Table 1.

Estimated mean, and percentage change in the apical diameter (mm), root thickness (mm), root length (mm), and root radiographic area (mm) in different follow-up periods

Time variable	Estimated mean (standard error) in AD and P	Percentage change from the baseline in AD	Estimated mean (standard error) in RT and P	Percentage change from the baseline in RT	Estimated mean (standard error) in RL and P	Percentage change from the baseline in RL	Estimated mean (standard error) in RRA and P	Percentage change from the baseline in RRA
Preoperative	1.189 (0.135)		2.124 (0.134)		12.328 (0.681)		48.54 (3.57)
0.5-1 year	1.077 (0.135) P=0.264	-9.53±7.76	2.363 (0.134) P=0.003	12.08±8.92	12.695 (0.681) P=0.003	3.23±2.19	51.98 (3.57) P=0.003	7.16±2.41
1-2 years	1.025 (0.138) P=0.268	-14.79±6.54	2.470 (0.138) P=0.003	18.82±11.83	12.937 (0.682) P=0.001	6.12±3.33	53.35 (3.59) P=0.001	12.42±5.67
2-3 years	0.917 (0.135) P=0.037	-23.56±15.7	2.657 (0.134) P<0.001	26.09±13.14	13.267 (0.681) P<0.001	8.23±4.94	55.19 (3.57) P=0.001	15.41±11.24
4-5 years	0.720 (0.137) P=0.001	-30.96±16.61	2.934 (0.137) P<0.001	44.89±20.92	13.746 (0.682) P<0.001	13.18±5.42	59.36 (3.59) P<0.001	26.35±25.29

AD: Apical diameter, RT: Root thickness, RL: Root length, RRA: Root radiographic area