I HC HU

TRNG I HC Y DC

TRN TN TI

THC TRNG BNH SU RNG V HIU QU

CA GII PHP CAN THIP CNG NG CA HC SINH

TI MT S TRNG TIU HC THA THIN HU

LUN N TIN S Y HC

HU - 2016

I HC HU

TRNG I HC Y DC

TRN TN TI

THC TRNG BNH SU RNG V HIU QU

CA GII PHP CAN THIP CNG NG CA HC SINH

TI MT S TRNG TIU HC THA THIN HU

Chuyn ngnh: Y T CNG CNG

M s: 62 72 03 01

LUN N TIN S Y HC

NGI HNG DN: 1. PGS.TS. LU NGC HOT

2. PGS.TS. NGUYN TOI

HU - 2016

Li Cm n

Ti xin chn thnh cm n i hc Hu, Ban Gim hiu, Phng Sau

i hc Trng i hc Y Dc Hu to mi iu kin cho ti hc tp

v nghin cu.

Ti xin t lng bit n su sc ti PGS.TS Lu Ngc Hot, PGS.TS

Nguyn Toi l nhng ngi Thy tn tnh hng dn, gip , ngy

m trn tr cng ti trong sut qu trnh lm lun n.

Ti xin chn thnh cm n PGS.TS V Vn Thng, Trng khoa Y T

Cng Cng cng cc ging vin, nhn vin trong khoa gip ti rt

tn tnh, chu o trong sut thi gian hc tp v nghin cu.

Ti xin cm n Ban ch nhim v cn b Khoa Rng Hm Mt, Khoa

TMH - Mt - RHM to mi iu kin cho ti c hc tp v hon

thnh lun n.

Ti xin cm n su sc n phng Gio dc thnh ph Hu, phng

Gio dc huyn Nam ng v Ban Gim hiu cng Thy C gio cc

trng tiu hc: Ph Ha, Quang Trung, Khe Tre, Thng L, Hng

Ha, Hng Ph. c bit xin cm n s cng tc nhit tnh ca qu ph

huynh cng cc em hc sinh, cc cng tc vin, cc Bc s v sinh vin

Rng Hm Mt, Y T Cng Cng trc tip gip ti trong qu trnh t

chc thu thp s liu v trin khai cc hot ng can thip ti cng ng.

Cui cng, xin c gi tm lng n tnh ti gia nh, v v cc con,

ni hng ngy ti nhn c s cm thng, chia s, gip v mong mi

cho ti hon thnh cng trnh ny.

Tc gi

TRN TN TI

LI CAM OAN

Ti xin cam oan y l cng trnh nghin cu ca ring ti.

Cc s liu, kt qu trong lun n ny l trung thc v cha

tng c cng b trong bt k cng trnh nghin cu khoa hc

no khc. Nu c sai st g, ti xin hon ton chu trch nhim.

Nghin cu sinh

Trn Tn Ti

K HIU VIT TT

CSCT Ch s can thip

CSHQ Ch s hiu qu

CSRM Chm sc rng ming

GDNK Gio dc nha khoa

GDSK Gio dc sc khe

HQCT Hiu qu can thip

HS Hc sinh

NH Nha hc ng

RM Rng ming

SKRM Sc khe rng ming

SL S lng

smtr Su mt trm rng sa

SMTr Su mt trm rng vnh vin

TCYTTG T chc Y t Th gii

TH Tiu hc

TP Thnh ph

VSRM V sinh rng ming

MC LC

MC LC

DANH MC CC BNG

DANH MC CC BIU , S , HNH V

T VN ............................................................................................................. 1

Chng 1: TNG QUAN TI LIU ......................................................................... 5

1.1. C IM GII PHU SINH L CA RNG .............................................. 5

1.1.1. c im gii phu rng ........................................................................... 5

1.1.2. Sinh l mc rng ....................................................................................... 7

1.2. SINH BNH HC, DCH T HC SU RNG V CC YU T NGUY

C CA BNH SU RNG..................................................................................... 8

1.2.1. Sinh bnh hc bnh su rng ..................................................................... 8

1.2.2. Dch t hc bnh su rng ....................................................................... 15

1.2.3. Cc yu t nguy c gy su rng ............................................................ 21

1.3. HU QU CA BNH SU RNG ............................................................... 22

1.3.1. V sc khe rng ming .......................................................................... 22

1.3.2. V kinh t x hi ..................................................................................... 22

1.4. VAI TR CA FLUOR TRONG NHA KHOA ............................................... 23

1.5. CC BIN PHP CAN THIP TRONG CNG NG D PHNG

SU RNG .............................................................................................................. 25

1.5.1. C s khoa hc hnh vi ca truyn thng gio dc sc khe ti cng

ng............................................................................................................ ...... 25

1.5.2. Chin lc d phng bnh su rng........................................................ 27

1.5.3. Cc bin php can thip ca TCYTTG .................................................. 29

1.5.4. Chng trnh Nha hc ng ti Vit Nam ............................................ 31

1.6. CC NGHIN CU LIN QUAN TRONG VIC PHNG CHNG BNH

SU RNG TRONG NC V QUC T. ......................................................... 34

1.6.1. Ti Vit Nam ........................................................................................... 34

1.6.2. Ti nc ngoi ........................................................................................ 37

Chng 2: I TNG V PHNG PHP NGHIN CU ............................ 41

2.1. I TNG NGHIN CU ........................................................................... 41

2.2. THI GIAN NGHIN CU ............................................................................. 41

2.3. PHNG PHP NGHIN CU ...................................................................... 41

2.3.1. Thit k nghin cu:................................................................................ 41

2.3.2. C mu nghin cu ................................................................................. 44

2.3.3. Chn mu nghin cu ............................................................................. 49

2.3.4. Cc bc nghin cu ............................................................................... 51

2.3.5. Cc phng php c th .......................................................................... 52

2.3.6. Cc ch s nh gi ................................................................................. 61

2.4. PHN TCH V X L S LIU .................................................................. 66

2.4.1. Phn tch s liu nh lng .................................................................... 66

2.4.2. Phn tch s liu nh tnh ....................................................................... 67

2.5. K THUT KHNG CH SAI S ................................................................. 67

2.6. CC HN CH CA NGHIN CU ............................................................. 67

2.7. O C NGHIN CU ............................................................................... 68

Chng 3: KT QU NGHIN CU ..................................................................... 69

3.1. T L MC BNH SU RNG V MT S YU T NH HNG 69

3.1.2. Thc trng mc bnh su rng v mt s bnh rng ming lin quan

trn i tng nghin cu ................................................................................. 69

3.1.2. Xc nh mt s yu t nh hng n bnh su rng ........................... 74

3.2. V GII PHP CAN THIP V HIU QU CA MT S M HNH

CAN THIP C S THAM GIA CA CNG NG .......................................... 82

3.2.1. M hnh can thip t nghin cu bnh-chng v nghin cu nh

tnh ..................................................................................................................... 82

3.2.2. nh gi hiu qu can thip .................................................................... 83

Chng 4: BN LUN .......................................................................................... 103

4.1. T L MC BNH SU RNG V MT S YU T NH HN 103

4.1.1. V c im chung trn i tng nghin cu ..................................... 103

4.1.2. V t l su rng .................................................................................... 103

4.1.3. V cc yu t nh hng n bnh su rng ......................................... 108

4.2. V GII PHP CAN THIP V HIU QU CA MT S M HNH

CAN THIP C S THAM GIA CA CNG NG ........................................ 121

4.2.1. V hiu qu can thip d phng ca hai nhm nghin cu c so snh

vi nhm chng khng can thip ............................................................................ 122

4.2.2. V cc yu t nh hng n hiu qu can thip phng su rng ........ 128

4.3. NG GP MI CA NGHIN CU ..................................................... 141

KT LUN ............................................................................................................. 142

KIN NGH ............................................................................................................ 145

DANH MC CC CNG TRNH KHOA HC LIN QUAN

TI LIU THAM KHO

PH LC

DANH MC CC BNG

Bng 1.1. Phn chia mc su rng theo ch s SMT ca TCYTTG ................... 15

Bng 3.1. S lng hc sinh c khm theo Trng ............................................. 69

Bng 3.2. Phn b i tng hc sinh nghin cu ................................................... 70

Bng 3.3. T l mc cc bnh lin quan n su rng trn cc i tng nghin cu ..... 71

Bng 3.4. T l mc bnh su rng trn cc i tng nghin cu .......................... 72

Bng 3.5: Ch s su, mt, trm ca rng sa (smt) v rng vnh vin (SMT) ......... 73

Bng 3.6. Phn b cc cp nghin cu Bnh Chng theo tiu ch ghp cp ......... 74

Bng 3.7. Cc yu t lin quan n su rng (m hnh hi quy logistic a bin) 75

Bng 3.8. Mi quan h nhn qu gia kin thc phng chng v bnh su rng trn

cc i tng nghin cu .......................................................................................... 76

Bng 3.9. Kin thc tng hp v su rng ca i tng nghin cu ...................... 77

Bng 3.10. Mi quan h nhn qu gia thc hnh chm sc rng ming v

bnh su rng trn cc i tng nghin cu .......................................... 79

Bng 3.11. So snh im thc hnh chm sc rng ming ca i tng nghin cu .... 80

Bng 3.12. Yu t v hon cnh gia nh v thi quen n ung .............................. 82

Bng 3.13. Ni dung can thip cc nhm nghin cu ........................................... 83

Bng 3.14. So snh vn rng ming trc can thip nhm khng su rng ..... 84

Bng 3.15. So snh vn rng ming sau can thip nhm khng su rng ........ 84

Bng 3.16. Ch s hiu qu v hiu qu can thip nhm khng su rng ............. 85

Bng 3.17. So snh vn rng ming trc can thip nhm su rng ................ 86

Bng 3.18. So snh tnh trng su rng sau can thip hai nhm su rng c

iu tr ....................................................................................................................... 87

Bng 3.19. So snh vn rng ming sau can thip nhm su rng ................... 87

Bng 3.20. Ch s hiu qu v hiu qu can thip nhm su rng ........................ 88

Bng 3.21. Tnh trng li rng ................................................................................. 89

Bng 3.22. Tnh trng cao rng ................................................................................. 89

Bng 3.23. Tnh trng mng bm .............................................................................. 90

Bng 3.24. Vn rng ming trc can thip ......................................................... 90

Bng 3.25. im kin thc v thc hnh chm sc rng ming ............................... 91

Bng 3.26. Kin thc v thc hnh chm sc rng ming ....................................... 91

Bng 3.27. Thc hnh chm sc rng ming lin quan n hiu qu phng bnh

su rng .................................................................................................... 92

Bng 3.28. Mt s yu t nh hng n hiu qu phng bnh su rng ................ 94

Bng 3.29. Cc yu t lin quan n hiu qu phng bnh su rng ........................ 95

Bng 3.30. im kin thc v thc hnh chm sc rng ming lin quan n

hiu qu phng vim li .......................................................................... 96

Bng 3.31. Thc hnh lin quan n hiu qu phng vim li ................................ 96

Bng 3.32. Mt s yu t khc nh hng n hiu qu phng vim li ................. 97

Bng 3.33. im kin thc v thc hnh chm sc bnh rng ming lin quan

n hiu qu phng cao rng ................................................................... 98

Bng 3.34. Thc hnh chm sc rng ming lin quan n hiu qu phng cao rng .... 98

Bng 3.35. Mt s yu t khc nh hng n hiu qu phng cao rng ................ 99

Bng 3.36. im kin thc v thc hnh chm sc rng ming lin quan n

hiu qu phng mng bm ..................................................................... 100

Bng 3.37. Thc hnh chm sc rng ming lin quan n hiu qu phng

mng bm ............................................................................................... 101

Bng 3.38. Mt s yu t khc nh hng n hiu qu phng mng bm ........... 102

DANH MC CC S , HNH

S 2.1. Mi lin quan gia 3 thit k nghin cu v mc ch ca tng thit k ........ 42

S 2.2. Ba giai on thit k ca nghin cu: Ct ngang - Bnh chng - Can

thip (c kt hp gia nghin cu nh lng v nh tnh) ................... 43

S 2.3. Phn b c mu cho tng giai on nghin cu ...................................... 48

S 2.4. Cc trng tiu hc tham gia nghin cu ................................................ 51

S 2.5. M hnh can thip trn i tng nghin cu ......................................... 58

S 2.6. S nh gi hiu qu ca s can thip thng qua Ch s hiu qu ..... 66

Hnh 1.1. Cu trc rng .............................................................................................. 5

Hnh 1.2. Khi nim v qu trnh su rng ca Pitts NB ............................................ 9

Hnh 1.3. S Keyes S phi hp c 3 yu t gy su rng. S White .......... 12

Hnh 1.4. Lin quan gia cc yu t bnh cn-lp lng vi khun v rng v cc

thnh phn sinh hc(vng trn bn trong) v cc yu t hnh vi v

kinh t -x hi (vng trn ngoi) ............................................................. 15

1

T VN

Bnh su rng l bnh kh ph bin, gy hu qu nhiu mc v sc kho

rng ming v sc kho chung. Bnh su rng c T chc Y t Th gii (World

Health Organization) xp vo loi tai ha th ba ca loi ngi sau bnh ung th v

tim mch [171].

Thng 5 nm 2007, ti hi ngh sc khe rng ming th gii l n th 60, cc

nc thnh vin ca T chc Y t Th gii th ng qua ngh quyt, a x c tin v

ph ng ng a bnh su rng vo quy hoch ph ng ng a v iu tr tng hp bnh m n

t nh [138]. Hin nay, sc khe rng ming l mt trong 10 tiu chu n ln v sc khe

theo s xc nh ca T chc Y t Th gii. V vy, vic chm s c, d ph ng bnh

su rng l mt vn ln c ch nh ph cc nc quan tm [101], [121].

Theo kt qu iu tra sc khe rng ming ton quc nm 1999-2000 ca Vin

Rng Hm Mt H Ni, hn 50% tr em trn 8 tui b cao rng, 60 - 80% tr b su rng

sa, t l su rng vnh vin tng theo tui, ti 69% la tui 15 - 17 [53]. Trc y,

B Y T c ng b cc ch nh sch nh nc v chm s c sc khe rng ming cho

nhn dn n nm 2010 nhm y mnh vic th c hin 6 chng tr nh mc tiu, trong

c chng tr nh s dng fluor, fluor ho nc ung. Cc chng tr nh ny gip gp

ph n h thp t l bnh rng ming v t c mc tiu ra n nm 2010, l gim

t l bnh rng ming trn 50%. Tuy nhin, tng kt chng tr nh nha hc ng nm

2007 ca Bnh vin Rng Hm Mt thnh ph H Ch Minh ghi nhn mt con s bo

ng: t l su rng hc sinh 12 tui hin nay l 50%. Thng k t Cc Y t d ph ng

nm 2011 cng cho thy trn 80% hc sinh tiu hc Vit Nam mc cc bnh rng ming

nh su rng, vim quanh rng, la tui ln hn t l ny cng ln n 60-70% v

ang c du hiu tng ln trong thi gian g n y [7], [12], [13], [42].

c bit, la tui hc sinh tiu hc l la tui m tr bt u mc rng vnh

vin, cha th c s c cu tr c rng hon thin, cha t thc c vn chm s c

sc khe rng ming, ng thi trn hai hm hin din c rng sa v rng vnh vin

2

(b rng hn hp), do t l su rng, vim li, mt rng sa sm la tui ny c n

cao. Vic mt rng sa sm, lm tr n nhai k m, pht m kh ng chu n, hm rng vnh

vin d b x lch nh hng n s pht trin th m m v th cht trong giai on sau

ny [28], [31].

Vit Nam, trong nhng nm g n y c nhiu nghin cu v t nh h nh su

rng v tr em mu gio, tiu hc, trung hc c s v nhng yu t nh hng [5], [18],

[32], [39], [56] nhm pht hin tr mc bnh iu tr, can thip v kin ngh mt s

gii php can thip cng ng nh cc chng tr nh gio dc sc khe rng ming, ch

n hp l, thm khm nh k nhm thay i hnh vi chm s c sc khe rng ming

cho tr t g p ph n h thp t l bnh su rng [16], [41], [52].

Ti Th a Thin - Hu, cng vi 63 tnh thnh trong c nc, chng tr nh

Nha hc ng c trin khai t nhiu nm nay. Tuy nhin, t l tr mc bnh

su rng vn cao, t l cc bnh v rng ming trong ton dn ngy cng gia tng

[6], [11], [49].

Th c trng ny t ra vn l phi chng cch t chc th c hin ca

chng tr nh cha ph hp hay v thc ca ngi dn cha cao? Ngoi ra, cc yu

t nh hng n bnh v d ph ng bnh rng ming ca hc sinh ph thuc rt

nhiu vo s hiu bit, cc bin php gio dc ca cha m, nh trng, cc phong

tc, tp qun v th i quen n ung, v sinh rng ming ca hc sinh, do vy, yu t

nguy c v hiu qu ca cc bin php can thip c th thay i, din bin khc

nhau theo cc vng, min khc nhau.

Ngoi ra, qua tham kho ti liu ca nhiu nghin cu su rng c can

thip cng ng ti Vit Nam [10], [14], [52], th ph n ln cc nghin cu p

dng thit k iu tra ct ngang (cross-sectional survey) v a xc nh t l

su rng, v a xc nh ln v mc ngha thng k ca mi quan h nhn

qu gia su rng v mt s yu t nh hng, t chn gii php can thip

d a trn kt qu ca mi quan h nhn qu pht hin c t iu tra ct ngang

ny. Loi thit k nghin cu m t ct ngang ny c u im l cho ph p xc

nh c t l hin mc ca mt vn sc kho trong mt qu n th nghin

3

cu no (nu mu c chn i din vi c mu ln), nhng c hn ch

l ch cho ph p h nh thnh c gi thuyt quan h nhn qu gia bnh v cc

yu t lin quan, ch kh ng cho ph p kim nh gi thuyt nh trong cc thit k

nghin cu phn tch (bnh chng hoc thu n tp), do vy cc gii php can

thip xut t nghin cu m t ct ngang s kh ng tin cy so vi cc

gii php c xut t nghin cu phn tch.

T nhng nhn thc nu trn, ch ng t i tin hnh nghin cu ti Thc

trng bnh su rng v hiu qu ca gii php can thip cng ng ca hc sinh

ti mt s trng tiu hc Tha Thin Hu nhm cc mc tiu sau:

1. Xc nh t l su rng v mt s yu t nh hng ca hc sinh ti mt s

trng tiu hc Th a Thin Hu nm 2014.

2. Xc nh mt s gii php can thip v nh gi hiu qu ca mt s m

hnh can thip c s tham gia ca cng ng nhm hn ch bnh su rng

hc sinh thuc a bn nghin cu.

ngha khoa hc v ngha thc tin ca ti

t c 2 mc tiu nghin cu trn, ch ng t i p dng 4 loi thit k trong 3

giai on nghin cu, c th l:

1. Giai on 1: l giai on iu tra ct ngang nhm xc nh t l mc su rng trong

hc sinh ang hc ti cc trng tiu hc c l a chn vo nghin cu v chn ra

c nhm hc sinh su rng v kh ng b su rng phc v cho cc loi thit k

nghin cu tip theo.

2. Giai on 2: c trin khai tip theo ngay vi giai on 1. y l mt thit k

nghin cu bnh chng ghp cp gia nhm hc sinh b su rng v kh ng b su

rng c xc nh t giai on iu tra giai on 1 kim nh gi thuyt v mi

quan h nhn qu gia mt s yu t nguy c vi bnh su rng, t xut cc

gii php can thip thch hp vi cc gi thuyt c kim nh. Ngoi ra chng

ti cn trin khai mt nghin cu nh tnh nhm tho lun vi b m hc sinh v cc

th y c gio xem cc gii php can thip ra t nghin cu bnh chng ghp cp

c kh thi trin khai hay khng? Nu kh thi th c n lu nhng im g?

4

3. Giai on 3: l giai on can thip v nh gi hiu qu ca can thip

Can thip cho c nhm hc sinh su rng v kh ng su rng theo thit k can thip

c c nhn v cng ng ngu nhin c i chng d a trn cc gii php can thip

xc nh t giai on trc;

nh gi hiu qu ca cc gii php can thip thng qua so snh t l mc su rng

gia nhm can thip v nhm chng sau can thip v nh gi can thip thng qua

Ch s hiu qu ca can thip. Ngoi ra chng ti cn tin hnh nghin cu nh

t nh trong giai on ny nhng trng hp can thip thnh cng v can thip tht

bi t rt ra cc bi hc t cc gii php can thip ny.

Chng ti hy vng rng nghin cu khng ch d ng li vic xut v th

nghim mt m hnh lng ghp nhiu loi thit k trong mt nghin cu sc khe cng

ng m cn gp ph n xy d ng m h nh chm s c sc khe ban u, vi chng tr nh

Nha hc ng ca Th a Thin Hu ni ring v ca ton quc ni chung, t g p

ph n gim bnh l su rng xung c n 50% nh xut trong mc tiu quc gia v

chm s c rng ming cho ton dn.

5

Chng 1

TNG QUAN TI LIU

1.1. C IM GII PHU SINH L CA RNG

1.1.1. c im gii phu rng

Rng l 1 b phn nm trong h thng nhai. H thng nhai: bao gm rng, nha

chu, xng hm, khp thi dng hm, cc c nhai, cc dy th n kinh, mch mu,

h thng tuyn nc ming, h thng m i m li.

C quan rng l mt n v cu to v chc nng ca b rng, bao gm rng

v nha chu: rng l b phn ch nh, tr c tip nhai nghin thc n, gm men rng, ng

rng v ty rng. Mi rng c ph n thn rng v chn rng. Gia ph n thn rng v

chn rng l ng c rng (c rng gii phu), c n gi l ng ni men-x mng.

Thn rng c bao bc bi men rng, chn rng c x mng bao ph [23], [48],

[129].

Hnh 1.1. Cu trc rng [109]

[Ngun: International Federation of Dental Educators and Association, 2010]

Men rng Ng rng

Ty rng Li rng

Chn rng Dy chng

Xng rng X mng

chn rng

6

Li rng bao quanh c rng to thnh b, gi l c rng sinh l. Ph n rng thy

c trong ming l thn rng lm sng. Thn rng bao gm men, ng rng (m

cng) v ty rng (m mm).

- Men rng: c ngun gc ngoi b , l t chc cng nht c th. Lp men ph thn

rng thng dy mng kh ng u, ch dy nht l n m rng (hn 1,5mm), vng

c, men rng mng d n v tn cng bng mt cnh g c nhn. Bn ngoi men rng

c ph mt lp hu c: gi l mng th pht.

L c rng mi mc, men rng c n non, c ti 30% cht hu c v nc. D n

d n men rng gi i, cht v c tng d n, c th l do cc tinh th sp xp li st

nhau hn, mt khc men rng cng ngm cc cht vi lng ch yu l fluor lm cho

apatit chuyn thnh fluoroapatit.

Men bao ph thn rng, h u nh kh ng c cm gic.

- Ng rng: l mt t chc chim khi lng ch yu thn rng, trong iu kin

b nh thng ng rng kh ng l ra ngoi, v c bao ph hon ton bi men rng

v xng rng. Ng rng t cng hn men rng, gm 70% v c, 30% hu c v n-

c, ng lin tc t thn n chn rng, tn cng ch p rng (apex), trong l ng

cha bung ty v ng ty. Ng c cm gic v cha cc ng th n kinh Tomes.

Ng rng cng nht c thy khong cch ty 0,4 n 0,6mm cho ti khong

gia lp ng, g n ty, ng rng mm hn, vng ngoi vi tng i mm. Ng rng

t nhin c mu vng nht, c n hi cao. Ng rng xp v c t nh thm.

- Ty rng: l m lin kt lng lo trong bung v ng ty, l n v sng ch yu

ca rng. Trong ty c mch mu, th n kinh, bch mch...C mt loi t bo c

bit l cc to ng bo xp thnh mt hng st vch ty. Cc to ng bo lin tc

to ra ng bo (ng th pht) lm cho hc ty ngy cng hp li.

Ty rng c 4 nhim v: (1) h nh thnh ng rng, (2) nu i dng ng rng,

men rng, (3) dn truyn cm gic nh cc dy th n kinh vi cc u tn cng st

vch ty hoc chui vo cc ng ng. Cm gic ca rng qua h thng ty l rt c

bit v : kh ng c hiu v v tr , kh ng c hiu v nguyn nhn gy ra cm gic,

(4) Bo v rng [23], [48], [109], [129].

7

1.1.2. Sinh l mc rng

S mc rng g p ph n quan trng trong vic h nh thnh khu n mt, gi p hon

thin s pht m v chc nng nhai. Cc m m rng c h nh thnh t trong xng

hm, l n lt di chuyn v mt ph n thot ra khi cung hm, ch nh l ph n thn

rng nh n thy trong xoang ming.

S mc rng bt u t khi thn rng c h nh thnh v tip din trong sut

i ca rng. Rng mc ln c, mt ph n do chn rng cu to di ra, mt ph n

do s tng trng ca xng hm. Khi chn rng cu to hon tt, rng vn tip

tc mc ln c, nh vo s bi p lin tc cht x mng ch p chn rng.

Mi rng c lch thi gian mc v v tr nht nh trn cung hm, nh vy cc

rng hm trn v di sp xp th t v n khp vi nhau. Chn rng c cu

to d n d n v hon tt sau 3 nm k t thi im rng mc (hin tng ng

ch p). Tui ng ch p = tui mc rng + 3. C hai thi k mc rng:

- Thi k mc rng sa: Rng sa mc vo trong khoang ming khong thng th 6

sau khi sinh. n 2 hoc 3 tui, tr em c b rng sa gm 20 rng (10 rng hm

trn v 10 rng hm di).

Ngoi chc nng n nhai, pht m, rng sa ng vai tr quan trng trong vic

pht trin ca xng hm v gi ng v tr cho rng vnh vin mc ln sau ny.

Chn rng sa tiu d n khi i n tui thay, rng vnh vin thay th mc d n ln th

vo v tr rng sa.

Tr em t 6-11 tui hin din c rng sa v rng vnh vin trn cung hm, gi

l rng hn hp (denture mixte).

- Thi k mc rng vnh vin: M m rng vnh vin, mt s c h nh thnh trong

thi k bo thai, t thng th 3 n 5, s c n li h nh thnh sau khi sinh n thng

th 9. Ring m m rng kh n l c 4 tui. Rng vnh vin c lng ng cht men,

ng (s khong h a) bt u t l c sinh ra n 6 - 7 tui. Ring m m rng kh n l c

10 tui. Rng vnh vin bt u mc thay th d n rng sa khi tr c 6 tui.

Khi tr 12 - 13 tui, tt c rng sa s c thay th bng rng vnh vin.

Lc 17 - 21 tui c b rng vnh vin gm 32 rng [24], [28], [31].

8

- Cc yu t nh hng n s mc rng:

+ Chiu cao v cn nng: Tr cao v mp, rng mc sm hn tr thp v g y.

+ Gii t nh: N mc sm hn nam.

+ K ch thc xng hm: Hm rng, rng mc sm v tha, hm hp,rng

mc chm v chen ch c.

+ Rng sa: Rng sa rng sm hoc chm s lm chm mc rng vnh vin.

+ Dinh dng: Dinh dng k m s lm rng mc chm (bnh c i xng).

+ Vim nhim xng hm: Xng hm b vim nhim trong thi k mc rng

s lm rng mc sm.

+ Yu t di truyn: Mt trong nhng nguyn nhn ch nh khin tr chm mc

rng so vi tui l do gen di truyn. Tr s th a hng nhng c im v h nh

dng ln cu tr c bn trong c th t b m [31], [59], [88].

1.2. SINH BNH HC, DCH T HC V CC YU T NGUY C CA

BNH SU RNG

1.2.1. Sinh bnh hc bnh su rng

1.2.1.1. nh ngha v chn on bnh su rng

- nh ngha: Bnh su rng l mt bnh nhim khu n ca t chc canxi h a c

c trng bi s hy khong ca thnh ph n v c v s ph hy thnh ph n hu c

ca m cng [2], [48].

Tn thng su rng l qu trnh phc tp bao gm cc phn ng ha l lin

quan n s di chuyn cc ion b mt gia rng v m i trng ming, l qu trnh

sinh hc gia cc vi khu n mng bm vi c ch bo v ca vt ch.

- Chn on su rng trong cng ng:

+ Khi nim qu tr nh su rng theo h nh nh minh ha tng bng tr i ca Pitts

NB. (2004) [141]: l tng bng chia lm 4 mc tin trin su rng (hnh 1.2)

D1: Tn thng men rng vi b mt c n nguyn vn, c th pht hin trn

lm sng.

D2: Tn thng men rng c to xoang, c th pht hin trn lm sng.

9

D3: Tn thng ng rng, c th pht hin trn lm sng.

D4: Tn thng vo ty rng.

Tn thng hai t ng di l su rng giai on sm, kh ng th pht hin

c, phi nh phng tin h tr hoc nh ch n on hin i. Su rng giai

on sm c th hi phc hon ton nu c can thip v ti khong kp thi m

kh ng c n khoan trm. H nh nh tng bng tr i gi p phn bit cc giai on tin

trin ca su rng, mc ni ca tng bng ty thuc vo ngng ch n on v

mc ch s dng ca cc nghin cu.

Ngng ch n on t D3 c dng cho cc nghin cu dch t hc, su rng

c xc nh khi tn thng vo ng rng.

Ngng ch n on t D1 dnh cho cc th nghim v nghin cu v th c

hnh lm sng, qua c cc bin php d ph ng v iu tr th ch hp [141].

Hnh 1.2. Khi nim v qu trnh su rng ca Pitts NB. [141]

[Ngun:Pitts NB.(2001)]

+ Ch n on su rng theo TCYTTG:

- Rng c nh gi lnh mnh khi kh ng c du hin no ca xoang su, ming

trm hoc Sealant.

- Tiu chu n l su theo TCYTTG nm 1997: R nh trng trn mt nhai, ngoi,

trong gi l su khi mc thm trm l c thm khm, n thm trm vo vi l c v a

phi km vi cc du chng su rng khc nh:

y c l su mm.

10

C vng c xung quanh ch mt khong.

C th dng thm trm co i ng mm vng xung quanh

Vng c do mt khong m cha c ng mm vn c xem l rng lnh

mnh

- Tiu chu n xoang su c quy nh theo TCYTTG nm 2005, quy nh cho h

thng nh gi ICDAS (International Caries Detection and Assessment System):

Tiu chun pht hin su thn rng nguyn pht theo ICDAS [9]

M s M t

0 Lnh mnh

1 m trng c (sau khi thi kh 5 giy)

2 i mu trn men (rng t)

3 V men nh khu (kh ng thy ng)

4 B ng en nh ln t ng

5 Xoang su thy ng

6 Xoang su thy ng lan rng (>1/2 mt rng)

1.2.1.2. c im su rng tr em tiu hc

La tui hc sinh tiu hc l la tui m tr bt u mc rng vnh vin, cha

th c s c cu tr c rng hon thin, trn hai hm hin din c rng sa v rng vnh

vin (b rng hn hp).

Su rng sa xut hin tr cha hoc bt u thay sang rng vnh vin, y

l la tui bt u vo lp 1. Tnh trng su rng sa cng c th xut hin trc

khi tr n trng. c im ca rng sa l kt cu khng bn vng, mm v d b

tc ng ca vi khu n trong ming, do vy rng sa rt d b su. Nu kh ng c

iu tr tt, rng sa b su s ly lan sang cc rng lnh khc v l iu kin thun

li lm cho cc rng vnh vin mc sau tip tc mc phi cn bnh ny [28].

Song hnh cng vi bnh su rng sa l tnh trng vim li. y l 2 bnh

c quan h vi nhau. Khi li b vim s v sng ty, d chy mu, ming c mi

hi. V li b au nn nhiu tr khng chu nh rng thng xuyn lm cho tnh

trng vim tip tc nng hn v to iu kin cho su rng pht trin. Bn cnh ,

11

tnh trng thay rng kh ng c chm s c tt, su rng, mt rng, lm cho nhiu tr

c hm rng vnh vin mc lch lc, nh hng n th m m v c n l iu kin

cho mng bm, vi chi rng kh ng lm sch c s gy ra cc bnh rng ming

(RM) sau ny [31], [59], [48].

1.2.1.3. Bnh nguyn su rng

Tn thng su rng ch xy ra di mt m vi khu n c kh nng to

lng acid ti ch lm mt khong cu tr c rng. Khi gelatin vi khu n d nh vo

b mt rng c gi l mng bm. Mng bm vi khu n bin dng carbohydrate

tinh ch cho nng lng v acid hu c nh mt sn ph m ph.

Sn ph m acid c th l nguyn nhn ca tn thng su rng bi s h a tan

nhng tinh th cu tr c rng. Su rng tin trin t ng t l c mnh l c yu ty theo

mc pH trn mt rng vi s thay i bin dng ca mng bm. Su rng hot

ng mnh thi k hot ng bin dng ca vi khu n cao v pH ti ch gim

di 5,5. Cc ion Ca2+

v PO43-

trong nc bt gi nhim v lm ngun cung cp

nguyn vt liu cho tin trnh ti khong ha.

Bnh su rng l mt bnh a nguyn nhn, trong vi khu n ng vai tr

quan trng. Ngoi ra c n phi c cc yu t thun li nh ch n ung nhiu

ng, v sinh rng ming (VSRM) kh ng tt, t nh trng sp xp ca rng khp

khnh, cht lng men rng k m v m i trng t nhin, nht l m i trng nc

ung c hm lng fluor thp to iu kin cho su rng pht trin [31],[79], [81].

1.2.1.4. Bnh sinh

Trc nm 1970, ngi ta cho rng bnh cn ca su rng l do cht ng, vi

khu n Streptococcus Mutans v gii th ch nguyn nhn su rng bng s Keyes.

Theo s Keyes, vic ph ng bnh su rng tp trung vo ch n hn ch

ng, tin hnh VSRM k song kt qu ph ng bnh su rng vn b hn ch [164].

Sau nm 1975 ngi ta lm sng t hn cn nguyn bnh su rng v gii

th ch bng s White thay th mt v ng tr n ca s Keyes (cht ng) bng

v ng tr n cht nn (substrate) nhn mnh vai tr nc bt (cht trung ho - Buffers)

12

v pH ca d ng chy m i trng quanh rng.

A) Su rng (B)

Hnh 1. 3. (A) S Keyes S phi hp c 3 yu t gy su rng (B) S White

[Ngun: Usha C. and Sathyanarayanan R (2009)][164]

Ngi ta cng thy r hn tc dng ca fluor khi gp hydroxyapatit ca rng

kt hp thnh fluoroapatit rn chc, chng c s phn hu ca acid to thnh

thng tn su rng. Bnh su rng ch din ra khi c 3 yu t cng tn ti (Vi

khu n, Glucid v Thi gian). V th c s ca vic ph ng chng bnh su rng l

ngn chn 1 hoc c 3 yu t xut hin cng l c [22], [73], [108]. C n mt yu t

th t kh ng k m ph n quan trng l bn thn ngi bnh. Cc yu t ch quan nh

tui tc, bt thng ca tuyn nc bt, bt thng b m sinh ca rng c th khin

cho kh nng mc bnh su rng tng cao v tc bnh tin trin nhanh. C ch

sinh bnh hc su rng c th hin bng hai qu tr nh hu khong v ti khong.

Nu qu tr nh hu khong ln hn qu tr nh ti khong th s gy su rng.

T m tt c ch su rng nh sau:

Su rng = Hu khong > Ti khong (c ch ho hc v vt l sinh hc)

S n nh ca cu tr c rng trong ming c cn bng bi hai qu tr nh hu

khong v ti khong xy ra trn b mt rng v trong m i trng nc bt quanh

rng theo thi gian th c. Khi nng pH ca nc bt quanh rng gim xung di

mc 5,5, tc hu khong nhanh hn tc ti khong.

Thc n

Rng

Vi khun

Thc

n

Cht

nn

Vi

khu n

D ng chy pH

quanh rng

Nc bt

http://www.ncbi.nlm.nih.gov/pubmed/?term=Usha%20C%5Bauth%5Dhttp://www.ncbi.nlm.nih.gov/pubmed/?term=R%20S%5Bauth%5D

13

iu ny c th hiu rng m i trng acid lm mt cu tr c men hoc ng

rng trn mt vng no ca thn rng m c ng thi c 3 yu t to ra acid:

Vi khu n, Carbonhydrat v Thi gian th c [79], [118]. Vic s dng cc ch ph m

sinh hc lm gia tng qu tr nh ti khong gi p iu tr su rng giai on sm

[72]. Cc yu t ch nh tham gia vo s cn bng hu khong v ti khong l:

- Vi khu n c sn trong ming, ch yu l lactobacillus v streptococcus mutans,

khi c thc n d nh ln mt rng c bit l ng v tinh bt, cc vi khu n s phn

hy thc n to nn acid n m n men rng to thnh l su. Vi khu n, acid, mn

thc n trn mt rng s to thnh mt mng d nh vo rng gi l mng bm rng,

mng ny rt d nh v c tt c cc mt rng c bit l rng hm [110].

Tc hu khong l c ny xy ra vt xa kh nng ti khong trn b mt

men ca m i trng nc bt quanh rng. Kt qu l to ra mt l su trn vng

thn rng , khi u l mt vng men rng m phn trng nhng d n d n s

pht trin tng d n k ch thc v chuyn thnh mt xoang trng trn thn rng c

mu nu hoc en. Sau khi men rng b n m n thnh l, vi khu n v thc n cng c

iu kin bm vo, acid cng c to ra nhiu hn, t chc cng (men v ng) cng b

ph hy, l su c m rng v tin v ph a ty rng. Nhng ngi b tt li h c v

chn rng th mng bm rng s bm ln v bt u qu tr nh phn hy thc n to acid

trn b mt c rng v chn rng, m cng ca rng b n m n to thnh l su [106].

C nhiu loi vi khu n sng trong m i trng ming (200 300 loi). Mt s

tr i ni t do trong ming, b y ra khi ming bi d ng chy ca nc bt v

thng b nut vo bng. Ch mt s sinh vt c bit nht l streptococci mi c

th bm vo cc b mt trong ming nh nim mc v cu tr c rng. Cc vi khu n

bm c nhng th th (receptor) c bit c th bm vo mt rng v n cng

to mt khung (matrix) d nh gi p cho ch ng bm vo vi nhau. S bm vo rng

v bm vo nhau gi p cho vi khu n t li trn mt rng [69], [151].

Mng bm vi khu n l nguyn nhn ch nh ca s ln men carbohydrates thc

n, ung tr thnh ion acid trn b mt rng. Hiu qu ca cht m nc bt

ca lng acid ny th t l nghch vi chiu dy mng bm [66], [110].

14

- Kh nng chng su ca rng c n ty thuc vo trng thi cng ca rng. Hm

rng kh ng b st m, kh ng khim khuyt, mc thng hng, men rng trng b ng,

mc khong h a rng cao l nhng yu t quan trng chng li cc tc nhn gy su

rng. Ngc li, cc yu t ny kh ng hon chnh th nguy c su rng l rt ln.

- Yu t tip theo gy ra su rng c nhc n nhiu l mng bm rng. Cc gn

thc n bm vo cc k rng, nu kh ng nh rng thng xuyn v kh ng ly cao

rng nh k s l m i trng thun li cho vi khu n gy su rng pht trin [91].

- Nhng yu t thc n bo v: Mt s th c ph m to thnh nhng yu t chng li

s mt khong. Chng hn, mng bm s gim mc tn c ng b mt rng vi s

hin din ca m. Nhng loi thc n i hi s nghin, nhai cc loi rau c x c

th coi nh l bo v, ko cao su lm gia tng lu lng nc bt cho nn c coi

nh c kh nng cht m. Cc loi tinh bt qua ch bin rt d bin i thnh

acid hu c d su rng. ng trong tri cy cng gy su rng nhng t v n s

lng kh ng ng k [124].

- Kh nng khng khu n, cn bng v gi cho pH > 5,5 ca nc bt cng l yu

t quan trng trong vic kim sot kh nng xy ra su rng v tc su rng [3],

[28], [48], [119]. Nc bt gi mt vai tr quan trng trong vic bo v rng chng

li s tn c ng ca acid. Lu lng nc bt v s lm sch ming nh hng trong

vic ly i cc mnh vn thc n v cc vi sinh vt. Tuy nhin, khi lu lng nc

bt mc cao cng c th ly i mt ph n lng fluor t trn rng, cho nn ta

c n tng s lng i hi mc ti a cho vic bo v rng [100], [156].

- Thi gian: Su rng ch pht trin khi phn ng sinh acid k o di v lp i lp

li. n thng xuyn cc cht carbohydrate ln men th d su rng hn tng lng

carbohydrate n trong 1 l n.

Nm 1995 Hi Nha khoa Hoa K a ra khi nim su rng l bnh nhim

trng vi vai tr gy bnh ca vi khu n v gii th ch nguyn nhn su rng bng s

vi ba v ng tr n ca cc yu t vt ch (rng: gm men rng, ng rng, xng

rng) m i trng (thc n c kh nng ln men cha carbohydrate) v tc nhn (vi

khu n ch yu l streptococcus mutans v lactobacillus) [121].

15

u th k 21, c nhiu quan im v su rng, su rng c bit l mt bnh

a yu t hay l bnh a phc hp, nh bnh ung th, bnh tim mch, bnh i tho

ng, trong , nhiu yu t nguy c thuc v gen, m i trng v hnh vi tng

tc vi nhau (h nh 1.3). T , ch ra hng nghin cu cho vic d ph ng v

iu tr su rng hiu qu hn [164].

Hnh 1.4. Lin quan gia cc yu t bnh cn-lp lng vi khun v rng v cc

thnh phn sinh hc (vng trn bn trong) v cc yu t hnh vi v kinh t -x hi

(vng trn ngoi) [Ngun: Usha C. and Sathyanarayanan R (2009)][164]

1.2.2. Dch t hc bnh su rng

1.2.2.1. T l bnh v ch s rng su mt trm

o lng mc bnh su rng, ngi ta dng t l % v ch s rng su

mt trm (SMTr), trong S l rng su, M l rng mt do su v T l rng trm,

SMTr l ch s ch p dng cho rng vnh vin v kh ng hon nguyn c ngha l

ch s ny mt ngi ch c tng ch kh ng c gim. SMTr t ng ngi c th

ghi t 0 n 32. i vi nghin cu dch t hc, SMTr ca cng ng l tng s

SMTr ca t ng c th chia cho s c th ca cng ng.

Thu nhp

Hnh vi

Gio dc

Thi

Kin thc

Thnh phn nc bt

Dng chy nc bt

Rng

Cn bm

VK

Cn bm VK

Rng

Rng

Fluor

Thc n

Vi khun

Kh nng m

Cht ng

Tng lp x hi

http://www.ncbi.nlm.nih.gov/pubmed/?term=Usha%20C%5Bauth%5Dhttp://www.ncbi.nlm.nih.gov/pubmed/?term=R%20S%5Bauth%5D

16

i vi rng sa, khi p dng ch s ny s c k hiu bng ch thng

smtr, trong s l rng su, m l rng mt do su v t l rng trm. i vi rng

nh tr em, rt kh phn bit rng nh do su hay rng sa rng sinh l c su

hay khng. ci tin, dng smtr dng cho tr trc tui thay rng hay ch dng

cho rng ci sa, hoc su (s) s dng cho rng sa, trong khng k n rng

mt hay rng nh [9].

Ch s ny c gi tr ln trong gim st su rng trn ton c u, c T chc

Y T Th gii (TCYTTG) cng nhn v a vo h thng nh gi su rng nm

1997 [176]. Nm 2005, TCYTTG c ng nhn v a vo s dng h thng nh gi

ICDAS, h thng ny vn s dng cc ch s trn, tuy nhin, khi ghi nhn su rng

theo h thng mi, cho ph p ghi nhn li nhng tn thng su rng giai on

sm (vt trng) cha to l su, nhng tn thng su rng ny c th hon nguyn

bng cc bin php ti khong h a [9].

- Hn ch ca ch s SMTr: mc d u ch s SMTr c s dng trong nh gi t nh

h nh su rng theo TCYTTG, n c th cung cp d liu dch t hc v su rng,

nhng cng tn ti mt s hn ch.

Th nht, cc nh nghin cu ghi nhn mt s lng ng k sai lch khi

nh gi, th hai, n kh ng cung cp bt k ch dn v s rng c nguy c hoc cc

d liu lin quan v iu ny l hu ch trong c t nh nhu c u iu tr; ch s SMTr

kh ng t nh rng b mt v l do khc vi su rng (nh bnh nha chu) v cng

kh ng t nh n rng c trm hoc c phc hi th m m m kh ng c vo

nhng nm 1930 khi phng php ny c a ra [119]. Trn th gii, so snh

quc t v gim st xu hng ca bnh su rng, ngi ta t nh ch s SMTr la

tui 12 (s rng su mt trm trung b nh mt ngi) theo cc mc [171].

Bng 1.1. Phn chia mc lu hnh bnh su rng ca TCYTTG [175]

Mc SMTr 12 tui

Rt thp

17

1.2.2.2. Dch t hc bnh su rng trn th gii

Theo TCYTTG, t sau Chin tranh th gii l n th hai n 1975, tnh hnh

su rng cc nc pht trin ngy cng cao. Ch s SMTr t 7,4 n 12. Tuy

nhin, n cc nm t 1979-1982 th ch s ny gim xung cn t 1,7 n 4.

Ngc li, cc nc ang pht trin th sau Chin tranh th gii l n th hai, t l

su rng thp, n nhng nm 1980 li tng cao [169]. T 1983 n 2002, nhiu

nghin cu cho thy su rng tr t bin ng v c xu hng gim xung. Mt

iu tra ca c quan Gim st Dinh dng v Sc khe Hoa K trong cc nm

1988-1994 v 1999-2002 cho thy la tui 6-12 ch s SMTr l 1,62 v 1,67 [76].

G. Davies v cs (2013) ghi nhn ti Anh, c gim t l tr em b su rng t

30,9% nm 2008 c n 27,9% vo nm 2012, tng ng vi ph n trm thay i l

9,7%. Ch s SMTr gim t 1,11 nm 2008 c n 0,94 nm 2012, gim 15,3% [90].

Trong khi cc nc ang pht trin, th t l su rng li c khuynh

hng gia tng, ch s SMTr t 1960 n 1972 l 0,1 n 6,5 nhng t 1976 n

1982 tng ln t 2,3 n 10,7. T 1983 n nay, nhiu cng trnh khoa hc cng b

vi t l su rng khc nhau nhng u mc cao [124].

Alamoudi N, Salako NO, Massoud I. (1996) nghin cu su rng ca 1522

tr em t 6-9 tui ti Jeddah, A Rp X t. Kt qu cho thy trung b nh SMTr rng

sa v rng vnh vin theo th t l 4,23 v 1,85. C mt t l cao su rng kh ng

c iu tr v h u ht cc rng b su c nh b. T cho thy t m quan

trng ca cc bin php ph ng ng a [61].

Bajomo AS v cs (2004), nghin cu su rng tr 6 tui, 12 v 15 tui Nam

Phi ghi nhn c s tng gp i trung b nh SMTr t 12 tui n 15 tui v mc su

rng cho tt c cc nhm tui cao hn so vi mc trung bnh [71].

Cleaton-Jones P, Fatti P, Bnecker M. (2006), nh gi t nh tr m trng v

t n sut su rng cc nc ang pht trin qua 35 nm (1974-2004) tr 5-6 tui

v 11-13 tui. T l su rng thp nht Nam Sahara Chu phi, cao nht Chu

M La tinh v Caribe. T l su rng gia tng cc nc ang pht trin [85].

mt s nc trong khu v c: theo th ng bo ca TCYTTG nm 1994 v nm

1997, h u ht cc nc trong khu v c c trn 90% dn s b su rng v ch s SMTr

http://www.ncbi.nlm.nih.gov/pubmed?term=%22Alamoudi%20N%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Salako%20NO%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Massoud%20I%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Bajomo%20AS%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Cleaton-Jones%20P%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22Fatti%20P%22%5BAuthor%5Dhttp://www.ncbi.nlm.nih.gov/pubmed?term=%22B%C3%B6necker%20M%22%5BAuthor%5D

18

tui 12 nhiu nc c n mc cao, t 0,7 (Trung quc) n 4,9 (Campuchia) [136].

Cho n g n y, Datta P, Datta PP (2013), nghin cu t n sut su rng hc sinh

bang Sundarban, n l 71%, cao tr thuc gia nh c thu nhp thp [89].

u th k 21, bnh su rng vn cn l mt vn sc khe rng ming

(SKRM) h u ht cc nc cng nghip ha, nh hng n 60-90% hc sinh v

a s ngi ln. N cng l mt bnh v RM ph bin nht mt s nc chu

v M Latinh, trong khi li t ph bin hn v t nghim trng trong h u ht cc

nc chu Phi [172]. Nam Phi, nghin cu 30.876 tr 5-12 tui 9 vng cho thy

tnh trng su rng c gim vi ch s SMTr t 2,2 nm 1989 c n 1,1 nm 2002, tuy

nhin trn 80 % tr em c su rng cha c iu tr [71]. Do s thay i iu kin

sng, t l su rng tng cc nc ang pht trin chu Phi t nhng nm 1970

n 2004, c bit do tng tiu th cc loi ng v ngun fluor kh ng [85].

Theo TCYTTG (2005), 90% thanh thiu nin c vn v SKRM. M, ni

su rng l thp hn so vi cc ni khc, thi gian i khm v cc vn RM khin

117 000 gi hc b mt trn 100 000 tr em. Vn v RM khin cho au khi nhai

nh hng n tiu th cc cht x v mt s th c ph m giu cht dinh dng; do

, nng beta carotene, folate v vitamin C thp hn ng k nhng ngi c

t nh trng RM k m hn [173], cht lng cuc sng gim lin quan n SKRM

kh ng tt [168]. T n sut su rng cao c n lin quan n hon cnh kinh t-x hi

nh tr thuc dn tc t ngi, gia nh ngho, nhp c [81].

Cc nghin cu dch t hc g n y u ghi nhn th c trng bo ng ca

SKRM ton c u, nh hng n tr em cng nh ngi ln, rng sa cng nh rng

vnh vin. iu ny i hi s cp bch ca chin lc y t c ng cng m rt

thnh c ng trong qu kh, mt chin dch mi cho fluor di mi h nh thc,

chng tr nh gio dc SKRM trng hc, dng ch nha khoa, ch n ung

th ch hp v khm rng nh k [70].

1.2.2.3. Dch t hc bnh su rng ti Vit Nam

T nm 1960 n 1990 c nhiu tc gi c ng b kt qu iu tra su rng ti

nhiu a phng, cho thy su rng lu hnh ph bin nc ta [50].

19

V Th Quang v cs (1990), iu tra c bn SKRM Vit Nam, ghi nhn, t

l su rng tui 12 l 55,69%, SMTr l 1,852,32 [36]. Nm 1998, Nguyn L

Thanh c ng b kt qu kho st bnh RM ca hc sinh tiu hc t 8-11 tui ti

huyn Gia Lng, tnh Bc Ninh t l su rng sa l 54,4%, su rng vnh vin l

5,9%, bnh quanh rng l 83,8% [40]. o Th Ngc Lan v cs (1999), iu tra

hc sinh tiu hc tnh Yn Bi cho thy su rng sa l 41,79% [26].

Vin Rng Hm Mt H Ni phi hp vi Vin nghin cu v thng k

SKRM Australia tin hnh iu tra bnh RM Vit Nam trong 3 nm 1999-2001

thu c cc kt qu: 6-8 tui c 84,9% su rng sa, 25,4% su rng vnh vin

(smtr: 5,4; SMTr: 0,48), 9-11 tui l 56,3% v 54,6% (smtr: 1,96; SMTr: 1,19) [53].

Theo Nguyn C n v cs (2000), t l bnh su rng v ch s trung b nh

SMTr gia tng theo tui. SMTr tr 12 tui v la tui 35 44 l 1,2 v 1,3 cc

tnh thnh ph a Bc v 2,9 v 8,2 cc tnh thnh ph a Nam. Mc tr m trng

su rng min Nam cao gp 2 l n min Bc cc nh m tui [4].

Trong khi , theo Trnh nh Hi (2000) cc vng Duyn hi Trung b cho

thy t l su rng sa tr t 6-8 tui kh cao, t 83,7% - 91,6%. T l su rng

vnh vin tr gia tng theo nh m tui [16].

Trnh nh Hi (2005), nh gi th c trng su rng cho thy, t l su rng

sa rt cao 73,2% tr 6 tui, 72,3% tr 6-8 tui, 53,2% tr 9-11 tui. Ch s

smtr l n lt l 2,49; 3,45; 1,69 [ 17].

Nguyn Ngc Ngha (2009), nghin cu trn 400 hc sinh tiu hc ti 2 trng

Ngha L v Nm B ng ca huyn Vn Chn, tnh Yn Bi nm 2009 ghi nhn, t

l su rng l 62,75%, ch s SMTr trung b nh trn mt hc sinh i vi rng sa l

2,68, i vi rng vnh vin l 0,37 [29].

V Mnh Tun, Tr n Vn Trng (2011), cho thy t l su rng vnh vin

ca hc sinh Trng Tiu hc ng Ngc A, H Ni l 57,1% [54].

Nghin cu ca Vn c (2011) ti th trn Thun Nam, tnh B nh Thun

cho thy t l su rng hc sinh tiu hc l 65,23%, trong vng ven c t l su

rng l 80,48% [ 56]. Trng Mnh Dng v cs (2011) nghin cu ct ngang 7.775

tr 4-8 tui ti 5 tnh thnh Vit Nam ghi nhn 81,4 % su rng sa (smtr l 4,7),

20

16,3% su rng vnh vin (SMTr l 0,3), 90,6% c cn bm, 81,1% c cao rng,

11,9% chy mu li [7].

Nghin cu ca V Th nh (2012) cho thy t l bnh rng ming ca hc

sinh tiu hc H Ni l 59,78%, smtr v SMTr l 1,77 v 0,127; T l rng su c

bin chng l 35,4%, t l hc sinh c khm v iu tr thp [13].

Ti tnh Long An, t l su rng hc sinh tiu hc trong nghin cu ca Tr n

Ngc ip l 78,7% [12].

Theo V Vn Thanh (2013), t l su rng chung hc sinh tiu hc Huyn

Ty Sn Tnh B nh nh nm 2011 l 78,8%, trong su rng sa 93,7% v su

rng vnh vin chim 28,3% [ 42].

Kho st ca i hc Y H Ni trn hn 2.000 hc sinh 6-8 tui H Ni v

Lng Sn, i din cho hai khu v c min n i v th Vit Nam, c c ng b

ti Hi ngh khoa hc v o to Rng Hm Mt l n th 4 t chc H Ni t ngy

26 n 28-11-2013. Theo kt qu kho st, t l su rng chung ca hc sinh l trn

91%, trong hc sinh ti Lng Sn c t l su rng sa 93%, su rng vnh vin

l 10,1%, hc sinh cng tui ti H Ni c t l su rng sa trn 87%, su rng

vnh vin ln n 19,3%.

Ti tnh Th a Thin Hu, mt s c ng tr nh nghin cu v SKRM cho thy t

l su rng vn c n cao. Tr n Tn Ti (2007), nghin cu la tui hc sinh ph

th ng trung hc cho thy t l su rng l 70,7% [39].

Hong Anh o, Nguyn Toi (2008), nghin cu hc sinh trung hc c s

ng bng v min n i tnh Th a Thin Hu ghi nhn, t l su rng ng bng

la tui 12: 40,38% v SMTr 1,07 v la tui 15: 70,93% v SMTr 1,89 [11].

Nguyn Toi v cs (2011), nghin cu t nh h nh bnh rng ming ca nhn

dn thnh ph Hu, ghi nhn, t l su rng theo la tui 12, 15, 35- 44 l 54,3%;

60,0%; 65,2% v ch s SMTr theo th t l 1,33; 1,98; 3,41 [49].

G n y, theo nghin cu ca Tr n Vn Dng (2012), t l su rng chung ca

nhn dn thnh ph Hu l 84,1%, t l su rng tng d n theo tui 12, 15, 35- 44,

65-74 l 74%, 81%, 86%, 95,5% v ch s SMTr trung bnh l 3,66 [6].

21

1.2.3. Cc yu t nguy c gy su rng

Ngy nay vi s tin b ca khoa hc, ngi ta bit rng su rng chu nh

hng ca nhiu yu t lin quan vi nhau: c t nh sinh hc, hon cnh x hi,

hnh vi, tm l v mc sng ca i tng. Cng ngy, cng c nhiu yu t nguy

c c bit lin quan n su rng [73], [80], [103].

Tuy nhin t kinh nghim lm sng ca nha s v s hin din s lng v

tr m trng ca su rng ngi ta nh gi c nhng yu t nguy c su rng

ni tri gm: vi khu n, dinh dng, ngun nc, sc khng ca rng v nc

bt. S nh gi gi p cho vic ra chin lc iu tr tu thuc vo yu t ni tri

v ti u ho vic s dng fluor liu php [9], [31], [157].

C nhiu nguy c gy su rng trong c yu t fluor ca nc cng vi cc

yu t sinh hc, x hi, hnh vi v tm l c nhn mnh nhiu hn c [1], [135],

[148], [171].

Theo Cleaton-Jones P (2011), 98% nhng nguy c ch yu gy su rng tr

em l do n ung thiu fluor, v sinh rng ming (VSRM) k m v n cht ngt

(ng) m kh ng kim sot c [85].

Vi nghin cu nhng nguy c gy au rng tr em c 2 thp k qua, cho

thy t nh trng su rng ph thuc vo tui v iu kin sng. Nhng th nghim

nh gi nguy c su rng c th c nh gi bng d on, nhng du hiu lm

sng v tin s l du hiu quan trng nh gi nguyn nhn ch nh ca su rng

trong mt c nhn. Thi ca cha m v SKRM, tr em b o ph , tin s su rng

nht l rng hm vnh vin th nht tr thnh yu t tin on tt nht cho su rng

tr em [64], [101].

Nghin cu ca Al-Mutawa SA v cs (2006) vi 4.588 tr t 5-14 tui

Kuwaiti, nguy c su rng l VSRM k m v gia tng theo tui [65].

C n thit mt nghin cu dc theo vng nh gi nhng yu t nguy c c

xc nh theo yu c u c th kh ng phi nm trong nh m c t l bnh thp. nh

gi bt c nguy c no cng i ti c bin php th ch hp ph ng bnh.

nh gi nguy c su rng tr em l mt ph n trong vic nh gi sc kho

ton thn, c bit l tin s s dng fluor, thi quen VSRM [59], [171], [174].

http://www.ncbi.nlm.nih.gov/pubmed?term=%22Cleaton-Jones%20P%22%5BAuthor%5D

22

1.3. HU QU CA BNH SU RNG

Su rng c TCYTTG xem l mt trong ba mi nguy cho sc khe con

ngi sau bnh tim mch v ung th, hu qu ca su rng c mi lin quan cht

ch vi cc vn v SKRM v kinh t x hi.

1.3.1. V sc khe rng ming

Khi l su mi hnh thnh h u nh kh ng gy kh chu cho ngi bnh nn t

ngi pht hin ra. Khi xut hin nhng tn thng c th nhn thy bng mt

thng th a ph n cc bnh nhn thng than phin v vic dt thc n v nhng

cn au nhc khin h n ng khng ngon. T su ng kh ng iu tr, bnh su

rng s tin trin n ty gy vim ty cp, sau ty s b hoi t d n a n

vim ty mn ri n ty cht, thi. Nhng cht hoi t ca ty c th thot qua l

ch p chn rng gy nn nhng bnh l vng quanh chp, vim t chc lin kt,

vim xng hm..., hoc t li chn rng to nn u ht, nang chn rng... Ngoi

ra, vi khu n c th gy nhng bin chng xa nh vim xoang hm, vim ni tm

mc (Osler)...[48], [152].

c bit i vi tr nh, bnh su rng li c nhng tc ng tiu c c khng

ch trong mt thi gian ngn m c n k o di n khi tr trng thnh.

Chnh nhng l hng ban u xut hin trn b mt rng s khin tr c cm

gic but mi khi n phi cc n n ng lnh hay chua ngt. Sau khi tr khng

c n n na th cm gic ny s ht, v th tr d c suy ngh mun b ba trnh

cn au. Bn cnh , nu kh ng c iu tr sm, cc l su s ln d n v su

vo tn bung ty. Lc ny, cm gic au rng s xut hin vi mt dy hn

khin tr s chn n dn n st cn. Tnh trng ny ko di s lm tr suy nhc,

ri lon cm sc, lo u, gim sc khng do thiu cht dinh dng, c th dn n

suy dinh dng [28], [160].

1.3.2. V kinh t x hi

Ngi b bnh su rng thng lo lng v hi th c mi kh chu ca m nh

gy ra nhng kh khn trong giao tip t nh hng ti cht lng cuc sng v

23

c ng vic. Bn cnh , ngi bnh phi tn mt khong chi phi kh ln cho vic

iu tr su rng, nht l khi c bin chng vim ty.

i vi tr, bnh su rng khin tr tr nn th ng, ngi tip sc vi bn b,

hc hnh cng gim s t. Theo thi gian, tr s d c lp bn thn vi mi ngi

kh ng ch bn b xung quanh m c n c gia nh. iu ny rt nh hng n s

nh h nh tm l sau ny ca tr [28], [160].

1.4. VAI TR CA FLUOR TRONG NHA KHOA

Fluor l thnh ph n quan trng ca s ton vn m xng v m rng. Cc m

n y gi n 99% tng tng fluor trong c th. Khi s dng fluor vi hm lng

th ch hp trong nc, thc n, kem nh rng, nc s c ming v cc sn ph m

chuyn dng trong nha khoa c tc dng sau:

- Tng s khong h a m rng v c m xng (Chc nng khong h a m

xng cng c vai tr quan trng vi sc kho m xng).

- Gim nguy c v ph ng ng a su rng.

- Tng s ti khong h a m rng.

Fluor l cht duy nht c kh nng lm men rng cng chc t b h a tan bi

axit do vi khu n to ra, do fluor c tc dng ng a su rng. Fluor ngm vo men

rng bin apatit l cht v c ca men rng thnh fluoroapatit c tc dng:

- Tng cng cng chc gim kh nng h a tan ca men.

- Gi p ti khong h a sang thng su rng.

- Thu hp cc h r nh trn mt nhai ca rng.

- Hn ch s sinh acid v ngn chn vi khu n ln men do fluor c ch qu tr nh

chuyn h a ng ca vi khu n.

- Lm gim h nh thnh mng bm rng gi p ph ng bnh su rng v vim nha chu.

- Fluor dit vi khu n su rng c bit pH thp (pH < 5,5), c trong th c ph m

nh c, tr, bia... tc dng tt trn b mt lng ca men rng v c th s dng di

nhiu h nh thc [60], [142].

Nm 1984 TCYTTG a ra cc bin php d ph ng su rng v vim

quanh rng nh sau :

24

- D ph ng su rng: fluor ho nc ung, a fluor vo mui, s c ming bng

dung dch fluor cho tr em, dng kem nh rng c fluor, trm b t h r nh rng, ch

n d ph ng, hng dn v sinh rng ming, pht hin sm v iu tr d ph ng.

- D ph ng bnh quanh rng: lm sch mng bm rng l bin php can thip

ph ng chng bnh quanh rng. nh rng l vic lm quan trng lm sch mng

bm rng [169].

Vi bin php d ph ng su rng bng fluor l lm tng sc khng ca rng

nh fluor. Ngi ta ng l vic s dng rng r i cc dng fluor lm gim su

rng r rt M v nhiu quc gia khc. Fluor ho nc ung cng ng gi vai tr

quan trng do hiu qu lm sng v kinh t ca n . Cc cht b sung trong ch

n v fluor ho nc ung trong trng hc l cc h nh thc s dng fluor nhng

ni fluor ho nc ung kh ng th c hin c. Fluor ho mui n ang tr nn ph

bin hn mt s nc nh M, cc nc Ty u [83], [94], [142].

Hin nay fluor c c ng nhn l c hiu qu i vi mi la tui v ngy

cng tr nn quan trng trong cng ng [37], [38]. Hn hai thp nin qua, t l

ton b v t l mc mi bnh su rng gim cc nc pht trin, ph n ln l do

s dng fluor rng r i [155].

Song song vi t l su rng gim l t l rng nhim fluor tng. Cc nghin

cu v nhim fluor th c hin trong nhng vng c v khng c fluor ho, nhn

dng c 4 yu t nguy c ch nh gy nhim fluor l: s dng nc ung c fluor,

vin fluor, kem nh rng c fluor, v sa ng hp c fluor trc 8 tui [43], [45].

Fluor v canxi l hai yu t kin to nn men rng. Khi ung, fluor s np vo

cu tr c rng ang h nh thnh trong b dy xng hm cha mc; sau khi rng

mc fluor cng c th nh hng "t bn ngoi" vo lp men rng.

T nm 2011, vi s gi p ca TCYTTG, chng tr nh d ph ng su rng

cho nhn dn huyn Bt Xt (Lo Cai) bng s dng mui trn fluor c trin

khai. Ngoi Vit Nam, Lo v Nepal cng p dng a fluor vo mui n cho

cng ng. Trong thng 6 nm 2012, Bnh vin Rng Hm Mt TW H Ni a

20 tn mui trn fluor t l 250ppm vo s dng ti cng ng. u nm 2013 cng

tip tc a 40 tn mui fluor vo s dng ti 2 x khc ca huyn Bt Xt.

25

Ngy 16/4/2013 ti UBND huyn Bt Xt, Bnh vin Rng Hm Mt TW H

Ni cng S Y t tnh Lo Cai, UBND huyn Bt Xt, BVK tnh Lo Cai, Trung

tm Y t d ph ng tnh Lo Cai, Trung tm Y t huyn Bt Xt t chc L s kt

D n mui fluor. Qua bui hp nh gi hiu qu bc u ca D n phc

v li ch ngi dn 2 x Bn Qua v Bn Vc. a phng cng kin ngh c

tip tc D n kh ng ch trong thi gian 2011-2015 m c sau khi kt th c D n.

1.5. CC BIN PHP CAN THIP TRONG CNG NG D PHNG

SU RNG

1.5.1. C s khoa hc hnh vi ca truyn thng gio dc sc khe ti cng ng

1.5.1.1. Hnh vi sc khe: L nhng hnh vi ca con ngi c nh hng tt hoc

xu n sc khe ca ch nh bn thn h, ca nhng ngi xung quanh v ca cng

ng. Hnh vi l mt phc hp ca nhiu hnh ng chu nh hng bi nhng yu

t nh di truyn, m i trng kinh t - x hi v ch nh tr. Hnh vi sc khe th hin

nh sau [3], [5]:

- V kin thc: Kin thc hay hiu bit ca mi ngi c t ch ly d n qua

qu tr nh hc tp v kinh nghim thu c t cuc s ng. Hiu bit nhiu khi kh ng

tng ng vi kin thc m ch ng ta c th tip thu th ng qua nhng th ng tin m

th y c gio, cha m, bn b, sch v, bo ch cung cp. Hiu bit rt kh thay i

khi hiu bit l sai v tr thnh nh kin.

V nhng kin thc nha khoa ca hc sinh, c bit l hc sinh tiu hc, l

cc em c n qu nh c nhng kinh nghim. Do s quan st cng c n hn ch nn

tc ng n tr em nhiu nht ch nh l cm gic kh ng b nh thng i vi vn

rng ming. au rng l cm gic u tin m cc em gp phi. au kh ng n c,

kh ng ng c, kh ng chi c m phi hc v cc em u bit l v rng v

nh vy cc em c nhng nhn bit nht nh.

Kin thc c n ph thuc vo tr nh hc vn. Hc sinh lp mt kh ng th

hiu bit bng hc sinh lp nm. Ngay trong cng tui, cng lp hc, s hiu

bit v t ng lnh v c, t ng vn cng khc nhau Trong tui hc sinh, khi m

26

kin thc vn ho c n hn ch, kin thc v bnh RM cng hn ch theo, do

mun bit s hiu bit ca cc em n mc no, c n c s phng vn v quan

st. hc sinh tiu hc c nhng kin thc c n thit v bnh RM th cn c vo s

hiu bit, tr nh ca cc em v c n c nhng phng php truyn t th ch hp,

khi , vn gio dc nha khoa (GDNK) mi c hiu qu.

- V nim tin: Nim tin c sc mnh, nh hng n thi v hnh vi ca con

ngi. Nim tin thng kh thay i. C nhng nim tin ng v c nhng nim tin

sai. Do , c n lp k hoch truyn th ng gio dc sc khe (GDSK) thay i hnh

vi lin quan n nim tin cho ph hp. Chng hn, c n phi gio dc hc sinh c

nim tin l su rng kh ng phi c con su gy ra v tin rng c th cha khi c

su rng hoc bit cch ph ng s kh ng b cc bnh RM.

- V thi : L t duy, lp trng, quan im ca i tng i vi mt vn

. i vi hc sinh t duy lp trng v quan im c n nhiu hn ch ca s hiu

bit do la tui, iu kin kinh t - x hi, m i trng gio dc. Tuy nhin, ch nh s

tc ng ca nhng kin thc s khai v nht l tc ng ca au rng s h nh thnh

nn mt cch t duy v bnh RM t i tng c th c thi kh ng th

vi bnh ny mi khi n xut hin. T ch kh ng th , tin trin theo thi gian, la

tui, tr nh hiu bit v bin xut hin bnh, i tng s h nh thnh nn quan

im phi loi tr bnh.

- V th c hnh: Xut pht t nhng hiu bit, c kin thc s dn n nhng

hnh ng ca i tng. Kin thc v thi ng s dn n th c hnh ng v

ngc li. hc sinh tiu hc, nhng kin thc v thi v bnh rng ming s

c biu hin qua hnh ng ph ng chng n . ng nhin, kin thc v thi

mc thp th hnh ng cng mc tng ng.

Hnh vi sc kho c n c cc yu t khc nh: k nng l biu l kh nng lm

tt hoc x l mt vic g nh ti nng b m sinh, qua o to hoc th c hnh [3],

[83]. K nng chi rng ng phng php c n phi c th c hnh ti trng v

lp li trmg ngy ti nh di s hng dn ca cn b y t hc ng, s nhc

nh ca ph huynh. Tt nhin, nu trmg ngy u chi rng nhng chi rng ng

th c n phi c vai tr ca cn b Nha hc ng (NH).

27

1.5.1.2. Vai tr ca truyn thng gio dc sc khe trong thay i hnh vi

Gio dc sc khe cng ging nh gio dc chung, l qu tr nh tc ng

nhm thay i kin thc, thi v th c hnh ca con ngi. GDSK cung cp cc

kin thc mi lm cho i tng c gio dc hiu bit r hn cc vn sc

khe bnh tt, t h c th nhn ra cc vn sc khe bnh tt lin quan n

bn thn, gia nh, cng ng ni h ang sinh sng, dn n thay i tch c c gii

quyt cc vn bnh tt sc khe [169].

Truyn thng GDSK l ni dung u tin trong tm ni dung chm s c sc

kho ban u m Hi ngh Alma - Am ra nm 1978 v cng l ni dung u

tin trong 10 ni dung chm s c sc kho ban u ca Vit Nam, l: GDSK

nhm gip cho mi ngi c kin thc ti thiu v c bn nht h c th t

phng bnh cho m nh, cho gia nh, ngi thn v cho x hi; h c th x tr

ng khi b m au, bnh tt v h thay i nhng cch ngh v np sng c hi

cho sc kho. Vi vai tr quan trng nh th, trong cc hot ng chm s c sc

kho nhn dn nht l ti tuyn y t c s, cng tc truyn thng GDSK c xp

vo Chu n 1, Chu n quc gia v y t theo Quyt nh s 370/2002/Q-BYT ca

B Y t. Y t c s c iu kin g n dn, st dn, l tuyn u trong phng chng

dch bnh nn vic cng c cc hot ng truyn thng GDSK ti tuyn y t c s

c ngha ln trong c ng tc chm s c v bo v sc khe nhn dn.

Truyn th ng thng gm ba ph n chnh: ni dung, hnh thc v mc tiu.

Ni dung truyn thng bao gm cc hnh ng trnh by kinh nghim, hiu

bit, a ra li khuyn hay mnh lnh, cu hi.

Hnh thc th hin nh ng tc, bi pht biu, bi vit, hay bn tin truyn hnh.

Mc tiu c th l c nhn khc hay t chc khc, thm ch l ch nh ngi/t

chc gi i th ng tin [3].

1.5.2. Chin lc d phng bnh su rng

1.5.2.1. D phng da trn bnh sinh

T hn 50 nm nay vn d ph ng su rng c t ra, bi nu su

rng pht trin t nhin, sau mi iu tr, th kh ng mt quc gia no p ng

28

c v chi ph qu ln v nhn l c, my m c thit b, thuc, vt liu, tin v thi

gian vt cht cho qu tr nh iu tr. C nhiu quc gia tin hnh d ph ng su

rng, lm gim t l su rng t trn 90% xung ch c n 50 - 60% v gim c cng

su rng nh M, c, Ph n Lan, an Mch...[161]. D a vo cc hiu bit v cn

nguyn su rng, ngi ta tin hnh d ph ng theo 3 hng:

- D phng theo hng vi khun

Vaccin su rng c nghin cu v iu ch t vi khu n streptococcus

mutans cht, dng trn ng vt th nghim (chut). Ngi ta thy chut gim

su rng xung 60%. Vaccin ny k ch th ch h nh thnh cc Immunoglobulin A nc

bt (IgA) c kh nng c ch cc enzym glucosyltransferaza, do c ch s h nh

thnh dextran v mng bm rng. IgA ngn cn 90 - 99% cc vi khu n bm vo

men rng, nh lm gim t l su rng [84]. Tuy vy vaccin c n gy nhng phn

ng ch o vi cc t chc tim, thn, c ca chut, hn na vi khu n su rng

ngi phc tp hn chut. l nhng tr ngi c n gii quyt.

Trong khi ch c mt vaccin an ton c s dng, ch ng ta c n lm tt c ng

tc tuyn truyn VSRM rng r i trong cng ng [169].

- D phng theo hng gim n ng

Gim n ng hoc n ng xong phi sc ming. C th, l kh ng n

ngt gia cc ba n. Kh ng n m n ngt v m. Kh ng dng m n ngt lm m n

trng ming sau cng. T m cch thay th cc loi ng gy su rng bng ng

kh ng su rng [161].

- D phng su rng bng cch lm tng sc khng ca men rng

Fluor l nguyn t vi lng c tc dng tt nht cho men rng. Men rng h nh

thnh trong iu kin dinh dng fluor s l fluoro apatit, cht ny lm cho men

rng bn vng hn v kh ng b hu khong trong m i trng acid.

Fluor c n c tc d ng c ch cc enzym cho nn c tc dng chng li s h nh

thnh mng bm, ng thi chng li s h nh thnh acid gy su rng t cc cht

ng. Fluor c th lm tng nhanh tc ti khong ho men rng [60], [106].

29

1.5.3. Cc bin php can thip ca T chc Y t Th gii

TCYTTG a ra cc bin php ph ng bnh su rng nh sau [170]:

1.5.3.1. S dng fluor

- Fluor ha ngun cung cp nc c ng cng, t 0,7 n 1,2 mgF/l t nc.

- a fluor vo mui n vi 250 mg F/ kg mui, mui fluor kh ng th ch hp

nhng ni c hm lng fluor trong nc cao.

- S dng vin fluor nhng ni kh ng c fluor trong ngun nc cung cp, c th

s dng cho tr t 6 thng cho n 13-15 tui.

- S c ming vi dung dch fluor pha lo ng: sc ming hng ngy vi dung dch

fluor 0,05% hoc mi tu n 1 l n vi dung dch fluor 0,2%.

- Dng kem nh rng c fluor, dng gel fluor: Tng t cc loi thuc, vitamin,

dng fluor cho tr vt chu n cng gy tc hi. Trc 8 tui, thi im rng tr

ang pht trin, nu dng nhiu c th gy hin tng men rng b fluor h a, rng

i mu hoc thng xuyn c m. Mt s tr c cung cp fluor hng ngy

nhng hp th fluor t cc ngun khc cng gy nguy c nh trn [21], [45].

1.5.3.2. Trm bt h rnh

Trng hp mt rng c h r nh, c bit l mt nhai rng sau, l nhng ni

su rng thng xut hin. Tuy nhin, ngay c khi chi rng, dng ch nha khoa,

thuc s c ming k cng, th rt kh -nhiu khi l kh ng th- lm sch nhng h

r nh su v nh, l nhng ni rt d ng thc n. Nh vy, khc phc t nh trng

ny, c n trm b t h r nh bng Sealant [134].

1.5.3.3. Ch n hp l

Kim sot thc n v ung c ng bao gm: kim sot cc th c ph m

c ng trng hc, gim s l n n cc th c ph m c ng, ch n ng di

500gr/ngi/thng s gim ng k nguy c su rng.

S dng cht ngt thay th ng loi ngt m v xylitol kh ng gy su

rng. Thuc dng cho tr em vi cc cht ngt thay th ng s gim t l su

http://benhvienthammy.com.vn/chuyen-de-nha-khoa/benh-sau-rang.htmlhttp://benhvienthammy.com.vn/

30

rng cho tr. Kh ng nn cho tr ung nc hoa qu bng b nh v s k o di thi

gian rng tip xc vi ng v acid t hoa qu, kh ng ung nc ngt c ga [154].

1.5.3.4. Hng dn v sinh rng ming

V sinh rng ming ng cch rt quan trng trong kim sot v d ph ng

su rng.

- Chi rng: la tui tiu hc, tr c th t m nh c m bn chi chi rng, tuy

nhin, tr cc lp nh cha c k nng chi rng hiu qu lm sch rng, tr vn

c n s gi p , gim st, nhc nh ca b m. Kh ng phi l c no tr nh cng

thc c t m quan trng ca vic CSRM. Do , b m, ch nh l ngi th c hnh

ng VSRM tr noi theo, xem chi rng l c ng vic hng ngy phi lm. Chi

rng theo phng php Bass ci tin:

+ L a chn bn chi: S dng bn chi dng cho tr em, thay bn chi mi

theo nh k 3 thng 1 l n hoc khi l ng bn chi b x cng.

+ S l n chi rng: Mt ngy nn chi rng t nht hai l n (sau khi n sng v

trc khi i ng). Tt nht l chi rng 3 l n sau cc ba n sng, tra, ti.

+ i vi mt ngoi, mt trong: nghing bn chi 45 v ph a li rng, chi

vi ng tc rung nh ti ch nhiu l n ( l ng bn chi len su vo k rng,

massage nu tit dch nu). Tip , xoay bn chi l ng bn chi chy dc

theo chiu ca rng (chiu trn di) mi vng lp li t 6-10 l n.

+ i vi mt nhai: Chi theo ng tc ti lui ngn

Nn chi theo th t nhm trnh b s t rng v mt rng. Chi hm trn trc

hm di sau, mi hm c n chi sch mt ngoi, mt trong, mt nhai. Chi c n thn

mi l n 2-3 rng; tu n t cho sch tt c cc rng [111], [139].

+ Kem nh rng: chn loi c cng thc kh ng ng, c fluor chng su

rng. C n to cho tr cm gic ho hng vi vic nh rng, vi cc loi kem nh

rng c mi v khc nhau (to, cam, du, nho) hoc vi bn chi vi mu sc khc

nhau gip tr c nhiu chn l a.

- Lm sch k rng: Dng ch t nha khoa, c n tp cho tr em c th i quen dng ch

t nha khoa cng sm cng tt. Nu tr kh ng t dng ch lm sch rng c,

31

cha m nn lm thay cho tr. c bit cc rng ci sa thng kh t nn vic dng

ch t nha khoa lm sch thc n vng ny v mt xa rng ci trong cng l rt

c n thit. Ch t nha khoa th ch hp v tt phi l loi ch d s dng, kh ng gy

chn thng ln li rng [68], [87].

- Cc bin php khc:

+ S dng nc fluor v cc dung dch s c ming khc, kh ng th dng nc s c

ming thay kem nh rng. t hiu qu, nht thit phi nh rng trc khi s

dng nc s c ming.

+ Kh ng n hay ung ngay sau khi dng nc s c ming. Tt hn nn i 30

ph t sau khi s dng nc s c ming h y n hay ung.

- Dinh dng cn bng hp l v cht.

- Khm nh k kp thi iu tr cc bnh l rng ming.

- Tuyn truyn ph ng bnh: cho tr v cho b m, nhng ngi tr c tip chm s c

cho tr [169], [172].

1.5.4. Chng trnh Nha hc ng ti Vit Nam

1.5.4.1. Chc nng v nhim v ca chng trnh nha hc ng

Th ng t lin B Y t v B Gio dc v o to s 23/1987 ngy 21 thng 10

nm 1987 qui nh nhim v, t chc th c hin chng tr nh nha hc ng

(NH). Ngnh Y t chu trch nhim ch tr v c ng tc o to v ch o chuyn

m n k thut. Ngnh Gio dc chu trch nhim ch tr t chc th c hin. Gm 3

nhim v ch nh:

- C ng tc gio dc nha khoa (GDNK) l nhim v hng u trong c ng tc ph ng

bnh RM cho hc sinh ti trng hc, a gio dc SKRM vo chng tr nh ch nh

kho mi nm 4 tit cc trng tiu hc.

Gio dc SKRM l mt bin php m mi ngi c hng ng u ng

u qua bo ch , truyn thanh, truyn h nh... kh ng phn bit t ng lp x hi, kinh

t, vn ho... y l mt bin php d ph ng ch ng, nn c n c thi gian

ngi dn c th thay i tp qun c, ng thi trc khi gio dc c n phi ch

n tp qun, phong tc, t n ngng c th lm cn tr vic t b th i quen c hoc

32

chp nhn mt th i quen mi, kh nng kinh t, kh nng nhn thc, kh nng p

ng y t i vi cng ng.

Nhng bin php hng ti lm sch khoang ming c bit l rng, li rng,

bao gm chi rng v s c ming k sau khi n, dng ch nha khoa.

Chi rng v s c ming sau khi n l mt c ng vic ht sc nh nhng m hu

ch, l mt bin php hu hiu nht, d lm, r tin nht gi g n VSRM phng

bnh su rng v nha chu.

- Ph ng bnh bng fluor: Vin Rng Hm Mt chu trch nhim xc nh nhng a

phng c n cho hc sinh s c ming hng tu n bng dung dch Nafluor 0,2%. Nh

trng chu trch nhim t chc cho hc sinh s c ming fluor cng cn b NH.

- Kim tra nh k t nh h nh bnh RM hc sinh v c k hoch iu tr sm ti

trng trnh bin chng [25], [27], [50].

1.5.4.2. Cc gii php can thip trong chng trnh nha hc ng

- Ni dung I: Gio dc chm s c rng ming.

- Ni dung II: S c ming fluor 0,2% mt tu n mt l n.

- Ni dung III: Khm RM nh k pht hin sm bnh RM, th ng bo cho ph

huynh hc sinh hoc chuyn ln tuyn trn.

- Ni dung IV: iu tr d ph ng bin chng, trm b t h r nh rng vnh vin.

Trong qu tr nh t chc th c hin c n l a chn u tin l ni dung I v II.

Trong bn ni dung trn th ni dung I v II l c n thit v kh thi v :

+ H u ht tr em u n trng v c nhu c u ln trong chm s c RM.

+ Chng tr nh c th bao ph trn din rng, kh ng d ng m h nh mu.

+ Cn b chuyn khoa Rng Hm Mt cng nh cn b y t hc ng kh ng

c tt c cc trng.

+ Gio vin c th tr c tip tham gia chng tr nh ti trng.

+ Phng php v quy tr nh th c hin n gin.

Trong hai ni dung I v II: c n c bit y mnh chng tr nh chi rng v

y l ni dung d ph ng mang li hiu qu r nht trong vic ci thin t nh trng

v sinh rng ming ca hc sinh.

33

Mt s quc gia trn th gii cng l a chn cc ni dung u tin, th t u

tin t ng ni dung do t ng a phng d a vo hon cnh c th quyt nh.

V th c hin ni dung III v IV: c n phi tin hnh song song hai ni dung

ny vi ni dung I v II nhng vi t nh h nh nhn l c khan him nn vic gii quyt

u tin vn t ln trc. C ngha l khi chng tr nh ph ng bnh bao ph a s

cc trng, h u ht hc sinh c d ph ng, mi ngh n xy d ng ni dung

III v IV vi chin lc hnh ng c th.

1.5.4.3. Thc t chm sc sc khe rng ming ti Vit Nam

Ti Th a Thin - Hu, cng vi 63 tnh thnh trong c nc, chng tr nh Nha

hc ng c trin khai t nhiu nm nay. Tuy nhin, cng nh cc tnh

thnh khc ca Vit Nam, tr mc bnh su rng vn cao, t l cc bnh RM trong

ton dn ngy cng gia tng [17], [18], [25].

Th c trng ny t ra vn l phi chng cch t chc, th c hin ca chng

tr nh cha ph hp hay v thc ca ngi dn cha cao? Ngoi ra cc yu t nh

hng n bnh v d ph ng bnh RM ca hc sinh ph thuc rt nhiu vo s hiu

bit, cc bin php gio dc ca b m, nh trng vi hc sinh, cc phong tc, tp qun

v th i quen n ung, VSRM ca cc em, do vy yu t nguy c v hiu qu ca cc

bin php can thip c th thay i, din bin khc nhau theo cc vng, min khc nhau.

Th c t cho thy, hin nay chng tr nh NH mt s ni mi ch d ng li

hai ni dung u tin: GDNK v dy hc sinh c thc chm s c SKRM. D nhiu

trng hc c phng nha hoc nm trong phng y t nhng ngng hot ng do

thiu kinh ph, thiu nhn l c, thiu trang thit b. Ngoi ni dung khm rng nh

k c lng gh p vo chng tr nh khm sc khe u nm hc, cn cc ni dung

khc ca c ng tc NH cha c th c hin mt cch thng xuyn, lin tc.

Bn cnh , mt s ph huynh cha c thc phng bnh RM cho con, cn

c quan nim rng sa khng quan trng. Khi tr b su rng, s n rng hay mt rng

sm do chn thng th rng sa khc hoc rng vnh vin s di chuyn vo v tr

mt rng, lm rng vnh vin bn di kh ng c ch mc, gy ra rng ng m,

mc kt hoc rng chen ch c. y l cng l yu t thun li gy su rng. Nu tnh

trng su rng hay s n rng kh ng c iu tr s gy au nhc lm cho tr khng

34

n c, t dn ti bing n, thiu cht nh hng n s pht trin ca tr. V

v lu di, s gy ra nhng d tt, nh hng n th m m v sc khe ton c th.

Hin nay, t nh chung v t nh trng su rng ca tr em trn c nc, t l bnh

RM tr em Vit Nam c xp vo loi cao nht th gii. tr 4-8 tui ti 5 tnh

thnh Vit Nam c n 81,4 % su rng sa (smtr l 4,7), 16,3% su rng vnh vin

(SMTr l 0,3), 90,6% c cn bm, 81,1% c cao rng, 11,9% chy mu li [7].

iu c bit l s tr mc bnh RM li cao hn khu v c thnh ph, th,

vn c cho l nhm tr c gio dc VSRM tt hn, nhng li l khu v c s

dng nhiu thc n ngt nh bnh ko cc loi, ng [22], [31], [32].

Vi th c trng su rng tr em ang mc bo ng, t nm 2014, B Y t

quyt nh s tip tc y mnh trin khai chng tr nh NH.

1.6. CC NGHIN CU LIN QUAN TRONG VIC PHNG CHNG

BNH SU RNG TRONG NC V QUC T

1.6.1. Ti Vit Nam

Ti Th a Thin Hu, ngay t khi chng tr nh NH trin khai (1986),

Nguyn Vn Phn, Nguyn Th c Qunh Hoa (1991) tin hnh nh gi chng

tr nh NH trong 4 nm hc, t 1986-1990, ti Trng cp I, II Nguyn Ch Diu.

y l mt trong nhng trng c chm s c rng theo 4 ni dung ca chng

tr nh NH, kt qu ghi nhn: t l su rng tng d n hc sinh tiu hc qua 4 nm

(66,89%, 77,28%, 81,89% v 83,59%), SMTr la tui 12 qua 4 nm (0,88, 1,64,

1,43 v 1,50) [34] .

T l su rng gia tng qua 4 nm chng t c ng tc NH cha lm tt,

hc sinh cha hp tc (th d trong bui s c ming NaF cc em v a s c v a nghch,

kh ng t theo yu c u), th y c gio cha nghim t c a bi ging GDNK vo

chng tr nh dy ca m nh. l nhn nh ca nh m nghin cu. V vy, thc,

t nh t gic ca hc sinh cng nh s hp tc ca th y c gio l cc vn then

cht cho s thnh c ng ca chng tr nh.

Hong Trng Hng (1997), nh gi hiu qu ca chng tr nh NH, c

th l chi rng v GDNK hc sinh khi 5 ca mt s huyn ca 3 tnh (Vnh

35

Long, B nh thun, Long An), kt qu cho thy, ch s mng bm ci thin r so vi

trc chng tr nh c ngha thng k, qua , nh m tc gi ghi nhn, s c ming

fluor n thu n m kh ng kt hp vi chi rng ng s kh ng ly sch c mng

bm rng, ch gim 30% su rng trn mt lng nu c duy tr 36 l n/nm v kh

to cho tr mt k c h nh thnh th i quen tt trong vic gi g n VSRM [20].

Nghin cu chng minh vai tr ca chi rng ng cch, vi gio dc

SKRM ti trng kt hp vi tng cng nhc nh chi rng ti nh. Vic nhc nh

thng xuyn s gi p tr h nh thnh th i quen tt trong chm s c rng ming.

Trnh nh Hi v cs (2000) iu tra th c trng su rng, bnh quanh rng

v VSRM hc sinh cc trng tnh Hi Dng trc khi can thip chng tr nh

NH, tip , nh gi hiu qu ca chng tr nh v ph ng chng su rng v bnh

quanh rng cc trng hc qua 8 nm (nin kh a 1989-1990 n 1997-1998),

ghi nhn: t nh trng cc bnh RM hc sinh kh ng c chm s c NH l rt

nghim trng, t l su rng c xu hng gia tng; vic can thip bng cc bin

php CSRM l tui hc ng c hiu qu tt trong ph ng chng su rng v bnh

quanh rng, c th lm gim t l su rng, ch s SMTr, kim ch tc gia tng

su rng theo tui v ci thin t nh trng VSRM tr em [16].

Ti thnh ph H Ch Minh, Trnh Minh Th v cs (2001) nh gi hiu

qu ca chng tr nh NH 1343 hc sinh trng tiu hc inh Tin Hong sau 5

nm (nin kh a 1995-1996 n 1999-2000) ghi nhn, t l su rng sa 67%, smtr

3,15 (nm 1990 l 84,41%, smtr 8,0), su rng vnh vin lp 4 l 15,5%, SMTr

0,2. Tuy nhin c t l nhim fluor mc bo ng hc sinh 9 tui. Qua , tc

gi nhn x t NH em li hiu qu thit th c cho vic chm s c SKRM hc

sinh. Bn cnh tc gi t cu hi, vic s c ming bng nc fluor c c n

thit na kh ng? Sau khi tm ngng fluor c th p dng mt s bin php fluor ti

ch i vi nhng i tng c nguy c su rng cao [47].

Nghin cu ny cho thy cc cch thc d ph ng bnh RM cng phi ph

hp vi t nh h nh SKRM hc sinh, ph hp vi a phng nghin cu nhm gim

t l su rng nhng kh ng gy tc hi trn s h nh thnh men rng v phng din

th m m.

36

Tng kt 10 nm vi chng tr nh NH ti Qun 3, thnh ph H Ch Minh,

Lm Hu c v cs (2001) iu tra 14 trng tiu hc gm 11.953 hc sinh, kt

qu: tr 6 tui, su rng sa 63,14%, smtr 4,55; su rng vnh vin 4,8%, SMTr

0,128; tr 12 tui su rng sa 21,33%, smtr 0,35; su rng vnh vin 40,66%,

SMTr 0,66. Hiu qu chng tr nh NH ch c c t ni dung I v II; mc

nhim fluor trn rng la tui 12 l ng k [15]. Nh vy, ni dung III v IV cha

c hiu qu, l t nh h nh chung hin nay trn c nc, hot ng ti cc ph ng nha

c nh cng gp nhiu kh khn. D c 90% trng c ph ng nha hoc nm trong

ph ng y t nhng nhiu trng, ph ng nha ngng hot ng. Nguyn nhn ch nh

l thiu kinh ph , thiu nhn l c. Ngho nn v trang thit b l kh ph bin trong

NH v chng tr nh ph ng ng a su rng cho tr kh ng t kt qu cao.

Dng Th Truyn (2004) nh gi hiu qu cc bin php CSRM trong

ph ng bnh su rng ti cc trng tiu hc v trung hc c s th x Long Xuyn,

tnh An Giang. Tc gi tin hnh nghin cu can thip i xng gm 4 nh m hc

sinh 6 tui v 12 tui (mi nh m 240 em): nh m chng s c ming vi dung dch

fluor (gii php ph cp t 1984), nh m 2 s c ming fluor + hun luyn chi rng,

nh m 3 s c ming fluor + trm su rng bng GIC, nh m 4 s c ming fluor + hun

luyn chi rng + trm su rng bng GIC. Khm xc nh t nh trng su rng trc

v sau can thip sau 2 nm. Kt qu cho thy: gim t l su rng r rt, rng sa

nh m 2 gim 5,2%; nh m 3 gim 9,5%; nh m 4 gim 20,55%, nh m chng li tng

14,22%. h rng vnh vin, nh m 2 gim 4,69%; nh m 3 gim 3,09%; nh m 4

gim 4,96%, nh m chng tng 10,17% [52].

Nghin cu trn tp trung can thip theo 3 ni dung ch nh: gio dc nha

khoa, s c ming vi fluor v trm rng. V vy, kt qu cho thy gim t l su

rng. y l cc ni dung trong chng tr nh NH c n duy tr thng xuyn cc

trng hc.

Nh vy, trong nhiu nm qua, chng tr nh NH c trin khai n

h u ht cc tnh trong c nc, mt s ni thu c kt qu kh quan. Ti thnh

ph H Ch Minh, nc my c fluor ho, ng thi c ng tc NH cng c

x hi ho, ch nh nh vy, t l bnh RM ca hc sinh gim ng k (hc sinh

37

12 tui vng c fluor ho nc t l su rng l 77,0% nm 1990 gim xung

67,3% nm 2003) [37], [38].

Cc nghin cu v hiu qu chng tr nh NH ca mt s tc gi mt s

a phng cng cho thy kt qu tt [15], [16], [46]. Nhng cng c nhiu ni hot

ng NH cha ng v cha ph hp nn chng tr nh CSRM cha n c tt

c hc sinh v vy kt qu cha c nh mong mun.

Bn cnh , nghin cu ca Trng Mnh Dng v cs (2011) 5 tnh thnh

ca Vit Nam cho thy c n 81,6% tr 4-8 tui b su rng sa, smtr l 4,7; su

rng vnh vin l 16,3%, SMTr l 0,3; 90,6% c cn bm, 81,1% c cao rng, trn

95% tr c s mt cn bng su rng; kin thc, thi , th c hnh ca hc sinh v

cha m cc em v ph ng chng bnh rng ming c n thp [7].

Ti Th a Thin - Hu, cng vi 63 tnh thnh trong c nc, chng tr nh

NH c trin khai t nhiu nm nay. Tuy nhin, cng nh cc tnh thnh

khc ca Vit Nam, tr mc bnh su rng vn cao, t l cc bnh v rng ming

trong ton dn ngy cng gia tng [6], [11], [39], [49].

1.6.2. Ti nc ngoi

Ngay t 1986, C.Stecksn-Blicks v cs nghin cu ct ngang v th c trng

su rng v theo di dc 817 tr 4 tui, 8 tui v 13 tui 3 vng ca Thy in.

Kt qu cho thy t l su rng khc nhau cc vng, iu ny c gii thch do

s khc nhau trong GDNK, s l n chi rng v s dng fluor. Kt qu nghin cu

dc ghi nhn, t n sut su rng cao tr tiu th ng nhiu, n nhiu ba trong

ngy, c bit rt cao tr c t l cao lactobacilli v S. mutans trong nc bt,

lin quan lng ng tiu th cao [155].

Bnh su rng l mt bnh a nguyn nhn, trong vi khu n ng vai tr

quan trng. Ngoi ra cn phi c cc yu t thun li nh ch n ung nhiu

ng, VSRM khng tt to iu kin cho su rng pht trin. V vy, vai tr

ca GDNK trong phng chng su rng d a trn bnh sinh su rng, l yu t quan

trng lm gim t l su rng.

38

P.E. Petersen v cs (2004), vi s gi p ca TCYTTG tin hnh nghin

cu theo chng tr nh gio dc SKRM (OHE) ca TCYTTG bao gm gio dc thay

i hnh vi 3 trng tiu hc v 3 trng nhm chng thnh ph V Hn, Trung

Quc, theo di trong 3 nm. D liu v su rng, chy mu li v hnh vi i vi

SKRM c thu thp. i tng bao gm 803 tr em v m ca tr, 369 gio vin

tiu hc. Sau 3 nm (7/1998 n 10/2001), kt qu ghi nhn: chng tr nh c tc

ng tch c c v gim chy mu nu, hnh vi SKRM ca tr em, v kin thc, thi

ca ngi m v gio vin v SKRM. Tuy nhin, khng c tc dng tch c c i

vi t l mc bnh su rng [136]. iu ny cho thy, gim t l su rng i hi

s phi hp cc phng php ph ng chng bnh RM theo TCYTTG.

Jackson RJ v cs (2005), nghin cu trn 517 tr em (tui trung bnh 5,63

nm), Anh v x Wales, so snh vi nhm chng khng can thip. Gio vin lp

hc c o to cng mt k thut nh rng th ch hp cho tr nh. Tr em trong

nhm can thip chi mt l n/ngy trng. Hc sinh nh rng c gio vin gim

st vi kem nh rng c cha 1450 ppm fluoride. Kt qu cho thy, i vi tr em

nhm can thip, su rng tng chung (2,60) l t hn ng k (10,9%; p

39

nh kt hp fluor vi kem nh rng c fluoride, s tng hiu qu phng su rng

hn. Cc bng chng cha khng nh hiu qu ca cht phng thch fluor

chm v sa c cht fluor [122].

Bedwani NR v cs (2008), th c hin chng tr nh d phng v GDNK cho

480 tr t 6-12 tui Alexandria, Ai Cp, theo m h nh c th c hin Php,

thi gian 1 nm (2008-2009). Chng tr nh nhn mnh vai tr ca gio dc SKRM

qua tranh nh, t ri, truyn thng...Kt qu: gim t l su rng tr, dn n cc

li ch v kinh t x hi, li ch v SKRM cho tr v gia nh [75].

Nh vy, nghin cu ch yu tp trung vn GDNK, iu ny cn c cc

gii hn: mt s tr khng hp tc, mt s tr kh khn khi gio dc (tr thuc gia

nh t ng lp thp trong x hi), phng tin gio dc cha (kem, bn chi

nh rng...). Mc d u vy, nghin cu cho thy li ch ca GDNK thng qua

cc phng tin truyn thng.

Cooper AM v cs (2013), tng kt cc nghin cu nh gi hiu qu lm sng

ca cc can thip d a vo trng hc nhm thay i hnh vi lin quan n thi quen

nh rng v t n sut tiu th th c ph m, ung gy su rng tr em (4-12 tui)

phng ng a su rng. C bn nghin cu bao gm 2.302 tr em. Ch c mt

nghin cu bo co kt qu ban u ca s pht trin ca su rng. Ba nghin cu

bo co c gim ch s mng bm c ngha nhm can thip. Trong , hai

nghin cu c s tham gia ca cha m lin quan n chng tr nh sc khe rng

ming (tr chi v bi tp v nh) th c hin vi con ci ca h. Mt nghin cu

bo co rng can thip c mt tc ng tch c c vo kin thc SKRM ca tr em.

Kt lun ca cc tc gi: kh ng c bng chng v hiu qu ca cc can thip

hnh vi d a vo trng hc gim t l su rng. C bng chng hn ch v hiu

qu ca cc bin php can thip d a trn kt qu mng bm v trn s t c v

kin thc SKRM ca tr. Khng nghin cu no s dng bin php can thip d a

trn hoc c ngun gc t l thuyt hnh vi [86].

Nh vy, c n cc nghin cu cht lng cao s dng l thuyt trong vic

thit k v nh gi cc bin php can thip nhm thay i hnh vi SKRM tr em

v cha m ca tr.

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Ti Thi Lan, P.E. Petersen v cs (2015) th c hin nghin cu ko di hai

nm, nh gi li ch ca chng tr nh chm s c SKRM tng cng, kt hp

chi rng c gim st ti trng, s dng kem nh rng c cha 1450 ppm fluor v

1,5% arginine, i vi SKRM v su rng. Nghin cu th c hin 15 trng pha

Nam Thi Lan vi 3.706 tr; trong 8 trng hc vi 1.766 tr em l nhm

chng; 7 trng vi 1.940 tr em nhm can thip. Trong s cc trng can thip,

5 trng c phn loi l trng c hp tc v hai trng l khng hp tc, d a

trn tiu ch c 80% tham gia vo cc hot ng nh rng theo quy nh. Kt qu:

SMTr v SMTm (men rng v ng rng) l 1,19 v 1,91 cho cc nh m chng;

1,04 v 1,59 cho nhm can thip. Cc nhm ny gim 12,6% v 16,8% tng ng.

SMTr v SMTm ("ngng ng rng") l 0,26 v 0,44 cho nh m chng, 0,19 v 0,29

cho nhm can thip, chim 26,9%, v 34,1% gim t l su rng tng ng. i vi

cc trng hp tc nhiu th li ch ln hn: gim n 40,9% su rng cho SMTm

("ngng ng rng"). thi im kim tra li sau 24 thng, c nhng ci tin ng

k v ch s mng bm rng, c bit ci tin ln trong nhm can thip, cn ln hn

na trng c hp tc tt [139].

Nghin cu ny vi ni dung d ng hai vn l GDNK v s c ming vi

fluor cng cho kt qu tt. Do , mt s quc gia trn th gii cng l a chn

cc ni dung u tin, th t u tin t ng ni dung do t ng a phng d a vo hon

cnh c th quyt nh.

T kt qu cc nghin cu can thip trong v ngoi nc nu trn, ch ng t i

xut v th nghim mt m h nh lng gh p nhiu loi thit k trong mt

nghin cu sc khe cng ng. Vic th c hin cc gii php can thip t nghin

cu phn t ch cho ph p kim nh gi thuyt v mi quan h nhn qu gia mt s

yu t nguy c vi bnh su rng, t xut cc gii php can thip th ch hp

vi cc gi thuyt c kim nh.

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Chng 2

I TNG V PHNG PHP NGHIN CU

2.1. I TNG NGHIN CU

Hc sinh v cha m hc sinh ti mt s trng tiu hc thnh ph Hu v

huyn min n i Nam ng, tnh Th a Thin Hu.

2.2. THI GIAN NGHIN CU

Thi gian nghin cu t iu tra ban u n nh gi can thip: t 5/2013 n

5/2015:

- Giai on 1: Trin khai thu thp s liu trong iu tra ct ngang, t 2/2014 n

5/2014. Trong giai on ny ng thi th c hin nghin cu bnh-chng gh p cp

v nghin cu nh t nh.

- Giai on 2: Trin khai can thip, t 5/2014 n 4/2015.

- Giai on 3: nh gi can thip, t 4/2015 n 5/2015.

2.3. PHNG PHP NGHIN CU

2.3.1. Thit k nghin cu

Do mc tiu ch nh ca nghin cu ny l nh gi cc gii php can thip lm

sng v cng ng nhm d ph ng su rng ti pht v su rng mi trn hc sinh

(HS) ti mt s trng tiu hc Th a Thin Hu, nn nghin cu p dng thit

k nghin cu can thip c i chng. Tuy nhin, chn c cc gii php can

thip th ch hp nht cho giai on can thip, nghin cu p dng thit k nghin

cu bnh- chng gh p cp kt hp vi nghin cu nh t nh.

l a chn c HS b su rng v kh ng b su rng cho nghin cu bnh

chng gh p cp th nghin cu p dng mt iu tra ct ngang pht hin ra

HS b su rng v kh ng b su rng trong cc trng tiu hc c chn vo mu

nghin cu. Do vy thit k nghin cu ct ngang trong nghin cu ny c mc

ch ch nh l pht hin cc HS tiu hc b su rng, cc vn RM lin quan su

42

rng v HS khng mc bnh su rng phc v cho cc giai on nghin cu tip

theo ch kh ng c mc ch xc nh cc yu t nh hng t mu nghin cu

ngoi suy ra qu n th nh cc thit k trc y vn p dng.

Di y l s tr nh by mi lin quan gia 3 thit k nghin cu c phi

hp c nh lng v nh t nh v mc ch ca t ng loi thit k nghin cu ny:

S 2.1. Mi lin quan gia 3 thit k nghin cu v mc ch ca tng thit k

Vi cch thit k ny th ch nhng HS tiu hc c chn vo nghin cu

bnh chng gh p cp mi c n phi phng vn cc yu t nguy c. iu ny kh ng

ch lm gim khi lng c ng vic trong giai on nghin cu ct ngang m c n

tng gi tr khoa hc ca nghin cu do kt qu t nghin cu Bnh Chng cho

ph p kim nh c gi thuyt nghin cu, c n kt qu t nghin cu ct ngang

ch cho ph p h nh thnh c gi thuyt nghin cu m th i.

S v ph n din gii di y tr nh by chi tit cc bc trong 3 giai on

thit k nghin cu nu trn.

- Giai on 1: L thit k iu tra ct ngang nhm pht hin HS mc bnh su rng

v kh ng b su rng, t xc nh t l su rng ti cc trng c nghin cu

v chn i tng nghin cu vo nh m bnh v nh m kh ng bnh cho giai

on nghin cu tip theo.

- Giai on 2: L thit k nghin cu bnh chng ghp cp, kt hp vi nghin

cu nh tnh, trong nh m bnh c chn trong s nhng HS b su rng, c n

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nh m chng c chn trong s HS kh