2 \\
2. & no & 17.2 & 5.8 & 10.1 & 2 & 3.2–3.5 \\
3. & no & 16.2 & 11.6 & 23.1 & 2 & 4.6–4.7 \\
4. & no & 10.6 & 9.3 & 12 & 1 & 4.5 \\
5. & yes & 12.8 & 7.1 & 22.5 & 3 & 1.1–2.1–2.3 \\
6. & yes & 14.5 & 6.1 & 31 & 5 & 3.2–3.3–4.1–4.3– \\
7. & yes & 11.3 & 6.7 & 21 & 2 & 1.2–1.4 \\
8. & no & 8.9 & 8.5 & 24 & 3 & 2.2–2.4–2.6 \\
9. & no & 11.8 & 8.2 & 31.2 & 2 & 4.4–4.6 \\
10. & no & 7.8 & 9.4 & 18.2 & 2 & 1.4–1.6 \\ \hline \end{tabular}
\end{table} 
Table 2: The table displays the results obtained in terms of membrane exposure, height in mm, B-O extension (buocal–oral), M-D extension (mesio-distal) of the reconstructed bone, number of inserted implants, and implanted area. \begin{table}
\begin{tabular}{c c c} \hline
**Patient** & **Vertical Bone Gain (mm)** & **Horizontal Bone Gain (mm)** \\ \hline
1. & 1.4 & 5.7 \\
2. & 5.7 & 3.7 \\
3. & 10.9 & 7.0 \\
4. & 1.1 & 4.0 \\
5. & 5.7 & 4.9 \\
6. & 3.2 & 3.8 \\
7. & 6.8 & 2.7 \\
8. & 4.7 & 5.0 \\
9. & 10.3 & 2.3 \\
10. & 4.1 & 3.9 \\ \hline \end{tabular}
\end{table} 
Table 3: Table 3: Table 3 illustrates the achieved vertical and horizontal bone increases. intervention with custom-made membranes. However, membrane exposure in titanium was observed in 30% of cases. Comparing the average values of bone gain in exposed and non-exposed cases (Table 4), we note that in the former, the increase was less pronounced than in cases without exposure. This suggests that there has been bone resorption in cases of membrane exposure.