WO2013097044A1

WO2013097044A1 - Prosthetic retention system for edentulous patients, formed by a prefabricated bar and two implants

Info

Publication number: WO2013097044A1
Application number: PCT/CL2012/000053
Authority: WO
Inventors: Jorge Antonio JOFRÉ ARAYA
Original assignee: Universidad De Concepcion
Priority date: 2011-12-28
Filing date: 2012-09-13
Publication date: 2013-07-04

Abstract

The invention relates to a prosthetic retention system for edentulous patients, formed by a prefabricated bar and two implants. According to the invention, the aforementioned bar is formed by a tubular central part having a round or ovoid-like cross-section and two hollow caps at the ends thereof, and the implants are formed by a single part comprising an upper area that is connected to the bar and a lower area forming the section that is inserted into the bone of the patient.

Description

A PROTEST RETENTION SYSTEM FOR DESENTED PATIENTS COMPOSED BY A BAR

PREFABRICATED AND TWO IMPLANTS Technical Sector

The technology is oriented to the dental area, more specifically to a prosthetic retention system composed of a prefabricated bar and two implants for toothless patients.

Previous Technique

Today, more than 30% of adults over 65 are totally toothless, which affects their self-esteem and quality of life. Bone-integrated implants have solved this problem, considering two mandibular implants as the minimum standard of treatment for these patients. However, due to its high cost and complexity, trauma and surgical risks are added to which patients must undergo, which has made it impossible to use these systems as routine treatment in the world's public health systems, which decreases the effectiveness of rehabilitative treatments and the use of resources allocated for this benefit.

In the market there are small diameter dental implants, which have been indicated in the treatment of toothless adults because they are not very invasive, do not require incisions, or large bone volume, which avoids surgical trauma, also because they are low cost and simplicity. . Unfortunately, it is these same factors that generate the disadvantages of this system, since when using a blind technique, without raising the gum, there is a great risk of inserting the implant out of the bone tissue. In addition, its small diameter seems to violate all the biomechanical principles that are known to ensure long-term integration of implants into bone tissue. These obvious risks, coupled with the absence of scientific evidence, require the implantation of conventional diameter implants (over 3.5 mm) with the known trauma problems for the patient, complexity and cost.

The mandibular implants have different options for retaining the prosthesis, being a metal bar manufactured individually to be screwed onto the implants, which provides greater long-term stability and less repair costs; these are used with conventional implants with a minimum diameter, since they use screws that are fixed in an inner thread of the implants. The implants, minimally invasive, of very small diameter cannot use this type of bars because they do not have a system of internal fixing screws. These bars must be made in laboratories, compromising several stages, time, technological capacity and costs that border the US $ 500. To this is added the successive appointments of the patient to complete the treatment in periods ranging from a couple of weeks to months

There is a prefabricated SFI-Bar ® bar from the company CENDRES + MÉTAUX (Switzerland), which has a system of movable rails and screws at its ends that allows it to adapt to the position of the implants that are previously inserted. This technology is indicated for immediate function, however, sutures and delicate tissue management at the time of conventional implant surgery, added to the impossibility of keeping the implants in centered positions and the large size of this bar with its screws, it makes difficult the clinical work to adapt the prostheses immediately, requiring laboratory stages for prosthetic adaptation.

Therefore, it is necessary to develop technologies aimed at solving these types of problems.

Disclosure of the Invention

The present technology corresponds to a prosthetic retention system useful for toothless patients, comprising a prefabricated bar and two implants. For a better understanding of innovation, Figures 1 and 2 will be taken as a reference.

The bar (1) is composed of a tubular centerpiece (2) preferably made of a titanium alloy or surgical steel, which has a round cross section or similar to an ovoid between 1 and 2 mm in diameter. At its ends it has two hollow capsules (3) located at a distance between 10-25 mm between its centers, preferably 1 1 mm, with a conical shape slightly larger than the implant heads, which may have a groove ( 4) on one or both sides. Said grooves (4) occupy part or all of a wall of the bar (1) leaving partially or totally open one or both sides, to allow one of the ends to be opened in case of needing to remove the bar and to facilitate the flexibility of this area by insertion moment On the other hand, the implants (5) are made in one piece with an alloy preferably of TiAIV, which can be heat treated to improve its mechanical properties. The implants are composed of an upper area (6) called the implant connection, consisting of 2 hexagonal pieces (9) joined by a convex central part (8) that allows the O-Ring to be retained if the implant is used individually . The upper hexagonal part, corresponding to the implant head, has rounded angles in its contour (7); and the lower hexagonal piece presents flat faces that match those of the implant head, which serve as an anti-rotational element to insert the implant. At the base of the upper zone is a bevel (10) useful to allow the adjustment of the capsules of the bar (3).

The lower area of the implant corresponds to the part that is introduced into the body, and includes a smooth cylinder-conical section of 1, 5 to 4 mm in diameter in contact with the gum (12), and a rough section in contact with the bone tissue (13) that is formed by an elongated body 10-20mm in length, with a conical cylinder-shaped diameter between 1-2mm, with a double thread thread that increases its width as it moves away from the tip of the implant

The system is completed by inserting the rod (1) into the upper end (6) of the implants. This comes under pressure and remains retained when it passes to the greater diameter of the head (7) of the implants, adjusting to the bevel of the base (10) so that a unique system (11) is formed avoiding the use of cement or screws.

The head (7) of the implant, in addition to allowing the capsule (3) to be fixed, the convex zone that connects the hexagonal parts can be used for the retention of a prosthetic retention O-Ring, in case of using the implant individually Without the bar

For a correct operation of the system it is suggested to use a guide clamp to position the implants in parallel, at the same height and centered on the bone.

This system does not require special fixing screws; It provides long-term stability optimizing your clinical behavior from insertion, facilitates immediate function, and is used without laboratory stages. The bar (1), at the same time, allows the best prosthesis stabilization option; It reduces long-term prosthetic complications and the associated costs. It allows its removal if necessary, without the need to change the implants. The benefits of this integrated system are:

• minimum instruments and equipment for implementation;

• minimal components, simple, safe and precise;

• Biomechanical improvement through a stabilization bar;

• minimally invasive, minimal surgical risks;

· Immediate function;

• no incisions required, no period of convalescence;

• decrease in the cost of treatment; Y

• clinically validated in the long term in a representative sample of the national population, user of public health services. Application examples

In order to provide a long-term treatment of less trauma, complexity and cost for toothless adults, an integrated system was developed to stabilize dentures, consisting of two implants and a prefabricated prosthetic bar. For proper operation, instruments such as a 3D positioning guide-clamp and a telescopic insert support were also used. To verify the functionality of the technology, the surgical procedure is detailed below (see Figure 3):

First, infiltrative local anesthesia was applied, and the thickness of bone tissue in the area to be implanted was measured using a guide clip (1). This guide-clamp allowed to orientate the perforations for the implants in a minimally invasive way, without the need for a gum flap, which were made with 1 mm (2) drills, centered on the jaw and in a thick area minimum bone of 2 mm. Then the first implant (3) was inserted and the clamp was repositioned resting on the head of the latter and a second perforation was performed. Next, a telescopic insertion support (4) was introduced in the head of the first implant and the second implant (3) was inserted. The heads of both implants were adjusted to equal height and a distance of 1 1 mm. The prosthetic bar was inserted into the implant heads and retained by friction.

Once the prosthetic bar was installed, the patient's pre-existing prosthesis was adapted and the retention clip was fixed, for this, the lower part of the prosthesis corresponding to the bar had to be spaced and the prosthetic retention clip was fixed on it. Then, with a perforated rubber, the entire bar was covered until the gum, leaving the fins of the brooch to come out through the perforation and exposing the entire area of the brooch that was desired to be fixed to the prosthesis. Finally, acrylic was added to the prosthesis in the spaced area and placed on the rubber so that the fins of the clasp were retained in the prosthesis. In addition to prosthetic retention, the bar simultaneously improved the biomechanics of the system and allowed clinical behavior equal to or greater than conventional implants. This procedure was validated in a randomized controlled clinical trial during 5 years of evaluation. In this study, 90 implants were inserted in 45 total toothless patients. Each patient received two implants in the anterior jaw, in a procedure without incisions and fully guided to reduce all surgical risk in older adults of public health systems. Immediately after insertion, the bars were connected to retain the prostheses in half of the patients. The other half was left with an O-Ring retention system. The degree of success in the bar system reached 97.7%, even greater than conventional implant systems that have documented a success of 90-95% at 5 years. The procedure lasted approximately 2 hours.

Claims

1. - A prosthetic retention system for toothless patients CHARACTERIZED because it comprises a prefabricated bar (1) and two implants (5); wherein said bar (1) is composed of a tubular centerpiece (2) with round cross-section or similar to an ovoid between 1 and 2 m in diameter and two hollow capsules (3) at its ends, which have a conical shape slightly larger than the head (7) of the implants (5); and where the implants (5) are formed by a single piece, which is composed of an upper area (12) that allows the connection with the bar and a lower area (13) corresponding to the section that is inserted into the bone of the patient.

2. - A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED because the capsule (s) (3) of the bar

(1) they are located at a distance of 10-25 mm between their centers, preferably 1 1 mm and have a groove (4) in one or both capsules.

3. - A prosthetic retention system for toothless patients according to claim 1 and 2 CHARACTERIZED because the grooves (4) occupy part or all of a wall of the bar (1) leaving partially or totally open one or both sides.

4. - A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED because the rod (1) is preferably made of a titanium alloy or surgical steel.

5. - A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED because the upper area (6) of the implant (5) is formed by 2 hexagonal pieces joined by a convex central part (8) and by a base provided with a bevel (10); where the upper hexagonal piece corresponds to the head of the implant (7) and has rounded angles in its contour; and where the lower hexagonal piece has flat faces (9) that coincide with those of the implant head.

6. - A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED because the upper end (6) of the implants (5) must be inserted under pressure in the bar (1).

7. A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED because the head (7) of the implant (1) allows to fix the capsule (3) of the bar (1) and where the convex area that connects The hexagonal parts are used to retain an O-Ring when the implant is used individually.

8. A prosthetic retention system for toothless patients according to claim 1 CHARACTERIZED to operate the system, a guide clamp must be used for the insertion of parallel implants, at the same height and centered on the bone.