Your toothbrush
You should be replacing your toothbrush every few months, once the bristles are frayed.
Pro tip: For more efficient tooth brushing, use an electric toothbrush that provides a clinically proven superior clean than a regular manual toothbrush. Our recommendation is Oral-B White Pro 1000 Power Rechargeable Electric Toothbrush because it has precisely angled bristles which are set at 16 degrees to reach deep between teeth and a 2-minute-timer that lets you know when you should switch the areas of your mouth.