Table 9. Comparison between chronological age and dental age estimated using Bedek et al., 4- teeth formulae in boys and girls.

Age Groups (n)	Mean (SD)			95% CI of age difference	t statistics (df)	p-value
	Chronological Age (CA)	Dental Age (DA)	DA-CA (SE)
Boys
7- 7.9 (7)	7.35 (0.29)	6.54 (0.41)	-0.81 (0.17)	-1.24 to -0.38	-4.63 (6)	0.004*
8- 8.9 (14)	8.51 (0.29)	7.26 (0.82)	-1.25 (0.24)	-1.77 to -0.72	-5.15 (13)	0.000*
9- 9.9 (24)	9.37 (0.26)	8.48 (1.44)	-0.88 (0.3)	-1.51 to -0.26	-2.94 (23)	0.007*
10- 10.9 (28)	10.39 (0.26)	9.69 (0.9)	-0.7 (0.16)	-1.03 to -0.37	-4 35 (27)	0.000*
11- 11.9 (36)	11.4 (0.29)	11.22 (1.07)	-0.17 (0.17)	-0.52 to 0.17	-1.01 (35)	0.319
12- 12.9 (49)	12.47 (0.27)	11.84 (1.36)	-0.62 (0.19)	-1.01 to -0.24	-3.27 (48)	0.002*
13- 13.9 (53)	13.51 (0.29)	13.03 (1.25)	-0.46 (0.15)	-0.78 to -0.15	-3.01 (52)	0.004*
14- 14.9 (64)	14.44 (0.29)	13.84 (0.93)	-0.59 (0.11)	-0.82 to -0.37	-5.33 (63)	0.000*
7- 14.9 (275)	12.17 (2.01)	11.57 (2.38)	-0.59 (0.06)	-0.72 to -0.46	-8.90 (274)	0.000*
Girls
7- 7.9 (10)	7.52 (0.31)	8.06 (1.31)	0.54 (0.39)	-0.34 to 1.43	1.37 (9)	0.201
8- 8.9 (16)	8.34 (0.25)	7.96 (0.78)	-0.37 (0.22)	-0.86 to 0.11	-1.67 (15)	0.116
9- 9.9 (22)	9.45 (0.25)	9.17 (1.8)	-0.27 (0.38)	-1.07 to 0.51	-0.72 (21)	0.474
10- 10.9 (37)	10.42 (0.25)	9.82 (1.26)	-0.6 (0.19)	-1.01 to -0.19	-3.02 (36)	0.005*
11- 11.9 (94)	11.41 (0.28)	10.72 (1.23)	-0.62 (0.12)	-0.88 to -0.37	-4.89 (93)	0.000*
12- 12.9 (79)	12.43 (0.28)	12.01 (1.19)	-0.43 (0.12)	-0.68 to -0.17	-3.31 (78)	0.001*
13- 13.9 (53)	13.46 (0.29)	13.25 (1.03)	-0.21 (0.14)	-0.49 to 0.07	-1.49 (52)	0.142
14- 14.9 (64)	14.46 (0.23)	14.11 (0.81)	-0.34 (0.09)	-0.54 to -0.15	-3.59 (63)	0.001*
7- 14.9 (375)	11.99 (1.8)	11.57 (2.13)	-0.41 (0.05)	-0.53 to -0.29	-6.91 (374)	0.000*

*Statistically significant (p<0.05); SD Standard deviation; SE Standard error; df degree of freedom