It is also called reverse headgear or a facemask. It is a type of removable orthodontic appliance attached to the patient’s head with a number of straps and transfers the force to the teeth to correct reverse bite problems where the top front teeth biting behind the bottom front teeth. It is usually used for 14 hours per day for an average of 6-18 months depending on the severity of the reverse bite. This is followed by another phase of fixed braces treatment. Strong scientific evidence showed that this appliance is very effective in reducing the need for more complicated treatment in the future such as jaw surgery.