Relationship between short lingual frenulum and malocclusion. A multicentre study.

OBJECTIVE: Ankyloglossia is characterized by an abnormally short lingual frenulum, which impairs tongue movement. Ankyloglossia has been related to craniofacial growth disturbances and dental malocclusion. But even though there is a clear biological plausibility for this hypothesis, available evidence is scarce.

METHODS: A case-control design was followed. Patients between 4 and 14 years old were routinely screened for short lingual frenulum and recruited from the pediatric Otolaryngology consultation of 3 Spanish tertiary referral hospitals. Lingual frenulum was assessed with the Marchesan system. A cohort of cases with short lingual frenulum and a cohort of healthy controls matched for sex and age were included. Both cases and controls had pictures of occlusion. Occlusion was evaluated by an expert in orthodontics, blinded for the frenulum assessment.

RESULTS: A total of 100 participants were included, 70 males and 30 females. The proportion of malocclusion in the short lingual frenulum group was 48%, while it was 24% in the normal frenulum group. The odds ratio of malocclusion for the short lingual frenulum patients was 2.92 (CI 95% 1.15-7.56). The difference was statistically significant (p=.012). This difference was significant for patients with class III occlusion (p=.029). There was no difference for patients with class II (p=.317).

CONCLUSIONS: This work supports the hypothesis that relates class III malocclusion with a short lingual frenulum.