Worldwide prevalence of natal and neonatal teeth: Systematic review and meta-analysis

Background: Identifying the presence of teeth in newborns is important as it may require immediate care. This study aimed to determine the worldwide prevalence of natal and neonatal teeth.

Type of studies reviewed: Six electronic databases and the gray literature were searched on February 23, 2023 to identify observational studies reporting the prevalence of natal or neonatal teeth. Studies assuming natal and neonatal teeth as identical terms or not reporting prevalence indicators were excluded. The methodological quality of the studies was assessed using the Joanna Briggs Institute checklist for studies reporting prevalence data. The worldwide prevalence of natal and neonatal teeth was estimated via proportion meta-analysis using a β-binomial model. Heterogeneity across studies was explored via subgroup analyses and meta-regression.

Results: None of the 23 included studies fulfilled all items of the methodological quality checklist. The worldwide prevalence of natal teeth was 34.55 (95% CI, 20.12 to 59.26) per 10,000, and the prevalence of neonatal teeth was 4.52 (95% CI, 2.59 to 17.91) per 10,000. Subgroup analysis by continent showed that the prevalence of natal teeth ranged from 11.26 (95% CI, 7.58 to 16.61) per 10,000 in Asia through 75.32 (95% CI, 51.11 to 99.86) per 10,000 in North America, and the prevalence of neonatal teeth ranged from 3.52 (95% CI, 1.73 to 7.06) per 10,000 in Europe through 6.01 (95% CI, 2.25 to 16.60) per 10,000 in South America. Meta-regression did not find a statistically significant association between prevalence rates and year of publication or sample size.

Practical implications: Approximately 1 in 289 newborns had natal teeth and 1 in 2,212 had neonatal teeth. Although this is not a high prevalence, professionals must be alert to identify these conditions, which often require immediate care.