Fernando José de Oliveira Nóbrega

A Rare Case of Intraoral Nodular Fasciitis: Diagnosis and Immunohistochemical Profile

Nodular fasciitis is a benign, idiopathic, reactive proliferation of myofibroblasts found in the subcutaneous fascia; intraoral occurrence is very rare. An 18-year-old woman was referred to the oral diagnosis service with a 1-month history of a nodular mass in the gingiva. Clinical examination disclosed a well-circumscribed, mobile, pedunculated mass in the left mandibular gingiva. The clinical diagnoses included pyogenic granuloma. She underwent an excisional biopsy under local anesthesia through an intraoral approach. Microscopic examination showed a proliferation of spindle cells arranged in intersecting fascicles. The spindle cells exhibited plump, vesicular nuclei without significant pleomorphism. Scattered multinucleated giant cells also were present. Immunohistochemical stains showed that the lesional cells were positive for smooth muscle actin and vimentin and negative for S-100 protein. The features were those of an inflammatory, benign myofibroblastic lesion, consistent with intraoral nodular fasciitis.

Study of the participation of MMP-7, EMMPRIN and cyclophilin A in the pathogenesis of periodontal disease.

BACKGROUND AND OBJECTIVE Periodontal disease is an infectious disease resulting from the immunoinflammatory response of the host to microorganisms present in the dental biofilm which causes tissue destruction. The objective of this study was to evaluate the immunohistochemical expression of matrix metalloproteinase 7 (MMP-7), extracellular matrix metalloproteinase inducer (EMMPRIN) and cyclophilin A (CypA) in periodontal disease. DESIGN Gingival tissue samples were divided as follows: clinically healthy gingiva (n=32), biofilm-induced gingivitis (n=28), and chronic periodontitis (n=30). Histological sections of 3μm were submitted to immunoperoxidase method and undergone quantitative analysis. The results were analyzed statistically by the Mann-Whitney and Spearman correlation tests, with the level of significance set at 0.05 (α=0.05). RESULTS Immunopositivity for MMP-7, EMMPRIN and CypA differed significantly between the three groups, with higher percentages of staining in chronic periodontitis specimens, followed by chronic gingivitis and healthy gingiva specimens (p<0.05). Immunoexpression of CypA and MMP-7 was higher in the intense inflammatory infiltrate observed mainly in cases of periodontitis (p<0.05). CypA expression was positively correlated with MMP-7 (r=0.831; p<0.001) and EMMPRIN (r=0.289; p=0.006). In addition, there was a significant positive correlation between probing depth and expression of MMP-7 (r=0.726; p<0.001), EMMPRIN (r=0.345; p=0.001), and CypA (r=0.803; p<0.001). CONCLUSION These results suggest that MMP-7, EMMPRIN and CypA are associated with the pathogenesis and progression of periodontal disease.

Clinical Efficacy of Fluoride Varnish and Low-Level Laser Radiation in Treating Dentin Hypersensitivity

The objective of this study was to compare the efficacy of fluoride varnish (Fluorniz(r)) and irradiation with a gallium-arsenide-aluminum diode laser in the treatment of cervical dentin hypersensitivity. Cervical dentin hypersensitivity (CDH) is a painful condition that is highly prevalent in the worlds adult population, with one in six patients presenting this symptom. Eighty-six teeth were divided into two groups: Group 1, teeth treated with Fluorniz; Group 2, teeth irradiated with a GaAlAs laser at a 4 J/cm2 dose. The two treatments were applied to the buccal cervical region in four sessions, at intervals of 72 to 96 h. The response of the patient to tactile and thermal-evaporative stimuli was rated on a visual analog scale. The results showed a reduction of hypersensitivity in response to tactile and thermal-evaporative stimulation at the end of treatment in both groups. In conclusion, short-term treatment with Fluorniz was found to be more effective than low-level laser radiation in reducing cervical dentin hypersensitivity.

Myofibroblasts and mast cells: influences on biological behavior of odontogenic lesions

Odontogenic lesions differ in their rate of recurrence and aggressiveness. This study aimed to evaluate the presence of myofibroblasts and mast cells in odontogenic lesions. Sample consisted of 20 cases each of dentigerous cysts, odontogenic keratocysts, and solid ameloblastomas. Histologic sections were submitted to immunohistochemistry using anti-α-smooth muscle actin and anti-tryptase antibodies. Myofibroblasts and mast cells were counted at ×400 magnification in 5 and 10 fields, respectively. Myofibroblasts were more frequent in ameloblastomas (24.41), followed by odontogenic keratocysts (16.21) and dentigerous cysts (11.85; P=.002). Granulated and degranulated mast cells were more frequent in dentigerous cysts (7.88 and 8.96, respectively), followed by odontogenic keratocysts (6.53 and 7.08) and ameloblastomas (5.21 and 1.88). The difference was only significant for degranulated mast cells (P<.05). Analysis of the correlation between myofibroblasts and mast cells (granulated and degranulated) revealed a moderate positive correlation only in ameloblastomas (R=0.621, P=.003). Probably, myofibroblasts are related to the biological behavior of the odontogenic lesions studied, particularly their aggressiveness. On the other hand, mast cells seem to be associated with inflammatory processes, which are more frequent in cystic lesions than in benign neoplasms. In addition, mast cells may induce the differentiation of fibroblasts into myofibroblasts, thus increasing the number of the latter.

Significance of metalloproteinases in the progression of the periodontal disease

Objectives: The objective of this study was to evaluate the immunohistochemical expression of matrix metalloproteinases (MMPs) -1, -2 and -9 in the progression of the periodontal disease. Materials and methods: Thirteen gingival biopsies with clinical diagnosis of gingivitis and 13 with periodontitis were obtained and processed by immunohistochemical method. Staining of MMPs was scored according to intensity, both in epithelium and in connective tissue, in absent staining (-) which was attributed the score 0; weak staining (+), score 1; and strong staining (++), score 2. Results: MMP-1 has expressed significantly more than the others MMPs in gingivitis both in the epithelium (p=0.0008) and connective tissue (p=0.0049). In periodontitis, both MMP-1 and MMP-9 has expressed significantly in the epithelium (p<0,0001) and in the connective tissue (p=0.0002). MMP-1 and MMP-9 presented more expression in periodontitis than in gingivitis but, MMP-1 only in connective tissue (p=0,03) and MMP-9 in the epithelium (p=0.003) and in the connective tissue (p=0.04). Conclusion: These results indicate MMP-1 have an important role in connective tissue degradation and bone loss and MMP-9, that has expressed more in periodontitis, may have some role in the progression of gingivitis to periodontitis by acting in bone resorption.