A kind of filler that is used for root canal
The present invention relates to a kind of root canal alloy filling material that is used for.
Current, the filler of filling root canal is commercially available gutta percha point or acupuncture needle through what use always.Gutta percha point is to be added materials such as zinc oxide, calcium oxide, white beeswax to make by Malaysia red ferrum section resin.
Chinese patent literature CN1040920A (application number 89105193.7) has introduced a kind of dental Magnetic-resin filling material.It is to make the water solublity base fluid by formaldehyde and cresols or resorcinol and sodium hydroxide, in the mixed liquor of above-mentioned any base fluid or two kinds of base fluids, adds the ferromagnetism Fe that is enclosed with activator
3O
4Minuteness particle is made root canal filling liquid.This root canal filling liquid has ferromagnetism, flowability and polymerization.
Another piece Chinese patent literature CN1062835A (application number 91107542.9) has introduced a kind of high magnetical solid filling material for periodontal duct.This is to be main body by pure Malaya natural gum and high magnetic material SmCo magnetic powder, is equipped with composite oxide powder and zinc, lithopone and paraffin, through mix homogeneously repeatedly in mixing roll, is processed into circular cone needle-like glue point.Drying technology such as magnetize is made into normalized magnetic gutta percha point again.
The dental Magnetic-resin filling material that Chinese patent literature CN1040920A introduced owing to be a kind of liquid, in use is difficult for being injected into desired area, operation inconvenience.And all contain white beeswax in the high magnetical solid filling material for periodontal duct that above-mentioned commercially available gutta percha point and Chinese patent literature CN1062835A introduce, pinch and in hands, do not have rigidity, feel like jelly, be difficult to insert in the root canal, the operation of therefore being a patient needs long time.Though the commercially available gutta percha point of its strength ratio of acupuncture needle and with the magnetic gutta percha point height that high magnetical solid filling material for periodontal duct is made is easy to insert in the root canal, it is low that the intensity of argent still shows, and inserts in tiny curved canals or extract still very hard.In addition, silver is poor with human compatibility, and acupuncture needle is run into the easy inflammation of tooth palate.
Purpose of the present invention just is to develop a kind of new filler that is used for root canal, and this filler has overcome above-mentioned commercially available gutta percha point, the shortcoming that exists in the prior arts such as root canal filling liquid, magnetic gutta percha point, acupuncture needle.
A kind of filler that is used for root canal of the present invention, be to constitute by the nickel of 54.5~56.7% percetages by weight, the Nitinol that surplus is titanium, it is shaped as wherein a kind of of circular cone spicule, cylinder, the big first end of the tooth root canal filling material of circular cone spicule is little round, the diameter of major part is 0.10-1.0 millimeters, and length is 10-40 millimeters; Any end of cylinder tooth root canal filling material is little round, and diameter is 0.10-1.0 millimeters, and length is 10-40 millimeters.
In order to make this filler be easier to from root canal, extract, be little round at the big first end of the tooth root canal filling material of circular cone spicule.Equally, any end of cylinder tooth root canal filling material also is little round.Circular cone spicule tooth root canal filling material, the diameter of major part is 0.10-1.0 millimeters, again with 0.15-1.0 millimeters for better.Length is 10-40 millimeters.The diameter of cylinder tooth root canal filling material is 0.10-1.0 millimeters, again with 0.15-1.0 millimeters for better, length is 10-40 millimeters.The used Nitinol of the present invention also contains inevitably other impurity elements.
The vacuum melting method of all knowing with the those of ordinary skill under this area is made the nickel-titanium alloy material of required composition, draw wire, be raw material with the qualified thick titanium-nickel wire of composition again, draw with the drawing by high temperature method, generally stretch, break the tooth root canal filling material that just forms the circular cone spicule 400-700 ℃ temperature.Do not move required diameter to and just form the cylindrical shape tooth root canal filling material if do not break.
The advantage of the tooth root canal filling material of being made by Nitinol of the present invention just is that it has excellent corrosion resistance.It in the physiology simulative corrosion test, its corrosion rate<6.8 * 10
-5In millimeter/year, belong to 1 grade of corrosion resistance.And it has the good compatibility again.Its another advantage is to have good super-elasticity, and its yield strength is significantly less than tensile strength sigma
b=(2~4) σ
0.2, it loads the back martensitic phase transformation takes place, easily surrender.Restore to the original state again after the unloading, so it had both had super-elasticity, not brittle failure again so be easy to insert from root canal, is easy to again extract from root canal, and it is a kind of good root canal filling thing.
The stress strain curve figure of the Nitinol tooth root canal filling material that Fig. 1 φ is 0.46 millimeter
Among the figure, abscissa is a deformation rate, %; Vertical coordinate is a volume unit: newton/square millimeter.
0.46 millimeter Nitinol tooth root canal filling material among Fig. 1 is by the nickel of 55.6% percetage by weight, and surplus is that the Nitinol of titanium constitutes, and it is shaped as the circular cone spicule.0.46 millimeter of diameter at butt end φ, long 30 millimeters, tensile strength sigma
b1580MPa, yield strength α
m470MPa, percentage elongation 16%.Stretch in 650 ℃ with said method, break and make.The shape of tooth root canal filling material is seen Fig. 2.
Fig. 2 circular cone spicule tooth root canal filling material sketch map.
Fig. 3 cylinder tooth root canal filling material sketch map.
Be used for the nickel of tooth root canal filling material by 55.0% percetage by weight among Fig. 3, surplus is that the Nitinol of titanium constitutes, and its diameter phi is 0.5 millimeter, tensile strength sigma
bBe 1340MPa.
Fig. 4 circular cone needle-like tooth root canal filling material stub end is ringlet shape sketch map.
Fig. 5 cylinder tooth root canal filling material is ringlet shape sketch map.
With following indefiniteness embodiment tooth root canal filling material of the present invention is further described, will helps the understanding to the present invention and advantage thereof, and not as a limitation of the invention, protection scope of the present invention is decided by claims.
Embodiment 1
Present embodiment be used for the nickel of tooth root canal filling material by 55.2% percetage by weight, surplus is that the Nitinol of titanium constitutes.It is shaped as the circular cone spicule, and diameter at butt end φ is 0.5 millimeter, and tensile strength is σ
b1360MPa, big first end is little round, and length is 30 millimeters, sees Fig. 4.
Embodiment 2
Present embodiment be used for the nickel of tooth root canal filling material by 55.3% percetage by weight, surplus is that the Nitinol of titanium constitutes.It is shaped as cylinder, and its diameter phi is 0.5 millimeter, tensile strength sigma
bBe 1400MPa, the one end long 30 millimeters, is seen Fig. 5 for being little round.