Primary tooth eruption linked to a salivary stress marker in young children

The saliva of young children linked the pace of eruption to stress biology

Parents usually accept without question that teeth erupt in their own time, but developmental medicine has for years regarded the pace of growth as a possible trace of early stress exposures. The team led by Kopycka-Kedzierawski asked the question directly: is the number of erupted tooth surfaces in young children associated with measurable markers of stress biology?

A diverse group of children aged one to three years was followed, all of them caries-free at baseline. Alongside the course of eruption itself, socioeconomic and psychosocial oral health factors, oral microbiology and salivary stress markers were recorded — at baseline, then every six months over two years.

The finding centres on cortisol. A blunted cortisol response to a laboratory stressor was strongly associated with the number of erupted tooth surfaces recorded at the first examination (estimate −6.51; SE 1.90; 95% CI −10.23 to −2.79; p < 0.001), and that after adjustment for other factors. The same association held in the longitudinal analyses across the two years of follow-up. The authors read this as new evidence that a marker of stress biology is associated with tooth eruption in early childhood, and that behind the pace of eruption stand developmental and biological influences of wider reach, which at the same time shape the child's oral health.

Limitations

This is an observational cohort: an association was shown, not causation. The direction of the effect and the clinical size of the difference require confirmation in larger samples, and the study abstract leaves room for different readings of the sign of the estimate.

For your practice

• Markedly early or markedly late eruption is not a diagnosis, but it is an occasion for a conversation about family circumstances, not only about the eruption calendar.
• The first examination of a caries-free child is the best opportunity to record a baseline; the number of erupted tooth surfaces is a simple and useful measure.
• Early stress and oral health share the same socioeconomic determinants — if you recognise them in the history, step up the preventive protocol instead of waiting for the first lesion.