Brushing and Flossing once a day:

Anyone with this regimen gets a B- to a C grade for oral hygiene. The best time to floss in a 24 hour period is at night before brushing teeth. The correct way to floss is in an up and down motion and NOT to pull the floss back and forth in a sawing motion. The main purpose to flossing is to clean the sides of the teeth by removing the plaque and debris that may have collected during the course of the day. At the same time the floss is used up and down, this motion actually helps to massage the gums. If the floss is pulled back and forth in a sawing motion, this will actually do more damage to the gums and will have little effect on cleaning the plaque or debris off the surface of teeth.

For brushing, the correct motion is to brush from the teeth towards the gums in a rotating motion. The back and forth sawing motion that most people have will cause gum recession and tooth abrasion leading to sensitivity and possible Pulpectomy(root canal) . So start rotating the toothbrush and stop sawing at your gums and you have years of healthy gums and teeth

Flossing and brushing twice to three times daily:

Anyone with this regimen gets a B to an A grade for oral hygiene. For some who want to keep their teeth and gums at optimal health, along with regular professional dental care, flossing and brushing 2 to 3 times daily will definitely result in excellent oral hygiene. The correct form of brushing and flossing are listed under "brushing and flossing once a day".