Dental caries – a transmissible and infectious disease revisited: a position paper

Resident’s Name: Joanne Lewis Date: October 17, 2008
Article title: Dental caries – a transmissible and infectious disease revisited: a position paper
Author(s): Page W. Caufield, DDS, PhD
Journal: Pediatric Dentistry
Volume (number): 19:8
Month, Year: 1997
Major topic: the natural history of dental caries
Minor topic(s): transmission of s. mutans from mother to infant
Type of Article: Position paper
Main Purpose: To discuss the natural history of dental caries, with an emphasis on the mutans streptococci as the primary cariogenic biota.
Overview of method of research: Review and summary of research done at the author’s laboratory over the last 20 years; review of other research relating to the topic
Findings: The mutans streptococci (MS – mainly s. mutans and s. sobrinus) are principal members of a cariogenic flora, and without them, caries would be minimal or nonexistent. However, merely counting the number of MS is not sufficient to predict risk. Three concepts: 1.) Window of infectivity. Most infants acquire MS between 19 and 33 months of age (median age of 26 months). The presence of the first and second primary molars was key events in the initial acquisition of MS because they introduce fissured surfaces. Virgin molars provide a surface were MS can colonize without having to compete with other microflora. The window closes after all 20 primary teeth erupt and become colonized by other microorganisms. 2.) Fidelity of transmission (source of MS to infant). Mothers are the primary source of oral microbes to their children. When studies were done comparing the strain of MS found in the mother to the strain of MS found in her child, some interesting things were found. The fidelity of transmission between mothers and their female infants was significantly better than the fidelity of transmission between mothers and their male infants. African-American mothers transmitted MS to their infants with greater fidelity than white mothers. There was not one instance of strains of MS common to father and child. Breast-fed infants acquire MS with greater fidelity than non-breastfed infants. and 3.) Clonality – some strain of MS are more virulent than others. Strains that contain a certain plasmid (5.6 kb plasmid) are more virulent. In one study, it was found that no two isolates of MS were the same unless their hosts were related.
Key points/Summary: In the future, pediatric dentists may be using diagnostic tools such as DNA-based tests to identify particular strains of cariogenic bacteria. That information could then be used for treatment planning from a preventive point of view.
Assessment of article: It’s motivating to think about caries as a transmissible infectious disease that could potentially be cured. In a dream world, it would be really interesting to genotype the SM cultures we are collecting in the ECC study.