UPDATE: today was my appointment with dr. Kwatra, he was so friendly and professional. I felt very comfortable during the cleaning. I would definitely visit him again and I would recommend this clinic to everyone.UPDATE: The office called me to arrange another appointment - free of charge - promising satisfaction and that doctor Kwatra himself should do the cleaning this time. I would call this EXCELLENT customer service.The cleaning process took less than 10 min and I checked my teeth when I went back home to find all the stains on the back of my teeth exactly as it was before.