Mother-to-child transmission of Streptococcus mutans: a systematic review and meta-analysis

A systematic review was performed with the aim of determining whether there is scientific evidence of the transmission of Streptococcus mutans from mother to child.

The eligibility criteria, based on the PECO strategy, were the following: observational human studies whose subjects were mother and child pairs (P) contaminated by S. mutans (E); comparison according to the presence or absence of S. mutans (C); and whether there is transmission (O). The qualitative analysis was performed by assessing the risk of bias of the included studies, while quantitative synthesis was performed through comprehensive Meta-Analysis software (p<0.05).

Two reviewers performed the database search of studies published between January 1950 and May 2014. The strategy included observational studies that assessed the vertical transmission of S. mutans from mothers to children through analyzing genetic strains.

It was found 166 non-duplicated studies. However, after reviewing the articles in full and applying the eligibility criteria, 36 papers were selected for qualitative analysis and 19 for quantitative analysis. The cumulative meta-analysis demonstrated vertical transmission of S. mutans from mother to child (p<0.001).

The present systematic review and meta-analysis demonstrated evidence of vertical transmission of S. mutans from mother to child because there was an association between S. mutans n mothers and their respective children.

The knowledge of the S. mutans strains is important because the virulence of the microorganisms is varied; also, the virulence affects the dental caries evolution rate, being more or less aggressive.