2. Full‐mouth scaling versus control: change in clinical attachment level.

Tooth type: single‐ or multi‐rooted, or both	Baseline pocket depth (mm)	Time (months)	Number of studies (participants)	Mean difference (95% CI) (random‐effects meta‐analysis)	Heterogeneity
Both	5–6	3/4	4 (111)	0.02 (–0.19, 0.23); P = 0.85	P = 0.90; I² = 0%
Both	> 6	3/4	5 (127)	0.09 (–0.22, 0.41); P = 0.57	P = 1.00; I² = 0%
Both	5–6	6/8	3 (89)	0.22 (–0.05, 0.49); P = 0.11	P = 0.87; I² = 0%
Both	> 6	6/8	4 (105)	0.05 (–0.64, 0.74); P = 0.89	P = 0.005; I² = 77%
Single‐rooted	5–6	3/4	1 (16)	0.41 (–0.00, 0.82); P = 0.05	Not applicable
Single‐rooted	> 6	3/4	0 (0)	Not estimable	Not applicable
Single‐rooted	5–6	6/8	2 (40)	0.04 (–0.19, 0.27); P = 0.71	P = 0.50; I² = 0%
Single‐rooted	> 6	6/8	1 (24)	0.47 (–0.37, 1.31); P = 0.27	Not applicable
Multi‐rooted	5–6	3/4	1 (16)	1.11 (0.45, 1.77); P = 0.0009	Not applicable
Multi‐rooted	> 6	3/4	0 (0)	Not estimable	Not applicable
Multi‐rooted	5–6	6/8	2 (40)	0.00 (–0.34, 0.34); P = 1.00	P = 0.19; I² = 41%
Multi‐rooted	> 6	6/8	1 (24)	0.38 (–0.28, 1.04); P = 0.26	Not applicable

CI: confidence interval.