The timing of tooth eruption in preterm children: A systematic review

Background Preterm birth has been reported to affect normal physiological growth and development of preterm-delivered children. Whether preterm birth affects primary and permanent tooth eruption, is not yet determined. Aims To identify whether preterm birth affects tooth eruption by reviewing scientific literature. Methods MEDLINE, EMBASE, Cochrane library and reference lists of included studies were screened from January 1980 to November 2020. The study designs included both interventional and observational studies analysing peculiarities of tooth eruption in premature infants with no congenital syndromes. Risk of bias was assessed using NIH Quality Assessment tool for cohort, cross-sectional studies. Results Twelve articles were selected for data extraction after exclusion of 1709 irrelevant studies. Primary teeth eruption time in preterm children was delayed up to two months taking account of chronological age only. In most studies, after changing the age from chronological to corrected, the eruption of primary teeth was still delayed, but the difference was negligible. Catch-up growth occurs in 18 months and the difference in primary teeth eruption time remains insignificant. Very low birth weight and nonbreastfeeding were associated with delayed primary teeth eruption. One study found earlier eruption of first permanent molars and incisors, while other two stated lagging maturation of permanent teeth up to the age of nine years. The quality of evidence provided by the studies was low. Conclusion Considering chronological age, primary teeth eruption time in preterm children was delayed and related to very low birth weight and non-breastfeeding. Data on eruption of permanent teeth were inconsistent; more detailed research is need.