Abstract:
A medical/dental apparatus utilizing the properties of shape memory materials to variably control the spatial relationship between two or more elements having portions which are proximately disposed and overlapping relative to one another. Another portion of each element is connectable to part of a patient's body.
Abstract:
A device for attaching a member that replaces a part of a set of teeth, wherein the device has a pin to be implanted in a jawbone and a coupling pin with a ball-and-socket joint disposed between the coupling pin and the implantation pin. The ball and/or the socket of the joint is made of a memory material. The memory position is such that at body temperature pivotal motion of the ball-and-socket joint can simply be brought into a desired position. Thus, the coupling pin can be brought into any desired position, virtually independently of the orientation of the implantation pin in the jaw, so that the dental-replacement member can be fitted readily without any tension arising therein.
Abstract:
Dental crowns and bridges are made from thermoplastic molding compositions which are a mixture of thermoplastic material (for example, polycaprolactone), a free-radically polymerizable resin (for example, a urethane diacrylate oligomer), and free-radical initiator (for example, a visible-light cure photoinitiator). The mixture is solid at 38.degree. C., has a melting or softening point that comfortably can be withstood by oral tissues, and can be imprinted with a heat-stable custom shape memory and semi-thermoplastic properties by shaping the composition to a desired shape and then causing or permitting the resin to undergo polymerization.
Abstract:
A new multi-strand orthodontic arch wire comprises a plurality of wire strands of superelastic shape recovery metal alloy wrapped helically parallel to one another along the length of the wire, the ratio of the longitudinal pitch P of the wire to the external diameter D of the wire being between six and twelve. Such a wire is able to slide more freely in the bracket slots, and is less likely to breakage, than the short pitch wires previously used. A wire with a hollow central core, can also operate as a compression spring by frictionally engaging it with adjacent orthodontic elements, such as brackets, and arranging that its strands are spread radially apart from a neutral configuration, or it can operate as a traction spring by arranging that its strands are closed radially inward from a neutral configuration, the spring action being produced by the urge of the strands to return to the neutral configuration. Cored wires can act as a compression spring, but not as a traction spring. Partial cores strands can be provided to localize the spring action to specific parts of the wire. The wires can be provided with crimpable end members. The shape recovery metal alloy can be any one of nickel/titanium; nickel/titanium/copper; copper/zinc/aluminum; copper/zinc/aluminum/manganese; copper/aluminum/nickel; and copper/aluminum/nickel/manganese.
Abstract:
Transpalatal orthodontic appliances are disclosed which utilize a shape-memory or superelastic alloy member as the force-supplying member of the device. Suitable alloys include the nickel-titanium (NiTi) alloys, the titanium-molybdenum alloys (TMA), and any other alloy composition which possesses superelastic or shape-memory characteristics. The alloy composition may preferably have a working rang of at least about 30% and a modulus of elasticity not exceeding about 15.times.10.sup.6 psi.
Abstract:
A dental implant comprising an artificial root which is embedded in a jaw bone and a post to which an artificial tooth is attached, wherein a stress absorbing member made of a super elastic material is provided in at least a part of the implant between the artificial root and the post. Preferably, a stress absorbing system consisting of a super elastic material member and a polymeric material member is employed.
Abstract:
An orthodontic teeth alignment correction wire element made of an alloy represented by the chemical formula of Ti.sub.a Ni.sub.b-c C.sub.c, wherein a+b=100, b=50-52, c=0.25-5.0, or an alloy represented by the chemical formula of Ti.sub.a Ni.sub.b-c-d C.sub.c X.sub.d, wherein X is at least one element selected from V, Cr, Fe, Nb, Ta, W, and Al, wherein a+b=100, b=50-52, c=0.25-5.0, d=0.25-2.0, and exhibits pseudoelasticity at the natural human body temperature. The wire has different recovery forces at different sections therealong by heat treating those sections at controlled temperatures of 400.degree.-600.degree. C. and for controlled time periods of 10-150 minutes and thereafter reheat treating them. An orthodontic coil is made of each of the above-described alloy wires for correction of mismatch of the upper and the lower jaws.
Abstract:
A dental endosseous implant having a generally cylindrical shape, which includes a leg portion embedded in an alveolar bone to form an artificial tooth root, and a head portion extending from one end of the leg portion to form a support upon which an artificial tooth is mounted. The implant is at least partially made of a metallic material having a thermal shape memory effect of deformation, which causes the leg portion to be bent with respect to the head portion in response to a variation of temperature of the implant after insertion of the leg portion into the alveolar bone.
Abstract:
Medical devices which are currently proposed to use elements made from shape memory alloys may be improved by the use of stress-induced martensite alloy elements instead. The use of stress-induced martensite decreases the temperature sensitivity of the devices, thereby making them easier to install and/or remove.
Abstract:
Proposed is a retainer and a method for manufacturing the retainer. The retainer has a body which is in close contact with a tooth arrangement and which is formed of a shape memory alloy material. The body is manufactured by being laser cut from a base material of the shape memory alloy material on the basis of 3D scanning data of the tooth arrangement and then a width thereof is modified. The method includes a process of acquiring three-dimensional data of the tooth arrangement, a data processing process of generating processing line data on the basis of the scanning data, a laser cutting process of manufacturing a body forming part by laser cutting the shape memory alloy material, and a width modification process of thermally treating the body forming part after expanding or reducing and fixing the body forming part so that the width thereof is widened or narrowed.