My son went to him. He had to get several fillings. One filling fell out 7 different times that Dr. Willenborg did. Seven times! I finally on the 7th time went back into the room with my 17 year old son to ask the dentist why it was falling out constantly. He just shrugged his shoulders and said "I don't know!" I was speechless. Anyway, it fell out the 7th time. I had enough and we changed dentist. The new dentist filled the tooth. No problems. But, hear this. Every single filling that Dr. Willenborg did had to be replaced that he had done on my son previously. Dr. Willenborg had not cleaned out the decay all the way before filling them. He left a substance on the teeth as well our new dentist said that also caused decay. The bill to fix my son's teeth was over $1500. Our dental insurance covered most of it. But, my son had to endure pain and miss school twice due to this beyond incompetent dentist.