Abst ract
Submitted: July 25, 2016
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Accepted: November 13, 2016
Effect of ult rasound st ream ing on t he
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prepared by rot ary and reciprocat ing
syst em s
1HZ WHFKQLFDO DQG VFLHQWL¿F GHYHORSPHQWV KDYH EHHQ DGYRFDWHG WR prom ot e t he success of t he endodont ic t reat m ent . I n addit ion t o rot ary and reciprocat ing syst em s, irrigat ing solut ion agit at ion has been suggest ed and passive ult rasonic irrigat ion ( PUI ) is t he m ost used. Obj ect ive: To evaluat e,
in v it r o, t he effect of ult rasound st r eam ing ( US) in t he disinfect ion of ÀDWWHQHGURRWFDQDOV\VWHPVSUHSDUHGE\WKH3UR7DSHU%LR5D&HDQG5HFLSURF syst em s, ut ilizing t he m icrobiological cult ure. Met hodology: Ext ract ed hum an m andibular incisors ( n= 84) were used. Suspensions of Ent erococcus faecalis
( ATCC 29212) were st andardized and insert ed along wit h t he t eet h im m ersed in brain- heart infusion ( BHI ) brot h. The cont am inat ion was m ade following a prot ocol during 5 days. The t eet h were random ly divided int o six groups: G1, Pr oTaper Univer sal; G2, Pr oTaper Univer sal w it h US; G3, BioRaCe; G4, BioRaCe wit h US; G5, Reciproc; and G6, Reciproc wit h US. I rrigat ion w as per f or m ed w it h salin e solu t ion . Af t er biom ech an ical pr epar at ion , m icrobiological sam ples were perform ed wit h st erilized paper point s, which were dilut ed and spread on BHI agar; aft er 48 h, t he colony form ing unit s ( CFU/ m L) were count ed for each sam ple. Result s: Groups using ult rasonic agit at ion present ed a great er ant ibact erial effect t han t he ot her ones, even using saline solut ion as irrigant . The ProTaper Universal syst em showed t he best ant ibact erial act ivit y of t he t est ed syst em s ( m edian of 0 CFU/ m L wit h and wit hout surfact ant or ult rasonic act ivat ion [ PUI ] ) . Even wit h PUI , Reciproc ( m edian of 2.5 CFU/ m L wit h PUI and 5 wit hout it ) could not reduce as m any colonies as ProTaper Universal wit hout US. The BioRaCe syst em had great er bact erial reduct ion when using US ( m edian of 0 CFU/ m L wit h PUI and 30 wit hout it ) . Conclusions: US prom ot ed great er reduct ion in t he num ber of EDFWHULDLQWKHÀDWWHQHGURRWFDQDOVSUHSDUHGZLWKQLFNHOWLWDQLXPPHFKDQL]HG syst em s. Regarding t he inst rum ent s used, t he ProTaper Universal syst em was t he m ost effect ive in reducing t he bact erial num ber.
Keyw ords: Ult rasound. Ent erococcus faecalis. I nst rum ent at ion. I rrigat ion. Layla Reginna Silva Munhoz de
VASCONCELOS1 5DTXHO=DQLQ0,'(1$1
Paloma Gagliardi MINOTTI1
Thais Cristina PEREIRA1
Marco Antonio Hungaro DUARTE1
Flaviana Bombarda de ANDRADE1
1Universidade de São Paulo, Faculdade de Odontologia de Bauru, Departamento de Dentística,
Endodontia e Materiais Odontológicos, Bauru, SP, Brasil.
I nt roduct ion
Biom echanical preparat ion plays an im port ant role
in elim inat ing bact eria and reducing t heir populat ion
in sid e t h e r oot can al sy st em . Teet h t h at h av e a
com plex anat om y can shelt er, in t he cr ev ices and
ist hm us ar eas, r em aining necr ot ic pulp t issue and EDFWHULDOELR¿OPZKLFKFDQDFWDVDSRWHQWLDOVRXUFH of per sist ent infect ions, r esult ing in t he failur e of
endodont ic t reat m ent23. I n t hese cases, Gram - posit ive
m icroorganism s are t he m ost frequent , and am ong
t hese, Ent er ococcus faecalis5 is t he m ost com m only used. This bact erial species has t he abilit y t o endure
m any ecological condit ions and it can adj ust t o let hal
challenges such as high levels of alkalinit y23, requiring
few nut rient s, adhering t o dent ine21 and penet rat ing
deeply int o t he dent inal t ubules11,14, which m akes it a
resist ant pat hogen12 and t he m icroorganism of choice
in ant im icrobial st udies in endodont ics.
1HZ WHFKQLFDO DQG VFLHQWL¿F GHYHORSPHQWV KDYH been advocat ed t o prom ot e t he success of endodont ic
t r eat m ent . I n addit ion t o r ot ar y and r ecipr ocat ing
sy st em s, i r r i g at i n g so l u t i o n ag i t at i o n h as b een
suggest ed and passive ult rasonic irrigat ion ( PUI ) is t he
m ost used29. This kind of irrigat ion has shown bet t er
result s in cleanliness and disinfect ion7. However, in
PUI , physical act ion wit hout chem ical act ion of t he
irrigant s has not been st udied.
The nick el- t it anium inst r um ent ( NiTi) Pr oTaper
Universal ( Dent sply Maillefer, Ballaigues, Swit zerland)
is m ade by m achining. The inst rum ent s of t he BioRaCe
syst em ( FKG, La Chaux- de- Fonds, Swit zerland) , also
m achined, were launched wit h elect rochem ical surface
t reat m ent , providing t he rem oval of surface defect s
t hat can init iat e a fract ure w hen t he inst rum ent is
subj ect ed t o a cyclic fat igue process13. The Reciproc
syst em ( VDW, Munich, Germ any) , which consist s of
a single NiTi inst r um ent , has gained popular it y in
clinical pract ice due t o it s reciprocat ing m ovem ent .
I t was launched wit h t he aim of reducing endodont ic
t reat m ent t im e wit hout alt ering it s effect iveness3.
Thus, t he aim of t his st udy was t o evaluat e t he
ef f ect of u lt r asou n d st r eam in g ( US) in r ed u cin g PLFURRUJDQLVPVLQWKHURRWFDQDOV\VWHPRIÀDWWHQHG t eet h prepared by t he ProTaper Universal, BioRaCe and
Reciproc syst em s, t o assess t he best clinical prot ocol t o
prom ot e great er root canal syst em decont am inat ion, VLQFH WKHVH WHHWK DUH PRUH GLI¿FXOW WR FOHDQ 7KH null hy pot hesis is t hat US does not fav or gr eat er
GLVLQIHFWLRQLQURRWFDQDOV\VWHPVRIÀDWWHQHGWHHWKDV well as t hat t he syst em s have t he sam e effect iveness.
Mat erial and m et hods
Specim en preparat ion
This st udy was approved by t he Research and Et hics
Com m it t ee of t he local universit y ( Num ber: 180/ 2011) .
Eig h t y - f ou r ex t r act ed h u m an m an d ib u lar in cisor s
were used. The t eet h had been ext ract ed for pulpal or
periodont al reasons. Radiographs in bot h direct ions ZHUH WDNHQ WR VHOHFW WHHWK ZLWK ÀDWWHQHG EXW VLQJOH canals. The select ed t eet h had a lengt h of 18 t o 22
m m and t hey were random ly dist ribut ed t o all groups.
All t eet h w er e scaled and st or ed in 1% sodium
hy pochlor it e for 4 8 h t o pr om ot e disinfect ion and
dissolut ion of or ganic t issues. Convent ional access
cavit ies were prepared using round burs and Endo- Z
bu r s ( Den t sply Maillefer, Ballaigu es, Sw it zer lan d) .
Canals were evaluat ed for apical pat ency wit h a size- 10 .¿OHDQGLQVWUXPHQWHGWRDVL]H.¿OH'HQWVSO\ Maillefer, Ballaigues, Swit zerland) 1 m m from t he root
apex and irrigat ed wit h 5 m L of saline solut ion. Then,
specim ens were subm it t ed t o t hree ult rasonic bat hs of
10 m in each one wit h 1% sodium hypochlorit e, 17%
EDTA and saline t o neut ralize t he ant erior subst ances
following t he Marinho, et al.16 ( 2014) prot ocol. Ext ernal
surfaces of all root s were sealed wit h nail polish t o allow
bact erial penet rat ion only by t he crown access and t he DSLFDOIRUDPHQSURFHGXUHFRQ¿UPHGLQDSLORWVWXG\ Aft er com plet e dr y ing of t he nail polish ( 24 h) ,
specim en s w er e in div idu ally placed in m icr ot u bes
( Axygen, Union Cit y, CA, USA) cont aining 1.5 m L of %+,EURWK%'/H3RQWGH&ODL[5zGDQR$OSHV±,VqUH France) and aut oclaved.
Specim en cont am inat ion
The bact erial reference st rain from t he Am erican
Ty pe Cult ur e Collect ion ( ATCC) num ber 2 9 2 1 2 , of
En t er ococcu s f aecalis w as ob t ain ed . Th e colon ial m orphology evaluat ion and Gram st ain were perform ed WR FRQ¿UP WKH SXULW\ RI WKH VWUDLQ DW VHYHUDO WLPHV during t he experim ent .
The m icroorganism s were cult ivat ed in BHI brot h
w it h successive subcult ur es t o achieve ex ponent ial
growt h. Dilut ions were m ade based on t he absorbance
v a l u e , o b t a i n e d b y t u r b i d i t y m e a s u r e d i n t h e
Lt da, Osasco, Brazil) unt il t he right concent rat ion was
achieved.
The t racer m icroorganism cont am inat ion was m ade
for a 5- day period at 37oC wit h asept ic and periodic
cult ure m edia changes t o m aint ain viabilit y, following
t he Ma, et al.15 ( 2011) sequence of cent rifugat ionsand
t he Andrade, et al.4 ( 2015) prot ocol, and a Scanning
(OHFWURQLF0LFURVFRSLFZDVXVHGWRFRQ¿UPWKHEDFWHULDO colonizat ion.
I nst rum ent at ion procedures
Th e st er ilized specim en s w er e div ided in t o six
groups according t o t he inst rum ent at ion syst em used
for root canal preparat ion, as follows:
G1 : Pr oTaper U ( Dent sply Maillefer, Ballaigues,
Swit zerland; n= 10) :
I n st r u m e n t a t i o n w i t h Pr o Ta p e r U w a s m a d e
using t he cr ow n- dow n t echnique accor ding t o t he
m an u fact u r er in st r u ct ion s u n t il t h e F2 in st r u m en t
was at working lengt h ( Sx, S1, S2, F1 and F2) . For
every inst rum ent change, t he irrigat ing solut ion was
renewed.
G2: ProTaper U wit h ult rasonic agit at ion ( n= 10) :
I nst rum ent at ion was perform ed in t he sam e way
as for G1; however, for every inst rum ent change, t he
irrigat ing solut ion was act ivat ed for 1 m in wit h a plain
insert in a piezoelect ric ult rasound.
G3:BioRaCe ( FKG, La Chaux- de- Fonds, Switzerland;
n= 10) :
BioRaCe syst em was used w it h t he crow n- dow n
t echnique and followed t he m anufact urer inst ruct ions
unt il t he BR3 inst rum ent was at working lengt h ( BR0,
BR1, BR2 and BR3) . For every inst rum ent change, t he
irrigat ing solut ion was renewed.
G4: BioRaCe wit h ult rasonic agit at ion ( n= 10) :
I nst rum ent at ion was perform ed in t he sam e way
as for G3; however, for every inst rum ent change, t he
irrigat ing solut ion was act ivat ed as it was for G2.
G5: Reciproc ( VDW, Munich, Germ any; n= 10) :
I n s t r u m e n t a t i o n w a s p e r f o r m e d w i t h t h e
reciprocat ing syst em using t he crown- down t echnique
and following t he m anufact urer inst ruct ions unt il t he
25/ .08 inst rum ent was at working lengt h. Before and
aft er t he inst rum ent at ion, t he irrigat ing solut ion was
renewed.
G6: Reciproc wit h ult rasonic agit at ion ( n= 10) :
I nst rum ent at ion was perform ed in t he sam e way as
for G5. Before and aft er t he use of t he inst rum ent , t he
irrigat ing solut ion was act ivat ed according t o groups
2 and 4.
Two st erilized t eet h per group were not subm it t ed t o cont am inat ion prot ocol and were considered negat ive
cont rol. As posit ive cont rol, t wo t eet h per group were subm it t ed t o cont am inat ion pr ot ocol but w er e not
inst rum ent ed, proving t he st andardizat ion of t he init ial
cont am inat ion4.
Th e sam e op er at or p er f or m ed all p r oced u r es.
Every root canal was irrigat ed wit h a t ot al of 10 m L
of st erilized saline solut ion bet ween each inst rum ent
wit h a NaviTip needle of 21 m m and 30 ga of diam et er
( Ult radent , Sout h Jordan, USA) posit ioned at 3 m m
short of t he working lengt h. I n groups 2, 4 and 6, t he
irrigant was dispensed before ult rasonic agit at ion. For
t he ult rasonic agit at ion, an ult rasonic device act ivat ed
by a piezoelect ric ceram ic pellet syst em at a frequency
of 30,000 Hz ( Jet Sonic, Gnat us, São Paulo, Brazil) by
a plain insert ( TU13, Trinit Periodont ology, São Paulo,
Brazil) for 1 m in was used, in all ult rasonic groups;
t he procedure was conduct ed wit h vert ical m ovem ent s
in t he buccal- lingual and m esial- dist al direct ions ( 30
seconds for each dir ect ion) in “ endo m ode” ( 50%
p ot en cy ) . All ex p er im en t s w er e p er f or m ed u n d er DVHSWLFFRQGLWLRQVLQDODPLQDUÀRZFKDPEHUWRSUHYHQW airborne bact erial cont am inat ion.
Sam ple collect ion
Teet h cr ow n s w er e decon t am in at ed by a sw ab
soaked in 5.25% sodium hypochlorit e for 30 seconds
and neut ralized wit h 5% sodium t hiosulfat e. Bact erial
sam ples were collect ed by t wo absorbent # 20 paper
cones ( Dent sply Maillefer, Ballaigues, Sw it zer land)
from t he root canal, t aking 1 m in for each cone, and
t h en t r an sf er r ed t o m icr ot u bes w it h 1 m L of BHI
br ot h. Micr ot ubes w er e agit at ed in a vor t ex for 10
seconds and 100 m L of t he cont ent of each t ube was
t ransferred t o ot her m icrot ubes, unt il it reached t he
10- 4 concent rat ion. Aliquot s of 100 m L of t he dilut ions
were seeded in Pet ri dishes wit h BHI - agar brot h. The
dishes were st ored in a bact eriological incubat or for
48 h before t he count ing of t he CFU/ m L.
Dat a were collect ed, insert ed in a spreadsheet and
st at ist ically analyzed using t he SPSS 15.0 soft ware.
To co m p a r e t h e CFU/ m L b e t w e e n t h e d i f f e r e n t
in st r u m en t at ion sy st em s, t h e Kr u sk al- Wallis t est
Result s
Al l i n s t r u m e n t e d t e e t h s h o w e d a b a c t e r i a l
reduct ion in t he root canal when com pared wit h t he
posit ive cont rol ( m edian of t he cont rol = 100 CFU/
m L) . The groups using ult rasound agit at ion showed D VLJQL¿FDQWO\ JUHDWHU UHGXFWLRQ RI PLFURRUJDQLVPV when com pared wit h t he groups wit hout ult rasound
agit at ion, except t he ProTaper group t hat showed t he
sam e result s wit h and wit hout t he ult rasound agit at ion
( m edian = 0 CFU/ m L) . BioRaCe groups present ed a
m edian of 0.0 CFU/ m L wit h PUI , and a m edian of 30.0
CFU/ m L wit hout PUI . Reciproc groups had a m edian
of 2.5 CFU/ m L wit h PUI and a m edian of 5.0 CFU/ m L
wit hout PUI .
Regarding t he t est ed syst em s, ProTaper U showed DVWDWLVWLFDOVLJQL¿FDQWGLIIHUHQFHZKHQFRPSDUHGZLWK BioRaCe and Recipr oc gr oups w it hout ult rasound,
and also, when com pared wit h t he posit ive cont rol
(p7KHUHZDVDVWDWLVWLFDOVLJQL¿FDQWGLIIHUHQFH
bet ween BioRaCe inst rum ent at ion wit h and wit hout
ult rasonic use (p< 0.05) . When BioRaCe and Reciproc gr oups w er e com par ed w it h each ot her, t her e was QRW VWDWLVWLFDO VLJQL¿FDQW GLIIHUHQFH p< 0.05) . Also,
WKHUHZDVQRWVWDWLVWLFDOVLJQL¿FDQWGLIIHUHQFHEHWZHHQ BioRaCe an d Recipr oc gr ou ps w it h ou t u lt r asou n d
and t he posit iv e cont r ol (p< 0. 05) . Ther e w as not VWDWLVWLFDOVLJQL¿FDQWGLIIHUHQFHEHWZHHQWKH5HFLSURF inst rum ent at ion wit h and wit hout ult rasonic agit at ion
( Table 1) .
I n t he group of BioRaCe syst em wit hout ult rasonic
agit at ion t here was one specim en wit hout bact erial
growt h, while when t he ult rasound was used wit h t he
sam e syst em 7 specim ens did not present bact erial
growt h. I n ProTaper U group, 7 specim ens did not
present bact erial growt h, but when t he ult rasound was
used t his num ber raised t o 9. The Reciproc syst em
group present ed 2 specim ens wit hout bact erial growt h
w it hout ult rasound agit at ion and 3 specim ens w it h
no bact erial growt h when t he ult rasound was used.
No specim ens of negat ive cont rol present ed bact erial
growt h. Only 3 specim ens of t he BioRaCe syst em group
wit hout ult rasonic agit at ion present ed m ore t han 100
CFU/ m L, as well as all t he specim ens from t he posit ive
cont rol ( Figure 1) .
Discussion
This st udy evaluat ed t he effect of t he ult rasound
st ream ing in t he disinfect ion of root canals. The null
hypot hesis t est ed was rej ect ed since t he ult rasound
agit at ion f av or ed a gr eat er disin f ect ion af t er t h e LQVWUXPHQWDWLRQZLWKURWDU\V\VWHPLQÀDWWHQHGURRW canals and t he syst em s had different ant im icrobial
effect iveness.
Si m i l a r t o t h e Ma , e t a l .1 5 ( 2 0 1 1 ) i n v i t r o st u d y, ce n t r i f u g a t i o n s w e r e p e r f o r m e d d u r i n g WKH FRQWDPLQDWLRQ RI WKH WHHWK WR ¿OO WKH GHQWLQDO t ubules wit h E. faecalis.However, in t his st udy, m ore
Groups Teeth without bacterial
growth
BioRaCe 1
BioRaCe + Ultrasound 7
ProTaper U 7
ProTaper U + Ultrasound 9
Reciproc 2
Reciproc + Ultrasound 3 Positive control 0 Negative control 10
Figure 1- Number of teeth without bacterial growth for each group
Groups Without Ultrasound With Ultrasound
BioRaCe 30.0
(3.0-122.0)b,c
0.0 (0.0-3.0)a
ProTaper 0.0
(0.0-23.0)a
0.0 (0.0-3.0)a
Reciproc 5.0
(0.0-64.0)a,b,c
2.5 (0.0-27.0)a,b
Positive control 100.0 (100.0-100.0)c
100.0 (100.0-100.0)c
Negative control 0.0 (0.0-0.0)a
0.0 (0.0-0.0)a
Table 1- Median, minimum and maximum CFU/mL after the biomechanical preparation of each group, with and without ultrasound.
'LIIHUHQWORZHUFDVHOHWWHUVLQGLFDWHGLIIHUHQWVWDWLVWLFDOVLJQL¿FDQFHV
cent rifugat ions were m ade, based on t he Andrade, et
al.4 ( 2015) prot ocol, as t he ent ire t oot h was used, not
only a dent in block. Root s of all t eet h were sealed wit h
nail polish t o ensure t hat t he cont am inat ion penet rat ed
only t hrough t he access cavit ies.
$QHI¿FLHQWFKHPLFDODQGPHFKDQLFDOSUHSDUDWLRQ is essent ial t o decont am inat ion of t he r oot canal,
elim inat ing bact eria and t heir byproduct s, pulp and
cont am inat ed dent in6. Shaping and ir r igat ion w it h
ant im icrobial solut ions are able t o reduce or elim inat e
t he num ber of bact er ia inside t he r oot canals26, 27.
How ev er, anat om ical com plex it ies can r educe t he
cleaning effect s of t he inst rum ent at ion and irrigat ion2.
St udies have shown t hat approxim at ely one- t hird of t he
canal walls are not t ouched by t he inst rum ent s19 and
t hat even t he t ouched walls are not free of bact eria17.
Shaping by hand or wit h NiTi rot ary inst rum ent s has DOLPLWHGHIIHFWLYHQHVVLQÀDWFDQDOVLQZKLFKWR 40% of t he root canal walls are not t ouched19. The NiTi
r ot ar y inst r um ent s pr om ot e a cir cular pr eparat ion,
leaving t he buccal and lingual ext ensions wit h debris25.
Thus, m andibular hum an incisors were chosen for t his VWXG\GXHWRWKHLUÀDWWHQHGFRQIRUPDWLRQ
I n t his st udy t here were a great num ber of canals
wit h negat ive cult ures. The probable reason for t his is
t hat t he sam ple collect ion was m ade only in t he m ain
root canal wit h absorbent paper point s, so, bact eria
m ay st ill rem ain inside dent ine deep t ubules.
PUI is m ore effect ive t han convent ional irrigat ion
in clean in g t h e r oot can al sy st em2 5 , 2 9. Th is k in d
of ir r ig at ion h as t h e p ot en t ial t o r em ov e d en t in
debr is and or ganic t issue fr om ar eas inaccessible
t o inst rum ent at ion29 5|GLJ HW DO24 ( 2010) showed
t hat PUI was m or e effect ive t han ir r igat ion w it h a
syringe and a sonic syst em in t he rem oval of debris
in canal ir r egular it ies, w it h a com plet e r em oval of
debr is in 92.5% of sam ples. When pulp r em nant s
and debris accum ulat ion are present , bact eria com e
t o h ar bor t h ese m at er ials. Becau se of t h at , it is
rat ional t o suppose t hat elim inat ion of debr is can
collaborat e t o m icroorganism elim inat ion. I n t his st udy,
approxim at ely 99% of t he bact eria were elim inat ed in
t he groups wit h ult rasonic agit at ion.
Most of t he st udies t hat have invest igat ed t he
an t im icr ob ial ef f ect iv en ess of PUI h av e u sed an
ant im icrobial solut ion as an irrigant2,24. I n our st udy,
saline was used t o observe only t he physical effect of
PUI and t he abilit y of different m echanical inst rum ent s
t o prom ot e disinfect ion. Even wit hout an ant im icrobial
solu t ion , t h e in st r u m en t at ion w as able t o r edu ce
t he num ber of bact eria in t he root canal. When t he
preparat ion was associat ed wit h t he ult rasound, result s
showed elim inat ion of alm ost all bact eria, even wit h
t he innocuous irrigant . Carver, et al.8 ( 2007) show ed
t hat t he addit ion of ult rasound prom ot ed a sevenfold
reduct ion in CFU/ m L. Aft er t he root canal preparat ion,
PUI allows t he insert t o freely swing inside t he canal,
t hus causing cavit at ion and t he physical disrupt ion RI WKH EDFWHULDO ELR¿OP1 , 2 0. I n t h is st u dy, t h e PUI was used aft er each inst rum ent due t o t he fact t hat
inst r um ent at ion pr oduces debr is and sm ear lay er,
which, clinically, can be a prot ocol.
The rot ary syst em s ProTaper U and BioRaCe and
t he reciprocat ing syst em Reciproc were chosen due t o
t heir different m anufact uring m et hods, sect ions and
prot ocols of use3,9ZKLFKFDQLQÀXHQFHWKHDELOLW\WR
decont am inat e t he root canal.
The ProTaper U syst em showed t he sm aller m edian
of CFU/ m L w hen com par ed w it h t he BioRaCe and
Reciproc syst em s. The ProTaper U, when cont rast ed t o
ot her NiTi rot ary syst em s, prom ot ed a m ore aggressive
dent in cut , which led t o a great er bact erial reduct ion10
in agreem ent t o ot her st udies9,18. Besides prom ot ing
g r ea t er d en t i n r em o v a l , t h i s sy st em h a s m o r e
inst rum ent s t han t he ot hers t est ed, which leads t o a
great er am ount of irrigat ing solut ion and ult rasound
used during t he preparat ion.
All t he syst em s have t he sam e 0.25 m m apical GLDPHWHUEXWWKHLUWDSHUVYDU\ZKLFKFDQLQÀXHQFH result s. I n t he ProTaper U syst em , t he F2 inst rum ent
has a t aper of 0.8, t he sam e as t he Reciproc syst em ’s ¿OH,QWKH%LR5D&HV\VWHPKRZHYHUWKH%5 ¿OH KDV D WDSHU RI 7KXV WKH %LR5D&H V\VWHP w ore away a sm aller dent in area, result ing in less
decon t am in at ion . I n addit ion , w h en Recipr oc w as
com pared wit h ProTaper U, t he lat t er showed a great er
r em oval of dent in7, w hich can ex plain t he r esult s.
2QWKHRWKHUKDQGWKHQXPEHURI¿OHVXVHGLQHDFK group is different : 5 in t he ProTaper U group, 4 in t he
BioRaCe group and 1 in t he Reciproc group, and by WKHIDFWWKDWWKHXOWUDVRXQGZDVXVHGDIWHUHDFK¿OH t his leads t o different overall t im e regarding it s use
Conclusion
US prom ot ed great er reduct ion in t he num ber of EDFWHULD LQ WKH ÀDWWHQHG URRW FDQDOV SUHSDUHG ZLWK nickel- t it anium m echanized syst em s. Regarding t he
inst rum ent s used, t he ProTaper Universal syst em was
t he m ost effect ive in reducing t he bact erial num ber.
Acknowledgm ent s
7KLVVWXG\ZDVVXSSRUWHGE\)$3(63±6mR3DXOR Research Foundat ion ( Proc. no. 2 2010/ 20186- 3 and
2011/ 18479- 5) .
References
1- Ahm ad M, Pit t Ford TR, Crum LA. Ult rasonic debridem ent of root
canals: an insight int o t he m echanism s involved. J Endod. 1987; 13:
93- 101.
2- Alves FRF, Alm eida BM, Neves MAS, Moreno JO, Rôças I N, Siqueira
Jr. Disinfect ing oval- shaped r oot canals: effect iveness of differ ent
supplem ent ary approaches. J Endod. 2011; 37: 496- 501.
3- Am aral P, Forner L, Llena C. Sm ear layer rem oval in canals shaped
wit h reciprocat ing rot ary syst em s. J Clin Exp Dent . 2013; 5e227- 30.
4- Andrade FB, Arias MP, Maliza AG, Duart e MA, Graeff MS, Am
oroso-Silva PA, et al. A new im pr oved pr ot ocol for in v it r o int rat ubular
dent inal bact erial cont am inat ion for ant im icrobial endodont ic t est s:
st andardizat ion and validat ion by confocal laser scanning m icroscopy.
J Appl Oral Sci. 2015; 23: 591- 8.
$QWXQHV+65{oDV,1$OYHV)56LTXHLUD-)-U7RWDODQGVSHFL¿F
bact erial levels in t he apical root canal syst em of t eet h wit h post
-t rea-t m en-t apical periodon-t i-t is. J Endod. 2015; 41( 7) : 1037- 42.
6- Barat t o F Filho, Leonardi DP, Zielak JC, Vanni JR, Sayão- Maia SM,
6RXVD 0' 1HWR ,QÀXHQFH RI 3UR7DSHU ¿QLVKLQJ ¿OHV DQG VRGLXP
hypochlorit e on cleaning and shaping of m andibular cent ral incisors - a
hist ological analysis. J Appl Oral Sci. 2009; 17: 229- 33.
%UNOHLQ6+LQVFKLW]D.'DPPDVFKNH76FKlIHU(6KDSLQJDELOLW\ DQGFOHDQLQJHIIHFWLYHQHVVRIWZRVLQJOH¿OHV\VWHPVLQVHYHUHO\FXUYHG
root canalsof ext ract ed t eet h: reciproc and WaveOne versus Mt wo and
ProTaper. I nt Endod J. 2012; 45: 449- 61.
8- Car v er K, Nusst ein J, Reader A, Beck M. I n v iv o ant ibact er ial
HI¿FDF\RIXOWUDVRXQGDIWHUKDQGDQGURWDU\LQVWUXPHQWDWLRQLQKXPDQ
m andibular m olars. J Endod 2007; 33: 1038- 43.
)D\\DG'0(OKDNLP(OJHQG\$$&XWWLQJHI¿FLHQF\RIWZLVWHGYHUVXV PDFKLQHGQLFNHOWLWDQLXPHQGRGRQWLF¿OHV-(QGRG
10- Gorduysus M, Nagas E, Torun OU. A com parison of t hree rot ary
syst em s and hand inst rum ent at ion t echnique for t he elim inat ion of
Ent erococcus faecalis from t he root canal. Aust Endod J. 2010; 37:
128-33.
11- Haapasalo M, Orst avik D. I n vit r o infect ion and disinfect ion of
dent inal t ubules. J Dent Res. 1987; 66: 1375- 9.
12- Hubble TS, Hat t on JF, Nallapar eddy SR, Mur ray BE, Gillespie
0- ,QÀXHQFH RIEnt er ococcus faecalis prot eases and t he collagen-binding prot ein, Ace, on adhesion t o dent in. Oral Microbiol I m m unol.
2003; 18: 121- 6.
13- Lopes HP, Elias CN, Vieira VT, Moreira EJ, Marques RV, Oliveira
JC, et al. Effect s of elect ropolishing surface t reat m ent on t he cyclic
fat igue resist ance of BioRaCe nickel- t it anium rot ary inst rum ent s. J
Endod. 2010; 36: 1653- 7.
14- Love RM. Ent er ococcus faecalis ± D PHFKDQLVP IRU LWV UROH LQ endodont ic failure I nt Endod J. 2001; 34( 5) 399- 405.
15- Ma J, Wang Z, Shen Y, Haapasalo M. A new noninvasive m odel t o
st udy t he effect iveness of dent in disinfect ion by using confocal laser
scanning m icroscopy. J Endod. 2011; 37: 1380- 5.
16- Marinho AC, Mart inho FC, Gonçalves LM, Rabang HR, Gom es BP.
'RHVWKHUHFLSURF¿OHUHPRYHURRWFDQDOEDFWHULDDQGHQGRWR[LQVDV HIIHFWLYHO\DVPXOWL¿OHURWDU\V\VWHPV"
1 7 - Paqu é F, Balm er M, At t in T, Pet er s AO. Pr epar at ion of
oval-sh ap ed r oot can als in m an d ib u lar m olar s u sin g n ick el- t it an iu m
rot ary inst rum ent s: a m icro- com put ed t om ography st udy. J Endod.
2010; 36: 703- 7.
1 8 - Paq u é F, Mu sch U, Hu lsm an n M. Com p ar ison of r oot can al
preparat ion using RaCe and ProTaper rot ary Ni-Ti inst rum ent s. I nt
Endod J. 2006; 38: 8- 16.
19- Pet ers AO. Current challenges and concept s in t he preparat ion of
root canal syst em s: a review. J Endod. 2004; 30: 559- 67.
20- Plot ino G, Pam eij er CH, Grande NM, Som m a F Ult rasonics in
HQGRGRQWLFVDUHYLHZRIWKHOLWHUDWXUH-(QGRG±
21- Port enier I , Walt im o TM, Haapasalo M. Ent er ococcus faecalis±WKH root canal survivor and ‘st ar ’in post - t reat m ent disease. Endod. t opics.
2003; 6: 135- 59.
22- Ran S, Liu B, Jiang W, Sun Z, Liang J. Transcript om e analysis of
Ent er ococcus faecalis in response t o alkaline st ress. Front Microbiol.
2015; 6: 795.
2 3 - Ricu cci D, Siq u eir a JF Jr, Bat e AL, Pit t For d TR. Hist olog ic
invest igat ion of root canal- t reat ed t eet h wit h apical periodont it is: a
ret rospect ive st udy from t went y- four pat ient s. J Endod. 2009; 35:
493-502.
5|GLJ7%R]NXUW0.RQLHWVFKNH)+OVPDQQ0&RPSDULVRQRI
t he Vibringe syst em wit h syringe and passive ult rasonic irrigat ion in
r em oving debr is fr om sim ulat ed r oot canal ir r egular it ies. J Endod.
2010; 36: 1410- 3.
5|GLJ7+OVPDQQ00XKJH06FKlIHUV)4XDOLW\RISUHSDUDWLRQ
of oval dist al root canals in m andibular m olars using nickel- t it anium
inst rum ent s. I nt Endod J. 2002; 35: 919- 28.
26- Shuping GB, Ørst avik D, Sigurdsson A, Trope M. Reduct ion of
int racanal bact eria using nickel t it anium rot ary inst rum ent at ion and
various m edicat ions. J Endod. 2000; 26: 751- 5.
27- Siqueira JF Jr, Rocas I N, Sant os SR, Lim a KC, Magalhaes FA,
GH 8]HGD 0 (I¿FDF\ RI LQVWUXPHQWDWLRQ WHFKQLTXHV DQG LUULJDWLRQ
regim ens in reducing t he bact erial populat ion wit hin root canals. J
Endod. 2002; 28: 181- 4.
28- Siqueira JF Jr, Rôças I N. Polym erase chain react ion- based analysis
of m icroorganism s associat ed wit h failed endodont ic t rat am ent . Oral
Surg Oral Med Oral Pat hol Oral Radiol Endod. 2004; 97: 85- 94.
29- Van der Sluis LW, Ver sluis M, Wu MK, Wesselink PR. Passive
ult rasonic irrigat ion of t he root canal: a review of t he lit erat ure. I nt
