Table 3. Intra-group comparisons of clinical outcomes at various time intervals for test teeth.

Variables	Time intervals	Treatment groups
		Group 1			Group 2			Group 3
		Mean difference±SD	t value	P value	Mean difference±SD	t value	P value	Mean difference±SD	t value	P value
PPD	Baseline vs. 8 weeks	1.78±0.63	10.91	<0.001	2.08±0.49	16.36	<0.001	1.88±0.53	13.24	<0.001
	Baseline vs. 12 weeks	1.68±0.55	11.88	<0.001	2.03±0.44	17.93	<0.001	1.74±0.48	13.48	<0.001
	Baseline vs. 24 weeks	1.64±0.58	10.86	<0.001	1.86±0.45	16.04	<0.001	1.72±0.45	14.42	<0.001
	8 weeks vs. 12 weeks	−0.09±0.31	1.15	NS	−0.04±0.16	1.02	NS	−0.15±0.37	−1.47	NS
	8 weeks vs. 24 weeks	−0.14±0.24	2.28	0.039	−0.21±0.43	1.92	NS	−0.17±0.34	1.80	NS
	12 weeks vs. 24 weeks	−0.05±0.25	0.72	NS	−0.17±0.36	1.87	NS	−0.02±0.38	0.18	NS
CAL	Baseline vs. 8 weeks	1.26±0.54	8.82	<0.001	1.54±0.99	6.04	<0.001	1.67±0.91	7.11	<0.001
	Baseline vs. 12 weeks	1.25±0.52	8.91	<0.001	1.47±0.52	10.83	<0.001	1.64±0.73	8.71	<0.001
	Baseline vs. 24 weeks	1.13±0.68	6.19	<0.001	1.45±0.45	12.45	<0.001	1.56±0.64	9.45	<0.001
	8 weeks vs. 12 weeks	−0.01±0.35	−0.15	NS	−0.08±0.87	−0.34	NS	−0.04±0.96	−0.15	NS
	8 weeks vs. 24 weeks	−0.13±0.60	−0.82	NS	−0.09±0.88	−0.40	NS	−0.11±0.91	−0.48	NS
	12 weeks vs. 24 weeks	−0.12±0.46	−0.96	NS	−0.01±0.22	−0.25	NS	−0.08±0.16	−1.82	NS
PI	Baseline vs. 8 weeks	1.60±0.27	22.07	<0.001	1.55±0.38	15.56	<0.001	1.84±0.47	14.73	<0.001
	Baseline vs. 12 weeks	1.56±0.43	12.41	<0.001	1.48±0.35	16.57	<0.001	1.82±0.48	14.69	<0.001
	Baseline vs. 24 weeks	1.38±0.25	25.15	<0.001	1.37±0.39	15.32	<0.001	1.74±0.45	13.88	<0.001
	8 weeks vs. 12 weeks	−0.04±0.35	−0.85	NS	−0.07±0.21	2.17	0.048	−0.02±0.19	0.74	NS
	8 weeks vs. 24 weeks	−0.22±0.21	2.19	0.036	−0.18±0.18	4.04	0.001	−0.10±0.27	1.65	NS
	12 weeks vs. 24 weeks	−0.18±0.35	2.05	0.041	−0.11±0.22	3.01	0.004	−0.08±0.21	2.06	NS
GI	Baseline vs. 8 weeks	0.45±0.36	4.89	<0.001	0.59±0.32	7.14	<0.001	0.77±0.24	12.22	<0.001
	Baseline vs. 12 weeks	0.40±0.34	4.63	<0.001	0.56±0.32	6.20	<0.001	0.72±0.21	12.52	<0.001
	Baseline vs. 24 weeks	0.38±0.33	7.18	<0.001	0.53±0.17	9.62	<0.001	0.64±0.25	9.64	<0.001
	8 weeks vs. 12 weeks	0.05±0.11	1.25	NS	0.02±0.27	1.01	NS	−0.05±0.12	−1.57	NS
	8 weeks vs. 24 weeks	0.07±0.28	1.42	NS	0.05±0.27	1.14	NS	0.13±0.17	0.72	NS
	12 weeks vs. 24 weeks	0.02±0.24	1.39	NS	0.03±0.22	1.02	NS	0.08±0.08	1.05	NS

Significance of differences between groups: P>0.05: NS; P<0.05: significant (bold).

SRP: scaling and root planing, SRP+P: scaling and root planing+single application of probiotic, SRP+PPP: scaling and root planing+incremental application of probiotic, PPD: probing pocket depth, CAL: clinical attachment level, PI: plaque index, GI: gingival index, NS: not significant.