Health risks, primarily are due to the actual surgery not the implants themselves.
Blood Clots, Hematomas, Infection, anything to do with surgery has risks and of course these typical any surgery type of risks. Technically they count capsular contraction a risk, but that depends on how your body heals and is individual and you can't really gauage it unless say, you had a surgery before and had a lot of bad hard scar tissue.
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