Photobiomodulation by a 635nm Diode Laser on Peri-Implant Bone: Primary and Secondary Stability and Bone Density Analysis—A Randomized Clinical Trial

Table 3

Mean grayscale values of 2 groups at cervical level.

Period	Laser	Std	Control	Std	t-value	df	p-value
Baseline	1240.75	78.97	1283.42	66.66	-1.43	22	0.1667
4 weeks	755.92	34.51	726.83	24.18	2.39	22	0.0258
12 weeks	801.75	27.47	783.25	34.92	1.44	22	0.1633

Std: standard deviation.
df: degree of freedom.