The evaluation of relationship between skeletal classification in sagittal direction and dental arch widths in untreated individuals

The aim of our study is to assess the relationship between the sagittal position of the jaws and the dental arch widths in untreated individuals. In our study, a total of records of 158 patients with a mean age of 18.34 ± 2.21 years, 55 (34.8%) male and 103 (65.2%) female, were used. Three main groups were formed as Angle Class I,II and III malocclusions. Intercanine, interpremolar, intermolar and arch depths were calculated. SNA, SNB, ANB angles and Wits values were measured from lateral cephalometric radiographs. For statistical analysis, Shapiro Wilks, Oneway Anova Tukey HDS test and Pearson correlation analysis were used. It was found that the average upper intercanine width in Class I malocclusion was statistically significantly higher than Class II malocclusion group. In the Class II group, average width between the upper intermolar width was found to be statistically significantly lower than the average of Class III malocclusion group and there was no statistically significant difference between the other classes. There was no positive or negative correlation between the cephalometric values and arch measurements in the Class I malocclusion group. The highest correlation in the Class II group was found between the SNA angle and upper intercanine width, while in the Class III malocclusion group, the highest correlation was found between the SNB angle and upper intercanine width. The most significant difference between malocclusion classes is generally seen in the arch widths of the upper jaw. When the findings of our study were interpreted, we found that the arch widths were affected by the position of the jaws in sagittal direction and their relation to each other.