Table 1. Clinical and microbial variables for the placebo and antibiotic group at baseline and 2 months after therapy.

	Placebo (n = 47)			Antibiotic (n = 42)
	Baseline	2 months after therapy	P-value	Baseline	2 months after therapy	P-value
Clinical variables
%PPD5mm#	17.9 ± 12.0	10.4± 9.5	<0.001	20.9 ± 14.0	7.7 ± 6.9	<0.001
	14 (11, 21)	8 (5, 13)		19 (12, 25)	6 (2, 13)
%BOP#	34.4 ± 18.6	18.0 ± 13.2	<0.001	41.5 ± 22.8	13.7 ± 11.9	<0.001
	27 (20, 52)	15 (7, 27)		37 (28, 58)	10 (5, 20)
%RAL1.3mm#		3.8 ± 4.1			3.9 ± 5.0
		2 (1, 6)			2 (1, 5)
Microbiome variables
Richness	103.21 ± 40.57	98.80 ± 41.93	0.122	108.49 ± 30.85	83.89 ± 29.69	<0.001
	99 (86, 128)	94 (68, 126)		112 (85, 131)	81 (63, 103)
Evenness#	0.73 ± 0.07	0.73 ± 0.07	0.863	0.72 ± 0.05	0.73 ± 0.08	0.214
	0.75 (0.69, 0.78)	0.75 (0.71, 0.78)		0.73 (0.69, 0.75)	0.74 (0.70, 0.77)
Diversity#	3.32 ± 0.54	3.30 ± 0.56	0.822	3.34 ± 0.41	3.20 ± 0.51	0.057
	3.33 (3.02, 3.67)	3.30 (2.99, 3.67)		3.45 (3.12, 3.61)	3.30 (3.02, 3.50)
Dissimilarity#	0.69 ± 0.05	0.70 ± 0.05	0.193	0.69 ± 0.05	0.74 ± 0.05	<0.001
	0.69 (0.66, 0.72)	0.69 (0.67, 0.73)		0.67 (0.66, 0.71)	0.73 (0.71, 0.75)

%PPD5mm, percentage of tooth sites with pocket depth ≥5 mm; %BOP, percentage of tooth sites with bleeding on probing; %RAL1.3mm, percentage of tooth sites with further relative attachment loss of ≥1.3mm between baseline and 2 months after therapy; Richness, number of aRSVs; Evenness, Pielou index; Diversity, Shannon-index; Dissimilarity, Bray-Curtis index. All variables are shown as mean ± standard deviation and median (25% quantile, 75% quantile). P-values are derived from Wilcoxon signed-rank tests comparing the variables between before and after treatment within each group.

^# Skewed distributed variables.