Seeing is not always believing when it comes to replacing toothbrushes, especially for the Cybersonic toothbrush. You should be following the American Dental Association's recommendation to make a replacement every three months, no matter how the head looks. Even if it appears intact, it may still be worn, especially when the bristles have performed at such high speed for so long. If you continue using it beyond three months, not only will cleaning become less effective, but you could even begin to jeopardize enamel and gums. If you do see fraying ends, you have waited too long.
Do not undermine the investment you made when you first purchased your Cybersonic, and order replacement brushes today to consolidate your dental gains. Also, put it on your calendar for another three months hence. Through Dental-Mart, you will always order from the comfort of home, and at discount prices.