Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Processes of preparing a desired or intentional composition...
Patent
1985-06-26
1988-11-08
Clingman, A. Lionel
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Processes of preparing a desired or intentional composition...
4332011, 4332281, 4331991, 522 77, 523116, A61K 608, A61C 800
Patent
active
047834919
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE TECHNIQUE
This invention relates to a dental material having radiation contrastability and, in detail, it relates to a dental material having X-ray contrastability which comprises combining a methacrylate having an aromatic residue substituted by bromine atom in the molecule as polymerizable monomer.
BACKGROUND TECHNIQUES
As the materials for restoration in the field of dental cure such as restoration of a partially lost tooth and the like, plastic materials have been widely used in recent years. The plastic materials are excellnet in strength, aesthetic appearance, modability and economical efficiency and possesses almost properties required as the dental materials for restorative treatment. The plastic material, however, has X-ray permeability in itself and this property has been considered a disadvantage in practical use. Because, when inspections of dental caries, disorder of tissue and the like are required after dental cure, the observation by X-ray contrast is often conducted as a method to inspect the affected part undestructively, but, in this case, the detection of the affected part newly formed becomes difficult if the part to be cured is permeable. Therefore, as another property to be possessed by the dental materials for restorative treatment, X-ray impermeability has been considered important.
As methods to change the X-ray permeable materials to X-ray impermeable ones, the combination of powdery metals or the combination of oxides or salts of X-ray impermeable heavy metals, organic iodie compounds and the like are generally employed. These methods, however, have problems such as check of workability and modability of the plastic materials and deterioration of their water resisting property, transparency, light permeability, strength and the like, and also the fillers of the metals and the like mentioned above can not be combined in certain circumstances, and therefore, these methods could not give X-ray contrastability in fact for this purpose.
DISCLOSURE OF THE INVENTION
This invention is accomplished on the basis of these circumstances and aimes at providing a dental material having X-ray contrastability in which the above-mentioned disadvantages are improved by causing a bromine whch is a X-ray impermeable element to be present in a methacrylate by means of chemical bonding to endow the methacrylate itself which is a polymerizable monomer with X-ray contrastability.
Namely, this invention is characterized by employing a methacrylate which has one or more carbon-bromine bonds in the molecule as polymerizable monomer and, in more detail, it provides a dental material having X-ray contrastability which comprises combining a filler and/or hardener, as occasion demands, with a methacrylate which has a hydrocarbon residue having an aromatic residue substituted by bromine atom as component of the alcoholic side.
However, the too small content of bromine in the above-mentioned methacrylate can not afford a necessary and sufficient X-ray contrastability and, on the other hand, the too much gives a bad effect on the strength, aesthetic appearance or modability of the polymer, though it improves X-ray contrastability. Therefore, the preferable content of bromine atom occupied in the whole molecules of the methacrylate was examined and found to be in the range from 20 to 60 weight %. In this invention, the above methacrylate can also be used independently, but, preferably, it is advantageously used as a polymerizable composition by mixing with a reaction accelerator (e.g., amines) and a hardener (e.g., benzoyl peroxide, etc.) in order to control the reaction rate of the said polymerizable monomer or the hardness of the molding suitably and, moreover, various fillers (silica, quartz powder, metal powder, etc.) properly selected can be added in order to match the color of the said molding with the tooth or to increase the mechanical strength or X-ray contrastability of the molding.
As mentioned above, the greatest characteristic of this invention is to employ the methacrylate contai
REFERENCES:
patent: 3345401 (1967-10-01), May
patent: 3715331 (1973-02-01), Molnar
patent: 3932181 (1976-01-01), Ray-Chaudhuri
patent: 4302376 (1981-11-01), Walkowiak et al.
patent: 4442239 (1984-04-01), Tsunekawa et al.
patent: 4499251 (1985-02-01), Omura et al.
patent: 4515930 (1985-05-01), Omura et al.
patent: 4525493 (1985-06-01), Omura et al.
patent: 4537940 (1985-08-01), Omura et al.
patent: 4539382 (1985-09-01), Omura et al.
patent: 4696955 (1987-09-01), Kuhlmann
Ishibashi Masaya
Tsunekawa Masayoshi
Clingman A. Lionel
Sankin Kogyo Kabushiki Kaisha
LandOfFree
Dental materials having X-ray contrastability does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Dental materials having X-ray contrastability, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dental materials having X-ray contrastability will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-464382