This article describes the use of composite inclined planes called Planas Direct Tracks
(PDTs) to correct more complex cases of crossbite in the deciduous dentition.
Prof. Pedro Planas of Spain initially developed PDTs,1 and Simoes11 adapted them for early prevention of anterior or posterior crossbite.
PDTs should be used in the deciduous dentition only, as they cover the occlusal surfaces of the molars, resulting in a flat posterior occlusion until the molars are exfoliated.