Avaliação da radiopacidade, do pH e da atividade antimicrobiana do MTA, do cimento Portland puro e do cimento Portland adicionado de agentes radiopacificadores

• Autor(a) principal: Lima, Marta Judite Nunes
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFS
• Texto Completo: https://ri.ufs.br/handle/riufs/5904
• topic: Odontologia; Materiais biomédicos; Testes de sensibilidade bacteriana; Materiais dentários; Dentes - radiografia; Radiografia digital; Materiais biocompatíveis; PH; Testes de sensibilidade microbiana; Microbial susceptibility testing; Digital radiography; Biocompatible materials; CIENCIAS DA SAUDE::ODONTOLOGIA

Introduction: The radiopacity is a required property in all dental materials. This characteristic allows this materials be able to be distinguished from the tooth surfaces through the radiography. Portland cement (PC) presents physico-chemical and biological properties similar to mineral trioxide aggregate (MTA), except for radiopacifier. Objective: To evaluate the radiopacity, antimicrobial activity and pH of the MTA, pure PC and PC added different radiopacifiers. Materials and Methods: The radiopacity of MTA, pure PC and PC added the radiopacifying: iodoform, lead oxide, zirconium oxide, bismuth subnitrate, barium sulfate and bismuth oxide in the proportions 15%, 20% and 30% were analyzed. The radiopacity was carried out using a semi-direct digital radiography system (Instrumentarium Kavo EXPRESS®). The PC and cements selected with adequate radiopacity (ANSI/ADA No. 57) were evaluated for their antimicrobial activity and pH. Antimicrobial activity was analyzed by microdilution tests and agar diffusion. The microorganism tested were Enterococcus faecalis, as a standard strain (ATCC 29212) and six clinical strains (LMA 26, LMA 27, LMA 28, LMA 29, LMA 31 and LMA 34). The pH was measured using a digital pH meter (pH Meter Pocket-sized). Statistical analyzes were performed using the Shapiro-Wilk normality test, ANOVA and Tukey with significance level of 5%. Results: Pure PC had the lowest radiopacity. The MTA, PC + iodoform 20% (3.59 mmEq.Al), PC + bismuth oxide 20% (4.79 mmEq.Al), PC + bismuth subnitrate 20% (3.12 mmEq.Al), PC + 20% lead oxide (3.18 mmEq.Al) and PC + 30% zirconium oxide (4.28 mmEq.Al). Regarding the agar diffusion test, the LMA 26 strain was inhibited by PC, PC + Iodoform 20%, PC + 30% Zirconium Oxide, PC + Bismuth subnitrate 20%, and PC + Bismuth Oxide 20%. The LMA 31 strain was inhibited by PC + zirconium oxide 30% and PC + bismuth subnitrate 20% and LMA 27 strain was inhibited by PC + bismuth subnitrate 20%. The other strains were not inhibited. In the microdilution test, most strains was inhibited by tested materials, except the ATCC 29212 strain which was not inhibited by PC + lead oxide 20%. LMA 28 29, 31 and 34 strains were not inhibited by PC + lead oxide 20%and PC + zirconium oxide 30%, in which LMA 28 and 29 strains were not inhibited by PC + bismuth oxide20%. All cements tested showed alkalinity in all experimental periods, in which MTA had the lowest pH. Conclusions: MTA and PC added the radiopacifiers subnitrate bismuth and iodoform in concentrations of 20% by weight, provided satisfactory radiopacity, alkaline medium and promoted bactericidal and bacteriostatic activities against strains of E .faecalis tested.