Gingival Depigmentation Using Diode 980 nm and Erbium-YAG 2940 nm Lasers: A Split-Mouth Clinical Comparative Study

Table 1

Er:YAG 2940 nm and diode 980 nm laser parameters and specifications.

Specification	Laser type
	Er:YAG 2940 nm	Diode 980 nm
Laser manufacturer	LAMBDA Dr. Smile	LAMBDA Dr. Smile
Model	Pulser	Wiser
Delivery system	Noncontact tip	Optical fiber
Emission mode	Free running pulse	Continuous wave
Energy distribution	Gaussian	Gaussian
Pulse width	100 μs	20 μs
Energy per pulse	100 mJ	30.0 J (total energy)
Pulse repetition rate	20 pps	8 times/Selting (initiation technique)
Tip diameter	800 μm	400 μm (fiber)
Tip-to-tissue	1 mm	5 mm
Tip area	0.0050 cm^2	0.0013 cm^2
Spot diameter at tissue	0.1251 cm	0.0400 cm
Spot area at tissue	0.0123 cm^2	0.0013
Beam divergence	12.7 degrees	12.7 degrees
Water	1.5 ml/min	None
Air	None	None
Power range	2 watts	0.80–1.10 watts
Length of treatment	600 sec	240–600 sec
Speed of movement	1 mm/sec	2–10 mm/sec
Peak power	1000 watts	1.10 watts
Peak power density	81,394 w/cm	1,132 w/cm^2
Average power density	163 w/cm^2	637–875 w/cm
Total energy	1200 joules	480.0–264.0 joules
Energy density with movement	160 J/cm^2	20.0–137,4 J/cm^2