This examination gives the insightful knowledge of smear
layer abolition proceeding and capability of conventional irrigation protocol
and continuous soft chelating irrigation protocol. Satisfactory irrigation,
disinfection, and obturation are main principle of shaping. Accumulation of
smear layer is noticed while shaping of canals which needs to abolish with the help
of irrigating solution. Whole activity needed from an irrigant to reduce smear
layer from dentin wall cannot be obtain by any sole irrigating solution.
Therefore, combined application of multiple irrigating solutions is obligatory for
optimal abolition of smear layer (5).Whereas Chloroquick solution is mix of
HEBP (a soft chelating agent) and NaOCl which can disinfect root canal as well
as reduces smear layer. Highlight of such combination of NaOCl and Etridonic
acid is that the NaOCl doesn’t surrender its biological, antibacterial and
tissue dissolving properties (13, 14), whereas the reduction and elimination of
the inorganic element is done with help of HEBP (11, 12).
Outcome of this current research demonstrate eradication
of smear layer was more decisive in middle and coronal third in comparison to
apical third. These results are in accordance with study done by Abbott PV, Heijkoop PS et al. and numerous studies, which have proved in past that
an effective cleaning action in the middle and coronal third of the root canals
even with numerous irrigation solutions, different volume, and time (15, 16).
In coronal and middle third areas where a larger canal diameter allows better
flow of solution and more time to be in contact with dentine wall which allows the
solution to remove smear layer comprehensively. (3,16).
of surfactant has been discussed and reviewed by numerous authors, incurrent
study SmearClear, SmearOFF and Chloroquick contains surfactant. Abou-Rass and
Patonai confirmed that reduction of surface tension of endodontic solutions
improved their flow into slender and narrow root canals (17). Therefore, an improved
penetration into apical narrow part of canals can be seen with addition of
surfactants to irrigation solution. In present study, SmearClear and SmearOFF
despite having additional surfactant doesn’t show the significant removal of
smear layer in apical third when compared to control group of 17% EDTA, which
does not have any addition surfactant. This result is in accordance with the
observationsof Lui et al. (18) and also, other studies have shown that calcium
chelating ability of solution is not improved by reducing the surface tension
of the solution.
study results disply that the continuous soft
chelating irrigation shows thesignificantly better removal of smear layer than
conventional irrigation protocol at apical third level when 18% HEBP was used
in combination with 5.25% NaOCl (Chloroquick High). Where 9% HEBP in
combination with 3% NaOCl (Chloroquick Low) did not show any significance
difference compared to conventional irrigation protocol groups. These resultscan
be attributed to chelating agent being more time in canal and also chelating
procedure is seen while instrumentation, unlike conventional irrigation
protocol where removal of smear layer is done only once instrumentation is
completed (19). Paque et al. demonstrated that the accumulation of hard tissue
debris in root canals when irrigated withamalgamation of NaOCl and HEBP was significantly less than irrigation
was performed with 2.5% NaOCl alone (20).Another advantage of this combination
is that it has better tissue dissolution capacity by keeping the hypochlorite-
hypochlorous acid equilibrium towards hypochlorite (21). This combination is
affective on inorganic as well as organic part of smear layer at same time.
of this study is in contrast to the recently published study by Aby
Kuruvilla et al. where 7%malic acid was
more effective in removing smear layer as compared to 17% EDTA and 18%
etidronic acid (22). This observation may be seen because 18% etidronic acid which
is soft chelating agent was merely used in a final rinse irrigation protocol.