Both breastfed and bottle-fed infants have a need for comfort nursing. The only way bottle-fed infants can find this comfort is to "nurse" their bottles very slowly when allowed to lie and hold their own bottles, causing formula to sit against their teeth for long periods. Caries are more common in formula-fed infants, especially in those who have nighttime bottles at older ages. Among breastfed infants who develop nursing caries, most are those who comfort nurse for long periods during the night after teeth have developed. And among these, most are those who have frequent snacking and sugary foods or juices in their diets.
In cavity-prone families, or when any evidence of decay has been detected in an infant, night nursing and bottle practices can be gently reduced (not necessarily eliminated) once several teeth are present.
Heredity and environmental factors
Still, there will be genetic tendencies or other unknown factors that will make some children more susceptible to bacterial presence and destruction in their mouths no matter what measures are taken. Although damage to baby teeth does not affect adult teeth, a strong tendency for decay will likely carry over to adult teeth. Caries in baby teeth can serve as a warning that good preventive measures must be taken with permanent teeth.
A cavity is a small infection in the surface of a tooth that destroys the tooth material. Fresh mother's milk has many antimicrobial activities but both human and cow's milk have lactose sugar, which feeds cavity-causing bacteria when allowed to sit in the mouth. Mother’s milk has immune factors that reduce the presence of unfriendly bacteria, and laboratory tests show human milk does not encourage cavities. On the other hand, formula is definitely cavity-promoting. Formulas with sugars other than lactose are the worst. Although Streptococcus mutans bacteria is generally thought to be the chief cause of dental decay, the candida yeast that builds up on pacifiers and bottle nipples has been found to promote cavity formation to a great degree. Because of this candida and the high incidence of nursing caries from bottles or nighttime breastfeeding, dentists and thus pediatricians commonly recommend throwing out bottles and pacifiers at 12 months of age and weaning breastfed infants prematurely. But we must remember that permanent teeth are not harmed by baby teeth cavities.
Consider the whole child
Babies naturally experience hunger and need comforting during the night. Withholding response to these needs can be more harmful to a child than any risk of damage to temporary teeth, although your dentist may feel that teeth are the primary concern. While dental treatments in infants are certainly traumatic, the mere possibility of infant caries (about a 14 percent chance) is not enough of a worry that I would withhold or withdraw important feeding and comforting from any infant, especially before any such symptoms have occurred. Feeding and comforting practices can be modified when needed to protect teeth without blunt, drastic weaning measures.
Nursing mothers may be prone to cavities related to nursing (maybe these are the true "nursing caries"). Especially during the first months of breastfeeding, nursing mothers often find a need for midnight snacks. This food sitting against the teeth in a sleeping mom may cause some cavities in her teeth, which have mildly reduced calcium content (no matter how much calcium is supplemented) until after the end of lactation. Preventive measures should be taken in a cavity-prone mom.
If cavities are found
Like all other bones of the body, teeth have a potential to heal. Sometimes a small brown spot may be left even after the bacterial assault in a tooth has stopped due to diligent conscientious efforts. Xylitol is a natural fruit ingredient that promotes dental healing and can be found in special chewing gums for those who are old enough. Avocado, carrots, raspberry, strawberry, and yellow plum have all been found to contain anti-cavity ingredients. Likely many other dark-colored fruits and vegetables will be discovered to have the same qualities. There are many herbs that fight caries, such as cloves, mint, thyme and savory. In cheese, the lactose sugar is pre-digested. The milk protein left in cheese has been shown to be anti-cavity. It would be a great practice to end a meal with any of these foods or to choose them as snacks.
Twice/daily acidophilus drops help to maintain a less aggressive flora in the mouth. Good brushing, twice-daily flossing if the decay is between teeth, and some occasional scraping with a dental tool at home are valuable efforts. Never allow food or drink (besides water) to sit in the mouth at night. During night breastfeeding one can encourage some swallowing or a sip of water after nursing, or, with a determined night nurser, one could always choose not to worry about it for a while and see how quickly the decay progresses.
Baby teeth are not permanent. There is no real reason to fix them if there is no pain, unless the decay is very deep, with the potential to go into the gumline or root and cause infection beyond the hard tooth itself. If a child has mysterious health symptoms, reducing bacterial load in the mouth by drilling out cavities might help. But it's very traumatic for most toddlers, costs money, and causes various toxin exposures, so it's worth considering a "watch and wait" approach.
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