J. Nihon
Univ.
Sch.
Dent.,
Vol.
34. 178-182,
Investigation
of
Mahir
words:
Surface
Corrosion
GUNDAY
(Received
Key
1992
and
14 October
high-copper
Nimet
1991
amalgam,
in
and
Amalgam
GENCOGLU
accepted
corrosion,
5 March
1992)
conventional
amalgam,
SEM
Abstract In
this
study,
tional
and
detect
surface
later
surface
high-
investigated
after
by
specimens
and
showed
less
in
holes
than
The
for
in
was at
specimens specimens
saliva
greatest
surface
opening
corrosion
polished
artificial
was
The
deep
and
investigated.
Corrosion
specimens.
visible
carved
was
immersion
SEM.
amalgam
particles
of
amalgams
corrosion
conventional the
corrosion
copper
very
the
48
h
conven-
studied
or
with
and carved
the
contours
High-copper
amalgam
to
1 year,
1-year-immersed
rough
surface.
conventional
of were
of
amalgam
specimens.
Introduction As
well
material
as
with
subject
to
is
a
also
being
unlike
low
tensile
a
corrosion,
of
structure
The
in
of
of
composition
respect
in
the
present
amalgam
of
the
due
with to
Two
types
(ANA The
of
alloys
mm
in
starting after
30
to
placed 37•Ž
in and
a
the
an
Corrosion
of
surface
is
but
the
oral
planus actual
in
amalgam
into
the
of
surface
the
chemical has
deterioration,
species
also
time,
into
lichen
but
metallic
It with
ions
and
fracture, of
was
to
clarify the
mixed
beakers solutions
were
been micro-
surrounding
the
effect
of
nature surface
corrosion
preparation
on
the
used:
Four
(600
(Lumicon)
made manually
in as in
accordance
plugs a plastic
of
each
alloy
were
made,
and
the
others
were
polished
saliva every
after (pH:
polishing,
6.65)[8].
The
the beakers
long
mold
carved,
Immediately
the
with
8 mm
specimens
grit).
and
I).
mercury
were
performed
were
renewed
conventional (Table
with
them
artificial
were
one
content
amalgams was
of
in
Methods
mechanically The
trituration. two
and
high-copper
Condensation
wheel glass
allergy
metals [3].
investigate
alloy
with
condensation,
silicon-carbide
metallic
deposit,
marginal
study
and
amalgam
were
s after
cause
integrity
vitro[1,4-7].
instructions.
diameter.
of
is a brittle
toughness.
surfaces.
2000)
manufacturer's
release
release
amalgam or
structural
surface
Materials
other
to
a
appearance, ductility
its
may
and
and
in
little
degrades
merely
amalgam
vivo
purpose types
only
elements with
corroded
both
two
not
non-metallic
of
milieu
not
and
products is
extensively
structure
concern
Corrosion
studied
of
which
Corrosion
mouth[2].
tooth
strength
biocompatibility
environment[1].
reaction
the
the and
for and
were
s,
24
h
with
specimens
2
60
a
were stored
at
month.
Department of Conservative Dentistry and Endodontics, Faculty of Dentistry, Marmara University, TURKEY To whom all correspondence should be addressed.. Mahir GUNDA Y, c/o Nimet Gencoglu, Anafartalar sok Fulya ap 3/ 1, Yesilkoy, Istanbul, TURKEY.
179
Table
I
Two amalgam specimens (the carved and the polished) were immersed for a period of 48 h and the other two were immersed for 1 year. Corrosion of the surface of the specimens was studied using a SEM (JEOL-100C). Results Conventional Amalgam The surface corrosion of 48-h-immersed carved and polished specimens is presented in Fig. 1-A, B. The surface was rough with the contours of the particles
1A
1B
1C Fig.
1
The carved
surface (C),
of
48-h-immersed
polished
(D)
carved specimens
1D (A), of
polished
conventional
(B)
specimens
amalgam
and (•~500)
1-year-immersed
180
Fig.
2
The carved
surface (C),
of 48-h-immersed polished
(D)
2A
2B
2C
2D
carved specimens
(A), of
polished
high-copper
(B)
specimens
amalgam
and
1-year-immersed
(•~500)
visible on the carved specimen. Although smoother in appearance, small pores were seen on the polished specimen. The surface of a 1-year-immersed carved specimen is shown in Fig. 1-C. Not only a rough surface but also spaces around the particles and deep holes were seen in the carved specimen. On the other hand, pits and small cracks were seen in the polished surface specimen (Fig. 1-D). High-Copper Amalgam The surfaces of 48-h-immersed specimens
are shown
in Fig. 2-A, B. The
polished surface was smoother than the carved surface on the specimens. The surfaces of 1-year-immersed specimens are shown on Fig. 2-C,D. Rough surface of the polished specimen and different sizes of particles were seen in the same sample. Holes and cracks were seen in the carved surface specimen. Discussion The carved surface of conventional amalgam was rougher than the polished surface in 48-h-immersed specimens. Although the polished surface was smooth, pits and pores were also seen on the surface. Besides porosity,
large spaces between
181
the
particles
and
amalgam.
holes
Studies
amalgam
is the
surface
weakest
contains
JORGENSEN
Sn
AND
dominant,
immersed cause
also
small
propagating saline
the
than
and
weeks,
of
and
surfaces
AND
ODEN[7] layer
Cl.
The
region
In
our
study,
surface the
most
not of
most
only 1-year-
common
enlarging
the
pit
and
investigated
amalgam
soaked
products
containing
corrosion
pores
and
polished
the
was
of of
study, of
the
amalgam,
phases.
phase
our
Possibly
of
a
because
on
specimens.
found
specimens.
carved
seen
In
corrosive
the ƒÁ2
the ƒÁ2
pores.
were
The
from of
and
disintegration
and
Sn
cracks
conventional
corrosion[9,10].
corrosion
amalgam
further
to
conventional
of
released
voids
of
(tin-mercury)
are
that
MOBERG
35 of
surface
sion
which
indicated
pores
specimens
phase phase
Sn-containing
process. for
the ƒÁ2
ions,
also
was
concentrations
polished
Zn
conventional
solution
high
susceptible
most
in
pores
1-year-immersed
and
small
polished of
in that
and
resulted
but
noticed
revealed
SAITO[5]
and
corrosion
were
have
lack
cracks
surfaces
of
a ƒÁ2
was
seen
showed
phase
on
less
at
in
the
the
corro-
polished
surface[11]. The
surface
amalgam. because of
of
48-h-immersed
High-copper of
its
structural
high-copper
polished
amalgam,
and
mouth
the
6-24
on
carved surface.
AND
the
copper et
amalgam
into
corrosion
surrounding
resistance
high-copper
However,
with
Sn
of
may
MOBERG
started that
Elimination
that
surface
amalgam
the
in
in
type,
polished
specimens
were
corrosion
restoration
high-copper
conventional
pits
similar a
seen
of
that
at
the
had
matrix
and phase
these
vivo
and
be
the
external
been
in
the
vitro
less
studies
the
and in
Cl
the
Cu-Sn
phase
corrosion
in
of
holes
often
in
matrix
high-
appeared.
formed
LIN
extensions
pores. amalgams
significantly[1].
showed
in
surface.
Sn area
and
and
heavy
corrosion
with
that
cracks first,
high-copper
amalgams
the
of
reported later,
showed
corroded
degradadion
that
the
in
on filled
heavily
oxidized
filled
seen
were
ODEN[7]
and to
the
by
specimens
were
pores
of start
pits,
the ƒÁ2 of
cracks
deep
AND
appeared
amalgam
in
smoother
amalgam
and
that Formation
amalgam.
al. [12] found
the
smooth-surface,
within
holes
found
specimens.
high-copper
the
high-copper
Large
MJOR[4]
4-year-immersed below
was
rough
months.
the
JOHANSSON
than
al. [6] reported
boundaries
One-year-immersed porosity
at
et
was
particles
surface
although
grain
specimens
smaller
The
MCTIGUE
of
for
has
integrity.
specimen.
surface
carved
amalgam
In
corrosion
have
than
demonstrated
has our
improved
study,
it
conventional corrosion
the
was
found
amalgam. in
high-copper
amalgam[1,6,7,12]. References [1]
MAHLER,
[2]
LUNDSTROM,
[3]
planus, Mt. J. Oral Surg., PHILLIPS, R. W.: Elements phia,
D.
B.: Research I. M.
C.:
on
Allergy
dental and
amalgam corrosion
13, 16-24, of Dental
1982-1986, of dental
1984 Materials,
3rd
Adv.
Dent.
materials ed.,
185-192,
Res,
in patient W
2, 71-82, with
1988
oral
B Saunders,
lichen
Philadel-
1977
[4]
JOHANSSON, high-copper
B. A. and amalgam,
[5]
JORGENSEN,
K.
D.
and
MJOR, Scand.
I. A.: Marginal J. Dent. Res.,
SAITO, T.:
Structure
and
degradation and 96, 75-82, 1988 corrosion
of dental
corrosion amalgam,
of
a dispersed
Acta
Odontol.
182
Scand., 28, 129-134, 1970 [6] MCTIGUE,D., BRICE,C., NANDA,C. R. and SARKAR, N. K.: The in vitro corrosion of dispersalloy, J. Oral Rehabil., 11, 351-359, 1984 [7] MOBERG, L. E. and ODEN,A.: Microstructure of corroded amalgams, Acta Odontol. Scand., 43, 179-190, 1985 [8] WEIGMAN-HO, L. and KETELAAR, J. A. A.: Corrosion rate studies measurements of corrosion rates of some non-precious dental alloys in artificial saliva, J. Dent., 15, 166-170, 1987 [9] HOLLAND, G. A. and ASGAR,K.: Some effects on the phases of amalgam induced by corrosion, J. Dent. Res., 53, 1245-1254, 1974 [10] YOUNG, F. A. and JOHNSON, L. B.: Strength of the tin mercury phase in dental amalgam, J. Dent. Res., 46, 457, 1967 [11] BOYER,D. B., EDDIE,J. W. and CHAN,K. C.: Effect of surface preparation on phase distribution of amalgam surfaces, J. Dent. Res., 57, 271-276, 1982 [12] LIN, J. H. C., MARSHALL, S. J. and MARSHALL, G. W.: Microstructures of high-copper amalgams after corrosion in various solutions, Dent. Materials, 3, 176-181, 1987
Univ.
Sch.
Dent.,
Vol.
34. 178-182,
Investigation
of
Mahir
words:
Surface
Corrosion
GUNDAY
(Received
Key
1992
and
14 October
high-copper
Nimet
1991
amalgam,
in
and
Amalgam
GENCOGLU
accepted
corrosion,
5 March
1992)
conventional
amalgam,
SEM
Abstract In
this
study,
tional
and
detect
surface
later
surface
high-
investigated
after
by
specimens
and
showed
less
in
holes
than
The
for
in
was at
specimens specimens
saliva
greatest
surface
opening
corrosion
polished
artificial
was
The
deep
and
investigated.
Corrosion
specimens.
visible
carved
was
immersion
SEM.
amalgam
particles
of
amalgams
corrosion
conventional the
corrosion
copper
very
the
48
h
conven-
studied
or
with
and carved
the
contours
High-copper
amalgam
to
1 year,
1-year-immersed
rough
surface.
conventional
of were
of
amalgam
specimens.
Introduction As
well
material
as
with
subject
to
is
a
also
being
unlike
low
tensile
a
corrosion,
of
structure
The
in
of
of
composition
respect
in
the
present
amalgam
of
the
due
with to
Two
types
(ANA The
of
alloys
mm
in
starting after
30
to
placed 37•Ž
in and
a
the
an
Corrosion
of
surface
is
but
the
oral
planus actual
in
amalgam
into
the
of
surface
the
chemical has
deterioration,
species
also
time,
into
lichen
but
metallic
It with
ions
and
fracture, of
was
to
clarify the
mixed
beakers solutions
were
been micro-
surrounding
the
effect
of
nature surface
corrosion
preparation
on
the
used:
Four
(600
(Lumicon)
made manually
in as in
accordance
plugs a plastic
of
each
alloy
were
made,
and
the
others
were
polished
saliva every
after (pH:
polishing,
6.65)[8].
The
the beakers
long
mold
carved,
Immediately
the
with
8 mm
specimens
grit).
and
I).
mercury
were
performed
were
renewed
conventional (Table
with
them
artificial
were
one
content
amalgams was
of
in
Methods
mechanically The
trituration. two
and
high-copper
Condensation
wheel glass
allergy
metals [3].
investigate
alloy
with
condensation,
silicon-carbide
metallic
deposit,
marginal
study
and
amalgam
were
s after
cause
integrity
vitro[1,4-7].
instructions.
diameter.
of
is a brittle
toughness.
surfaces.
2000)
manufacturer's
release
release
amalgam or
structural
surface
Materials
other
to
a
appearance, ductility
its
may
and
and
in
little
degrades
merely
amalgam
vivo
purpose types
only
elements with
corroded
both
two
not
non-metallic
of
milieu
not
and
products is
extensively
structure
concern
Corrosion
studied
of
which
Corrosion
mouth[2].
tooth
strength
biocompatibility
environment[1].
reaction
the
the and
for and
were
s,
24
h
with
specimens
2
60
a
were stored
at
month.
Department of Conservative Dentistry and Endodontics, Faculty of Dentistry, Marmara University, TURKEY To whom all correspondence should be addressed.. Mahir GUNDA Y, c/o Nimet Gencoglu, Anafartalar sok Fulya ap 3/ 1, Yesilkoy, Istanbul, TURKEY.
179
Table
I
Two amalgam specimens (the carved and the polished) were immersed for a period of 48 h and the other two were immersed for 1 year. Corrosion of the surface of the specimens was studied using a SEM (JEOL-100C). Results Conventional Amalgam The surface corrosion of 48-h-immersed carved and polished specimens is presented in Fig. 1-A, B. The surface was rough with the contours of the particles
1A
1B
1C Fig.
1
The carved
surface (C),
of
48-h-immersed
polished
(D)
carved specimens
1D (A), of
polished
conventional
(B)
specimens
amalgam
and (•~500)
1-year-immersed
180
Fig.
2
The carved
surface (C),
of 48-h-immersed polished
(D)
2A
2B
2C
2D
carved specimens
(A), of
polished
high-copper
(B)
specimens
amalgam
and
1-year-immersed
(•~500)
visible on the carved specimen. Although smoother in appearance, small pores were seen on the polished specimen. The surface of a 1-year-immersed carved specimen is shown in Fig. 1-C. Not only a rough surface but also spaces around the particles and deep holes were seen in the carved specimen. On the other hand, pits and small cracks were seen in the polished surface specimen (Fig. 1-D). High-Copper Amalgam The surfaces of 48-h-immersed specimens
are shown
in Fig. 2-A, B. The
polished surface was smoother than the carved surface on the specimens. The surfaces of 1-year-immersed specimens are shown on Fig. 2-C,D. Rough surface of the polished specimen and different sizes of particles were seen in the same sample. Holes and cracks were seen in the carved surface specimen. Discussion The carved surface of conventional amalgam was rougher than the polished surface in 48-h-immersed specimens. Although the polished surface was smooth, pits and pores were also seen on the surface. Besides porosity,
large spaces between
181
the
particles
and
amalgam.
holes
Studies
amalgam
is the
surface
weakest
contains
JORGENSEN
Sn
AND
dominant,
immersed cause
also
small
propagating saline
the
than
and
weeks,
of
and
surfaces
AND
ODEN[7] layer
Cl.
The
region
In
our
study,
surface the
most
not of
most
only 1-year-
common
enlarging
the
pit
and
investigated
amalgam
soaked
products
containing
corrosion
pores
and
polished
the
was
of of
study, of
the
amalgam,
phases.
phase
our
Possibly
of
a
because
on
specimens.
found
specimens.
carved
seen
In
corrosive
the ƒÁ2
the ƒÁ2
pores.
were
The
from of
and
disintegration
and
Sn
cracks
conventional
corrosion[9,10].
corrosion
amalgam
further
to
conventional
of
released
voids
of
(tin-mercury)
are
that
MOBERG
35 of
surface
sion
which
indicated
pores
specimens
phase phase
Sn-containing
process. for
the ƒÁ2
ions,
also
was
concentrations
polished
Zn
conventional
solution
high
susceptible
most
in
pores
1-year-immersed
and
small
polished of
in that
and
resulted
but
noticed
revealed
SAITO[5]
and
corrosion
were
have
lack
cracks
surfaces
of
a ƒÁ2
was
seen
showed
phase
on
less
at
in
the
the
corro-
polished
surface[11]. The
surface
amalgam. because of
of
48-h-immersed
High-copper of
its
structural
high-copper
polished
amalgam,
and
mouth
the
6-24
on
carved surface.
AND
the
copper et
amalgam
into
corrosion
surrounding
resistance
high-copper
However,
with
Sn
of
may
MOBERG
started that
Elimination
that
surface
amalgam
the
in
in
type,
polished
specimens
were
corrosion
restoration
high-copper
conventional
pits
similar a
seen
of
that
at
the
had
matrix
and phase
these
vivo
and
be
the
external
been
in
the
vitro
less
studies
the
and in
Cl
the
Cu-Sn
phase
corrosion
in
of
holes
often
in
matrix
high-
appeared.
formed
LIN
extensions
pores. amalgams
significantly[1].
showed
in
surface.
Sn area
and
and
heavy
corrosion
with
that
cracks first,
high-copper
amalgams
the
of
reported later,
showed
corroded
degradadion
that
the
in
on filled
heavily
oxidized
filled
seen
were
ODEN[7]
and to
the
by
specimens
were
pores
of start
pits,
the ƒÁ2 of
cracks
deep
AND
appeared
amalgam
in
smoother
amalgam
and
that Formation
amalgam.
al. [12] found
the
smooth-surface,
within
holes
found
specimens.
high-copper
the
high-copper
Large
MJOR[4]
4-year-immersed below
was
rough
months.
the
JOHANSSON
than
al. [6] reported
boundaries
One-year-immersed porosity
at
et
was
particles
surface
although
grain
specimens
smaller
The
MCTIGUE
of
for
has
integrity.
specimen.
surface
carved
amalgam
In
corrosion
have
than
demonstrated
has our
improved
study,
it
conventional corrosion
the
was
found
amalgam. in
high-copper
amalgam[1,6,7,12]. References [1]
MAHLER,
[2]
LUNDSTROM,
[3]
planus, Mt. J. Oral Surg., PHILLIPS, R. W.: Elements phia,
D.
B.: Research I. M.
C.:
on
Allergy
dental and
amalgam corrosion
13, 16-24, of Dental
1982-1986, of dental
1984 Materials,
3rd
Adv.
Dent.
materials ed.,
185-192,
Res,
in patient W
2, 71-82, with
1988
oral
B Saunders,
lichen
Philadel-
1977
[4]
JOHANSSON, high-copper
B. A. and amalgam,
[5]
JORGENSEN,
K.
D.
and
MJOR, Scand.
I. A.: Marginal J. Dent. Res.,
SAITO, T.:
Structure
and
degradation and 96, 75-82, 1988 corrosion
of dental
corrosion amalgam,
of
a dispersed
Acta
Odontol.
182
Scand., 28, 129-134, 1970 [6] MCTIGUE,D., BRICE,C., NANDA,C. R. and SARKAR, N. K.: The in vitro corrosion of dispersalloy, J. Oral Rehabil., 11, 351-359, 1984 [7] MOBERG, L. E. and ODEN,A.: Microstructure of corroded amalgams, Acta Odontol. Scand., 43, 179-190, 1985 [8] WEIGMAN-HO, L. and KETELAAR, J. A. A.: Corrosion rate studies measurements of corrosion rates of some non-precious dental alloys in artificial saliva, J. Dent., 15, 166-170, 1987 [9] HOLLAND, G. A. and ASGAR,K.: Some effects on the phases of amalgam induced by corrosion, J. Dent. Res., 53, 1245-1254, 1974 [10] YOUNG, F. A. and JOHNSON, L. B.: Strength of the tin mercury phase in dental amalgam, J. Dent. Res., 46, 457, 1967 [11] BOYER,D. B., EDDIE,J. W. and CHAN,K. C.: Effect of surface preparation on phase distribution of amalgam surfaces, J. Dent. Res., 57, 271-276, 1982 [12] LIN, J. H. C., MARSHALL, S. J. and MARSHALL, G. W.: Microstructures of high-copper amalgams after corrosion in various solutions, Dent. Materials, 3, 176-181, 1987
