Dental floss is the best way to clean interdental surfaces and surfaces above the above the gum line. There is a special method of using dental floss:
take 45-60 cm of floss and wind the bigger part of it round the long finger or the forefinger;
wind the rest of the floss round the finger of the other hand. You will wind the used floss round this finger;
clutch the floss with the thumb and the forefinger but leave a small of the floss - about 3 cm - free (stretch the floss properly);
perform careful sawing movements pulling the floss through the teeth (be careful not to hurt the sensitive gums);
when you reach the gum line roll the floss in the shape of the letter "C" so that it would cover the tooth (clean the surface between the tooth and the gum);
take the floss up from the gum to clean the side surface of the tooth (to remove dental deposit make sure that the floss fits the tooth closely);
do not forget to clean the backsides of the teeth.
