Can I Have a Hyaluronic Acid Filler Put in over Radiesse in my Nasolabial Folds?

Filling the area with Restylane should be fine. I may recommend waiting a full two weeks after the Radiesse injection to make sure all swelling has gone down. Best of luck!

Waiting a full two weeks to let any swelling heal would be ideal. After that, there is no issue with having a HA filler injected to the area

It is definitely possible and not uncommon to place a hyaluronic acid filler, such as Restylane, over an area that has been previously treated with Radiesse.  There should be no problem with this approach.  

Using a hyaluronic acid filler over Radiesse is a great way to fine tune results in the nasolabial fold. Each filler is slightly different, and you can optimize your results by using both. Since Restylane is dissolvable, it is safer to use in the upper cheek by the nose. There is a large blood vessel there (the angular artery), which is probably why your new injector avoided the area with Radiesse (not dissolvable).  Small amounts of Restylane injected slowly is a better bet in that area. 

Not only is this possible but it can be used to create a more refined appearance. A thicker, heavier filler can provide volume and lift while a thinner, hyaluronic acid filler can be used to treat overlying finer lines. Seek an experienced physician injector (Plastic Surgeon or Dermatologist) for the highest probability of a great result. I hope this information is helpful.

Yes, hyaluronic acids can usually be injected over radiesse for a layered effect.  When patient do not obtain the results they seek after fillers, it is usually the result of one of two reasons: 1) skill of the injector and/or 2) dividing a syringe of filler over multiple areas as there is not enough filler to revolumize those areas for full correction.  Often times, patients are enticed by costs that seem too good to be true, only to find that the injector is not a board certified specialist (e.g. facial plastic surgeon, plastic surgeon, dermatologist, or oculoplastic surgeon) or a smaller sized syringe.  Please consult with a board certified specialist who can assist you with achieving the results you seek.