Correlations between different plaque indexes and bleeding on probing: A concurrent validity study

BACKGROUND: It is stated that plaque indexes emphasizing interproximal areas or gingival margins are important when periodontal inflammation is the main focus. This cross-sectional study aimed to evaluate the concurrent validity between the following indexes: Greene & Vermillion (GV), Quigley & Hein modified by Turesky (QHT), Silness & Löe (SL), Ainamo & Bay (AB), O’Leary (OL), Deinzer (DZ), and bleeding on probing (BOP). MATERIAL AND METHODS: A sample comprising 183 individuals underwent complete periodontal examination and were divided according their periodontal status. BOP was expressed in percentages of affected sites for the entire mouth and for lingual, buccal and interproximal surfaces. Spearman correlations were calculated for each index and BOP at each area. RESULTS: Overall, correlations were moderate between all indexes and BOP at all areas, except for the OL index that showed weak correlations. The concurrent validity increased for the gingival health group, reaching strong correlations between the AB, GV, DZ indexes and BOP at the entire mouth. In the gingivitis and periodontitis groups, the concurrent validity decreased, with most correlations reaching weak or non-significant values. CONCLUSIONS: In cross-sectional evaluations, the GV, QHT, SL, AB and DZ indexes showed good validity concurrent with BOP, regardless of their specific characteristics. Key words:Bleeding on probing, concurrent validity, correlation study, periodontal diseases, dental plaque index.