Comparison of Community Periodontal Index of Treatment Needs and Bleeding on Probing in Partial- and Full-Mouth Examinations for Assessing Children’s Gingival Status: A Cross-Sectional Study

Background: The asymptomatic progression of initial gingival inflammation in children often remains unnoticed or undiagnosed. Although full-mouth periodontal examination is considered the gold standard in diagnosing periodontal diseases, it is usually time-consuming and expensive. Therefore, the aim of this study was to assess gingival status using partial-mouth examination with the Community Periodontal Index of Treatment Needs (CPITN) and full-mouth examination with Bleeding on Probing (BOP) in the periodontal diagnosis of adolescents. Methods: This cross-sectional study was conducted in a sample of 457 Bulgarian children aged 11 to 14 years. Full-mouth examination was performed with the BOP index on all fully erupted permanent teeth, probing four gingival sites—three buccal and one oral. Partial-mouth examination was performed with CPITN, probing six representative teeth at six sites. Statistical analysis was conducted using Pearson’s chi-square test (χ2) and t-tests to compare relative proportions. Results: The BOP index identified significantly more healthy children compared to the CPITN (t = 1.90, p < 0.05). The CPITN has limitations in distinguishing between initial (BOP 10–30%) and advanced (BOP 30–60%) gingival inflammation. The comparative evaluation of the two indices by sextant showed that a healthy periodontium is most commonly observed in the posterior segments of both jaws in children, while gingival inflammation is localized predominantly in frontal areas. Conclusions: The CPITN has the advantage of providing a quick and easy method for recording gingival status in children, but it does not allow for the determination of the severity of gingival inflammation. Clinical Significance: Full-mouth examination using the BOP index is a more appropriate method for periodontal diagnosis in children, as it provides a detailed and comprehensive picture of the condition of the gingival tissues, especially when a clinical diagnosis is required to guide further treatment planning.