Investigation of Type D Personality, Somatization Disorder and Perceived Social Support in Patients With Temporomandibular Joint Disorders

This research was designed as a prospective cross-sectional study conducted between February 2025 and June 2025 in the Otorhinolaryngology outpatient clinic of Gaziantep City Hospital, Turkey. The study included two groups: patients diagnosed with temporomandibular joint disorders and healthy control participants matched for age and gender. All participants were between 18 and 65 years of age, literate, cognitively intact, and voluntarily agreed to participate. Ethical approval was granted by the institutional ethics committee, and written informed consent was obtained from all individuals before enrollment.

Data collection involved face-to-face interviews using standardized self-report questionnaires. The following instruments were used:

1. **Mandibular Function Impairment Questionnaire:** This instrument includes 17 questions that evaluate functional problems of the jaw during daily activities. Each question is scored on a five-point scale, and higher total scores indicate greater impairment in jaw function.
2. **Hospital Anxiety and Depression Scale:** This tool consists of 14 questions that measure symptoms of anxiety and depression. It has two parts, each containing seven questions. Each section produces a total score between zero and twenty-one, where higher values represent greater symptom severity.
3. **Type D Personality Scale:** This scale contains fourteen statements divided into two categories: negative emotions and social inhibition. Each statement is rated on a five-point scale from zero to four. A score of ten or more on both categories indicates the presence of Type D personality traits.
4. **Somatization Scale:** This questionnaire includes thirty-three true or false statements that identify the presence of unexplained physical symptoms. Some statements are reverse coded. Higher total scores show more frequent or severe somatic complaints.
5. **Multidimensional Scale of Perceived Social Support:** This twelve-question scale measures perceived emotional and practical support from three sources: family, friends, and a significant other. Each item is rated on a seven-point scale. Higher scores represent stronger perceived social support.

In addition to these scales, sociodemographic data such as age, sex, marital status, education, occupation, and income were recorded. Exclusion criteria included the presence of severe psychiatric disorders, neurological disease, or cognitive impairment that could interfere with understanding or completing the questionnaires.

All collected data were analyzed using appropriate statistical methods. Distribution normality was assessed, and comparisons between the two groups were performed using suitable parametric or non-parametric tests. Associations among the measured psychological and functional parameters were examined through correlation analyses.