Original meta-analysis Trim and fill analysis
Outcome Mean difference P-value Mean difference Studies trimmed/
total studies 		Egger regression
P-level
95% CI 95% CI
PD reduction (total) 0.42 (0.27; 0.58) < 0.00001 0.42 (0.27; 0.58) 0/6 0.5
PD reduction (moderate) 1.07 (0.61; 2.8) 0.002 1.07 (0.61; 2.8) 0/4 0.1
PD reduction (sever) 1.44 (0.55; 2.33) 0.002 1.44 (0.55; 2.33) 0/4 0.1
CAL gain (total) 1.04 (0.2; 1.88) 0.01 1.04 (0.2; 1.88) 0/6 0.07
CAL gain (moderate) 1.33 (0.33; 2.34) 0.009 1.33 (0.33; 2.34) 0/4 0.7
CAL gain (sever) 1.47 (0.26; 2.68) 0.02 1.47 (0.29; 2.68) 0/4 0.01
CAL gain (Sgolastra et al. [27]) 0.42 (0.23; 0.61) < 0.0001 0.37 (0.19; 0.54) 1/6 0.72

PD = probing depth; CAL = clinical attachment level; CI = confidence interval.