Table 4. Mean difference in years between estimated dental age and chronological ages by periodontal ligament visibility category.

	Side	PLV	Mean	SD	Significance	Absolute mean	N
Males	left	0	1.02	3.86	NS	3.26	5
		1	1.63	3.11	NS	2.66	7
		2	9.32	3.48	0.000	9.32	25
		3	8.01	5.34	0.000	9.03	22
	right	0	-1.00	5.85	NS	4.09	3
		1	3.83	0.89	0.003	3.83	4
		2	7.60	6.87	0.000	9.64	26
		3	9.58	4.32	0.000	9.64	23
Females	left	0	-0.49	2.66	NS	2.07	11
		1	2.85	2.21	0.001	3.10	12
		2	9.84	2.59	0.000	9.84	33
		3	9.28	8.22	0.002	11.53	13
	right	0	2.80	1.10	0.048	2.80	3
		1	3.69	1.33	0.000	3.69	11
		2	8.67	6.31	0.000	10.16	30
		3	12.09	7.03	0.000	13.59	20