Background technology
The root canal of suffering from tooth is dental pulp disease and the most effective Therapeutic Method of periapical disease, by the root pipe is cleared up, shaping and filling, can solve infectious root canal tooth preservation problem.Root canal appliance is in root canal, makes it to be shaped or to pull out residual pulp in the root pipe, removes one of important root canal appliance of chip.Because suffering from dental caries that tooth took place, to decrease get involved degree, pulp cavity size, root pipe thickness, length of destructiveness, the tip of a root different with flexibility, make the structure more complicated of root canal system, the root canal preparatory instrument tends to bend with root pipe situation when treatment.
The root canal appliance that uses mostly is rustless steel and TiNi alloy material at present.
(1) stainless steel material its elastic strain amount when stressed is minimum, true plastic deformation usually takes place, and apparatus self deforms when causing treating, and brings resistance thereby give the rotation of root canal appliance and lift, influence enlarges effect, and through rupturing easily after the bending several times.If broken apparatus in the root pipe, is difficult to take out, bring extra misery to the patient.In addition, the cutting blade of rustless steel root canal appliance is not only sharp inadequately, and when carrying out the grinding of root pipe medial wall, wearability is relatively poor, polishes cutting blade easily, reduces stock removal rate, even can't use.
00258208.2), the titanium nickel reamer (patent No.: ZL01260828.9) (2) applicant is successively designed flexible tubular titanium-nickel apparatus without deformation and production technology (application number 00130007.5) thereof, undeformed flexible titanium nickel alloy root canal file (application number:.The result shows, the complication system structure that TiNi alloy root canal appliance can good conformity root pipe, and file finishing and enlarge root pipe medial wall is difficult for deforming and rupturing effectively.Yet, may cause patient's sensitivity response owing to contain nickel element.NiTi alloy elastic modelling quantity is very little simultaneously, strain during its work is very big, often handle end has rotated multi-turn, true twisting could take place in the tip of apparatus, most strains have all been consumed on length, so it is not sharp that doctor's feel becomes, and causes error in judgement easily, and apparatus is twisted off in the tooth.
Obviously, actual clinical more needs the product of a kind of its consistency and elasticity distortion between rustless steel and NiTi alloy root canal appliance, to remedy the deficiency of existing product.
Summary of the invention
The invention provides a kind of novel root canal appliance, its consistency and elasticity is between rustless steel root canal appliance and TiNi alloy root canal appliance, and complication system structure that can good conformity root pipe enlarges root pipe medial wall effectively, is difficult for deforming and rupturing.The cutting blade of root canal appliance is sharp, and pliability, wearability are good.
The present invention also provides the production method of this root canal appliance.
A kind of titanium alloy root canal appliance, comprise naked pin of root canal appliance and handle, the material that it is characterized in that the naked pin of root canal appliance is the TiMoZrSn alloy, the weight percentage of material is: molybdenum 10.0%-13.0%, zirconium 4.5%-7.5%, stannum 3.75%-5.25%, oxygen content is less than 0.18%, phosphorus content is less than 0.10%, and hydrogen content is less than 0.02%, and nitrogen content is less than 0.05%.
The naked pin of described root canal appliance has a working end, the working end outline is a taper, tapering is 0.02~0.20, work tip diameter 0.05mm~1.40mm, the vertical section of its cutting edge is shaped as that circle, square, rectangle, triangle, protruding triangle, triple helical are linear, S shape, three U-shapeds or three W shapes.
Described handle is metal handle or medical macromolecular materials handle.Anti-skidding rib is arranged on the described handle.
The production method of titanium alloy root canal appliance is characterized in that adopting following steps: the acquisition of the smelting of material, blank processing, silk material and pretreatment, cutting blade molding, surface peening and light processing and handle install additional.
The vacuum self-consumption electrode arc melting method is adopted in the smelting of described material, in proportion that highly purified spongy titanium powder, molybdenum bar/powder, zirconium bar/silk and stannum silk/paper tinsel is compressed together, form cylindric electrode, melting voltage is in 20V~50V scope, electric current is in 1000A~3000A scope, vacuum is not less than 10-2Pa, obtains the ingot casting blank.
Described blank processing is that ingot casting is excised rising head, remove surface scale and subcutaneous blowhole, the blank economy-combat grinds off fault in material, 900 ℃~1100 ℃ insulations 1~3 hour, forge into square billet, reroll and make pole, at 800 ℃~900 ℃ pole is swaged, obtain crin, the thermal oxide skin of grinding skin obtains the circle silk then.
The acquisition of described silk material and pretreatment are to utilize circle, triangle or square wire drawing die by the road drawing circle silk, cold-drawn after the first hot drawing, and draw speed is 0.5-1.2m/s.
Described is circle filament diameter/triangle circumscribed circle diameter/when square diagonal is 0.55~3.00mm by the road drawing, pass reduction is 15~22%, circle filament diameter/triangle circumscribed circle diameter/when square diagonal is lower than 0.50mm, pass reduction should be 5~8%, and the working modulus of annealing back first passage is taken off limit; Circle filament diameter/triangle circumscribed circle diameter/when square diagonal is 1.0~3.0mm, the intermediate annealing temperature should be 600~650 ℃, temperature retention time 10~20min, total working modulus between twice annealing is between 60~75%, circle filament diameter/triangle circumscribed circle diameter/when square diagonal is 0.5~1.0mm, the intermediate annealing temperature is 500~550 ℃, temperature retention time 10~20min, total working modulus between twice annealing is between 60~80%, circle filament diameter/triangle circumscribed circle diameter/when square diagonal is 0.2~0.5mm, annealing temperature is 500~550 ℃, temperature retention time 40min, and the total working modulus between twice annealing is 60%.
Described cutting blade molding is pretreated silk material to be drawn into taper rotates the system turned round again or spin finishing becomes taper again by required cutting blade vertical section shape cutting.
Described surface Hardening Treatment is to adopt sandblasting machine, with schmigel and quartz sand cutting blade is strengthened with wearability and is handled, and it is to utilize the cloth wheel to add antiscuffing paste to carry out that described surface-brightening is handled.Described antiscuffing paste is a white fused alumina.
It is that the naked pin of root canal appliance is pressed in the metal handle that described handle installs additional, realizes interference fit or add with the thermoplastic machine loading onto plastic handle.
Titanium alloy root canal appliance of the present invention adopts the medical TiMoZrSn alloy of energy, and intensity exceeds nitinol alloy wire 40%, and rigidity is 40% of stainless steel silk, meets the requirement of root canal appliance material.
The working end of TiMoZrSn alloy root canal appliance is taper (as Fig. 1), the sectional area of its cutting blade can be prepared into different shape,, S shape linear as circle, square, rectangle, triangle, protruding triangle, triple helical, three U-shapeds and three W shapes are (as Fig. 2-Figure 10), to adapt to complicated root canal system.
The titanium alloy root canal appliance, the acquisition of the smelting of process material, blank processing, silk material and pretreatment, cutting blade molding, surface peening and light processing and handle install additional and make.The acquisition of silk material and pretreatment are meant the φ 3mm circle silk process wire drawing die that blank processing is obtained by the road drawing, cold-drawn after the first hot drawing, and draw speed is 0.5-1.2m/s.Obtain the silk material of all size, specification.Cross sectional shape cyclotomy mould, three angle moulds or the rectangular mold of wire drawing die, mold material adopts carbide or carbide alloy, adopts suds or water base molybdenum bisuphide to make lubricant.Silk material diameter/triangle circumscribed circle diameter/when square diagonal is 0.55~3.00mm, the drawing passes working modulus is 15~22%, silk material diameter/triangle circumscribed circle diameter/when square diagonal is lower than 0.50mm, the drawing passes working modulus should be 5~8%, and the working modulus of annealing back first passage is taken off limit; Silk material diameter/triangle circumscribed circle diameter/square diagonal should be 600~650 ℃ in the silk material intermediate annealing temperature of 1.0~3.0mm, temperature retention time 10~20min, total working modulus between twice annealing is between 60~75%, silk material diameter/triangle circumscribed circle diameter/square diagonal should be 500~550 ℃ in the intermediate annealing temperature of 0.5~1.0mm, temperature retention time 10~20min, total working modulus between twice annealing is between 60~80%, silk material diameter/triangle circumscribed circle diameter/square diagonal should be 500~550 ℃ in the intermediate annealing temperature of 0.2~0.5mm, temperature retention time 40min, the total working modulus between twice annealing is 60%.
The silk material of drawing is again by the pattern cutting blade molding of required cross section, as the cross section is that triangle, square or its forming processes of orthogonal root canal appliance change from slightly carrying out the transition to thin uniform gradient for being drawn into area of section at first along its length, adopt then and turn round the system machine and be rotated to turn round and make twisted shape, obtain the geometry of final root canal appliance; The cross section is that circle, protruding triangle, triple helical are linear, its forming processes of root canal appliance of S shape, three U-shapeds and three W shapes is grinding and cutting working method, to carry out surperficial spin finishing through pretreated silk material earlier, grind tapered carefully bar-shaped, then the silk material through the tapering preparation is carried out machining, the cutting blade cross section requirement different according to root canal appliance, the carbide alloy cutting knife that Design and Machining is different carries out machining.
The root canal appliance that makes as stated above promptly can be used for clinical treatment through high temperature, high pressure or chemical disinfection.
Root canal appliance of the present invention is compared with existing NiTi alloy root canal appliance, do not contain the Ni element in the TiMoZrSn alloy, eliminated toxicity and the sensitivity response of Ni to patient, safety is higher, stronger than NiTi alloy root canal appliance simultaneously, can remedy the softer deficiency of NiTi root canal appliance; Compare with existing rustless steel root canal appliance, elastic modelling quantity is less, and rigidity has only stainless about half, can remedy the too hard deficiency of rustless steel root canal appliance, effectively reduces the appearance of various complication in the pain of patient in the therapeutic process and the therapeutic process.
Root canal appliance of the present invention can be with the structure free bend of complicated root canal system, no true deformation is introduced in endodontic procedure, can recover straight fully after the taking-up, residual pulp efficient height in the cutting root pipe, simultaneously its cutting edge part can more effectively have been given play to the gentle repair function of its apparatus when straight under case of bending, be convenient to that the doctor lifts and rotating operation, alleviate cleaning and finishing root needed time of pipe and workload, reduce the chance that causes root pipe complication.This root canal appliance cutting effect is good simultaneously, efficient is high, repeatedly uses and does not rupture, and cutting blade is not easy wearing and tearing, and the surface is not easy to get rusty when disinfecting, long service life.
Root canal appliance of the present invention also has following effect:
(1) intensity exceed nitinol alloy wire 40% and rigidity just stainless steel silk 40%.
(2) the maximum deflection angle all is higher than ISO3630 specified standard angle, and does not show the permanent deformation angle.
(3) moment of flexure is low, the pliability height, and the load that imposes on the tough portion of cutting in crooked root tube greatly reduces, and has reduced the pressure of apparatus.
(4) its cleaning shaping root pipe ability of test on the resin simulation root pipe and the tooth that exsomatizes.The result shows that it does not cause the root pipe choking, and preparation root pipe is quick, non-cracking or distortion, and preparation back root pipe global shape is all better, demonstrates fluency and tapering preferably.
(5) no nickel, non-toxic reaction and zest guarantee that the responsive patient of nickel is safe in utilization.The surface is not easy to get rusty when disinfecting.
The specific embodiment
The present invention is described in further detail below in conjunction with embodiment.
For fear of repeated description, in the production method of embodiment 1-3, the 1st, 2,5,6 procedure of processings are identical, lump together narration, and narration is respectively adopted in the processing of the 3rd, 4 steps.
Proportioning raw materials:
Embodiment 1: pure molybdenum powder 1100g, pure zirconium strand 500g, pure tin strand 400g, titanium sponge 8000g.
Embodiment 2: pure molybdenum powder 1000g, pure zirconium strand 450g, pure tin strand 525g, titanium sponge 8025g.
Embodiment 3: pure molybdenum powder 1300g, pure zirconium strand 750g, pure tin strand 375g, titanium sponge 7575g.
1, the smelting of material
Adopt the vacuum self-consumption electrode arc melting method, the pure molybdenum powder of raw material, pure zirconium strand, pure tin strand and titanium sponge are pressed into consutrode.Melting voltage is in 20V~50V scope, and electric current is in 1000A~3000A scope, and vacuum is not less than 10
-2Pa obtains the ingot casting blank, as shown in figure 11.
2, the processing of blank
Ingot casting is excised rising head, the surperficial defectives such as scale removal, subcutaneous blowhole that strip off the skin through lathe, defectives such as that the blank economy-combat grinds off is folding, pipe, crackle, between 950 ℃, be incubated 2 hours then, forge into 70mm * 70mm square billet, progressively be swaged into 30mm * 30mm square billet again, roll circle subsequently, passage is φ 28mm → φ 26mm → φ 24mm → φ 22mm → φ 20mm → φ 18mm → φ 16mm → φ 14mm → φ 12mm → φ 10mm → φ 8mm.850 ℃ of temperature the pole of φ 8mm is swaged, passage is the crin of φ 8mm → φ 7mm → φ 6mm → φ 5mm → φ 4mm → φ 3.4mm diameter, and grinding skin oxide skin obtains φ 3mm silk material, as shown in figure 12 then.
3, the further processing of silk material
With diameter is that the TiMoZrSn alloy circle silk of 3mm utilizes wire drawing die to pursue to draw and dials, and the wire drawing die pass selects that round mould is arranged, three kinds of triangle mould and Fang Mo.
Embodiment | Heat is dialled | Cold group |
Temperature (℃) | Speed (m/min) | Per pass deflection (%) | The wire drawing die pass | Final sectional area size (mm
2)
| Speed (m/min) | Per pass deflection (%) | Final sectional area size (mm
2)
|
1 | 500 | 7 | 22 | Circular | π×(0.35)
2 | 3 | 5 | π×(0.30)
2 |
2 | 600 | 28 | 19 | Rectangle | 1.0×1.0 | 4 | 7 | 0.8×0.8 |
3 | 750 | 70 | 15 | Triangle | /4(1.0 ×1.0) | 5 | 5 | /4(0.6 ×0.6) |
4, cutting blade forming processes (as Figure 13)
Embodiment 1: adopt the embodiment 1 TiMoZrSn alloy circle silk material surface spin finishing of numerically controlled lathe to above-mentioned processing, make carefully rod of taper, tapering 0.02, and then carry out machining, obtaining the cross section is circular Hedstrom apparatus, work tip diameter 0.15mm.
Embodiment 2: with above-mentioned cross section of handling embodiment 3 is that orthogonal TiMoZrSn alloy silk is drawn into taper along its length, and tapering 0.08 adopts then and turns round the system machine to being rotated, and turns round and makes twisted shape, obtains the Kerr apparatus, work tip diameter 0.60mm.
Embodiment 3: with above-mentioned cross section of handling embodiment 2 is that leg-of-mutton TiMoZrSn alloy silk is drawn into taper along its length, tapering 0.2 adopts then and turns round the system machine to being rotated, and turns round and makes twisted shape, obtain the Reamer apparatus, work tip diameter 0.35mm.
5, cutting blade Strengthening and Toughening and wearability processing, surface-brightening are handled
Adopt sandblasting machine, TiMoZrSn alloy cutting blade is carried out local strengthening with schmigel and quartz sand.The diameter of sand grains is about 0.5mm.The sandblast time is 1 hour.
Devices use cloth after above-mentioned processing wheel is added antiscuffing paste carry out the processing of TiMoZrSn alloy apparatus surface-brightening, antiscuffing paste adopts white fused alumina, and granularity is 0.5 μ m-3 μ m.
6, reinforce handle
Reinforce plastic handle with the thermoplastic machine in the end of the naked pin of TiMoZrSn alloy apparatus, handle is cylindrical, for anti-skidding, anti-skidding rib is arranged on the handle.As Figure 14.This root canal appliance promptly can be used for clinical treatment through high temperature, high pressure or chemical disinfection.Figure 14 is a TiMoZrSn alloy root canal appliance.Root canal appliance of the present invention is made of naked pin 1 of root pipe and handle 2, and the naked pin of root pipe has the working end 3 of a taper.The working end can be made into various cross sectional shapes as required.