[Radiographic cephalometry assessment of the linear and angular parameters on cranial base in children with skeletal class III].

Background/aim: In malocclusion of skeletal class III, mandible is located in front of maxilla in sagital plain, which is manifested by a lower value of the sagital inter-jaw angle than in skeletal class I, where the jaw sagital relation is normal. Apart from the deformities on mandible and/or maxilla, in skeletal class III deformities are also frequent on the cranial base. The aim of this research was to find the differences in the parameter values on the cranial base among the children with skeletal class III and the children with skeletal class I in the period of mixed dentition.

Methods: After clinical examination and orthopan-tomography, profile radiography of the head was analyzed in 60 examinees, aged from 6-12 years. The examinees were divided into two groups: group 1--the children with skeletal class III; group 2--the children with skeletal class I. Both linear and angular parameters on the cranial base were measured, as well as the angles of maxillary and mandible prognatism and the angle of sagital inter-jaw relation. The level of difference in the parameter values between the groups was estimated and the degree of correlation of the main angle of the cranial base with the angles of sagital position of the jaws in each of the two groups was established.

Results: A significant difference between the groups was found only in the average values of the angles of maxillary prognatism and sagital inter-jaw relation. In the group 1, the main angle of the cranial base was in a significant correlation with the angles of sagital positions of the jaws, while in the group 2, such significance was not found.

Conclusion: There were no significant differences in the parameter values on the cranial base between the groups. There was a significant correlation of the main angle of the cranial base with the angles of sagital position of the jaws in the group 1 only.