C H U Y £ N Pg: HINH THAI HpC VA CONG NGHg THONG TIN
CAM NHAN CUA NGUAl TRONG VA NGOAI NGANH RANG HAM MAT VE MOT SO DAC DIEM THAM MY NU COAl: DlldNG GIlTA HAM THEN,
DO NGHIENG MAT PHANG NHAI VA OUANG 01/01
Tran Hai Phyng*, Dong Khic Tham*, Le Thanh Hiing*
T 6 M TAT
Muc tieu: so sanh cam nhan tham my nu cu'di cua bac si rSng ham mSt (BS RHM) va ngi/di ngoai nganh.
Boi tu'dng va phu'dng phap:
TLf anh mpt nu cudi ciia mot ngu'di nU, phan mem xu' ly hinh anh tao ra cac thay doi vie 60 lp nu'dUjdp 16 rSng ciia ham tren,du'dng giiJa cung rang va dp nghieng mat phang nhai. Cac hinh anh du'dc sap xep trong phan mem danh gia tham my nu cu'di, giao dien tu'dng tac cho phep ngu'di danh gia tu" thao tac de chon ra nu cu'di dep nhat va khoang chap nhan cua moi bien so.
Co 100 BS RHM va 100 ngu'di ngoai nganh tham gia khao sat.
Ket qua: Nu cu'di dep nhat theo danh gia cua BS RHM co moi tren vita chamco rang ciia giita cho den phu rang 0,5mm, trong khi ngu'di ngoai nganh thich phu rang tir 1 - l,5mm.Ca hai nhom chap nhan lp niTdu 1,5mm va phii rang cii^
giij^ 2 - 3,5mm.BS RHM chap nhan dudng giiia lech khoang 1mm, ngu'di ngoai nganh la 2,5mm.BS RHM chap nhan mat phang nhai nghieng 2,5° trong khi nhom ngu'di ngoai nganh la 3,5°.
Ket luan: BS RHM co phan khat khe hdn benh nhan khi chon khoang chap nhan ciia cac dac diem tham my nu cu'di, do vaycan lu\i tam den quan niem tham my ciia benh nhan khi tu' van va lap ke hoach dieu tn.
TCr khoa: Tham my nu cu'di, Dp lp nu'du, dp lp rang cita ham tren, di/dng giiJa rang so vdi mat, dp nghieng mat phang nhai.
* Khoa Rang Ham Mat - Dai hoc y du'oc TP. I-ICM Phan bien khoa hgc: PGS.TS. Ngo Thi Quynh Lan 58
SUMMARY
PERCEPTION OF DENTISTS AND LAYPERSONS TO SOME ELEMENTS OF THE SMILE ESTHETICS: MAXILLARY MIDLINE,
OCCLUSAL CANT AND SMILE-LINE.
Objective: Compare the perception of the smile esthetics between the dentists and laypersons.
Materials and methods: A digital image editing software altered smile characteristics (dental midline deviation, occlusal cant, gingival display and maxillary incisal display) in 3 photographof an female smile. The photos were arranged in a software, an interactive interface allowed raters to select the ideal for each smile characteristic presented and identify the range of acceptability for the variables. 100 dentists and 100 laypersons participated in this survey.
Results: The most attractive smile judged by dentists was the one where the upper lip rests on the gingival margin of the upper incisor or covers the upper incisor 0.5mm, while the laypersons considered 1-1.5mm upper lip incisor coverage as the most esthetics. Both groups accepted 1.5mm gingival exposure and 2-3.5mm upper lip incisor coverage. Dentist accepted 1mm midline deviation, while laypersons accepted 2.5mm. 2.5° occlusal cant was accepted by dentists, while 3.5° cant was accepted by laypersons.
Conclusion: Dentists were more critical than laypersons when evaluating the smile characteristics, therefore, patients'expectatioife
Y HQC VlgT NAM T H A N G 10 - SO B A C BlgT/2013 should be considered in treatment planning and
making recommendations.
Key words; Smile esthetics, smile-line, maxillary gingival display, maxillary Incisor display, maxillarymidline to face, occlusal cant, I. M d OAU
Ngay nay, khi muc song ngay cang dugc nang cao, benh nhan tim den cac djch vu nha khoa khong chi don thuan muon cai thien chu-c nang an nhai ma con rat chu trpng den khia canh thdm my. Co ve nhu BS RHM dong vai tro chu dao anh huong den quyet dinh va su lira chpn ciia benh nhan. Tuy nhien, khong phai luc nao dieu nay cung dung, bcri le, benh nhan con co quan diem tham m^ rieng ciia ban than va them vao do la hi chi ph6i bcri nhiing nguai xung quanh, ma doi khi benh nhan nghe theo y kien cua ngudi xung quanh hem la nghe Idi bac si*9'.
Vi vay, that la thieu sot khi chiing ta chi dua vao y kien chii quan khi xem xet va lap ke hoach dieu tri ma bo qua y kien ciia benh nhan vi co the hai y kien nay khong triing lap vdi nhau.
Nhieu nghien cihi tren the giai da so sanh cam nhan ve tham my nu cudi cua BS RHMva nhihig ngudi ngoai nganh'7'9"'^*.
Cac nghien cuu nay cho rang BS RHM, nha chuyen mon nen co phan khat khe hem benh nhan khi danh gia cac yeu to lien quan den tham my rang-nudu.
Quan diem tham my ciia moi ca nhan khac nhau tiiy kinh nghiem ca nhan va moi trudng xa hpi'4'. Do do, nSu chiing ta sir dung cac ket qua nghien ciiu da co tren the gidi de ap dung cho ngudi Viet thi co the khong phil hop. CJ Viet Nam, da co mot so cac cong trinh nghien ciiu ve nu cudi '2" ' '.
tuy nhiSn chua co nghien ciiu nao so sanh cam nhan tham my nu cudi cua BS RHM va
cdng chiing. Ben canh dd, cac nghien ciiu trudc day cung chua de cap den gid tri toi uu va khoang chap nhan cua nhOTig dac diem tham my rang nudu. Hien nay, quan diem
"benh nhan la trung tam" trong ch5m sdc siic khoe ndi chung va sire khde r&ng mieng noi rieng ngay cang phd bien. Quan diem nay giiip cho bdc sT luu lam den y kien va mong mudn ciia benh nhan khi lap ke hoach dieu tri. Nhdm giiip cho bdc sT chuyen khoa chinh hinh rang mdt, phuc hinh, nha chu, phdu thudt ndi rieng va BS RHM ndi chung biet duac cdc ddc diem dupe nhieu ngudi cho Id dep nhdt va khoang chap nhdn cua benh nhan khi danh gia mot so khia canh tham my nu cudi, chiing toi thuc hien nghien cuu ndy vdi muc tieu so sdnh cam nhdn tham my giu'a BS RHM vd ngudi ngoai ngdnh khi ddnh gid cac dac diem sau;dp lech dudng giita, dp nghieng mat phang nhai, mdc dp Id rang va nudu. Ben canh do, chiing toi cung so sanh cam nhan thdm my theo gidi tinh ciia ngudi ddnh gia.
II. 061 TUpNG VA PHUONG PHAP NGHIEN COU 2.1. Doi tu-gng nghien ciiu
Mau nghien curu gdm 2 nhdm:
100 BS RHM ngudi Viet, sinh sdng va hdnh nghe nha tai TP. HCM.
- 100 benh nhan va ngudi nhd tudi tir 18-55, Id ngudi Viet, sinh song d Viet Namden kham vd dieu tri tai cac khu dieu tri ciia khoa RHM.
Tieu chi loai trie ciia nhom ngodi ngdnh:
Da hodc dang dieu tri chinh nha Da hoac dang lam trong nganh RHM (trp thu nha khoa. ky thuat vien phuc hinh rang...)
Cd ngudi than trong ngdnh RHM NhiJng ngudi khdng hap tdc Nhihig ngudi khong du minh man 2.2. P h u v n g p h a p nghien ciru Thiet ke nghien ciru: Cat ngang mo td
59
CHUYfeN oi: HJNH THAI HpC VA C 6 N G N G H $ T H O N G TIN
ChQn ngudi mdu vd chyp dnh Chung toi khdm vd budc dau chpn Ipc mpt sd doi tupng n\i dp tuoi tir 18 d^n 40, tinh nguydn tham gia nghien ciiu va phii hpp vdi cac tieu chi ciia mpt r\\\ cudi d?p theo nghien ciiu ciia Nguyen Thu Thuy vd CS.
(2005'"*'. Sau do chung toi ticn hanh so sdnh vd hpi y vdi mpt so chuyen gia trong ngdnh de chpn lAn 2 ra ny cudi phii hpp nhat cho nghien ciiu:
Dudng gitJa rdng triing vdi dudng gi&a mdt
Mdt phdng nhai khdng bj nghieng trong mdt phdng trdn.
• Ti le cac rdng trudc ham tren phii hpp vdi ti le trung binh ciia ngudi Vi?t'^"'
Dudng cudi trung binh, khdng lp nudu Cung cudi song song
Dudng cong moi tren hudng len ho^
thdng
• Khi cudi, rdng trudc ham tren ch^m nh? hodc khong ch^m mdi dudi
: Cudi lp it nhat den m$t gdn rang c6i thii nhit ham tren
- Khdp cdn hai hda, cdc rang sap x^
deu d^n, khdng cd di hinh hay khiem khuyet, khdng bj mat rdng (trir rdng khdn).
- Mpt cay thudc do dupe ddt thdng diing, sdt ben phai cua mat doi tupng de Idm can cii dieu chinh cac hinh nu cudi ve kich thudc that khi tien hdnh khdo sat.
- Chup hai anh d mdt phdng tran: anh thii nhat chup nu cudi tu nhien d tang mat dudi va anh thir hai chup cung rang vdi dung cu banh mipng vdi diem ngdm Idy net la tilp diem ciia hai rdng ciia giiJa hdm tren.
Hinh I: Nu cudi tu nhien Hinh 2: Ham rSng nhin tir phia trudc vcSri dung cy banh mi?ng 2.3. PhiroTig p h a p xir ly h i n h a n h
Quy trinh xir ly dnh do Ackerman vd cs. dua ra ndm 2002. "'
Dung phan mem Adobe Photoshop dS cdt anh mgt thdng vdi nu cudi tu nhien chi dl thi}
tir dinh muidSn ranh mdi-cam, cdc rang va mo nha chu dupe xda di d^ tao khung mdi.
Xir ly dnh mdi va cung rdng cho ddi xiing qua dudng giira.
Chen cung rdng vdo khung mdi dk tao anh chudn.
Bdng 1: Tdm tat pham vi vd each xdc djnh cac bidn sd nghien ciru
06 lech du'dng giu'a rSng ham
tren
__Cach xac dinh Khoang each theo chieu ngang tir dudng giu'a hai rSng cira giij'a den du'dng thSng di qua giiJa moi tren va giij'a nhan trung.
Cach xiyiy anh Dl chuyen du'dng giOS hai rSng cita giiJa ham tren ma khong lam thay doi khoang toi hanh lang mieng.
khoang each gtiJa hai anh la 0,5mm.
Pham vi 10 anh lech phai:
-4,5mm ->0 10 anh lech trai:
0 ->+4,5mm
Y Hpc VIET NAM THANG 10 • S 6 D^C BI$T/2013
Do nghieng m^t phSng nhai
Dp 16 rSng va ni/du
Dp xoay oJa cung rSng tren va dutif trong mSt phSng tran vdi tam xoay nSm giOa hai rSng cii^ giuci.
Khoang each theo chiSu dpc t i i diem cao nhat ciia vien nu'du rSng ciTa giO^
ham tren den bd du'di moi tren ngay phi'a tren cac rSng nay.
Nghieng toan bp cung rSng, khocing each giij'a hai anh la 0,5°.
Dp lp r3ng cita: CS chuyen m6i tren xuong d u ^ va phii dan cac rSng eu^.
Oo lo nudu: Moi tren dUdc di chuyen len tren so vdi vien ni/du mSt ngoai fSng CLici giOa ham tren.
Van giu' nguyen tuUng quan giQa bd can r^ng tru6c so vdi m6i dudi Khoang rach giiia hai anh la 0,5mm.
10 anh ngu'dc chieu kim dong ho:
-4,5°->0°.
10 anh cLing chieu kim dong ho: 0°-»+4,5".
11 anh dp 16 rSng aia:
moi tren tu* phii rSng - 5mm giam d3n d§n 0 mm.
10 anh dp lp nUdu: til 0mm den +4,5mm.
2.4. Phirong phap thu thdp so lieu Thu thdp sd lieu nghien ciiu bang phan mem danh gia nu cudi chay true tiep tren mdy tinh. Phan mem nay do chiing tdi tao ra gdm cdc phdn sau:
Phdn 1: Thu thap thong tin cua ngudi ddnh gia: ten, tudi, gidi tinh, nghe nghiep.
Phdn 2: Khao sat y ki^n
Ddi tupng tham gia nghien ciiu se danh gia thdm my ciia nu cudi bang cdch trd Idi 3 cdu hdi idn:
1. Dd lech dudng giiia 2. Dp nghieng mat phdng nhai 3. Dp Id rdng va nudu
Mdi cau hdi Idn gdm 3 cdu hdi nhd: a, b, c.
Cdu hdi a diing de xdc dinh "Gidi ban tren":"7«' trdi sang phdi, vui long chon hinh ddu tien md anh chi thdy chdp nhgn duac".
Cau hdi b dimg de xdc nhdn "Gidi han dudi": "Tic trdi sang phdi, vui long chon hinh ddu tien md anh chi bdt ddu cdm thdyxdu".
Tiep theo, phan mem se ket noi hai loat hinh tir "Gidi han tren" din "Gidi han dudi"
de cho ra mdt loat hinh thii ba Id cdc hinh trong "Khoang chdp nhan".
Cau «- diing de xac nhdn "Gid tri tdi uu": "Trong cdc hinh sau day, anh/chi vui long chon hinh dep nhdt".
III. KET QUA
Trong nghien ciiu nay, chung tdi Idy y kien ddnh gid ciia 200 ddi tuong gdm 100 BS RHM vd 100 ngudi ngoai ngdnh tudi tir 18- 55. Cdc ddi tupng deu la ngudi Viet Nam, ddn tdc Kinh vdi ti le nam: nii trong mau nghien ciiu khd cdn bang.
Dp kien dinh ciia ngudi ddnh gia the hipn bang chi sd Kappa dat khd cao 0,61 (0,61 - 0,8) d mire y nghia p<0,05.
3.1. Do lech dirdtig giira
Cd su khac biet giira BS RHM va ngudi ngodi nganh d mire p<0,05. Trong khi cac BS RHM chi chap nhan dudng giGa lech trong khodng 1mm thi nhdm ngudi ngodi ngdnh chap nhan lech trong khoang 1,5 - 2,5mm.
CHUYSN 06: HINH THAI HQC VA CONC NGH6 TH6NG TIN
Hinh 3: Dutag giiJa l?ch I mm Hinh 4: Dirong gitta l?ch 2,5mm
3.2.B9 nghieng mat ph^ng nhai ^ Sir Ivra chcjn cua nliom BS chu yeu tap trung trong cac mijrc dp l?ch lu 0 den 2,5°, the hifn
bang ti 1$ chpn cao troi hon cac miic l$ch Ichac. Trong Ichi do, Ichoang chap nhan cua cac doi tupng trong nhom ngoai nganh rpng han. den Ichoang 3,5".
Trong ySu to nay, Ichoang chip n h ^ ciia nhom BS RHM va ngircti ngoai nganh khac biet CO y nghia thong Ice (p<0.01).
Hinh 5: Mat phang nhai nghieng 2,5" Hinh 6: MM phang nhai nghieng 3,5 3.3. Mirc do lo rang va niro'u
Gid trj t6i iru
Nhom BS RHM chpn nu cuoi dep nhat khi bo moi tren vua eham co rang cita giua cho den phu co rang cira giua 0,5mm, ti le chpn la 49%. So voi nhom ngiroi ngoai nganh, ti le lira chpn cua cac BS RHM kha nhat quan va tap trung nhieu nhat trong khoang nay.
Nhom ngoai nganh chpn nu cuoi dep nhat voi duong cuoi trong khoang phu rang ciia gitta tu 1 - 1,5mm, chiem ti le cao nhat 37%.
Sir khac nhau giua nhom BS RHM va nhom nguoi ngoai nganh co y nghTa th6ng ke voi p<0,01.
62
Y Hpc Vl|T NAM THANG 10 - s 6 DAC B 1 | T / 2 0 1 3
Hinh 7; Dp lp nudu = 0 Khoang chhp nhdn
Xet rieng ddc diem mdi phu rdng, nhdm ngodi nganh chpn miic chap nhdn tir 2- 3,5mm chiem 75%. trong khi dd chi cd khodng 36% cac BS RHM chap nhan miic nay. Mdt ti le gdn tuang duang (30%) cac BS RHM chi chap nhdn mdi phu rdng trong khoang 0 - 1,5mm.
Xet ve dp lp nudu, ti le cdc BS RHM chap nhan dp lp nudu 0-l,5mm cung chiem ti le cao nhdt (85%), tuy nhien, cac miic dp chap nhan cd ti le chpn cao chu yeu tiip trung
Hinh 8: Mdi phii rang 1,5mm trong mirc nay. Khi mirc dp Id nudu tir 2mm trd di, ti le chap nh^n cua cac BS RHM rdt thap (15%). Nhdm ngodi nganh cung chap nhdn dp 16 nudu 0-1,5mm chiem ti le cao nhai, nhung ti le nay nhd hon so vdi ti lp chpn ciia cdc BS RHM (62% so vdi 85%).
Ngoai ra, khoang 36% nhdm ngoai ngdnh chap nhdn lp nudu trong miic 2 - 3,5mm.
Su khac biet giua hai nhdm BS RHM va ngodi ngdnh cd y nghia thdng ke vdi p<0,001.
Hinh 9: Dp Id nudu 1,5mm Hinh 10: Mdi phu rdng 3,5mm 3.4. So sanh cam nh^n tham mp theo gidi
B^ l^ch dtrofng giira
So sanh khoang chdp nhan ciia dp lech dudng giiia theo gidi trong nhdm BS RHM vdi phep kiem Fisher cho thdy khdng cd su khac bi?t cd y nghia giira nam va nii. Ket qud cung tuong tu vdi nhdm ddi tupng khdng chuyen mdn (p>0,05).
Dp nghieng mat phang nhai So sdnh miic dp chdp nhdn dp nghieng mat phdng nhai theo gidi trong nhdm BS RHM vd nhdm ngudi ngoai nganh: ket qua cho thay mirc dp chdp nhan giiia nam va nii khdng khac biet cd y nghia thdng ke (p> 0,05).
Dp lp rdng vd nir&u Gid tri toi icu
Khi chpn lua dp lp rdng va nudu tdi uu.
63
CHUVeN BJ: HINH THAI HQC VA C 6 N G N G H £ T H O N G TIN
ket qud cho thay khdng co sg- khde bi?t cd y nghia giiia nam vd ni^ trong nhdm BS RHM vdi p>0,05.
So sdnh cdc kk qua theo gidi trong nhdm ngodi nganh cung cho ket qud tuang t\r, p>0,05.
Khodng chdp nhdn
Vh mirc dp mdi phii rdng, cdc BS nam chdp nhgn nhieu nhdt (46,3%) trong khodng tir 0-1,5mm cdn da so cac BS nii (43,5%) chdp nh^n mirc tir 2- 3,5mm va sy khde bi^t ndy cd y nghTa thdng ke (p> 0,05).
V^ dp lp nudu, khdng cd s\r khac bipt cd y nghTa thdng ke giii-a nam va nit (p>0,05).
Khoang chap nhdn cua dp lp rdng vd nudu theo gidi trong nhdm ngoai nganh khdng khac biet cd y nghTa thdng ke (p>0,05).
IV. BAN L U A N
4.1. Ve mau nghien cihi
Ve mau ngudi trong nganh RHM, chung toi chpn BS RHM vi day la ddi tupng true ti^p tu vdn, cd tdm anh hudng den quyet dinh ciia benh nhdn. Id ngudi true tiep dieu tri cho benh nhdn ddng thdi chiu trdch nhiem ve ket qua diku tn cung nhu su hai Idng ciia benh nhan. Vdi dp tudi trung binhla 33, udc tinh thdm nien cdng tac khoang 8 ndm, chua ke thdi gian hpc vd thuc tap trong trudng dai hpc. Day la khodng thdi gian tuy khong dai nhung cung dii de hinh thdnh nhan thuc ve tham my trong nha khoa.
Ve nhom mau ngodi ngdnh, chiing tdi loai tru nhihig ngudi dd hodc dang dieu tri chinh nha, bdn than hoac cd ngudi than lam trong nganh rdng hdm mat de trdnh khd nang cac ddi tuang nay qud chii y den thdm my rang mieng, se dnh hudng den tinh khdch quan trong nhan xet. Cdc tieu chi loai trir nay
cung dupe dp dyng trong nhilu nghien ciiu tuang tu tren the gidif'"-'"'"...
4.2. Ve phu-ong ph^p thu th^p dir lieu Phuang phdp diing ph4n mIm danh gia ny cudi Id mpt sy thay ddi so vdi phuong phap truyin thdng diing thang do VAS de djnh luong ddnh gid ve thdm my. Cd the noi, day la xu hudng chpn lya ciia cac nghien cim gan ddy tren thi gidi khi khao sdt gia tri tdi uu vd khoang chdp nhgn ciia cac ddc diem tham m^ ny cudi. Do do, chung tdi da sii dung phuang phap ndy trong thu thap sd li?u.
Phuang phap nay cho phep ngudi danh gid tu minh thao tac tren cdc biin sd de xem mdt ddy cac kha ndng, chpn dupfc chinh xdc hinh Iy tudng vd gidi han chdp nhdn thay \\
phai ddnh gia va hodc cho diem tren nhihig hinh da dupe chpn sdn. Vdi phuong phap nay, ngudi ddnh gia cd the so sdnh mpt so lupng hinh ldn mpt cdch nhanh chdng va cho phep lua chpn de dang. Dieu nay ldm cho thiit kl nghien ciiu hieu qua hon, do thong tin thu thdp dupe tir khdo sdt chinh xdc hon.
4.3. Do lech dirfmg giira
Ket qud nghien ciiu ciia chung tdi cho thdy BS RHM chdp nhdn khi dudng giiia lech 1mm va ngudi ngoai nganh van chap nhan khi dudng giiia l?ch den 2,5mm.
Khoang chap nhan ciia nhdm BS RHM trong nghien ciiu ndy gidng vdi khoang chap nhan cua cac BS CHRM trong nghien ciiu cua Pinho, nhung theo Pinho, cac BS chuyen khoa phyc hinh chap nhdn lech duong giira den 3mm va ngudi ngodi nganh khdng nhan thdy bit thudng cho dii dudng giiia lech 4mm^"'.
Ket qud cua chiing toi cho thay viec lech dudng giiia it ban 2,5mm khdng cd dnh hudng den cam nhan thdm my ciia cong chiing, mpt vdi tdc gia ciing cho ket qua tuong tu nhu Johnston va cs. (1999) • Cardash va cs. (2003) ^^\ Nghien cuu ciia 64
Y Hpc VigT NAM T H A N G 10 - s 6 BJ>C BlgT/2013
Ker (2008) cho ket qua khodng chdp nhdn Id 2,9mm^'°l Tuy nhien mdt sd nghien cuu khac cho thay khodng chap nhgn ciia cdng chung din 4mm Kokich va cs. (1999)'"', Pinho va cs. (2007)^"'.
4.4. D9 nghieng mat phdng nhai Trong nghiSn ciiu cua chiing tdi, gidi han chap nhgn ciia nhdm ngoai nganh Id 3,5"
trong khi nhdm BS RHM chap nhdn mdt phang nhai nghieng den 2,5°.
Cdc nghien ciiu ve dp nghieng mdt phang nhai khde cho thay cd nhieu ket qua khde nhau. Vdi ngudi ngoai ngdnh, y vdn ghi nhan cdc miic dp chap nhdn sau: 1° (Mc Leod, 2010^''"); 2" (Geron 2005'5'); 2,75°
(Springer, 2010''*') vd 4° (Padwa va cs., 1997"*'; Ker va cs., 2006^'*")
4.5. Dp lp rang va nirdli
Trong nghien ciiu cua chiing tdi, xet tren ca hai nhdm, khoang tdi uu ciia dudng cudi tir vira eham cd rang cira giiia den phii rang 0,5mm, trong khodng nay, dp Id nudu bang khdng dupe chpn nhilu nhdt. Nhdm BS RHM Cling thich nhdt vi tri dudng cudi nay.
Kokich vd cs. (1999) nghien ciiu tren dnh chup mdi vd rdng, Dutra va cs. (2011) nghien ciiu hinh chup cd khudn mat ciing tim thay ket qua tuong tu nhu nghien ciiu ciia chiing tdi, la ngudi khdng chuyen mdn, BS RHM tdng qudt vd BS CHRM thdy nu cudi dep nhat khi bd mdi tren eham nudu cd rdng^^l
Nhdm BS RHM trong nghien ciiu ciia chiing toi cd cdc lua chpn tgp trung trong khoang toi uu tir mdi eham cd rdng (dp lp nudu= 0) cho den mdi phu rdng 1 mm chiem ti le 59%. Xet theo phdn loai cua Liebart vd cs. (2004)"^^, day Id loai dudng cudi trung binh va dudng cudi cao. Ket qud ndy gidng vdi ket qud nghien ciiu cua Nguyen Thu Thuy (2007) ve thdm my nu cudi dupe ddnh
gid bdi cac BS RHM vd gidng vien dgi hoc MS^Thudt"^^
Khde vdi cdc BS RHM, nhdm ngodi nganh chpn vi tri tdi uu trong khodng mdi phil rdng tir 1mm den 1,5mm. Su khac bi?t nay giiia hai nhdm cd y nghTa ve m^t thong ke, p<0,01 (Bdng 3.10). Theo phan loai cua Liebart (2004), day Id dudng cudi trung binh""'l Ket qua trong nhdm ngodi ngdnh cua chung tdi cd y kien tuang ddng vdi ket qud cam nhdn ve d?p nu cudi ciia Trdn Thi Nguyen Ny tren doi tupng sinh vien y khoa.
Tac gia nay nhan thay rang tren nu cudi tu nhien, da sd mpi ngudi thich nu cudi chi lp nudu d khoang k6 rdng (dudng cudi trung binh) vd khdng thich nu cudi lp nudu qud nhieu (dudng cudi cao) -
Nghien ciiu cua Ker tren nhdm ngudi ngodi ngdnh cho ket qua gan tuong tu, vi tri ly tudng la mdi phii rdng 2,Imm. Khi lp nudu tir 1mm trd di, ti le cho Id dep ciia BS RHM va ngudi khdng chuyen mdn rdt thdp.
Ket ^ua tir nghien ciiu nay cho thdy ngudi ngodi ngdnh cd xu hudng thich ny cudi vdi mdi phii rang nhe ban la nu cudi Id nudu dii miic Id nudu rdt it (1mm). Geron vd Atalia (2005) ciing cd nhdn xet tuong ty, ngudi ngoai ngdnh cho Id ny cudi kem thu hut khi nhin thdy nudu Id tir 1 mm trd di'^^.
Ve miic dp chap nhdn, mot lan niia ket qud lgi khdng dinh xu hudng tren. Miic chap nhdn mdi phu rang cd khuynh hudng nhieu hon chdp nhdn lp nudu. d cd hai nhom, khoang chdp nhdn mdi phii rdng tir 2 den 3,5mm nhung khodng chdp nhdn cho Id nudu chi tirO den 1,5mm.
Tuy nhien, Ker (2008) thdy rang miic dp chdp nhdn cua ngudi ngodi ngdnh trong khodng ±4mm"''', gidng vdi ket qud nghien cim ban ddu cua Kokich (1999), BS RHM
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CHUYSN p i : HJNH THAI HQC VA C 6 N G NGHg THONG TIN
tdng qudt va ngudi ngodi nganh chap nhan lp nudu 4mm*"', nhung trong nghien ciru ve sau ciia Kokich (2006) tren BS chinh hinh rdng mdt, BS RHM tdng qudt va nhiing ngudi ngodi ngdnh RHM, do giam sy khde bi?t giiia cdc hinh cdn 1 mm nen ngudng chap nhgn miic dp lp nudu la 3mm''^'.
Ny cudi cho thdy lp nhieu thdn rdng ciia ham tren the hien su lr6 trung. trong khi dd, cang Idn tudi thi dp lp nudu cdng gidm ' ' vd cudi cdng lp nhieu rdng cira dudi'^'.
4.6. Y nghia vd irng dung ciia dc tai Qua nghiSn ciiu ndy, chiing tdi cd vdi luu y cho vi?c iing dyng lam sang nhu sau:
• Vd'i khodng chap nhan ciia dp l^ch du&ng giita:
Neu benh nhan cd lech dudng giOa khoang 2,5mm trd xudng, benh nhdn khdng mudn chinh hinh rdng thi phyc hinh cd thi Id mpt chpn lua. Chu y thuc hien phuc hinh sao cho dudng giira rdng song song vdi dudng giua mat va tryc ddi ciia cdc rdng cira dung thi van cd kha ndng cho kit qua thdm my mac dii dudng giira rang khdng triing vdi dudng giiia mat. Ben canh dd, cd thi lam cho rdng ciia ben mdt ben hai nhd trong khodng ti le ve chieu rdng cud rdng ciia ben vd rdng cira giira nhd din 47% dl giiip chinh dudng giita du khdng ly tudng nhung van duoc nhieu ngudi chdp nhdn.
NIU I$ch dudng giiia nhilu hon 2,5mm thi dieu tn chinh hinh mdi cd thi giai quylt dupe van de.
• Ve dp nghieng m^t phdng nhai Neu mdt phdng nhai nghieng dudi 3,5"
va benh nhdn khdng cd vdn dl vl khdp cdn thi khdng nhdt thiit phai dilu trj.
Nlu dp nghieng vuot qud khodng chdp nhan (3,5"), cd thi hudng benh nhdn din dilu trj chinh hinh hay phau thudt. Vdi trudng hop lech nhilu cdn phau thugt nhung benh nhan
khdng cd dilu kifin phau thugt ma dieu trj chinh hinh khdng thi dat dupe kit qua Ij?
tudng thi cung nen dgt myc tieu lam giam d§
nghieng cang nhilu cang tdt dk cdng chiing cd the chap nhgn dugc.
> Ve dp lp rang va nuo^u
Dp lp rdng va nudu thay ddi tiiy dp tuoi.
Theo thdi gian, co mdi se giam truang lyc Idm cho mdi mdng han va dp Ip nudu sg giam ddn. Trong dieu tri, nen danh gia mpt each dai hgn vd ddt vi tri dudng cudi cua benh nhan cho phil hpp trong phgm vi chap nhan de b$nh nhan ludn cd mpt ny cudi dep sau khi kit thiic dilu tri cung nhu nhieu ndm sau dd.
V. KET LUAN
Cd su khac biet ve cam nhan thdm mj"
nu cudi giiia BS RHM va ngudi ngodi nganh trong hdu het cac ddc diem tham m^ ny cudi.
Do dd, BS RHM nen tim hieu quan diem tham my ciia BN khi lap kl hoach dilu tri.
Hdu nhu ket qua nghien ciru khong cho thay su khac biet cd y nghTa Idm sang vl cam nhdn tham my nu cudi khi so sanh theo gidi trong BS RHM va ngudi ngoai nganh.
Cac gid tri tdi uu trong nghien cuu ndy la gpi y ban ddu giiip cdc BS RHM kiln tao ny cudi thdm mj. dem Igi su hai Idng cho benh nhan. Ben cgnh dd, khoang chdp nhan ciia cac yeu td nay ciing nen duoc luu tdm, khong phdi de dp ddt benh nhdn phai theo y kiln cai ma da sd ngudi khac chdp nhgn, ma dl giiip cho benh nhan nhin nhdn vdn dl va nhiing gidi ban cua nd trong timg trudng hpp lam sang mdt cdch thuc tl. Cac nhd chuyen m6n cdn khdch quan va nen dua tren cac b ^ chiing khoa hpc dl cd nhihig quylt dinh chinh xac va giao tilp tdt hon vdi benh nhan khi lap ke hogch dilu tri.
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Y HQC VigT NAM THANG 10 - s 6 PAC BlgT/2013
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