Global variations in eruption chronology of permanent teeth: A systematic review and meta-analysis

Population-based variations have been reported in permanent teeth eruption but only sparse literature exists on the same. A systematic review and meta-analysis were performed to assess the global variations in eruption chronology of permanent teeth in children and adolescents and the role of sexes, jaws and classes of socio-economic status (SES) on timing of eruption was explored.

The protocol for the systematic review was registered in PROSPERO. An extensive search of PubMed, EMBASE, Google Scholar, EBSCO, Cochrane library, and anthropology databases was carried out until April 2023. Additionally, grey literature search and hand-searching of relevant key journals was done.

Overall, 3797 cross-sectional and longitudinal studies were retrieved from multiple databases. A total of 939, 191 participants were included from 80 studies of which, 41 were carried out in Asia, 26 in Europe, 5 in Africa, 4 in North America, and 4 in Oceania. The mandibular first molar eruption was found to be as early as 4.09 years while the maxillary second molar erupted as late as 13.45 years. Using a random effects model, 28 forest plots were generated. Meta-regression interpreted tooth eruption to be earlier in females and in the mandible.

The findings of this study show that the ages of permanent teeth eruption was advanced in the European population followed by Africa and Asia.