An Experimental Study Of The Effects Of Endodontical Treatment On Orthodontic Movement In Cat Cuspids

Objective:To evaluate the effectiveness of orthodontic forces in moving endodontically treated teeth and the risk of apical resorption which may happen during the Orthodontic movement, an animal model was established. Methods :Under general anesthesia, root canal therapy was performed on the mandibular canines on one side of 16 adult cats. Tipping movement of the canines was induced with an orthodontic spring (100 to 120 g). Eight weeks later, tooth movement was assessed from pre- and posttreatment mandibular casts, as well as the measurement of root lengths in both radiographs and histological sections. Results: Results showed that endodontically treated teeth and vital teeth moved similar distances when subjected to the same forces (p> 0.05). And endodontically treated teeth had greater loss of cementum after tooth movement than vital teeth (p< 0.05), but without significant differences in radiographic root length (p > 0.05). Conclusions:The conclusion is that, endodontically treated teeth mayperform orthodontic movement as readily as vital teeth when subjected to the same orthodontic forces under the conditions of the study .However, Endodontically treated teeth have the relatively more root resorption than vital teeth during the orthodontic movement which may not be detected form the radiography.