Patients with dental irregularities often exhibit timid, defensive, and passive behaviors due to their low self-esteem regarding their appearance. Their appearance can significantly impact various aspects of their lives, including social interactions, job opportunities, partner selection, and personality traits, affecting their quality of life. In these persons, orthognathic surgery assumes greater importance (
29).
According to this result, the dental and oral health-related quality of life (in aesthetics, functionality, and awareness) significantly improved in patients 6 months after surgery. Based on Cohen's d and Hedges' g, the effect sizes of orthognathic surgery on patients' quality of life were found to be 0.806726 and 0.803444, respectively. Values of 0.2 to 0.5 are considered small, 0.5 to 0.8 are considered medium, and greater than 0.8 are considered significant. Based on the effect size index, the findings of this study indicate that the strength of the relationship between orthognathic surgery and quality of life in patients undergoing surgery is strong and high (r = 0.806726). Therefore, it can be concluded that 80% of the variance in the participants' quality of life change scores is due to the orthognathic surgery variable. The findings of the present study, in comparison with the results of the systematic review by Alkaabi et al., ultimately, 29 eligible studies were reviewed based on their effect size. One study indicates the significant impact of orthognathic surgery on the quality of life of these patients (
30). The results of the present study support the findings of Sen et al. (
17), dos Santos Cordeiro et al. (
31), Schaefer et al. (
32), and Johansson et al. (
33). In these studies, orthognathic surgery also significantly affected the quality of life related to oral and dental health. It seems that the improvement in quality of life after surgery is due to changes in appearance and a sense of satisfaction with life.
The theoretical basis of this study is grounded in the perspective of Steven Hayes, developer of the theory of psychological flexibility and acceptance and commitment therapy (ACT). According to this perspective, one aspect of psychological inflexibility is fusion with a real or imagined defect, body image, thought, memory, or emotion. Therefore, it seems that with orthognathic surgery and improvement in the patient's appearance, instead of fusion, the patient reaches diffusion, and consequently, other components of psychological inflexibility, including avoidance, conceptualized self, and dominance of the conceptualized past and future, are modified. The patient moves towards clarifying their life values and taking active action towards essential life values, which ultimately leads to an improved quality of life (
34).
On the other hand, according to psychological findings, improvement in body image is associated with a better sense of self-esteem and, consequently, with an increase in quality of life. The findings of the meta-analysis and systematic review (2023) support this psychological explanation (
35,
36).
However, it did not significantly impact patient social relationships. Furthermore, there was no significant effect on perfectionism, stress, anxiety, and depression among patients. In explaining and justifying these findings, it can be said that perfectionism is a relatively stable personality trait (
37). Although it is one factor that makes a person dissatisfied with their appearance and makes people volunteer for cosmetic procedures, it is resistant to change. This personality trait does not change simply with orthognathic surgery. On the other hand, the findings of the present study showed that orthognathic surgery did not have a significant effect on mental health indicators such as depression, anxiety, and stress. Perhaps one of the reasons for this lack of significant difference in the level of psychopathology indicators before and after surgery is that psychological disorders are multifactorial and cannot be improved by surgery alone, and require serious psychological treatments.
Other findings of this study reported the relationship between personality (perfectionism), psychological variables such as depression, anxiety, stress, and oral and dental-related quality of life. The dental and oral health-related quality of life maintains a significant negative relationship with depression, anxiety, and stress. As depression, anxiety, and stress levels increase, the dental and oral health-related quality of life decreases.
Additionally, a significant positive association exists between perfectionism and dental and oral health-related quality of life, wherein an increase in perfectionism is associated with an improvement in patients' dental and oral health-related quality of life. According to the literature on perfectionism, there are two distinct types of perfectionism: Positive and negative. While negative perfectionism is a personality trait associated with avoidance and procrastination, positive perfectionism is pragmatic and high-standard but requires reasonable effort to achieve the goals. Therefore, it is possible that the patients who were candidates for surgery were individuals with positive perfectionism, so this type of perfectionism was positively related to quality of life but not to psychological distress.
Comparing our findings with the results of Eslamipour's study is noteworthy. Eslamipour (
8) examined 43 patients and found that facial and orthognathic surgery significantly improves and increases the quality of life in persons with dental-facial abnormalities six months after the surgery. The most significant changes occurred in the emotional dimension. Although the results of the present study were consistent with the Eslamipour findings, the most important improvements were observed in the aesthetic dimension. The findings of our study support the explanation and conceptualization made by Miguel et al.'s study (
38), which indicates that the decision to undergo orthognathic surgery depends on its impact on each individual's beauty, function, and social relationships. It appears that these components contribute to changes in self-concept and self-esteem by altering one's attitude towards their appearance, ultimately improving the quality of life after orthognathic surgery.
Our findings share similarities and differences with those of similar studies conducted in both developed and developing countries, which are noteworthy. For example, Tuk et al. (
39) in the Netherlands demonstrated that patients' quality of life decreased immediately after the operation but improved over time. Therefore, it seems that more than 6 months must pass after the operation so that the mental health status gradually changes with the increase in the dimensions of quality of life, and depression, anxiety, and psychological distress decrease. Perhaps this is why the quality of life increased in the participants of our study after the operation, but no significant change was seen in the psychopathology variables. Duarte et al. (
40) also obtained similar results after examining the results of orthognathic surgery, which aligned with the present study's findings. It is also comparable to the findings of our study and similar studies in Eastern countries. For example, Abdullah (
41) found a significant improvement in clients' quality of life after orthognathic surgery, involving 17 patients in Saudi Arabia. Rezaei et al. (
42) reported that orthognathic surgery is significant for clients with skeletal Class III malocclusion and significantly improves their quality of life, as observed in a study of 112 patients in Kermanshah. In addition, the results of Al-Bitar's and Al-Ahmad study (
10) indicated that patients undergoing orthognathic surgery had lower levels of anxiety and PTSD symptoms. These findings differ from our study. In the present study, surgery after 6 months increased quality of life but did not affect anxiety, depression, and stress. This difference may be due to the etiology of the surgical candidates in the two groups. As mentioned earlier, trauma led to the surgery. Therefore, treatment of the effects of trauma reduced the anxiety caused by it, while in our study, psychological symptoms were associated with personality traits and were, therefore, resistant to change. In support of this explanation, we can also refer to the study by Kim (
43), which found that most clients in Korea undergo orthognathic surgery for aesthetic purposes, resulting in improvements in both beauty and functionality after the surgery. Bamashmous et al. (
44), with 70 patients, indicated that social anxiety and quality of life were improved after orthognathic surgery. Barel et al. (
45) in Brazil showed that increased awareness of orthognathic surgery methods reduces anxiety levels. In this study, we find a high and significant negative association between quality of life and anxiety severity. In addition, other studies, contrary to the findings of our research, showed that surgery can significantly reduce the symptoms of at least one of the psychological disorders, such as depression or anxiety, which we will mention, and then explain the possible reason for this difference. For example, another researchers stated in a study in France that orthognathic surgery increases the quality of life and reduces depression, but there was no effect on anxiety. However, patients who had high levels of anxiety before surgery showed less improvement in the mentioned indicators. This is while in the present study, orthognathic surgery improved the quality of life but had no significant effect on anxiety and depression. Nevertheless, we find a high and significant negative association between quality of life, stress, anxiety, depression severity, and perfectionism. Since oral health-related quality of life is inversely and significantly correlated with depression, stress, and anxiety, and surgery improves quality of life, we expected that surgery would also be effective in reducing depression and anxiety, but this was not seen in this study. It may be said that since in this study, surgery did not have a significant effect on deep personality traits such as perfectionism, despite the improvement in oral health-related quality of life, reducing symptoms of depression and anxiety requires changes in mediating variables such as dysfunctional attitudes toward oneself and others, maladaptive schemas, and personality traits such as perfectionism.
Finally, our study group shared similar age and educational backgrounds; however, we recognize that socioeconomic status influences the availability of orthognathic care, patient expectations for aesthetic improvements, and postoperative care assistance. People with higher socioeconomic status in Iran experience more financial freedom to undergo surgery and complete their follow-up care, unlike lower-income patients who encounter obstacles to accessing treatment and psychological support. Iran's collectivist society values family endorsement and community standards, which makes facial deformities more psychologically distressing and pushes people towards surgical correction for social acceptance. The sample consisted of women as the majority group, at 51.4%, which illustrates both women's growing interest in aesthetic procedures and possible variations in health-seeking patterns between genders. Future research should analyze outcomes based on socioeconomic status indicators, investigate cultural beliefs through qualitative interviews, and determine whether gender-specific support systems enhance both functional recovery and psychosocial adjustment.
The current study has yielded promising results; however, it is essential to acknowledge its multiple limitations. The study's results may lack wider applicability because they are based on data from a single center, which may not accurately represent broader populations with similar conditions. Multi-center studies would help improve external validity. The study's follow-up duration of six months might not be adequate for detecting the intervention's extended psychological and functional results. Extended follow-up periods in future research will help determine whether these treatment effects remain stable over time. Monitoring participants for at least one year or more will yield deeper insights into the intervention's lasting effects on life quality and mental health. The study evaluated quality of life and mental health exclusively through self-reported questionnaires. Although these tools receive broad usage and validation, they remain subjective in nature and vulnerable to biases from memory recall and social desirability as well as varied personal perceptions. The use of self-report measures introduces potential confounding factors which make deriving objective conclusions challenging. Upcoming research must integrate clinician-administered evaluations or physiological measurements to improve measurement precision. The study employed a pre-post design, which could potentially introduce response bias. The fact that participants knew they were being evaluated multiple times during the study might have affected their responses in both conscious and subconscious ways. Subsequent research should investigate the implementation of control groups or alternative research designs, such as randomized controlled trials, to minimize bias and strengthen causal conclusions. The census sampling method used caused selection bias, compromising sample representativeness and creating confounding variables. Future investigations should employ multi-center studies with objective evaluations, along with control groups and randomized sampling methods, to enhance the validity and applicability of research outcomes. Future research initiatives must focus on including bigger sample sizes and more diverse demographics, along with extended follow-up durations, to achieve a thorough analysis of long-term effects.
5.1. Potential Hawthorne Effect
The participants' knowledge of constant observation and evaluation may have led to enhanced self-reported results through the Hawthorne effect, where study participation alters behavior rather than producing genuine treatment effects. Our six-month interval and use of well-validated trait-based questionnaires (Depression Anxiety Stress Scales-21, Frost Multidimensional Perfectionism Scale, Orthognathic Quality of Life Questionnaire) reduce short-term reactivity, as all follow-ups occurred during routine clinical care without extra attention. However, we cannot eliminate this bias (
46). Blinded outcome assessors and objective measurements should be included in future controlled studies to further reduce observation-related effects.
5.2. Practical Implication
Our findings suggest that orthognathic patients would benefit from clinicians implementing a multidisciplinary care pathway throughout their treatment. Healthcare providers should begin with routine pre-surgical assessments for psychological risks like high perfectionism and depression/anxiety/stress symptoms, then direct those who need it to behavioral health specialists for specific treatments before surgical procedures. The care pathway requires structured follow-up appointments at 1 week, 1, 3, and 6 months postoperatively to detect complications or distress early and perform functional assessments and psychosocial evaluations. Patients should receive standardized educational materials that describe realistic aesthetic and functional results, recovery timelines, and emphasize the importance of following post-surgery regimens. Incorporate family members into counseling sessions to build social support networks that promote long-term lifestyle changes, including smoking cessation and nutritional improvements, leading to ongoing quality-of-life benefits.
5.3. Conclusions
According to the study's findings, orthognathic surgery significantly improved patients' quality of life related to dental and oral health. Still, it did not substantially affect perfectionism, depression, and anxiety symptoms 6 months after surgery. On the other hand, depression, anxiety, and stress levels were significantly associated with patients' oral and dental health-related quality of life. Therefore, orthognathic surgery and appropriate psychological interventions are recommended to increase the quality of life of these patients.