Accuracy assessment of dental age estimation with the Willems, Demirjian and Nolla methods in Spanish children: Comparative cross-sectional study

Table 4 Results of the calculation of the dental age with the Demirjian method. The Wilcoxon test for paired data was applied by age groups and sex to compare the chronological age and dental age

Age groups	n	CA		DA Demirjian		p-value	CA-DA	Diff.SD	Trend
Age groups	n	mean	SD	mean	SD	p-value	CA-DA	Diff.SD	Trend
Girls
4-6.9	59	6.46	0.48	7.48	0.82	0.000	-1.02	0.65	O
7-7.9	65	7.50	0.30	8.20	0.83	0.000	-0.69	0.78	O
8-8.9	69	8.45	0.28	8.92	0.79	0.000	-0.48	0.76	O
9-10.9	67	9.97	0.57	10.77	1.34	0.000	-0.80	1.18	O
11-13.9	42	12.14	0.63	12.84	1.28	0.000	-0.70	1.21	O
Total	302
Boys
4-6.9	63	6.40	0.55	7.28	1.09	0.000	-0.88	0.78	O
7-7.9	54	7.60	0.28	8.43	1.04	0.000	-0.84	0.99	O
8-8.9	67	8.45	0.29	9.03	0.87	0.000	-0.57	0.76	O
9-10.9	63	9.89	0.58	10.47	1.31	0.001	-0.59	1.63	O
11-13.9	55	12.15	0.60	12.65	1.00	0.000	-0.50	1.00	O
Total	302