Alongside Dr. Keller's recognition in Denistry nowadays,Dr. Robert J. Van Dyke, DDS wrote this letter approximately his experience with Perio Protect and Dr. Keller:
My first introduction to Dr. Duane Keller was at his Perio Protect Certification meeting in Las Vegas. My worthy friend and consultant, or Bob Maccario said it was a meeting I just had to go to. As I sat in the seminar,I was mesmerized by the science I was hearing from a dentist. Then I realized that Dr. Duane Keller is no ordinary dentist.
Source: drduanekeller.com