Table 1: Case reports on mandibular first molar.

Reference Number of
canals
Root canal
configuration
Mesial rootDistal root

Demirbuga et al., 2013 [33]532
Ryan et al., 2011 [27]633
Kottoor et al., 2010 [41]532
Yesilsoy et al., 2009 [30]532
Chandra et al., 2009 [14]523
Barletta et al., 2008 [13]523
Fleming et al., 2010 [37]523
Alves et al., 2012 [8]633
Lee et al., 2006 [38]743
Ricucci, 1997 [12]532
Reeh, 1998 [39]633