Chin Implant Materials and what are the chin implants made of? what options would i have when i meet with a surgeon?

There are a variety of shapes and sizes to implants.
Shapes generally range from button like to progressively larger and longer shapes that wrap around and "hug" the mandible (jaw bone) and are called anatomic.
The most common implants are made of silicone-like rubber.
Other implants have been made of:
Porous polyethylene: a firm bone like plastic and generally are composed to two pieces which lock together due to their inability to bend when placed in a small incision. One tradename is Medpor
Calcium hydroxyapatite: a bone like material which is either molded in a chin like shape or available in an injectable paste
PTFE aka Gortex like substance that is similar to a dense foam
Mesh usually composed of a suture polypropylene material that is layered and formed into an implant by the surgeon and goes by the tradename of Prolene or Marlex.
Custom fabricated implants from a poylmethylmethacrylate material (plastic cement like substance).
Implants can also be autogenous meaning they come from you and can be composed of cartilage (usually your ribs) or bone (skull, hip, rib), etc.
Rarely, the appearance of an enlarged chin can be achieved with injectable materials or autogenous fat.
Lastly, the jaw bone can be rearranged in a procedure called an osseous genioplasty.
I hope this helps!

There are extended anatomical chin implants and pre-jowl chin implants (these give a little more fullness in the pre-jowl area). These are the two most frequently used.
The implants can be made of either Silicone or Goretex.