Mesiodistal crowns angulation in class II division 1 malocclusion

الملخص EN

Aims : To evaluate the mesiodistal angulation of the crowns in 50 study models (25 for each sex) of Class II division 1 malocclusion and compare it to 38 study models (19 for each sex) of Class I normal occlusion to find the differences between the two groups so as to provide valuable information in the treatment of Class II division 1 malocclusion.

Materials and Methods : mesiodistal crown angulation is measured as the angle formed between the long axis of the crown and a line perpendicular to the occlusal plane.

The data subjected to statistical analysis at p < 0.05.

Descriptive statistics (mean, standard deviation, minimum, maximum), correlation for all the crowns and comparison between right and left side, male and female and between Class I and Class II were carried out.

Results : significant differences in the angulation of the crowns between the two classes in the buccal segment of the upper dental arches for both sexes with significant higher values in Class II division 1 were found.

For the lower arch there were significant differences in central, lateral incisors and second premolar in males and in all crowns except first molar in females with significant higher values in Class II division 1 indicating that the crowns are more mesially inclined in Class II division 1 malocclusion.

Conclusion : the crowns were more medially inclined for Class II division 1 malocclusion than for Class I occlusion.

There was a correlation among teeth in each quadrant.