The current study aims to measure the variations of the mesiodistal width of permanent teeth in a sample of patients attending Ajman University Dental Hospital. Materials and Method: A Descriptive cross-sectional study of 85 pretreatment study casts of patients (M:33, F:52) aged between 11-38 attending the Orthodontic unit at Ajman University Dental Hospital. The samples were selected randomly for measurements, which were performed using an electronic digital calibre. The width of an individual tooth is measured accurately from the mesial contact point to the distal contact point. The measurement was performed for all the 12 maxillary and mandibular teeth (from 16 to 26 and 36 to 46). The data put up in an excel sheet and sent to the statistician for analysis. Results: Class I and II showed a higher overall ratio and anterior ratio in males with no difference between the gender neither in the anterior or the overall ratio. At the same time, Class III malocclusion had a significant difference in both overall and anterior ratios. The maxillary 1st premolars and 2nd premolars teeth have insignificant mesiodistal differences between genders, while the maxillary canine and the 2nd premolar have a significant difference between right and left quadrants. The mandibular teeth showed no significant difference in mesiodistal width between right and left quadrants. Conclusion: The insignificant difference between the sample and Bolton in the anterior and posterior ratios in Class I & II cases explain the similarity of the racial feature. There is a significant difference in Class III between our sample and the Bolton original work.