Abstract: For the production of a core for a root-filled prepared tooth the root canal (11) of the prepared tooth (10) is filled with an impression material (27) which is injected at the bottom of the root canal to successively fill the root canal from the bottom thereof and outwardly under expulsion of air therefrom. The injection is carried out with the aid of an injection needle (23) with an injection syringe cylinder (24) with piston (25) attached thereto, the cylinder being filled with said impression material and the injection needle serving as reinforcing element for the impression material, permitting extraction of the cast from the root canal after the impression material has set.

Abstract: In a method for the production of a gold core for a prepared root-filled tooth, the prepared root canal of the tooth is filled with a gasifiable setting impression material. A prefabricated core patrix, preferably of plastic, which consists of a core portion and a dowel portion, is inserted in the impression material which is allowed to set around the dowel portion for the formation of a core pattern. The core pattern is removed from the tooth and is embedded in a mold material which is heated for the gasification of the pattern, whereupon a gold core is cast in the mold formed after the gasification of the pattern.A core patrix for the production of a gold core for a prepared root-filled tooth is made as a single piece and consists of a core portion and a dowel portion which has a substantially smaller transverse dimension than the prepared root canal of the tooth. The core patrix is preformed and consists of a gasifiable material.

Abstract: The present invention provides an implant artificial denture comprising an intra-ossal implant implanted in the jaw, an elastic material fitted over the head of the intra-ossal implant, a crown of tooth and, if required, a receiver fitted over the head of the intra-ossal implant, wherein the receiver prevents the elastic material from falling off when chewing and masticatory pressure or shock is applied thereto and the elastic material absorbs the chewing and masticatory pressure or shock applied thereto to prevent lesion of the surrounding tissue, and further provides an implant artificial denture equipped with a chewing load limit sensing device incorporated therein, which aids in preventing lesion of the surrounding tissue.

Abstract: An endodontic implant comprises a smooth, non-threaded partially tapered shank having an integral crown portion on which an artificial tooth crown or denture is supported. The shank is implanted in the root canal of a tooth stump and through its apex into the jawbone of a patient. The shank is preferably provided with two tapered sections with an intermediate section of constant diameter and is dimensioned so as to occupy the whole of a root canal cavity when implanted therein. Preferably the implants are used in pairs, rigidly connected by a bar device to which a denture can be removably attached. The system anchors mobile teeth and prevents root resorption caused by instability.

Abstract: Disclosed is a dental arrangement and method for restoring broken teeth which require a crown and a retention post for securing the crown in a post hole formed in the tooth. The post hole is dimensioned to receive a first sleeve, which in turn is dimensioned to receive the retention post. By using the sleeve for confirming a desirable post hole size, and for centering the retention post during the making of the impression, a sufficient margin of error is built into the space between the post hole and the retention post to allow the placement of cement. A wax sealed second sleeve, with a short post therein, is used in making a die of the tooth.

Abstract: A dental post for build up of a tooth crown is characterized by an outer threaded structure having an upper cylindrical part and a lower tapered part and provided with a longitudinally extending vent. The post can be screwed or cemented into a reamed tooth root canal. The upper threaded part can accommodate a screw-on head.

Abstract: A post for attaching a tooth crown to a natural tooth root is disclosed which comprises a screw-threaded shank having a plurality of collars in screw-threaded engagement therewith, the collars being adjustable axially of the shank. A method of attaching a tooth crown using the post as aforesaid is also disclosed, the method including the steps of engaging the shank with a pre-prepared tooth root, locating the collars in a requisite relative disposition on the shank, preferably with a collar against the tooth root face providing a shaped head on the shank and within which the collars are at least partially embedded, and applying a crown to the said shaped head.

Abstract: A post broken off from a cap previously retained in human bony structure, such as a human tooth, is removed from a hole in the tooth within which the post has been retained, as by cement. The removal is effected by a hollow rotary drill having tooth cutters surrounding the post, said drill while rotating being urged into the hole until the cutters have released the post from the surrounding cement. Preferably an adjustable stop is provided within the drill to abut the outer end of the post when the cutters have reached the inner end thereof, to prevent damage to the root structure beyond the inner end of the post. The inner diameter of the drill closely fits the outer diameter of the post so that it acts as a guide for the cutters as they are urged into the hole within which the post is retained.