The protraction facemasks to treat Class III malocclusion in children are unaesthetic and uncomfortable, cause skin irritations and prevent compliance with the therapy. SuperPowerMe develops a customised facemask considering different aspects of children's experience: ergonomics, aesthetics, social acceptance and motivating factors. The project employs 3D modelling techniques to model the facemask on child’s anatomy, 3D printing with biocompatible materials, and customized design to reach a proper balance between ergonomics, functionality and aesthetics. Thanks to embedded sensors and a mobile app, the therapy is monitored based on wear time and it is connected with gamification strategy to promote children’s compliance. SuperPowerMe is a co-design project involving different stakeholders (children, parents, orthodontists, designers, engineers, psychologists) to iteratively design the customisation process, experiment with different materials and ideate the gamification strategy.