Tehran University of Medical Sciences, Tehran, Iran ( mirahashemi@tums.ac.ir )

  Background and Aims: Nowadays patients refer to orthodontist for issue such as dental crowding and other aesthetic problems. The aims of this study were to evaluate the relationship between some of mandibular anatomical landmarks and dental crowding in the patient with skeletal Cl II due to mandibular deficiency.

  Materials and Methods: 108 cases have been randomly selected out of patients with mandibular related Cl II problem associated with lower incisor crowding, out of orthodontic patient department of Tehran university of medical sciences. ANB, SNB, mandibular discrepancy, gonial angle, Sn-Go-Gn and IMPA was evaluated out of the data. Lateral cephalograms were used for this matter. The correlation between variables was evaluated by correlation test and after reviewing the data was analyzed using Normality test, the Pearson correlation coefficient was used for normally distributed variables.

  Results: Corpus-ramus length ratio had a significant relationship with dental crowding (P≤0.05) but there was no meaningful and significant relationship between other facial landmarks ( P = 0.26 ).

  Conclusion: there seems to be a slight relationship between facial landmarks and dental crowding in lower incisors. But further case control and clinical studies may be helpful in achieving more reliable data.