Immunohistochemical localization of endothelin-1 in placenta and fetal membranes in term and preterm human pregnancy

A case is reported in which an intruded incisor was initially treated by an endodontic dressing with calcium hydroxide and then extruded using a removable orthodontic appliance. A follow-up examination seven years after completion of endodontic therapy and bleaching showed a favourable response. A review of the relevant literature indicates that intrusion occurs in five to twelve per cent of luxation cases. In this type of injury maximum damage occurs to the pulp and all supporting structures because the tooth is driven into the alveolar process. Complications which have been reported include: pulp necrosis, apical radiolucencies, partial or total pulp calcification, root resorption (surface, inflammatory or replacement), marginal periodontal bone breakdown, and arrested or disturbed root development. The prognosis for pulp survival after intrusion is much more favourable for teeth with incomplete root formation than for teeth with complete root formation. Treatment options available to bring an intruded tooth into alignment are: to await spontaneous re-eruption which may occur if root formation is incomplete, uncovering of the intruded crown, orthodontic extrusion which is allied with gentle luxation if the tooth does not move, and immediate surgical repositioning.