Considering the severity and high prevalence of ECC, as well as the importance of early intervention and approach, the Atraumatic Restorative Treatment program, because of its advantages, consists of an important treatment alternative. However, only a few studies assess ART in babies affected by ECC. For this practice to be accepted as safe, scientific evidence must be built through longitudinal studies to evaluate ART performance and to this end, the present study is justified. Therefore, the aim of this research was to evaluate the effectiveness of Atraumatic Restorative Treatment performed in babies suffering from ECC after a 4-year period and compare the clinical performance of Atraumatic Restorations performed with two different glass ionomer cements. The investigator's hypothesis is that there is no difference in the clinical performance of ARTs performed with the different GICs.

The study is characterized by longitudinal follow-up of a randomized, double-blind, split-mouth-type clinical trial performed in babies affected by early childhood caries. The subjects were children of both sexes, aged between 18 and 36 months, with at least one deciduous molar in each of the different dental quadrants, presenting active cavitated lesions of shallow or medium depth, involving only the occlusal surface. The initial convenience sample consisted of 100 deciduous molars of 25 children attending Bebê Clínica of the School of Dentistry of the Federal University of Rio Grande do Sul-FO / UFRGS, Porto Alegre-RS, Brazil;

The study is characterized by longitudinal follow-up of a randomized, double-blind, split-mouth-type clinical trial performed in babies affected by early childhood caries. The subjects were children of both sexes, aged between 18 and 36 months, with at least one deciduous molar in each of the different dental quadrants, presenting active cavitated lesions of shallow or medium depth, involving only the occlusal surface. The initial convenience sample consisted of 100 deciduous molars of 25 children attending Bebê Clínica of the School of Dentistry of the Federal University of Rio Grande do Sul-FO / UFRGS, Porto Alegre-RS, Brazil; this number being based on similar studies published in the literature [27, 28, 29]. The power of the sample was calculated using the PEPI program, version 4 (Computer Programs for Epidemiologists), for a significance level of 5%. Considering that the average success percentage in two years of ART on primary teeth facings was 88%, and the worst result found was 67% [30], the power obtained was of 70.1%.

All children in the study were enrolled in the oral health promotion program for babies, in which mothers accompanied by their children individually received information and guidance on food intake, breastfeeding, and oral hygiene. In addition to the guidance that was reinforced at each visit, children received topical application of fluoride by brushing with acidulated phosphate fluoride gel in four applications with intervals of one week, considering that all had active cavities [31].

The clinical trial was performed through the experimental split-mouth model, in which the 25 selected children had their teeth distributed randomly through a random number table, receiving ART restorations of a face with one of the two high-viscosity conventional glass ionomer cements studied: Vitro Molar® (DFL, Rio de Janeiro, Brazil) and Ketac Molar Easy Mix® (3M ESPE, St Paul, MN, USA). The atraumatic restorations were performed in the dental office by a single operator trained in the ART Technique [20], who received the restorative material already prepared by a trained auxiliary, ensuring blinding of the study. The restorative procedure performed in relative isolation and without the use of anesthesia consisted of removal of the carious tissue using hand instrument excavators and dentin spoons, with subsequent conditioning of the cavity with a polyacrylic acid solution at 11.5% (DFL) applied with a microbrush for 10 seconds. Immediately after, the cavity was washed and dried with cotton balls. In this step, according to the randomization, the respective GIC was inserted and subsequent digital compression was performed for 30 seconds. After occlusal adjustment, the ARTs were protected with finish gloss Alfa Bond® (DFL).

Clinical assessments were carried out in three stages: after 1, 2 and 4 years. For this, the oral health status of the children was assessed by the presence of visible plaque and caries activity, and the quality of ART restorations by the ART criterion [20]. In the exams at 4 years, an additional assessment was done by means of the modified United States Public Health Service (USPHS) criteria [32] and the Visible Plaque Index-VPI and Gingival Bleeding Index-GBI [33]. Each evaluation was performed by a different blind examiner for the type of GIC used in ART and calibrated with the respective intra-examiner correlation coefficients: 1 year (ART Criterion: Kappa=0.81), 2 years (ART Criterion: Kappa=0.83), and 4 years (ART Criterion: Kappa=0.86; Modified USPHS Criteria: Kappa average=0.73; VPI: Kappa=0.79; caries activity: Kappa=1.0).

For the analysis of the general clinical performance of ART, through the success rate among the different GICs, the chi-square test was applied. In addition, the Mann-Whitney test was used to compare each individual clinical criterion between the materials (retention and anatomical shape, integrity and marginal discoloration, color of material, surface roughness and secondary caries), with all tests at the level of significance of 5% (p <0.05). The Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI), as well as caries activity were expressed through frequencies distribution.

Database construction and analysis, and interpretation of results were obtained by using the Statistical Package for the Social Sciences (SPSS), version 19.0.

Inclusion Criteria:

• presence of active carious cavitated lesions;
• least one deciduous molar in each of the different dental quadrants;
• caries of shallow or medium depth, involving only the occlusal surface.

Exclusion Criteria:

• Children who do not allow clinical procedures to be performed.

Each evaluation was performed by a different blind examiner for the type of GIC used in ART Patients did not know what material was being used on their teeth.