# Analysis of 3D-Printed Zirconia Implant Overdenture Bars
## 4 Discussion
In comparison to the work currently in progress by the first author, the average weight of an AM titanium alloy solid implant bar was 5.326 g, and  
Figure 15: Images depicting the fracture location on the AM solid zirconia implant bar. an AM lattice-structured titanium alloy implant bar was 4.221 g. The consistent pattern of reduced weight suggests that lattice structuring is an effective strategy for decreasing the overall mass of prosthetic components, regardless of their material composition. This weight reduction has potential clinical significance when considered in conjunction with findings from [PERSON] et al., who evaluated the impact of prosthesis weight and the number of implants on peri-implant bone microstrain. Their results showed a direct correlation between prosthesis weight and bone strain: heavier prostheses produced greater strain [25]. At the time of this investigation, the average cost for bar fabrication was approximately USD 570 per bar. In comparison, a milled titanium implant bar varied tremendously, but the cost averaged at USD 750 per bar. The AM zirconia bar suggests savings of USD 180/bar. The savings do not consider the fact that many AM zirconia bars can be printed at the same time. For this study, seventeen (17) bars were fabricated at the same time. Conversely, milled metal implant bars are cut from a solid disc, and each disc may provide 4-5 bars in one milling session. The AM zirconia bar avenue would ultimately result in greater cost savings, due to the ability to fabricate several bars at once. Moreover, the lattice-structured zirconia bars used less material and would therefore cost less than the solid bars. Further research is required to explore objective efficiency/sustainability metrics. The work of [PERSON] et al. [26] compared the stress-strain patterns of implants with different superstructure materials using 3D finite element analysis (FEA). The findings indicated that a stiffer superstructure reduced stress on the implants and screws, highlighting zirconia as a potential material choice. Unfortunately, zirconia's bi-layered structure poses a fracture risk, and alternative forms should be explored [26]. The AM zirconia bars \begin{table}
\begin{tabular}{c c} \hline \hline
**Solid Bar** & **Weight (g)** \\ \hline  
Average and standard deviation & 6.93 \(\pm\) 0.148 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Weight of AM zirconia bars. presented in this investigation can act as a zygomatic superstructure and circumvent the bilayer concern. Further research is required to explore this. Titanium-based dental implants have been renowned for their biocompatibility and durability; however, recent studies have raised concerns about the release of titanium particles during implantation, function, and maintenance. During the surgical phase, frictional forces at the bone-implant interface may release metallic debris, ranging in size from nanometers to micrometers. Research has indicated that up to 0.5 mg of metallic particles can be introduced into surrounding tissues, contributing to local inflammation and possible disruption of osseointegration [27; 28]. The micro-gap at the implant-abutment interface may facilitate biofilm formation, which accelerates corrosion and particle detachment. Corrosive conditions, such as those created by acidic environments, degrade the titanium oxide layer, leading to nanoparticle generation [27; 28]. Corrosion byproducts can also alter the microenvironment of peri-implant tissues, triggering biological responses, including a higher risk of peri-implantitis [29; 40; 41]. Implant micromovements caused by function, known as \"fretting,\" may result in the release of titanium particles that migrate beyond the implant site to distant organs, such as the lungs and liver [40]. The interaction between chemical, mechanical, biological, and material factors requires further investigation into material options for implant dentistry.