Foods to be avoided include foods high in sugar, sticky foods, and hard-to-eat foods. Based on common sense, there are certain types of foods you need to avoid. As often observed by dentists, sticky foods can get lodged between wires and brackets. It is wise to reduce your intake of sugary foods, because they create the potential for tooth decay. Hard foods can break or damage wires and brackets. Other things to avoid include biting foreign objects, pencil chewing, pen chewing, and nail biting.