Yu 2004.

Methods	Design: cluster split‐mouth RCT Number of participants: 60 Setting: school dental clinic Country: China Unit of randomisation: tooth Unit of analysis: tooth pairs Follow‐up: 6, 12 and 24 months Dropout: 33.3% and 55% after 12 and 24 months
Participants	Number randomised (participants): 60 children/167 teeth (72 ART group and 95 CT group) Number analysed: 27 child/69 teeth Age mean and SD (range): 7.4 SD 1.24 (7‐9 years) Gender: female 33 (55%), male 27 (45%) Average dmft score: not reported Dentition: primary Type of caries lesion: simple and multiple surface caries lesion Inclusion criteria: healthy children with ≥ 1 pair of primary molars with caries lesions of similar size and class Exclusion criteria: not reported
Interventions	Study has 9 arms: Group 1: ART approach in class I caries lesion + H‐GIC (Fuji IX) Group 2: ART approach in class I caries lesion + H‐GIC (Ketac‐Molar) Group 3: ART approach in class II caries lesion + H‐GIC (Fuji IX) Group 4: ART approach in class II caries lesion + H‐GIC (Ketac‐Molar) Group 5: CT in class I caries lesion + H‐GIC (Fuji IX) Group 6: CT in class I caries lesion + H‐GIC (Ketac‐Molar) Group 7: CT in class II caries lesion + H‐GIC (Fuji IX) Group 8: CT in class II caries lesion + H‐GIC (Ketac‐Molar) Group 9: CT in class I caries lesion + amalgam The ART cavity preparation method followed the directions given in the ART technique manual, ensuring removal of all softened carious dentin at the dentinoenamel junction. Strong, unsupported enamel cusps were left intact where access for caries removal was deemed satisfactory. Bases were not used with any of the restorations. The cavities for CT were prepared with conventional rotatory instruments. The cavities were not used with any of the restorations. The GICs were coated with a varnish after placement, and the amalgam restorations were left unpolished. No local anaesthesia was used in either group. The interventions were conducted by 2 dentists.
Outcomes	Cumulative success rate assessed by ART criteria at 6, 12 and 24 months. Scores 2, 3, 4 and 5 were considered as failure (2 = restoration present, defect at margin and/or surface wear of 0.5 to 1.0 mm; 3 = present, gross defect at margin and/or surface wear of > 1.0 mm; 4 = not present, restoration has disappeared; 5 = not present, because other treatment has been performed. Recurrent caries was determined through cavitation and softened dentin at the margin of the restoration.
Notes	Funding: supply of commercial materials and some financial assistance was provided by ESPE Dental Medizin GmbH and by GC International Corp Trial register number not reported Sample size not calculated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: “Treatments were assigned randomly to one of nine groups” Comments: how this was done is not described.
Allocation concealment (selection bias)	Unclear risk	Comments: not reported
Blinding of participants and personnel (performance bias) ‐ participant	High risk	Comments: participants aware of different treatments
Blinding of participants and personnel (performance bias) ‐ operator All outcomes	High risk	Comments: blinding not possible ‐ operator knew the intervention
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "The assessment were recorded by a researcher who did not performed any treatment"
Incomplete outcome data (attrition bias) All outcomes	High risk	Comments: loss to follow‐up was high at 2 years (55%).
Selective reporting (reporting bias)	Low risk	Comments: all prespecified outcomes reported
Other bias	High risk	Comments: the analysis did not consider the paired data.

ART: atraumatic restorative treatment; CPI: Community Periodontal Index; CT: conventional treatment; dmft: decayed, missing and filled primary teeth); DMFT: decayed, missing and filled permanent teeth; GIC: glass ionomer cement; H‐GIC: high‐viscosity glass ionomer cement; RCT: randomised controlled trial; RM‐GIC: resin‐modified glass‐ionomer cement; USPHS: US Public Health Service