The Pleasant Nighttime appliance is part of the removable “Activator Family” that includes the Bionator and the Orthodontic Corrector. All three removable appliances are used to correct Class II cases. The Pleasant Nighttime appliance was a predecessor to the Bionator. Specifically, it provides upper and lower expansion while rounding-out the arch.

The Pleasant Nighttime appliance is normally worn at night. During the day most doctors recommend wearing an upper expansion version with an inclined plane called a Pleasant Daytime appliance.