Mechanical and biological characterization of resin-modified glass-ionomer cement containing doxycycline hyclate

Author(s)

de Castilho, Aline R. F. ^[1] ; Duque, Cristiane ^[2] ; Negrini, Thais de C. ^[3] ; Sacono, Nancy T. ^[4] ; de Paula, Andreia B. ^[5] ; Sacramento, Patricia A. ^[1] ; de Souza Costal, Carlos A. ^[6] ; Spolidorio, Denise M. P. ^[6] ; Puppin-Rontani, Regina M. ^{[1, 5]}

Affiliation

^[1] Univ Campinas UNICAMP, Piracicaba Dent Sch, Dept Pediat Dent, BR-13414903 Sao Paulo - Brazil

^[2] Univ Fed Fluminense, Dept Dent, BR-28625650 Rio De Janeiro - Brazil

^[3] Univ Estadual Paulista UNESP, Araraquara Sch Pharmaceut Sci, Dept Clin Anal, BR-14801902 Sao Paulo - Brazil

^[4] Univ Estadual Paulista UNESP, Araraquara Sch Dent, Dept Orthodont & Pediat Dent, BR-14801903 Sao Paulo - Brazil

^[5] Univ Campinas UNICAMP, Piracicaba Dent Sch, Dept Dent Mat, BR-13414903 Sao Paulo - Brazil

^[6] Univ Estadual Paulista UNESP, Araraquara Sch Dent, Dept Physiol & Pathol, BR-14801903 Sao Paulo - Brazil

• Document type: Journal article
• Source: ARCHIVES OF ORAL BIOLOGY; v. 57, n. 2, p. 131-138, FEB 2012.
• Web of Science Citations: 14

Abstract

Objectives: To characterize the mechanical and biological properties of a resin-modified glass ionomer cement (RMGIC) containing doxycycline'hyclate. Methods: The antibacterial effect of RMGIC containing 1.5, 3.0 and 4.5% doxycycline hyclate was assessed using two experiments - agar diffusion test for 24 h and biofilm assay for 24 h and 7 days - against some cariogenic bacteria. Briefly, base layers of BHI agar and 300 mu L of each inoculum were prepared in Petri dishes with 6 wells that were completely filled with materials. After 24 h incubation, zones of bacterial growth inhibition were measured using a digital caliper. Biofilm assays were conducted using RMGIC specimens immersed in 24-well plates containing the inoculum in BHI broth. After 24 h and 7 days, each specimen were removed, vortexed and the suspension diluted and inoculated in BHI plates for subsequent bacterial counting. Cytotoxicity tests used 50 specimens made in sterilized metal molds, including Vitrebond as positive control. Extracts from every specimen were applied on the MDPC-23 odontoblast-like cells for 24 h. The MIT assay and SEM evaluation determined cell metabolism and morphology, respectively. 80 cylindrical specimens were made from the previously cited groups, and were submitted to testing with a universal testing machine (Instron 4411) using a crosshead speed of 1.0 mm/min for compressive strength and 0.5 mm/mm for diametral tensile strength, respectively. Data from antibacterial and cytotoxic effects, and mechanical properties were submitted to appropriated statistical tests. Results: All tested groups showed growth inhibition of all tested strains (p < 0.05) in 24 h for both microbiological tests, but only 4.5% doxycycline have antibacterial effect after 7 days. None of doxycycline concentrations caused toxic effect to the MDPC-23 cells or presenting alterations to mechanical properties. Conclusion: The incorporation of up to 4.5% doxycycline hyclate into RMGIC inhibits important oral microorganisms, without modifying biological and mechanical characteristics of the dental material, suggesting a new alternative for the treatment of dental caries. (C) 2011 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 08/00359-0 - Evaluation of biological and physico-mechanical properties of glass ionomer cements associated to chlorhexidine or doxycycline as liner material in procedures of partial caries removal
• Grantee: Aline Rogéria Freire de Castilho
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 08/02606-5 - Evaluation of biological and physico-mechanical properties of glass ionomer cements associated to chlorhexidine or doxycycline as liner material in procedures of partial caries removal
• Grantee: Regina Maria Puppin Rontani
• Support type: Regular Research Grants