Comparison Of Arch And Alveolar Width Between Different Sagittal Skeletal Morphology In Teenage

Objective: The aim of this study was to compare the transverse dimensions of the dental arches and alveolar widths between different sagittal skeletal morphology in average facial pattern teenage patients.Methods: Dental casts of one hundred and twenty untreated patients aged between 13-15 years were collected in this study. They were equally divided between males and females,consisting of 40 skeletal class Ⅰ,skeletal classⅡ and skeletal class Ⅲmalocclusion. All patients were selected from October 2012 to February 2015 in Dalian Stomatological Hospital. The average pre-treatment age was 13.67±0.78 years. Twelve liner measurements were utilized for each dental arch. The results were analyzed by SPSS17.0 software package by means of t-test and least significant difference(LSD) test.Results: The findings of this study indicated that all measured dimensions were significantly greater in males than females. Statistical comparisons of the three groups showed no significant differences in maxillary and mandibular intercanine width, differences were found in intercanine and intermolar widths. The skeletal class Ⅲsubjects had the greatest lower premolar and molar width, but showed no significant difference in upper dental measures when compared with class Ⅰ subjects, the upper premolar and molar width measures were significant narrower in skeletal class Ⅱwhen compared with classⅡ and class Ⅲ samples. The lower premolar and molar width measures were significant narrower in skeletal class Ⅱ when compared with class Ⅲ samples, and showed no difference with class Ⅰ samples. Samples in class Ⅰ group had the greatest upper arches in all three alveolar measures. Comparisons in lower alveolar arches showed no significant differences in the three groups except forthe molar dimension.Conclusion: No significant differences exist in maxillary and mandibular intercanine width. Therefore, canine arch width should not be rashly expanded. Rapid maxillary expansion should be considered for both class Ⅱ and class Ⅲ patients in there early treatment time.