Facial implant materials
| Material | Properties and Uses | Imaging Appearance |
|---|---|---|
| Silicone rubber (Silastic) | Rubber elastomer, well-tolerated and easily customizable, soft pliable consistency; indications: chin, lateral jaw, cheek, and nose augmentation | CT: variable attenuation, usually denser than soft tissue, but less dense than bone and best discerned using bone windows; |
| MRI: very low signal intensity on T1- and T2-weighted sequences | ||
| Expanded polytetrafluoroethylene (Gore-Tex) | Biocompatible, long-lasting but can be removed surgically; indications: lower face lift, nasal and forehead augmentation | CT: higher attenuation relative to soft tissues, but less dense than bone; |
| MRI: hypointense to fat on T1- and T2-weighted sequences | ||
| Polytetrafluoroethylene (Teflon) | Obsolete | Imaging features similar to those of Gore-Tex |
| Porous polyethylene (Medpor) | Inert and biocompatible, low complication rate, permanent; indications: lower face and nasal augmentation; also used for orbital and auricular reconstruction; fibrovascular ingrowth can render removal difficult | CT: attenuation between fat and water; |
| MRI: hypointense to fat on T1- and T2-weighted sequences; enhancement may occur due to fibrovascular ingrowth | ||
| Hydroxylapatite | Inert and biocompatible; blocks of hydroxylapatite can allow fibrovascular ingrowth and bony incorporation | CT: hyperdense, hyperattenuation similar to that of bone; the implant can become incorporated into and inseparable from the adjacent bone; |
| MRI: low signal on T1 and T2; enhancement may occur due to fibrovascular ingrowth | ||
| Bone | Occasionally used for rhinoplasty, cheek, and chin augmentation; harvest sites include iliac crest, cranium, turbinates, rib | CT: same as normal bone elsewhere; cortex and trabecular can be identified unless resorption has occurred |
| MRI: high T1 and T2 marrow signal and low-signal cortex are often discernible; in the early postoperative period, marrow edema within the graft may appear as low T1 and high T2 signal | ||
| Cartilage | Often used in rhinoplasty and sometimes chin augmentation; harvest sites include nasal septum, conchal cartilage, and costal cartilage; can be part of osteochondral grafts; can be diced and wrapped in Surgicel (Turkish Delight) | CT: soft-tissue density; may form a rim of calcification or ossification; |
| MRI: usually low T2 and high T2 signal |