Lo 2006.

Methods	Design: cluster, parallel RCT (an individual is a cluster) Number of participant: 103 Setting: nursing homes Country: China Unit of randomisation: participant Unit of analysis: tooth Follow‐up: 6 and 12 months Dropout: 25.2% after 12 months
Participants	Number randomised (participants): 103 participants/162 teeth (78 ART group and 84 CT group) Number analysed: 77 participants/122 teeth Age mean and SD (range): 78.6 years Sex: female 72 (69.9%), male 31 (30.1%) Average DMFT score: 1.0 Dentition: permanent Type of caries lesion: root caries Inclusion criteria: > 60 years of age, having basic self‐care ability, and with root caries lesions ≥ 1 mm in depth Exclusion criteria: lesions involving or judged to be very close to the dental pulp
Interventions	Two treatment arms: Group 1: ART approach + H‐GIC Group 2: CT + RM‐GIC with anaesthesia The ART technique consisted of removing all the soft dentin only with hand instruments. Cotton rolls and gingival retraction cord were used when necessary for field isolation and moisture control. Cavity was conditioned for 10‐15 s. The prepared cavity was restored with a high‐strength chemically cured glass‐ionomer material (Ketac Molar, 3M ESPE, Seefeld, Germany). A clear cellulose matrix was used to build up the contour of the root. CT used local anaesthesia when required. Cotton rolls and gingival retraction cord were used for field isolation and moisture control. Decayed tooth tissues were removed by means of dental burs until the floor and walls of the cavity were found to be hard. The prepared cavity was conditioned with polyacrylic acid for 10‐15 seconds, washed, dried, and restored with a resin modified glass‐ionomer material (Fuji II LC, GC Corporation, Tokyo, Japan) The interventions were conducted by 1 dentist.
Outcomes	Success and survival rate assessed by USPHS criteria and ART criteria. Sound restorations or restorations with marginal defect or wear < 0.5 mm, measured by the ball tip of a CPI periodontal probe, were classified as having survived.
Notes	Funding: Hong Kong Research Grants Council (Ref. HKU 7244/02M) Trial register number: not reported Sample size calculated Intraexaminer reproducibility evaluated but not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "We tossed a coin to allocate the selected lesions randomly to receive one of the two study treatments" "For patients who had 2 root‐caries lesions, both types of treatment were provided" "The treatment assignment procedure was repeated if there were more than 2 lesions in a subject"
Allocation concealment (selection bias)	Unclear risk	Comments: not reported
Blinding of participants and personnel (performance bias) ‐ participant	High risk	Comments: no information provided, but the participants could tell whether manual or rotary instruments were used
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: "Restorations was assessed at six‐month intervals by a dentist who was not involved in the provision of the treatments, and who did not know which technique had been used in placing the restoration” “Blindness was possible because tooth‐colored glass‐ionomer material was used in both techniques, and the restorations had similar appearances."
Incomplete outcome data (attrition bias) All outcomes	High risk	Quote: "The reasons for dropout were that the patients had died, were too ill to be examined, or were not at the home on the examination day" Comments: while the causes of dropout are indicated, the loss was high (25%)
Selective reporting (reporting bias)	Low risk	Comments: all outcomes listed in the methods sections were included.
Other bias	High risk	Comments: the analysis did not consider the paired data.