Natural Salivary Antibody Activity to Streptococcus mutans in Mexican Children

Objective: The number of Mexican American migrating to the United States is rapidly growing, and according to NHANES data, Mexican American children have a high prevalence of dental caries. Additionally, the percentage of untreated dental caries in this ethnic group is higher than in non-Hispanic blacks and non-Hispanic whites. The objective of this IRB approved pilot study was to analyze naturally occurring activity to Streptococcus mutans (SM) in saliva collected from children in Puebla, Mexico to initiate baseline information to compare with Mexican American children. Methods: 96 children aged 10 to 12 years old were recruited from 2 classes (i.e., Group A and B, respectively) in the 5th grade of a public elementary school in Puebla, Mexico. Unstimulated parotid saliva was collected using Schaefer cups, then clarified by centrifugation and frozen until analyzed by ELISA. SM specific IgA/total IgA activity for the two groups was analyzed by t-test following log transformation of the data to normalize variation. Results: Geometric mean anti-SM activity was 0.048% and 0.079%, for Group A and B, respectively (p=0.0004). Geometric mean SM counts were 4.15x10⁵ and 2.77x10⁵, for Group A and B, respectively (p=0.067). The mean DMF were 1.14 (Group A) and 1.65 (Group B) were not significantly different. There was an equal distribution of male/female and socioeconomic status in the groups. Conclusions: Although the relationship between SM antibody levels, SM counts, and dental caries experience are unclear, these findings support an association that further correlation analyses will help to delineate.

This study supported by the NIH Short Term Training Grant: T35 HL07473