The relationship between tooth size, arch length and arch perimeter in Egyptians

Aim: The present study was conducted to determine the correlation between the combined mesiodistal width of teeth, arch length and arch perimeter in a sample of the Egyptian population.Material and methods: Four hundred and twenty pairs of dental casts were traced using TracerNet. The combined mesiodistal width of teeth (CMWT), arch length (AL) and arch perimeter (AP) were measured. Statistical analysis was conducted utilizing Pearson correlation and paired t-test.Results: The results showed a significant positive correlation in the lower arch between the AP and the AL, the CMWT and AL; p<0.05. There were no significant correlations in the upper arch. There was significant difference between the ratio of the upper and lower AP to CMWT; p=0.00.Conclusions: There were positive correlations between the arch perimeter and arch length, combined mesiodistal width of teeth and the arch length in the lower arch, with no correlation between the arch perimeter and the combined mesiodistal width of teeth. Therefore, during orthodontic diagnosis and treatment planning a thought should be given to treatment options that do not involve reduction of tooth mass. The measured values of the different variables could act as a database describing the tooth width and arch dimensions of the representative sample.