Lobene 1991.

Methods	Trial design: parallel (2 arms) Location: New Jersey, USA (type of setting not reported) Number of centres: 1 Recruitment period: not reported Funding source: not reported but some authors associated with Colgate (the manufacturer of the triclosan/copolymer toothpaste)
Participants	Inclusion criteria: history of supragingival calculus formation (identified by participation in a pretest study) Exclusion criteria: not reported Baseline plaque: not reported Baseline gingivitis: not reported Baseline caries: not reported Age at baseline (years): Gp A: mean 48.3 (range 37‐63); Gp B: mean 43.9 (range 22‐65) Gender: Gp A: male 9 (24%), female 28 (76%); Gp B: male 7 (21%), female 26 (79%) Any other details of important prognostic factors: baseline calculus (Volpe‐Manhold Calculus Index ‐ mean total calculus per participant): Gp A: mean 14.67 mm; Gp B: mean 13.45 mm Number randomised: 84 (not reported by group) Number evaluated: 70 (Gp A: 37; Gp B: 33)
Interventions	Comparison: triclosan/copolymer/sodium fluoride versus sodium fluoride Gp A (n = 37 evaluated): twice daily brushing for 1 minute with toothpaste containing 0.3% triclosan, 2% copolymer, 0.243% sodium fluoride; all participants received a baseline "oral prophylaxis" Gp B (n = 33 evaluated): as above but without triclosan and copolymer Duration of treatment: 6 months
Outcomes	Calculus (Volpe‐Manhold Calculus Index), adverse effects; assessed at 3 and 6 months' follow‐up
Notes	Sample size calculation: not reported Adverse effects: none observed
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "The subjects were stratified into two balanced groups" Comment: insufficient information on the method of sequence generation Additional information from correspondence: simple randomisation using random number tables
Allocation concealment (selection bias)	Low risk	Not mentioned Additional information from correspondence: a rigorous allocation procedure was carried out by people not involved in the study and we are satisfied that this was properly concealed from those involved in the study
Blinding of participants (performance bias) All outcomes	Low risk	Quote: "double‐blind" and "The dentifrices were packaged in identical plain white tubes so that neither the subjects nor the dental examiner knew the identity of the dentifrices throughout the study" Comment: use of an identical control toothpaste meant that participants did not know which group they were assigned to
Blinding of outcome assessment (detection bias) All outcomes	Low risk	Quote: "double‐blind" and "The dentifrices were packaged in identical plain white tubes so that neither the subjects nor the dental examiner knew the identity of the dentifrices throughout the study" Comment: the examiner did not know which group the participants they were assessing had been assigned to
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	17% of randomised participants were not included in the final analysis. Attrition was not reported by group and reasons were not given, but authors stated that reasons were not related to the use of either of the toothpastes. However, if the missing participants had higher mean calculus scores in one group than the other, as the attrition rate increased, so would over/understatement of the mean difference
Selective reporting (reporting bias)	Low risk	For a study looking into anticalculus effect, we consider that an appropriate outcome measure was considered and reported in full
Other bias	Low risk	No mention of calibration of outcome assessor so it is unclear whether or not there was a risk of differential diagnostic activity Additional information from correspondence: this study followed a protocol whereby all outcome assessors were highly trained in the indices and procedures used, and inter‐ and intra‐examiner calibration occur where practical. Therefore, we consider that the risk of differential diagnostic activity is low. We were unable to identify any other potential source of bias