Randomized Clinical Trial for Class II ART Restorations in Primary Molars: 24 Months Results

Untreated dental caries in primary teeth is a public health issue worldwide and its management is based on Minimal Intervention Dentistry guidelines: Selective carious tissue removal, preservation of dental tissues and the use of biocompatible materials. Objective: To evaluate the survival rate adapting the Atraumatic Restoration Technique (ART) through mechanical retentions in Class II cavities in primary molars. Methods: This study enrolled 187 children with good general health aged 3 to 7 years (mean 5.53) from two public schools located in a low socio-economical community in Lima, Peru. Children with good general health, whose parents signed the informed consent form, were included in the study. Three trained operators performed 293 Class II restorations in primary molars using the ART hand instruments (SSWhite/Duflex; Rio de Janeiro, Brazil) and encapsulated high viscosity glass ionomer cement EQUIA Fil (GC Corporation; Tokyo, Japan). The children were referred to the San Martin de Porres University – Dental School Clinic for additional restorative care. Two calibrated examiners evaluated the restorations after 6, 12 and 24 months (Kappa intra- and inter-evaluators > 0.80). Data were analyzed by Mann-Whitney, Chi-square and Fisher’s Exact tests. Results: The mean dmfs (decayed, missing, filled surfaces) of the participants was 21.5 (SD= 10.1). The mean time for cleaning the cavity was 5.4 minutes and the restorative time, 6.6 minutes; no local anesthesia was needed for any case and the cooperation of children was mostly acceptable (94%). Success rates after 6, 12 and 24 months were: 90.3%, 77.2% and 67.7%, respectively for restorations without retention; and: 95.9%, 91.8% and 87.8%, respectively with retention. No statistically significant differences were observed for 6 months (p=0.08), but clearly detected for 12 and 24 months (p<0.001) Conclusion: Proximal retentive grooves appear to be very promising for improving ART Class II restorations on primary teeth. Good cooperation rates and short treatment time are important aspects to consider for public health interventions, as well as the feasibility for working with ART in schools.