Welcome to Midway Dental Laboratory website, we are always ready for your needs of low price and high quality twin block appliance made in China and China twin block appliance. The Twin Block appliance is used to help a receded jaw grow forward and skinny or narrow jaws grow wider to help save all permanent teeth. Doctor may recommend a Twin Block for the following cases; *An overbite (buck teeth), usually caused by the lower jaw not growing out enough. *Crowded teeth, most frequently caused by the jaw not growing wide enough. http://www.dentallabs-china.com