Abstract

Background: To systematically evaluate the clinical effectiveness of lingual frenectomy in children under five years of age, specifically regarding its impact on breastfeeding difficulties. Methods: A systematic review and meta-analysis were conducted following PRISMA guidelines. A comprehensive search of PubMed, Scopus, Web of Science, LILACS/BBO, Cochrane Library, Epistemonikos, and ProQuest identified clinical studies assessing breastfeeding performance before and after frenectomy in children with ankyloglossia. Data extraction and analysis were completed on 24 October 2024, encompassing all available evidence published up to that date. Methodological quality was appraised using an adapted NICE tool for cohort and cross-sectional studies. Results: From 2,961 records screened, 55 studies were included in the qualitative synthesis, and 6 provided sufficient data for meta-analysis. The pooled analysis indicated that frenectomy improved breastfeeding outcomes (RR 1.42; 95% CI: 1.32, 1.53). However, substantial heterogeneity was observed (I² = 74.8%). Sensitivity analysis excluding one outlier study markedly reduced heterogeneity but yielded a non-significant effect (RR = 0.99; 95% CI: 0.98–1.01), underscoring the impact of methodological variability. Subgroup analysis by sample size showed no significant effect modification. Qualitative assessment revealed notable methodological weaknesses. Selection bias was identified in 33% of studies and detection bias in 93%, primarily due to heterogeneity in diagnostic criteria and outcome measurements. Only 28.6% of studies applied validated diagnostic tools. Diagnostic methods most frequently used were the Coryllos classification (27%) and the Hazelbaker Assessment Tool for Lingual Frenulum Function (19%). Breastfeeding-related outcomes were often assessed through maternal self-reports, including nipple pain (VAS, 33%), LATCH (20%), and IBFAT (13%). These inconsistencies limited comparability across studies. Conclusions: Lingual frenectomy may enhance breastfeeding outcomes in children under five with ankyloglossia; however, the limited number of eligible studies, heterogeneity, and methodological shortcomings preclude firm clinical recommendations. Ankyloglossia can compromise breastfeeding, a critical factor for infant health and development. While frenectomy represents a potential therapeutic option, standardized diagnostic tools and evidence-based guidelines are needed to optimize patient selection and minimize both over- and under-treatment in this population. © The Author(s) 2025.