There is still controversy regarding the efficacy of functional appliances when treating malocclusion at an early age. Although a good outcome from treatment is important, the stability of the results over time becomes a major concern. This paper presents the results of three open bite cases treated with the Bimler type-A appliance in the mixed dentition. The open bite cases presented here demonstrate stability of the treatment results for more than 14 years without active retention after the active treatment period. A comparison between these cases and those performed with an elastic functional appliance, and the action of that appliance on tongue posture, are discussed. The cases presented in this paper support treating malocclusions at an early age with functional appliances. The features of the appliance chosen to treat an open bite early can be a key factor for the results and stability.