TABLe 4.2
The.Maximum.Wear.Depth.and.the.Roughness.of.the.BNC-PDMAAm.
DN.Gel,.BNC-Gelatin.DN.Gel,.and.the.UHMWPE.after.Pin-On.Flat.
Testing..(Reproduced.with.permission.of.Yasuda.et.al..2005.)
BNC-PDMAAm
BNC-Gelatin
UHMWPE
Maximum.depth.(μm)
7.80.±.8.67
1302.40.±.867.52
3.33.±.5.77
Roughness.(R a ).(μm)
0.09.±.0.03
Not.measurable a
10.0.±.1.0
a. The.roughness.was.not.measurable.because.the.wear.surface.was.extremely.
fluffy.
84
Bacterial Cellulose
before.testing..In.the.observation.on.the.concave.surface.after.testing,.the.
roughness,.R a ,.averaged.0.008.μm.in.the.PAMPS-PDMAAm gel,.0.23.μm.in.
the.PAMPS-PAAm.gel,.and.0.34.μm.in.the.BNC-PDMAAm.gel.(Table 4.2)..
In.the.BNC-gelatin.gel,.the.roughness.was.not.measurable.because.the.wear.
surface.was.extremely.fluffy..On.the.other.hand,.in.the.UHMWPE,.the.R a .
was.14.1.μm.before.testing,.while.this.value.decreased.to.10.8.μm.after.testing..It.meant.that.the.roughness.of.the.surface.decreased.due.to.wear.
The. above. results. demonstrated. that. the. BNC-PDMAAm. DN. gel. could.
bear.one.million.times.of.cyclic.friction,.although.the.maximum.wear.depth.
was.two.to.three.times.that.of.the.UHMWPE..These.gels.are.also.resistant.
to.wear.to.greater.degrees.than.conventionally.reported.hydrogels..This.is.
an.amazing.property.as.a.hydrogel..On.the.other.hand,.this.study.showed.
that. the. BNC-gelatin. DN. gel. was. not. resistant. to. wear. compared. to. the.
BNC–PDMAAm. gel.. The. maximum. wear. depth. of. other. DN. gels. such. as.
PAMPS-PDMAAm.gel.was.similar.to.that.of.UHMWPE.under.one.million.
times.of.cyclic.friction,.which.was.equivalent.to.50.km.of.friction.(50.mm.×.10 6 )..
In.addition,.the.results.showed.that.the.PAMPS-PAAm.DN.gel.could.bear.
the.one.million.times.of.cyclic.friction,.although.the.maximum.wear.depth.
was.two.to.three.times.that.of.UHMWPE..In.terms.of.the.pin-on.flat.testing,.
it.should.be.noted.that.the.PAMPS-PDMAAm.DN.gel.has.a.unique.ability.as.
a.potential.material.for.artificial.cartilage..The.cellulose-PDMAAm.gel.and.
the. BNC-gelatin. gel. include. natural. materials,. cellulose. and. gelatin,. however,.the.wear.property.of.the.BNC-gelatin.gel.was.extremely.inferior.to.the.
other.DN.gels,.although.that.of.the.BNC-PDMAAm.gel.was.comparable.to.
that.of.the.PAMPS-PAAm.gel..This.is.important.information.to.consider.in.
applying.this.material.
These.DN.gel.materials.have.the.potential.to.be.applied.to.various.types.
of. arthroplasty,. including. not. only. the. substitution. of. UHMWPE. in. total.
joint. replacement,. but. also. substitutes. for. part. of. the. articular. cartilage.
and.the.meniscus,.which.are.contacted.with.the.normal.articular.cartilage..
In  particular,. the. latter. application—development. of. artificial. cartilage.
and.. meniscus—is.a.main.goal.of.our.study..We.expect.that.these.DN.gels,.
especially.the.PAMPS-PDMAAm.DN.gel,.may.have.an.effective.lubrication.
. system.against.normal.cartilage.