ART and Hall Technique for Management of Occlusal-proximal Caries in Primary Molars

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 (5-10 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.

The selected children will be randomly allocated into 2 groups. The control group will comprise cavities treated by ART, following the protocol proposed by Frencken and Holmgren (1999), while the experimental group will comprise cavities treated by HT, according to the guideline published by Innes and Evans (2011). The allocation of patients in each group will be carried out by a random list generated by a specific computer program. To ensure the allocation concealment, the sequence generated by randomization will be distributed in opaque, sealed envelopes, which will be opened by the operator during the treatment, only after the patient is ready to receive treatment.

Operators will be two undergraduate students in dentistry and one experienced specialist in pediatric dentistry that will be trained on how to prepare and fill the cavities according to the original procedures of ART (Frencken and Holmgren, 1999) and also according to HT (Innes and Evans, 2011). The training will include a lecture about the techniques used in this study, as well as a workshop held in the laboratory for students to train handling and application of treatments to be tested. They will also undergo a week of training with patients, to apply the different techniques before starting the study, the latter phase held at the Faculty of Dentistry, University of São Paulo, under the supervision of an experienced dentist in ART and HT.

Each child will be allocated for one of the operators with the aid of a random list. All treatments will be performed on the school premises, in field conditions without the use of dental chair or other facilities from a clinical environment.

Eligibility Criteria:
Inclusion Criteria:

* children aged between 5 and 10 years
* cooperative behavior
* presenting good health conditions
* whose parents or legal guardians accept and sign the consent form
* with at least one occluso-proximal lesion in primary molar
* only occlusal-proximal surfaces with caries lesions with dentin involvement
* cavities accessible to hand instruments used in ART
* absence of fistula or abscess near the selected tooth
* absence of pulp exposure in the selected tooth
* absence of mobility in the selected tooth
* cavity size in the selected tooth not be bigger than 2.0 mm in the mesial-distal and 2.5 in the occlusal-cervical and bucco-lingual directions.

Exclusion Criteria:

* children younger than 5 years and older than 10
* non-cooperative behavior
* without good health conditions
* whose parents or legal guardians did not accepted and signed the consent form
* without any occluso-proximal lesion in primary molar
* caries in the selected tooth reaching other surfaces (than occlusal-proximal surface)
* occlusal-proximal surface with caries without dentin involvement
* cavities not accessible to hand instruments
* fistula or abscess near the selected tooth
* pulp exposure in the selected tooth
* mobility in the selected tooth
* cavity size bigger than 2.0 mm in the mesial-distal and 2.5 in the occlusal-cervical and - bucco-lingual directions.