Novel pulp capping material based on sodium trimetaphosphate: synthesis, characterization, and antimicrobial properties

Objectives: To evaluate the mechanical, physicochemical, and antimicrobial properties of four different formulations containing micro- or nanoparticles of sodium trimetaphosphate (mTMP and nTMP, respectively). Methodology: Four experimental groups were used in this investigation: two mTMP groups and two nTMP groups, each containing zirconium oxide (ZrO2), and solution containing either chitosan or titanium oxide (TiO2) nanoparticles (NPs). Setting time, compression resistance, and radiopacity were estimated. The agar diffusion test was used to assess the antimicrobial activity of the formulations against five different microbial strains: Streptococcus mutans, Lactobacillus casei, Actinomyces israelii, Candida albicans, and Enterococcus faecalis. Parametric and nonparametric tests were performed after evaluating homoscedasticity data (p<0.05). Results: From the properties evaluated, nTMP cements required less setting time and showed greater resistance to compression. Cements containing TiO2 showed greater radiopacity for both nTMP and mTMP. All four cement formulations showed antimicrobial activity against S. mutans and L. casei.  Conclusion: Formulations containing nTMP have shorter setting times and higher compressive strength, and those with TiO2 nanoparticles showed antimicrobial activities. Clinical relevance: The cement containing nTMP, ZrO2, and TiO2 could be an alternative material for protecting the pulp complex

Propriedades antimicrobianas, físico-mecânicas e de liberação de fluoreto do cimento de ionômero de vidro associado ao hexametafosfato de sódio microparticulado e nanoparticulado

The aim of this study was to evaluate antimicrobial, physico-mechanical and fluoride release properties of the glass ionomer cement (GIC) associated with HMP microparticle and nanoparticle. Initially, solutions of HMP were obtained at concentrations of 1, 3, 6, 9 and 12 %, and the antibacterial activity was evaluated against Streptococcus mutans, Lactobacillus acidophilus and Actinomyces israelli by agar diffusion test. The same methodology was used to determine the antimicrobial activity of GIC associated with HMP at concentrations of 6, 9 and 12 % microparticle or nanoparticle. The release of F and HMP were determined in demineralization and remineralization solutions. Furthermore, the resistance to diametral tensile and compression, surface hardness and the degree of conversion of monomers were measured. Parametric and non-parametric tests were performed, after checking homocedasticity data (p < 0.05). The solutions of 6, 9 and 12 % of HMP showed better antimicrobial activity against all bacteria tested, and these concentrations incorporated into the CIV. All concentrations of HMP incorporated into the GIC had antimicrobial activity for all bacteria. There was a dose-response relationship between concentration of HMP in the GIC and antimicrobial activity. Regarding the release of F and HMP, higher values occurred on the first day in all groups and the highest levels of release occurred in groups containing 9 and 12 % of HMP nanoparticle. However the incorporation of HMP in the GIC reduced values of physical and mechanical tests when compared to the GIC, showing a dose-response relationship. It was concluded that the incorporation of HMP in GIC improves antimicrobial activity and increase the release of fluoride, but reduces its physical and mechanical properties. The reduction of particulate HMP led to better antimicrobial and fluoride release resultsO objetivo do presente estudo foi avaliar as propriedades antimicrobianas, físico-mecânicas e de liberação de fluoreto do cimento de ionômero de vidro (CIV) associado ao hexametafosfato de sódio (HMP) microparticulado e nanoparticulado. Inicialmente, foram obtidas soluções de HMP nas concentrações 1, 3, 6, 9 e 12 % e a atividade antibacteriana foi avaliada contra Streptococcus mutans, Lactobacillus acidophilus e Actinomyces israelli por meio do teste de difusão em ágar. A mesma metodologia foi empregada para determinar a atividade antimicrobiana do CIV associado ao HMP nas concentrações de 6, 9 e 12 % microparticulado ou nanoparticulado. Foi determinada a liberação de fluoreto (F) e HMP em soluções de desmineralização e remineralização. Além disso, as resistências à tração diametral e compressão, dureza de superfície e grau de conversão de monômeros foram analisados. Testes paramétricos e não paramétricos foram realizados, após a verificação da homocedasticidade dos dados (p < 0,05). As soluções de 6, 9 e 12 % de HMP apresentaram melhor atividade antimicrobiana contra as bactérias testadas, sendo essas concentrações incorporadas ao CIV. Todas as concentrações de HMP associado ao CIV tiveram atividade antimicrobiana para todas as bactérias. Observou-se uma relação dose-resposta entre concentração de HMP no CIV e a atividade antimicrobiana. Com relação à liberação de F e HMP, os maiores valores ocorreram no primeiro dia em todos os grupos e as maiores médias de liberação ocorreram nos grupos contendo 9 e 12 % de HMP nanoparticulado. Entretanto, a incorporação do HMP ao CIV reduziu as propriedades físico-mecânicas quando comparado ao CIV mostrando uma relação dose-resposta. Concluiu-se que a incorporação de HMP no CIV melhora a atividade antimicrobiana e aumenta a liberação de F, porém reduz suas...Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Effects of sodium hexametaphosphate microparticles or nanoparticles on the growth of saliva-derived microcosm biofilms

Objectives: This study evaluated the effects of sodium hexametaphosphate microparticles (HMPmicro) or nanoparticles (HMPnano) on the growth of saliva-derived microcosm biofilms Materials and methods: Saliva-derived biofilms were formed on glass coverslips for 24 h. Thereafter, Streptococcus mutans (C180-2) was incorporated or not into the biofilms. From that time point onwards, solutions containing 0.2% HMPmicro or HMPnano, combined or not with 220 ppm F, were constantly present in the culture medium. In addition, 220 ppm F alone (220F) and McBain medium without any compound were also tested as positive and negative controls (CTL), respectively. After 96 h, the biofilms were plated on anaerobic blood agar or sucrose agar bacitracin for total and S. mutans CFU-counting, respectively. Biofilms’ lactic acid production was analysed spectrophotometrically. Data were submitted to ANOVA or Kruskal-Wallis’ tests, followed by Student-Newman-Keuls’ test (p<0.05; n=12). Results: HMPmicro or HMPnano led to significantly lower lactic acid production, and significant reductions in total CFU-counting in microcosm biofilms, supplemented or not with S. mutans, in comparison to both controls, with significant differences between 220F and CTL. No significant differences were observed among the groups treated with HMPmicro or HMPnano (with or without F). The same trend was seen for S. mutans CFU-counting, in biofilms supplemented with S. mutans. Conclusions: HMP significantly reduced total and S. mutans CFU counts, as well as lactic acid production by saliva-derived microcosm biofilms. Clinical relevance: These findings in saliva-derived microcosm biofilms suggest that HMP stands as a promising alternative for the control of cariogenic biofilms

The Activity of Calcium Glycerophosphate and Fluoride against Cariogenic Biofilms of <i>Streptococcus mutans</i> and <i>Candida albicans</i> Formed In Vitro

This study evaluated the effects of calcium glycerophosphate (CaGP), with or without fluoride (F), on dual-species biofilms of Streptococcus mutans and Candida albicans. The biofilms were treated three times with 0.125, 0.25, and 0.5% CaGP solutions, with or without 500 ppm F (NaF). Additionally, 500 and 1100 ppm F-solutions and artificial saliva served as controls. After the final treatment, the microbial viability and biofilm structure, metabolic activity, total biomass production, and the composition of the extracellular matrix composition were analyzed. Regardless of the presence of F, 0.25 and 0.5% CaGP promoted a higher biomass production and metabolic activity increase than the controls (p p p < 0.05). It can be concluded that CaGP alone affected the number of bacterial cells and, when combined with F, reduced its production of biomass, metabolic activity, and the expression of the extracellular matrix components

Effects of Sodium Hexametaphosphate and Fluoride on the pH and Inorganic Components of <i>Streptococcus mutans</i> and <i>Candida</i> <i>albicans</i> Biofilm after Sucrose Exposure

In order to improve the anticaries effects of fluoridated products, the supplementation of these products has been considered a promising alternative for caries control. This study evaluated the effects of sodium hexametaphosphate (HMP) and/or fluoride (F) on the inorganic components and pH of Streptococcus mutans and Candida albicans dual-species biofilms. The biofilms were treated 72, 78, and 96 h after the beginning of their formation with 0.25, 0.5, or 1% HMP-containing solutions with or without F (500 ppm, as sodium fluoride). F-containing solutions (500 ppm and 1100 ppm) and artificial saliva were used as controls. The biofilms were exposed to a 20% sucrose solution after the third treatment. Along with the biofilm pH, the concentrations of F, calcium, phosphorus (P), and HMP were determined. HMP, combined with F, increased F levels and decreased P levels in the biofilm fluid compared to that of the solution with 500 ppm F. Exposure to sucrose decreased the concentrations of all ions in the biomass, except for HMP; 1% HMP, combined with F, promoted the highest pH. It can be concluded that HMP affected the inorganic composition of the biofilm and exerted a buffering effect on the biofilm pH

Evaluation of Solutions Containing Fluoride, Sodium Trimetaphosphate, Xylitol, and Erythritol, Alone or in Different Associations, on Dual-Species Biofilms

Although the association of polyols/polyphosphates/fluoride has been demonstrated to promote remarkable effects on dental enamel, little is known on their combined effects on biofilms. This study assessed the effects of solutions containing fluoride/sodium trimetaphosphate (TMP)/xylitol/erythritol on dual-species biofilms of Streptococcus mutans and Candida albicans. Biofilms were grown in the continuous presence of these actives alone or in different associations. Quantification of viable plate counts, metabolic activity, biofilm biomass, and extracellular matrix components were evaluated. Overall, fluoride and TMP were the main actives that significantly influenced most of the variables analyzed, with a synergistic effect between them for S. mutans CFUs, biofilm biomass, and protein content of the extracellular matrix (p S. mutans CFUs and biofilm biomass compared with fluoride alone at the same concentration. It can be concluded that fluoride and TMP act synergistically on important biofilm parameters, and their co-administration with xylitol/erythritol significantly impacts S. mutans CFUs and biomass reduction

Antimicrobial Effect of Low-Fluoride Toothpastes Containing Polyphosphate and Polyols: An In Vitro Assessment of Inhibition Zones

This study evaluated the antimicrobial effect of toothpastes containing 200 ppm fluoride (200F), xylitol (X, 16%), erythritol (E, 4%), and sodium trimetaphosphate (TMP, 0.25%), alone or in different associations, against Streptococcus mutans (SM), Lactobacillus casei (LC), Actinomyces israelii (AI), and Candida albicans (CA). Suspensions of the micro-organisms were added to a BHI Agar medium. Five wells were made on each plate to receive toothpaste suspensions at different dilutions. Toothpastes containing no actives (placebo) or 1100 ppm F (1100F) were used as negative and positive controls. Two-way ANOVA and Tukey’s HDS test were used (p p p p < 0.001). The association of polyols and TMP in a low-fluoride toothpaste effectively reduced the growth of cariogenic micro-organisms (SM, CA, and LC), suggesting that this formulation could be an interesting alternative for children due to its low fluoride content

Activity of Sodium Trimetaphosphate Nanoparticles on Cariogenic-Related Biofilms In Vitro

In light of the promising effect of sodium trimetaphosphate nanoparticles (TMPn) on dental enamel, in addition to the scarce evidence of the effects of these nanoparticles on biofilms, this study evaluated the activity of TMPn with/without fluoride (F) on the pH, inorganic composition and extracellular matrix (ECM) components of dual-species biofilms of Streptococcus mutans and Candida albicans. The biofilms were cultivated in artificial saliva in microtiter plates and treated with solutions containing 1% or 3% conventional/microparticulate TMP (TMPm) or TMPn, with or without F. After the last treatment, the protein and carbohydrate content of the ECM was analyzed, and the pH and F, calcium (Ca), phosphorus (P), and TMP concentrations of the biofilms were determined. In another set of experiments, after the last treatment, the biofilms were exposed to a 20% sucrose solution, and their matrix composition, pH, and inorganic component contents were evaluated. 3% TMPn/F significantly reduced ECM carbohydrate and increased biofilm pH (after sucrose exposure) than other treatments. Also, it significantly increased P and F levels before sucrose exposure in comparison to 3% TMPm/F. In conclusion, 3% TMPn/F affected the biofilm ECM and pH, besides influencing inorganic biofilm composition by increasing P and F levels in the biofilm fluid

Buffering Capacity and Effects of Sodium Hexametaphosphate Nanoparticles and Fluoride on the Inorganic Components of Cariogenic-Related Biofilms In Vitro

Despite the remarkable effects of sodium hexametaphosphate nanoparticles (HMPnano) on dental enamel de-/re-mineralization processes, information on the effects of these nanoparticles on biofilms is scarce. This study assessed the effects of HMPnano, with or without fluoride (F), on the inorganic components and pH of Streptococcus mutans and Candida albicans dual-species biofilms. Solutions containing conventional/micro-sized HMP (HMPmicro) or HMPnano were prepared at 0.5% and 1%, with or without 1100 ppm F. A 1100 ppm F solution and pure artificial saliva were tested as positive and negative controls, respectively. The biofilms were treated three times and had their pH analyzed, and the concentrations of F, calcium, phosphorus, and HMP in the biofilm biomass and fluid were determined. In another set of experiments, after the last treatment, the biofilms were exposed to a 20% sucrose solution, and the biofilm pH and inorganic components were evaluated. The 1% HMPnano solution with F led to the highest biofilm pH, even after exposure to sucrose. The 1% HMPnano solution without F led to significantly higher phosphorus concentrations in comparison to all other groups. It can be concluded that 1% HMPnano and F influenced the biofilm pH, besides affecting most of the inorganic components of the dual-species biofilms