The validity and reproducibility of an oral rating index as a measurement of gingival health care and oral hygiene level in adults

The purpose of this study was to investigate the validity and reproducibility of an oral rating index (ORI) as a conceptual measurement of “gingival health care” level in adults. The study was conducted on 163 patients who received medical examinations and attended for dental checkups at a hospital. The score of the ORI was recorded as excellent (+2), good (+1), questionable (0), poor (−1) or very poor (−2). The validity of the ORI was investigated by comparing it with: Jackson's gingivitis index (GI); Greene & Vermillion's debris index (DI) and calculus index (CI); probing pocket depth (PPD); and percentage of bleeding on probing (%BOP). The intra‐ and inter‐examiner reproducibility of the ORI was assessed on a flat screen using patients' color transparencies of the mouth. The ORI had significantly negative correlations with the GI, DI, CI, and PPD ( p <0.001). The κ values were 0.604–0.672 for intra‐examiner reproducibility, and 0.441–0.449 for inter‐examiner reproducibility. The present study suggests that the ORI has moderate to good intra‐examiner and inter‐examiner reproducibility. Mouth examination using the ORI appears to provide useful information that will enable a dental professional or health educator to make sensible decisions on the type and level of oral health instruction according to adults' gingival health care level.