Objective: To assess dental arch dimensions (width, depth) in mixed dentition in a sample of Kurdish orthodontic patients.
Methods: A sample of 58 dental casts (28 class I, 30 class II division 1 malocclusions) from 8 years and two months to 10 years and nine months were collected. Measurement of arch dimensions was taken, including width and depth. Differences between males and females and between class I and class II division 2 malocclusion were tested using independent t-test.
Results: With gender pooled, class I group has larger UC, UE, U6, LE, L6 width than class II group, whereas class II group has larger LC width than class I group with no significant difference. The class II group has larger arch depth for maxillary measurements than the class I group, with no significant difference. While the class I group has larger arch depth for mandibular measurements than the class II group, with no significant difference except for LC. In gender dimorphism, class I group, all arch width measurements, females have a larger width than males except L6; all differences were no significant. While in all arch depth measurements, males have larger depth than females. In the class II group, all measurements of width and depth were larger in males than females, the difference in UE and U6 were significant.
Conclusions: Class I malocclusion has larger width and depth than class II division 1 malocclusion, except in the maxillary depth of class II division 1 malocclusion. Males had larger arch dimensions than females.