Table 4 Characteristics of the included Micro- CT studies

[89]

Elnour, M., A. Khabeer, and E. AlShwaimi 2016

100

Maxillary second premolars

SkyScan 1172 X-ray scanner (Bruker Corp., Antwerp, Belgium)

27.4 μm

SkyScan CT-Volume v2.2 (Bruker Corp., Antwerp, Belgium)

Vertucci’s classification

100 s maxillary premolars were stored in 10% formalin followed by washing under water to remove the debris and then microscopic and radiographic evaluation was done.

Study revealed the following findings: one root-67%, two roots-30%, three roots-3%, one canal-30%, two canals-65%, three canals-5%, type I-17%, type II-7%, type III-9%, type and V- 23% and type VII-2%.

Detailed description of canal orifice, apical foramen and apical delta was recorded which is as follows.

One canal orifice: 55%

Two canal orifices: 45%

One apical foramen:34%

Two apical foramina:50%

Three apical foramina:11%

Four apical foramina:4%

Five apical foramina:1%

In addition to this accessory canals were found in 8% of teeth, intercanal communication was also noticed in 8% of second premolar at different locations and isthmuses were in middle (1%) and coronal third (1%).

Study concluded that Saudi subpopulation had complex root anatomy of second maxillary premolars.

[90]

El Ashiry, E.A. and N.M. Farsi 2018

100

Maxillary first molars

SkyScan micro-CT scanner (SkyScan 1172, SkyScan, Bruker, Belgium)

13.4 μm

(SkyScan 1172, SkyScan, Bruker, Belgium)

Disinfection of all the molars was done by sodium hypochlorite (5.25%), then placed in normal saline for 24 h then micro-CT was performed.

Incidence of pulpal canal orifice:

47.37% (4),

35.09% (5),

10.53% (6) and

7.01% (3).

Study concluded that increased incidence of 4 and 5 pulpal canal orifice then 3 and 6 canal orifices.

[91]

Alfouzan, K., et al. 2019

65

Maxillary first and second molars

SkyScan 1172 (Bruker microCT, Kontich, Belgium)

13.6 μm

CTAn software (Bruker microCT)

Pomeranz et al. classification

Extracted teeth were cleaned and stored in normal saline.

Among the included samples 80% of first molars had two MB canals and 17% had three. While 80% and 13% of second molar had two and three MB canals. Presence of MB2 canal at different level is as follows:

Chamber floor: 70% (1st molar), 61% (2nd molar).

1 mm depth: 15% (1st molar), 18% (2nd molar).

2 mm depth: 3% (1st molar), 18% (2nd molar).

Deeper than 2 mm: 4 (1st molar), 1 (2nd molar).

Confluent canal type was dominant then independent and fin type.

70% and 61% of MB2 canal could be easily found in 1st and 2nd maxillary molars among included Saudi population and the remaining MB2 canals were detected at deeper level.