Acid challenge exacerbates activation of matrix metalloproteinases in permanent teeth undergoing radiotherapy

Author(s)

de Queiroz, Alexandra Mussolino ; Bonilla, Claudia Maria Carpio ; Furtado, Taissa Cassia de Souza ; Palma-Dibb, Regina Guenka ; Oliveira, Harley Francisco de ; Arnez, Maya Fernanda Manfrin ; Carvalho, Fabricio Kitazono de ; Paula-Silva, Francisco Wanderley Garcia

• Document type: Journal article
• Source: BRAZILIAN ORAL RESEARCH; v. 38, p. 9-pg., 2024-01-01.

Abstract

The aim of this study was to investigate the effect of acid challenge on the activation of matrix metalloproteinases (MMPs) in the Dentinoenamel junction of primary and permanent teeth submitted to radiotherapy. For this purpose, a total of 178 dental fragments obtained from molars were used, and randomly divided into 2 groups (primary and permanent teeth) / 4 experimental subgroups (irradiated and non-irradiated, demineralized and non-demineralized). The fragments were exposed to radiation, with a dose fraction of 2 Gy, for 5 consecutive days, until a total dose of 60 Gy was reached, with a total of 30 cycles, for 6 weeks. To determine the activity of MMPs on the dentinoenamel junction (DEJ), in situ zymography assays on 0.6mm dental fragments were performed. To assess whether MMP activity would be impacted by an acidic environment, the fragments were placed in a demineralizing solution (pH of 4.8). The finding was that irradiation activated MMPs in DEJ and these effects were more evident in permanent when compared with primary teeth. When the effect of an acid challenge on MMPs activity was investigated, demineralization was observed not to increase MMPs activity in non-irradiated teeth, but it did increase MMPs activity in irradiated teeth. In conclusion, an acid challenge was found to exacerbate activation of MMPs in DEJ of permanent teeth submitted to irradiation, but not in primary teeth. (AU)

• FAPESP's process: 21/08558-7 - Study of the effect of gel formulations containing Sr2+ on dentin and bone mineralization in vivo
• Grantee: Taíssa Cássia de Souza Furtado
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/17611-4 - Mechanisms involved in the regulation of 5-lipoxygenase pathway in experimentally-induced apical periodontitis
• Grantee: Francisco Wanderley Garcia de Paula e Silva
• Support Opportunities: Research Grants - Young Investigators Grants