Hoang Tien Cdng va Dig Tap chi KHOA HQC & CONG NGHE
KICH THU"6C RANG, CUNG HAM VA MOT SO CHI SO THONG DUNG TREN MAU THACH CAO CUA SINH VIEN TRUOfNG DAI HQC V DUOC THAI NGUYEN CO SAI KHdP C A N ANGLE II
Ho^ng Ticn Cong'. Trinh Diic Mau^' 'Irmrng Dai hoc ) l)uac-'l)ll lliai \guvOn
'// iiiif: ldm Mia khoa {Jiiiic lc I i(-l Due T O M T A T
Nghien cuu xdc djnh kich thudc rang - cung ham, mot sd chi sd thdng dung v^ nhan \et moi tuang quan cdn khdp giiJa hai hdm tren mlu ham cd sai l^ch khdp cSn Angle M ciia sinh vien y Irudng Dai hoc Y Dugc Thai Nguyen. Thi^t ke nghien ciru mo td cdt ngang. KLM qua: 48 mdu h^m co sai lech khdp can Angle 11 gdm 68,7% tiiu loai I (Cli,,) v^ 3 1.3% li^u loai 2 (Ctu.) Do cdn triim la 4,20 ± 1,67 mm, dp can chia 3,67 ± 1,80 mm. cao hem so vdi gia Irj tuang irng d ngudi binh thudng. Cdc kich thudc ve chieu rdng va chieu dai cung h^m d ca hai h^m (trir D17) deu nhd hon gia tri tuang iing d ngudi binh thudng. Su mat luong xirng ring - ham c6 su khac biet gifta hai ham, thieu chd cho rang d ham tren la 52,1 lo. o ham dudi la 62.5% va 37.5% o ca hai ham, khong CO su khac biet ve gidi. Tuong quan can khap giua hai ham thong qua chi so Bolton co lien quan d^n gidi linh, 31.2% nam gidi co chi so Bolton >91,3 va 10,4% co Bolton < 91,3, ngugc lai, 35.4%
nir gidi co chi s6 Bolton < 9 L 3 v a 2 2 . 9 % c d Bolton <91.3.
TIT khda: Sai lech khdp cdn, dd cdn iriim. do cdn chia, chi sd Bolton, mdu hdm D A T VAN DE
Sai lech khdp can gay ra su bat hai hda trong tuong quan giira cdc rang trong mieng vd gdy dnh hudng nhieu den chirc nang, thdm my va sue khde rang mieng. Sir hieu biet mdt each rd rdng ddc diem ciia cdc loai sai lech k h d p can vd t u a n g quan x u o n g - rang la het siic can thiet de d u a ra ke hoach dieu tri chinh hinh rdng-mdt vdi cdc khi cu thich h a p . Sai lech khdp can loai A n g l e II la lech lac hay gap trong chinh nha, da cd nhieu nghien ciru tim hieu ve loai lech lac nay d Viet Nam ciing n h u tren the gidi Moorrees vd cs (1969), Buschang vd cs (1994), Walkovv vd Peck (2002) [3,7], da phan tich mau ham d e tim sir khac biet ve kich t h u d c c u n g hdm ciia hai nhdm tieu loai I (Cln'i) va tieu loai 2 ( C l u i ) trong sai lech k h d p cdn Angle II c h u a d u g c dieu tri Arias (1999) da phan tich 30 mau ham cua benh nhan cd sai lech k h d p can Angle 11 tieu loai 2 de tim su thay ddi kich thudc cung hdm t r u d c vd sau dieu tri T r o n g nghien ciru ciia Isik F & cs (2006) [5] da tien hdnh phdn tich phiin C e p h a l o m e t r i c s vd mdu ham nhdm tim kiem su khdc biet ve x u a n g - rang gi&a tieu loai 1 va lieu loai 2 ciia sai lech khdp cdn Angle II. Tai Viet N a m trong nhUng ndm qua dd cd nhieu nghien cOru khdo sdt ve
Tel 0989398386
sir phan bd ty le cac loai k h d p cdn trong cdng d d n g n h u Nguyen Phuc Dien Thdo vd Hodng T u Hiing (1993), Pham Thj H u a n g Loan va Hoang T u Himg ( 2 0 0 0 ) . Hodng Thi Bach D u a n g (2000).
De gdp phdn tim hieu dac diem cua loai lech lac nay tren nhdm sinh vien cd sai lech khdp can Angle II, chiing tdi Ihuc hien nghien ciru ndy nhdm hai muc tieu sau:
l-Xdc dinh kich thir&c rdng, cung hdm vd mat so chi so thdng flung tren mdu hdm thach cao ciia sinh vien trtiirng DH Y Dirac Thdi Nguyen cd .sal lech khdp cdn Angle !I.
2-Nlian xet mdi twang i/iian cdn klu'rp gii'ra hai hdnt tren mdu thach cao cda doi tirang nghien ciru.
DOI T U O N G VA P H U O N G P H A P Doi t u g n g n g h i e n c u u
- Sinh vien y chinh quy Irudng Dai hgc Y D u g c Thdi Nguyen cd sai lech khdp can Angle II d u g c chgn ui mot nghien ciru khdo sdt t r u d c dd.
- Tieu chuan lira c h g n : + TLi6itu 18-25.
+ Cd sai lech k h d p can loai 11 theo Angle.
+ Cd dil rdng vTnh vien (tir 28 - 32 rang).
+ C h u a dieu tri phuc hinh hodc chinh hinh 73
Hodng Tien Cdng vd Dtg Tap chi KHOA HQC & CONG N G H ^ 104(04): 73-77 - Tieu chudn lo?i trir: C d tien sir chan thuang
hoac dj tdt bam sinh vimg hdm mgt lam anh hudng den khdp cdn. C d bat Ihuong vc so lugng rang (thira ho^c thieu rdng). Cd mat rang nhung khdng phdi rdng so 8. Cd tdn thuang tren '/i than rdng.
P h u a n g phdp nghien c u u
- Phuang phdp nghien ciiu: M d ta cdt ngang.
- Cac budc lien hdnlv
+ Thu thdp thong t i n : Dga Iren 48 mdu hdm dugc xdc djnh la cd sai Ifch khdp can Angle II ciia sinh vicn \ chinh qu> trudng Dai hgc V Dugc Thai N g u \ e n . chting ldi tien hanh lay sd do cung ham nhu dg rgng trirdc (R33), do rgng sau (R66). Cac dd ddi cung hdm: chieu ddi Irudc ( D I 3 ) , chieu ddi sau (D16), chieu dai toan bg ( D I 7 ) . Do kich thudc cung rang de xdc dinh khodng hien cd Do kich thudc gan xa ciia cac rang tren cung ham de Iinh khoang yeu cau. Danh gia mirc do mat cdn XLi'ng rang - ham thdng qua khoang hien cd vd khoang yeu cau. T i n h chi sd Bolton lodn bg de ddnh gia tuong quan hai ham.
- Xir ly sd lieu bang phdn mem SPSS 16.0.
K E T Q U A N G H I E N C U U
48 ddi tuong tham gia nghien ctru cd do tudi lir 19-24, tudi trung binh la 22.4 ± 0,77.
Trong dd cd 28 n\s (58,3%), 20 nam (41,7%).
Khdng cd su khac biet \'e g i d i . 41,7%
Bdng I. Dg cdn triim. dg can chia ciia cdc doi tugng nghien cdu
CI l l / l
Bicu do I. Phdn bd cdc lieu loai sai lech khdp cim loat II
Nhan xet: cd 33 trudng hgp sai lech Angle II lieu loai I (68,7%o) va 15 trirdng hgp sai lech Angle II lieu loai 2 (31,3%). Su chenh lech ty le sai lech khcrp can Ciu j va Ciu 2 d nam vd nii' khdng cd \ nghTa thong ke vdi p=0,825.
\ ^ 9 i K C Binh
\ . Ihud'ng P$ cdn X.^ (mm)
C l „ ( x ± S D )
(mm) Op can
triim Op cdn chia
2,89 4,20 ±1,67 <0,O0I 2.79 3,67 ±1,80 <0,00l Nh^in xel: Nhdm doi tugng nghien ctJu cd dp cdn triim vd dg can chia cao hon so vdi gia tri luang irng d ngudi cd khdp can binh thudng, voi p < 0,05.
Bang 2. Kich thudc rdng, cung rdng tren mdu thach cao
~ ~ Binh ciii
Chi so thudng (x±SD/mm) p ( x /m m)
D3I 9.60 7,86 ±2,76 <0.00l D6I 28.93 26,98 ±3,10 <0.00!
^^•^ D7I 44.39 44.97 ±3,71 0,283' tren
R33 38,16 35.34±1.95 <0.00l R66 54,90 53,63 ±3,14 <0,01 D3I 6,36 5,41 ±2,04 <0,05 D61 24.06 22.89 ±2.26 <0.001 1^^!" D71 39.50 40.98 ±3,03 <0.001 duai
R33 27.30 26.28 ±2.39 <0,01 R66 53.50 46,65 ±3,27 <0.00l Nhdn xet Cdc mdu hdm Irong nghien ciru co cac kich Ihudc \ e chieu rgng vd chieu dai cung ham o c a hai ham (trir D ! 7 ) d e u nhd hem gid trj tuong ung d ngudi cd khdp can binh thudng.
Bang 3. Su chenh lech giira khodng yeu cdu vd khoang hien cd iheo gidi
\ ( ^ f i Irj TB
Gidi ^ \ Nam NCr
C L „ ( x ± S D / m m )
2 , 1 2 ± 3 , I 2 3,24 ±3,49
P
>0,05
Nhgn xet. Sir mat can xirng rang - ham dita tren sir chenh lech giQ-a khoang yeu cau va khodng hien cd khdng khac biet ve gidi, vdi p > 0 . 0 5 .
Hoang Tign C6ng vd Dig Tap clii KHOA HQC & CONG NGHII 104(04): 7 3 - 7 7
\ H i m trgn Ham d u ' ( ? r \
\ .
X<0 X=0 0<X<2 2<X<6 X>6
I x=Krc-
X<0 (n, % )
4(8.3) 0 ( 0 ) 1(2.1) 2 (4.2) 0 ( 0 ) 7(14.6)
Bang 4, Su mdi
-KHC (khoang.
X=0 (n, % )
1 (2,1) 0 ( 0 ) 0 ( 0 ) 2 (4.2) 0 ( 0 ) 3 (6,2)
cdn ximg rdng 0<X<2 (n, % ) 1(2,1)
0 ( 0 ) 4(8,3) 8(16.7) 0 ( 0 ) 13(27,1) eu cdu - khoang hien cd)
hdm a hai hdm 2<X<6 (n, % ) 1(2,1)
0 ( 0 ) 6(12,5) 8(16,7) 2 (4,2) 17(35,4)
X>6 (n, % )
0 ( 0 ) 0 ( 0 ) 0 ( 0 ) 4 (8,3) 4(8,3) 8(16,7)
I
(n, % ) 7(14,6)
0 ( 0 ) 1 1 (22,9) 24 (50,0)
6(12,5) 48(100) P=0,005 Nhan xet: Sir mat t u a n g xirng rdng - ham cd sir khdc biet giua hai ham vdi p < 0,05. Thieu chd cho rdng d hdm tren chiem 5 2 % , d ham dudi 6 2 . 5 % \ d 3 7 . 5 % d cd hai hdm.
Bang 5. So sdnh dd cdn triim, dp can chia giua 2 nghien cim
DO can C^n chia
Nghien ciru
Cl„„
( x ± S D / m m ) Cl|i,j ( x ± S D / m m )
C l „ „ ( x ± S D / m m )
Ci,,/:
( x ± S D / m m ) Hoang Tien Cong
Isik & cs (2006)
3.75 ± 1,54 4.06 ± 2.27
4,51 ± 1,83 6,17 ±2.48
4,02 ± 1,87 10,02 ±2.37
2,88 ± 1,41 3,67 ± 1.28
Bieu do 2. Chi sd Bolton trong nghien ciru Nhdn xet: S u khac biet ciia chi sd Bolton Iheo gidi. 0 nam gidi cd chi sd Bolton > 91,3 cd ty le cao hon, cdn nir gidi cd chi sd Bolton <91,3 cd ty le cao h a n (P<0,05).
BAN LUAN
Qua phan tich 48 mau ham ciia nhdm sinh vien cd sai k h d p can A n g l e II, cd tudi trung binh Id 22,4 ± 0,77, c h u n g tdi thdy cd 33 trudng hgp (68,7%)) sai lech tieu loai I va 15 trudng hgp ( 3 1 , 3 % ) tieu loai 2. Khdng thay cd su khac biet ve gidi (p>0,05). Ket qud iia\
phii hgp vdi cdc nghien ciru ciia C a o Hodng Yen 2 0 0 7 . Ibrahim (2007) [4] va t h u c liln cho thay sai k h d p cdn loai C I n i m a n g tinh di truyen nen ty le t h u d n g thap h a n , sai lech khdp cdn loai Cl||/| t h u d n g gap do nguyen
nhdn mac phdi n h u cdc tai ihdn kinh-ca chirc nang vd hien t u g n g di gan ciia rang 6 ham tren cung gdp phan lam tang ty le sai khdp can loai Cln |.
Do can triim (4,20 ± 1.67 m m ) , do can chia (3,67 ± 1,80 m m ) deu cao ho'n so vdi gid tri t u o n g irng d ngudi binh t h u d n g (Bang I). Ve mat hinh thai, the hien rd tinh trang vdu. mdt hdi hda hdm tren so \ d i ham d u d i . Cd hai tieu loai deu cd gia trj thap han so vdi nghien cii'u cua Isik F vd cs [5] (Bdng 5)
Ddi t u g n g trong nghien ciru cua Isik & cs Id nhCrng benh nhan den kham nan chinh rdng \ d su khac biel ve chimg idc cd the gidi thich cho su khdc nhau ndy. Tuy nhien, ket qud nghien ciru ciia chimg tdi vd ciia Isik & cs deu cho thdy, nhdm Cln i cd do cdn triim thdp han so vdi nhdm C l n : . n h u n g d o can chia ciia nhdm CIri I cao hon so vdi nhdm C l u i . Ket qud ndy hoan loan phii hgp vdi ly thuyet phdn loai, bdi cac rang ciia tren cua nhdm Cln i cd \ u hii'dng nghieng ngoai nen cd xu h u d n g do can chia tang va rang cira tren cua nhdm Cl||> quap vdo Irong ( k h d p can nap hop) nen do can chia cd xu h u d n g thap hon. Dd can triim vd can chia ldn. k h d p can sau neu khdng d u g c dieu tri, se ga\ sang chdn. tdn t h u o n g td chuc quanh rang va k h d p thdi dirong ham.
75
Hoang Tien Cdng v(> Dtg Tap chi KHOA HQC & CONG NGHE 104(04): 73-77 Trong nghien ciru nay, dg rgng trudc, dg rgng
sau, do dai cung rdng trudc ( D I 3 ) vd dg dai cung rang sau ( D I 6 ) deu nhd hon so vol khdp can binh thudng (Bdng 2) [ 2 ] . Dg ddi cung rdng hdm Iron d Cln/i ldn han Q\\\i2 cd y nghTa Ihdng kc. Phdi chdng vl ly do dg rgng cung rdng hpp vd chicu dai cung rdng ngdn la nguyen nhan phd bicn gd\' nen sai Ipch khdp can trong nhdm ddi lugng nghien ciru. Tuy nhien, d hdm tren ed dg ddi loan bg ( D I 7 ) tuang tyr nhu d ngudi binh thudng. Dieu nay phdi chang cd s^r gdp phdn ctia hi?n tirgng di gdn R6 trong giai dogn ham rdng hdn hgp, cd the do rdng hdm sira so V bj mdt than rdng sdm gay nen hiC'ti lugng ngdn d dg ddi cung rang trudc (D13) va dg ddi cung rang sau ( D I 6 ) . Dieu ndy cho thdy ldm quan trgng ciia cdng lac chdm sdc sire khde rang mi?ng d tre em.
Ket qua ciing cho thay cd sir thu hep kich thudc R33 d cung rang ham dudi ciia nhdm C\[\i. phii hgp vdi nghien ciiu cua Buschang &
cs (1994) va Walkovv & Peck (2002) [3.7]. Su gidm kich thudc do rgng trudc (R33) d eung rdng ham dudi ciia nhdm C l n i c d the la do cac rdng trudc cua ham tren nghieng trong (quap) lam cho can trd sir phal trien ciia xuong d rang hdm dudi.
Su mat can xiirng rang - ham, bieu thj tinh trang cung ham thieu chd cho rang d nhdm nghien ciru kha cao, d ham tren la 52%, d ham dudi la 62,5% va 37,5% d c a hai ham.
Ket qua nghien ciru ciia chiing tdi cho thay cd su khdc biet ve gidi d chi sd Bolton, nam gidi cd chi sd Bolton > 91.3 chiem i\ 1? cao (31,2%), cdn nii' gidi chi sd Bollon < 91.3 chiem t> le cao (35.4%)) Chi so nd> danh gia tinh trang bat hdi hda ve kich thudc rdng giu'a hai hdm, day Id yeu td quan Irong de .\cin xet viec chi djnh nhd rang hay khdng khi lgp ke hoach dieu trj chinh nha.
K E T L U A N
Nghien ciru 48 mau ham ciia sinh vien cd sai lech khdp cdn Angle I I . chiing tdi riit ra mgt sd ket ludn sau:
- Sai lech khdp cdn lieu loai I ( C I n i ) la 68,7% vd 31,3% tiSu loai 2 (Cln,.).
- BQ cdn triim la 4,20 ± 1,67 m m , do can chia 3,67 ± 1,80 m m . Gia trj trung binh dg cdn triim va dg cdn chia cao hon so vdi gia trj luang ung d ngudi binh thudng.
- Cdc kich thuoc ve chieu rgng va chieu dai cung hdm d cd hai hdm (triJ D ! 7) d^u nhd hon gia trj tuong irng d ngudi binh thudng.
- Sg' mat tuong xijng rang - ham khdng khac bi§t ve g i d i , cd s\f khac bi?t giua 2 hdm, thieu chd cho rdng d hdm tren Id 5 2 , 1 % , d hdm dudi la 62,5%o va 37,5% o cd hai ham.
- T u a n g quan cdn khdp giira hai hdm thdng qua chi sd Bolton co lien quan den gidi tinh.
6 nam gidi ed chi so Bolton > 9 I , 3 cd ty 1?
31,2% so voi Bolton < 91.3 Id 10,4%. Ngugc lai, nii" gidi cd chi sd Bolton < 91,3 Id 35,4%, vd Bolton < 91,3 la 22,9%).
T A I L I E U T H A M K H A O [ 1 ] Hoang Thj Bach Duong (2000), "Diiu tra vi lech lac rdng - hdm tre em lua tudi 12 d Irudng cdp II Amsterdam Hd Ndi", Luan van Ihac sy y hoc, Dai hpc Y Hd Ngi.
[2], Pham Thi Huang Loan, Hoang Tir Hung (2000). '"Nghien cuu dSc diem hinh ihdi cung rSng ngudi Viet". Tinvn lap edng trinh NCKH Rdng Hdm Mgi. DH Y Dugc Tp Hd Chi Minh.u95-106.
[3]. Buschang PH., Stroud J, and Alexander RG.(I994). "Differences in dental arch morphology among adult females with untreated Class 1 and Class II malocclusion", European Journal of Orthodontics 16, p.47-52 [4]. Ibrahim E.G et al (2007). "Prevalence of Malocclusion Among Adolescents in Central knaxohd.". Eur J Dent, 1(3). p.l25-I31.
[5]. Isik. F., Nalbantgil D. .Saymsu K. et al (2006). "A comparative study o f cephalomeiric and arch width characteristics of Class II division I and division 2 malocclusion", Eur J Orthod, 28(2). p.179-183.
[6]. Louly F.. Roberto P.A.N, et al, (2011),
"Denial arch dimensions in the mixed dentition, a study of Bra:dian children from 9 lo 12 years of age". Journal of Applied Oral Science, 19 (2), p. 132-137
[7]. Walkow T. M; Peck. S (2002), "Dental arch width in Class II division 2 deepbile malocclusion". Am J Orthod Dentofacial Orlhop, 122 (6). p. 6 0 8 - 6 1 3 .
Hoang Tien Cdng vd Dtg Tgp chi KHOA HQC & CONG NGHE 104(04). 73 - 77
S U M M A R Y
T E E T H S I Z E , D E N T A L A R C H M E A S U R E M E N T S A N D S O M E C O M M O N I N D I C A T O R S O F T H E S T U D E N T ' S C A S T S O F T H A I N G U Y E N U N I V E R S I T Y O F M E D I C I N E A N D P H A R M A C Y W I T H A N G L E ' S C L A S S II M A L O C C L U S I O N Hoang Tien Cong', Trinh Due Mau^
'College o/ Medicine and I'harmacy - '/A t',
• 1 'let Due Cenler oj InWrnalional Dental The purpose of the studv is lo determine the teeth size, dental arch measurements, common indicators and comments occlusion's correlation ofthe casts wilh Angle's Class II malocclusion.
Cross-seclional descriptive study was conducted on the student's casts of Thai Nguyen University of Medicine with Angle's Class 11 malocclusion which have a full permanent denture and prosthetic or orthopedic untreatmenl. Results: 48 casts with Angle's Class 11 malocclusion consists of 68.7% division 1 (Cln , ) and 31.3% division 2 (Cim). Overbite is 4,20 ± 1,67 mm, overjel is 3,67± 1,80 mm, higher than the corresponding values in normal people. The dental arch width and length measurements on both dental arches (except D17) are smaller than the corresponding values in normal people. The significanl difference of tooth-dental arches inadequate between maxillary and mandibular, the lack of space for the teeth in the upper jaw is 52,1%, lower at 62,5% and 37,5% in both, there is an insignificant difference in sexes.
Bite relationship between two jaw through Bolton index related to gender, in males Bolton index >
91.3 rate of 31,2yo and Bolton<91,3 is 10.4%, In contrast, females with Bolton index <9I,3 rate of 35,4%, and Bollon >9I,3 is 22,9%.
Keywords: Maloccluston.Overhtte, Over/el. Bollon Index, Cast
Ngdy nhdn bdi:20/3/2013, ngdy phan bien 02/4/2013, ngdy duyel ddng-24/4/2013
Tel. 0989 398386
