Correlation study between ankyloglossia and mandibular development and lower anterior crowding

To study the association between ankyloglossia and sagittal mandibular development impairment as well as lower anterior dental crowding, providing a reference for clinical practice.

This study was approved by the hospital's Medical Ethics Committee. A total of 100 patients aged 7-13 years were enrolled from January 2024 to January 2025, comprising 50 patients with ankyloglossia (case group) and 50 individuals with a healthy lingual frenulum (normal group). Clinical examination was performed to assess lingual frenulum length, Kotlow classification, and the simplified Hazelbaker assessment tool for lingual frenulum function (HATLFF) score. Cephalometric radiographs were used to measure the A-point-nasion-B-point (ANB) angle, sella-nasion-B-point (SNB) angle, and mandibular total length (condylion-gnathion [Co-Gn]). Dental cast analysis was conducted to evaluate lower anterior teeth crowding. Data were compared between the two groups. Pearson correlation analysis was used to examine the relationships between the lingual frenulum length, simplified HATLFF score, and cephalometric/dental cast parameters (ANB, SNB, Co-Gn, lower anterior crowding). The diagnostic value of ankyloglossia for mandibular development and lower anterior crowding was analyzed using receiver operating characteristic (ROC) curves.

Ankyloglossia was significantly associated with mandibular development and lower anterior crowding (P<0.05). The case group showed significantly lower values for the lingual frenulum length, simplified HATLFF score, SNB angle, and Co-Gn, while the ANB angle and lower anterior crowding index were significantly higher compared to the normal group (P<0.05). The lingual frenulum length and simplified HATLFF score were negatively correlated with the ANB angle and lower anterior crowding index, and positively correlated with the SNB angle and Co-Gn (P<0.05). ROC curve analysis indicated that the area under the curve (AUC) for the simplified HATLFF score, and ankyloglossia in predicting mandibular development deficiency and lower anterior crowding was greater than 0.700, demonstrating good diagnostic value.

A significant correlation exists between ankyloglossia and both mandibular development deficiency and lower anterior crowding.