This document discusses extraction in orthodontics, including the need for extraction and different extraction procedures. The main reasons for extraction include correcting arch length-tooth material discrepancies, sagittal interarch relationships, abnormal tooth size/form, and skeletal jaw malrelations. Common extraction procedures described are balancing, compensating, enforced, and Wilkinson extractions. The most frequently extracted teeth are upper and lower first premolars to relieve crowding or proclination. Other teeth may be extracted depending on factors like tooth position/quality, skeletal growth, and malocclusion type.