Osteology Venedig Mai 98_Poster Diffraktometrie HA_TCP

X-Ray Diffraction of Bone Regeneration Materials
Weibrich, G., Gnoth, S. -H., Trettin, R.*, Werner, H.-D.* , Wagner. W.
Clinic for Oral- and Maxillofacial surgery (Director: Univ. Prof. Dr. Dr. W. Wagner), Augustusplatz 2, 55118 Mainz, Germany
* Department for Mineralogy
Introduction:
diffractometry
The Bragg- equation (fig. 3) describes
intensity and a small basis of the peaks
(RDX) is a validated routine procedure
Powder
the angle of incidence and reflection. The
is correlated to pure materials.
in mineralogy (1, 2) to investigate the
materials
structure and composition of crystallized
measurement of the specific intensity
are
characterized
by
the
60
50
Perioglas (Bioglas)
curves (fig. 4). The typical localization, a
hydroxyapatite (HA) and tricalcium-
high
counts/sec
materials. The crystalline structure of
Biogran (Bioglas)
40
30
20
10
0
10
phosphate
(TCP)
used
as
11
12
13
14
15
16
17
bone
18
19
20
21
22
23
24
25
26
27
28
Theta [degree]
n * Lamda = 2d * sin (Theta)
regeneration materials influences their
Fig. 3: The Bragg equation describes the correlation
between the wave length of the X-rays lambda, the
crystalline structure and the theta angle.
physical properties. Different velocity of
the solution of synthetic and biological
500
450
HA seems to be correlated to different
beta-TCP (Cerasorb)
counts/sec.
400
350
results in RDX analysis (4). As far as is
known there are no comparative (!) RDX
alpha-TCP (Biobase)
HA (Endobone)
300
250
200
150
100
50
0
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
analyses for the TCP -materials in clinical
Theta [degree]
use.
Fig. 4: Cristalline, chemically similar or identical
materials
can
be
differentiated
by
powder
diffraktometrie. In Fig. 4 the intensity curves of
diffenerent materialgroups are shown – hydroxy apatite
(green), alpha-TCP (blue), beta-TCP (red). Typical peaks
are marked with an arrow.
Goals: The dimension and quality of
crystallization
of
several
bone
Results: The results are listed in table 2.
replacement materials are analyzed by Xray diffraction.
Material and methods : The analyzed
materials are listed in table 1.
Group Origin
Specimenname
_______________________________________________
1 HA
a. synthetic
Ceros80
Merck*
b. bovine
Endobone
Merck
bovine
Bio Oss
Geistlich
c. phytotroph Algipore
Friatec
2 TCP
synthetic
Ceros82
Merck*
synthetic
Biobase
Sulzer-Calcitek
synthetic
Cerasob
Curasan
3 Bioglass
synthetic
PerioGlas
Dumex
synthetic
Biogran
Orthovita
*The material ist not supplied under this name and by this supplier.
Tab. 1 The investigated materials were divided in three
groups: HA, TCP and Bioglass.
X-rays hit the crystal structure of the
materials and are reflected in a defined
angle (fig. 1, 2).
Supplier
Specimen- Composition [%] Amorphous Kristallisation
name
HA aTCP bTCP
Portion
[high/low]
1 HA
Ceros80
>95 0
0
<5
+
Endobone >95 0
0
<5
+
BioOss
>95 0
0
<5
Algipore
80
0
0
<5
20% Ca-Hydroxid
2 TCP
Ceros82
30
0
70
<5
+
Biobase
0
>95 0
<5
+
Cerasorb
<<5 0
>95
<5
+
3 Bioglas
Perioglas
100% glass no
Biogran
100% glass no
Tab. 2 Composition of bone regeneration materials,
evaluated by powder diffractometry.
The HA-products with the exception of
Algipore seem to be pure. Ceros80 and
Endobone (shown by a narrow basis of
the intensity peak: fig. 5.) were the only
ones
which
seem
to
be
totally
crystallized.
600
550
500
Ceros80 (HA)
counts/sec
450
Endobone (HA)
400
BioOss (HA)
350
Algipore (80% HA, 20% CaOH)
300
250
200
150
100
50
0
10
Fig. 1: Experimentell arrangement of the used powder
diffraktometer (1)
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Theta [degree]
Fig. 5: Powder diffractometry of the HA materials
The TCP -products Biobase and Cerasorb
are nearly pure, where as Ceros82 seems
to contain a mixture of 30 % HA and 70
% beta-TCP. All TCPs show a high
Fig. 2: The reflection of the X-rays an the structure of the
crystal has an angle of 2 Theta
crystallization.
A G , D-68222 Mannheim, Sulzer-Calcitek GmbH, D-79001
counts/sec
450
Freiburg.
400
Biobase (a-TCP)
350
Cerasorb(b-TCP)
300
Ceros82 (70%b-TCP, 30% HA)
250
200
150
100
50
0
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
Theta [degree]
Fig 6: The localization and the intensity of the peaks seems
to show nearly pure TCP products for Biobase und Cerasorb.
Ceros82 seems to consist of 30% hydroxyapatite.
The bioactive glasses did not show
crystalline
structures.
The
relative
incline in intensity between 14 and 19
degree Theta is presumable a correlation
of minimal structural components (fig 7).
Fig. 7: Both investigated bioglasses showed no intensities,
which can be correlated to crystallized structures.
Discussion: There are many possible
causes
for
crystallization
inhomogeneous
of
the
investigated
materials, as composit of different foreign
ions,
extremely
abnormal
sma ll
(deficient)
crystals
apatites.
or
The
meaning for biological behavior is
mostly unknown. Best and Bonefeld
demonstrated in 1994 by RDX-analysis
of three HA materials for the Merck
material corresponding results to our
study for Endobone (3). Sy nthetic
materials can reduce the risk of infection.
Summary:
We
found
differences
between the examined materials, the
meaning for the biological behavior is
unclear.
Further
investigations
are
neccesary to correlate the characteristics
of the materials to the clinical outcome.
Because of the risk of infection, bovine
materials is still under discussion. Their
indications
should
be
considered
carefully.
Literature:
1. Harald Krischner, Brigitte Koppelhuber-Bitschnau.
Röntgenstrukturanalyse und Rietveldmethode . 5. Aufl.
1994, Vieweg Verlag, Braunschweig, Wiesbaden
2. Rudolf
Allmann.
Röntgen-Pulver-Diffraktometrie.,
Clausthaler Thektonische Hefte. Sven von Loga, Köln,
1994
3. Best, S., Bonfield, W. Processing behaviour of
hydroxyapatite powders with contrasting morph ology,
Journal of Materials Science: Materials in Medicine
5(1994) 516-521)
4. Abdel-Fattah, WI; El-Sayed, AM; Ali, FM; Beheri, HH.
(1994) Serum-hydroxylapatite interaction in vitro.
Biomaterials. Juli 1994; 15 (9): 643-9.
Acknowledgements:
Our investigation was financially supported by Geistlich
Biomaterials, GEWO GmbH, D-76487 Baden-Baden, Friatec