Resident Research Review using digitized models and 3-D computer-aided design software. The main conclusion was that expansion across the canines and first permanent molars was almost similar; while the palate was symmetric before expansion, it became asymmetric after expansion in the middle halves. The effect of serial extraction in terms of dental tipping and changes in occlusal curves was part of a 2015 study by Dr. Esther Feldman.2 Mandibular dental casts from a group of serial extraction patients, conventional extraction patients, and controls were measured and analyzed with 3-D CAD software. Using a novel approach of measuring occlusal curves with a variation of Monson's sphere, Dr. Feldman was able to demonstrate the changes that occur in occlusal curves from physiologic drift after serial extraction to the end of fixed orthodontic treatment. The study found that serial extractions produced steeper occlusal curves and distal tipping of the incisors and canines after drift, but that the tipping was uprighted and most occlusal curve deepening corrected after completion of comprehensive fixed treatment. Palatal surface area divided into six sections using 3-D CAD software Palatal volume divided into six sections using 3-D CAD software 28 PCSO Bulletin Spring 2018