Published Online: Dec 14, 2023
Page range: 113 - 118
Received: Apr 01, 2009
Accepted: Feb 01, 2010
DOI: https://doi.org/10.2478/aoj-2010-0019
© 2010 Mohammad S.A. Akhoundi et al., published by Sciendo
This work is licensed under the Creative Commons Attribution 4.0 International License.
Objectives
To investigate the effect of morphine as an exogenous opioid on orthodontic tooth movement. Naltrexone will be used as an opioid antagonist to confirm the results.
Methods
Forty rats were randomly divided into four equal groups. The first group received no injection; the second group received daily injections of morphine; the third group received daily naltrexone-morphine injections and the fourth group daily injections of naltrexone-normal saline. The left first maxillary molar in each rat was tipped mesially with a NiTi closed coil spring. The rats were sacrificed after 14 days and the maxillae fixed, sectioned serially and examined histologically.
Results
The greatest amount of tooth movement occurred in the Control group and the least amount of tooth movement in the Morphine group. Tooth movement in the Morphine group was significantly different from the other three groups (
Conclusions
Morphine reduced orthodontic tooth movement in rats. This effect was reversed by the opioid antagonist, naltrexone, which had no effect on tooth movement.