Knowledge of Periodontitis and Its Relation to Periodontal Health

Periodontal disease (PD) is defined as a chronic, multifactorial inflammatory disease, characterized by the progressive destruction of the supporting tissues of the teeth. Its development mainly depends on two essential factors: the accumulation of bacterial biofilm and the host's immunoinflammatory response to pathogenic microorganisms. However, other factors also contribute to the onset and progression of the disease, both intraoral and extraoral, including poor oral hygiene, inadequate or harmful dietary habits, and various systemic factors.

The host response to bacterial invasion triggers a series of local inflammatory processes that manifest clinically through signs such as edema, erythema, and gingival bleeding. These manifestations not only affect the oral cavity but may also significantly influence overall systemic health, as PD has been associated with multiple systemic diseases, including diabetes mellitus, cardiovascular diseases, obesity, and pregnancy-related complications. Several studies have shown that the relationship between PD and these conditions is bidirectional: periodontal disease may exacerbate or predispose individuals to these pathologies, while, in turn, these conditions may worsen the progression of PD.

At a global level, PD is recognized as the sixth most prevalent disease worldwide, highlighting the importance of timely and appropriate diagnosis and treatment. In this regard, the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP) have proposed an updated classification of periodontal diseases, aimed at enabling more individualized diagnosis and more precise treatment planning. Among the most relevant changes are the redefinition of diagnostic criteria for gingivitis based on objective clinical signs, and the introduction of the concepts of staging and grading, which take into account disease severity, extent, and rate of progression.

Furthermore, this classification acknowledges that certain systemic conditions-such as diabetes mellitus and smoking-modify the grade of the disease, directly influencing treatment planning and the clinical prognosis of each patient.

Regarding therapeutic management, the literature emphasizes that prevention is the most effective measure to reduce the high prevalence of PD. Prevention is based on risk factor control and early detection of initial signs and symptoms. Adequate preventive strategies help avoid frequent complications such as dental sensitivity, halitosis, tooth mobility, and tooth loss, as well as reduce the impact of PD on various systemic diseases.

Healthcare professionals play an essential role in this preventive process, as they are often the first to identify gingival alterations or early signs of inflammation. Therefore, maintaining up-to-date knowledge of periodontal health is fundamental to improving early detection, patient education, and interdisciplinary intervention.

Within this context, the present study proposes the development of an assessment instrument to evaluate knowledge of periodontal health. This instrument focuses on three main aspects:

Identification of the clinical signs of the disease. Recognition of etiological and risk factors. Understanding of the relationship between PD and systemic diseases. The general objective of the study is to determine the level of knowledge regarding periodontal health among health sciences students through the application of a concise, specific, and effective questionnaire to measure their understanding of PD and its interrelationship with systemic health, as well as to evaluate whether the level of knowledge is associated with students' periodontal health status and/or their daily oral hygiene practices, with the aim of implementing educational measures in dentistry across different health sciences degree programs.

2\. Background and Current State of the Topic Periodontitis is a chronic inflammatory disease that leads to the loss of dental supporting tissues and may negatively affect general health. Knowledge and oral hygiene practices play a key role in its prevention. Comparing Dentistry students, who receive more extensive training in oral health, with Psychology students allows for the analysis of whether knowledge levels are related to the observed prevalence of periodontal disease, thereby helping to guide interdisciplinary educational interventions.

3\. Objectives

Primary objective:

To evaluate the level of knowledge regarding periodontal disease among Dentistry and Psychology students.

To quantify the level of knowledge, attitudes, and practices (KAP) in each group.

Secondary objectives:

To analyze the prevalence of gingivitis and/or periodontal disease in each cohort.

To compare prevalence between both cohorts and estimate the association after adjusting for covariates (age, sex, smoking status, socioeconomic level, medication use, toothbrushing frequency, dental floss use, and relevant systemic diagnoses).

To propose educational recommendations based on the study findings.

Study Design An observational, cross-sectional, analytical, and comparative study will be conducted to evaluate the association between the level of knowledge about periodontitis and the prevalence of periodontal disease in two cohorts: final-year undergraduate students in Dentistry and Psychology at the Universitat Internacional de Catalunya (UIC).

Population and Sample

1. Target population University students enrolled in the Dentistry and Psychology degree programs at the Universitat Internacional de Catalunya during the current academic year. 2. Sampling A randomized and stratified sampling method will be used, considering the two degree programs as strata. A total of 60 participants is expected to be included (30 per group), although this number may be adjusted depending on availability and the population size of each cohort. 3. Inclusion criteria Students enrolled in the Dentistry or Psychology degree programs at UIC. Age ≥ 18 years. Voluntary agreement to participate through signed informed consent. 4. Exclusion criteria Periodontal treatment within the previous 6 months. Presence of uncontrolled systemic diseases that may affect periodontal status (e.g., uncontrolled diabetes mellitus, immunodeficiencies).

Pregnancy or breastfeeding, if considered relevant according to the Ethics Committee due to potential hormonal alterations affecting periodontal health.

Withdrawal or refusal of informed consent at any stage of the study. Study Phases and Data Collection

Data collection will be carried out in two main phases:

Phase 1: KAP Questionnaire Administration

A Knowledge, Attitudes, and Practices (KAP) questionnaire, previously adapted and validated in Spanish, will be administered to assess:

Knowledge regarding periodontitis (etiology, clinical signs, and consequences). Attitudes toward oral health and preventive behaviors. Oral hygiene practices and frequency of dental visits. The questionnaire will be self-administered in digital or paper format, depending on logistical feasibility. It will be completed on the same day as the periodontal examination, in the university dental clinic under the supervision of the principal examiner (PDI) and secondary examiner (IV), in order to minimize potential bias.

Knowledge-related items will be quantitatively scored and subsequently categorized into three levels: low, medium, and high.

Phase 2: Clinical Periodontal Examination Each participant will undergo a comprehensive periodontal examination performed by a qualified professional holding the European Board in Periodontology certification (PDI), under standardized biosafety conditions.

A calibrated millimeter periodontal probe will be used to record the following variables through a full-mouth periodontal chart:

Plaque Index:

Assesses the presence or absence of dental plaque on each disclosed tooth surface.

Plaque Index (%)

= Number of surfaces with plaque Total number of examined surfaces

× 100 Plaque Index (%)= Total number of examined surfaces Number of surfaces with plaque * 100

Bleeding on probing:

Presence or absence of bleeding following probing. 0 = no bleeding 1 = bleeding Bleeding percentage = Number of bleeding sites Total number of examined sites

× 100 Bleeding percentage= Total number of examined sites Number of bleeding sites

×100

Probing depth (PD):

Measurement of periodontal pocket depth in millimeters using a calibrated probe.

• Bleeding on probing [Time frame: March 2026 to June 2026]
• Plaque index [Time frame: March 2026 to June 2026]
• Recession [Time frame: March 2026 to June 2026]
• Probing depth [Time frame: March 2026 to June 2026]
• Lost of attachment [Time frame: March 2026 to June 2026]