Fernanda Paula Yamamoto-Silva

E-cadherin downregulation and Twist overexpression since early stages of oral carcinogenesis.

There is some evidence of Twist participation in oral carcinogenesis; however, little is known about its interaction with E-cadherin in oral squamous cell carcinoma (OSCC) development. This experimental study included an immunohistochemical analysis of Twist and E-cadherin proteins in paraffin-embedded specimens of oral leukoplakia (OL), OSCC, and normal oral mucosa. In addition, it was also performed a Western blot and double-immunofluorescence analysis of Twist and E-cadherin expression in OSCC cell lines. Significant differences in Twist and E-cadherin immunoexpression were observed between normal oral mucosa and OL, with an inverse relation since the earliest stages of oral dysplasia (r = -0,512; P < 0.001). Western blot and double-immunofluorescence analysis showed differences in Twist and E-cadherin expression among human oral keratinocytes and OSCC cell lines suggesting that downregulation of E-cadherin occurs in a dependent manner of Twist in OSCC. Our results showed a possible value of Twist and E-cadherin in the prediction of risk of oral epithelium malignant transformation.

Multifocal red bands of the marginal gingiva.

Multifocal red bands of the marginal gingiva Brunno Santos de Freitas Silva, DDS, MSc, PhD, Simone Sousa Silva Sant’Ana, DDS, MSc, Satiro Watanabe, DDS, MSc, Eneida Franco Vencio, DDS, MSc, PhD, Virgilio Moreira Roriz, DDS, MSc, PhD, and Fernanda Paula Yamamoto-Silva, DDS, PhD University of Anapolis, Anapolis, Goias, Brazil; Federal University of Goias, Goiânia, Goias, Brazil (Oral Surg Oral Med Oral Pathol Oral Radiol 2015;119:3-7)

Stem Cell Marker Expression in Persistent Apical Periodontitis

Introduction: This study evaluated the expression of CD90 (mesenchymal stem cell) and Sox2 (progenitor stem cell) markers in persistent apical periodontitis (PAP) (n = 16) and primary periapical lesions (PPLs) (n = 10). Methods: All samples were classified histologically according to the intensity of inflammatory cell infiltrate in the periapical lesion. Immunohistochemistry was used to detect CD90 and Sox2 in PAP and PPLs. The Spearman correlation coefficient and the Mann‐Whitney U test were used to analyze data at the 5% significance level. Results: CD90 expression was found in mesenchymal cells and vascular endothelial cells of 68.5% of all cases of PAP. There was no correlation between CD90 expression and histopathological diagnosis (P = .053) or inflammatory cell infiltrate intensity (P = .112). CD90 staining was predominantly found in the vascular endothelial cells of 30% (n = 3) of PPLs. CD90 expression was significantly higher in PAP than in PPLs (Mann‐Whitney U test, P < .05). Sox2 expression was found in all cases of PAP. Eventually, all mesenchymal and chronic inflammatory cells exhibited Sox2 expression. There was no correlation between Sox2 expression and histopathological diagnoses (P = .749), inflammatory cell infiltrate intensity (P = .510), or acute or chronic inflammatory cell infiltrate (P = .256). Sox2 expression was found in 100% of PPLs. There was no difference in Sox2 expression between PAP and PPLs (P = .477). Conclusions: Mesenchymal stem cells may contribute to the immunosuppressive environment in PAP. Additionally, distinct stem cell sources may be associated with the chronic nature of PAP as well as with the development of PPLs.

Chondroblastic osteosarcoma mimicking periapical abscess

Abstract Lesions of non-endodontic origin may mimic periapical abscess. Osteosarcoma is a rare malignant lesion. Case report The present report describes a case of chondroblastic osteosarcoma in the periapical region of teeth #29, #30, and #31 of an 18-year-old male. Clinical history showed self-reported discomfort in the right posterior gingiva for over a month. Physical examination showed a small expansion and redness of the right mandibular buccal and lingual cortical plates, but no signs of pain or inflammation were observed. All the teeth responded positively to pulp sensibility. Periapical and panoramic radiographs showed slight periapical radiolucency in the roots of teeth #29 and #30, clear periodontal ligament space widening, and evident loss of lamina dura. Incisional biopsy was performed, and based on microscopic findings the diagnosis of chondroblastic osteosarcoma was confirmed. Conclusions Non-endodontic diseases associated with tooth root apex, such as chondroblastic osteosarcoma, should be included in differential diagnosis of jaw lesions that resemble periapical abscess.

Influence of voxel size on cone-beam computed tomography-based detection of vertical root fractures in the presence of intracanal metallic posts

Purpose This study was performed to evaluate the influence of voxel size and the accuracy of 2 cone-beam computed tomography (CBCT) systems in the detection of vertical root fracture (VRF) in the presence of intracanal metallic posts. Materials and Methods Thirty uniradicular extracted human teeth were selected and randomly divided into 2 groups (VRF group, n=15; and control group, n=15). The VRFs were induced by an Instron machine, and metallic posts were placed in both groups. The scans were acquired by CBCT with 4 different voxel sizes: 0.1 mm and 0.16 mm (for the Eagle 3D V-Beam system) and 0.125 mm and 0.2 mm (for the i-CAT system) (protocols 1, 2, 3, and 4, respectively). Interobserver and intraobserver agreement was assessed using the Cohen kappa test. Sensitivity and specificity were evaluated and receiver operating characteristic analysis was performed. Results The intraobserver coefficients indicated good (0.71) to very good (0.83) agreement, and the interobserver coefficients indicated moderate (0.57) to very good (0.80) agreement. In respect to the relationship between sensitivity and specificity, a statistically significant difference was found between protocols 1 (positive predictive value: 0.710, negative predictive value: 0.724) and 3 (positive predictive value: 0.727, negative predictive value: 0.632) (P<.05). The least interference due to artifact formation was observed using protocol 2. Conclusion Protocols with a smaller voxel size and field of view seemed to favor the detection of VRF in teeth with intracanal metallic posts.

Systemic corticosteroid in the treatment of a 9-year-old boy with Oral Mucous Membrane Pemphigoid: A case report

Objective: The aim of this report is present a rare case of oral Mucous Membrane Pemphigoid (MMP) in a 9-year-old-boy successfully treated with low doses of systemic corticosteroid. Case description: A 9-year-old boy was referred to our service with the complaint of painful gingiva and generalized burning mouth sensation over 1 year. Intraoral examination revealed desquamative lesions affecting the entire attached gingiva of both the maxilla and the mandible. After the incisional biopsy the MMP diagnosis was confirmed, and the patient was initially treated with dexamethasone 0,1mg/Ml mouth rinse twice daily for 24 weeks. Due the difficulty in eating and the presence of persistent large oral lesions, systemic prednisone 20 mg (1 mg/Kg) was prescribed for 4 weeks with a 5 mg gradual reduction per week over 3 weeks. After initiating the systemic corticosteroid therapy, the patient showed total regression of the lesions, and no indication of recurrence has been observed in the past 6 months. Conclusion: There is no cure for MMP; however, treatment can provide complete and long-lasting remission. Based on this premise, it is plausible to consider not only topical but also low doses of systemic corticosteroids in resistant cases of oral MMP, even in children. These measures could improve the quality of life of these patients by reducing pain and, consequently, improving the child’s eating behavior.

20-year Follow-up of Recurrent Glandular Odontogenic Cyst Mimicking a Periapical Lesion

Abstract Periapical lesions usually are caused by root canal infection; nevertheless, other pathologies may eventually involve the tooth apex, making the correct diagnosis more difficult. Glandular odontogenic cysts (GOCs) are uncommon and, despite their cystic nature, may present an aggressive behavior and a high recurrence rate. This report describes a recurrent GOC mimicking a periapical lesion that was followed up for 20 years. A 45‐year‐old woman described tooth discomfort for several years in the anterior region of the mandible that was not exacerbated during eating or occlusion. Clinical examination revealed no signs of swelling, redness, or inflammation in the gingival or surrounding soft tissue. Nevertheless, periapical radiography showed a well‐defined large radiolucent lesion in the periapical region of teeth #22, #23, #24, and #25. The pulp test confirmed that all these teeth were vital. An incisional biopsy was performed, and with the histopathological diagnosis of an odontogenic cyst, the lesion was enucleated surgically. After recurrence, the extensive periapical multilocular lesions were again surgically removed. Based on the microscopic findings, the final diagnosis was GOC. One year later, there were no signs of recurrence. GOCs associated with the root apex may mimic periapical inflammatory diseases. Clinical, radiographic, and histopathological findings are essential for the diagnosis of inconclusive radiolucent findings in the periapical region. Biopsy specimens should be sent to a specialized oral pathology laboratory.

Altered β-catenin expression in oral mucosal dysplasia: a comparative study

Objective The current study aimed to investigate the β-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa. Material and Methods Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-β-catenin primary antibody. A qualitative β-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher’s exact test were used to verify possible differences in the β-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant. Results Membranous expression of β-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, β-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic β-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001). Conclusions The β-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.