Maximum mouth opening in patients with cleft lip and palate or craniofacial anomalies compared with non-affected controls: A cross-sectional study

Background: There are limited published data on maximum mouth opening (MMO) for children with cleft lip or palate (CLP) or craniofacial anomalies (CFA). Aim: To report MMO of patients with CLP or CFA compared with non-affected controls. Design: Retrospective cross-sectional review of electronic medical and dental records. Patients with CLP or CFA with recorded MMO, height, and weight were included and compared with a non-affected control individuals seen during orthodontic screening. Outcome measures included MMO, recorded in millimeters of inter-incisal distance, age, height, weight, and sex. Results: Patients with CLP or CFA (n = 376) were matched by age and body mass standardized index (BMIz) to the non-affected pool (n = 376). The affected group had a MMO of 43.14 mm (+/- 7.1 mm) compared with the control group MMO of 48.01 mm (+/- 7.6 mm) with a statistically significant difference of -4.86 mm (p < .0001). Specifically, MMO of the unilateral cleft group is 4.26 mm smaller than that of non-affected controls (p < .0001). MMO of the bilateral cleft group is 3.65 mm smaller than that of non-affected controls (p = 0.0063). Conclusions: MMO for patients with CLP was significantly smaller as compared to non-affected controls. This study helps establish MMO values for children with CLP and CFA.