A 1CC syringe contains 1/5 of a teaspoon. If you have a measuring teaspoon set in the kitchen, you can see how much that actually is. Knowing where (and where not) to place filler makes a huge difference in the effects you can get. But from your question. if your cheeks show noticeable concavity, it is extremely unlikely a single syringe of any filler can get the job done. You do have options as to the kind of filler you can use to increase volume - Sculptra is high on the list because it is actually a stimulator for collagen so you get "fill" that is natural, but that action does take time and several sessions to get the best outcomes. Gel fillers make an instant improvement but they don't last as long. The new Juvederm Voluma on the market soon may have better longevity. Radiess can be used in some areas and is instant with a longer term life than hyaluronic gels. Radiesse has more product in a syringe - but even then, it is doubtful that a single Radiesse syringe would improve both sides of your face.