The thread fiber pole of usefulness is repaired by tooth section
Technical field
The present invention is the Screw Pile that usefulness is repaired by a kind of tooth section, the particularly Screw Pile of fibre reinforced composites machine-shaping.
Background technology
Along with the continuous development of modern root canal technology and the continuous improvement of dental materials, the trouble tooth of a large amount of tooth body serious defects obtains preserving, and stake nuclear recovery technique is to keep the important means of suffering from tooth and recovering its function.Stake nuclear is to be used to improve the dummy of suffering from tooth resistance form and retention form; Form by stake and nuclear two parts; Cement in the root pipe through stake and to obtain maintenance, recover the form of damaged tooth body, create conditions for suffering from the further artificial crown reparation of tooth or carrying out the artificial tooth reparation as abutment through nuclear.
The existing one-hundred-year history that goes up of the nuclear stake recovery technique of dental defect.Used nuclear stake at present is traditional metal core stake, and traditional view is thought select the higher stake nuclear material of elastic modelling quantity, like metal pile nuclear, is removing a small amount of tissue of tooth like this, just can reach requirement of strength under the less situation of diameter.But because the elastic modelling quantity of metal stake is far above the elastic modelling quantity of tissue of tooth, for example the elastic modelling quantity of corona is 18-20GPa; The elastic modelling quantity of tooth root is 9-10GPa; And the elastic modelling quantity of rustless steel nuclear stake is 180-200GPa, and titanium alloy is examined the elastic modelling quantity of stake near 100GPa, the about 200GPa of elastic modelling quantity of pottery nuclear stake; Therefore not the matching of elastic modelling quantity of metal core stake or stake of pottery nuclear and tissue of tooth usually caused the two bonding interface stress concentration; Cause tooth to be easy to jackknifing, cause tooth to pull out, this situation especially is easy to occur in tooth root.Secondly, traditional metal tooth stake can cause tissue and root of the tooth variable color, and the metal stake exists burn into allergy, toxicity, influence is attractive in appearance and shortcoming such as nuclear magnetic resonance diagnosis.
American-European scholar introduces the Oral Repair field with the stake of nonmetallic fiber nuclear up to the nineties in last century; This difficult problem just is able to solve; Composite fiber stake nuclear (being called for short the fiber stake) relies on its unique characteristic generally to be used in American-European countries rapidly; Stake (nuclear) hat is technological just to be further developed, and in Oral Repair more and more widely.The characteristics of fiber nuclear stake are: 1. close with dentin elastic modelling quantity.2. moderate bending strength and hot strength.3. color and tooth are close, and meet the human body aesthetic features.4. do not have metal protection, do not influence nuclear magnetic resonance, NMR etc.5. excellent biological compatibility is arranged and can repeat reparation property.
Since the nineties in last century, carbon fiber stake (Composipost) was carried out in Europe; Each item performance study of fibrous composite stake gradually deeply; Elastic modelling quantity such as fibre glass stake, silica fibre pile more obtain exploitation, the fibre reinforced composites stake of international monopoly such as US6827576 near Dentinal fiber stake in succession; The flexible pile of the oral system of US6371763; Nonmetal tooth stake and the method for preparing of US5964592; Fiber reinforcement tooth stake of US 5816816 and preparation method thereof also has the external related patent U.S. Patent No. such as the fibre reinforced composites that utilize microwave curing of W02004009646.And the composite material pile for repairing tooth of domestic related patent U.S. Patent No. CN1771889 and forming method thereof.
But, adopt the fiber stake to repair for the many trouble teeth of corona tissue disappearance, need to use the resin heap to mould head in the fiber stake, produce the form of nuclear, with the profile of preliminary recovery corona.The stake of fiber tooth is in clinical practice is used; Existing commercial tooth stake is the straight type stake (see figure 2) that has certain taper; At first adopt metal to be drilled on the remaining root of the tooth and hole, the tooth stake is cemented in obtain maintenance in the root pipe, further adopt the light-cured resin heap to form stake nuclear again; The substrate of fiber stake is highly cross-linked epoxy resin; Nuclear resin be a main matrix with the methyl-propyl of photocuring acid (Bis-GMA) then, the difference of the chemical composition of the two, the fiber stake be difficult to and nuclear resin between firm chemical bond [the Journal of Endodontics2006 of formation; 32:44-47].The combination interface that exists between nuclear resin and the fiber stake is influential to the intensity of dummy.It is one of reason that causes the dummy failure that fiber stake and nuclear resin lack adhesion.In addition, the nuclear resin polymerization shrinkage also can produce stress [Dent Mater 2008 to bonding interface; 24:392-398].Therefore; Adopt existing tooth stake and light-cured resin core to be prone to produce following three problems: (1) occurs in the clinical practice because the repairing failure that stake nuclear unsticking causes; And the chemical interface adhesion is less between stake and the nuclear, produces stress concentration when transmitting stress and is prone to cause stake and nuclear layering or unsticking to cause repairing failure.(2) mould the nuclear of system with the complex light cured resin; Use with high-intensity composite tooth stake; Because of mechanical property difference big; The bonded intensity of chemical interface of only piling the shape resin by the resin matrix and the photocuring of fibre reinforced composites is lower, has increased because of external force influence, the possibility that nuclear is damaged.(3) in addition in clinical manipulation is used, also lean on the adhesion strength of fiber stake that light-curing adhesive forms, the chemical interface between the dentin three lower between straight shape fiber stake and the dentin, the possibility of repairing failures such as unsticking also can taking place, be shifted even extract.
Summary of the invention
The present invention proposes the Screw Pile nuclear that usefulness is repaired by a kind of tooth section, is applied to tooth section and repairs.Mainly be to examine whole mechanical strength to improve stake, increase the sealed power of physics, reduce stress concentration, reducing integrated cost and making things convenient for clinical manipulation is main purpose.
Be to realize above-mentioned purpose, the invention provides a kind of tooth section and repair the stake nuclear thread fiber pole of usefulness that it is characterized in that: the stake of described screw thread nuclear is divided into head, interlude, afterbody;
Head forms on cylindrical base substrate, processing the inclined screw groove; Afterbody is tapered part, and is consistent with the tapered partial shape size of dental drill; Interlude is provided with groove near the tapered part of afterbody, is a slick straight section between the inclined screw groove of groove and head.
Described groove is provided with 1-2, and groove length is 0.5-2.0 centimetre; The length 3.0-6.0 of described inclined screw groove centimetre, pitch is 0.2-0.4 centimetre, and screw thread quantity is 3.0-8.0; The length of described straight section is 4.0-6.0 centimetre, the tapered part 5.0-6.0 of afterbody centimetre.
Described fiber adopts the fiber-reinforced resin matrix compound material base substrate, can adopt the base substrate of circle, rectangle or other cross section of the on-the-spot photocuring molding of pultrusion, prepreg compression molding, photocuring prepreg.
Described unidirectional fibre is with carbon fiber, fibre glass, quartz fibre; High strength glass fiber, aramid fiber, the one or more kinds of assorted fibres of ceramic fibre are for strengthening body; Arrange with unidirectional fibre, wherein the volume fraction of fiber is between 45-65%, and the hot strength of base substrate is greater than 600MPa; The modulus of elasticity in static bending is at 8-50GPa, bending strength: 600-1150MPa.
The cross section structure that described unidirectional fibre strengthens the polymer matrix composites base substrate is the unidirectional fibre enhancing along the base substrate length direction for the kernel of section position; Contain the multidirectional fiber of arranging along cross-wise direction and be divided in peripheral cross-section, its effect is to realize that tear on the surface that the oblique rib machine of ridge stake adds man-hour, defectives such as breach appear in the thread groove tip.
Described peripheral cross-section is divided into and contains the multidirectional fiber of arranging along cross-wise direction and be meant that the surperficial felt, the multidirectional fabric that adopt fiber wait and realize.
The elastic modelling quantity of the Screw Pile nuclear after the processing is at 20-45GPa, and flexural strength is at 800-1150MPa, and fiber volume fraction is greater than 60%.
The present invention adopts unidirectional fibre to strengthen the fiber-reinforced resin matrix compound material of the on-the-spot photocuring molding preparation of polymer matrix composites base substrate such as pultrusion, prepreg compression molding, photocuring prepreg; Its fiber volume fraction is between 45-65%; The fiber volume fraction of general pultrusion is more than 60%; The fiber volume fraction of the base substrate of the on-the-spot photocuring molding preparation of prepreg compression molding and photocuring prepreg is about 50%; Can the elastic modelling quantity of fibrous composite and tissue of tooth are complementary through rational moulding process adjusting and recipe design, the fibrous composite that obtains simultaneously has excellent mechanical property.Though the machining in the later stage a spot of destruction fiber of meeting arranging in composite affects the mechanical properties.But Screw Pile nuclear can satisfy the requirement of tooth dental repair material mechanical property fully, and compares with simple resin core material, and its intensity and the high 5-10 of modulus meeting have doubly solved the problem of clinical repair center material mechanical performance difference.
Repair the actual requirement in using according to tooth section, the Screw Pile nuclear that designs through accurate Calculation has unique appearance structure.Its nuclear stake is the cohesive force during clinical use for inclined screw groove, the tapered structure of middle part dual-cavity and stake portion can satisfy.The tapered part of its afterbody is consistent with the tapered part of dental drill, guarantees the location of stake nuclear in the root pipe; Intermediary two groove parts have then effectively increased bond area, have increased bonding force, have prevented that stake nuclear from insecurely deviating from the root pipe because of bonding; Part between dual-cavity and the nuclear portion inclined screw groove is a slick straight section; The effect that stake nuclear is set upright has been played in its existence in the root pipe; Be convenient to clinical practice; Effectively guaranteed around the stake nuclear and the adhering resin layer thickness between the root pipe evenly suitable, guarantee that enough bonding forces prevent that stake nuclear from deviating from the root pipe.
The helicla flute of head have with stake on the same increase bond area of groove part, increase the effect of bonding force, prevent to examine the phenomenon that causes corona to come off with the bonding insecure of corona.Its unique helical structure has guaranteed that also corona receives force intensity on the circumferential direction of stake nuclear in addition, has effectively prevented in practical application the rotation that corona is produced when the bearing bad external force phenomenon that gets loose.
Description of drawings:
Fig. 1 thread fiber pole of the present invention.
Fig. 2 is the commercial fiber stake shape of relevant in the world manufacturer production.
Fig. 3 is the thread fiber pole size marking figure of embodiment.
The specific embodiment
Embodiment 1:
The pultrusion sample preparation of fiber-reinforced resin matrix compound material base substrate: the basic recipe of matrix resin is: LG-DOW Der331 epoxy resin: 100 parts; Firming agent: methyl tetrahydro phthalic anhydride (80 parts), promoter: DMP-30 (1 part), releasing agent: 1.5 parts; Fortifying fibre is: the HS4 of research of Nanjing fibre glass and designing institute; Tensile strength of fiber is 4600MPa, and elastic modelling quantity is 86.4GPa, and density is 2.53g/cm
3, the extension at break amount is 5.3%.
At diameter is to adopt pultrusion molding process to prepare base substrate in the circular die of 4mm, and its pultrude process adopts three sections mode of heatings, first section temperature: 140 degree, second section temperature: 165 degree, the 3rd section temperature: 185 degree.The batten that pultrusion goes out is after fixing 2 hours in 200 degree baking ovens, obtains the fibre reinforced composites base substrate of embodiment.Wherein the volume fraction of fiber is 62%, the hot strength 800MPa of base substrate, and the modulus of elasticity in static bending is at 45GPa, bending strength: 1100MPa.
Fig. 2 is the commercial fiber stake shape of relevant in the world manufacturer production, and its length is 10-25mm.
The preparation of Screw Pile:
Adopt the miniature numerical control lathe to carry out machining according to Fig. 3 section drawing.The size of its 4 kinds of specifications is seen table one.The elastic modelling quantity of the Screw Pile nuclear after the processing is at 35GPa, and flexural strength is at 1050MPa.
Thread fiber pole of the present invention, its groove are provided with 1-2, and groove length is 0.5-2.0 centimetre; The length 3.0-6.0 of described inclined screw groove centimetre, pitch is 0.2-0.4 centimetre, and screw thread quantity is 3.0-8.0; The length of described straight section is 4.0-6.0 centimetre, the tapered part 5.0-6.0 of afterbody centimetre.
Processing model, specification and the size of table one Screw Pile
Model |
d |
D |
L |
I
1 |
I
2 |
I
3 |
I |
1.8 |
2.2 |
17 |
5 |
6 |
4 |
II |
1.6 |
2.0 |
17 |
5 |
6 |
4 |
III |
1.4 |
1.8 |
15 |
6 |
5 |
6 |
IV |
1.2 |
1.6 |
15 |
3 |
5 |
6 |
Embodiment 2:
The basic recipe system is: light-cured resin monomer bisphenol-A GMA (Bis-GMA); Diluent triethylene Glycol double methyl methacrylate (TEGDMA); Catalyst camphorone (CQ) and aided initiating N; N-dimethylaminoethyl methacrylate (DMAEMA) is all available from Aldrich company.High-strength glass fibre, HS4, tensile strength of fiber are 4600MPa, and elastic modelling quantity is 86.4GPa, and density is 2.53g/cm3, and the extension at break amount is 5.3%, Nanjing fibre glass academy produces.
The on-the-spot photocuring molding blank of photocuring prepreg: take by weighing 49.5gBis-GMA and TEGDMA respectively and be put in the there-necked flask of 250ml; High-speed stirred 6h mix homogeneously; In resin system, add CQ and each 0.5g of DMAEMA then, restir 1h obtains the light-cured resin system.Be put in light-cured resin in the long steeping vat of 30cm, successive fibre glass is passed through steeping vat with the speed of 0.5m/min, strike off unnecessary resin through the glass horn mouth that a diameter is 1.5mm again, collect and obtain the light-cured resin prepreg.In order to prevent the curing in advance of resin, above all operations all is to carry out being equipped with under the faint yellow protection light source (PHILIPS TL-D YELLOW, Holland).
It is long that above-mentioned light-cured resin prepreg is cut into 3cm, and the bottom that is tiled in the hollow of a 3mm * 4mm * 30mm is placed with in the mould of politef of thin glass sheet.Fill up mould with light-cured resin then, upper cover one thin glass is removed unnecessary resin and bubble.According to the ISO10477 standard, with tooth section light-solidified lamp (Densply QHL75, the U.S.), respectively shine 30 seconds up and down after, take out sample and place 24h for 37 ℃.The composite body of preparation is tested on Inostron-1121 type universal material experimental machine, and the pressure head diameter is 2.5mm, span 20mm, loading velocity 1.0mm/min.By formula bending strength δ is calculated in (2) and (3)
f(MPa) and bending modulus E
f(GPa):
δ
f=8F
maxl/πd
3 (2)
E
f=S4l
3/(3πd
4) (3)
Wherein, F
MaxBe bending load; L is the test span; D is a sample diameter; S=F/D, the rigidity of S representative sample, corresponding deformation when wherein D representes that load is F.
The fiber volume fraction of its composite is 48%, and bending strength reaches 546.3MPa; And bending modulus reaches 9.1GPa.
The light curing compound material base substrate of above-mentioned acquisition is carried out machining according to Fig. 3 of embodiment 1, can obtain the Screw Pile sample of four kinds of specifications of table one.The elastic modelling quantity of the Screw Pile nuclear after the processing is at 32GPa, and flexural strength is at 950MPa.