**4. Conclusion**

rubber after 90 days, but positive staining in the carbon ion silicone rubber decreased with time. After 90 days, CD4 significantly decreased compared with silicone rubber (**Table 3**).

In addition, the expression results of proinflammatory cytokine tumor necrosis factor-α by macrophage cells show that silicone rubber had an obviously positive staining area (**Table 4**). Furthermore, the positive staining areas of α-smooth muscle actin and elastin have no difference; the positive staining area of α-smooth muscle actin appeared predominantly in silicone rubber than in carbon ion silicone rubber (**Table 5**). Elastin was intensely expressed in silicone

**7 days 30 days 90 days 180 days**

**7 days 30 days 90 days 180 days**

**7 days 30 days 90 days 180 days**

**7 days 30 days 90 days 180 days**

SR ++ ++ +++ +++ C1-SR +++ ++ + + C2-SR ++ ++ ++ ++ C3-SR ++ + + +

SR ++ ++ +++ +++ C1-SR ++ ++ + + C2-SR +++ + + + C3-SR ++ + + +

SR ++ +++ +++ ++ C1-SR + ++ ++ + C2-SR ++ + ++ + C3-SR ++ ++ + +

SR + ++ ++ ++ C1-SR + + + + C2-SR + + + + C3-SR + + + +

rubber, particularly after 30 days (**Table 6**).

138 Ion Implantation - Research and Application

**Table 3.** Semiquantitative evaluation of CD4 in peri-implant tissue.

**Table 4.** Semiquantitative evaluation of TNF-α in peri-implant tissue.

**Table 5.** Semiquantitative evaluation of α-SMA in peri-implant tissue.

**Table 6.** Semiquantitative evaluation of elastin in peri-implant tissue.

Our study evaluated the in vitro antibacterial properties and the in vivo host response to carbon ion-implanted silicone rubber. The results of our study indicate that the carbon ion silicone rubbers have good biocompatibility, lower bacterial adhesion, and lower foreign body reaction with relatively thin fibrous capsules. All results show that ion implantation should be considered for further investigation and application, and carbon ion silicone rubber might be a better biomaterial for decreasing silicone rubber-initiated complications.
