CN115887233A - Root canal filling paste and method of use thereof - Google Patents

Abstract

The invention relates to a root canal filling paste and a using method thereof, belonging to the technical field of root canal filling. The root canal filling paste is composed of a type A root canal filling paste containing a pore forming agent and a type B root canal filling paste without a pore forming agent, and the type A root canal filling paste containing a pore forming agent and Type B root canal filling paste without pore-forming agent should not be touched before use; type A root canal filling paste containing pore-forming agent is a self-curing paste; type B root canal filling paste without pore-forming agent is also Self-curing paste. The method of use includes first filling the pulp cavity with type A root canal filling paste, then introducing type B root canal filling paste, and continuing to introduce type B root canal filling paste until the pulp chamber is completely filled with type B root canal filling paste ; Finally fully cured. In the present invention, when the two pastes A and B are placed in the environment of the human body according to an appropriate operation method, a structure in which the porous paste wraps the dense paste can be formed. After the paste cures sequentially, the dense areas can effectively seal the root canal, and the porous areas can facilitate cell ingrowth.

Description

Root canal filling paste and how to use it

technical field

The invention relates to a root canal filling paste and a using method thereof, belonging to the technical field of root canal filling.

Background technique

Inside the root canal of a tooth is the pulp, which contains nerves and blood vessels. When the dental pulp is infected due to deep caries, a fractured crown, or more serious conditions, an abscess and inflammation may form at the apex of the root canal. It causes inflammation to spread in the gums, leading to swelling of the gums in mild cases, and systemic symptoms such as swollen lymph nodes and fever in severe cases. Today, when the pulp of a tooth becomes infected or inflamed, the most common method is to perform root canal surgery. The purpose of healing is achieved by removing the pulp, disinfecting the inside of the root canal, and sealing the pulp cavity with a root canal filling material. An ideal root canal sealing material must meet the following conditions: easy to place; it can be liquid or semi-solid, but it must become solid in the end; it can seal the root canal side branches and apex; the volume will not shrink; it is not sensitive to moisture; Bacteriostatic; does not irritate periapical tissue; does not discolor teeth; easily removed; material is sterile or sterilizable; radiopaque. The quality of the apex seal mainly depends on the performance of the root canal filling material and the operation skills of the root canal filling. The performance of the root canal sealer is the key to sealing the root tip,

Chinese patent CN103690376A discloses that pulp root canal filling paste has the ability of antibacterial, repairing damaged cells in the oral cavity and promoting pulp regeneration. However, it contains zinc oxide and will continue to shrink after curing. According to many studies, the shrinkage rate of zinc oxide paste can reach 0.3%-1% within 4 weeks after filling, which means that the gap between the paste and the root canal wall Gaps will form between them, resulting in micro-leakage. U.S. Patent US20100081113A1 provides a resinous root canal filling paste that has high strength, is not easily broken, has proper deformation, is convenient for root canal filling, and is not easily deteriorated by sterilization or chemical disinfection. But the technique doesn't take into account some of the problems posed by subsequent growth of bone tissue.

As modern medicine has put forward higher requirements for root filling pastes such as promoting bone tissue growth, osseointegration, and inducing periapical tissue regeneration, two-component pastes have received more and more attention. Chinese patent CN201811424104.X proposes a two-component composition for dental root canal filling. The filling effect of high bonding strength and high flexural strength is obtained through the cooperation of the matrix group and the curing group paste. However, the resinous material contained in the matrix set may lead to the risk of bacterial infiltration over time, leading to failure of follow-up therapy. Chinese patent CN107997972A provides a filling paste using independent reagents A and B. This invention can produce calcium phytate and other precipitates by adjusting the pH value to achieve in-situ sealing of the lumen. Both of these two inventions can obtain a good root canal sealing effect, but cannot provide a certain pore structure to promote the growth of bone tissue. Chinese patent CN102113965B provides a porous bone cement that can be used to treat dental and bone defects. But this invention cannot guarantee that the teeth repaired by the porous bone cement will not be infected because of the bacteria infiltrated into the pores. So far, there are still many difficulties in achieving effective sealing and promoting tissue growth and regeneration at the same time. Therefore, it is necessary to develop a filling paste that can not only generate a pore structure to promote bone tissue growth, but also provide a tight filling effect.

Contents of the invention

Aiming at the prior art, the present invention proposes for the first time A-type root canal filling paste containing pore-forming agent and B-type root canal filling paste without pore-forming agent; at the same time, two types of root canal filling A and B are also developed How to use the paste.

The root canal filling paste of the present invention is composed of a type A root canal filling paste containing a pore forming agent and a type B root canal filling paste not containing a pore forming agent, and the type A root canal filling paste containing a pore forming agent and Type B root canal filling pastes without pore builders are left untouched before use.

The root canal filling paste of the present invention, the type A root canal filling paste containing a pore-forming agent is a self-curing paste.

The root canal filling paste of the present invention, the type B root canal filling paste without pore-forming agent is also a self-curing paste.

The root canal filling paste of the present invention, the type A root canal filling paste containing a pore-forming agent includes an inorganic powder system capable of solidifying in a body fluid environment, and includes an X-ray opacifying agent mixture, including a A pore former powder, also contains an organic liquid.

In the root canal filling paste of the present invention, the B-type root canal filling paste includes an inorganic powder system capable of solidifying in a body fluid environment, an X-ray blocking agent mixture, and an organic liquid.

The root canal filling paste of the present invention, the inorganic powder system in the type A root canal filling paste is at least one selected from calcium silicate, calcium phosphate, hydroxyapatite and bentonite. As preferred; the inorganic powder system in the A-type root canal filling paste is composed of hydroxyapatite, tricalcium silicate, tricalcium phosphate, M, bentonite, and calcium phosphate in mass ratio; hydroxyapatite: tricalcium silicate: Tricalcium phosphate: M1: bentonite = 15-25:10-20:40-60:5-15:3-8 composition. Preferably, it is composed by mass of hydroxyapatite: tricalcium silicate: tricalcium phosphate: M: bentonite = 20:15:50:10:5.

Wherein M1 is selected from at least one of calcium carbonate, calcium hydroxide, calcium pyrophosphate, and calcium sulfate.

In the present invention, the pore-forming agent is selected from at least one of sodium chloride, erythritol, polylactic acid, and polyamino acid.

Preferably, the pore-forming agent is composed of sodium chloride, erythritol, polylactic acid, and polyamino acid in a mass ratio of 1.5-2.5:1.5-2.5:0.8-1.2:0.8-1.2.

As a further preference; the pore-forming agent is composed of sodium chloride, erythritol, polylactic acid, and polyamino acid in a mass ratio of 2:2:1:1.

The content of the pore-forming agent in the present invention is 5-25wt.% of the total mass of the powder used in the paste A by mass fraction. Preferably it is 10-15%, more preferably 12-13%.

These components of the pore-forming agent can gradually dissolve during and after the curing of the paste to generate pores, thereby cooperating with the gradual growth of bone tissue. At the same time, the stress caused by the volume expansion of the paste solidification is released by forming pores. Among them, sodium chloride and erythritol, which account for more mass fractions of pore-forming agents, can continue to form pores within one month, and less polylactic acid and polyamino acid can continue to form pores for several months. The purpose of designing the pore-forming agent in this way is to provide sufficient time for osteogenesis while avoiding damage to the dense structure formed by paste B by rapid pore-forming.

The root canal filling paste of the present invention, the preparation method of the A-type root canal filling paste is: the inorganic powder system in the A-type root canal filling paste is mixed with the pore-forming agent powder, and then 25-35% of the total mass of the powder is added. Binder C, stirred evenly to obtain A-type root canal filling paste; the binder C is composed of propylene glycol, polyethylene glycol, and xanthan gum in a mass ratio of 4.8-5.2:4.2-4.7:0.3-0.6.

Preferably, the binder C is composed of propylene glycol, polyethylene glycol, and xanthan gum in a mass ratio of 5:4.5:0.5. In industrial application, mechanical mixing is generally used for mixing.

In the present invention, the amount and composition of the binder C are controlled for the purpose of obtaining a suitable viscosity for subsequent injection and self-curing. The binder is combined with a pore-forming agent, which can create pores at a speed that is more friendly to the body in the human body environment.

The root canal filling paste of the present invention, the inorganic powder system in the type B root canal filling paste is at least one selected from calcium silicate, calcium phosphate, hydroxyapatite and bentonite. As preferred; the inorganic powder system in the B-type root canal filling paste is composed of hydroxyapatite, tricalcium silicate, tricalcium phosphate, M, bentonite, and calcium phosphate in mass ratio; hydroxyapatite: tricalcium silicate: Tricalcium phosphate: M2: bentonite = 15-25:25-35:30-40:5-10:3-8 composition. Preferably, it is composed by mass of hydroxyapatite: tricalcium silicate: tricalcium phosphate: M2: bentonite = 20:30:35:10:5. Wherein M2 is selected from at least one of calcium carbonate, calcium hydroxide, calcium pyrophosphate, and calcium sulfate.

The root canal filling paste of the present invention, the B-type root canal filling paste is prepared by the following method: after taking each powder, add 25-35% of the total powder mass, preferably 30% of the binder D, and stir evenly to obtain Type B root canal filling paste; the adhesive D is composed of propylene glycol and guar gum in a mass ratio of 95-98.5:1.5-5. Preferably, the binder D is composed of propylene glycol and guar gum in a mass ratio of 97.5-98.5:1.5-2.5.

Considering that human teeth contain a large amount of phosphorus and calcium, both paste A and paste B use an inorganic powder system with calcium silicate, calcium phosphate and hydroxyapatite as main components. Considering that different pastes have different functions, the contents of the two ingredients are different, but the types of main ingredients are basically the same.

The method for using the root canal filling paste of the present invention is to first fill the pulp cavity with the A-type root canal filling paste until the apical foramen and part of the root canal are filled with the A-type root canal filling paste; When the agent has solidified for a period of time and is not completely cured, introduce Type B root canal filling paste into Type A root canal filling paste through the equipment, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste agent; then cured.

Because the A-type root canal filling paste and the B-type root canal filling paste in the present invention are all self-curing pastes, after a period of observation, the B-type root canal filling paste can be added to ensure the sealing effect.

As preferably, the using method of the root canal filling paste of the present invention is to fill the type A root canal filling paste in the pulp cavity to the apical hole and part of the root canal filling with the A type root canal filling paste; After filling in place in the root canal, introduce Type B root canal filling paste into Type A root canal filling paste through the device, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste ; and then solidified; the part of the root canal refers to the apical foramen occupying 1/3 and above the height of the entire root canal. In a specific application, as a further preference: after being filled into the B-type root canal filling paste, in the entire root canal, the B-type root canal filling paste does not contact the root canal wall.

As a preference, in the method of using the root canal filling paste of the present invention, after the filling of the type B root canal filling paste is completed; in the height direction, the part where the type B root canal filling paste invades into the type A root canal filling paste accounts for Fill the tube with 1/5~2/3 of the paste. This kind of control is not only beneficial to the subsequent bone formation, but also can avoid the occurrence of non-compactness to the greatest extent.

Preferably, the method for using the root canal filling paste of the present invention is to fill the type A root canal filling paste in the pulp cavity by external force assistance (such as pulling and pressing with a gutta-percha tip). The pulling and pressing of the dental apex can make the A-type root canal filling paste with good fluidity fill the narrow part of the root apex.

Type B root canal filling paste is filled on top of Type A root canal filling paste. When filling, it is necessary to ensure that the type B root canal filling paste filled later is in close contact with the first filled paste A, and the two should be avoided. Mix until the paste fills the pulp cavity to complete the filling. The type A root canal filling paste and the type B root canal filling paste successively solidified after contacting with the moist environment of the physiological body fluid in the pulp cavity. Type A root canal filling paste cures before Type B root canal filling paste. Because the pore-forming agent that dissolves quickly after the type A root canal filling paste is solidified leaves part of the pore channel, which facilitates the diffusion of body fluids to the type B root canal filling paste through the channel, so that the type B root canal filling paste can quickly Solidifies on contact with water. This shortens the time for root canal treatment.

Principles and advantages

The invention provides a pore-forming agent for root canal filling paste and a using method thereof. Considering that human teeth contain a large amount of phosphorus and calcium, the type A root canal filling paste and the type B root canal filling paste all use inorganic powder systems with calcium silicate, calcium phosphate and hydroxyapatite as the main components. .

These components of the pore-forming agent with an appropriate amount of special components in the present invention can be gradually dissolved during and after curing of the paste to generate pores to cooperate with the gradual growth of bone tissue. At the same time, the stress caused by the volume expansion of the paste solidification is released by forming pores. Among them, sodium chloride and erythritol, which account for more mass fractions of pore-forming agents, can continue to form pores within one month, and less polylactic acid and polyamino acid can continue to form pores for several months.

In order to ensure that the pore-forming agent plays a role and form an ideal gradient pore structure, the operation mode provided by the present invention is required to be used in conjunction with it; for example, filling the pulp cavity with type A root canal filling paste to the apical foramen and part of the root canal Apply Type A root canal filling paste; then introduce Type B root canal filling paste into Type A root canal filling paste through the equipment, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste; then solidified; the part of the root canal refers to the position where the apical foramen occupies 1/3 and above the height of the entire root canal. In specific applications, as a further optimization; when filling paste B into paste A, care should be taken not to mix the two pastes. After filling the paste into the B-type root canal, the entire root canal, B-type The root canal filling paste does not come into contact with the root canal wall. Simultaneous control: after the filling of type B root canal filling paste is completed; in the height direction, the part of type B root canal filling paste intruding into type A root canal filling paste accounts for 1/5 to 2/3 of that of type A root canal filling paste 3. This kind of control is not only beneficial to the subsequent bone formation, but also can avoid the occurrence of non-compactness to the greatest extent.

Description of drawings

Fig. 1 is needing to carry out root canal treatment tooth kind;

Fig. 2 is a schematic diagram of the filling effect of the tooth root canal with the gradient pore structure paste.

Detailed ways

The invention will be further described below in conjunction with specific implementation cases. The advantages and characteristics of the present invention will become clearer along with the description, but the implementation cases are only exemplary and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solution of the present invention can be modified and replaced without departing from the spirit and scope of the present invention, but these modifications and replacements all fall within the scope of the present invention. within the scope of protection.

Example 1

Self-curing paste A was prepared. The powder system used in paste A was 20wt% hydroxyapatite, 15wt% tricalcium silicate and 50wt% tricalcium phosphate. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate and calcium sulfate in a total amount of 10 wt%, and bentonite with a mass fraction of 5%. The pore-forming agent is selected from sodium chloride, erythritol, polylactic acid, and polyamino acid, and the mass ratio is 2:2:1:1, and the mass of the pore-forming agent is 5% of the total mass of the paste A powder. After mixing paste A powder and pore-forming agent powder, add propylene glycol, polyethylene glycol, and xanthan gum (5:4.5:0.5) whose total mass fraction is 30% of the total amount of powder, and obtain paste A by mechanical stirring .

Self-curing paste B was prepared, and the powder system used in paste B was 20% hydroxyapatite, 30% tricalcium silicate, and 35% tricalcium phosphate. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate, and calcium sulfate in a total amount not exceeding 10 wt%, bentonite with a mass fraction not exceeding 5%, and the balance being calcium phosphate. Add a total amount of propylene glycol, polyethylene glycol, and xanthan gum mixture (5:4.5:0.5) that are 30% of the total amount of powder by mass fraction, and obtain a paste by mechanical stirring.

How to use root canal filling paste: first fill the pulp cavity with type A root canal filling paste to the apical hole and part of the root canal with type A root canal filling paste; wait until paste A is filled in the root canal After it is in place, introduce Type B root canal filling paste into Type A root canal filling paste through the equipment, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste; then solidify; The above-mentioned part of the root canal refers to the position where the apical foramen occupies about 1/3 of the entire root canal. When filling paste B into paste A, care should be taken not to mix the two pastes. After the filling of type B root canal filling paste is completed; in the height direction, type B root canal filling paste invades type A root canal filling paste The part of the paste accounts for 1/4 to 1/2 of the A-type root canal filling paste (the left and right can be inconsistent, so there will be a range, that is, the right is 1/4, and the left is 1/2). The schematic diagram is shown in Figure 2.

Example 2

Self-curing paste A was prepared. The powder system used in paste A was 20wt% hydroxyapatite, 15wt% tricalcium silicate and 50wt% tricalcium phosphate. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate and calcium sulfate in a total amount of 10 wt%, and bentonite with a mass fraction of 5%. The pore-forming agent is selected from sodium chloride, erythritol, polylactic acid, and polyamino acid, and the mass ratio is 2:2:1:1, and the mass of the pore-forming agent is 12.5% of the total mass of the paste A powder. After mixing paste A powder and pore-forming agent powder, add propylene glycol, polyethylene glycol, and hydroxyethyl cellulose (5:4.5:0.5) whose total mass fraction is 30% of the total amount of powder, and obtain a paste by mechanical stirring Agent A. Self-curing paste B was prepared. The powder system used in paste B was hydroxyapatite with a content of 20%, tricalcium silicate with a content of 30%, and tricalcium phosphate with a content of 35%. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate, and calcium sulfate in a total amount not exceeding 10 wt%, bentonite with a mass fraction not exceeding 5%, and the balance being calcium phosphate. The total amount of propylene glycol, polyethylene glycol, and sodium carboxymethylcellulose cellulose (5:4.5:0.5) was added according to the mass fraction of 30% of the total amount of the powder, and a paste was obtained by mechanical stirring.

How to use root canal filling paste: first fill the pulp cavity with type A root canal filling paste to the apical hole and part of the root canal with type A root canal filling paste; wait until paste A is filled in the root canal After it is in place, introduce Type B root canal filling paste into Type A root canal filling paste through the equipment, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste; then solidify; The above-mentioned part of the root canal refers to the position where the apical foramen occupies about 1/3 of the entire root canal. After the filling of type B root canal filling paste is completed; when filling paste B into paste A, care should be taken not to mix the two pastes. In the height direction, type B root canal filling paste invades type A root canal filling paste The part of the paste accounts for 1/4 to 1/2 of the A-type root canal filling paste (the left and right can be inconsistent, so there will be a range, that is, the right is 1/4, and the left is 1/2). The schematic diagram is shown in Figure 2.

Example 3

Self-curing paste A was prepared. The powder system used in paste A was 20wt% hydroxyapatite, 15wt% tricalcium silicate and 50wt% tricalcium phosphate. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate and calcium sulfate in a total amount of 10 wt%, and bentonite with a mass fraction of 5%. The pore-forming agent is composed of sodium chloride, erythritol, polylactic acid, and polyamino acid in a mass ratio of 2:2:1:1, and the mass of the pore-forming agent is 20% of the total mass of the paste A powder. After mixing the paste A powder and the pore-forming agent powder, add propylene glycol, polyethylene glycol, and carbomer (5:4.5:0.5) whose total mass fraction is 30% of the powder total amount, and obtain paste A by mechanical stirring .

Self-curing paste B was prepared. The powder system used in paste B was hydroxyapatite with a content of 20%, tricalcium silicate with a content of 30%, and tricalcium phosphate with a content of 35%. It also includes calcium carbonate, calcium hydroxide, calcium pyrophosphate, and calcium sulfate in a total amount not exceeding 10 wt%, bentonite with a mass fraction not exceeding 5%, and the balance being calcium phosphate. Add propylene glycol and guar gum (98:2) whose total amount is 30% of the total amount of powder by mass fraction, and obtain a paste by mechanical stirring.

How to use root canal filling paste: first fill the pulp cavity with type A root canal filling paste to the apical hole and part of the root canal with type A root canal filling paste; wait until paste A is filled in the root canal After it is in place, introduce Type B root canal filling paste into Type A root canal filling paste through the equipment, and continue to introduce Type B root canal filling paste until the pulp chamber is completely filled with Type B root canal filling paste; then solidify; The above-mentioned part of the root canal refers to the position where the apical foramen occupies about 1/3 of the entire root canal. When filling paste B into paste A, care should be taken not to mix the two pastes. After the filling of type B root canal filling paste is completed; in the height direction, type B root canal filling paste invades type A root canal filling paste The part of the paste accounts for 1/4 to 1/2 of the A-type root canal filling paste (the left and right can be inconsistent, so there will be a range, that is, the right is 1/4, and the left is 1/2). The schematic diagram is shown in Figure 2.

Comparative example 1

Weigh 5.0g α-tricalcium phosphate, 2.0g tetracalcium phosphate, 1.0g magnesium oxide, 1.5g potassium dihydrogen phosphate, 0.5g iodoform, the particle size is less than 20μm, and mix uniformly to form a solid phase powder. Weigh 2.0 g of sodium dihydrogen phosphate, 0.5 g of sucrose, and 0.5 g of glucose and fully dissolve them in 10 milliliters of 0.5 mol/L citric acid solution to obtain a solidified liquid phase. Pour the solidification liquid into the solid phase powder at a liquid-solid ratio of 0.3ml: 1mg, and mix it evenly in a syringe to obtain a filling material.

The paste was filled into the pulp cavity model by the commonly used filling method at present.

Comparative example 2

Weigh 10g of composite calcium phosphate salt powder containing calcium hydrogen phosphate, tetracalcium phosphate and hydroxyapatite with a particle size of less than 10 μm, 0.5g of tinidazole, and 0.1g of polyethylene glycol-400 to form a mixture, and use 10g of anhydrous Dimethicone oil to temper it into a paste.

The paste was filled into the pulp cavity model by the commonly used filling method at present.

The application effects of the case and comparative cases are shown in Table 1:

Application effect table

It can be seen from the table that compared with the root filling paste with a single component, the composite paste obtained by combining paste A with a pore-forming agent designed in the present invention and paste B can effectively establish a pore structure and achieve biological growth for bone tissue growth. Fixing provides a good base. In addition, paste B without pore-forming agent added to A and B composite pastes can effectively seal the pulp cavity and reduce the risk of bacterial infiltration just like traditional root filling pastes.

The paste A fully mixed with the pore-forming agent in the three examples was made into a cylinder with a diameter of 6 cm (height 12 cm), and the porosity and strength were tested after the paste A was solidified. It can be seen from the measurement results that when the content of pore-forming agent in paste A is 5%, 12.5%, and 20% by mass fraction, the porosity is 4.86%, 11.4%, and 16.8%, respectively. According to the material compression test report, as the proportion of pore-forming agent in the paste increases, more pores are formed, and the compressive strength of the tissue after the paste is solidified is also smaller. The average compressive strength of paste A in Example 1 is 37MPa; the average compressive strength of paste A in Example 2 is 35.68MPa, and the average compressive strength of paste A in Example 1 is 24.72MPa.

The coagulation time of paste A used in embodiment 1-3, the variation of solubility are as follows table 2:

Table: 2: Both the initial and final curing times of Paste A gradually decrease with the increase of pore former. In actual use, shortening the curing time of paste A can make the pore structure be formed earlier and promote the growth of bone tissue, shorten the treatment time and reduce the risk of infection for patients. Root canal filling materials are primarily used as sealants, but the materials dissolve in the oral environment. The solubility standard is 3%, once it exceeds, it will affect the sealing effect of the paste, and the therapeutic effect will be compromised. Therefore, the paste A used in Example 2 can further improve the use effect of the product, that is, the preferred solution of the present invention is the paste A designed in Example 2.

Table 3 pH value change

Table 3 is: the pH value change of the paste A used in Examples 1-3 is as follows. At the same time, studies have shown that the nano-hydroxyapatite root filling paste has a good antibacterial effect at a pH of about 10. The porosity of agent A is the same as in Examples 1-3, all of which show that the pH value is basically stable at 10-11.5 in a fully cured state from 3 hours uncured to 28 days later. Therefore, the paste of the present invention can satisfy conditions such as antibacterial and reducing inflammation after root canal treatment during actual use.

At this time, in combination with Table 2, it can be verified that the design of the paste A used in Example 2 of the present invention is the most scientific.

Claims (10)

1. A root canal filling paste characterized in that: the root canal filling paste is composed of a type A root canal filling paste containing a pore-forming agent and a type B root canal filling paste without the pore-forming agent, and the type A root canal filling paste containing the pore-forming agent and the type B root canal filling paste without the pore-forming agent are not contacted before use;

the A-type root canal filling paste containing the pore-forming agent is self-curing paste; the type B root canal filling paste without the pore former is also a self-curing paste.

2. The root canal filling paste of claim 1, wherein:

the pore-forming agent-containing type-A root canal filling paste comprises an inorganic powder system capable of being solidified in a body fluid environment, an x-ray retardant mixture, a pore-forming agent powder and an organic liquid;

the type B root canal filling paste comprises an inorganic powder system capable of solidifying in a body fluid environment, and contains an x-ray radiation-blocking agent mixture and also contains an organic liquid.

3. The root canal filling paste of claim 1, wherein: the inorganic powder system in the A-type root canal filling paste is at least one selected from calcium silicate, calcium phosphate, hydroxyapatite and bentonite. As a preference; the inorganic powder system in the A-type root canal filling paste is prepared from hydroxyapatite, tricalcium silicate, tricalcium phosphate, M, bentonite and calcium phosphate according to the mass ratio; hydroxyapatite: tricalcium silicate: tricalcium phosphate: m1: bentonite = 15-25; preferably, the ratio by mass of hydroxyapatite: tricalcium silicate: tricalcium phosphate: m: bentonite = 20;

wherein M1 is at least one selected from calcium carbonate, calcium hydroxide, calcium pyrophosphate and calcium sulfate.

The pore-forming agent is selected from at least one of sodium chloride, erythritol, polylactic acid and polyamino acid; the pore-forming agent is contained in an amount of 5 to 25wt.%, preferably 10 to 15 wt.%, more preferably 12 to 13 wt.% based on the total mass of the powder used in the paste A.

4. The root canal filling paste of claim 3, wherein: the pore-forming agent is prepared from sodium chloride, erythritol, polylactic acid and polyamino acid according to the mass ratio of 1.5-2.5:1.5-2.5:0.8-1.2: 0.8-1.2.

5. The root canal filling paste of claim 1, wherein: the preparation method of the A-type root canal filling paste comprises the following steps: mixing an inorganic powder system in the A-type root canal filling paste with pore-forming agent powder, adding a binder C accounting for 25-35% of the total mass of the powder, and uniformly stirring to obtain the A-type root canal filling paste; the binder C is prepared from propylene glycol, polyethylene glycol and xanthan gum according to a mass ratio of 4.8-5.2: 0.3-0.6.

6. The root canal filling paste of claim 1, wherein: the inorganic powder system in the type B root canal filling paste is at least one selected from calcium silicate, calcium phosphate, hydroxyapatite and bentonite. As a preference; the inorganic powder system in the B-type root canal filling paste is prepared from hydroxyapatite, tricalcium silicate, tricalcium phosphate, M, bentonite and calcium phosphate according to the mass ratio; hydroxyapatite: tricalcium silicate: tricalcium phosphate: m2: bentonite = 15-25. Preferably, the ratio by mass of hydroxyapatite: tricalcium silicate: tricalcium phosphate: and M2: bentonite = 20. Wherein M2 is at least one selected from calcium carbonate, calcium hydroxide, calcium pyrophosphate and calcium sulfate.

7. The root canal filling paste of claim 6, wherein: the type B root canal filling paste was prepared by the following method: adding 25-35% of binder D, preferably 30% of binder D, and stirring to obtain type B root canal filling paste; the binder D consists of propylene glycol and guar gum according to a mass ratio of 95-98.5. Preferably, the binder D consists of propylene glycol and guar gum according to the mass ratio of 97.5-98.5.

8. The method of using the root canal filling paste of any one of claims 1 to 7, wherein: filling A-type root canal filling paste into the dental pulp cavity until the apical pore and part of the root canal are filled with the A-type root canal filling paste; introducing a B-type root canal filling paste into the A-type root canal filling paste through equipment when the A-type root canal filling paste is cured for a period of time and is not completely cured, and continuously introducing the B-type root canal filling paste until a pulp chamber is completely filled with the B-type root canal filling paste; and then cured.

9. The method of using the root canal filling paste of claim 8; the method is characterized in that: filling A-type root canal filling paste into the pulp cavity until the apical pore and part of the root canal are filled with the A-type root canal filling paste; after the paste A is filled in the root canal in place, introducing a B-type root canal filling paste into the A-type root canal filling paste through equipment, and continuously introducing the B-type root canal filling paste until the pulp chamber is completely filled with the B-type root canal filling paste; then curing; the partial root canal refers to the position of the apical pore which occupies 1/3 or more of the whole root canal. In particular applications, as further preference; care should be taken not to mix the two pastes when filling paste a with paste B, and after filling the B-type root canal filling paste, the B-type root canal filling paste does not contact the root canal wall throughout the root canal.

10. The method of using the root canal filling paste of claim 8; the method is characterized in that: after the filling of the B-type root canal filling paste is finished; in the height direction, the part of the type B root canal filling paste which enters the type A root canal filling paste accounts for 1/5-2/3 of the type A root canal filling paste.

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