Randomized clinical trial evaluating proximal retentions on ART restorations

OBJECTIVES: To evaluate the success rates of proximal retentions on ART Class II restorations, in primary molars. METHODS: This study enrolled 187 children aged 3 to 7 years (mean age = 5.53) from a public school 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 (DZ, JD and RV) performed 293 Class II restorations, in primary molars using the ART hand instruments (SSWhite/Duflex; Rio de Janeiro, Brazil) and encapsulated 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 (MH and EP) evaluated the restorations after 6, 12, 24 and 36 months (Kappa intra- and inter-evaluators > 0.80). Data were analyzed by Mann-Whitney, Chi-square and Fisher's Exact tests. RESULTS: The mean dmf-s of the participants was 21.5 (SD= 10.1). The mean time for cleaning the cavity with hand instruments was 5.4 minutes and the restorative time 6.6 minutes; no case needed the application of local anesthesia and the cooperation of children was acceptable with only 6% uncooperative children. Success rates after 6, 12, 24 and 36 months were: for restorations without retentions: 90.3%, 77.2%, 67.7% and 51.6%, respectively, and with retention: 95.9%, 91.8%, 87.8% and 61.0%, respectively. The observed data showed no difference for 6 months (p=0.159) and showed statistically significant differences for 12 (p=0.001), 24 (p<0.001) and 36 months (p<0.001). CONCLUSIONS: Proximal retentive grooves appear to be very promising for the success of ART Class II restorations on primary teeth. Good cooperation rates and short treatment time are important aspects to take into account for future public health interventions.