Bite force of children with repaired unilateral and bilateral cleft lip and palate

• No differences of bite force values were found among control and any of the cleft groups.
• There was a significant difference between CL and UCLP/BCLP bite forces.
• There was a significant difference between the anterior and posterior bite forces.
• There was correlation between bite force and an increase in age.
• No differences were found in values of bite force between genders.

ObjectiveTo assess the bite force (BF) of children with repaired cleft lip and palate (CLP).DesignChildren aged 6–12 years, with and without CLP, were divided into the following 5 groups: (1) control group (CON): 34 children without CLP (17 female, 17 male, mean age 8.2 ± 1.4); (2) cleft lip group (CL): 31 children with cleft lip involving the pre-maxilla (15 female, 16 male, mean age 9.7± 1.3); (3) unilateral CLP group (UCLP): 36 children with complete unilateral CLP (11 female, 25 male, mean age 9.4± 1.6); (4) bilateral CLP group (BCLP): 32 children with complete bilateral CLP (11 female, 21 male, mean age 9.5± 1.7); and 5) cleft palate group (CP): 17 children with complete cleft palate (9 female, 8 male, mean age 9.4± 1.6). Briefly, in this clinical trial, BF was assessed before alveolar bone grafting with a gnathodynamometer (IDDK, Kratos, Cotia, SP, Brazil). For CON, BCLP, CL and CP groups, BF was obtained in the anterior and posterior region of the maxilla. For the UCLP group, BF was assessed in the anterior and posterior regions of both segments. Differences among groups were evaluated by ANOVA test, and Tukey’s test was used to assess any correlations among variables (P < 0.05).ResultsUnexpectedly, no differences of BF were observed among CON and any of the cleft groups. However, a stronger BF was observed in the CL group when compared to the UCLP and BCLP groups. Next, no differences were observed between the cleft side and the noncleft side in the UCLP group. Lastly, in all groups, BFs from the anterior region of the maxilla were less when compared to the posterior regions.ConclusionThe BF of children with CLP is no different from children without CLP.