ABSTRACT Objective: The objective of this study was to evaluate the effect of the rapid palatal expansion (RPE) on the pterygoid process (PP). spheno-occipital synchondrosis (SOS) and sella turcica (ST) in the skull of a patient with transversal maxillary collapse. and identify the distribution of mechanical stresses and displacement. by finite element analysis (FEA). https://www.spidertattooz.com/Bolt-Action-San-Marco-Marines-Infantry-Section/