Abstract
Chewing efficiency was investigated in 25 children with cleft lip and/or palate in a prepubertal peried (test group; 5 isolated cleft palates,12 unilateral cleft lip and palates, and 8 bilateral cleft lip and palates) and 12 children with acceptable good occlusions (control group) based on the method devised by Manly et al (1950).
Results obtained were as follows:
1. The average chewing efficiency for the control group was 100.9% (SD=32.6).
2. Children with isolated cleft palate revealed an average chewing efficiency of 53.4% (SD = 34.3). For those with unilateral cleft lip and palate and for those with bilateral cleft lip and palate, the chewing efficien cies were 28.4% (SD=13.0) and 15.1% (SD= 6.6) on avarage, respectively. The differences of chewin g efficiency between control group and test group were statistically significant (isolated cleft palate was sig n ificant at P<0.05, unilateral and bilateral cleft lip and palate were significant at P<0.001).
3. The cumulative percentages of pulverised peanuts on 4,6 and 8 meshed screens in the unilateral and bilateral cleft lip and palate group were significantly higher (P<0.001) than those for control group.
4. In regard to those who revealed crossbites in the posterior segment in the experimental group, significant difference was not determined for the chewing efficiencies between the segments with an d without cross-bite.
5. The chewing efficiencies in the affected and non-affected sides did not differ in children with unilateral cleft lip and palates.
