1. FTIR and NMR of Hydroxyapatite
incorporation with Heat Cured Acrylic
Amer A. Taqa Nadira A.
Zena J.
University of Mosul, College
of Dentistry

2. Acrylic Resin Denture Base Material History
In 1937, poly methylmethacrylate (PMMA) was
introduced and used widely as a denture base
material. PMMA provided enhanced physical
and esthetic properties; in addition, it was
readily available, inexpensive and relatively
eases of use, and reliance on simple processing
equipment (Nejatian et al., 2006).
REVEW OF LITERATURE :

3. The hydroxyapatite (Ca10(PO4)6(OH)2) has
been widely used as a bone substitute, taking
into account its biocompatibility, as its
mineral components are similar to those of
the bones and teeth of the human body.
Synthetic hydroxyapatite is an important
biomaterial used in many medicine
applications in bulk, as a coating, or as a
component of a composite .

4. Pure Hydroxyapatite powder is white.
Naturally occurring apatites can, however,
also have brown, yellow, or green
colorations, comparable to the
discolorations of dental fluorosis. Up to
50% of bone is made up of a modified
form of the inorganic mineral
Hydroxyapatite known as bone mineral
(Junqueira et al., 2003).
Hydroxyapatite (HA) :
REVEW OF LITERATURE

5. Relining
Relining is the process of adding some
materials to the tissue side of denture to
fill the space between the tissue and the
denture base ( Robert, 1985; Levin and
Richared, 2002).

6. Aims of Study:
1. incorporation of synthetic Hydroxyapatite
(2%,5%) extracted from eggshells then study
FTIR, HNMR spectra of heat cured acrylic
resin denture base mixed or relined denture
base.
2. Biocompatibility of denture synthetic
Hydroxyapatite on rabbits.
3. Other physical and mechanical properties
also study.

7. MATERIALS AND METHODS

8. Materials Used in the preparation samples of this Study
No. Material Manufacture
1. Dental stone. Elite stone (Zehrmack)/
2. Heat cured acrylic resin.
RESPAL NF(RESINA
PALATIA CALDO/Italy)
3. Hydroxyapatite Prepared from egg shell
4. Separating medium. Isodent
5. Formaldehyde 3A MEDES company,
6. Hard elastic foils 3mm 2.5mm 1.5mm Rotex medica Gmbh
7. Ketamine hydrochloride general anasthesia Tiergesudheit Gmbh
8. Xylazine(sedative analgesic) Horsterweg 26A
9. Absolute Alcohol BDH Company
10 Pure vasline Comercial available

9. Total Samples 171 divided according to the test for
each subgroup 5 Samples
5% HA gp2% HA gpControl gp HCAR
HCAR
Relined with
HCAR with
5% HA
Samples 5%
HCAR
mixed 5%
HA
Samples
HCAR
relined with
HCAR With
2% HA
Samples
HCAR
Mixed
with2% HA
Samples
Measurement properties
indentation hardness , transverse strength , water sorption and solubility,
tensile strength, dimensional accuracy, residual monomer , FTIR , and
biocompatibility and microscopical examination of Prepared polymer .
HCAR : Heat Cured acrylic resin.
HA : Hydroxyapatite

10. Samples preparation with and without additive (HA):
Polymer and monomer of heat cured acrylic resin
have been mixed in ratio (2.2 gm:1ml by volume),
(according to the manufacturer instructions).
While the experimental groups of heat cured acrylic
resin with additive have been prepared by mixing
powder (polymer) (22gm polymer with 0.5gm
hydroxyapatite for 2% and 8.8gm polymer with 0.5gm
hydroxyapatite for 5%)
A B
Method

11. Relining sample preparation:
The samples were prepared by placing hard elastic foil
with 1.8mm thickness for indentation hardness and
residual monomer test, 1.5 mm for transverse strength,
dimensional accuracy test and 2mm for water sorption
and solubility test to the desired length and width
specified for each test (Hasan, 2002).
Method

12. Relined part of denture base was prepared
mixed with hydroxyapatite
Method
A
B C D
E
F

13. FTIR Test:
Samples prepared with dimension 10x4x4(±0.03)mm (Urban et al.,
2007) samples were removed from water and dried in air and then
scraped using a sharp, clean and sterile wax knife to obtain powder
of the polymerized samples.
The FTIR spectra was carried by Tensor 27 FTIR spectrophotometer
Method

14.  H1NMR spectra was done in Chemistry
Department, Colorado state University,
USA using CIF-MR 400-Vnmrs400 in
CDCl3 solvent.

15. Biocompatibility test
2mm width
5mmlength
Four local bred male rabbits, 4-6 months
old with an average weight 1.250-1.350 Kg
were used and the animals were housed in
animal house prepared for this purpose,
the animals were diet of vegetables 2 times
daily (AL-Saigh, 2007).
Method

16. The anesthetized
animal was laid on
it is abdomen on
the operation
board. The fur was
shaved in 2 areas
of the rabbits
mandible one on
right side and other
on the left
Method

17. (the first rabbit in the
right side the control
sample is placed and on
the left side the
2%hydroxyapetite
sample is placed and the
second rabbit on the
right side the control
sample is placed and on
left side the 5%
hydroxyapetite sample is
placed) (Jones et al.,
1978).
Method

18. RESULTS

19. FTIR test :
In the IR charts two important absorbance
peaks in poly metheylmethacrylate appeared (the
absorbance of the C=C band from the methacrylate
group which appear around 1683 cm-1

20.  and the absorbance peak of the C=O
from the ester group appear around
1733 cm-1) and some important bands
for HA 3446 cm-1 for OH stretching,
992cm-1(V1PO4),601 and 571cm-1 for
(V 4 PO4) .

21. Control sample
C=O
C=C

22. Acrylic with 2% HA
C=CC=O
νOH
ν1PO4
ν4PO4
ν4PO4

23. Arylic with 5% HA
C=CC=O
ν1PO4
ν1PO4
ν4PO4
νOH

24.  The results showed there is now
reaction between Additive HA (2%
and 5%) and poly methyl methacrylate
after polymerization also the HA still
incorporated with PMMA.

25.  1H NMR spectra show two highly intense
broad peaks centered at 0.7 and 5.6 ppm,
respectively. The NMR peak near 1 ppm is
due to hydroxyl group in HA,(Yesinowski
1987).

26. The observed NMR peak around 5.25
ppm indicates surface-adsorbed water
in the nanocrystalline of HA. Such
kinds of results are well known in the
literature for HA (Miquel 1990).

27. -COOCH3
-CH2-C-
-C-CH3
PMMA
OH of HA

28. Biocompatibility Test:
Biocompatibility test shown new bone formation in the rabbits after 30 days of
implantation for both 2% and 5% Hydroxyapatite samples according to
decision of intra examiner specialist of oral pahology
A.Controlled bone (without additives)
C. new bone in sample with(5%Hydroxyapatite)
B. new bone in sample with(2% Hydroxyapatite)
Blood vesselOsteocyte
Osteocyte
Blood vessel

29. The histopathological examination showed
more new bone trabeculae formation in the
(HA) than normal bone, a finding that
agrees with earlier study ( AL-Khafaji,
2001) which showed active bone formation
started after one month of implantation.
This finding may be due to more late
neovascularization and release of calcium
from the graft into surrounding tissue.

30. Conclusions:
The present study comes up with the
following conclusions:

31.  In FTIR and H1NMR spectra test
showed that the addition of 2% and
/or 5% hydroxyapatite to heat cured
acrylic resin denture base material
resulting a homogenous mixture,
without chemical reaction.

32.  Using Hydroxyapatite as additive
for denture lining show
biocompatibility of the material
and enhance new bone formation.