Histologic Features of External Cervical Resorption Affecting Impacted Maxillary Canines: A Report of 2 Cases.

Reports on the histopathologic features of external cervical resorption (ECR) in unerupted teeth are scarce. This article reports on 2 maxillary impacted canines from different patients that showed ECR lesions and were surgically removed and histologically evaluated. Case 1 showed symptoms associated with oral communication of the dental follicle and pulpal exposure. Radiographs and cone-beam computed tomographic imaging showed that resorption affected a large part of the root and the crown. Case 2 was asymptomatic, and the resorption cavity was restricted to the tooth crown. Both teeth were extracted and subjected to histologic processing and analysis. In case number 1, the coronal pulp was necrotic and infected, showing areas of exposure to the resorption channels. The apical pulp was vital and uninflamed. The pulp space was surrounded by a continuous pericanalar resorption-resistant sheet. Part of the resorbed area of dentin was occupied by inflamed granulation tissue. More apically, a network of trabecular bone was present in the resorbed area. In case number 2, the pulp around the resorbed area was uninflamed and vital. A large fraction of the lost dentin was replaced by trabecular bone, closely adapted to the irregularly resorbed dentin surface, and no inflammatory cells. Our findings indicate that impacted teeth with ECR may remain asymptomatic until associated with infection. Histologic features of resorption in impacted teeth were similar to those in erupted teeth. In the case associated with infection, the resorbed area was occupied by inflamed tissue and newly formed bone. In the case with no infection, the resorption area was filled with bone undergoing a remodeling process.

An Unusual Case of a Large Periapical Cyst Mimicking a Nasopalatine Duct Cyst.

This article reports on the management of a large median symmetrical lesion of the anterior palate, which was clinically and radiographically diagnosed as an infected nasopalatine duct cyst. However, histopathology demonstrated it to be a radicular cyst of endodontic origin.

Atypically grown large periradicular cyst affecting adjacent teeth and leading to confounding diagnosis of non-endodontic pathology.

This article reports a case of a large osteolytic lesion in the mandible, mostly associated with the apices of the premolars, and suspected as having a non-endodontic origin because the 2 premolars responded positively to the cold sensibility test. The distal border of the lesion reached the mesial root of the first molar, which also had a small lesion in its distal aspect. Cone-beam computed tomography revealed that the large lesion communicated with the small molar lesion. Because the large lesion was suspected as having a non-endodontic origin, surgery was scheduled for enucleation and biopsy. The molar was root canal-retreated, and the 2 premolars treated. Histologic analysis of the premolar pulps showed vitality but advanced degenerative changes. The lesion was histologically diagnosed as an inflammatory periradicular cyst, which originated in the first molar and had an atypical growth to the premolar area. Follow-up revealed that the affected area healed uneventfully.