Abstract
Background: Permanent tooth impaction is a relatively common abnormality in which early treatment
can prevent from other developmental disorders. Maxillary central impaction can occur because of
mesiodens, dilacerations, trauma to deciduous tooth and space deficiency. Prevalence of maxillary
central impaction is 0.06%-2.0%.
Methods: In this retrospective, case-control study, 28 people with impacted maxillary central incisor
and 56 as the control group were studied. All participants were 8-12 years old. The data were collected
from private offices of orthodontists and special pediatric dentists and Hamadan dental school. The
data required were diagnostic models, initial panoramic radiography and initial lateral cephalometry
radiography. Data analysis was done by SPSS software using t test and chi-square test. 3\
Results: The most common causes of maxillary central impaction were: mesiodens (74.4%), dilacerations
(14.3%), space deficiency (10.7%) and cyst (3.6%). 89.3% of cases had unilateral maxillary central
impaction and 10.7% had bilateral maxillary central impaction. There was a significant relation between
skeletal class II and maxillary central impaction. ANB angle was significantly higher in impaction group
than in control group (P<0.05). In most of the patients with maxillary central impaction, ipsilateral
canines had upper position compared with the contralateral side (60%).
Conclusions: Presence of mesiodens was the most important reason for maxillary central incisor
impaction, and class II jaw relation is more common in patients with maxillary central incisor
impaction, which higher incidence of vertical disorders can be a bigger challenge in these patients.