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Updated: Jun 13, 2026

Oral Health Assessment by Lay Personnel for Older Adults
Published on: February 2, 2020
Prevalence and severity of gingivitis in American adults
Yiming Li1, Sean Lee, Philippe Hujoel
1Center for Dental Research, Loma Linda University School of Dentistry, 24876 Taylor Street, Loma Linda, CA 92350, USA. yli@llu.edu
Purpose:
To investigate prevalence and severity of gingivitis in representative American adults.
Methods:
Subjects (1,000) in Loma Linda, California; Seattle, Washington; and Boston, Massachusetts were examined for Löe-Silness Gingivitis Index (GI). Mann-Whitney rank sum test was used to determine significances in the GI between genders. The data among study sites and races were compared using the Kruskal-Wallis one-way ANOVA on ranks. The correlation of the GI and age was examined by the Spearman rank order correlation. Age differences among three sites were analyzed using the one-way ANOVA.
Results:
The race composition of the subjects (mean age 37.9) approximated to the 2004 U.S. Census data. The overall average GI was 1.055. Only 6.1% of subjects showed mean GI<0.50; most (93.9%) were > or = 0.50, with 55.7% > or = 1.00. There was a significant correlation (P<0.001) between the age and GI. The males' GI was significantly higher (P<0.001) than the females'; African-Americans showed a significantly higher GI (P<0.05) than other races except for the Native-Americans.
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