Saline breast implants. Saline implants are filled with saline, usually at the time of surgery.

顾名思义，里面塞的都是生理盐水，通常在手术时填充。

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Also, some patients are simply more comfortable having saline implants, partly because of the earlier health concerns with silicone.

WSJ: Silicone Breast Implants Make a Comeback

Saline implants are more prone to rippling and other texture changes that can sometimes be seen through the skin, surgeons say.

WSJ: Silicone Breast Implants Make a Comeback

Saline implants require a much smaller incision, meaning less scarring. (The shell of the implant is inserted and only then is it filled with saline.) Removing it is also easier.

WSJ: Silicone Breast Implants Make a Comeback