A Classification of Dental Composites According to Their

7/25/2019 A Classification of Dental Composites According to Their

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Dent Mater 8:310-319 September 1992

class i ficat ion of d en ta l co m po si tes acc ord ing to the i r

m orpho logica l and m ech anica l cha racter is t ics

G . W i l l e m s ~ P . L a m b r e c h t s ~ M . B r a e m 2 J . P . C e l is 3 G . V a n h e r l e 1

1Department o f Op erat ive Dent i s try and Dental M aterials , Kathol ieke Unwers~te i t e Leuven, Leuven, Belgium

2Dental Propedeut~cs, Un iversi ta ir Centrum Antw erpen RU CA ), Antwerp, Belgium

3Department o f M etal lurgy and M aterials Engineering MT M ), Kathol ieke Universite~t e Leuven, Leuven, Belgium

Abst ract . Th e on-going sea rch for a bio logically acceptable

restora t ive ma ter ia l has brough t a confusing v ar iety of com posi tes

on the dental ma rket . In

t h e p r e s e n t

study, comm ercially avai lable

composi tes are categor ized as a funct ion of thei r mean par t ic le

s ize, f i l ler d is t r ibut ion, f i l ler content , Young's modulus, sur face

roughness , compress i ve s t rength , sur face hardness , and f i l ler

mo rphology. Ou t of th~s nformat ion, i t can be conclude d tha t t h e

mater ia ls of choice for restor ing posten or ca vi t,es at present a r e

t h e

Ul t raf ine Compact -Fi l led Composi tes because thei r ~nt r ins ic

sur face roughness , Yo ung 's modu lus and, i nd i rec t ly , their f i l ler

content , compress ive s t rength , and sur face hardness are compa-

rable

t o t he

same proper t ies of enamel and dent in. The Ul t raf ine

Midway-F i ll ed C omp os, tes seem to be very sa t ,s fac tory m atena ls

for antenor use.

I N T R O D U T I O N

T h e i n c r e a s e d n e e d f o r e s t h e t i c t o o t h - c o lo r e d r e s t o r a t i v e

m a t e r i a l s h a s b r o u g h t a c o n f u s in g v a r ie t y o f c o m p o s i te s o n to

t h e d e n t a l m a r k e t . T h e o n - g o i n g s e a r c h f o r a b i o lo g i ca l ly

a c c e p ta b l e m a t e r i a l t h a t n o t o n l y h a s p h y s ic a l a n d m e c h a n i -

c a l p r o p e r t i e s s i m i l a r t o n a t u r a l t o o t h t i s s u e s b u t a l s o i s

e c o n o m i c al ly a n d m a n i p u l a t i v e l y e q u i v a le n t t o a m a l g a m h a s

d r a m a t i c a l l y i n c r e a s e d t h e n u m b e r o f d e n t a l c o m p o s it e s

a v a i l a b l e .

T o k e e p t r a c k o f r e c e n t ly d e v e l o p e d m a t e r i a l s a n d t o

c a t e g o r i z e o t h e r s , s e v e r a l c l a s s i f ic a t i o n s h a v e b e e n p r o p o s e d .

T h e A m e r i c a n D e n t a l A s s o c i a t i o n d e s c r ib e d t w o c a t e g o r ie s o f

d i r e c t f i l l in g r e s i n s i n S p e c i f i c a t i o n No . 2 7 (C o u n c i l o n De n t a l

M a t e r i a l s , A m e r i c a n D e n t a l A s s o c ia t i o n , 19 77 ). M o r e e l ab o -

r a t e r a n k i n g s a r e b a s e d o n t h e s p e ci fi c f i ll e r- s iz e d i s t r i b u t i o n

a n d a m o u n t o f i n c o r p o r a t e d f i ll e r ( L u tz a n d P h i l l ip s , 1 9 8 3;

Al b e r s , 1 9 85 ; L e i n fe l d e r , 1 9 8 5 ) a s we l l a s o n f i l le r a p p e a ra n c e

a n d c o m p o s i t io n ( H o s o d a

e t a l . ,

1990).

F i l l e r c o n t e n t a n d s iz e w e r e s h o w n to d i r e c t ly d e t e r m i n e

t h e p h y s i c a l a n d m e c h a n i c a l p r o p e r t i e s o f c o m p o s i t e m a t e r i -

a l s

L i e t a l . ,

1985 ;

B r a e m e t a l . ,

1 98 9; C h u n g , 1 9 9 0 ; C h u n g a n d

G r e e n e r , 1 9 90 ), o f w h i c h t h e d y n a m i c Y o u n g s m o d u l u s ( B r a e m ,

1 98 5; B r a e m

e t a l . ,

1 9 86 ) , s u r f a c e h a rd n e s s (C ra i g , 1 9 8 9 ) a n d

i n t r i n s i c s u r f a c e r o u g h n e s s ( W i l le m s

e t a l . ,

1 9 9 1 a) s e e m t o b e

t h e m o s t c l in i c a ll y r e l e v a n t f o r t h e i r m e c h a n i c a l p e r f o r m a n c e .

T h e p u r p o s e o f t h e p r e s e n t s t u d y w a s t o r a n k m o s t o f t h e

c o m m e r c i a l l y a v a i l a b l e c o m p o s i t e s a s a f u n c t i o n o f h e i r m e a n

p a r t i c l e s i z e, f i l l e r s iz e d i s t r i b u t i o n , f i l le r c o n t e n t , Yo u n g s

m o d u l u s , s u r f a c e r o u g h n e s s , s u r f a c e h a r d n e s s , c o m p r e s s i v e

s t r e n g t h , a n d s c a n n i n g e l e c t r o n m i c r o sc o p e ( S E M ) a p p e a r -

a n c e .

MATERIALSAND METHODS

T a b l e I l i st s t h e 8 9 c o m m e r c i a l ly a v a il a b l e c o m p o s i t e s i n v e s -

t i g a t e d i n t h i s s t u d y . A p p r o x i m a t e l y 3 g o f e a c h c o m p o s i t e w a s

d i s s o l v e d i n a c e t o n e p ro a n a l y s i (AC S , IS O, 1 4 .1 0 0; M e rc k ,

D a r m s t a d t , G e r m a n y ) , m i x e d a n d c e n t r if u g e d fo r 30 r a i n a t

3 0 0 0 r p m . T h e r e m a i n i n g s o l u ti o n o f a c e t o n e a n d d i s s o l v e d

r e s i n w a s c a r e f u l l y r e m o v e d b y p i p e t t e a s p i r a t i o n w i t h o u t

a g i t a t i n g t h e c e n t r i f u g e d f il le r p a rt i c le s . T h i s p r o c e d u r e w a s

t h e n r e p e a t e d a s e c o n d ti m e t o c o m p l e t e ly re m o v e r e m n a n t s

o f r e s i n m a t r ix . T h e s u p e r n a t a n t w a s a g a i n r e m o v e d a n d t h e

r e m a i n i n g f il le r p a r t ic l e s d r i e d a t 3 7 C f o r 1 2 h . F i n a l l y , t h e

p o w d e r w a s u l t r a s o n i c a l l y a g i t a t e d to r e d u c e a g g l o m e r a t i o n o f

f i ll e r p a r t i c le s . A l l p o w d e r s w e r e s c r e e n e d u n d e r S E M ( P S E M

5 0 0 , P h i l l ip s , E i n d h o v e n , T h e N e t h e r l a n d s ) t o c o n f ir m c om -

p l e t e f i l l e r i s o l a t i o n a n d t o i n v e s t i g a t e f i l le r m o rp h o l o g y .

A c o m p u t e r - c o n t r o l le d a p p a r a t u s ( C o u l t e r L S S e r i e s 1 0 0,

C o u l t e r E l e c t r o n i c s I n c . , H i a l e a h , F L , U S A ) , u s i n g l a s e r -

d i f f ra c t i o n t e c h n o l o g y ( l a s e r l i g h t o f 7 5 0 n m ) , w a s u s e d t o

d e t e r m i n e p a r t i c l e s i z e d i s t r i b u t i o n . T h i s e q u i p m e n t c a n

a n a l y z e a s a m p l e w i t h a p a r t i c le r a n g e o f 0 . 4 t o 8 00 ~ m . L i g h t

i s d i f fr a c t e d a r o u n d a p a r t i c le a t a n g l e s i n v e r s e l y p r o p o r t i o n a l

t o t h e s i z e o f t h e p a r t i c l e . T h e s m a l l e r t h e p a r t ic l e , t h e g r e a t e r

wi l l b e t h e a n g l e o f d if f r a c t i o n (F ig . 1 A) . M o s t l a s e r -d i f f r a c t i o n

p a r t i c l e - s i z e a n a l y z e r s h a v e o n l y a s i n g l e o p t i c a l s y s t e m (F i g .

1 B ) fo r c o l l e c t in g a n d s e n s i n g d i f f r a c t e d l i g h t . S i n c e o n e o p t i c a l

s y s t e m i s n o t c a p a b l e o f c a p t u r i n g t h e f u l l r a n g e o f d i f f ra c t e d

l i g h t ( f ro m v e ry l a rg e t o v e ry s m a l l p a r t i c l e s ) , t h e c o l l e c t i n g

l e n s m u s t b e c h a n g e d o r a d j u s t e d w h e n d i ff r ac t io n a n g l e s

e x c e e d t h e l e n s c a p a b i l i t i e s . M u l t i p l e o p t i c a l d e t e c t i o n s y s -

t e m s (F i g . 1 C ) a l l o w t h e p a r t i c l e - s i z e a n a l y z e r t o s i m u l t a -

n e o u s l y c a p t u r e t h e d i f f r a c te d l i g h t o f a w i d e r a n g e o f p a r t i c l e s

v a ry i n g i n s i z e f ro m 0 . 4 t o 8 0 0 p ro . T h e d i f f r a c t e d l i g h t i s

c o l le c t e d b y a F o u r i e r l e n s , w h i c h f o c u s e s t h e l i g h t u p t o a b o u t

1 5 o n t w o s e t s o f d e t e c t o r s, o n e f o r l o w - a n g l e s c a t t e r i n g a n d

t h e o t h e r f o r m i d - a n g l e s c a t te r i n g . A n o t h e r F o u r i e r l e n s

s y s t e m (m u l t i p l e o p t i c a l d e t e c t i o n s y s t e m s ) c o l l e c t s t h e d i f -

f r a c t e d l i g h t f r o m a b o u t 1 0 to 3 5 a n d f o c u s e s i t o n t o a t h i r d

s e t o f h i g h -a n g l e d e t e c t o r s (F i g . 1 C ) .

A h i g h - v ol u m e p u m p p u s h e s t h e p a r ti c le s t h r o u g h t h e

31

Wl l l em s e t a l C l as s l hc a t l on o f den t a l c om pos z t es


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T A B L E : A LP H A B E T I C L I S T OF M A N U F AC T UR E R S

MANUFACTURER B rand Name

C I T Y , S T A T E / C OU N T R Y B a t c hN o

3M

St P aul , MN, USA

Bayer

Dormagen, Germany

~ s c o

Lombard, IL, USA

Caulk De ntsply

Milford, DE , USA

Coltene

Altstatten, Sw itzerland

Den-Mat

Santa M ana, CA, USA

Denta l Compos ite L ]D

Kent , England

DentaI -Matenai

Gesel lschaf t MBH

Hamburg, Germany

Espe

Seefeld, Germ any

G C

Tokyo, Japan

Jenenc/Pentron

W alhngford, CT, US A

Johnson & Johnson

East W indsor, N , USA

Kanebo

Tokyo, Japan

Kerr

Basel , S witzerland

Kulzer

Fnednchsdorf , Germ any

Kuraray

Osaka, Japan

Lee P harmaceut icals

South E l Mo nte, CA, USA

Pierre Roland

Amiens, France

Tokuyama Soda Co LTD

Tokyo, Japan

Vwadent

Schaan, l iechtenstein

Conc ise, P -1 0, P -3 0, P -30 APC, P -50 APC, S i la r , S i lux , S i lux P lus , V a lu x , -100

A 1994 / 81994 , 112983 , E X P LOT 5 , 5E 35P / 5G 81P , E 8J D 03 / 1D X 2 , A 8601 / B 8601 , 0411835502U 4Y 30A M 2* / 9B R 2D , 6G 1 , 5904 A 2

Luml for , Pe kaf i l l , P eka lux

5 5 08 E , O 1 6 5 F , 2 0 3 8 D / 2 0 4 5 D / 4 0 9 0 S

Bis-Frl I , BIs-FII M, B Is-F II

0 6 8 3 0 7 , 1 0 8 2 5 9 , 0 7 8 2 1 9 / 0 3 9 1 1 1

B~ogloss, FuI-F~I , Fu I-FdComp, Pnsma AP H , P r i sma-Fd,

8 4 0 5 2 2 , 1 0 0 7 8 7 3 , 8 8 0 9 1 9 , 1 0 1 5 8 8 / 0 2 1 4 8 9 , 9 0 3 87 5 ,

Bnlhant , Br i l liant D en t in , B nl ha nt ~rect nlay,

1 5 0 5 8 4 - 3 6 , 0 1 0 9 8 8 - 0 2 3 - 9 0 , 1 2 0 48 9 -1 8 ,

M a r a t h o n , P e r f e c t i o n

249010 / 247019 , 285017

Gem-CCI, Gem -Dte I

B 0989450 / C 0589421 , 0989451

Superlux Mo lar, Superlux Solar

00938. 01O84

Pnsm a-F~lComp, P nsma-MJcrof ine, Pnsm a-M~crof ineComp,

880614 , 1113862 , 880418

Bnlhant Lux

030489 -08

N;met~c, N~met~cDJspers,

0014 L157 , L139 009 + 012 , 0008 ,

Epohte 100 , Graf t LC,

B 221181 C 251 081 , 221281 / 211281 / 050192 ,

Conques t D FC, Pos tComp I I

180931 . 860832

AdaptJc, Adap tic I I , Ada ptlc LCM ,

053183 3A 001 , 8E 5103 / 8J 5107 ,8G 1403 / 112988B , 840 514 CH -B 4135 .

Bell FJrm

1N D 3N

Comm and Ul t raf ine,

1 8 4 1 2 8 6 B S U 3 0 3 4 4 ,

Chansma,

931231 021 / 94063022 ,

Est r lux Poster ior CVS,

3 0 0 6 9 2 3 3 / 3 00 6 9 1 2 0 2 1 /3 1 1 2 9 1 2 2 , 0 6 1 9 8 4 034, 83 027,

Clearf i l , Clearf i l Lu stre , Cle arf i l Photo P ostenor,

43005 B F X C -0204 + C F X C -0104 , 17 -17106 /17107A , H P S 1001 ,

Res to lux S P-4

9310R P 1D 0

A m a l u x , A m a l u x , A m a l u xSintergel NC, Sm terlux2

4 0 5 3 6 , 6 1 0 3 9 , 4 0 53 6 , 7 0 29 3

Pal f ique Estel i te, P al f ique Lrte, Pa l f iqueLJte Posterior

EU 206, LU 205, PU 601

Hehomolar , Hehomolar Radlopaque, He ho Progress, HehosJt,

0 5 0 3 8 4 , 4 7 0 2 0 1 / 4 5 2 8 0 1 , 4 5 2 9 0 1, 2 2 1 C -1 D - 2 B 0 2 0 5 8 4 ,

Pertac H ybrid, V lsJoD ispers, V ls lo FI I,

0105, 0204,

MIcrorest AP, Occlusm ,

2 3 0 2 4 1 , 4 1 3 6 2 4 # 5 / 1 / S M 4 0 ,

Adapt lc RadJopaque, Answer,

V~slo Molar R adfopaque

0 0 0 4

Opalux

EA140/UM120

Aurafi l l , Certarn, Mlradap t

201804 / 21300 , L60 4170 , 0217849 / 3L1604 , 2D 951 / 1 E 951

Hercuhte Condensable, HercuhteXR

041385 0779 5 0787 , E X P 1092 / O 1275

Durafrl l , Du rafi l l VS, Estlc Microfi l l, Estrlux Hy brid VS ,

300692 161 , 311291 030 , 0684 045P + 131 C , 30 069 2 33 ,

Estdux Poster ior XR1,

Estdux P ostenor,

83 I 61 ,

Estl lux P osterior XR 2, Multf f~llV S

311291 025 / 300691

Clearf i l R ay , Clearf i l Ra y Posterior, Ph oto Clearf i l A

1100B , 1018, HAS 1004

Isomolar, Isopast

B 551183 + C 701183 , 22 B 430484 + C 370484

T A B L E 2 : R E F R A C T IV E I N D E X E S OF F ILLE R P A R T I C LE S

Z i rconrum G lass 1 520

Yt terbium t rff luonde 1 530

Quar tz 1 540

Banum 1 550

Stront ium Glass 1 550

Barrumborosdicate 1 554

Polystyrene Latex 1 650

di f fr a c t ion sa m ple c e ll f our t im e s a m in u te a n d ke e p s he a v ie r

pa r t i c le s i n suspe ns ion . Du r ing t e s t ing , a n u l t r a son ic m ixe r

m a xim iz e s d i spe r s ion . As the sa m ple pa r t ic l e s m ove th r ough

the c el l, t he l a se r l i gh t pa ss ing th r oug h i t i s d i r e c t e d on the

pa r t i c le s f o r m e a sur e m e nt a n d i s d i f f ra c t e d fr om e a c h pa r t i c l e

a nd the n c o l le c t ed by th e op t ic a l de t e c t ion sys t e m .

T hi s d i f f ra c t ion m e thod , a lso know n a s t he F r a un hof e r

op t ic a l m ode l Coul t e r E l e c tr on i c s I nc .) , m a ke s use o f t he

d i f fr a c t ion pa t t e r n f o r m e d whe n a be a m of l i gh t f a ll s on to a

pa r t ic l e . T he F r a u nh of e r op t i c a l m ode l i s, how e ve r , re l a t i ve ly

ina c c u r a t e f o r pa r t i c le s o f 3 pm or l es s . Sm a l l pa r t i c le s ha ve

Dental Matenals September 1992 311


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T A B L E 3 : DENSIF IEDCOMPOSITES:MIDWAY-FILLED

PROD UCTS MPS Mo Ra Y-Mod Vol%A Vol%B C S H V

U l t r a f i n e M i d w a y - F i l l e d C o m p o s i t e s

Comm and Ultraf ine* 1.1 0.9 0 21 14,803 52.5

Hercul ite condensable 0 9 0 8 0.12 14,871 52.6

Hercuhte XR 1 0 0 8 0 .12 16 ,042 55 2

Charisma 0 7 14 ,060 50 7

Conquest DFC 0.8 17,511 58 1

Biogloss* 3.4 3.9 0 34 1 5,190 53.3

Bnl l iant* 2.8 3.1 16,586 56.3

B r i l l i a n t D irect Inlay 2.2 2.0 0.20 17,176 57 5

Br i lhant Lu x* 2 1 1.8 0.19 14,451 51 7

Bn l liant Dent in 3.6 10.0 0.11 15,821 54 7

Luml for * 2 0 1 8 0 21 13 ,208 48.6

Pekaf il l 1.7 1.2 15,514 54 0

Post Comp I I LC 2 .7 2 8 16 ,079 55 3

Pnsma APH 3.1 3 5 0 .29 13 ,644 49.7

F i n e M i d w a y - F i l l e d C o m p o s i t e s

FuI-F il compules 6 0 8 1 0 39 13 ,842 50 2

FuI-Fi l* 6 0 8.1 0.50 14,465 51 7

Per tac Hybnd 4 .2 8 1 15 ,062 53 1

Gem-CCI 7 6 11 .2 0 .94 18 ,487 59 9

G em-bte I 9 3 12 .4 0 .46

Pnsm a-Fil Compules 8 4 12.4 0 68 13,362 49.0

Pr isma-Rl* 7 .3 10 0 0 60 14 ,251 51.2

Super lux Molar 5 .5 4 3 13 ,984 50 6

49.9 344

58.0 414

5 7 0 3 9 7

59.4 417

68 5 483

51.9 350

53.9 328

5 6 5 3 4 2

49.8 330

55 2 377

54.8

5 5 2

70.0 345

383

8 7

6 5

7 4

81

9 5

7 3

8 5

7 0

8 4

8 4

8 4

9 7

7 7

52.3 372 87

52.8 97

61.0 450 126

61.8 117

64 4 144

51 0 353 79

52.0 83

60 .0 343 90

MP S. m ean particlesiz e (~tm);Mo: modeof he particle size distribution (~tm),Ra intrinsicsurface roughness ~tm),Y-Mod. Young 'sModulusof e lasticity (MP a),V o I A

inorganic f il ler volum e percentage as calculated according to Braem (19 85), VoI%B: norganic i l ler volume percentage as obtained rom the manufacturers;C S :

compressive strength (MP a); HV : V lckers H ardness kg/mm 2), Y oung 's modulus data aken from B raem (198 5)

A

S

E

R

HorLzonta

Adustment~ ~ 0

HoT~zonaA~usmen

~~ ~ ~ .~

ETECTOa

F i g 1 L L g h t S d i f fr a c t e d a r o u n d a p a r t i c le a t a n g l e s i n v e r s e l y p r o p o r t i o n a l t o t h e s i z e

o f t h e p a r t i c l e . T h e s m a l l e r t h e p a r t i c l e , t h e g r e a t e r w i l l b e t h e a n g l e o f d i f f r a c t io n ( A ) .

M o s t l a s e r d i ff r a c ti o n p a r t ic l e m z e r s h a v e o n l y a s i n g l e o p t ic a l s y s t e m ( B ) f o r

c o l l e c t i n g a n d s e n s i n g d i f f r a c t e d l i g h t . T h e r e f o r e , t h e c o l l e c t i n g l e n s m u s t b e

c h a n g e d o r a d j u s t e d w h e n d i f fr a c t io n a n g l e s e x c e e d l e n s c a p a b i l it ie s . M u l t ip l e

o p t i c a l d e t e c ti o n s y s t e m s ( C ) a l l o w t h e C o u l te r L S S e r i e s p a r t i c le s l z e r t o c a p t u r e

s i m u l t a n e o u s l y t h e d i ff r a c te d l ig h t o f a w i d e r a n g e o f p a r t i c le s v a r y i n g i n s i z e fr o m

0 . 4 t o 8 0 0 i lm .

3 1 2 Wtflems et al /Classlhcatton of dental composi tes

high d i f fr a c t ion a ng le s a n d som e t im e s d i f f r a c t e d l i gh t i s

e r r one ous ly de t e c t e d by the op t ic a l de t e c t i on sys t e m . T he r e -

f o re , to c om pe nsa t e f o r t h i s e r r o r , t he c on t r o l - c om pute r e n-

a b l e d the ope r a to r t o c a l c u l a t e a ne w op t i c a l m ode l a s a

f u n c t io n o f t h e r e a l a n d i m a g i n a r y r e fr a c ti v e i n d e x o f s am p l e

pa r t i c le s a nd m e dium d i s t il l ed wa te r ) whe n 20 vo l o r m o r e

of he sa m ple pa r t i c l e s a ppe a r e d to be sm a l l e r t ha n 3 ~ tm . T h i s

process i s com puter -con t rol leda nd i s ne c e ssa r y o inc r e a se t he

a c c ur a c y o f he d e t e r m in a t ion o f he pa r t i c l e s iz e d is t r ibu t ion .

Table 2 l i s t s th e re f rac t ive index es of f i l le r par t ic les o bta ined

f r om m a nuf a c tu r e r s a nd use d f o r c a lc u l a t i ng the se spe ci fi c

opt ica l models .

T he a c c ur a c y o f t he pa r t i c le s i z e a na lyz e r wa s c h e c ke d by

m e a ns o f po lym e r l a t e x pa r t i c le s w i th a kno wn r e f r a c t ive

inde x ( Po lys ty r e ne L a tex , C oul t e r E l e c t r on i cs I nc .) i n t e nde d

f o r t h i s p u r p o s e. T h e i r m e a n p a r ti c le d i a m e t e r a n d s t a n d a r d

devia t io n of 1 .14_+0.72 ~m w as v ery a ccu ra te ly reproduced .

T he m e a n pa r t i cl e s i z e s (M PS) f o r t he s tud i e d c om pos i te s a r e

g ive n in T a b le s 3 t o 8 , t oge the r w i th t he m ode o f fi l le r

d i s t r i bu t ion ( M o). T h is i s t he pa r t i c le s i ze wh ose f r e que n c y o f

oc c ur r e nc e is g r e a t e s t .

F o r s e v e r a l t e s t m a t e r i a ls ( m a r k e d w i t h a n a s t e r is k i n

T a b le s 3 t o 8 ), t he d yna m ic Young~s m o dulus w a s d e t e r m ine d

non- de s t r uc t ive ly by Br a e m ( 1985) a nd Br a e m e t a l (1986).

T h i s s t u d y u s e d t h e s a m e s a m p l e p r e p a r a t i o n a n d t e c h n i q u e

t o d e t e r m i n e t h e Y o u n g 's m o d u l u s f o r t h e m o r e r e c e n t m a t e -

r i al s . B r a e m ( 1985) ha s p r opose d a phe nom e nolog ic a l m ode l

for denta l co mpo si tes given by Eq. 1:

E = 3,1 03.3 3 e 002977172ox (1 )

wh e r e E i s t he Young ' s m o dulus a nd X i s t he pe r c e n ta g e o f


4/10

TABLE4: D E N S I F I E DCOMP OSITES COMP ACT-F ILLED

PRODUCTS MPS Mo Ra Y-Mod Vo l%A Vo l%B C S H V

~ ~ p a c t F i l l e d C om posites

Adapt~c I I 3 2 3.9 0.48 21,876 65 6 66 5

P - 3 0 * 2 8 7 3 0 6 7 2 3 ,3 8 5 6 7 8 6 9 9

P - 3 0 AP C 3 0 2 5 0 7 1 2 3 ,1 5 5 6 7 5 6 9 0

P - 5 0 AP C 2 1 1 2 0 4 8 2 5 ,0 0 7 7 0 1 7 7 0

Pa l f ique L~te Pos te r io r 3 6 5 9 26 ,293 71 .8 73 0

V a lux 2 4 2 3 0 2 7 1 9 ,7 2 8 6 2 1

Z - 1 0 0 1 0 0 8 0 2 7 2 1 ,0 3 0 6 4 3 7 1 0

Fine Com pact FilledComposites

BIs-R I I 8 .2 10 0 0 80 19 ,991 62 6 74 0

B i s -R I P 2 0 ,2 1 9 6 3 0 7 4 0

Clear f il Pho to Pos te r io r 7 .5 10 0 0 53 25 ,343 70 5 71 0

Clear f il Ray 8 0 10 0 1 18 27 ,384 73 1 69 0

Clear f il Ray Pos te r io r 8 2 12 4 0 65 26 ,435 72 0 71 0

E s t ll ux H y b n d V S 8 8 1 2 4 0 9 0 2 2 ,5 9 4 6 6 7 6 8 4

Est t lux P oster iorCV S 9 6 1 2 4 1 4 8 2 4 ,5 0 8 6 9 4 6 8 4

G r a ft L C 6 7 8 1 1 2 6 2 1 ,7 1 9 6 5 4

Marathon 7 9 10 0 1 07 20 ,343 63 2 68 0

O c c lu sm * 8 6 1 2 4 0 9 9 2 3 ,7 7 4 6 8 4 6 9 0

O p a lu x 8 9 1 2 4 0 7 9 2 2 ,3 3 6 6 6 3

P-10 (Pas teA - B )* 5 1 - 3 6 1 0 0 - 3 9 1 0 2 2 5 ,1 1 7 7 0 2 6 9 1

Photo C lear f i lA 7 9 1 0 0 1 1 7 2 5 ,2 2 5 7 0 4 6 9 0

Ws~o Mo la r Rad lopaque 7 5 10 0 1 08 26 ,754 72 4 68 4

3 8 0

340

3 9 4

3 9 5

421

4 3 0

4 4 8

106

107

157

159

143

107

120

345 102

339 114

408 159

3 5 0

408 174

345 130

345 133

332 128

299 100

348 125

277 111

390 174

350 166

400 186

MPS meanpar t tc les ize(pm);Mo modeofthepar t tc leslzedrstr ibut ion(pm);Ra ntnnstcsur faceroughness(pm);Y-Mod'Young'sModulusofelast lc i ty(MPa),Vol%

~norgan~c il le r volum e percen tage as ca lcu la ted according o Braem (1985 ) , V o l%B' =norgan~c il ler volum e percen tage a s ob tained rom the m anufacturers,CS

compressivestrength (MP a), - IV Vicke rsHardness kg /mm2), Young 's modu lus da ta aken rom Braem (1985)

volum e t r i c fi ll e r. I nor ga n i c f i ll e r vo lum e p e r c e n t a ge s we r e

de r ive d f r om E q . 1 fo r t he e x pe r im e nta l l y ob t a ine d Young ' s

modu l i . The se theore t ica l va lues (Vol A) a re l i s ted in Tables

3 to 8 next to the v olum etr ic fi l le r perc enta ges (Vol B) com-

p i le d f r o m h t e r a t u r e a n d m a n u f a c t u r e r s ' in f o r m a ti o n .

W i th a c om pute r i z e d r ough ne ss t e s t e r ( For m T a lysu r f 10,

Ra nk T a y lor Hobson , L e i c e s t er , E ng la n d , UK) , t he a ve r a ge

r ough ne ss ( Ra ) o f c om pos i t e su r f a c e s wa s m e a su r e d a f t e r a

too thbr ush- de n t i f ri c e a br a s ion t e s t . T he b r u sh ing p r oc e ss wa s

pe r f o r m e d w i th a m o di f ie d M in im e t m a c h ine ( Bue h le r , L a ke

Bluf f, I L , USA) a nd wa s e x t e ns ive ly de sc ribe d i n a n e a r l i e r

repo r t (Wil lems e t a l . 199 l a ) . Re c e n t ly de t e r m in e d r oughne s s

va lue s we r e c om bine d w i th t he r e su l t s o f t h i s p r e v ious ly

r e por t e d s tudy .

A V i c k e rs d i a m o n d p y r a m i d i n d e n t e r t e s t w a s u s e d f o r

d e t e r m i n i n g t h e m i c r o h a r d n e s s o f co m p o s it es . T h e p r o c e d u r e

c o v e re d th e r e q u i r e m e n t s o f t h e S t a n d a r d T e s t M e t h o d f o r

M i c r o h a r d n e s s o f M a te r i a l s ( Am e r i c a n Soc i e tyf o r T e s t i ng a n d

M a t e r i al s , 1 9 8 4 ). H a r d n e s s m e a s u r e m e n t s w e r e m a d e w i t h

a D u r i m e t m i c r o h a r d n e s s t e s t e r ( L e i t z G m b H , W e t z l a r ,

Ge r m a ny) w i th a l oa d o f 100 g. T e n i nde n t a t i ons we r e p r o -

duc e d f o r e a c h sa m ple . T he a ve r a ge V ic ke r s ha r dne s s i s g ive n

in T a b le s 3 t o 8 . P r io r to m e a su r e m e nt , t he spe c im e ns , 5 m m

i n d i a m e t e r a n d 5 m m h i g h , w e r e e m b e d d e d i n e p o x y r e s in

( Ar a ld it e DRL a nd Ha r de n e r HY956 , C iba Ge igy , D i lbee k ,

Be lg ium ] a nd a f t e r wa r d s m e ta l l ogr a ph ic a l l y po l i she d a c cor d-

m g to a p r e v ious ly re por t e d po l i sh ing p r oc e dur e ( Wi ll e m s e t

a l . 1991a ). I n a dd i t i on , V ic ke r s ha r dn e ss wa s d e t e r m ine d f o r

h u m a n e n a m e l a n d d e n t i n ( T a b l e 9 ) . F o r b o t h t o o t h

subs t a nc e s , a t o t a l o f 22 V ic ke r s i nde n t a t i ons w e r e m a de

i n s a m p l e s o f t h r e e h u m a n t e e th , w h i c h w e r e e m b e d d e d i n

the sa m e e pox y r e s in a nd sub j e c t e d t o t he sa m e p o l i sh ing

procedure .

T h e c o m p r e s s i v e s t r e n g t h v a l u e s f o r a l l m a t e r i a l s

w e r e t a k e n f r o m t h e l i t e r a t u r e a n d f r o m m a n u f a c t u r e r s '

i n f o r m a t ion .

Addi t i ona l SE M inv e s t i ga t ion wa s c a r r i e d ou t t o i l l us t r a t e

f i l le r morphology. I sola ted f i l le r par t ic les were spread on

double - side d a dhe s ive a nd e l e c tr oc onduc t lve t a pe ( L e i t e nde s

Kle be ba nd A16 , Ba lz e r s , Z a ve n te m , Be lg ium ) m oun te d on a n

SE M s tub . L oose powd e r pa r ti c l e s we r e r e m ov e d by a i r

p r e s sur e , a n d t he sa m ple wa s c o a t e d w i th a l a ye r o f pur e go ld

by va por iz a t i on in a n a r gon ga s a tm o sphe r e ( SE M c oa t ing um t

E -5100 , P o l a r on E q uipm e nt L im i t e d , Wa t f o r d , E ng la nd ,UK) .

A se lec t ion of pho tom icrograph s i s given in Figs . 2-8.

RE S UL T S

T he r e su l t s o f t he d i f f e r e n t inve s t i ga t e d p r ope r t i e s a r e l i s te d

m T a b le s 3 to 8 . S inc e t he a m o un t o f ge n e r a t e d da t a wa s qu i t e

e x t e ns ive , t he 89 c om pos i t e s a r e a l r e a dy d iv ide d i n to f i ve

ca tegor ies : Densi f ied Com posi tes , Microf ine Composi tes , Mis-

c e l la ne ous Com pos i te s , T r a d i t i ona l C om pos i t e s a nd F ibe r -

Re in f or c e d Com pos i te s . T h i s r a nk ing i s ba se d on t r a ns i t i on

areas in c r i te r ia such as Young' s Modulus , inorganic f i l le r

vo lum e pe r c e n t , m e a n pa r t i c le s i ze , i n t r i ns i c su r f a c e r ough-

ne ss , su r f a c e ha r dne ss , a nd c om pr e ss ive s t r e ng th . Add i t iona l

SE M inve s t i ga t ions we r e p e r f o r m e d to c onf i rm f i l le r m or pho l -

ogy (Figs. 2-8).

T h i s n e w c l a ss i fi c a ti on is p r e se n t e d v i sua l l y in F igs . 9 a n d

10 and wi ll be fur th er review ed in the discuss ion sec t ion.

T a b le 9 l i s ts t he a ve r a ge V ic ke r s ha r dn e ss a n d s t a n da r d

d e v i at i o n o f h u m a n e n a m e l a n d d e n t in . T h e s e v a l u e s c a n

Dental Materia ls~September 99 2

313


5/10

T A B L E :

MICROFINECOMPOSITES

PPF Mo Ra Y-Mod Vo l%A Vo l%B C S H V

P R O D U C T S M P S

H O M O GE N E O US M I CR O F IN E COMPOSITES

H E T E R O GE N E O US MICROFINECO M P O S I T E S

w i th s p l in t e r e d p r e p o l y m e r i z e d f i ll e rs

Cer ta in * 0 04 14 2 15 3 0 08 8 ,770 34 .9 31 4 365 43

Dura f il l* 0 04 17 0 18 9 0 11 6 ,085 22 .6 37 5 463 48

Dura fi ll VS 0 .04 15 .5 25 9 0 .16 6 ,154 23 .0 37 5 474 45

Est ic M ic ro f il l* 0 04 11 7 15 .3 6 ,473 24 7 36 1 41 5

Heho Progress 0 04 17 9 18 9 0 12 9 ,098 36 1 43 .0 330 50

Hehos it * 0 04 13 6 15 .3 0 07 6 ,401 24 3 24 3 400 36

Isomola r* 0 .04 16 .5 25 9 9 ,619 38 0 45 3 390

Isopas t (Base-Cat )* 0 04 20 8 -12 .8 39 5 -15 3 0 13 5 ,436 18 8 23 2 359

Micro res t AP* 0 04 17 0 32 0 8 ,679 34 5 17 1 304

Mult if il l VS 0 04 16.6 39.5 7,833 31 1 55

Per fec tion 0 04 5 ,620 20 0 25

Pnsm a-Microfine Compules 0.04 25.5 48 8 0 22 6,612 25.4 42

Pr isma-Microf ine 0 04 29.8 54.2 0.19 5,700 20 4 262 39

S i la r Pas te (A-B)* 0 04 20 .8 -21 3 18 9 -48 .8 0 13 9 ,075 36 0 35 4 283

S l lux* 0 .04 20 .0 39 5 0 10 9 ,372 37 .1 36 .3 344 46

S~lux P lus 0 .04 22 .0 39 .5 0 .13 9 ,466 37 5 59

Super lux So la r 0 .04 16 .0 31 9 7 ,905 31 4 41 0 324 5 5

w i th a g g l o m e r a t e d p r e p o l y m e r i z e d f il le r s

Adapt ic LCM 0 .04 13 0 18 9 0 .21 9 ,692 38 3 498 55

Answer (Un i-Cat)* 0 04 13 3 -20 7 12 4 -32 0 0 16 9 ,932 39 1 39 7 303 63

He l iomo la r * 0 04 12 .4 18 9 0 .09 10 ,612 41 3 49 1 325 61

N imettc b ispers* 0 04 13 .8 13 9 10 ,147 39 8 40 5 455

w i th s i n t e re d a g g l o m e r a t e s

Am a lu x * 0 0 4 1 2 4 3 2 0 0 2 2 1 3 ,3 7 2 4 9 0 3 9 0 3 0 4 4 7

Amalux Sm terge l NC 0 04 5 2 5 3 0 25 11 ,918 45 .2 39 .0 70

S ln te r lux 2 * 0 04 8 .0 5 9 0 .33 9 ,384 37 .2 55

w i th s p h e r ic a l p r e p o l y m e r i z e d f il le r s

M P S

m e a n pa rticle size (~tm),P P F' m ean par t ic le s ize of prepolymenzed i llers and sinteredagglomerates,M o m o d eof the p article stzedlstnbut=on ~m ),

R a

intnns=c

sur face roughness ~m); Y-Mo d: Young 's Modulus of e last ic i ty (MPa); Vol% A inorganic i l ler volume percentageas calculated according o Braem (19 85), Vol%B:

inorganic f i l ler volum e percentag eas obtained rom the manufacturers, CS compressivestrength (MPa ), HV V lckers Hardness (kg/mm2), *You ng's modulus data

taken f rom Braem (1985)

se r ve a s a ba s i s f o r c om pa r i son f o r t he i nv e s t i ga t e d de n ta l

m a te r i a l s . V ic ke r s ha r d ne ss va lue s o f he M ic rof ine , M idwa y-

F i l le d a nd Com pa c t - F il l e d c om pos i te s b r oa d ly r a ng e f r om 25

to 63, f rom 65 to 97 an d f rom 100 to 186, respec t ive ly.

D I S C U S S I O N

Com pos i t e s ha ve be e n a v a i l a b l e t o t he de n ta l p r o f e ss ion f o r

m a n y y e a r s . T h e m a s s o f d a t a g e n e r a t e d a b o u t t h e v a r i o u s

c om pe t ing p r oduc t s i s ve r y c onf us ing , a nd r a nk ing the d i f fe r -

e n t m a te r i a l s a c c or d ing to t he i r l a bo r a to r y r e su l t s doe s no t

ne c e ssa r i l y r e f l e c t t he i r c l in i c a l pe r f o r m a nc e ( L a m br e c h t s

e t

a l .

1987).

T he c r i t e r i a use d in t h i s s t udy to de sc r ibe t he c o m m e r c i a ll y

a va i l a b l e c om p os i t es we r e c a r e f u l ly se le c t ed . F i r s t o f a ll , t he

inor ga n ic f i l l e r f r a c t i on in vo lum e pe r c e n t a nd the m e a n

pa r t i c l e s i ze a r e c r i t e r i a on w hic h m o s t c l a s s i fi c a ti ons a r e

ba se d ( L u tz a n d Ph i l li ps , 1983 ; A lbe r s , 1985 ; L e in f e lde r,

1 98 5). O n e a d v a n t a g e o f t h e p r e s e n t s t u d y i s t h a t t h e m a t h -

e m a t i c a l c a l c u l a t i on use d to d e t e r m in e the pa r t i c le s i z e d i s t ri -

b u t i o n w a s d o n e u s i n g t h e s a m e a l g o r it h m i n h e r e n t to t h e

pa r t i c le s i z ing a ppa r a tus , so t he a c q u i r e d ind iv idua l da t a c a n

a c c u r a t e l y b e c o m p a r e d w i t h o n e a n o t h e r .

How e ve r , a n e l a bor a t e c a t e gor i z a t i on shou ld be ba se d on

a dd i t i ona l c r i t e r i a in o r de r t o ob t a in a m o r e a c c ur a t e de sc r ip -

t i on o f t he m a te r i a l . T he Young s m odulus i s a v e r y se ns i t ive

pa r a m e te r f o r e va lua t ing a nd r a nk ing pa r t i c l e r e in f o r c e d

c om pos i t e s (Br a e m , 1985 ; Br a e m e t a l . 1986) . Inde e d , a

m a te r i a l w i th a l ow m o dulus w i ll de f o r m m or e unde r m a s t i c a -

to r y s t r e s se s , pa r t i c u l a r ly i n pos t e r io r r e g ions , re su l t i ng in

c a t a s t r oph ic f a i l u r e s ( A lbe rs , 1985 ; L a m br e c h t s e t a l . 1987).

T he m os t a ppr opr i a t e m od ulus o f e l a s t i c i ty f o r a c om pos i te

w o u l d b e o n e c o m p a r ab l e to t h a t o f d e n t i n a n d a m a l g a m

( N a k a y a m a

e t a l .

1974). Ad di t iona l ly , the expo nen t ia l depen-

de nc e o f he Young~sM o dulus on the vo lum e t r i c f i ll e r f r a c ti on

of f er s a n oppor tun i ty t o c he c k the vo lum e t r i c f il l er pe r c e n t -

a ge s ob t a ine d f r om m a nuf a c tu r e r s . For se ve r a l p r oduc t s ,

t he r e a r e obv ious d i f fe r e nc e s be tw e e n the se v a lue s . S inc e t he

phe nom e nolog ic a lm ode l ha s p r ove n i ts va l id i t y (Br a e m e t a l .

1987), one m a y we l l que s t i on the i n f o r m a t ion som e m a n uf a c -

tu r e r s r e l e a se r e ga r d ing th i s p r ope r ty .

An othe r c r i t e r ion to c o ns ide r i s t he i n t r i ns i c su r f a c e r ough-

ne ss o f a m a te r i a l . T h i s su r f a c e c ond i ti on is a c h i e ve d a f t e r

e x t e ns ive too thbr ush- de n t i f r ic e a br a s ion o f he c om pos i te a nd

i s a n i n h e r e n t c h a r a c te r i st i c o f t h e m a t e r i a l t e s t e d t h a t

de te rmin es i t s c l inical behav ior , l ike sur fa ce gloss, s ta ining

a nd f ri c ti on . An e n a m e l su r f a c e r ough ne ss va lue a t e na m e l - to -

en am el occ lusa l contac t a reas of 0 .64 _+ 0.25 ~m is consid ered

t o b e t h e s t a n d a r d w i t h w h i c h t o c o m p a r e t h e r o u g h n e s s

3 1 4 W~ l lems e t a l C lass lhca t l on o f d en ta l com pos i t es


6/10

T A B L E :

MISCELLANEOUS COMPOSITES

PRODUCTS MPS Mo Ra Y-Mod Vo l%A V o l%B CS H V

w i th s p l in t e r e d p r e p o l y m e r i z e d f il le r s

B e l l

F i rm (Un i- Ca t) 2 0 - 7 4 0 . 8 - 1 0 0 9 6 3 2 4

B is -R I M 10 4 12 3 0 58 12 ,882 47 8 59 .0 301 63

Clea r f il Lustre 12.9 12 4 0.74 11,511 44 0 387 100

Pa l f lque Es teh te 13 4 15 3 12 ,132 45 8 56 0 373 63

Pa l f lque L i te 15 1 15 3 12 ,118 45 8 56 0 373 70

w i th a g g l o m e r a t e d p r e p o l y m e r iz e d f il le r s

Vis~o D ispers* 15 0 15 3 0 26 10 ,786 41 8 47 6 455 63

Hehomola r Rad iopaque 13 1 15 3 0 13 9 ,755 38 5 48 0 340 56

w i t h s i n t e r e d a g g l o m e r a t e s

Am a lu x 2 6 4 4 7 0 4 4 1 4 ,1 6 6 5 1 0 3 4 3 8 9

w i th s p h e r ic a l p r e p o l y m e r iz e d f il le r s

P e k a lu x 1 6 1 1 5 3 0 1 8 5 ,9 7 3 2 2 0 5 4 7 2 7 5 2 7

T AB L E 7 : T R AD I TIO N AL COMPOSITES

Adapt~c (80 ' s )* 15 4 18 8 1 26 21 ,412 64 9 56 3 234

Adapt ic Rad iopaque UnJ-Cat)* 13 5 -8 1 18 8 -12 4 1 08 19 ,616 61 9 55 0 240 121

Aura f il l* 8 6 12 4 0 85 17 ,935 58 9 62 0 345 105

C le a rh l l* 9 7 1 2 4 0 8 3 2 0 ,3 7 3 6 3 2 5 8 1 2 5 2 9 3

Conc ise* 1 44 22 ,531 66 6 56 8 241

E p o l it e 1 0 0 ' 1 0 1 1 2 4 1 4 6 1 8 ,2 0 6 5 9 4 5 3 0 2 5 3 1 0 7

Est l lux Pos tenor* 9 5 12 .4 0 88 17 ,408 57 9 58 1 294 96

E st i lux PostenorX R I * 5 1 1 1 1 2 1 ,8 0 5 6 5 5 6 6 2

Est~luxP o s te n o r X R 2 8 8 1 2 4 3 4 6

Ml radap t * 7 8 10 0 1 01 20 ,320 63 1 60 1 310 112

N lmet ic (Un l -Cat )* 14 4 -12 4 32 0 -25 .9 0 91 20 ,908 64 1 58 9 330 149

V l s lo F I I* 7 5 8 1 1 2 3 2 1 ,7 2 3 6 5 4 6 4 4 3 5 0 1 6 0

T AB L E 8 : F IB E R - R E IN F O R CE D COMPOSITES

Resto lux SP -4 11 2 15 3 1 19 23 ,839 68 5 125

M P S m e a n p a r t l c le s i z e p m ) ,M o . m o d e o f t h e p a r t lc l e s J z e d r s t n b u t ~ o n p m ) , R a

ntransicsur faceroughness(pm),Y-ModYoung 'sModu luso fe las t lc i ty (MP a),Vo l%

inorganic f i l ler volum e percentage as calculatedaccording to Braem (1985 ) , V o l%B inorganic i l ler volum e percentageas obtained ro m he manu facturers,C S

c o m p r e s s i v e

strength (MP a), HV V ickers H ardness kg/mm2), * Young's modulus data aken f rom Braem (1985)

va lue s o f c om pos i t e s ( Wi l le m s

e t a l . ,

1991a).

T h e s u r f a ce h a r d n e s s o f t h e d e n t a l r e s t o r a t iv e m a t e r i a ls

w a s m e a s u r e d . T h e r e l a ti v e i m p o r t a n c e o f a V ic k e rs h a r d n e s s

t e s t l i e s i n t he f a c t t ha t i t t h r ows l i gh t on t he m e c ha n ic a l

p r ope r t i e s o f t he m a te r i a l s i nve s t i ga t e d . T h i s i s t r ue b e c a use

o f t h e r e l a t i o n w h m h e x i s ts b e t w e e n h a r d n e s s a n d o t h e r

phys ica l prop er t ies (O 'Nei ll , 1967) . The Vicke rs har dn ess

va lue s p r e se n t e d i n t h i s s t ud y we r e ob t a ine d a f t e r com ple t e

pos t - po lym e r i z a t ion o f t he sa m ple s , w hic h p r oduc e d som e -

w h a t h i g h e r h a r d n e s s v a l u e s ( A t m a d j a a n d B r y a n t , 1 9 9 0).

F ina l l y , c om pr e ss ive s t r e ng th va lue s ob t a ine d f r om the

l i t e r a tu r e a r e g ive n . T he c om pr e ss ive s t r e ng th , i n pa r t i c u l a r ,

indica tes the ab i l i ty ofa m a te r i a l t o w i ths t a n d ve r t i c a l s tr e s se s,

whic h i s v i t a l in h igh s t r e s s a r e a s .

A l l c om pos i te s we r e r a nk e d i n a c l a s s i fi c a ti on c on t a in ing

f ive ca tegor ies : Densi f ied Co mposi tes , M icrof ine Comp osi tes ,

M isc e l l a ne ous Com pos i t e s, T r a d i t i ona l Com pos i t es , a nd F i -

be r - Re in f orc e d Com pos i t es . A ge ne r a l ove r v i e w i s g ive n i n

F igs. 9 a nd 10. Com pos i t e s i n t e nde d f o r pos t e r io r use shou ld

h a v e a Y o u n g 's m o d u l u s a t l e a s t e q u a l t o t h a t o f d e n t i n

( N a k a y a m a e t a l . , 1974) a nd p r e f e r a b ly h ighe r . De n t in ha s a

Youn g' s mo du lus of 18,500 M Pa (Cra ig, 1989) . This cor re -

sponds t o a n im a g ina r y vo lum e pe r c e n t a ge o f 60 a c c or d ing

to E q . 1 ( Br a e m , 1985) . T he r e f o r e , t he g r oup o f De ns i f i e d

Com pos i t e s wa s subd iv ide d i n to two c l a s se s, M idwa y- F i l le d

(Table 3) and Compact -Fi l led (Table 4) , according to the

T A B L E 9 : A V E R A G E V lC K E R S H A R D N E S S V AL U E S ( A V ) A N D

S T AN D AR D D E V I AT IO N S S D ) O F H UM AN E N AM E L AN D

DEN TIN (N = NUMB ER OF INDENTATIONS)

AV S D n

enamel 408 33 22

dent in 60 4 22

a m oun t o f i nor ga n i c f i ll e r c on t e n t , 60 vo l

respec t ive ly. Each c lass was fur ther divided into two sub-

c lasses , Ul t ra f ine (MPS 3 pm) , as a

f unc t ion o f he m e a n p a r t ic l e s iz e o f he c om pos i t es ( I nokosh i

e t a l . , In press) . Indeed, acco rding to Lem felder (1985), the

we a r r a t e o f c om pos i t e s c a n be su bs t a n tm l ly r e duc e d by

decrea s ing the f i l le r par t ic le s~ze and by inc reas in g the inor -

ganic f i l le r f rac t ion. Higher f i l le r leve ls resul t in increased

st i f fness , hard nes s , and comp ress ive s t re ng th (L1

e t a l . ,

1985;

B r a e m

e t a l . ,

1989). The Hetero gen eou s Micro ine Com posi tes

(Table 5) as wel l as th e M isce l laneous C ompo si tes (Table 61

we r e subd iv ide d a c c or d ing to t h e t ype o f p re po lym e r i z e d

or a gg lom e r a t e d f il le r s use d . T a b l e s 7 a nd 8 g ive t he r e su l t f o r

the T r a d i t i ona l Com pos i te s a nd t he F ibe r -Re in f or c e d Com -

posi tes , respec t ive ly. In addi t ion, the int r ins ic su r face rough-

ne ss o f c om pos i t e s shou ld be l e ss t ha n o r e qua l t o t ha t o f

e na m e l - to - e na m e locclusal contact areas

W i l l e m s e t a l . ,

1991a).

T a b le 9 a l so g ive s t he ob t a ine d a v e r a ge V ic ke r s ha r d ne ss o f

Dental Matenals September 1992

3 1 5


7/10

F i g . 2 .

B o t h U I tr a fl n e C o m p a c t -F i ll e d C o m p o s i t e s A d a p t i c I I A ) a n d P - 5 0 A P C B ) a r e h e a v il y f il le d w i th r a t h e r s m a l l

i n o r g a n i c p a r t i c le s . A t p r e s e n t , t h e y a r e t h e m a t e r i a ls o f c h o i c e f o r r e s t o r in g p o s t e r io r c a v i t i e s b a r = 1 0 ~ m ) .

F i g . 3 .

C o m m a n d U l t ra f in e , a n U l t ra f in e M i d w a y -

F i ll e d C o m p o s i t e , is c o m p o s e d o f v e ry f i n e b a r iu m -

g l a s s p a r t ic l e s w i t h a n a v e r a g e p a r t ic l e s i z e o f

1 , 1 p . m . T h i s t y p e o f c o m p o s , t e y ie l d s g o o d e s t h e t ic s

a n d i s s tr o n g e n o u g h to w i t h s ta n d m a s t l c a to r y

s t r e s s e s i n a n t e r i o r r e s t o r a t io n s b a r = 1 0 ~ m ) .

F i g . 4 . S d u x P l u s A ) is a li g h t c u r e d H e t e ro g e n e o u s

M i c r o f in e C o m p o s i t e w i t h s p l in t e r e d p r e p o l y m e r i ze d

f il le r s . A n s w e r B ) i s a c h e m i c a l ly c u r e d H e t e r o g e n e o u s

M I c r o f in e C o m p o s i t e w i th a g g l o m e r a t e d

p r e p o l y m e r i z e d f i ll e r s . B o t h m a t e r i a ls h a v e

a p p r o x i m a t e l y t h e s a m e p r o p e r t ie s . T h e y d i ff e r m a i n l y

i n th e m a n u f a c t u r in g p r o c e s s o f th e i r p r e p o l y m e n z e d

f i l le r p a r t ic l e s . S i l u x P l u s c o n t a i n s fi ll e r s o f a m o r e

a n g u l a r s h a p e w h e r e a s t h e f i l le r p a r ti c le s o f A n s w e r

a r e m o r e r o u n d b a r = 2 0 ~ m ) .

F i g 5 .

F u I - F d C o m p u l e s A ) i s a F i n e M i d w a y - F i ll e d

C o m p o s i te . D u e t o i ts f a ir l y l a r g e p a r t ic l e s , i t is l e s s

e s t h e t c a l l y p l e a si n g t h a n h e U l t r a fm e M i d w a y - F il le d

C o m p o s i t e s . G r a ft L C B ) i s a F i n e C o m p a c t - F il le d

C o m p o s i te . I t s b i g f il l e r p a r t i c le s a r e e x p e c t e d t o

i n c r ea s e t h e o c c l u s a l w e a r r a te o f t h e m a t e r i a l,

T h e s e r e s i n c o m p o s i t e s a r e t h e r e fo r e l e s s s u it a b le

f o r p o s t e r i o r u s e b a r = 2 0 l ir a ) .

h u m a n e n a m e l a n d d e n t i n w h i c h c o rr e la t e s w i t h l i t e r a t u re

da ta (Ca ldw ell

e t a l .

1957; Ryg e

e t a l .

1961; O Br ien an d Ryge,

1978 ; Cra ig , 1989) . Res to ra t ive ma te r i a l s ca n be com pared

w i th thes e s t andards .

The U l t r a f ine C ompac t -F i l led Com pos i t e s (Tab le 4 a nd

F ig . 2 ) a r e ve ry p rom is ingma te r i a l s fo r pos te rio r u s e w he n a l l

o f the above is t ak en in to accoun t . They have a Y oung s

mo du lus tha t i s h ighe r than tha t o f den t in (Craig, 1979), and

they hav e a h igh a m oun t o f ino rgan ic pa rt i c le s . They a l s o

d i s p lay goodV i c k e rs h a r d n e s s v a l u e s c o m p a r e d to d e n t i n a n d

re la t ive ly h igh com pres sive s t r eng th va lues , w h ich s ugges t s

that they are able to suppor t occlusal

s t r e s s es . F u r the rmore , the i r s u r f ace

roughnes s r anges f rom 0 .48 ~ tm to

0 .71 pm , w h ich i s ve ry s imi la r to tha t o f

enamel (Wil lems

e t a l .

1991a) . The

U l t r a f ine Compac t -F i l led Com pos i te s

a re th us the m a te r i a l s o f choice fo r

res tor in g pos ter ior cavi t ies .

T h e U l t r a f i n e M i d w a y - F i l l e d

Com pos i tes could be very sa t is factory

m a t e r i a l s f o r t h e r e s t o r a t i o n o f

anter ior tee th (Table 3 and F ig . 3) .

T h e y h a v e a Y o u n g s m o d u l u s th a t i s

h igh en ough to r e s i s t the func t iona l

s t r e s s es w h ich a r e l e s s impor tan t in

a n t e r i o r r e s t o r a t i o n s w h e n n o r m a l

occlusion is con sidere d (Howell and

Brudevold , 1950; De Boever

e t a l .

1978;

Craig , 1989) . Th eir re la t ively low in-

t r in s ic roughn es s is due to th e i r ve ry

small par t ic le s ize (MPS


8/10

F ~ g 6

The sph er ical prepolymer ,zed f i l ler par t ic les of

Pekalux, a Miscel laneous Composi te , are c lear ly

apparen t (bar = 20 pm ) .

F i g 7 Adap t lc ~s a Tradi t ional Co mp osi te . These

c om pos i t e s a r e o l de r m a t e r ia l s a nd a r e now r a r e ly

used (bar = 20 pro)

F i g 8 The Ftber-Remforced Com posi te , Restolux SP-

4 c on t a ins g l a s s c e r a m t c f i be rs w i th a m a x t m um

length of 300 pro, which are em bedde d in resin matr ix

(bar = 20 m) .

DENSIFIEDCOMPOSITES

MICROFINECOMPOSITES

TRADITIONALC O MP O S IT E S F IB E R - R E IN F O R C E DOMPOSITES

F i g 9

Categor i zat ion of compost tes

f ine ly divided colloida l s i l ica of 40 n m avera ge p ar t ic le s ize

( Aer os il , D e gussa AG, Ha na u- W ol f ga ng , G e r m a n y) c ons ide r-

a b ly i nc r e a se s t h e m a te r i a l s v i sc osi t y a nd j e opa r d i z e s i t s

ha nd l ing c ha r a c t e r i s t i c s ( L a m br e c h t s a nd Va nh e r l e , 1983). I t

shou ld be no t e d t h a t t he M PS- va lue o f 0 .04 pm l i s te d i n T a b le

5 f o r t he M ic r o i ne Com pos i t e s r e pr e se n t s a c om m only a c -

cepted m ea n par t ic le s ize o f the f ine ly divided col loida l s i l ica .

Sl ight var ia t io ns in the s ize of thes e s i l ica par t ic les do exis t ,

r an gin g f rom 0.007 to 0 .115 pm (Albers, 1985). However , the

pa r t ic l e -s i z e a na lyz e r on ly m e a su r e d t he m e a n p a r t i c le s i z e o f

p r e po lym e r i z e d r e s in f i ll e rs a nd s in t e r e d a g g lom e r a t e s whic h

i s r e pr e se n t e d by t he P PF- va lue i n T a b le 5 .

Both F ine M idw a y- a nd F ine Com pa c t - F i l le d subd iv is ions

( T a b le s 3 a nd 4 , a nd F ig . 5 ) c on t a in c om pos i t e s w i th a n

apprec iably higher par t ic le s ize (6-10 pin) , r esul t ing in a

decre ased pol i shabi l i ty . A s s ta ted above , bigger par t ic les a lso

t e nd t o i nc r e a se the w e a r r a t e o f he m a te r i a l s . T he se com pos -

i tes a re , therefore , less sui table for ante r io r or poste r ior use ,

respec t ive ly.

M isc e l l a ne ous Com pos i t e s ( T a b le 6 ) a r e m a te r i a l s t ha t

c on t a in a b l e nd o f p r e po lym e r i z e d a nd i nor ga n i c f i ll e rs . T he

l a t t e r a r e som e t im e s i n t e n t i ona l l y a dde d t o i nc r e a se t he

r a d iopa c i t y o f he se c om pos i te s . T r y ing to r a nk t he se m a te r i -

a ls i s ve ry di f f icul t becaus e of the i r he te roge neo us composi -

t ion. Fig. 6 shows Pekalux, a Misce l laneous Composi te wi th

spher ica l prepo lym er ized fi l le r s .

The T radi t iona l Com posi tes (Table 7 and Fig. 7) a re older

m a te r i a l s a nd a r e no l ong e r p r om ote d . T r a d i t i ona l Com pos -

i t e s ve r y o f t e n c on t a in l a r ge qua r t z pa r t i c l e s t ha t a r e ve r y

ha r d . E xposur e o f he se f i ll e r pa r t ic l e s be c a use o f e s in m a t r i x

we a r r e su l t s i n a h ighe r su r f a c e r oughne ss a nd c l in i c a ll y a du l l

a ppe a r a nc e . I n a dd i t ion , qua r t z l a c ks t he r a d iopa c i t y r e qu i r e d

for poste r ior res tora t io ns (W il lems e t a l . , 199 lb) . M ost of hes e

c om pos i te s ha ve t he r e f o r e be e n r e p l a c e d by p r oduc t s w i th a n

improv ed f i l le r concept .

Fina l ly , the las t subdivis ion conta ins the Fiber -Reinforced

Com posi tes (Table 8 and Fig. 8). Restolux SP-4 was th e only

inve st iga ted produ ct in this group. This comp osi te i s com-

pose d o f g la s s - c e ra m ic f ibe r s o f a m a xim um l e ng th o f a pprox] -

m a te ly 300 p r o. Re s to lux SP- 4 ha s a ve r y sa t i s fa c to r y Young s

mo dulu s and could per form wel l in poste r ior cavi ties . How-

e ve r , i t s r a the r h igh i n t r i ns i c r oughne ss a nd r e l a t ive ly ha r d

glass ceram ic fi l lers (Willems

e t a l .

I n p r e s s ) p r oba b ly would

ge n e r a t e s i gn i f i c an t ly h igh e r we a r va lue s c om pa r e d w i th t he

e n a m e l s t a n d a r d ( L a m b r e c h ts e t a l . . 1987; 1989) . This m ake s

the m a te r i a l l e ss su i t a b l e a s a n a m a lg a m sub s t i t u t e .

Da ta on Young s m odulus , V lc ke rs ha r dne ss a nd su r f a c e

r ough ne ss w e r e a s se m ble d i n F ig . 10 f o r 62 c om pos i te s . T he se

62 m a te r i a l s , o f whic h d a t a f o r a l l t h r e e p r op e r t i e s wa s

ava i lable , r epre sen t a l l subdivis ions of he c lass i f ica tion int ro-

duc e d in t h i s a r t ic l e . T hr e e m a in g r oups c a n c l e a r ly be

d i f f e r e n t ia t e d . T he se a r e t he M ic rof ine Com pos i t es , t he

Midw ay-Fi l led Com posi tes and the Com pact -Fi l led Compos-

i tes . There i s a lso a t r en d for a fur the r subd]vimon (Ul t ra f ine

v e r s u s Fine ) o f t he l a s t two g r oups m e nt ione d , ba se d on t he i r

su r f a c e r oughne ss w hic h r e f le c t s t he i r m e a n pa r t i c l e si ze . T he

T r a d i t i ona l Com pos i t e s a r e s i t ua t e d ne x t t o t he Com pa c t -

F i l le d Com pos it e s. T h e y e xh ib i t a r a th e r h igh su r f a c e r ough-

n e s s. T h e s e m a t e r i a l s a r e n o w a b a n d o n n e d a n d r e p la c e d b y

technologica l ly impro ved produ cts . C hem ica l -cured compos-

i tes such as the Tradi t iona l Composi te Epol i te 100 (c i rc le

Dental Matenals September 1992 3 1 7


9/10

E

, , . , , .

r , , ,

C l a s s i f i c a ti o n o f R e s i n C o m p o s i te s

1.50

12o

I

0 .9 0

0.301

l l [

0 . 0 0 , - -

2675o 19733

M I C : FCF

: U M F ,~ '

M I S

FMF o : T R A

UCF : FRC

/r

O

1 8 6

107 ~

12717 5700

Y o u n g s Mod ulus (MP a)

The c ompa r i son of p rope r ti e s

such as int r ins ic surface rough-

n e s s , Y o u n g s m o d u l u s , w h i c h

reflects their fi l ler content , com-

pre s s i ve s t r e ng t h , a nd sur fa c e

ha rdne ss be t we e n c ompos i t e s a nd

h u m a n e n a m e l a n d d e n t i n sh o w e d

t h a t t h e U l t r a f ine Com pact -Fi ll ed

C o m p o s i t e s a r e t h e m a t e r i a l s

of choice for res tor ing pos te r ior

cavi t ies. The Ultrafine Midway-

Fi l l ed Comp osi tes seem to be very

sa t i sfac tory mater ia l s for ante r ior

use.

Received February 25 1992/

Accepted July 31 1992

Addresscorrespondenceand repnnt equests

to

G Wfllems

Department of Operatwe Dentistry and

Dental Materials

Kathoheke Umversltelt te Leuven

U Z St Raphael

Kapucljnenvoer7

3000 Leuven Belgmm

Fig 10 T h r e e - d i m e n s i o n a l g r a p h r e p r e s e n t i n g t h e o b t a i n e d d a t a o n Y o u n g s m o d u l u s , s u r fa c e r o u g h n e s s a n d V c k e r s

h a r d n e s s . C o m p l e t e d a t a s e t s w e r e a v a i l a b l e f o r 6 1 c o m p o s i t e s . ( M I C : M i c r o fi n e

C o m p o s i te s ; U M F : U l t r a f in e (F r ee )

M i d w a y - F i l l e d C o m p o s i t e s ;

FM F: F i n e M i d w a y - Fd l e d C o m p o s i t e s ; U C F : U l t r a f i n e (F i n e )

C o m p a c t - F i l l e d C o m p o s i t e s ;

FCF: F ine

C o m p a c t - F il le d C o m p o s i t e s ; M I S : M i s c e l la n e o u s C o m p o s i t e s ; T R A : T r a d it io n a l C o m p o s i t e s ;

FRC: F iber -

R e i n fo r c e d C o m p o s i t e ) .

ma rke d w i t h a n a s t e ri sk ) a nd t he M i dwa y-F il le d C ompos i t e

Gem-CCI (c ross marked wi th an as te r i sk) c lear ly di splay

h i ghe r su r fac e roug hne ss due t o t he i nc orpora ti on o f a i r

bubbl e s a nd vo i ds dur i ng t he r e qu i re d mi x i ng proc es s . The

d i a mond ma rk e d wi t h a n a s t e r i sk r e pre se n t s t he C ompa c t -

Fi l l ed Compo si te Valux. I t s su rface roughn ess , however ,

s l ight ly approximates the Midway-Fi l l ed Composi te range ,

bu t i t s Young s modul us a n d V i c kers ha rd ne ss c l ea r ly be long

to the rang e o f the Com pact -Fi l l ed Com posi tes . Idea l ly , high

Y o u n ~ s m o d u l u s a n d V i c ke r s h a r d n e s s v a l u es c o m b i n edw i t h

a re l a t i ve l y l ow sur fa c e roughne ss va l ue woul d be t he

chara te r i s t i c prope r t ies of the pos te r ior com posi te of choice .

Onl y t h re e c ompos i t e s a pprox i ma t e t h i s c onc e p t , na me l y

Adap t ic I I, P-50 APC, and Z-100 ( indica ted by sma l l f il l ed

diamond s) . Al l thre e com posi tes a re U l ta f ine Compact -Fi l l ed

Composi tes .

The p a ra m e t e r s d i sp la ye d in F i g . 10 ma y be o f he l p i n

ca tegoriz ing newly deve loped mater ia l s . Check ing the int r in-

s ic su r fa c e roughne ss a nd Young s mod ul us o f t he se ne w

composi tes wi l l cons iderably he lp to rank these mater ia l s

a mon g c omp e t i ng p roduc t s . The Vi c ke rs ha rd ne ss a dd i ti on-

a l ly g i ve s a n i de a a bou t t he me c ha n i c a l p rope r t ie s o f the

ma ter ia l inv es t iga ted. How ever , c linica l s tudies on compos-

i tes wi l l have to conf i rm the i r in vi tro performance .

The goa l i n r e s t o ra ti ve d e n t i s t ry shou l d be to m a ke h i gh l y

we a r - re s i s t a n t oc c l ud ing sur fa ce s t ha t do no t w e a r oppo s i ng

s t ruc tures .

R E F E R E N C E S

Albers HF (1985) . Res in sys tems.

In: Too th colored restora t ives.

Sev enth ed i t ion. Cota t i : Al to

Books, 21-62.

Am erican Socie ty for Tes t ing an d M ater ia l s (1984). Designa-

t i on E 384-84 : S t a nda rd t e s t me t hod fo r mi c roha rdne ss o f

ma t e r i a l s . In : P r i e m on R A, e d i to r . Ann ua l book of ASTM

Stand ards . Sec t ion 03.03. Eas ton: A me rican Socie ty for

Test ing an d M ater ia ls , 356-377.

Ame ye C , La m bre c h t s P , Va nh e r l e G (1981) . C onve nt i ona l

an d m icrofi l led com posi te resins. I . Color stabi l i ty and

ma rg i na l a da p t a t ion . J Pros thet Dent 46:623-630.

Atm adja G and Bry ant RW (1990). Some fac tors inf luenc ing

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