Clinical Assessment & Presentations
Intra-oral Features
Obstruction of incisor eruption
Mechanical obstruction with supernumeraries are the most common cause of delayed eruption or ectopic incisors. The above figure is a periapical radiograph of a supernumerary tooth obstructing the upper right permanent central incisor from its normal eruption path.
Other causes of obstruction can be a retained deciduous incisor or local pathology around the incisor.
Abnormal root development
Ectopic or delayed eruption incisors may have abnormal root morphology such as dilaceration. The above figure is a sagittal slice of a CBCT image showing an almost 90 degree dilaceration of the central incisor root. Bringing this tooth into the arch form can be a challenge as the root apex may penetrate the buccal cortex. Treatment of severely dilacerated teeth may involve extraction of the tooth or orthodontic alignment with root canal treatment and an apicectomy.
Pathology associated with incisors
Cysts such as dentriguous cysts can cause ectopic incisors and delayed eruption. Other types of pathologies can be clefting or those of soft tissue in origin such as gingival fibromatosis. Local pathologies need to be carefully investigated for exclusion of systemic causes and more sinister neoplastic causes. (Mittal et al. 2017). Read more at in treatment indications.