JPH0576548A - Rebase method for dental prosthesis - Google Patents

Abstract

PURPOSE:To provide the rebase method for a dental prosthesis for restoring the mastication function or speech function of a patient by rebasing the dental prosthesis incompatibilized with the oral mucosa by using a thermoplastic resin having excellent bioaffinity, thereby well fitting the denture base and the oral mucosa again. CONSTITUTION:A thermoplastic resin sheet having the shape approximated to the surface shape of the dental plate is imposed on an oral gypsum model and the dental plate is brought into pressurized contact therewith after softening by heating. Polymers, such as polysulfone, polyether sulfone and polycarbonate, which have the physical and chemical properties dental physiotechnically preferable as the resin for the dental plate are used as the thermoplastic resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention rebases a denture that has become incompatible with the oral mucosa, re-adapts the denture base and oral mucosa well, and restores the masticatory and pronunciation functions of the patient. Concerning the law.

[0002]

2. Description of the Related Art The compatibility of a denture base with the oral mucosa is not always good due to the deformation of the resin for the floor during the molding or the change of the oral shape of the patient over time. There are many clinical reports of inconveniences such as a decrease in the denture and the denture falling off during opening. Therefore, a method of rebasing the denture to restore the compatibility between the denture base and the oral mucosa to restore the masticatory function or the pronunciation function is adopted.

As a rebasing method, a lining method is clinically common, and an intraoral direct rebasing method and an extraoral indirect rebasing method are carried out. As a material used in the direct rebasing method, a room temperature polymerization resin is the most common, but in this case, the acrylic monomer before polymerization often stimulates the oral mucosa of a patient to cause inflammation. Therefore, in recent years, a photopolymerization rebase material with less irritation of monomers has been developed and used clinically. However, these rebase materials are materials composed of acrylic monomers and polymers in any case, and their polymerization is
Since the polymerization is carried out in the presence of oxygen or water, which is a polymerization inhibitor for acrylic monomers, the acrylic monomers, which are harmful to the living body, remain in the end.

On the other hand, as a material used in the indirect rebasing method, in addition to an acrylic rebase material, a fluoropolymer, a polyolefin thermoplastic resin or the like is used as a soft rebase material. However, the soft rebase material may cause problems such as stability or contamination in the oral cavity. Furthermore, the sulfone-based dentures, which have recently been used more and more clinically, are characterized by excellent biocompatibility, but the shape of the patient's oral cavity changes during use and the denture base and oral mucosa change. If the compatibility with is poor, the rebase is performed using an acrylic direct rebase material, and thus the original excellent biocompatibility is lost.

[0005]

DISCLOSURE OF THE INVENTION The present invention uses a thermoplastic resin having excellent biocompatibility to rebase a denture that has become incompatible with the oral mucosa, and re-adapts the denture base and oral mucosa well. The present invention provides a denture rebasing method for restoring the masticatory function or the pronunciation function of a patient.

According to the denture rebasing method of the present invention, a thin plate made of a thermoplastic resin having a shape similar to the surface shape of a denture base is placed on an oral gypsum model, heated and softened, and then the denture base is pressure-welded. Is characterized by. As the thermoplastic resin used in the present invention, a polymer such as polysulfone, polyether sulfone, or polycarbonate having physical properties and chemical properties preferable for dental denture base resin in terms of dental science and engineering is used.

Further, the present invention is a method in which a denture base is pressed against a softened rebase material to rebase, and a polymer such as polysulfone that flows only when heated to a high temperature is used as a rebase material. It cannot be heated to such a high temperature that it is deformed, and inevitably the rebase material is pressure-welded in a state where the fluidity is not sufficient. Therefore, the shape of the rebase material needs to be a thin plate having a shape similar to the planar shape of the denture base to be lined.

The thickness of the rebase material is preferably 0.5 to 5 mm, more preferably 1 to 3 mm. When the thickness of the rebase material is thicker than 5 mm, the excess resin that should flow out of the molding die during compression molding increases, but as described above, the fluidity of the rebase material is insufficient, so the excess resin is completely removed. Not flow out into the denture, resulting in a high occlusal height of the denture. On the other hand, when the thickness of the rebase material is less than 0.5 mm, air bubbles are generated in the denture base after molding due to lack of resin.

The present invention will be described in detail below with reference to examples. Example 1 A polysulfone denture having a poor fit between a model and a denture base assuming an oral cavity and an average gap between the model and the denture base of 0.7 to 1 mm was prepared, and a fit checker was used according to a conventional dental method. Was used to fill the gap between the model and the denture base. The denture base was removed from the model together with the fit checker, boxed and the molding model material was injected into the mucosal surface of the denture base. While the denture was attached to the molding model material, it was first embedded in the flask, and then a space for accommodating the excess rebase material during compression molding was formed, and then secondary burying was performed. After the investment material hardened, the mold was opened, the fit checker was removed from the denture base, and the mucosal surface of the denture base was further removed. After that, the upper flask in which the dentures were embedded was treated at 130 ° C, and the lower flask holding the molded model was treated at 250 ° C for 1 hour. A 2 mm thick rebase material made of polysulfone was placed on the model, and a far infrared heater was used. After being softened by, it was compression molded using a hydraulic press with a mold clamping force of 2 tons. As a result, the average gap between the denture mucosa of the denture and the model after rebasing was 0.15 m.
m, and the compatibility was good. Further, the adhesive strength between the rebased denture base and the rebase material was 200 kgf / cm ² , and they were firmly bonded.

Example 2 In the same manner as in Example 1, a mold for embedding an acrylic denture was prepared, the mucosal surface of the acrylic denture base was further deleted, and the acrylic denture base and the rebase material were bonded together. After applying the adhesive, compression molding was performed under the same conditions as in Example 2 using a polycarbonate thin plate having a thickness of 3 mm as a rebase material. As a result, the gap between the denture base and the model is 0.18 m
m, and the adhesive strength was 120 kgf / cm ² .

[0010]

According to the denture rebase method of the present invention, since a thin plate made of a thermoplastic resin is used as the rebase material,
There is no problem such as contamination of the oral cavity with acrylic monomers,
The incompatible denture can be stably rebased, and the masticatory function or the pronunciation function of the patient can be restored more reliably.

Claims (1)

[Claims] 1. A method for rebasing a denture, which comprises placing a thin plate made of a thermoplastic resin having a shape similar to the surface shape of a denture base on an oral scout model, heating and softening the denture base, and pressing the denture base.