Table 5. Comparison of chronological and D4-A dental ages by gender and age group.

Gender	Age group (years)	N	CA	DA	DA-CA	p value#
			Mean ± SD (years)
GIRLS	5	24	5.46 ± 0.33	6.87 ± 0.25	1.69 ± 1.21	< 0.001
	6	39	6.57 ± 0.32	7.54 ± 0.14	1.05 ± 0.68	< 0.001
	7	46	7.52 ± 0.26	7.73 ± 0.14	0.77 ± 1.05	0.122
	8	50	8.51 ± 0.31	8.18 ± 0.12	0.75 ± 0.64	< 0.001
	9	55	9.48 ± 0.30	8.90 ± 0.20	1.36 ± 1.43	< 0.001
	10	55	10.55 ± 0.32	10.04 ± 0.24	1.21 ± 1.18	0.016
	11	40	11.44 ± 0.32	11.26 ± 0.32	1.38 ± 1.27	0.595
	12	55	12.49 ± 0.32	11.52 ± 0.31	1.58 ± 1.18	0.021
	13	57	13.46 ± 0.30	11.57 ± 0.38	1.40 ± 0.93	0.002
	14	59	14.48 ± 0.28	10.11 ± 0.40	1.22 ± 0.99	< 0.001
	15	21	15.48 ± 0.27	9.02 ± 0.57	0.60 ± 0.37	< 0.001
	Total	501	10.68 ± 2.87	9.57 ± 0.11	1.20 ± 1.10	< 0.001
BOYS	5	23	5.56 ± 0.29	7.21 ± 0.11	1.67 ± 0.57	< 0.001
	6	40	6.52 ± 0.31	7.75 ± 0.16	1.31 ± 1.10	< 0.001
	7	58	7.48 ± 0.29	8.01 ± 0.08	0.70 ± 0.73	< 0.001
	8	58	8.47 ± 0.29	8.76 ± 0.15	1.14 ± 1.11	0.343
	9	78	9.46 ± 0.28	9.23 ± 0.18	1.25 ± 1.18	0.002
	10	100	10.45 ± 0.29	10.40 ± 0.17	1.37 ± 1.13	0.137
	11	82	11.51 ± 0.30	11.84 ± 0.22	1.37 ± 1.22	0.414
	12	91	12.44 ± 0.30	13.04 ± 0.21	1.50 ± 1.17	0.007
	13	82	13.41 ± 0.31	14.11 ± 0.21	1.57 ± 1.07	< 0.001
	14	58	14.47 ± 0.31	15.61 ± 0.11	1.30 ± 0.57	< 0.001
	15	29	15.24 ± 0.25	15.65 ± 0.21	0.96 ± 0.87	0.002
	Total	699	10.81 ± 2.60	11.28 ± 0.11	1.31 ± 1.07	< 0.001
Total sample		1200	10.75 ± 2.72	10.56 ± 0.09	1.26 ± 1.08	0.322

^#Wilcoxon Signed Rank test: p ≤ 0.05 = significant