A Hello and thank you for your question. Fillers used in the temples are usually injected deeper whether it is Radiesse or Voluma. In the cheeks, however, fillers can be injected into different planes depending on what is used.
Radiesse is a calcium based filler that is white in color and more of a paste-like consistency. That being said, it is best when injected deep, right onto bone, in areas like the temples or zygoma. Voluma, on the other hand, is a hyaluronic acid based filler with a gel-like consistency and can be injected deep onto bone or sub-dermally. Both of these fillers are meant for volume replacement and are thicker in consistency which means superficial injections are not recommended.
Both are great fillers for creating a natural look. Be sure you are seeking an experienced injector who specializes in facial aesthetics for best results and guidance. Good luck!