Abstract:
Root canal abutment devices and methods which facilitate the adjustment or removal of an oral appliance, e.g., a crown or bridge, from a reconfigurable abutment assembly are described. The adjustable abutment assembly may be secured within a pulp chamber of a pre-existing tooth. The abutment assembly has a projecting abutment portion with one or more shape memory alloy sleeves or plates or elements extending along the abutment. Each of the sleeves has a length with at least one curved or arcuate portion. Energy may be applied to the elements such that the arcuate portion flattens to allow for the oral appliance to be placed thereupon while removal of the energy allows the elements to reconfigure into its curved configuration thereby locking the oral appliance to the abutment. Removal of the oral appliance may be effected by reapplication of energy to the elements.
Abstract:
Orthodontic appliances for correcting teeth irregularities and for retaining the position of teeth are disclosed. According to an aspect, an orthodontic appliance may include an arch component configured to engage one of teeth and gums of a patient. Further, the orthodontic appliance may include a spring having a teeth engaging portion and an anchor portion. The teeth engaging portion may be shaped to engage the incisors of the patient. The anchor portion may be attached to the arch component.
Abstract:
An orthodontic appliance includes a portion made of a shape memory alloy having a base alloy composition of at least two different metallic elements and a treated region having an alloy composition that is depleted in at least one of the metallic elements. The base alloy may include a nickel titanium alloy (NiTi), a copper chromium nickel titanium alloy (CuCrNiTi), or a copper aluminum nickel (CuAlNi) alloy. The treated region may be depleted in at least one of copper, aluminum, nickel, and titanium relative to the base alloy composition by exposing the base alloy to a source of energy. The base alloy composition has a first austenitic finish temperature and the treated region has an austenitic finish temperature that may be different than the first austenitic finish temperature. The treated region may form a part of an archwire, a stop, a hook, a crown, a band, or an orthodontic bracket.
Abstract:
The invention relates to a method for manufacturing a titanium alloy having superelastic properties and/or shape memory for biomedical use, which comprises the steps of: preparing an ingot by melting the various metals that form the desired alloy in a vacuum; optionally homogenizing the ingot in a vacuum by high-temperature annealing (higher than 900° C.); first quenching; mechanical shaping (rolling, drawing, machining or the like); heat treatment for redissolution in beta phase beyond the beta transus temperature (until a second temperature and then maintaining same for a certain time); and second quenching; characterized in that said heat treatment phase is carried out in a gaseous atmosphere and also constitutes a surface treatment suitable for forming on the surface a layer of nitride, carbonitride, oxide, oxynitride or the like.
Abstract:
Methods for modifying a physical characteristic of finished endodontic instruments made from one or more superelastic alloys is described which include heat treating one or more finished endodontic instruments in a salt bath for a specific time (e.g., from about four hours to about six hours), at a specified temperature (e.g., from about 475° C. to about 550° C.), and preferably at a specified pH range.
Abstract:
A root canal instrument includes a twisted strip having a titanium-nickel alloy or a plastics material. The strip has a cross-section having three exterior surfaces or four exterior surfaces. A coating is disposed on at least one exterior surface, the coating includes abrasive particles. A method of making the root canal instrument includes making a basic plate having a thickness of less than one millimeter, coating the basic plate with a coating having the abrasive particles; dividing the basic plate into longitudinally extended strips, twisting the strip to form a root canal drill bit having a cutting edge with abrasive particles disposed on the cutting edge.
Abstract:
Dental retention systems which facilitate the adjustment or removal of an oral appliance, e.g., a crown or bridge, from a reconfigurable abutment assembly are described. The adjustable abutment assembly may be secured to an anchoring implant bored into the bones within the mouth. The abutment assembly has a projecting abutment portion with one or more shape memory alloy compression plates or elements extending along the projecting abutment portion. Each of the plates has a length with one or more straightened portions and with at least one curved or arcuate portion. Energy may be applied to the elements such that the arcuate portion self-flattens to allow for the oral appliance to be placed thereupon while removal of the energy allows the elements to reconfigure into its curved configuration thereby locking the oral appliance to the abutment. Removal of the oral appliance may be effected by reapplication of energy to the elements.
Abstract:
A method of making articles made of shape memory alloys having improved fatigue performance and to methods of treating articles formed from shape memory alloy materials by pre-straining the articles (or desired portions of the articles) in a controlled manner so that the resultant articles exhibit improved fatigue performance. The shape memory articles are preferably medical devices, more preferably implantable medical devices. They are most preferably devices of nitinol shape memory alloy, most particularly that is superelastic at normal body temperature. The pre-straining method of the present invention as performed on such articles includes the controlled introduction of non-recoverable tensile strains greater than about 0.20% at the surface of a desired portion of a shape memory alloy article. Controlled pre-straining operations are performed on the shape-set nitinol metal to achieve non-recoverable tensile strain greater than about 0.20% at or near the surface of selected regions in the nitinol metal article. The pre-straining operations result in a significant increase in fatigue life of the selectively treated regions and an overall improvement in the fatigue performance of the device.
Abstract:
A fiber tip fluid output device is provided for holding a fiber tip in an electromagnetic energy cutting apparatus and for directing water particles over a radiation delivery end of the fiber tip. The fiber tip fluid output device includes a generally cylindrical body having an outer surface, a proximal end, a distal end, and a lumen extending between the proximal end and the distal end. The lumen is sized and shaped to accommodate a fiber tip therethrough so that the fiber tip extends through the lumen from the proximal end to the distal end of the generally cylindrical body. The fiber tip fluid output device further includes a plurality of apertures extending around the generally cylindrical body, with each of the apertures of the plurality of apertures fluidly connecting the outer surface to the lumen. Fluid is mixed around the cylindrical body, before entering the lumen through the plurality of apertures for additional mixing. The mixed fluid is then output from the lumen of the fiber tip fluid output device onto the fiber tip, for subsequent interaction with electromagnetic energy in an interaction zone above a target surface.