Objective: Maxillary impacted or ectopic erupted canines sometimes cause incisal root resorption. It is reported that approximately 10-40% of impacted canines was estimated to occur incisal resorption as determined by radiographic imaging. However, it remains unclear how to predict the incisal pathological resorption associated with impacted canines. In this study, we investigated the clinical factors related to the incisal resorption associated with impacted canines in order to plan the proper treatment.
Methods: Clinical cases associated with maxillary impacted canines were divided into two groups with or without incisal root resorption (resorption group, control). From the basic radiographs, canine inclination to the midline, degree of vertical eruption registered from the canine cusp to the occlusal line and labio-lingual thickness of alveolar bone were measured. Mesio-distal and labio-lingual position of canine cusp, degree of resorption in central and lateral incisors were classified.
Results: In canine inclination to the midline, degree of vertical eruption, mesio-distal position of canine cusp, significant difference was not detected between resorption and control groups. However, labio-lingual position of canine cusp tends to exist central in resorption group than in control group.
Conclusion: This study suggests that the long-term prognosis of maxillary impacted or ectopic erupted canine is important, and appropriate treatment in proper timing is necessary.