AIM:Physical health especially oral and dental health can play a leading role in individuals’ mental health status. Therefore, determining the relationship between orthodontics, mental health, and body image can provide solutions for the development of treatment services and provision of greater accessibility of communities to them.METHODS:The present study was natural experimental research conducted to determine the relationship between orthodontic treatment, mental health, and body image. To conduct this research, individuals referring to orthodontic clinics in the city of Kermanshah and meeting the inclusion criteria in the study were selected using convenience sampling method and then they were assessed before and after undergoing orthodontics via the standardised Goldberg’s General Health Questionnaire (GHQ) and Multidimensional Body-Self Relations Questionnaire (MBSRQ).RESULTS:The mean scores of mental health problems in the study participants reduced and such a difference calculated by Wilcoxon signed-rank test with a 95% confidence level was significant (P = 0.001). Moreover, all the subscales of GHQ in the study participants showed a significant decrease after orthodontics compared to the stage before that (P < 0.05). The mean score of MBSRQ before orthodontics was equal to 171.78 and this value reached 172.51 after that, indicating individuals’ increased scores and their high levels of satisfaction with their body image. Nevertheless, the given difference was trivial, and it was not statistically significant (P = 0.751).CONCLUSIONS:The results of the present study showed that orthodontic treatment could significantly increase mental health status in the clients and also improve multidimensional attitudes towards body image.