Abstract There are many glass ionomer cements available on the Brazilian market for Atraumatic Restorative Treatment (ART), however, there is still a gap in the literature regarding their cost-effectiveness. Objectives To evaluate the influence of restorative materials (Ketac Molar, 3M ESPE; and Vitro Molar, Nova DFL) in the two-year survival rate and cost-effectiveness of occluso-proximal ART restorations in primary molars. Methodology A total of 117 children (aged four to eight years) with at least one occluso-proximal carious lesion in primary molars were selected and randomly divided in treatment groups (KM or VM) in this parallel randomized controlled trial. Treatments followed ART premises and were conducted in public schools by trained operators in Barueri, Brazil. A trained, calibrated, and blinded examiner performed the evaluations after two, six, 12, and 24 months (k=0.92). Kaplan-Meier survival analysis was used to estimate restoration survival and Cox regression was used to test the association with clinical factors (α=5%). For cost analysis, material and professional costs were considered. Monte Carlo analysis was used to generate a cost-effectiveness plane and bootstrapping was used to compare material costs over the years. Results The overall survival rate was 36.9% after two years (48.6% for KM and 25.4% for VM). Restorations with VM failed more than those with KM (HR=1.70; 95% CI=1.06–2.73; p=0.027). VM presented lower initial cost, but no difference was observed between groups considering the two-year incremental cost. Conclusion After a two-year evaluation, KM proved to be a better option than VM for occluso-proximal ART restorations in primary molars. ClinicalTrials.gov: NCT02267720

Abstract High viscous glass ionomer cement (GIC) has gained popularity as a restorative material; however, high wear is pointed as one of the major drawbacks of this material. Protective surface coatings were developed to protect GIC from water contamination with the additional advantage of occluding any surface cracks or porosities commonly found in this material, possibly resulting in an increased wear resistance of the restorations. Objective: The objective of this study was to investigate the clinical wear of GIC approximal restorations in primary molars protected either with a nanofilled self-adhesive light-cured protective coating (NPC) or with petroleum jelly. Material and Methods: Approximal caries lesions in primary molars from 32 schoolchildren previously enrolled in another clinical trial were included in this investigation. GIC restorations were performed according to the Atraumatic Restorative Treatment approach and protected with either petroleum jelly or a NPC. Impressions of the restored hemiarch were done after 1 day and 6, 12, 24 and 36 months. The impressions were scanned in a 3-D appliance and the obtained images were superimposed using an appropriate computer software. Two-way ANOVA for repeated measures and Tukey's post-hoc test were used to analyze the wear of restorations (α=5%). Results: A significant difference was found between the two groups, with a wear protection offered by the application of a NPC. Conclusion: These results suggest that the application of a NPC has a protective effect on the clinical wear of approximal GIC restorations in primary teeth.

Monitoring traumatic dental injury (TDI) in primary teeth through epidemiological cross-sectional surveys provides descriptive information relevant to the development of public policies focused on the prevention of such injuries for the target population. The aim of this study was to assess the prevalence of TDI in 5- to 6-year-old Brazilian children and its association with biological and socioeconomic factors. A total of 684 children aged 5 to 6 years old, from 11 public schools in the city of Barueri (Brazil) were evaluated. Clinical examinations were carried out in the schools, by two trained and calibrated examiners. Gauze and a mouth mirror were used for the examinations. The reported TDIs were classified according to the Andreasen (2007) criteria for primary teeth. The results showed that 52.3% of the children had TDI. Enamel fracture (63.4%) was the most frequently observed sign of TDI, and the most affected teeth were the primary maxillary central incisors (26.9% maxillary right central incisor and 24% maxillary left central incisor). There was no association between the presence of TDI and biological or socioeconomic factors. In conclusion, the prevalence of TDI was high and had no statistically significant association with biological and socioeconomic factors.

Clinical trials are normally performed with well-known brands of glass ionomer cement (GIC), but the cost of these materials is high for public healthcare in less-affluent communities. Given the need to research cheaper materials, it seems pertinent to investigate the retention rate of a low-cost GIC applied as atraumatic restorative treatment (ART) sealants in two centers in Brazil. Four hundred and thirty-seven 6-to-8-year-old schoolchildren were selected in two cities in Brazil. The children were randomly divided into two groups, according to the tested GIC applied in the first permanent molars. The retention rate was evaluated after 3, 6 and 12 months. Kaplan-Meier survival analysis and the log-rank test were performed. The variables were tested for association with sealant longevity, using logistic regression analyses (α = 5%). The retention rate of sealants after 12 months was 19.1%. The high-cost GIC brand presented a 2-fold-more-likely-to-survive rate than the low-cost brand (p < 0.001). Significant difference was also found between the cities where the treatments were performed, in that Barueri presented a higher sealant survival rate than Recife (p < 0.001). The retention rate of a low-cost GIC sealant brand was markedly lower than that of a well-known GIC sealant brand.

O objetivo deste estudo foi avaliar a microdureza Knoop de três cimentos de ionômero de vidro de alta viscosidade: G1 - Ketac Molar; G2 - Ketac Molar Easymix (3M ESPE) and G3 - Magic Glass ART (Vigodent). Adicionalmente, como um co-objetivo, três diferentes formas de inserção do Ketac Molar Easymix foram avaliadas: G4 - espátula conventional; G5 - seringa comercial (Centrix) e G6 - seringa de baixo custo. Dez corpos de prova de cada grupo foram preparados e a microdureza Knoop foi determinada com 5 indentações por espécime com o aparelho HM-124 (25 g/30 s tempo de identação) após 24 h, 1 e 2 semanas. Durante todo o período de teste, os espécimes foram mantidos em parafina líquida a 37ºC. Diferenças estatísticas significantes foram encontradas entre G3 e G1 / G2 (ANOVA a 2 critérios e teste de Tukey post hoc; p<0,01). Não houve diferença nos resultados no que se refere às diferentes formas de inserção. O cimento de ionômero de vidro Magic Glass ART apresenta os valores mais baixos de dureza enquanto o método de inserção não influencia nos resultados de dureza.

The aim of this study was to assess the Knoop hardness of three high viscous glass ionomer cements: G1 - Ketac Molar; G2 - Ketac Molar Easymix (3M ESPE) and G3 - Magic Glass ART (Vigodent). As a parallel goal, three different methods for insertion of Ketac Molar Easymix were tested: G4 - conventional spatula; G5 - commercial syringe (Centrix) and G6 - low-cost syringe. Ten specimens of each group were prepared and the Knoop hardness was determined 5 times on each specimen with a HM-124 hardness machine (25 g/30 s dwell time) after 24 h, 1 and 2 weeks. During the entire test period, the specimens were stored in liquid paraffin at 37ºC. Significant differences were found between G3 and G1/G2 (two-way ANOVA and Tukey's post hoc test; p<0.01). There was no significant difference in the results among the multiple ways of insertion. The glass ionomer cement Magic Glass ART showed the lowest hardness, while the insertion technique had no significant influence on hardness.

The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11) were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05). The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.