Table 2. List of the excluded articles and reasons that led to their exclusion.

No.	First author	Year	Nonrandomized groups	Not standardized techniques	Less than 6 months of follow-up	Less than 200 third molars removed	Others
1	Mavrodi	2015	X	X
2	Osunde	2014	X	X
3	Yadav	2014	X
4	Kale	2014				X
5	Nguyen	2014		X
6	Charan Babu	2013	X		X	X
7	Smith	2013	X
8	Guerrouani	2013		X
9	Janakiraman	2010				X
10	Cheung	2010	X	X
11	Baqain	2010	X
12	Akadiri	2009				X
13	Gomes	2005				X
14	Robert	2005					Insufficient data
15	Chossegros	2002					Only germectomy
16	Hägler	2002					Insufficient data
17	Renton	2001	X	X
18	Bataineh	2001	X
19	Gülicher	2001		X
20	Ramadas	2001		X
21	Pichler	2001					Study design not pertinent
22	Valmaseda-Castellón	2000	X
23	Gülicher	2000		X
24	Moss	1999		X
25	Brann	1999		X
26	Black	1997			X
27	Greenwood	1994			X
28	To	1994		X
29	Schultze-Mosgau	1993		X
30	Rood	1992	X	X
31	Carmichael	1992	X	X
32	Obiechina	1990		X