In a recently released issue of Pediatrics, Dr. Dharini Ravindra and colleagues from The Royal Children’s Hospital Melbourne Australia conducted a systematic review (10.1542/peds.2023-061350) to answer the question of whether antibiotic exposure prior to age 8 years results in poorer dental health, as measured by dental caries, tooth staining, and developmental defects of enamel (defects of known etiology such as fluorosis were excluded). Only studies using validated measures of caries and enamel defects were included; since there is no validated tool to measure staining, studies with any described method were included. The authors used standard methods for the systematic review and followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines.
The authors screened 756 articles and found 34 that were eligible: 18 studied tetracycline or tetracycline-like antibiotics, 7 studied amoxicillin, and 9 did not specify the antibiotic. Studies investigating older formulations of tetracycline, published 1960-1980, all had a high risk of bias, with the exception of one. However, these studies found staining associated with tetracycline use, and although not surprising, these data underline guidance to avoid tetracycline in children under 8 years. The 5 studies on newer tetracycline class agents (doxycycline and minocycline), published 1998-2017, found no staining (or caries or enamel defects) associated with use, which aligns with newer AAP Red Book Guidance to permit doxycycline use for up to 21 days at all ages. I learned that the change from tetracycline to doxycycline removes the hydroxyl group at C-6, which essentially halves the calcium binding capability of the compound, preventing ion complexes that cause staining. While any mention of chemistry is a bit fraught for me (I was not a chemistry major to put it kindly!), this really nice information “gift” clearly explains the study results.
Read on to learn about amoxicillin and other antibiotics – studies showed both positive and negative results with no clear attribution of either amoxicillin or other antibiotics on dental caries or enamel defects. The authors walk us through the evidence, including study flaws and strengths, and explain dental outcome measures (new to me) such as tooth color shade guides and the Developmental Defects of Enamel (DDE) index. Since all included studies were retrospective, the authors also emphasize that prospective and well-designed studies are needed to answer the research questions addressed in this review. I found this article a lot of fun to read, and it made me think once more about the importance of antibiotic stewardship!
