Signature Sports Premium Type 3 Dentist 2Go Mouthguard Teeth Shield Teen Green This professional and competition level mouthguard features a full profile, precision controlled thicknesses, design replicates an impression taken by a Dentist from which a standard dentally prescribed mouthguard is made. Type 3 Dentist 2Go is a recommended choice for competition level athletes seeking a balance of price, features and custom fit. This makes the Type 3 Signature Dentist 2Go mouthguard a quality item which is the closest retail product in the world today to the handmade, custom fitted/prescribed dentist mouthguard. Sizing is best approximated using your age and an estimation of your average dentition (mouth) size. As a guide use the below suggestions for deciding which size is right for you. Typically, males have larger dentitions then women. Particularly throughout youth and teenage years. Adults with smaller than average dentitions or strong gag reflexes are encouraged to consider teen sizes for comfort.