John C. Chao, DDS

Research Associate Professor, University at Buffalo, SUNY
Adjunct Assistant Professor, Ostrow School of Dentistry, USC

(626) 308-9104

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John C. Chao, D.D.S., M.A.G.D
Anxiety Management,
Behavior Science,
Faculty, USC School of Dentistry

Cavity Causing Bacteria Transmitted From Mother to Child

It may not be entirely your fault that you have a lot of cavities. Mothers are the primary source of cavity causing bacteria in infants, according to UDA Action, the Utah Dental Association. These bacteria (mutans streptococcus, e.g.) colonizes the mouth of the infant between the middle of the second year to the end of the third year of life. During this “window of infectivity” colonization will occur even though few or no teeth have erupted yet. It has also been shown by studies that the higher the mother’s level of cavity causing bacteria is, the more percentage of children become infected. The bacteria will settle in the mouth permanently, and contribute to development of dental decay throughout the life of the patient. Bacteria is an indispensable link to the formation of dental decay because they convert sugar to acid, which then demineralize the dental enamel. Sufficient demineralization leads to breakdown of the enamel, which then exposes the soft organic structure underneath to chemical and bacterial attack. Eventually this process leads to infection of the dental nerve and consequent toothaches.

This new information regarding the “window of infectivity” is good news, because now it is possible to break the chain of infection, rather than wait to treat the cavities after they have developed. Since the primary source of cavity causing bacteria is the mother, it is especially important to lower the germ count in the mother during the critical infectious period. This is first of all accomplished by the mother maintaining a high level of dental hygiene at home. Thorough brushing and flossing, two or three times a day, is especially recommended. Since the back part of the tongue is a major source of bacteria, it would be helpful to use a tongue scraper for cleaning the tongue on a daily basis. Naturally, all cavities, big and small, should be filled so that bacteria can be deprived of hospitable habitats. Regular visits to the dental office will allow the dentist to evaluate effectiveness of dental hygiene habits, help the patient refine oral hygiene skills, apply fluoride, and fill any new cavities or replace any broken down fillings. The dentist may also prescribe anti-bacterial to lower the germ count, and fluoride rinses to fortify dental enamel against acidic demineralization.

Adult-to-infant transmission can be minimized without limiting normal nurturing activities. Utensils should be thoroughly cleaned and washed before they are used for the infant, and should not be shared. This general rule of hygiene prevents unnecessary exposure of the infant to infectious disease of all kinds, not just cavity causing bacteria. For instance, you may want to question the common practice of pre-tasting the food on the spoon before feeding it to the baby. Perhaps tasting the food with another spoon will do just as well. These precautionary practices should not damper in any way natural expressions of affection.

Adult-to-infant transmission can be minimized without limiting normal nurturing activities. Utensils should be thoroughly cleaned and washed before they are used for the infant, and should not be shared. This general rule of hygiene prevents unnecessary exposure of the infant to infectious disease of all kinds, not just cavity causing bacteria. For instance, you may want to question the common practice of pre-tasting the food on the spoon before feeding it to the baby. Perhaps tasting the food with another spoon will do just as well. These precautionary practices should not damper in any way natural expressions of affection.

Incidentally, be careful not to create “baby bottle syndrome,” a condition where the baby has severe cavities in the front teeth that is caused by giving the baby a milk bottle while going to sleep. Milk or sweetened fluid will lead to corrosion of the enamel if exposure is for a prolonged period of time. Baby bottle syndrome is often treated with either extensive “pulpotomies” (baby root canals) and crowns or extractions. Either way the baby is subjected to avoidable treatment. It is generally advisable to use oral or intravenous sedation to avoid traumatizing the baby.

Transmission of dental bacteria can also be minimized by parents cleaning the baby’s mouth with ultra-soft brushes or a soft, damp cloth, even before teeth have erupted. This will also tend to lower the germ count and retard the colonization process. When teeth have erupted, brushing with an ultra-soft brush is recommended.

It is now recommended that by one and half years of age, you should consult your dentist regarding dental care for your baby. Feel free to discuss the above described topics so that you can give your baby a great start in having healthy teeth and a great smile for a lifetime.


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