JPS6224404B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to dental image compositions. Dental impression formulations suitable for soft moving tissues must meet the following requirements: (1) have excellent plastic flow at mouth temperature of a minimum of 85% at 37°C; (2) solidify rapidly when exposed to temperatures somewhat below mouth temperature; (3) mouth tissue. or not bonded to the gypsum casting material, but must coalesce into a solid mass but be bonded to the stucco material; (4) the dimensions of the oral tissues without displacing any detail from its true position; reproducing an excellent negative mold with surface details; (5) with excellent dimensional stability at temperatures below the mouth temperature; (6) not be unpleasant or toxic to the patient; (7) have a good shelf life; (8) be easy and convenient to use; and (9) be connected. be sterilizable when in a container. Among the commercially available impression formulations known to the Applicant, EX-3-N- are apparently made in accordance with the disclosure of German Patent No. 1067175.
Gold has the most desirable plastic flow at mouth temperature. However, the impression formulation made according to DE 1067175 cannot be sterilized in an autoclave without affecting its properties. The dental impression composition disclosed herein achieves the above objectives. This imaging formulation has an 85% flow rate, as hereinafter defined, at the temperature of the mouth and a substantially lower flow rate at room temperature, so that it solidifies rapidly upon removal from the mouth. The impression formulation provides excellent reproduction of detail and is easy to handle. The materials used in this composition, namely hydrogenated utudolozin, white petrolatum and the fillers consisting of talc and aluminum powder, provide a heat and light stable composition which does not change its properties before use. Can be sterilized with Other objects, features and advantages of the invention will become apparent from the following disclosure. To evaluate the flow properties of dental impression formulations,
An apparatus was designed and constructed to cast the impression formulation into cylinders 10 mm in diameter and 6 mm in height and to expose each cylinder to 2000 g of pressure for 10 minutes at a selected temperature. The height of the cylinder was measured before and after exposure to pressure. The reduction rate (%) of the height of the cylinder is expressed as the plastic flow of the material at the selected temperature. Figures 1 and 2 show flow percentage versus temperature for various ratios of the components of the composition of the invention. A variety of thermoplastics were tested and hydrogenated uddrosine appeared to have the most advantageous and desirable properties for dental impression formulations. A particular hydrogenated uddrodine that has been tested and found to be effective was manufactured by Hercules, Inc.
STAYBELITE, marketed under the trade mark STAYBELITE by A. Incorporated, is highly resistant to oxidation and discoloration, and to changes in stability properties upon exposure to air and sun. It is gender.
"STAYBELITE" has low taste and odor, and has excellent thermal stability. Various plasticizers were tested and white petrolatum gave excellent results. Petrolatum has reasonable homogeneity, low odor or taste, excellent heat and light stability in accordance with US Pharmacopoeial standards, and most importantly excellent compatibility with hydrogenated utudolozin, so that the mixture When cooled and solidified, the petrolatum has no tendency to migrate or bleed to the surface of the mixture. Mineral oil was tested as a plasticizer in early experiments and showed that it migrated to the surface of the cooling mixture when used with STAYBELITE.
It had a tendency to become sticky. In addition to the thermoplastic hydrogenated utudolozin and the plasticizer petrolatum, to maintain the mixture of the thermoplastic hydrogenated utudolozin and the plasticizer in a rigid solid state when it solidifies, and a rigid solid and a low viscosity liquid A filler is required to increase the operating temperature range of plastic flow between. Fillers are also desirable to reduce the surface tackiness of the mixture. Talc and aluminum powder were found suitable as fillers. Commercial grade Alcan MD3100 and US
Bronge 560 gave excellent results. Both of these aluminum powders are non-flaky, fine, generally spherical powders coated with stearic acid.
AlcanMD3100 has a minimum passing value of 97.0 for 325 meshes.
It is standardized as %. Aluminum powder improves thermal conductivity, so when the composition is brushed onto a platen and preheated, the impression material quickly and uniformly softens to a plastic state, thereby avoiding localized overheating. No subsequent decomposition of the material will occur.
Thus, once the formulation on the balm is placed inside the mouth, all of the mass will be in plastic flow.
Furthermore, when cooling the completed impression with cold water,
All of the materials quickly solidify into a solid state and are not subject to further stress or deformation. When casting a dental stone in an impression, the heat generated during the thermal phase of the solidifying stone is carried away from the composition and the surface of the stone, thus reducing the local melting of the formulation. and the negative effects of interpenetration of plastic and stone, subsequent adhesion and surface damage will be minimal. As long as aluminum has a lower density, the greater volume per unit weight in the composition means that a given weight percentage of aluminum will have a greater effect on the thermal conductivity of the mixture than a similar amount of other heavy metals. It means deaf. Aluminum also has less tendency to settle out of the mixture, as occurs with heavier metals when the mixture is heated to a fluidized state. In early trials, aluminum particles in the form of flakes were used in the preparation of dental impression formulations;
Because formulations containing aluminum flakes did not flow well under stress at mouth temperatures,
Ultimately, they chose particles that were spherical or more regularly shaped. This drawback appears to occur because the irregular shape of the flakes impedes the relative movement of the aluminum particles and because the aluminum particles become entangled with each other. Additionally, large particles of aluminum interfere with obtaining images with the necessary fine detail and sharpness. The USP talc used in the composition is a naturally occurring hydrated magnesium silicate that is reasonably uniform in properties according to USP specifications. of its specific gravity
Since 2.7-2.8 approximates the specific gravity of aluminum, 2.708, they do not tend to separate in the mixture when in the fluid state. Tables 1 and 2 below show various ratios of
Temperature flow characteristics obtained in flow measurements for STAYBELITE, petrolatum, aluminum and talc and their specific compositions are disclosed. Table 1 contains the data for FIG. 1 and shows the percentage flow at various temperatures for compositions 115, 116, 117, 118, and 119. FIG. 1 also includes curve I which shows the desired flow characteristics for this type of tooth impression formulation. This curve I corresponds to the recommended maximum allowable flow, i.e. 10% at 10°C, 15% at 15°C.
20% at 20°C, 55% at 20°C and 85% at the recommended minimum flow, i.e. 37°C or mouth temperature.

【table】

【table】

Table 2 In the experiments recorded in Table 2, changing from one variety of white USP petrolatum to another greatly affected the amount of petrolatum required for desired flow properties. Table 2, Batch 1 contains one type of petrolatum (white, USP) and Batch 2 contains a different type of petrolatum, but in the same proportions as Batch 1. Different flow percentage characteristics were obtained for batches 1 and 2. FIG. 2 also shows the curves of % flow versus temperature for batch formulations 1, 3C, 4 and 5A shown in Table 2 of the present invention. FIG. 2 and Table 2 show that even if the composition of petrolatum is the same, the flow curves will differ if different types of petrolatum are used. Table 3 below shows the composition ranges for dental impression formulations based on formulations 115-119 in Table 1 and batch 1 of Table 2.

Table: Since the properties of an imaging formulation depend on the selection of the mutually independent weight percentages of its constituents, some of the factors influencing the selection will be discussed. Experiments have shown that the total filler content can vary from about 5% to 25%, while maintaining a reasonable plastic flow temperature range around mouth temperature by adjusting and selecting the plasticizer content. can. At filler contents below about 5%, the plastic flow temperature range is narrower than desired, the surface of the warmed mixture increases in tackiness, and even when all the filler is aluminum powder, the thermal conductivity of the mixture decreases. The properties will not be much better than that of the thermoplastic alone. Approximately 25%
For filler contents above, the plastic flow temperature range is
A wider than desired range results in an impression that approaches room temperature and thus loses detail and precision before and during casting of the dental stone positive. For convenience, the total filler content of the formulation is initially chosen to be at or near 15%. At least 5% of this should be aluminum powder so that a significant thermal conductivity improvement is achieved. Additional thermal conductivity improvements are realized by increasing the aluminum powder content to the limit of the total filler content. However, the presence of talc as the balance of the total filler content has the benefit of lowering the cost of the mixture and facilitating the selection of other colors of the mixture. If a pigment is used to produce other colors in the mixture, its weight percentage is subtracted from that of talc, keeping the total filler content constant. Then,
The plasticizer content is chosen to provide sufficient flow at mouth temperature. Even the constituents of this formulation, chosen partly for reasons of uniformity, vary somewhat in their properties from batch to batch, so the exact amount of plasticizer depends on the flow of the experimental composition of the formulation. Must be selected for the total filler content selected on the basis of testing. In practice, the exact amount of plasticizer for a filler content of 15% is about 8% for one petrolatum and about 8% for the other petrolatum.
It was 6.5%. After selecting the filler and finding the exact plasticizer content by experiment, the content of thermoplastic (hydrogenated uddrosine) is of course fixed as it is the remainder of the formulation. To ensure that each batch of impression formulation has the correct flow characteristics, the flow is run at two minimum temperatures, one at 10-15°C and the other at approximately 37°C, using appropriate equipment and methods. Appropriate quality control such as measurement will be necessary. This quality control is especially important whenever new amounts of ingredients are used. Proper palpation technique is required to obtain excellent results with almost any dental material. This fact is also true in the case of this dental impression material. Proper technique is required to obtain good impressions of soft oral tissues using this material.

[Brief explanation of the drawing]

FIG. 1 is a family of curves showing percent flow versus temperature for the five compositions tested. FIG. 2 is a family of curves similar to FIG. 1 showing flow percentage versus temperature for other proportions of chemicals.

Claims (1)

[Scope of Claims] 1 Consisting essentially of a mixture of 65.5-91.0% by weight of hydrogenated uddrozine, 4.0-9.5% by weight of white petrolatum, 0-20% by weight of talc and 5-25% by weight of aluminum powder, consisting of talc and aluminum powder. A dental image composition characterized in that the total amount is 5 to 25% by weight. 2 Consisting essentially of a mixture of 71.5-89.0% by weight of hydrogenated eudrodine, 6.0-8.5% by weight of white petrolatum, 0-15% by weight of talc and 5-20% by weight of aluminum powder, the total amount of talc and aluminum being 5-20% by weight. % by weight of the dental image composition according to claim 1. 3 Hydrogenated uddrozine 76.75-88.75% by weight, white petrolatum 6.25-8.25% by weight, talc 0-10
% and aluminum powder, the total amount of talc and aluminum being 5 to 15% by weight. Image composition. 4. The composition has a maximum allowable flow of 10% at 10°C, 20% at 15°C and 55% at 20°C.
The first claim consists essentially of a mixture of hydrogenated uddrosin, white petrolatum, aluminum powder and talc in proportions such that it has a minimum flow of 85% at 37°C.
The dental image composition according to any one of Items 1, 2, and 3.