Orthodontically induced osteocyte apoptosis under different force magnitudes in rats: an immunohistochemical study

We investigated the effect of different force magnitudes on osteocyte apoptosis in a model of orthodontic tooth movement. Forty‐nine male Sprague Dawley rats (7–9 wk of age) were divided into light‐ and heavy‐force groups (n = 21 each group) and a control group (n = 7). A coil spring delivered pressure (either 10–15 g or 20–25 g) to the left maxillary first molar. The rats were sacrificed 1, 3, or 5 d after placement of the appliance. Sections of the maxillary first molars were immunostained for caspase‐3. Upon force application, the number of apoptotic osteocytes significantly increased in the pressure side at 1 d and remained the same at 3 d and 5 d. However, there was no significant difference in the number of apoptotic osteocytes between the two force groups. We conclude that osteocyte apoptosis appears to increase under orthodontic loading, reaching a plateau after 1 d. However, osteocyte apoptosis seems to be independent of the magnitude of orthodontic forces tested.

Source: European Journal of Oral Sciences - August 1, 2017 Category: Dentistry Authors: Hassan E. Kassem, Iman M. Talaat, Afaf El ‐Sawa, Hanan Ismail, Abbas Zaher Tags: Original Article Source Type: research