BIOGLAZES ADHESION TO METALS

HAL Id: jpa-00225513

https://hal.archives-ouvertes.fr/jpa-00225513

Submitted on 1 Jan 1986

HAL is a multi-disciplinary open access archive for the deposit and dissemination of sci- entific research documents, whether they are pub- lished or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.

L’archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d’enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

BIOGLAZES ADHESION TO METALS

A. Ravaglioli, A. Krajewski, P. Ponti, R. Valmori, S. Contoli

To cite this version:

A. Ravaglioli, A. Krajewski, P. Ponti, R. Valmori, S. Contoli. BIOGLAZES ADHESION TO MET- ALS. Journal de Physique Colloques, 1986, 47 (C1), pp.C1-769-C1-774. �10.1051/jphyscol:19861117�.

�jpa-00225513�

JOURNAL D E PHYSIQUE

Colloque c l , suppl6ment au n02, Tome 47, fhvrier 1986 page cl-769

BIOGLAZES ADHESION TO METALS

A. RAVAGLIOLI, A. KRAJEWSKI, P. PONTI, R. VALMORI and S. CONTOLI*

C.N.R., Research Institute for Ceramics Technology, Via Granarolo 64, I-48018 Faenza, Italy

"civil Hospital of Faenza, Horthopedy and Traumatology Div., U.S.L. n o 3 7 , 1-48018 Faenza, Italy

R6sunie - Le b u t de ce t r a v a i l c o n s i s t e en un e s s a i de d e p 6 t s u r une p r o t h 6 s e --

m e t a l l i q u e a f i n d ' e n a m e l i o r e r l a t o l e r a n c e p a r l e c o r p s humain en vue d ' i m - p l a n t a t i o n i n t e r n e s . Les parametres c o n s i d e r e s s o n t : l a c o n ~ p o s i t i o n de base, l e s dgents dopants a j o u t e s e t p r i n c i p a l e m e n t l a l i a i s o n e n t r e l

l e m6tal s u p p o r t e t l e v e r r e b i o a c t i f .

A b s t r a c t - The purpose o f t h i s s t u d y c o n s i s t s o f an a t t e m p t t o c o a t a m e t a l p r o s t h e s i s so t h a t i t can be b e s t accepted b y t h e human body i n case o f i n - t e r n a l i m p l a n t a t i o n s . B a s i c c o m p o s i t i o n , doping agents added and above a l l t h e l i n k i n g among bone, metal and g l a s s t h r o u g h o p t i c a l and SEM a n a l y s e s a r e some o f t h e parameters t a k e n i n t o account.

I - INTRODUCTION

I n i t i a l s t u d i e s on t h e s u i t a b i l i t y o f c o a t i n g m e t a l p r o s t h e s i s w i t h b i o a c t i v e substances have been s u f f i c i e n t l y s u c c e s s f u l so as t o encourage f u r t h e r r e s e a r - ches i n t h i s f i e l d . What r e p o r t e d i s a p a r t o f a more g e n e r a l problem o f t h e p r o s t h e s i s c o a t i n g t o a v o i d t h e d i r e c t c o n t a c t between m e t a l a l l o y and husran t i s s u e . I n t h e p r e v i o u s years, c o a t i n g were t r i e d w i t h plasma sprayed A1 O3 and ZrO .Main draw back o f such c o a t i n g s i s due t o t h e i n t r i n s i c h i g h b r i t Z l e n e s s o f $he c o v e r i n g m a t e r i a l s and t o t h e g r e a t l y d i f f e r e n t e l a s t i c p r o p e r t i e s charac- t e r i z i n g t h e t w o m a t e r i a l s on c o n t a c t . Not a l l t h e m a t e r i a l s a r e s u i t a b l e f o r t h e purpose, s i n c e t h e t i s s u e s g i v e r i s e , towards f o r e i g n m a t e r i a l s , t o a s t r o n g and d e c e i t f u l chemical a t t a c k ; such a c t i v i t y o f b i o c h e m i c a l n a t u r e t a k e s p l a c e a1 so t h r o u g h r e a c t i o n s o f metal - o r g a n i c complexations. Among t h e p o s s i b l e c o a t i n g m a t e r i a l s , we t a k e i n t o account t h e s o - c a l l e d " b i o a c t i v e " ones which can g i v e r i s e t o an osteogenesis and a m i n e r a l i n g r o w t h a l l around: t h e h y d r o x y l a p a t i t e and t h e b i o a c t i v e g l a s s e s . While t h e f o r m e r shows b i g problems o f c o m p a t i b i l i t y i n metal adhesion, t h e l a t t e r can be c o n t r o l l e d , t o a c e r t a i n e x t e n t , i n i t s a d h e s i v i t y by means o f a s u i t a b l e doping / l - 3 / .

The atomic s p e c i e s f o r m i n g t h e a l l o y t o be c o a t e d (expressed i n atomic e q u i v a l e n t s ) must be p r e s e n t i n a p p r o x i m a t e l y t h e same r e l a t i v e r a t i o amounts as c a t i o n s i n t h e f u s e d g l a s s . /l/ Such r a t i o - w i t h i n a c e r t a i n range o f t o l e r a n c e - may De

Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/jphyscol:19861117

Cl-770 JOURNAL DE PHYSIQUE

checked by XES a n a l y s i s drawn from t h e metal surface o f t h e support and on t h e e x t e r n a l surface o f t h e b i o a c t i v e glass c o a t i n g (Fig.1 e.g.coating by AKRA 15).

On t h e b i o a c t i v e glass one f r a c t i o n o f mineral bone increases as t i m e goes by w i t h a c o n t r o l l e d p a r t i a l r e a d s o r p t i o n o f t h e glass l a y e r t i l l a thickness l e s s than h a l f a m i l l i m e t e r .

I 1 - GLASS - TO - METAL JOINT

Many o f t h e h i g h temperature c o a t i n g made u n t i l 1 now are n o t acceptable because t h e u n s a t i s f a c t o r y r e p r o d u c i b i l i t y o f t h e r e s u l t s . The g r e a t e s t problem i s t h a t

Fig. 1 - X-ray p h o t o e l e c t r o n i c spectra (XES) on t h e e x t e r n a l surface o f t h e b i o a c t i - ve g l a s s c o a t i n g ( l e f t ) and on t h e uncoated metal surface ( r i g h t ) .

o f del amination o f some p a r t s o f t h e coating, e s p e c i a l l y d u r i n g t h e c o o l i n g process. We a t t r i o u t e a l l t h i s t o t h e present methods o f manufacturing based on o p e r a t i v e steps c a r r i e d out by hand. This i n c l u d e , as main steps, a p r e o x i d a t i v e heating o f t h e m e t a l l i c support i n t o a k i l n , a f a s t d i p p i n g o f t h i s i n t o t h e melted D i o a c t i v e glass and a very slow c o o l i n g i n t o c o n t r o l l e d heater. I n order t o recover a t l e a s t a p a r t o f t h e 60% unsuccessful pieces, we t r i e d t o recover t h e f a i l e d pieces by a second d i p p i n g i n t o t h e same g l a s s melt. I t was found t h a t by t h i s treatment some zones o f t h e c o a t i n g transformed themselves from glass t o glass-ceramic system. These transformed zones were o p t i c a l l y darker and c o n t a i n m i c r o c r y s t a l s o f Na CaSiO 0 and NadCaSi 0 as i t may be deduced

2 3 8.

from numbered peaks o f t h e X-ray d i f f r a c t ? o n B p a t t e r n o$ %;g.2. This glass ceramic seems t o adhere s t r o n g l y t o t h e metal surface. H o w e v e r , t h i s t w i c e d i p p i n g technique, even i f i t shows a 10% o f recovery o f t h e f a i l e d sample, i s n o t y e t a s u i t a b l e tech- nique t o warrant standard c h a r a c t e r i s t i c o f obtained products, and i t was n o t

F i g . 2 - X-ray d i f f r a c t i o n p a t t e r n s o f complete glassy zone o f b i o c o a t i n g (A) and

glass ceramizes zone (B) o f t h e same sample o f AISI 316L covered w i t h an about 0.5

mm b i o c o a t i n g l ayer.

F i g . 3 - An i n t e r e s t i n g bone ingrowth upon b i o a c t i v e glass i n t h e e x t e r n a l p a r t o f t h e prosthesis, near t h e head o f t h e f i x i n g screw (420x1. The b i o a c t i v e c o a t i n g i s t h e AKRA 15 glass.

< a ) metal body; ( b ) g l a s s l a y e r ; ( c ) bone ingrowth; ( d ) head o f f i x i n g screw.

- t i s s u e and c a l c i f i c a t i o n ingrowth d i r e c t i o n

- - - W

d i r e c t i o n o f d i f f u s i o n o f digested glass zones containing o r i g i n a l o r diffused glass

(-1 dense zones a t t r i b u t e d t o col lagenic ingrowth

F i g . 4 - A schematic r e p r o d u c t i o n o f photo o f Fig. 3, where t h e various d e t a i l s are emphasized. Ie i s d i s p l a y e d t h e supposed mechanism o f glass e r o s i o n by biochemical a t t a c k o f c o a t i n g l a y e r , having a t t r i b u t e d t h e c o n s t i t u t i o n o f observed denser zones by mi crop.robe aid.

t

o r i g i n a l average thickness o f t h e c o a t i n g g l a s s l a y e r b e f o r e i m p l a n t a t i o n .

c l - 7 7 2 JOURNAL DE PHYSIQUE

F i g .

-

p h o t o o f a z o n e b e t - F i g . 6 - ^{E D X} o f S i d i s t r i b u t i o n i n w e e n t h e m e t a l l i c p r o s t h e s i s a n d t h e a r e a o f F i g .

p r e s e n t a r o u n d t h e b o n e . a : b o n e ; h : g l a s s : c : t h e m e t a l b o u n d a r y , p a r t i c u l a r l y m e t a l l i c b o d y ( 2 0 ~ ) . t o w a r d s c o r t i c a l h o n e ( 2 0 ~ ) .

F i g . 7 - ^{S E M} p h o t o o f a p o r t i o n F i g . 8 - E D X o f P d i s t r i b u t i o n i n r e l a t i v e t o t h e l e f t p a r t , s h o w n t h e a r e a o f F i g . : ( 2 0 x 1 , i d e n t i = i n F i g .

( 2 0 x 1 . c a l t o t h e Ca o n e . T h e s m a l l b l a c k

z o n e s s h o w t o b e f i l l e d b y S i .

t a k e n i n t o c o n s i d e r a t i o n f o r o u r s c i e n t i f i c t e s t s . Which was made on s u c c e s s f u l y covered p i e c e s b y t h e one d i p p i n g method. P r o b a b l y g r e a t e r he1 p can be o b t a i n e d be a complete a u t o m a t i z e d d e v i c e t o s t r o n g l y improve s t a n d a r d i z a t i o n o f manufactured p i e c e s by e l i m i n a t i n g manual procedures.

111 - EXPERIMENTALS AND RESULT

R e l a t i v e t o t h e o p t i c a l photoes, we r e p o r t o n l y t h e one o f F i g . 3 w i t h a d e t a i l o f a t i s s u e i n g r o w t h on a covered sample w i t h AKRA 15 b i o a c t i v e g l a s s i n t h e area near t h e screw. A schematic drawn f o r h e l p i n g t h e r e a d e r i n t h e u n d e r s t a n d i n g i s t h a t r e p o r t e d i n F i g . 4 . w h i c h shows t h e d i r e c t i o n s o f m i n e r a l t i s s u e i n g r o w t h . I n t h i s case a m i n e r a l f r a c t i o n occurs, whereas f o r AKRA 17 and AKRA 18 ones i t d i d n o t .

Table 1 - Composition o f t h e c i t e d b i o a c t i v e g l a s s systems.

Oxides W In g) anp posit tons

AKRA 15

AKRA 17

AKRA l 8

Looking a t samples c o n c e r n i n g AKRA 17 and AKRA 18 b y o p t i c a l m i c r o s c o p e , s i g n i f i c a n t amounts o f m i n e r a l compounds d i d non appear whereas a v e r y b i g i n g r o w t h o f bone c a l l u s d i d . Contemporary t h e g1 ass l a y e r s o f such t w o composi t i o n s appeared a1 t e r e d i n t h e i r n a t u r e f o r g e n e r a l d e c o l o r a t i o n and f o r b i g l a y e r e d c r a c k i n g , due t o a wide e v i d e n t i o n s exchange. The SEM-EDX photoes show t h e permanence o f t h e g l a s s between bone and m e t a l f o r t h e AKRA 17 and AKRA 18 c o m p o s i t i o n s ( F i g . 5 and 6 ) . F o r AKRA 15 c o m p o s i t i o n a g e n e r a l g l a s s r e a d s o r p t i o n w i t h s u b s t i t u t i o n of m i n e r a l bone was observed by o p t i c a l rnicroscopy. T h i s i s confirmed by a n o t r e p o r t e d SEM-EDX p h o t o r e l a t i v e t o S i d i s t r i b u t i o n . I n F i g . 7 a SEM p h o t o o f t h e same sample o f F i g . 3 i s shown. The EDX a n a l y s i s o f P d i s t r i b u t i o n i n t h e a r e a ( F i g . 8 ) shows a b e g i n n i n g o f m i n e r a l i z a t i o n a l l around t h e m e t a l l i c sample.

T h i s d i s t r i b u t i o n i s i d e n t i c a l t o t h e Ca one ( p h o t o o b v i o u s l y o m i t t e d ) . On t h e o t h e r hand t h i s i s n o t s u r p r i s i n g , because w e l l known i s t h e t r a n s f o r m a t i o n o f t h e t h i n s u r f a c e a l l a y e r o f b i o a c t i v e g l a s s i n t o s i l i c a g e l covered by i n g r o w i n g l a y e r s o f h y d r o x i l a p a t i t e t h a t r e p r e s e n t s t h e m i n e r a l p a r t o f t h e bone 141.

---

I V - CONCLUSIONS

---_______----_--_---,

---,---

---

-base-:aneo!!!o? ---,-_---A-

'"2

45

---

---

The p r e s e n t work c o n f i r m s t h e v a l i d i t y o f p r o d u c t i o n a t t e m p t s o f m e t a l l i c p r o t h e s e s c o a t e d b y b i o a c t i v e g l a s s . The b i o a c t i v e g l a s s a c t s as an autocementing substance l i n k i n g t h e bone t o t h e p r o s t h e s i s /l ,2/, T h i s a v o i d s t h e r e c o u r s e o f a c r y - l i c cement s i n c e t h e g l a s s c r e a t e s t h e c l o s e l i n k i n g w i t h t h e bone t i s s u e . Some problems, o c c u r r i n g i n making c o a t e d prostheses, were en~phasi zed t h a t s t i l l b r i n g t o a h i g h number o f f a i l u r e s . On t h e o t h e r hand such problems a r e l i k e l y t o be s o l v e d b y u s i n g d e v i c e s s u i t a b l e f o r w o r k i n g a c c o r d i n g t o s p e c i f i c standards, a v o i d i n g manual procedures. However, i n i t s autocementing r o l e , t h e b i o a c t i v e g l a s s i s p a r t i a l l y readsorbed and c o n s e q u e n t l y t h e p o s s i b l e f r a c t u r e d u r i n g t h e t i m e i n i m p l a n t e d p r o s t h e s e s i s l e s s i m p o r t a n t . I t i s o b v i o u s l y d e c i s i v e t h a t , a t t h e i n i t i a l stage o f i m p l a n t a t i o n , t h e b i o a c t i v e g l a s s has a c l o s e adherence w i t h t h e metal, i n p a r t i c u l a r t o e n a b l e t h e bone t o i n c r e a s e s l o w l y as t i m e goes by.

24.5

24.5

24.5

---i---

---

---

0.1

---

A1203

2.0

2.0

---

Na20

24.5

24.5

24.5

B203 - - - , - - -

---

---

0,6

---

' ~ O S

6

6

6

Cr20g

---

0.6

0.2

0.2

Co20j

--- ---

0, 1 NiO

---

1.0

--- ---

0.2

---i.*---

Fe203

---

6.0

2.4

8.0

Ta205

1.0

0.6

- - -

_______-________-__---.---

Sb203

---

0.1

- - -

Ls203

0.5

--- ---

_______

Cl-774 JOURNAL DE PHYSIQUE

AKNOWLEDGEMEIITS: t h e Authors are indebted t o Gerardi Stefano (IRST-Trento Univ.) and w i t h Faenza Lions Club.

REFERENCES

/1/ Krajewski, A. , R a v a g l i o l i , A. ,De Portu, G. and Visani R., Arner.Ceram.Soc.

5 (1985j, 679-683.

- /2/ R a v a g l i o l i , A. and Krajewski , A., Ceramica Informazione 10 (1983) 583-591.

/3/ Azzoni, G.B., Del Nero, G., Krajewski, A. and ~ a v a ~ l i o l i , A., Mat.Sci. - 19 ( 1984 ) 3620-3625.

/4/ Ogino, N. and Hench, L.L., J. non Cryst. S o l i d s 38 & 39 (1980) 673-678.