Table 5.

Table summarizing case reports of anatomical variations of roots and root canals in mandibular second premolars.

Number of roots	Root canal anatomy	Diagnostic mode	Country	Reference
1 root	3 canals	R/G	USA	Nallapati [46], 2005
	3 canals	R/G	India	N. Kararia and V. Kararia [60], 2013
	4 canals	R/G	Isreal	Holtzman [61], 1998
	4 canals	R/G	USA	Wong [62], 1991
	5 canals	R/G	Argentina	Macri and Zmener [63], 2000
	C-shaped	Micro-CT after extraction	Britain	Cleghorn et al. [55], 2008
2 roots	2 canals	R/G	India	Goswami et al. [64], 1997
	2 canals	R/G	India	Prakash et al. [65], 2008
	3 canals	R/G	China	Chan et al. [53], 1992
	3 canals	R/G	Germany	Rödig and Hülsmann [66], 2003
	3 canals	R/G	Belgium	De Moor and Calberson. [67], 2005
	3 canals	R/G	Iran	Lotfi et al. [68], 2008
	3 canals	R/G	Brazil	Soares et al. [69], 2009
	3 canals	R/G	Iran	Shokouhinejad [70], 2009
	3 canals	R/G	India	Aguiar et al. [71], 2010
	3 canals	R/G	India	Poorni et al. [49], 2010
	4 canals	R/G	USA	Bram and Fleisher [72], 1991
	4 canals	R/G	Saudi Arabia	Al-Fouzan [73], 2001
	4 canals	R/G	United Kingdom	Rhodes [74], 2001
	4 canals	R/G	Greece	Tzanetakis et al. [75], 2007
	3 canals	Extraction	USA	Fischer and Evans [54], 1992
	3 canals	R/G	Iran	Shalavi et al. [76], 2012
	3 canals	CBCT	Iran	Mokhtari et al. [77], 2013
	4 canals	Extraction	USA	Shapira and Delivanis [78], 1982
4 roots	4 canals	SCT	Indian	Sachdeva et al. [79], 2008
	4 canals	R/G	Greece	Farmakis [80], 2008

CBCT: cone beam computed tomography, Micro-CT: microcomputed tomography, SCT: spiral computed tomography, and R/G: radiograph.