O rthodontic treatment consists of such the active one that means to remove the malposition teeth aside onto a better one, and the second is the passive treatment as a retention periode means an appliance is available to defence the removing teeth. One of the retainer is the Essix made of an elastic and transparant material that covered from caninus to caninus or more over whole teeth to defence at once. The benefit of using Essix is beside of easy made, good esthetic, not disturbing to the functional activity, has simple construction but strong enough and last but not least has self cleansing ability.