Abstract
Aim: To evaluate the effect of cranial base parameters on mandibular parameters in class II division 1 malocclusion in three dimensions. Materials and Methods: The sample consists of 103 students age range between (18–24) years, 103 students (50 males and 53 females) having class II division 1malocclusion. Lateral and posteroanterior radiographs were taken for each subject. Cranial base measurement included (five angular and seven linear measurements). Mandibular measurement included (six angular and eleven linear measurements). Descriptive statistical analysis was used to describe the data using Pentium computer using SPSS program. Results: Cranial base flexures play a role in determination of lower jaw position which represented by significant effect of cranial base angles (N–S–Ba, N–S–Ar and S–Ba–N) on the angles (SNB, SN–Pog and SN–Id). The increase in the anterior and posterior cranial base lengths (S–N and S–Ba) will affect mandibular dimensions in class II division 1 malocclusion represented by significant effect on (Go–Me, Ar–Go, RW, N–Me , ANS–Me and S–GO). Conclusion: Total cranial base length increase (N–Ba) will have significant effect on all mandibular dimensions in class II division 1 malocclusion (Go–Me, Ar–Go, RW, N–Me, ANS–Me, S–Go, and Co–Gn). Significant effect of both anterior and posterior cranial base widths (GL–GL and Mas–Mas) on mandibular width measured at Condyle, Gonion and Antegonion points. Only (GL–GL) have effect on mandibular width (Lm–Lm).
