The aim of the present study was to evaluate the influence of sodium trimetaphosphate (TMP), associated or not with fluoride (F), on the concentrations of F, calcium (Ca), and phosphorus (P) and on the pH of mixed biofilms of Streptococcus mutans and Candida albicans, before and after exposure to sucrose. The biofilms received three treatments (72, 78, and 96 h after the beginning of their formation), at three TMP concentrations (0.25, 0.5, or 1%), with or without F at 500 ppm. Solutions containing 500 and 1,100 ppm F as well as artificial saliva were also tested as controls. Biofilm pH was measured and the concentrations of F, Ca, and P were determined (solid and fluid phases). In a parallel experiment, after the third treatment (96 h), the biofilms were exposed to a 20% sucrose solution to simulate a cariogenic challenge and the pH of the medium, F, Ca, P, and TMP were determined. The data were submitted by two-way ANOVA, followed by Fisher’s least significant difference test (p < 0.05). Treatment with TMP and 500 ppm F led to higher F concentration in the biofilm fluid. Although TMP did not affect Ca concentrations, biofilms treated with TMP alone presented higher P concentrations. Treatment with 1% TMP and F led to the highest pH values of the biofilm, both before and after the cariogenic challenge. It was concluded that TMP increases F and P in the biofilm and that its presence promotes an increase in the pH of the medium, even after the cariogenic challenge.

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.

Luxação intrusiva é o deslocamento do dente em seu alvéolo, na direção axial, favorecido pela baixa resiliência do osso alveolar. Clinicamente, esse trauma pode apresentar: Grau I (intrusão parcial leve, em que mais de 50% da coroa é visível), Grau II (intrusão parcial moderada, em que menos de 50% da coroa é visível), Grau III (intrusão severa ou completa da coroa). O objetivo desse estudo foi relatar um caso de luxação intrusiva Grau III em uma criança, discutido aspectos acerca de seu diagnóstico, modalidade terapêutica e o acompanhamento do caso. Um paciente de 15 meses de idade, compareceu à Bebê Clínica da Faculdade de Odontologia de Araçatuba uma semana após sofrer um trauma.  O exame clínico revelou gengivas inchadas além da ausência do elemento 51. Após exame radiográfico, a intrusão completa do dente 51 foi confirmada, com o deslocamento do ápice da raiz para a direção vestibular. O tratamento foi aguardar a reerupção espontânea do dente; além de orientações quanto ao alívio oclusal (controle do uso de bicos, e hábitos bucais como onicofagia) e sobre higiene bucal. Após três meses de acompanhamento, a erupção total do dente 51 foi observada, e a gengiva assim como o ápice do dente traumatizado apresentavam aspecto normais. Pode-se concluir que controle clínico e radiográfico, especialmente em casos de injúrias traumáticas em dentes decíduos, além de monitorar o caso até a erupção do dente permanente, detectando possíveis sequelas no dente sucessor e podem se apresentar como alternativas eficientes para o tratamento da luxação intrusiva em dentes com rizogênese incompleta.