Oral health attitudes and clinical periodontal status in Turkish undergraduate dental students: discordance between self-reported behaviour and clinical findings — a cross- sectional study

Technical Summary: Oral Health Attitudes and Clinical Periodontal Status in Turkish Undergraduate Dental Students

Problem Statement
While self-reported behavioral questionnaires are standard tools for assessing oral health attitudes among dental students, there is a scarcity of research that simultaneously evaluates these subjective reports against objective clinical periodontal status within the same cohort. Existing literature often relies exclusively on questionnaire data, leaving the concordance between self-perceived attitudes and actual clinical findings unverified. Furthermore, the interplay between academic progression (preclinical vs. clinical years) and gender in modifying these oral health outcomes has rarely been examined through a formal two-way interaction analysis. This study addresses the gap in understanding whether self-reported behavioral instruments accurately reflect the clinical periodontal reality of dental students.

Methodology
This cross-sectional study was conducted at the Istanbul University Faculty of Dentistry during the 2018–2019 academic year. The cohort consisted of 264 undergraduate dental students, stratified into preclinical (Years 1–2, n=134) and clinical (Years 3–5, n=130) groups.

• Data Collection:
  • Self-Report: Participants completed the validated modified Turkish Hiroshima University–Dental Behavioral Inventory (HU-DBI), a 27-item instrument assessing oral health attitudes and behaviors. Scores range from 0 to 20, with higher scores indicating more positive attitudes.
  • Clinical Examination: 255 students underwent full-mouth clinical examinations by calibrated periodontists. Measurements included the Plaque Index (PI), Gingival Index (GI), and Probing Pocket Depth (PPD) recorded at six sites per tooth (excluding third molars).
• Analytical Approach: Due to the anonymous nature of the questionnaires, HU-DBI and clinical data were analyzed independently at the group level rather than linked at the individual level. Non-parametric statistical methods were employed due to data non-normality. Group comparisons utilized the Mann–Whitney U test, while the Scheirer–Ray–Hare extension of the Kruskal–Wallis test was used to assess main effects and interactions for academic year and gender.

Key Results
The study revealed a significant divergence between self-reported attitudes and clinical findings, particularly regarding gender patterns across academic years.

• HU-DBI Scores: Clinical students demonstrated significantly higher HU-DBI scores than preclinical students (mean difference 1.05; p < 0.001), indicating improved self-reported attitudes with training. However, no significant gender difference or year×gender interaction was found in HU-DBI scores.
• Clinical Indices (PI and GI): Academic year was strongly associated with improved clinical status (lower PI and GI). Crucially, a significant academic year × gender interaction was observed for both PI and GI, a pattern absent in the questionnaire data.
  • Preclinical Group: Females exhibited better plaque control and gingival health than males.
  • Clinical Group: This pattern reversed. Male students achieved substantially greater reductions in PI (88.2% reduction) and GI (74.1% reduction) compared to females (55.2% and 20.6% reductions, respectively).
  • Periodontal Health Status: 96.4% of clinical male students attained periodontal health, compared to only 2.9% of clinical female students. Conversely, all severe gingivitis cases were confined to preclinical male students.
• Correlations: While the overall Spearman correlation between PI and GI was strong (rs = 0.851), subgroup analysis showed near-zero, non-significant correlations in three of the four subgroups, suggesting that pooled correlations masked subgroup heterogeneity.

Significance and Claims
The authors conclude that clinical training is associated with improvements in both self-reported attitudes and clinical periodontal status, yet these improvements operate through distinct mechanisms. The study claims that:

1. Discordance Exists: Self-reported behavioral instruments (HU-DBI) and clinical periodontal indices provide complementary but non-interchangeable information. The HU-DBI failed to capture the significant gender-divergent patterns observed in clinical outcomes.
2. Limitations of Self-Report: Relying solely on questionnaires may provide an incomplete picture of students' periodontal health, particularly when clinical outcomes vary significantly across subgroups.
3. Educational Implications: The findings suggest that academic progression does not automatically translate into optimal clinical periodontal health for all students. The authors propose that integrating periodic clinical periodontal monitoring with standardized attitudinal assessments could offer a more comprehensive approach to evaluating dental education programs.
4. Hypothesis on Gender Reversal: The authors speculate that the reversal of gender differences in clinical status may be due to regression to the mean (males starting with worse baseline health), differential motivation in clinical settings, or hormonal factors influencing gingival inflammation in females, though the latter remains unconfirmed due to the lack of hormonal data collection.

The paper maintains a modest stance, acknowledging that the cross-sectional design prevents causal inferences regarding training effects and that the anonymous data collection precludes individual-level concordance analysis. It positions the study as a necessary step in highlighting the limitations of self-reporting in dental education research.