Use of the antibiotic amoxicillin during infancy appears to be linked to tooth enamel defects in permanent teeth, according to a study in the October issue of Archives of Pediatrics & Adolescent Medicine.
Amoxicillin is one of the most commonly used antibiotics among pediatric patients, mainly for treating otitis media infection and inflammation of the middle ear. Some evidence suggests that amoxicillin use could be associated with dental enamel defects. Even a small effect on dental enamel could have a significant effect on the public’s dental health because of the drug’s widespread use, researchers suggested.
Dr. Liang Hong, University of Iowa, Iowa City, and colleagues assessed the association between dental fluorosis and amoxicillin use during early childhood. (Dr. Hong now is with the Department of Dental Public Health and Behavioral Science, University of Missouri-Kansas City.) The researchers analyzed data from the Iowa Fluoride Study, a prospective study investigating fluoride exposures, biological and behavioral factors, and children’s dental health. They followed 579 participants from birth to 32 months, using questionnaires every three to four months to gather data about fluoride intake and amoxicillin use.
"The results show that amoxicillin use during early infancy seems to be linked to dental fluorosis on both permanent first molars and maxillary central incisors," the researchers reported. "Duration of amoxicillin use was related to the number of early-erupting permanent teeth with fluorosis."
By the age of 1 year, three-fourths of the subjects had used amoxicillin. By age 32 months, 91 percent had used amoxicillin. "Overall, 24 percent had fluorosis on both maxillary central incisors," the researchers reported.
Amoxicillin use between the ages of 3 and 6 months doubled the risk of dental fluorosis. "The significantly elevated risk for dental fluorosis associated with amoxicillin use during early infancy was found at all levels of statistical analyses, even after controlling for other potential risk factors, such as fluoride intake, otitis media infections, and breast-feeding," wrote the researchers.
The authors emphasized that additional laboratory and clinical studies—including controlled animal studies with specified amoxicillin dosages, chemical analysis and histologic examination of affected teeth, and epidemiologic studies—are needed to confirm the results.
"The findings suggest that amoxicillin use in infancy could carry some heretofore undocumented risk to the developing teeth," the researchers concluded. "While the results of this one study do not warrant recommendations to cease use of amoxicillin early in life, they do further highlight the need to use antibiotics judiciously, particularly during infancy."
This study was supported by grants from the National Institutes of Health.
