Abstract: Ophthalmic lenses incorporate multifocal properties for the purpose of slowing, retarding, controlling or preventing myopia development or progression, correcting presbyopic vision or allowing extended depth of focus. The lens has electronically controlled adjustable focus where the change in focus oscillates so rapidly that it is imperceptible to human vision.

Abstract: Ophthalmic lenses incorporate multifocal properties for the purpose of slowing, retarding, controlling or preventing myopia development or progression, correcting presbyopic vision or allowing extended depth of focus. The lens has electronically controlled adjustable focus where the change in focus oscillates so rapidly that it is imperceptible to human vision.

Abstract: An implantable bone prosthesis includes portions of two different materials which interfit with each other to form a unitary article having hard wear surface portions and strong, stiff portions for structural support. These portions are preferably formed of ceramic and of metal, respectively. The prosthesis is formed by making a multiply connected ceramic wear surface element having openings or passages therethrough, and casting the remainder of the prosthesis extending in the openings to form a mating or dendritic support or a frame interdigitated and interlocked with the ceramic wear surface. The frame may be shaped so that it contracts along a direction of shrinkage, as the casting cools, without binding against the ceramic body. In a spherical shell, such as used for the weight-bearing acetabular shell or ball joint of a hip, this is achieved with short, radially-directed interlock elements.

Abstract: An implant component adapted for bone attachment or replacement is molded from a feed stock which contains a soluble major binder, a backbone binder and structural powder material. After the feed stock is injection molded to form a compact or preform, the major binder is removed from the green article, leaving a structure of interconnected porosity or texture, while the backbone binder remains until the component is sintered. Preferably, the amount of the soluble binder is set to increase the porosity, or reduce the stiffness, of the finished component, thus introducing a biocompatible or growth-enhancing level of porosity or stiffness during the molding process. In further or alternative embodiments, the component may be injection molded onto or about a solvent-leachable spacer preform and/or adjacent to another injected or molded portion of the component which serves as a structural body, frame or shell.

Abstract: A bone prosthesis has a growth enhancement coating recessed in and protected by its surface topography. The topographic features define gaps under a few millimeters which are readily spanned by new bone growth, while the features protect the coating from abrasion or physical damage. The topographic features substantially surround the coated regions, and prevent migration of flakes spalled during implantation or microparticles shed by the coating as it is resorbed or incorporated in new bone over time. In a preferred embodiment, edge features cast in the surface of a metal prosthesis include dovetail, undercut or skewed faces which firmly interlock with newly-growing bone to form a strong and shear-free, substantially rigid attachment. The prosthesis may be cast in a mold having a complex surface interlock texture, and these molds may be mass produced by an iterative three-dimensional printing technique to build each mold up in layers in the form of a suitable casting negative.

Abstract: An implantable article having on at least a portion of its exterior surface an integral, as-cast macrotextured surface with macropores having undercut edge profiles. A complex macrotextured surface is provided by forming a casting mold so that the mold has complementary macrotextured surface features formed by three-dimensional printing techniques, and casting a molten metal within or in contact with the casting mold to form the implantable article. In a hybrid process, one or more printed surface mold plates are attached by hand, or in a wax molding process, to a simpler wax preform, and an investment is made in which the plates are incorporated into the investment mold. A casting is then made, with each preform yielding one cast article, and the incorporated plate forming the desired surface macrotexture on a region of the cast article.

Abstract: An acetabular trial insert is provided in which the appropriate anteversion angle of the acetabular cup of a hip prosthesis may be determined automatically by placing an inner cup within an outer cup and providing a mechanism which will hold the inner cup in position after the trial has been reduced and the hip rotated through an intended range of motion.

Abstract: An implantable bone prosthesis, such as an acetabular shell, includes a bone engaging region that is made from a cast metal or metal alloy and an articulation surface that is formed of a ceramic material or a metal that is permanently attached to the metal bone engaging region. The bone engaging region of the prosthesis preferably includes a dampening mechanism to absorb some of the loading forces communicated to the acetabular cavity. The bone prosthesis is formed by a casting process from casting molds that are prepared using a three dimensional printing technique.

Abstract: An implantable bone prosthesis includes portions of two different materials which interfit with each other to form a unitary article having hard wear surface portions and strong, stiff portions for structural support. These portions are preferably formed of ceramic and of metal, respectively. The prosthesis is formed by making a multiply connected ceramic wear surface element having openings or passages therethrough, and casting the remainder of the prosthesis extending in the openings to form a mating or dendritic support or a frame interdigitated and interlocked with the ceramic wear surface. The frame may be shaped so that it contracts along a direction of shrinkage, as the casting cools, without binding against the ceramic body. In a spherical shell, such as used for the weight-bearing acetabular shell or ball joint of a hip, this is achieved with short, radially-directed interlock elements.

Abstract: An implantable article having on at least a portion of its exterior surface an integral, as-cast macrotextured surface having pores with undercut edge profiles is provided. The integral, as-cast macrotextured surface is able to be formed on the implantable articles by a modified casting process. As part of a casting process, positive models of the articles to be cast, or parts thereof, are formed by stereolithographic techniques. Cavities or molds, representing negative images of the articles to be cast, are then formed by encasing one or more models in a refractory material. The positive models are then extracted by heating and thus melting the material from which they are made. Thereafter, molten casting material can be poured into the resulting mold to obtain the implantable articles.

Abstract: An implantable article having on at least a portion of its exterior surface an integral, as-cast macrotextured surface with macropores having undercut edge profiles. A complex macrotextured surface is provided by forming a casting mold so that the mold has complementary macrotextured surface features formed by three-dimensional printing techniques, and casting a molten metal within or in contact with the casting mold to form the implantable article. In a hybrid process, one or more printed surface mold plates are attached by hand, or in a wax molding process, to a simpler wax preform, and an investment is made in which the plates are incorporated into the investment mold. A casting is then made, with each preform yielding one cast article, and the incorporated plate forming the desired surface macrotexture on a region of the east article.

Abstract: The present invention provides a cement delivery system having concentric lumens that terminate in openings at the distal end of the delivery system for providing a selected application of two or more cement types or compositions that vary from the middle of a bone cavity to the circumference of the bone cavity. The invention also provides a method for applying cement into a bone cavity to provide a gradient of materials within the bone cavity from the middle point or center of the bone cavity to the circumference of the cavity.

Abstract: An implantable article having on at least a portion of its exterior surface an integral, as-cast macrotextured surface having pores with undercut edge profiles is provided. The integral, as-cast macrotextured surface is able to be formed on the implantable articles by a modified casting process. As part of a casting process, positive models of the articles to be cast, or parts thereof, are formed by stereolithographic techniques. Cavities or molds, representing negative images of the articles to be cast, are then formed by encasing one or more models in a refractory material. The positive models are then extracted by heating and thus melting the material from which they are made. Thereafter, molten casting material can be poured into the resulting mold to obtain the implantable articles.

Abstract: Implantable articles, such as bone prostheses, are prepared by casting techniques and have incorporated therein fluid communicating passageways. The internal fluid communicating passageways convey synovial fluid from a joint space to the articulation surface of an artificial joint. The presence of synovial fluid at the articulation surface provides sufficient lubricity to the joint and enables artificial joints to utilize metal/metal, metal/ceramic, and ceramic/ceramic articulation couples without the need for a low friction polymeric lining material. Accordingly, artificial joint components formed according to the present invention are less likely to develop wear debris. The implantable articles are formed by a casting process from casting molds that are prepared using a three dimensional printing technique.

Abstract: An implantable article having on at least a portion of its exterior surface an integral, as-cast macrotextured surface with macropores having undercut edge profiles. A complex macrotextured surface is provided by forming a casting mold so that the mold has complementary macrotextured surface features formed by three-dimensional printing techniques, and casting a molten metal within or in contact with the casting mold to form the implantable article. In a hybrid process, one or more printed surface mold plates are attached by hand, or in a wax molding process, to a simpler wax preform, and an investment is made in which the plates are incorporated into the investment mold. A casting is then made, with each preform yielding one cast article, and the incorporated plate forming the desired surface macrotexture on a region of the cast article.

Abstract: Implantable articles, such as bone prostheses, are prepared by casting techniques and have incorporated therein fluid communicating passageways. The internal fluid communicating passageways convey synovial fluid from a joint space to the articulation surface of an artificial joint. The presence of synovial fluid at the articulation surface provides sufficient lubricity to the joint and enables artificial joints to utilize metal/metal, metal/ceramic, and ceramic/ceramic articulation couples without the need for a low friction polymeric lining material. Accordingly, artificial joint components formed according to the present invention are less likely to develop wear debris. The implantable articles are formed by a casting process from casting molds that are prepared using a three dimensional printing technique.

Abstract: An implantable bone prosthesis, such as an acetabular shell, includes a bone engaging region that is made from a cast metal or metal alloy and an articulation surface that is formed of a ceramic material or a metal that is permanently attached to the metal bone engaging region. The bone engaging region of the prosthesis preferably includes a dampening mechanism to absorb some of the loading forces communicated to the acetabular cavity. The bone prosthesis is formed by a casting process from casting molds that are prepared using a three dimensional printing technique.

Abstract: A process for making a composite stem for a prosthesis by providing a tapered metal core with a predetermined cross section and a composite shell having a tapered cavity having a cross sectional configuration to receive the metal core. Adhesive is applied to the metal core and the core is placed in the cavity and pressure is applied along the axis of the metal core toward the smaller end of the core to force the core against the composite shell and heat is applied with the pressure to bond the composite shell to the metal core.

Abstract: A composite stem for a prosthesis, particularly a hip prosthesis, including a metal core and a fiber reinforced composite shell surrounding the core to provide modulus values that are similar to bone. The composite shell is preferably composed of braided fibers and a thermoplastic resin. The stiffness of the prosthesis can be varied along the length of the stem. The metal core contributing between 5 and 25 percent of the total flexural stiffness of the stem.

Abstract: An osteal prosthetic component of a prosthetic joint and a method of implanting an osteal prosthetic component in the medullary canal of a bone are disclosed. The osteal prosthetic component includes a stem for disposition within a medullary canal of a bone and a fluted wedge portion extending from the stem. The fluted wedge has wedge portions which define at least one flute between the wedge portions. An interference fit is formed between the wedge portions and the bone during implantation of the stem into the medullary canal. Movement of the osteal prosthetic component relative to the bone is thereby sufficiently limited to allow tissue growth into a tissue-ingrowth portion at the surface of the stem to substantially prevent micromotion of the stem relative to the bone.