Brushing only isnt the only preventive measure in caries removal..you should do it with proper technique.
Before brushing floss each and every tooth properly, than use soft bristles brush and fluoride containing toothpaste for atleast 5-7 minutes in to and fro motion. At last do mouthwash rinses. With this if you only brush ones than it is more than sufficient. Moreover, what you eat also affects your oral health. Avoid eating candy's and other sticky products.
Also i would recommend you to visit a dentist and get the filling done as caries is irreversible...for more info on dental hygiene visit the link...http://www.identalhub.com/dental-clean-your-teeth-correctly-521.aspx