The relationship of oral malodor to gingivitis: cross-sectional epidemiology and longitudinal randomized clinical trial evidence

This research assessed the relationship between oral malodor, measured by halimetry and organoleptic grading, and gingivitis as measured by number of gingival bleeding sites (GBS). Two complementary clinical studies were examined. The first was a cross-sectional trial evaluating the association between volatile sulfur compounds measured by halimetry and organoleptic scores (0-5 scale). The second study was a randomized, 2-treatment, parallel group trial evaluating oral malodor using a 1-9 hedonic scale between a control group and an oral hygiene regimen over 8 d. In both trials, GBS were derived from Löe-Silness gingival index scores. Multiple types of regression analyses were used to assess the relationship in both studies. In study 1, 980 participants were included in the analysis with a mean age of 39.6 years (range 18-89 years). 75% were female. Mean (SD) baseline values were 14.18 (23.22) for number of GBS, 188 ppb (66.08) for halimeter score, and 3.6 (1.01) for organoleptic score. There was a significant (<i>p</i>= 0.003) association between halimeter score and number of GBS, driven by participants defined with localized/generalized gingivitis (≥10% GBS). Generalized gingivitis (>30% GBS), localized gingivitis (10%-30% GBS) and generally healthy participants (<10% GBS) had mean halimeter scores of 223.29 ppb, 191.19 ppb, and 183.52 ppb, respectively. Similar results were observed comparing organoleptic scores by gingivitis case type. In study 2, 60 participants were included in the analysis with mean age of 36.7 years (range 18-60); 68% were female. Mean (SD) baseline values were 80.92 (24.508) for number of GBS and 8.29 (0.709) for hedonic score. A statistically significant (<i>p</i>< 0.001) correlation between hedonic score reduction (change from baseline) and reduction in number of GBS (change from baseline) was observed,<i>r</i>= 0.73. This research shows a relationship between GBS and oral malodor, as assessed by either halimetry or organoleptic/hedonic scoring.