A scanning electron microscopical study of initial changes in human premolars teeth after orthodontic tooth movement

Abstract

scanning electron microscope was used to study the effect of orthodontic tooth movement by using a force of 50 grams on the pressure side of 2l upper left premolar
mt for 5- 75 days while the contralaterl side 14 teeth were used as a control. In order to
ruiy the morphology and occurrence of root resorptions, the organic tissue was removed
rsigg sodium hypochlorite and the denuded root surface were re—examined in the
scanning electron microscope. Initially, tissue affected by pressure was mainly located in
he marginal region and subsequently the mid- portion of the roots became generally
uri genced. The resorption process of cementum begins after 5 days as around cavities
measuring about 4u. Further resorption in cementum was characterized by measuring
small, thin—walled round lacunae which confluence into extensive, shallow resorptions
after 25 days and more