Orthognathic surgery might have a surprising impact on how we perceive the world

A recent study published in Frontiers in Psychology has found that individuals who undergo jaw surgery for jaw deformities may experience improvements in self-perception and a heightened sensitivity to emotional aspects of objects around them. The study suggests that these changes in facial appearance might not only enhance physical attractiveness but also influence cognitive functions. These results highlight the surprising mental and emotional impacts of facial surgery, which go beyond physical health and aesthetics.

Orthognathic surgery, a procedure often used to correct facial deformities associated with jaw structure, has long been recognized for its positive impact on quality of life. By addressing functional and appearance-related issues, this type of surgery improves patients’ ability to chew and speak while also helping alleviate psychological distress linked to self-image. Many patients report a boost in confidence and general quality of life following surgery, but researchers have mostly focused on how these procedures affect physical health and broad emotional states.

The question of whether these surgeries specifically change cognitive functions—such as how patients perceive themselves or respond emotionally to the outside world—has largely gone unexplored. This study aimed to close this gap, investigating how changes in facial appearance might influence self-evaluation and reactions to emotional cues in the surrounding environment.

“While the goal of orthognathic surgery for jaw deformities is to improve facial appearance, it is also intended to eliminate psychological distress. However, this has rarely been verified,” explained study author Motoyasu Honma, a junior associate professor at the Showa University School of Medicine in Tokyo. “Our interest was in how improvements in facial appearance benefit the psychological aspects of patients, and behind this interest was the hypothesis that the effects of orthognathic surgery extend beyond appearance to include individual self-evaluation and mental health.”

The research team gathered two groups of participants: 22 patients who underwent orthognathic surgery and a control group of 30 healthy, age- and sex-matched individuals. The patients in the surgery group, ranging in age from 18 to 39, underwent specific types of jaw surgeries, such as the bilateral sagittal split osteotomy, with or without the Le Fort I osteotomy, between September 2020 and June 2021. All patients completed several stages of assessment at various intervals: three months before surgery, one month before surgery, and one month post-surgery.

For their evaluations, patients rated how they felt about their own face and body, assessing both emotional response and preference using a visual scale. In addition, patients reviewed 30 different images, some designed to evoke positive, negative, or neutral emotions, and rated how much they liked or disliked each image. Patients’ anxiety levels were also measured using the State–Trait Anxiety Inventory, a tool designed to measure anxiety both as a stable personality trait and as a temporary response to specific situations. This allowed the researchers to assess how patients’ emotional reactions, self-assessments, and anxiety levels shifted over time.

The researchers found that patients viewed their facial appearance more favorably after the surgery, while their opinions of their body image stayed relatively constant. This change in facial self-evaluation confirms that patients felt better about their appearance specifically because of the facial improvements from surgery rather than an overall shift in self-image.

In addition to the changes in self-perception, patients also showed heightened sensitivity to emotional images after their surgery. When patients viewed images with positive or negative emotional content, they reacted more intensely than they did before the surgery, while their responses to neutral images remained unaffected. This suggests that the surgery did not simply heighten emotional sensitivity across the board; instead, it specifically impacted the way patients responded to content with emotional significance.

“What I found surprising was that the results showed that the negative images were perceived more negatively, while the positive images were perceived more positively, rather than all the images being evaluated positively,” Honma told PsyPost. “I interpreted this as probably being due to the fact that the participants’ sensitivity to emotional images had increased.”

Another interesting finding was the correlation between improved self-ratings and emotional sensitivity. Patients who rated their facial appearance more positively after surgery were also the ones who showed the strongest emotional responses to the positive and negative images. This connection implies that as patients’ views of their own appearance improved, they became more emotionally receptive to the world around them. However, this heightened sensitivity was not linked to a reduction in anxiety, suggesting that the improved emotional responsiveness was a unique benefit of the surgery itself rather than a byproduct of reduced stress.

“This study has presented the benefits of facial improvement for patients in terms of changes in cognitive function,” Honma said. “These benefits may be a new aspect effect of plastic surgery, and may benefit the entire beauty industry. For the general public, similar benefits may also be occurring in everyday makeup behavior.”

While this study provides valuable insight into the cognitive and emotional effects of facial surgery, it is important to consider its limitations. One limitation is the relatively small sample size. Increasing the sample size in future studies would help confirm and expand upon these findings. Additionally, while the study examined the impact of surgery on self-perception and emotional sensitivity, it did not explore how surgery might affect other aspects of mental health, such as social anxiety or sleep quality. Further research in these areas could help clarify the potential of orthognathic surgery to reduce broader psychological symptoms.

“Although this study focused on changes in anxiety, it is also possible that PTSD and sleep disorders are also involved, and it is hoped that these will also be investigated,” Honma said. “In addition, with regard to cognitive science indicators, it is thought that it is important to investigate the possibility of changes in taste and respiratory function due to improvement in the jaw joint. We hope to achieve the treatment goal eliminating psychological disorders in patients with jaw deformities through a multifaceted investigation.”

“The current experimental data showed that facial surgery also has psychological benefits, but this is not intended to be an easy recommendation for facial surgery,” the researcher added.

The study, “Changes in facial appearance alter one’s sensitivity not only to the self but also to the outside world,” was authored by Motoyasu Honma, Sayaka Yoshiba, Saya Miyamoto, Nanae Himi, Shugo Haga, Sumire Ogura, Koutaro Maki, Yuri Masaoka, Masahiko Izumizaki, and Tatsuo Shirota.