Abstract This in vitro study evaluated the impact of TiO2 nanotubes (n-TiO2) incorporated into glass ionomer cement (GIC) on Streptococcus mutans (S. mutans) characteristics at cellular and molecular levels. n-TiO2, synthesized by the alkaline method (20 nm in size), was added to Ketac Molar EasyMix® at 0%, 3%, 5%, and 7% by weight. S. mutans strains were cultured on GIC disks with addition or not of n-TiO2 for 1, 3, and 7 days and the following parameters were assessed: inhibition halo (mm) (n=3/group); cell viability (live/dead) (n=5/group); cell morphology (SEM) (n=3/group); and gene expression by real-time PCR (vicR, covR, gtfB, gtfC, and gtfD) (n=6/group). The data were analyzed by the Kruskal-Wallis test, repeated-measures ANOVA or two-way ANOVA, and Tukey’s and Dunn’s post-hoc tests (α=0.05). The agar diffusion test showed a higher antibacterial property for 5% n-TiO2 compared with 3% and 7% (p<0.05) with no effect of time (1, 3, and 7 days). The cell number was significantly affected by all n-TiO2 groups, while viability was mostly affected by 3% and 5% n-TiO2, which also affected cell morphology and organization. Real-time PCR demonstrated that n-TiO2 reduced the expression of covR when compared with GIC with no n-TiO2 (p<0.05), with no effect of time, except for 3% n-TiO2 on vicR expression. Within-group and between-group analyses revealed n-TiO2 did not affect mRNA levels of gtfB, gtfC, and gtfD (p>0.05). Incorporation of n-TiO2 at 3% and 5% potentially affected S. mutans viability and the expression of key genes for bacterial survival and growth, improving the anticariogenic properties of GIC.

RESUMO O objetivo do presente estudo é apresentar uma abordagem de tratamento em um caso de cárie na primeira infância (CPI). Uma menina de 5 anos foi encaminhada à área de Odontopediatria com múltiplas perdas dentárias precoces, dificuldades mastigatórias, amamentação prolongada e baixa qualidade de vida, com diagnóstico de CPI severa. Um plano de tratamento em três fases foi implementado: 1. Controle da doença – consistindo em mudanças comportamentais nos hábitos de higiene bucal, orientação alimentar, remoção profissional do biofilme seguida de aplicação de flúor e restaurações provisórias; 2. Controle de infecção – exodontias e pulpotomia; e 3. Reabilitação funcional – restaurações diretas e semi-indiretas de resina, próteses parcial e total removíveis nos maxilares inferior e superior, respectivamente. Em conclusão, a abordagem multidisciplinar proposta resultou em um impacto positivo na nutrição e crescimento do paciente, produção da fala, comunicação, autoimagem e socialização, levando a uma melhoria da qualidade de vida.

ABSTRACT The aim of the current study is to present a treatment approach in a case of severe early childhood caries (ECC). A 5-year-old girl was referred to the Pediatric Dentistry Division with multiple premature tooth loss, masticatory difficulties, prolonged breast-feeding, and low quality of life, who was diagnosed with severe ECC. A three-phased treatment plan was implemented: 1. Disease control – consisting of behavioral changes in oral hygiene habits, diet guidance, professional biofilm removal followed by fluoride application and temporary restorations; 2. Infection control – teeth extractions and pulpotomy; and 3. Functional rehabilitation – direct and semi-indirect resin restorations, a removable partial and total prostheses in the lower and upper jaws, respectively. In conclusion, the proposed multidisciplinary approach resulted in a positive impact on the patient’s nutrition and growth, speech production, communication, self-image, and social functioning leading to an improved quality of life.