The diagnosis of Stage III generalized periodontitis was established based on the presence of one or more of the following clinical and radiographic findings: a probing pocket depth (PD) of ≥ 6 mm and/or clinical attachment loss (CAL) of ≥ 5 mm; radiographic evidence of bone loss extending to the middle or apical third of the root; a history of tooth loss due to periodontitis involving four or fewer teeth; CAL of ≥ 5 mm affecting 30% or more of the dentition; vertical bone loss of ≥ 3 mm; Class II or III furcation involvement; and the presence of moderate ridge defects.

The diagnosis of Stage IV generalized periodontitis was based on more severe manifestations, including CAL of ≥ 5 mm and radiographic bone loss reaching the middle or apical third of the root. Additionally, patients exhibited tooth loss due to periodontitis affecting five or more teeth, masticatory dysfunction, occlusal dysfunction, severe ridge defects, and/or signs of secondary occlusal trauma.

The ISS consists of 29 items and is a self-report scale assessing internalized stigma. ISS includes 5 subscales: 1. Alienation (6 items), 2. Confirmation of Stereotypes (7 items), 3. Perceived Discrimination (5 items), 4. Social Withdrawal (6 items), 5. Resistance to Stigmatization (5 items). ISS is a Likert-type scale calculated as 'strongly disagree' (1 point), 'disagree' (2 points), 'agree' (3 points), 'strongly agree' (4 points). The items of the 'Resistance to stigmatization' subscale are reverse scored. High scores on this scale indicate how aggressive the person's internalized stigma is negatively. ISS has been adapted for many diseases other than mental illnesses in our country and its validity and reliability have been demonstrated.

Tooth loss due to periodontitis refers to the extraction or spontaneous exfoliation of a tooth as a direct consequence of the progressive destruction of the tooth-supporting structures, including the periodontal ligament, alveolar bone, and connective tissue attachment. This destruction results from chronic inflammation and tissue breakdown caused by periodontal pathogens. Teeth are considered lost due to periodontitis when mobility, severe attachment loss, and bone resorption render them non-functional, painful, or unsalvageable despite periodontal therapy.

Internalized Stigma of Mental Illness Scale assessment was performed in patients with tooth loss due to periodontitis.Internalized Stigma of Mental Illness Scale is a Likert-type scale calculated as 'strongly disagree' (1 point), 'disagree' (2 points), 'agree' (3 points), 'strongly agree' (4 points).High scores on this scale indicate how aggressive the person's internalized stigma is negatively.

Sociodemographic data such as age, gender, marital status, education level, income level, smoking status, presence of systemic diseases, reason for referral, and frequency of tooth brushing were recorded.Internalized Stigma of Mental Illness Scale is a Likert-type scale calculated as 'strongly disagree' (1 point), 'disagree' (2 points), 'agree' (3 points), 'strongly agree' (4 points).High scores on this scale indicate how aggressive the person's internalized stigma is negatively.

These measurements were taken at specific sites around each tooth via a Williams periodontal probe.

The Plaque Index (PI), as described by Silness and Löe, is used to assess the thickness of plaque at the gingival area.Without using disclosing agents, the presence of plaque is assessed visually and by gently passing the probe along the gingival margin. Each surface is scored on a scale from 0 to 3:

Score 0: No plaque.

Score 1: A film of plaque adhering to the free gingival margin and adjacent area of the tooth, detectable only by running a probe across the tooth surface.

Score 2: Moderate accumulation of soft deposits within the gingival pocket or on the tooth and gingival margin, visible to the naked eye.

Score 3: Abundance of soft matter within the gingival pocket and/or on the tooth and gingival margin.