6. Studies with a gingival inflammation outcome not included in meta‐analyses.

Time	Study ID	Comparison	Index	CHX mean (SD)	Control mean (SD)	Total n	Notes
4 to 6 weeks	Anauate‐Netto 2014	CHX 0.12% vs placebo	PBS	0.9 (0.6)	0.7 (0.4)	40	Did not report GI. Quote: "..no statistically significant differences were detected among groups"
7 to 12 weeks	Anderson 1997	CHX 0.12% vs placebo	GI	0.345	0.895	28	Reported mean GI by surface + SD. No overall SD. We calculated overall mean. Quote: "The means of the …gingival indices did not show any significant differences (P<0.05) 1 or 2 months after baseline. However there were significant differences (P<0.05) in the changes recorded at 30 and 60 days at all sites in…..the experimental group"
	de la Rosa 1888b	CHX 0.12% vs placebo	PMGI severity (mean score of all sites graded)	0.1413	0.2902	92	Did not report GI or a SD. Quote: "..the effect of the chlorhexidine rinse on the occurrence and severity of gingivitis amounted to a 51% reduction of the disease compared to the placebo rinse…differences were statistically significant"
	de la Rosa 1988a	CHX 0.12% vs placebo	PMGI severity (mean score of all sites graded)	0.2892	0.4526	99	Did not report GI or a SD. Quote: "..the gingivitis reductions were 34% and 36% for occurrence and severity respectively…differences were statistically significant"
	Eaton 1997	CHX 0.12% vs placebo	mGI	0.42 (0.383)	0.55 (0.382)	98	Did not report GI. Quote: "..the pooled mean mGI score improved by 25% from 0.56 at baseline to 0.42 at 12 weeks in the ChD (CHX) group but showed no change (0.54 to 0.55) in the placebo group"
	Ferretti 1987	CHX 0.12% vs placebo	PMGI	0.8	1.94	33	Did not report GI and SD depicted in graph but not reported. Quote: "Significant reductions in …gingivitis scores were seen on days 33 (P<0.0001) and 60… (P<0.001) for those patients using chlorhexidine rinse"
	Segreto 1986	0.2% vs 0.12% vs placebo	GI	0.4112/0.3640	0.5039	454	Did not report a SD. Quote: "Gingivitis severity by the GI method was… significantly lower at 3 months for both chlorhexidine groups compared to the placebo group. Differences ranged from 28‐46% and averaged 37% for the 0.12% group. Differences ranged from 18‐40% for the 0.20% group and averaged 29%"
	Weitz 1992	CHX 0.12% vs placebo	GI	1.69	1.86	36	Did not report a SD. Quote: "…the active (CHX) groups had significantly lower… gingivitis scores than the respective control groups. Overall, the active group had a 10.27% reduction in the gingival index…compared to insignificant changes in the control groups"
6 months	Fine 1985	CHX+OH vs OH	Not clear. Quote: "a gingival inflammation Index"	NR	NR	83	Outcomes reported in graphs which are difficult to decipher. Quote: "Whilst there was a general improvement in all… groups of patients, no one group was statistically significantly different from the other…"
	Hoffmann 2001	CHX 0.1%, CHX 0.06%, CHX 0.06%+F vs control	GI	Median 0.15/0.29/0.34	Median 0.45	58	No SD. At 3 months "..only the 0.1% CHX was different from the control". At 6 months "…the 0.1% CHX showed significant differences…in the GI…when compared to the 0.06% CHX/F" (P = 0.043)
	Overholser 1990	CHX 0.12% vs control	mGI	0.81 (SE 0.065)	1.166 (SE 0.063)	83	Did not report a SD. Quote: "PX (CHX) inhibited gingivitis development by 26.8% (P<0.001) at 3 months and by 30.5% (P<0.001) at 6 months, compared to the control"

CHX = chlorhexidine; F = fluoride; NR = not reported; OH = oral hygiene; SD = standard deviation; SE = standard error.

Total n is the number of participants analysed in the study arms relevant to the review.

PBS (Papillary Bleeding Score, Loesche 1979) is measured on a 0‐5 increasing scale.

GI (Gingival Index, Löe 1967; Löe and Silness 1963) is measured on a 0‐3 increasing scale.

PMGI (Papillary Marginal Gingivitis Index, de la Rosa and Sturzenberger 1976) is measured on a 0‐3 increasing scale.

mGI (modified Gingival Index, Lobene 1986) is measured on a 0‐4 increasing scale.