RESUMEN
BACKGROUND: Atraumatic restorative treatment (ART) has the advantages of reducing pain and fear and of being more cost-effective than the traditional approach. AIM: The aim of this study was to investigate the survival of ART class I and II restorations in primary molars at 2 years. DESIGN: The sample consisted of 190 restorations and placed in 155 children 6-7 years old of both genders. The treatment was performed by two final-year dental students. All patients were treated in a completely supine position on tables available in the schools. The restorations were evaluated at 1, 12, and 24 months. RESULTS: The best results were found for class I in each period of follow-up. After 1 month, the success of class I restorations was 94.6% and class II restorations 70.1%. After 12 months, the success rate was 50.6% for class I and 15.2% for class II. The most frequent failure characteristics were totally or partially lost and gross marginal defect. CONCLUSIONS: The rate of success of restorations using the ART approach was significantly lower for class II.