Postradiation Matrix Metalloproteinase-20 Expression and Its Impact on Dental Micromorphology and Radiation-Related Caries.
Caries Res
; 51(3): 216-224, 2017.
Article
em En
| MEDLINE
| ID: mdl-28359051
ABSTRACT
Recent evidence suggests that head-and-neck radiotherapy (HNRT) increases active forms of matrix metalloproteinase-20 (MMP-20) in human tooth crowns, degrading the dentin-enamel junction (DEJ) and leading to enamel delamination, which is a pivotal step in the formation of radiation-related caries (RRC). Additional participation of enzymatic degradation of organic matrix components in caries progression was attributed to MMP-20 in dentin. Therefore, the current study tested the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes to the enamel and dentin. Thirty-six teeth were studied, including 19 post-HNRT specimens and 17 nonirradiated controls. Optical light microscopy was used to investigate the micromorphological components of the DEJ, dentin-pulp complex components, and carious dentin. The samples were divided into 2 subgroups nondemineralized ground sections (n = 20) and demineralized histological sections (n = 16). In addition, immunohistochemical analysis using the immunoperoxidase technique was conducted to semiquantitatively assess MMP-20 expression in the DEJ, dentin-pulp complex components, and carious dentin. No apparent damage to the DEJ microstructure or other dentin-pulp complex components was observed and no statistically significant differences were detected in MMP-20 expression (p > 0.05) between the irradiated and control groups. This study rejected the hypothesis that MMP-20 is overexpressed in the DEJ, dentin-pulp complex components, and carious dentin of post-HNRT patients, leading to detectable micromorphological changes. Hence, direct effects of radiation may not be regarded as an independent factor to explain aggressive clinical patterns of RRC.
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Base de dados:
MEDLINE
Assunto principal:
Colo do Dente
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Cárie Dentária
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Polpa Dentária
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Dentina
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Metaloproteinase 20 da Matriz
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Neoplasias de Cabeça e Pescoço
Tipo de estudo:
Etiology_studies
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Risk_factors_studies
Limite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article