Mesiodistal Crown Diameter of Normal Occlusion and Different Malocclusion Groups for a Sample of Kurdish Population of Erbil City

Abstract

It is essential to know the tooth crown size to provide accurate diagnosis and treatment planning to ensure the satisfactory outcome of orthodontic treatment. The aim of the present study was to measure and compare mesiodistal crown diameter of a Kurdish sample in Erbil city with normal and different classes of malocclusion. The mesiodistal tooth width was measured by an electronic digital caliper on a total of 150 (75 males and 75 females) orthodontic models of secondary school students of different occlusal relationships (Class I normal occlusion, Class I, Class II division I, Class II division II, and Class III malocclusions). The results showed that (1) the maxillary right first molar was significantly larger than the left one and both maxillary right lateral incisors and first premolars were larger than their contralateral teeth at the level of P < 0.01. (2) Both upper and lower canine were significantly smaller in females than in males; (3) Class I malocclusion showed tendency toward larger teeth than the rest of the other occlusal categories; (4) no statistically significant differences in tooth size were found among the Class II division I, division II, and Class III malocclusions when compared to normal occlusion. In conclusion, females had smaller teeth than males and there was asymmetry between the right and left sides in tooth size and Class I malocclusion showed tendency toward larger teeth.