AP CHl Y DdOC U M SANG 108 ^ Tap 11-564/2016
Vhan xet dac digm vi khuan trong benh ly tuy rang hoai t u
[Characteristic evaluation of bacteria in teeth with pulp necrosis
'Nguyen Th^ Hanh, Pham Th} Thu Hi^n, D6 Thu Trang Benh vien Rdng Hdm Mat TWHa Noi
Tom t a t
Muc tiiu: Xac djnh sd lupng va sU cd mat cCia mdt sd loai vi khuan trong dng tCiy rang hoai t d . Doi tugng vd phuang phdp: ChUng tdi tien h l n h k h i m , chan d o l n va l l y m l u xet nghiem d 41 rang vTnh v i l n dupc chan doan tOy hoai t d tai B i n h v i l n Rang Ham Mat Trung uong Ha Ndi, thdi gian t d 11 /2011 den 08/2015. Thuc hien l l y mau bgnh pham trong dng tOy, tien hanh nudi c l y ky khiva glal trinh t u gen tim vl khuan. PhUtfng phap nghien cdu m d t l eat ngang. Kit qud vd kit ludn: AM4\ rang cd ket q u i dUtfng tfnh vdi vi khuan. Sd lupng vi khuIn trung binh trong dng tOy > 4,11 x 10^CFU/ml (dao ddng t d 1,18 x 10^
CFU/ml d e n > 7 x 10^CFU/ml). M d t s d loai xuat hien nhieu nhat d t r o n g dng tuy la Veillonella sp 0'ifi%), S.oralis, M.micros (57,1%). Mot sd loai cd sd lUpng vi khuan trung binh tr&n mau dUOng tinh cao nhat I I S.mitis (>1,25 X 10=CFU/ml), P. oralis{> 1 x 10^CFU/ml).
TUkhda: Vi khuan, tuy rang hoai t d .
Objective: To determine the number and the presence of some bacteria in the canals of teeth with pulp necrosis. Subject and method: The study included 41 teeth which were diagnosed as pulp necrosis at the Hanoi National Hospital of Odonto-Stomatology, from November 2011 t o August 2015. Samples were taken, anaerobic culture was conducted and DNA sequencing was implemented t o find bacteria.
Methods: Cross-sectional descriptive study. Result and conclusion: 41/41 teeth were positive with bacteria. The average number of bacteria in the root canal is more than 4.11 x 10^CFU/ml (rangedsfrom 1.18 x lO^CFU/ml t o more than 7 x lO^CFU/ml). Species appeared most frequently In t h e canal were Veilloneila sp (71.4%), S.oralis, M.mieros (57.1%). Species had the highest average number of bacteria in the positive samples were S.mitis (> 1.25 x 10'CFU/ml), P. oralis (> 1 x 1 O^CFU/ml).
Keywords: Bacteria, teeth with pulp necrosis.
'han bien khoa hgc. PGS.TS. TA ANH TUAN
lOURNAL OF 108 - CLINICAL MEDICINE AND PHARMACY Vol.11-N°4/2016
1. Oat vin de
Nen ting cua dllu trj ndi nha nhdng rang tCiy fioai td m l nguyen nhan do vl khuan phu thudc vio /\ec xac dinh va loai bd ehung de dat dupe sU linh thuong tdi Uu. Vai trd cDa vi khuan va nhOmg sin pham cua chUng tao ra trong binh can cua binh tCiy rang hoai td va viem quanh cudng ring da ddpc nhleu tie gia nghien cdu [1], [10]. Bystrdm va Sundqvist [3], nhan thay tat ca cle rang tuy hoai td vh vilm quanh cudng man ddpc x i t nghiem, hlu het dlu cd vi khuan. Cle tie gia nhd Fabris v l CS [4], Peeiuliene va CS [8], w... khi tien hanh nghien cdu ve sd lupng, ehCing loai vi khuan trong dng tuy va viing quanh chdp rang, dlu cho rang md tdy hoai td ed rat nhieu loai vi khuan, chd yeu la cac vi khuan ky kht. Tuy nhien, cd rat it cac nghien cdu chi ra cu t h i v l ehung loai vi khuan trong dng tCiy va sd Idpng cCia mdi loli. Do vay, chOng tdi tien hlnh nghien cdu de tai nay nhIm xac ^ n h sd lupng va su cd mat cCia mdt sd loai vl khuan trong dng tuy rang hoai td.
2. Ddi turafng va phUtfng phip
41 ring vinh vien dupc chan doln tijy hoai td, khdng ed 15 dd v l ehua dupc dieu tri td trude. ChOng tdi tien hanh each ly ring tdn thUdng vdi mdi trUdng mieng bang dam cao su, md tCiy v l bde Id mieng dng tOy. Sd dung edn gily vd trung dua vao budng tOy va dng tCiy de lay mau xet nghiem. Cae mlu xet nghiem dupe tiln hanh nudi cay ky khi va dem sd lupng vl khuan mpc. Trong tdng sd 41 rang nghien edu, ehung tdi tien hanh tieh ehiet DNA, chay PCR va giai trinh tu gen d 14 rang dexac dinh chCing loai vi khuan va dem sd lupng cua tdng loll. Sd lupng vi khuan dupc tinh theo don v| CFU/ml. Cac xet nghiem dupe thue hien tai Khoa Xit nghiem, Benh vien Benh nhiet ddi Trung uong.
3. Ket qud
Qua nghien cdu chung tdi thu dupc k i t qua nhusau:
3.1. Sued mat vd solugng vi khu6n drdng tdy hoai td
Being 1. SU CO mat va s6 lUorng vi khuan d rang tdy hoai ti!r
K^t q u i Mau duong t i n h vdi vi khuan
Sd lupng vi khuan trung binh K h o i n g dao ddng
Sd liTOng
41/41
> 4 , n x 1 0 S C F U / m l 1,18x105CFU/mlden
>7x10SCFU/ml
Ket qua d bing tren cho thiy, sd mlu duang tinh vdi vi khuan la 41/41, chiem t^ le 100%.
Sd lupng vl khuIn trung binh trong dng tOy la >
4,11 x 1 O^CFU/ml. Sd lupng vl khuIn trong dng tuy thap nhat la 1,18x10^FU/ml, eao nhat la >7x1tf CFU/ml
3.2. So luong vd svt c6 mat cda mot solodi vi khu6n drdng tdy hoai tuf
Trong tdng sd 41 rang nghien edu, ehung tdi tien hlnh tach chiet DNA, chay PCR va gili trinh tU gen d 14 rang de xac djnh chung loai vi khuan va dem sd lupng cCia ti^ng loll. Ket qua dupe the hien d bang sau
BSng 2. Sd lifc^g va sd c6 mat cua mdt s6 ioSi vl khuan d rang tCiy hoai tiir
L,oai vi khuan
S. dnginosus S. oralis S. mitis S. sanguinis M. micros Veilloneila sp V. parvula E. faecatis P. oralis L salivarlus
So mau coVK
3/14 8/14 4/14 6/14 8/14 5/14 4/14 3/14 5/14 1/14
Ti\i
%
21,4 57,1 28,6 42,9 57,1 42,9 28,6 21,4 42,9 7,1
Soluong VK/maucoVK
(CFU/ml)
> 7,8x10*
> 8,94x10*
> l , 2 5 x l 0 '
> 8 , 2 5 x 1 0 '
> 9,75x10*
> 9 , 1 7 x l 0 *
> 8,75x10''
> 4 , 3 x 1 0 *
> l x l 0 5
> 4 x l O *
Nhdn xet: Loai vi Ichuan xuat liien vdi t^ le cao
nhat trong ngiiien ciJu cua chung toi la Veilloneila sp
(10/14 rang, chiem t) le 71,4 %), trong do, chdng toi
TAP CHI Y DL/OC L A M SANG 108 rap 11-564/2016
p h i n l i p d u p c l o l i V. pan/ula cd mat d 4 / 1 4 rang, chiem t ^ le 28,6%. M o t sd l o l i x u l t hien vdi t ^ le kha cao la 5. oralis v l M. micros, chiem t y le 57,1%. Loai xuat hien it nhat la L. salivarlus chdng t d i chi gap mdt t r d d n g hpp, chiem t ^ i l 7,1 %.
M d t sd loai ed sd l u p n g t r u n g binh t r l n m a u cd m i t vi khuan eao nhat I I S. mitis (> 1,25 x 10=CFU/ml), P. oralis (> 1 x Itf'CFU/ml). Loai cd sd Idpng t r u n g binh tren m l u cd vi khuan t h i p n h i t la L salivarlus (> 4 x 1 O^CFU/ml).
4.1, SU CO mat vd sd iuang vi khudn d rang tdy hogitvf
4.1.1. Sued mat cda vi khudn
Ket q u i nghien cdu cOa chung tdi thay, 41/41 rang cd mat cOa vl khuan, chiem t ^ 11100%. D i l u n l y cho thay, cd mdi Hen quan gida b i n h I)? tuy hoai t d vdi sdxuat hien eda vi k h u l n .
M d t sd tae gia khi n g h i l n edu sU eo mat cCia vi k h u l n t r o n g benh ly tCiy rang hoai t d v a viem q u a n h cudng cijng cho ket q u i t u o n g tU. Nghien cdu cCia Peters va CS [10] d 43 rang thay, 100% sd rang cd mat vi khuan. Shuping va CS [11], thay 98% t r o n g t d n g sd 42 rang n g h i l n cdu cd s d xuat h i l n cda vi k h u l n . N g h i l n cdu d 60 rang cCia Yared va CS [16]
t h i y , 100% sd r i n g cd mat vl khuan. Orstvik va CS [6]
n h l n thay, sd r i n g cd sd xuat h i l n eua vi khuan chiem 96%.
4.1.2. So lugng vi khudn drdng tClyhogi tU Nghien cdu cOa chung t d i thay r i n g , sd lupng vi khuan t r u n g binh t r o n g mau xet n g h i i m la kha Idn >
4,11 X1 O^CFU/ml (dao d d n g t d 1,18 x 10^CFU/ml den
> 7 x 1 0 X F U / m l ) . -
Ket qua eda ehung t d i p h d hpp vdi n g h i l n cdu e C i a c l c t a c g i a n h U :
Nghien cdu d 20 rang m d t chan cDa Bystrdm va CS [1] eho ket q u i , sd lUpng vi khuan t r u n g binh la 3 X lO'CFU/ml (dao d d n g t d 6 x 10^ den 2 x 10^
CFU/ml). Ket q u i n g h i l n cdu eua Siqueira va CS [12]
d 11 rang eda t h i y , sd lupng vi Idiuan dao d d n g t d 4 X 1 0 ' d e n 2 X lO^CFU/ml. Sjogren va CS [13], nghien
cdu d 18 rang t d y hoai t d cho k i t q u i , sd lUpng v i khuan la 9,8 x lO'CFU/ml (dao d d n g t d < 10^ d e n 6,4 X 10* CFU/ml). M d t n g h i l n c d u khac d 43 rang tCiy hoai t d va v i e m q u a n h c u d n g cda Peters va CS [10]
cho thay, s d j u p n g ' y i khuan t r u n g b i n h la 7,6 x 1 0 ' CFU/ml (dao d p n g ' t i ^ 8 x 10^ d i n 3 x 10'CFU/ml).
Bystrom va CS [3],'tien h l n h n g h i e n cdu d 30 rang 1 chan t h ^ y , s6 Idpng vi khuan dao d d n g t d 2,4 x 10*
CFU/ml den 1,5 x 10«CFU/ml.
B i e u d o cho thay, v i khuan t h u d n g x u y i n h i e n dien t r o n g d n g t u y rang hoai t d v d l sd l u p n g kha I d n . 4.2. So lifong vd sU cd mat cda mot so lodi vi khudn drdng tdy hoai tdf
Qua ket qua g i l l t r i n h tU gen d 14 rang, ehdng t d i b i n luan v l sd lUpng va sU ed mat cda m o t sd loai vi khuan sau.
4.2.1. Veilloneila sp
L I vi khuan ed t i n suat x u l t h i l n nhieu nhat t r o n g nghien c d u cua chung t d i . c h d n g t d i t h i y Veilloneila sp cd m a t d 10/14 rang, chiem t y le 71,4%.
T r o n g d o , chUng t d i p h i n lap dupe l o l l V. parvulla xuat hien d 4 t r u d n g h p p . Sd lupng eCia vi k h u l n n l y eung chiem k h i Idn so vdi cac l o l i vi khuan k h i c , sd lupng vi k h u l n t r u n g b i n h tren m a u cd mat vl khuan nay la > 9 x 10*CFU/ml. Dieu d o cho thay, Veilloneila sp ta vi khuan gap tucfng ddi p h d b i l n t r o n g t d y r i n g hoai t d .
Veilloneila sp la cac eau khuan Gram (-), ky khi, chCing thupc t h a n h phan he vi khuan b i n h t h u d n g d mierig va d d d n g tieu hda. Chi Veilloneila sp d d p c chia t h a n h rat nhleu loai, t r o n g d d Ioai V. parvula ed kha nang g l y viem xUdng tOy va viem npi t i m mac.
Say la vi khuan gap t ^ le r i t cao t r o n g n g h i e n edu cua chung t d i , n h u n g cac tai lieu n g h i l n c d u vl khuan hpc t r o n g b i n h ly t u y rang t r u d c day, cd rat ft tai lieu de e l p den vi khuan nay. M d t sd t i e g i l m d i ehi dua ra t y le vi khuan t r o n g d n g ti!iy rang t h u d e n h d i n e l u khuan Gram (-) h o l e t ^ I I x u a t hien eua Veilloneila sp t r o n g d n g tCiy, n h u n g chUa t h i y t i c g i l nao dda ra cu t h e ve sd l u p n g cua chi Veilloneila sp, d i e biet la sU xuat hien va sd lUpng eCia loai V.
parvulla.
JOURNALOF 108-CUNICAL MEDICINEAND PHARMACY Vol.11-N''4/2016
Nghien cdu cCia Fabris va CS [4] d 103 rang sda hoai t d t u y thay, t ^ le cau khuan Gram (-) chiem 4 9 % cac t n r d n g hpp. Peters va CS [10], dda ra bang chdng cu t h e hon ve vi khuan nay, khi nghien cdu d 43 dng tuy rang hoai t d t h l y , ed 3 t r d d n g h p p d d d n g t i n h vdi Veilloneila sp. Trong n g h i l n edu n l y , ehung tdi chda dUa ra ddpc bang chdng eu t h e v l kha nang hay ccf che gay b i n h cda Veilloneila sp. Nhdng d d cung la m d t cau hdi m d cho e l e nghien cdu s l u hcfn v l loai vi khuan nay.
4.2.2. Micromonas micros hay cdn ggi Id Peptostreptoeoccus micros
Trong nghien cdu cua chung t d i , Micromonas micros la loai vl khuan gap nhieu t h d hai sau Veilloneila sp. chCing t d i t h a y 8/14 rang cd mat M.
micros, e h i l m ty- I I 57,1%. NhUng sd lUpng t r u n g binh tren mau ed mat vi khuan nay n h i l u hon eua Veilloneila sp (> 9,75 x 10''CFU/ml).
M. micros (Peptostreptoeoccus) la mot ehl thude cau khuan Gram (+), ky khi, cd t h e gay benh d rat nhieu eo quan trong eo the. Nd dupe chia ra thanh rat nhleu loai rieng biet, trong do loai ed mat va gay benh chCi yeu d vung rang mleng I I Peptostreptoeoccus anaerobius. Trong n g h i l n cud nay, chCing tdi mdi chl tap chung phat hien chi Peptostreptoeoccus ndi ehung ma chua di sau nghien eUu ve loai Peptostreptoeoccus anaerobius. Peters va cs [10], lai dUa ra b i n g chdng rd hem ve chi va l o l i cCia Peptostreptoeoccus, nhung t i e gia khdng dda ra eon sd cu t h i v l sd lUpng eCia vi khuan nay. Sd ca phat h i l n thay Peptostreptoeoccus trong nghien cC^ cCia Peters la 22/43 ea, trong do P.
anaerobius ed 3 ea. Mdt n g h i l n cdu khae d 15 rang m d t c h i n eua Bystrom v l CS [2] thay, P. anaerobius xuat hien d 5 rang.
4.2.3. Streptococcus oralis
La vl khuan eung t h u d n g x u l t hien t r o n g n g h i l n cdu eCia chung t d i . S. oralis cd mat d 8/14 r i n g , chiem t y le 57,1%. Sd lupng t r u n g binh tren mau cd mat vi khuan n l y > 8,94 x 1 O^CFU/ml.
S. oralis la eau khuan Gram (+), hieu ky khi t u y tien. Nd dupe phan loai n h u la m o t thanh vi^n cua n h d m S. mitis, t r o n g do vi khuan gay benh chinh d ngudi la S. pneumoniae. S. oralis dupe biet den la m d t
t r o n g n h d n g vi khu^n dau t i e n h l n h t h a n h cac mang sinh hpc m a n g b a m . M d t sd n g h i e n edu c h o t h a y S.
oralis cd t h e t u o n g t i e vdi Porphyromonas gingivalls, dugc c c i la m d t t r o n g nhCttig nguyen n h l n h a n g dau eda b e n h nha c h u ma b i n h nha ehu d u p c eoi la b e n h p h d b i l n nhat anh h u d n g den khoang mieng cua con n g u d i .
N g h i l n edu ve S. ora//s, Siqueira va CS [12] thay rang, vl khuan nay x u a t hien d 1 t r u d n g h p p trong t d n g sd 11 rang eda tOy hoai t d ddpc nghien cdu.
4.2.4. Prevotella oralis
D l y la loai vl khuan c u n g hay g a p t r o n g n g h i l n cdu, ehung t d i t h i y P. oralis xuat hien 6/14 rang, c h i e m ty' I I 42,9%. Sd Idpng v i khuan t r u n g binh t r l n m a u ed m a t P. oralis c u n g kha Idn (> 1 x 10^CFU/ml).
Nghien cdu d 43 rang t u y hoai t d cCia Peters va CS [10] t h i y , ed 7 t r d d n g h p p cd m a t P. oralis. Fabris va CS [4], khi phan t i c h vi khuan t r o n g d n g tOy hoai t d d rang sda t h a y t^ le x u a t hien cua Prevotella sp la 11,4%. Qua ket q u i n g h i l n c d u ehdng t d i t h i y rang, P. oralis I I loai vi khuan kha t h u d n g gap va cd sd lupng Idn t r o n g t u y rang hoai t d .
4.2.5. Streptococcus sanguinis
Chiing tdi t h i y cd 6/14 rang ed mat S. sanguinis, chiem t ^ le 42,8%. Sd lUcftig t r u n g binh tren mau co mat vi khuan nay > 8,25 x 10^CFU/ml.
M o t sd nghien edu ve vi khuan S. sanguinis cho ket q u i n h u s a u .
Nghien edu vi k h u l n t r o n g d n g t u y cda Sousa va CS [14] thay, t y le x u l t hien S. sanguinis ehiem 6,6%
cac t r u d n g h p p . Nghien edu lam sang cua Peters va CS [10] d 43 rang thay, S. sanguinis chi x u a t hien duy n h i t m d t t r u d n g h p p . T r o n g nghien cdu cda Siqueira va CS [12], 5. sanguinis xuat hien d 1/11 rang. Perez va CS [9] ehdng m i n h r i n g , lien cau S.
sanguinis cd t h e x l m nhap vao gde d n g nga va no ddpc eoi la m o t t r o n g n h d n g n g u y i n nhan chinh cDa t h i t bai npi nha.
4.2.6. Streptococcus mitis
Day eung la loai vi khuan xuat h i l n k h i nhieu va ^ ed sd lupng tUOng ddi Idn t r o n g ncihien cChj cOa
TAP CHI Y DLTOC U M SANG 108 Tap 11-564/2016
ehung toL Chung t d i gap d 4/14 r i n g , e h i l m t ? le 28,6%, Sd lupng 5. mitis t r u n g binh tren m l u ed mat vi khuan nay > 1,25 x 1 O^CFU/ml.
S. mitis I I l o l i vi k h u l n hieu ky khf tCiy t i e n , chiing t h u d n g b I m vao e l e be mat edng eCia khoang mieng n h u m i n g bam rang va c l e m d euYig cua rang, it g l y benh v u n g rang m i l n g nhdng cd t h e g l y n h i l m trUng h u y l t , v i l m ndi tam mac.
Cac tai lieu nghien cdu vl khuan t r o n g rang mleng trude day, rat it cac tac gia di sau nghien cdu ve S. mitis, m d t sd tac gia cd de e l p den loai vi khuan n l y nhdng d mde dp rat han che. Sousa va cs [14], khi nghien cdu vi khuan t r o n g d n g t u y rang d benh n h l n bi ap xe t h i y 20% sd rang cd su xuat hien cOa 5. mitis. Siqueira va cs [12], thay 5. mitis xuat hien d 1 trudng hpp, khi nghien edu lam sang d 11 rang viem quanh cudng man.
4.2.7. Enteroeoccus faecalis
Ket q u i n g h i l n edu thay E. faecalis xuat hien d 3/14 rang, ehlem t y I I 21,4%. so Idpng t r u n g binh tren mau ed mat E. faecalis > 4,33 x 10'CFU/ml.
f. faecalis t h u d c chl Enteroeoccus, la cau khuan Gram (+), ky khi tuy y. Vi khuan nay tuy khdng xuat h i l n n h i l u , n h d n g n d ddpc col la nguyen nhan chu yeu cua that bai t r o n g dieu tri ndi nha. Chinh vl vay, E. faecalis la ddi t d p n g eua rat nhieu cac nghien cdu, nhUng eae t i e g i l dua ra c l e y k i l n khdng d d n g nhat tham chi trai ngupe nhau.
Molander va cs [5], khi nghien cdu vi k h u l n trong dng tCiy d 100 rang tCiy hoai t d thay, t J le xuat hien cCia £ faecalis chiem 32% cac t r u d n g hpp.
Sundqvist v l es [15] nhan thay, t^ le d u o n g tfnh vdi E. faecalis d nhdng rang dieu t n t u y that bai la 38%.
Nghien cdu eCia Ozbek va cs [7] t h i y r i n g , t r o n g sd 36 r i n g viem quanh cudng man thi ed 9 r i n g cd mat
£ faecalis, ehlem t ^ le 25% va t r o n g 43 rang dieu tri tuy that bai ed 32 rang ed sUxuat h i l n eua £ faecalis, chiem t ^ le 74,4%. Nghien cdu cCia Fabris va cs [4] lai thay, ty le vl khuan Enteroeoccus c h i l m t d i 50% cac trudng hpp. Tuy nhien, tac gia tien hanh nghien cdu tren rang sda va dUa ra ty- le vi khuan Enteroeoccus ndi ehung c h d khdng chi ra eu t h e ve loai E. faecalis.
Sjogren va cs [13], khi nghien cdu d 18 rang viem
quanh c u d n g thay, ed 3/18 t r d d n g h p p cd m a t £ faecalis. Perez va es [9] bao cao r i n g , £ faecalis la tac n h l n g l y b e n h n h d n g ddc lUc t h a p .
5. K e t l u a n
Qua nghien cCiXi so l u p n g va sU ed m a t cDa m d t sd loai vi khuan t r o n g b i n h ly tCiy rang hoai t d , c h d n g t d i n h l n t h i y hau het c l e d n g t d y d e u cd vl khuan vdi sd lupng vi khuan t r u n g b i n h t r o n g d n g t u y > 4,11 x 10^CFU/ml. M d t sd l o l l vi khuan t h u d n g xuyen cd mat t r o n g d n g t d y la Veilloneila sp (71,4%), S.oralis, M.micros (57,1%). M o t so loai cd sd Idpng vi khuan t r u n g b i n h tren mau dUOng t f n h eao nhat la 5.m/f/s (> 1,25 X lO'CFU/ml), P. oralis (> 1 x 10^
CFU/ml). Do d d , v i l e dieu trj ndi nha rang tCiy hoai t d can c h u t r p n g t d i van de sat khuan, lam saeh d n g tuy, n h a m m a n g lai hieu q u i t d i Uu eho ngudi b e n h .
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4. Fabris AS, Nakano V et al (2014) Bacteriological analysis of necrotic pulp and fistuloe in primary teeth. J. Appl. Oral Sci 22(2): 118-124.
5. Molander A,Reit C et al (1998) Microbiological status of root-filled teeth with apical periodontitis.
lnt.Endod.J31(1):1-7.
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