 The aim of this, two-arm, parallel group, patient-randomised controlled, superiority trial is to evaluate the survival rate of approximal Atraumatic Restorative Treatment ART restorations compared to the Hall Technique HT placed in a school setting. The investigators will recruit 120 schoolchildren 6-8 years with at least one occlusal-proximal carious lesion in primary molar. They will be randomized and treated following best-practice protocols to either receive an ART restoration using the high-viscosity glass ionomer cement EQUIA Forte, capsules, GC Corp. or a preformed metal crown placed using the HT 3M ESPE cemented with glass ionomer luting cement Fuji I Capsules, GC Corp.. Baseline measures and outcome data at reviews over a three year period will be assessed through participant report, clinical examination and parent report questionnaires. 