Effect of a CO₂ Laser on the Inhibition of Root Surface Caries Adjacent to Restorations of Glass Ionomer Cement or Composite Resin: An In Vitro Study

Table 2

Microhardness analysis means (M) and standard deviations (SD) for all groups tested (similar letters indicate statistical similarity).

Groups	Depths
	20 μm		40 μm		60 μm		80 μm		100 μm		140 μm		220 μm
	M	SD	M	SD	M	SD	M	SD	M	SD	M	SD	M	SD
G1: control	17.69	4.04	18.33	3.88	21.54	4.47^b	24.42	5.43^b	24.88	5.35^c	26.06	5.85^b	28.12	7.48^b
G2: GIC	15.62	7.06	16.47	6.26	14.62	3.56^a	14.79	3.90^a	15.61	4.69^ab	14.90	4.42^a	14.34	4.23^a
G3: laser	12.83	5.62	13.28	4.11	12.71	3.07^a	12.67	4.18^a	11.90	2.56^a	12.51	3.27^a	13.44	4.24^a
G4: GIC + laser	14.15	5.22	16.00	6.86	12.21	3.43^ab	17.08	7.38^a	18.93	7.56^bc	18.40	7.01^a	17.66	8.22^a