Dental implant treatment is an increasingly used method in oral and dental health in recent years. Thanks to dental implants, patients regain the functional part of their oral and dental health that they have lost permanently. Thanks to dental implant treatment, important gains are provided in terms of both the quality of life and aesthetic appearance of the patients, especially in nutrition. ^{1 – 3} For this reason, patients are using more and more implant options every day and thus regain their oral and dental health.

Another issue where oral and dental health is important is nutrition. Nutrition begins in the mouth and is activated by the grinding of solid foods by the teeth. Therefore, oral and dental health is of great importance, especially in solid food intake. However, in studies on oral health, there are studies reporting that nutritional disorders are seen in individuals due to problems such as dental caries or tissue in the mouth. ^{4 – 6} The common point of these studies is that there is a relationship between oral and dental health and eating disorders and those eating disorders affect both physically and psychologically.

Eating disorders are not only related to oral and dental health in general, but also have psychological roots. In the absence of a physical problem, individuals’ eating disorders are related to their psychological state and mental health. ^{7 – 10} Based on the cognitive side of every mental health issue, it is possible to state that the personality structures of individuals are also related to eating disorders. Therefore, personality types, which are indicators of personality structure, have a significant effect on eating disorders, as well as other cognitive factors.

Although eating disorders are examined according to various variables and personality structure or mental health parameters in the literature, there are not enough studies related to eating disorders and oral health. Therefore, in this study, it was aimed to examine the relationships between personality types, eating disorders and pain perception levels of patients before and after implantation.

In total, 248 patients were eligible for the research between June 2023 and August 2023, and 223 of them were respondents. ²⁶ Before implant, voluntary method was used for participation. Similarly, patients were asked to participate after implant by voluntary method. For gender distribution, 49.8% of participants were female and 50.2% were male. According to age distribution, 31.1% had 25 and under, 32.0% had 26-35, 36.9% had 36 and over ages. 61.9% of patients were working. 73.1% had normal, 23.3% had overweight and 3.6 had obese BMI level. 12.1% had eating disorder in the family, 3.6% had implant history, 22.0% had oral and maxillofacial surgery history, 19.7% had dentist fear and 83.4% had regular oral care ( Table 1).

Difference analysis results showed that extroversion and neuroticism levels of patients were significantly higher after implant (p<0.05). Pain, eating disorder and other personality type differences between before and after implant were statistically insignificant (p>0.05) ( Table 2).

Before implant, pain level was positively correlated with eating disorder (r=0.190; p<0.01) and negatively correlated with self-control (r=-0.169; p<0.01). After implant, pain level was negatively correlated with neuroticism (r=-0.140; p<0.05) and openness to experience (r=-0.136; p<0.05) ( Table 3).

Before implant, eating disorder level was positively correlated with pain (r=0.190; p<0.01); negatively correlated with extroversion (r=-0.187; p<0.01) and self-control (r=-0.178; p<0.01). After implant, eating disorder level was negatively correlated with extroversion (r=-0.237; p<0.01), self-control (r=-0.151; p<0.05) and neuroticism (r=-0.187; p<0.01) ( Table 3).

Generalized Linear (Logit) Model analysis results showed that only extroversion personality type level had significant and negative effect on eating disorder after implant at multivariate level (B=-0.43; p<0.01) ( Table 4). Before Generalized Linear (Logit) Model, correlation between demographic and baseline characteristics of patients were also analyzed. Since their correlations were insignificant (p<0.05), they were not included in the regression model.

In this study, the relationship between the personality types of individuals before and after implantation with pain and eating disorders was examined. For this purpose, the effects of personality types on eating disorders were analyzed before and after implantation on 223 patients, and both unidimensional and multidimensional analyzes of factors that may affect eating disorders were performed.

Although implant applications are very important applications for oral and dental health today, clinical studies and research generally focus on concrete properties of implants such as biological properties, osseointegration, and permanence. ^{14 – 18} Studies on the relationship between eating disorders and personality structures of individuals after dental implants are quite limited. However, the relationship between oral and dental health and eating disorders has been the subject of many studies, and it can be stated that there is both a physical and psychological relationship between oral health and eating disorders. Therefore, it can be argued that personality types that affect the psychological structures of individuals are also effective on eating disorders and pain perception.

In studies on oral and dental health and eating disorders in the literature, eating disorders are also observed in people with impaired oral health. ^{19 – 22} Patterson Norrie et al. ⁵ reported in their study that individuals with oral health problems have eating disorders. In another study, Brandt et al. ²¹ reported that the relationship between individuals’ oral health and eating disorders was significant in terms of care, and those with eating disorders were obsessed with oral health. In our study, the differences between pre- and post-implant pain levels and eating disorder levels were not statistically significant. This may be related to the fact that implant applications are now much more effective, in a shorter time, and that patients have a high level of trust in both the surgeon and the institution. Thanks to the physician and institution informing the patient at a sufficient level, the patient is informed about what they will live and as a result, he has less anxiety. This situation positively affects the mental well-being of the patient. Therefore, an increase in the level of eating disorder and pain may not have been observed after the implant. The fact that the study was single-centered may also have an effect on this result. Research findings can be further deepened with larger samples and multicenter studies.

Studies on personality types and the characters of individuals report that the character tends to remain unchanged in general. However, possible changes require trauma, unusual events, or prolonged exposure. On the other hand, personality types, on the other hand, change more easily than the character, while they show the attitude that people take according to the event or situation. ^{23 – 25} In our study, a statistically significant increase was observed in extraversion and neuroticism levels in patients compared to pre-implantation. However, the difference between other personality types before and after implant was not statistically significant. It is possible to state that the symptomatic personality type scale has an effect on this difference. The Five Factor Personality Scale shows the degrees of these personality types, not the exact personality types of individuals. For this reason, it can be stated that post-implantation individuals do not turn into extroverted and neurotic individuals, only their weight on these personality types increases. Another possible reason for this result is that implant application is a traumatizing phenomenon to some extent. Although today, implant applications are very successful and with minimum pain, as a result, an invasive procedure is performed on individuals with implants. This situation can be partially evaluated as trauma.

In our study, the meaning and positive effect of pain on pre-implant eating disorder is an expected situation that shows the reliability of the data of the research scales. In addition, extroversion and self-control before implant have a decreasing effect on eating disorders. This situation is also significant in terms of its relationship with mental well-being, especially in terms of self-control. The fact that extroverts are more social and social individuals have a higher level of mental well-being supports this situation.

After the implant, extraversion, self-control and neuroticism have a decreasing effect on eating disorder. However, this effect, which is significant in one dimension, gives a result in which only the level of extraversion is significant in multivariate analysis. In other words, when all personality types, pain and personal characteristics are evaluated together, eating disorders are less common in extroverted individuals. This finding shows that as the level of extraversion of individuals increases, the level of post-implant eating disorder development will be lower, and the reverse is also true. In other words, more introverted individuals will be more likely to have an eating disorder.

The most important limitation of the study is that it was conducted as a single center and the demographic characteristics of the patients were close to each other. More comprehensive findings on the effect of implant application, personality types and pain on eating disorders can be obtained in multicenter studies. Most importantly, since the level of informing patients will differ in different institutions, it may be possible to see the effect of psychological effects and personality structures more clearly. However, the process of getting permission from different institutions in the field of health and collecting data includes very serious and tiring processes.

Another important limitation of the study is the lack of more original and specific measurement tools for the field of oral and dental health. Today, although scales such as fear of the dentist, trust in the doctor, and fear of tooth extraction are being developed, these are the scales that are mostly associated with children’s fear of the dentist. There is a need for more comprehensive and site-specific scales for adults.

The most important contribution of the research to the literature is that it is a pioneering study in terms of its subject. Studies and studies in the literature mostly focus on biological data related to implants. This research proposes to focus on psychological factors, which are also important in the field of dental implants. In this respect, the research can be shown among the pioneering studies in the field.

Another contribution of the research to the literature is that, with a simple session to be given to extroverted and introverted individuals after the implant, it may be possible to pre-treat or prevent eating disorders that may develop in these individuals and may be much more difficult to compensate in the future. In this respect, the research gives useful results in terms of clinical applications and original results in terms of preventive medicine.

According to the results of the research, it is possible to prevent eating disorders that are likely to develop after dental implants by increasing the degree of extraversion of individuals or by giving short and effective sessions to introverted individuals. Although it is not absolute that every individual with low extraversion will develop an eating disorder, eating disorders can be prevented it, even infrequently, with partially cost-effective eating disorder informative sessions in a large population. This situation can make a significant contribution both in terms of individuals’ quality of life, public resources and public health, and oral and dental health.