Dr. Seiden is a wonderful dentist. My wife and I were in DC and looked everywhere for reviews of good dentists. Finally found Dr. Seiden and stayed with him the entire time we were there. He has a modern practice with a great staff. Very personable. Had a number of cleanings and two fillings with him and all went very easily. He's done extensive traveling and loves talking about that and riding his bike around DC. We were sorry to leave DC (and Dr. Seiden) and now are restarting the search for a good dentist in Boston.