Table 6.

Quality classification of the included studies based on objective and comparable criteria with *=patient survey, **=only one tooth per sextant examined, and +=two investigators

Study	Journal	Study design		Measurement tools	Patients		Results		Grade
	Peer review	Randomization	Investigation of established hypotheses	Suitable measuring instrument	Objective comparison of two consumables	Group size > 35	Adequate level of data aggregated	Investigator
[54]	+	−	−	− *	+	+	+	−	4
[55]	+	−	−	+	+	+	+	+ +	6
[56]	+	−	+  +	+	+	−	+	+	7
[57]	+	−	+  +	+	−	−	+	+	6
[58]	+	−	+  +	− *	+	+	+	−	6
[59]	+	−	−	+	+	−	+	+ +	5
[57]	+	−	+  +	+	+	+	+	+	8
[61]	+	−	−	+	+	+	+	+	6
[62]	+	−	−	+	−	−	+	−	3
[20]	+	−	+  +	+	+	−	+	+	7
[63]	+	−	+  +	+	+	−	+	+	7
[64]	+	−	+  +	− *	+	+	+	−	6
[65]	+	−	−	− **	+	+	+	+	5
[20]	+	−	−	+	+	−	+	+	5
[66]	+	−	−	+	+	−	+	+	5
[67]	+	−	+  +	+	+	−	+	+	7
[68]	+	−	−	+	+	−	+	+	5