RU2815463C1 - Dental implant of anchoring system - Google Patents

Abstract

FIELD: medicine.

SUBSTANCE: invention relates to a dental implant of a dowel system. The implant includes a screw with three threads of the same pitch, made without annular grooves, namely the main thread of the spongy zone, a double thread of the cortical zone and an additional interturn thread of the spongy zone. At the lower end of the screw, a centring tip is formed to enter the porous ring, and at the upper end there is a gum former and an abutment. The implant also includes a dowel, which is an elastic-damping ring with through porosity and an internal diameter of 2 mm made of metal rubber containing titanium wire grade “ВТ 1-00” with a diameter of 0.01 mm with bone chips placed inside, obtained during the formation of the bone bed for the implant.

EFFECT: no deformation (tensile and compressive) stresses in the process of screwing in the implant, no likelihood of the formation of an empty cavity due to inaccurate positioning of the implant, no likelihood of voids forming at the points of contact between the bone and the thread cavity, obtaining sufficient primary stability of the implant in the cancellous bone, preventing twisting and uncontrolled advancement inside the cancellous bone are achieved.

1 cl, 2 dwg, 2 ex

Description

The invention relates to the field of medical technology and is intended for surgical, orthopedic dentistry, as well as maxillofacial surgery, and can be used in dental implantation and prosthetic operations as a dental implant. An implant is proposed, which includes: a) a screw with three threads of the same pitch, namely: the main thread of the spongy zone, a double thread of the cortical zone and an additional interturn thread of the spongy zone, b) an elastic-damping ring made of non-woven metal material with through porosity - metal rubber ( MP) - as a dowel. Since all threads are made with the same pitch and without annular grooves, during the process of screwing in the implant, deformation - tensile and compressive - stresses in the bone do not arise, which ensures sufficient primary stability of the implant in the cancellous bone. Additional threads between the turns of the spongy zone are designed to eliminate the possibility of voids forming at the point of contact between the bone and the cavity of the main thread. The lower end of the screw is a centering tip for entering the porous ring, eliminating the formation of an empty cavity due to inaccurate positioning of the implant, as well as the possibility of scrolling and uncontrolled movement into the cancellous bone; At the upper end there is a gum former and an abutment, which can be removable, which is not important.

Currently, manufacturing companies produce numerous versions of implants, the prototype of which was the flat and screw designs proposed by the founders of modern dental implantology L. Linkov (1964) and P.I. Branemark (1969). However, the variety of clinical situations, the tendency to expand indications for dental implantation, and the development of new methods of surgical interventions dictate the need to find and justify new modifications of dental implants.

The crown and root parts of each tooth, as well as the corresponding section of the jaw bone, have a unique and characteristic anatomical structure. This relationship is determined by topographic-anatomical conditions and patterns of functional loading in certain parts of the dentition. In addition, after tooth extraction, pathological and compensatory changes in bone tissue occur, which introduce additional features into the structure and structure of the alveolar processes of the jaws. For this reason, there cannot be a one-size-fits-all dental implant design. These circumstances encourage the creation of more advanced designs of dental implants, taking into account their installation in the alveolar processes of the jaws.

A number of dental implants are known from the prior art, differing in design features. For example, on the proximal and distal parts of the implant (patent RU 123317 U1, filing date 03/24/2011) a metric thread is made, the distal part of the implant is made in the form of a reverse concave saddle-shaped shape with a depth of 1.5 mm, in the proximal part of the implant there are 4 angular irrigation channels with a diameter of 0.35 mm, communicating with a ledge formed between the porous back-cone and proximal end parts, the porous back-cone element is made of titanium boride.

The dental implant (patent RU 122283 U8, application date March 29, 2012) consists of endosal and subperiosteal parts, the endoseal part of the cylindrical implant is made of titanium carbosilicide with through porosity, the pores of which are filled with lysates of bacteria of the genus Bacteroides, Fusobacterium, Peptostreptococcus, Peptococcus, Veillonella , Clostridium, Actinomyces; the subperiosteal part of the implant is made in the form of two L-shaped brackets, sliding in two-level parallel planes to form a U-shaped structure and fixed with a nut.

The screw dental implant (patent RU 161879 U1, application date 03/02/2012) has a thread on the intraosseous part with an angle between the lateral sides of the threaded protrusions in the intervals from 10° to 58°, with a thread stroke from 0.7 to 3.0 mm, thread profile height from 0.41 to 1.5 mm, the intraosseous part contains an internal cavity in the form of a conical or cylindrical seating surface and an internal thread from 1.8 mm to 2.5 mm, on the internal seating surface there are recesses that form polygonal or elliptical shapes in the section plane with protruding peaks, in the end part the implant is made with a lower thread profile and a reduced internal diameter of the thread, compared to the main part of the implant, the outer diameter of the implant thread is from 4.0 mm to 6.5 mm, and the internal diameter is from 2. 0 mm to 4.0 mm. At the end part, the implant is made with a smooth lowering of the thread profile and a decrease in the internal diameter of the thread, and the interface between the implant and the instrument for inserting the implant is made in the form of recesses (slots), forming polygonal figures in the section plane with protruding vertices (corners). At the end part of the implant and, as an option, also (or) at the cervical part, longitudinal or spiral grooves with a cutting edge are made. The intraosseous part usually contains a cervical conical or cylindrical part with a thread and an apical conical or cylindrical part with a thread, while the cervical and apical parts contain different threads that differ in thread pitch, and (or) profile height, and (or) contour angle.

A dental implant (patent RU 2624173 C2, application date September 28, 2015) consists of an intraosseous porous cylindrical sleeve made of metal rubber, a metal rod placed inside the cylindrical cavity of the sleeve, and a crown attached to a metal rod, characterized in that the outer diameter of the sleeve is made of metal rubber is larger than the diameter of the smooth blind hole in the intraosseous area in which the sleeve is placed, and the sleeve is made of metal rubber, elastic in both the radial and axial directions, and the metal rod consists of two sections, in the section with which it is tightly sealed without gaps a bushing made of metal rubber, one, two or more annular flanges are made, from which the flats are removed from two opposite sides, and on the other free section along its entire length a thread is cut, or a metal rod is made in such a way that the thread is made along the entire length of the rod, and the flats on two opposite sides are removed only on the section of the rod embedded in a sleeve made of metal rubber, or this section of the metal rod is made like a fitting for a rubber hose, with several cones with a cone angle of 15°, and the flats are removed on two opposite sides from all cones, either two or three.

The disadvantages of the listed inventions include: 1) the occurrence of deformation (tensile and compressive) stresses during the process of screwing in the implant; 2) the likelihood of the formation of an empty cavity due to inaccurate positioning of the implant; 3) the likelihood of voids forming at the points of contact between the bone and the thread cavity; 4) the impossibility of obtaining sufficient primary stability of the implant in cancellous bone; 5) there is a danger of scrolling and uncontrolled movement into the cancellous bone.

The purpose of the invention is a dental implant that is devoid of the listed disadvantages, while maintaining all the advantages of known design solutions.

This goal is achieved due to the fact that the proposed dental implant of the dowel system includes a screw with three threads of the same pitch, made without annular grooves, namely: the main thread of the spongy zone, a double thread of the cortical zone and an additional interturn thread of the spongy zone (Fig. 1 ), at the lower end of which a centering tip is formed to enter the porous ring, and at the upper end there is a gum former and an abutment; and a dowel, which is an elastic-damping ring (Fig. 2) with through porosity and an internal diameter of 2 mm made of metal rubber containing titanium wire grade VT 1-00 with a diameter of 0.01 mm and bone chips placed inside, obtained during the formation of the bone bed under implant Since all threads are made with the same pitch and without annular grooves, when screwing in the screw, deformation - tensile and compressive - stresses do not arise in the bone, which is especially important for the third type of bone. Additional threads between the turns of the spongy zone are designed to eliminate voids at the point of contact between the bone and the cavity of the main thread. The lower end of the screw is a centering tip for entering the porous ring, eliminating the formation of an empty cavity; at the upper end of the screw there is a gum former and an abutment, which can be removable, which is not important.

The screw included in the implant was made in two ways: a) - turning, by processing; b) - knurling with profiled rollers.

For the manufacture of rings from MP, titanium wire of grade VT 1-00, with a diameter of 0.01 mm, was used. After winding the wire into a spiral with a diameter of 1.0 mm in a special machine, 0.200 ± 0.015 mg was weighed out. The required amount of spiral was passed through the calibration hole to a pitch equal to the diameter of the spiral, which was 1.0 mm. A blank was made from the spiral stretched in this way. The spiral was laid in the form of a “mat” on a rubberized table. Bone filings (chips) obtained during the formation of the bone bed for the implant were placed inside the wire spiral.

For cold pressing, a special metal mold was made, consisting of a matrix in the form of a hollow cylinder with an internal diameter of 3.3 to 4.0 mm. A metal rod with a diameter of 2 mm was used to form the inner hole of the ring. The mold punch was a hollow sleeve with an internal diameter of 1.6 mm and an external diameter of 3.3; 3.5;4.0 mm.

The resulting wire “mat” with autologous bone sawdust obtained during drilling was wound onto the metal rod of the punch. The workpiece was inserted into the matrix. The punch was put on a metal rod and the entire structure was placed on the press plate. A pressure of 5±1 MPa was created in the press. Press effort was selected empirically. Only with this force were pores with a diameter of 120 to 200 μm and a porosity of 70 ± 10% obtained in the ring.

As a result of cold pressing, MP obtained hollow rings with an internal diameter of 2 mm and an external diameter of 3.3; 3.5; 4.0 mm (Fig. 2). The MP ring in the implant acted as a dowel.

Clinical example 1.

Patient A., 37 years old, sought outpatient help for dental restoration. A year ago, tooth 2.4 was removed due to chronic granulating periodontitis. After an X-ray examination, the patient was asked to restore her dentition using a dental implant dowel system developed by the author of this application. Under infiltration anesthesia with a 2% articaine solution, a trapezoidal mucoperiosteal flap was cut out on the alveolar process in the projection of the extracted tooth 2.4. Using a raspator, the mucoperiosteal flap was separated and moved outward. Using a set of standard cutters, a bone bed was formed for the dental implant. A ring of MP was advanced to the bottom of the formed bone bed using a special implant driver. The pores contained shavings from autologous bone, which promoted the inward growth of blood vessels and enhanced the process of integration of the implant into the jaw. Possessing elastic properties and microporosity, the ring is rigidly fixed in the cancellous bone, thereby creating conditions for good primary stabilization of the implant of our design as a whole. As experimental studies on animals have shown, bone subsequently grows into the pores of a cylinder made of non-woven titanium material, which ensures osseous integration of the implant and surrounding tissues. Next, using an implant driver, a spacer pin was screwed into the bone bed, which, due to a system of threads, was rigidly embedded in the dense cortical part of the jaw. At the same time, the tail part of the screw, falling into the center of the ring made of non-woven titanium material with through porosity, expanded it, thereby creating additional force for stable fixation of the tail part of the screw in the cancellous bone. The mucoperiosteal flap was placed in place and tightly sutured with polyamide thread.

The wound healed by primary intention, the sutures were removed on the 10th day. After 4.5 months, the implant was opened. A healing abutment was installed. After 4 months, orthopedic treatment began.

Clinical example 2.

An orthopedist's extract from the outpatient card of patient G., born in 1963. The patient complained of an aesthetic defect and the inability to chew food. Objectively: upon external examination, there is no facial asymmetry, the skin is of normal color, nasolabial, folds are moderately expressed, consistent with gender and age. The mouth opens freely, painlessly. Dowel system implants are installed in the projection of missing teeth 1.6, 1.5, 2.4, 2.5, 2.6, 3.4, 3.5, 3.6.

The mucous membrane in the peri-implant area is without signs of inflammation, the implants are stable. The mucous membrane of the oral cavity is pale pink in color, moist without rashes.

Diagnosis: Partial absence of teeth on the upper and lower jaws. Kennedy class 2; loss of chewing efficiency 76%. Etiofactor: caries and its complications.

Treatment: in 1 visit, an Elite HD+ impression was taken using the open tray method from the upper and lower jaws. Registration of central occlusion. 2nd visit: fitting templates for implants 1.6, 1.5, 2.4, 2.5, 2.6, 3.4, 3.5, 3.6. 3rd visit: fitting of frames of metal-ceramic prostheses supported on 1.6, 1.5, 2.4, 2.5, 2.6, 3.4, 3.5, 3.6 implants. Color selection A3 by Vita Cl. 4th visit: fitting of combined prostheses supported on implants 1.6, 1.5, 2.4, 2.5, 2.6, 3.4, 3.5, 3.6.

5th visit: fitting of combined dentures supported by implants 1.6, 1.5, 2.4, 2.5, 2.6, 3.4, 3.5, 3.6 and their fixation with FujiI cement. Recommendations are given.

Claims (1)

A dental implant of a dowel system, including a screw with three threads of the same pitch, made without annular grooves, namely the main thread of the spongy zone, a double thread of the cortical zone and an additional interturn thread of the spongy zone, at the lower end of which a centering tip is formed for entering the porous ring, and on the top there is a gum former and an abutment; and a dowel, which is an elastic-damping ring with through porosity and an internal diameter of 2 mm made of metal rubber containing titanium wire grade VT 1-00 with a diameter of 0.01 mm with bone chips placed inside, obtained during the formation of the bone bed for the implant.