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Background & objectives: Ectopic eruption is a disorder in which the tooth does not follow its usual course and if not diagnosed in a timely manner, leads to occlusal problems. The aim of this study was to determine the frequency of ectopic eruption of the first permanent molar and canine in patients referred to Ardabil dental school.
Methods: By observing the panoramic radiographs, recorded from 2016 to 2017, the frequency of ectopic eruption of first permanent molars in children aged 5 to 8 years and permanent canine in children aged 10 to 13 years was determined. The frequency distribution based on sex, involved jaw, unilaterality and bilaterality were evaluated using Chi-Square test.
Results: the frequency of ectopic eruption of the first permanent molar and permanent canine was 2.1% and 6.4% respectively. There was no significant difference in the frequency of ectopic eruption of the first molar, based on the patient's gender (p=0.366), jaw (p=0.132), and unilateral or bilateral involvement (p=0.366).Also, there was no significant difference between the frequency of ectopic eruption of permanent canine and the patient's gender (p=0.384), unilateral or bilateral involvement (p=0.056). The ectopic eruption of the permanent canine in the maxilla was greater than the mandible (p=0.012).
Conclusions: In this study, the frequency values of ectopic eruption were 2.1% and 6.4% for the first permanent molar and permanent canine respectively that were in the range of other studies reported from other populations.