## 4 Discussion
This could be due to the influence of study sample selections and ethnic variations. Regarding anterior cranial base length, no significant differences were found between the skeletal groups. In agreement with our results, previous data demonstrated no significant difference in anterior cranial base length between the skeletal groups [1; 31; 32]. On the other hand, other studies reported increased anterior cranial base length in class II malocclusions [6; 7; 33], while in class III malocclusions, a shorter anterior cranial base was observed [15; 34]. The different results could be due to different ethnic groups and the method of data analysis. In terms of posterior cranial base length, it is worth noting that there is debate about whether to use the Basin or articular landmarks [6]. [PERSON] suggested the use of the articular point as a landmark for posterior cranial base measurements since it is easier to locate [35]. Other investigators recommended Basin landmarks for measuring the cranial base [5]. However, it was reported that using the Basin or articular points was very similar [36]. In the present study, Basin landmarks were used in measuring the posterior cranial base length and cranial base angle. Our study findings showed that the posterior cranial base length was statistically significantly different among the skeletal groups. Skeletal class II subjects have smaller posterior cranial base lengths compared to skeletal classes I and III. These findings are consistent with the [PERSON] et al. study [37]. However, it is important to mention that controversial data were found regarding the relationship between posterior cranial base lengths and skeletal malocclusion. For example, a study found that increased posterior cranial base length was associated with class II subjects compared to class I subjects [2]. Moreover, a reduced posterior cranial base length was noted in class III malocclusions [15]. In addition, other studies reported no differences in posterior cranial base length in the skeletal groups [1; 6; 31; 32]. The controversial results could be due to different study samples and ethnic variations. Moreover, it is important to point out that there were more female subjects in the class II group (61.11%) in our study sample, and this might lead to the smaller cranial measurements in the class II group compared to the other groups. Significant differences were found in the total cranial base length between the three skeletal patterns. Skeletal class II had a significantly smaller total cranial base length compared to the other skeletal patterns. In contrast to our results, [PERSON] et al. demonstrated that total cranial base length was significantly larger in class II subjects than in class III [7]. The discrepancy between these results and those presented in previous studies can be attributed to sampling selection and different radiographic tools. Our theory is that reduced posterior and total cranial base length in class II subjects could be due to genetic influence [38]. Negative influence on _Runt-Related Transcription Factor 2 (RUNX2)_ leads to mandibular retrognathism and skeletal class II malocclusion [38; 39]. In addition, inhibition of _RUNX2_ induces early ossification of the spheno-occipital synchondrosis [40]. Regarding cranial base angle, our findings revealed no significant difference in the cranial base angle in all skeletal groups. These results coincide with the findings of previous data [1; 22; 41]. However, other studies reported a significant difference in the cranial base angle in different skeletal patterns [6; 32; 42; 43]. Meanwhile, our results demonstrated that the cranial width and transverse jaw dimensions showed no significant differences among the skeletal groups. To date, no previous studies have investigated the relationship between the cranial base and maxillomandibular transverse relationship. The present analysis demonstrated the gender differences in cephalometric values.