A Comparison of Er:YAG Laser with Photon-Initiated Photoacoustic Streaming, Nd:YAG Laser, and Conventional Irrigation on the Eradication of Root Dentinal Tubule Infection by Enterococcus faecalis Biofilms: A Scanning Electron Microscopy Study

Table 2

Quantitative evaluation of biofilm reduction. Mean ± standard deviation, median, and minimum and maximum values of biofilm elimination after root canal irrigation for each group.

Group	Apical		Middle		Coronal
	Mean ± SD	Median; (min-max)	Mean ± SD	Median; (min-max)	Mean ± SD	Median; (min-max)
1		1 (1-1)		1 (1-2)		2 (1-4)
2		1 (1-2)		1 (1-3)		1 (1-3)
3		3 (2-4)		3 (1-4)		2 (1-3)
4		2 (1-3)		1 (1-3)		1 (1-2)
5		1.5 (1-2)		2 (1-2)		2 (1-3)
6		2 (1-2)		2 (1-3)		2 (1-3)
7		2 (1-3)		3 (1-4)		2 (1-4)
8		2 (2-3)		2 (1-3)		2 (1-3)
9		4 (3-4)		3.5 (3-4)		3.5 (2-4)

Groups 1 and 2: saline and 1% NaOCl with apical position of PIPS, respectively; Groups 3 and 4: saline and 1% NaOCl with coronal position of PIPS, respectively; Groups 5 and 6: Nd:YAG laser after conventional irrigation with saline and with 1% NaOCl, respectively; Groups 7 and 8: conventional irrigation with 1% NaOCl and with 6% NaOCl, respectively, negative control; and Group 9: saline solution, positive control).