ES2864877B2 - ENDODONTIC OBTURATOR WITH GUTTA-PERCHA ROD AND APPLICATION PROCEDURE - Google Patents

Description

DESCRIPTION

ENDODONTIC OBTURATOR WITH GUTTA-PERCHA SHAFT AND PROCEDURE

OF APPLICATION

OBJECT OF THE INVENTION

The present invention refers to an endodontic obturator with a gutta-percha stem through which it is intended to overcome the limitations of the existing ones, improving properties and characteristics, while providing the clinician with greater facilities to perform a quality and predictable endodontics. long term in the simplest way possible.

For this, one of the most representative innovations that the endodontic obturator of the invention presents is that the gutta-percha stem has different cones along its length, while the existing obturators present a continuous conicity.

Another additional innovation that the endodontic obturator of the invention presents is that the gutta-percha coating, intended to fill a root cavity, does not completely cover the stem up to the very apex, but rather leaves an end zone free of coating.

The invention also describes the application procedure.

The invention finds special application in the field of industry related to the manufacture of dental elements.

TECHNICAL PROBLEM TO SOLVE AND BACKGROUND OF THE INVENTION

Endodontics is a science integrated into the set of health sciences. Its objective is the study of the structure, morphology, physiology, pathology and healing techniques of the dental pulp and periradicular tissues. The advances experienced in this area in recent years highlight the need for permanent updating and the creation of new instruments that accompany the knowledge acquired and facilitate and improve clinical activity.

The realization and treatment of a dental root canal for the healing of a damaged dental pulp has three main objectives:

- remove the pulp tissue or its debris,

- shape and disinfect the walls of the duct, and

- seal three-dimensionally, as far as possible, the pulp cavity.

The obturation of the root canals constitutes the last phase of the treatment, although it should be given the same importance as the rest of the previous phases. When evaluating a treatment on radiographs, the only thing that can be judged is the quality of the filling performed, the quality of the root canal preparation being much more difficult to assess.

The obturation seeks to prevent the development of bacteria that may have remained inside the ducts, to prevent the passage of exudates from the periapex to the interior of the duct that may facilitate the development of these bacteria, and to prevent the passage of bacteria from the periodontium inside the canal. The correct performance of this phase consists of a normal extension and normal condensation throughout the entire root canal, from the entrance to the apical constriction. Passage of filling materials beyond the apical constriction damages the apical connective tissue stump that is the base of the repair. Underextension and undercondensation will leave empty spaces inside the canal where germs can proliferate and cause endodontic failure in the long or short term.

Gutta-percha is the main material used to fill root canals since its introduction by Bowman in 1867. It is a natural organic polymer (polyisoprene). The different stereochemical forms of gutta-percha give it different properties, even though its chemical composition is the same.

The purpose of softening or plasticizing the gutta-percha by means of heat is to improve its molding capacity in order to achieve a better adaptation to the irregularities of the internal anatomy of the tooth and thus achieve a more complete obliteration of the root canal system. The presentation of gutta-percha depends on the technique to be used, all of these techniques requiring the use of cement to seal the interface between the walls of the canal and the gutta-percha. Lateral condensation techniques and vertical condensation of hot gutta-percha are carried out with gutta-percha points, although these techniques are slow and difficult to execute, being already surpassed by other more current techniques.

In this way, in the state of the art there are many techniques for plasticizing gutta-percha with heat and thus making it more moldable. In some of them, small bars of gutta-percha are used, which are softened inside a specific dispensing gun. In others, the gutta-percha is placed in cannulas that are placed in a heater to soften the material, subsequently being introduced into the ducts with the help of a gun. There are techniques that use gutta-percha contained in syringes that plasticizes in heaters and is introduced into the ducts using files or compactors. Others use the gutta-percha that covers a compactor, so that the softening of the material is carried out in the canal itself when the instrument is rotated. Finally, there are other techniques that use a gutta-percha coating placed on a stem and plasticized in electric ovens.

Of all these techniques mentioned, the one that has a relatively simpler learning curve, is quicker and reaches the apical area more effectively is the one mentioned last, the one that refers to the use of plasticized gutta-percha that covers a stem.

Going deeper into this technique, at the beginning stems were used that were made of stainless steel, titanium or plastic and had a continuous taper of 2%. The materials with which this stem was made evolved. Stems currently have a continuous 4% taper and are made of more flexible plastics or gutta-percha interlocked by polymer chain junctions.

Plastic stems have the problem that they provide poor sealing quality, they tend to extrude material and, on many occasions, the stem is filled with the apical stem.

For its part, the fact that the stem is made with gutta-percha simplifies the performance of a retreatment or the placement of a post if necessary after the initial treatment.

However, despite the fact that extrusion affects all the stems, it is greater in the plastic ones than in the gutta-percha ones, so that they tend to extrude more filling material than necessary, especially in apical extrusion on straight canals, flowing the material beyond the working length in the canal, causing an accumulation of gutta-percha in the periapical area, where it can cause undesirable effects.

Thermoplastic gutta-percha techniques tend to extrude more filler material than lateral condensation. Specifically, systems with thermoplasticized gutta-percha covering a stem tend to extrude more compared to continuous wave condensation systems. It must be taken into account that plasticized gutta-percha follows Poiseuille's law of fluid dynamics, which determines that the flow is directly proportional to the fourth power of the radius of the duct through which it circulates and inversely proportional to the length of the duct and the viscosity. of the fluid, which is directly related to the working temperature.

Plastic stems are available in different gauges and with a constant 4% taper. They are 25mm long and the gutta-percha covers the stem from the apical area up to 15mm. These stems are introduced into the root canals with the plasticized gutta-percha to fill said canal and, once the gutta-percha has solidified, the stem is cut, remaining as part of the filling material. This process is carried out quickly and easily, but it has a number of drawbacks, such as the difficulty of placing posts or performing retreatments, as the stem remains rigid inside the canal. Although there are techniques to carry out the elimination of the stem in case of wrong positioning or any other need, the stems between calibers 25 and 50 are made of an insoluble plastic that presents an additional complication for its removal.

Due to the described drawbacks, modifications have arisen in the plastic stems. With the same dimensions defined above, gutta-percha stems have been made intertwined by joints of the polymer chains where the core is more resistant and the surface more fluid. However, these modifications only manage to avoid a part of the problems that have been mentioned.

The present invention describes an endodontic obturator formed by a stem with a variable conicity, not covered with gutta-percha up to the apex and whose composition includes a gutta-percha-based thermosetting crosslinked elastomer that, although it can burn or degrade if heated, does not melt. when brought to working temperature.

On the one hand, the variable conicity allows the apical area of the obturator to have a greater conicity than the rest of the stem, so that it can better adapt to the configuration of the root canal and, being free of gutta-percha at the apex of the obturator , blocks gutta-percha extrusion beyond this point.

On the other hand, it increases the pressure on the plastic gutta-percha that covers the stem, already located in the area of less conicity, favoring the filling of possible lateral canals.

Additionally, the composition of the stem creates a hermetic block with the gutta-percha coating that prevents the adhesion of the two gutta-percha and allows its fluidity.

DESCRIPTION OF THE INVENTION

In order to achieve the objectives and avoid the drawbacks mentioned above, the present invention describes an endodontic obturator with a gutta-percha stem for deposition in a root canal made in a tooth. The root canal has been made by a rotary instrument, with a certain taper and a diameter that increases progressively from the end, transferring these dimensions to the root canal.

The stem is made up of an apical area, an intermediate area and a stiffness area at the end of which a stop is located that separates the stem from the grip area of the obturator.

The stem incorporates a gutta-percha coating that is located in the intermediate zone, leaving the apical area free of gutta-percha coating.

Preferably, the intermediate zone is located 2mm from the apex of the stem.

A main characteristic of the stem is that it has a variable conicity formed by a first conicity in the apical area of the stem and a second conicity in the intermediate area of the stem, smaller than the first conicity.

The first taper may be greater or less than the root canal taper, focused on the fit of the stem apex to the root canal, but is preferably the same, so that the fit is most accurate.

Preferably, the first taper is 6%, equal to that of the rotary instrument in charge of shaping the root canal, while for the second taper it is preferred that it be 4%.

BRIEF DESCRIPTION OF THE FIGURES

To complete the description of the invention and in order to help a better understanding of its characteristics, according to a preferred embodiment of the same, a set of drawings is attached where, by way of illustration and not limitation, represented the following figures:

- Figure 1 represents a side view of the obturator where the stem has a gutta-percha coating in the intermediate area, leaving the apical area free. - Figure 2 represents a side view of the stem of the endodontic obturator of the invention, with an enlargement to show in more detail the difference in conicities between the apical zone and the intermediate zone.

- Figure 3 represents a sectional view of a dental piece in which a coronal opening and a root canal have been made.

- Figure 4 represents the dental piece of figure 3 with an obturator beginning the introduction into the root canal.

A list of the references used in the figures is provided below:

1. Gutta-percha stem.

2. Gutta-percha coating.

3. Root canal.

4. Coronal area.

5. End of root canal.

6. Stop.

7. Bone area.

a. First taper.

b. Second taper.

the. apical area.

lb. intermediate zone

lc. stiffness zone

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

Figures 1 and 2 represent an embodiment of the shutter of the invention.

Figure 1 represents the obturator of the invention, formed by a gutta-percha stem (1) with a gutta-percha coating (2), a stop (6) and a grip zone.

Figure 2 represents the gutta-percha stem (1) of the obturator of the invention, without the gutta-percha coating (2), in order to more clearly appreciate the difference in conicity along the stem (1).

In both figures it can be seen that the gutta-percha stem (1) has a length divided into three zones: an apical zone (1a), an intermediate zone (1b) and a rigid zone (1c) before reaching the top (6). ), located at the end opposite the apex of the obturator and separating the grip area.

In the chosen embodiment, the gutta-percha stem (1) is 25mm long and has a gutta-percha coating (2) starting 2mm from the apex. This means that the gutta-percha of the coating (2) that is plasticized starts from a more coronal area than in the existing obturators, where the gutta-percha reaches the very apex, completely covering it. In this way, a reduction in the risk of overextrusion is achieved, as will be described later.

The gutta-percha stem (1) of the obturator of the present invention has different conicities (a, b) along its length, while the existing ones have a uniform conicity.

The dimensions of the obturator are designed so that the flexibility of the obturator decreases in the portion of the gutta-percha stem (1) farthest from the apex, in the rigidity zone (1c), where the diameter is 1.10 mm, with the objective to facilitate its handling.

It is important to insert the obturator creating direct access to the root canal (3), avoiding bending in the coronal third of the gutta-percha stem (1), that is, in the area of rigidity (1c).

The invention will now be further described by way of example with reference to the accompanying figures:

Figure 1 represents the obturator where the gutta-percha stem (1) has a plastic gutta-percha coating (2) between 2mm and 16mm from the apex, in the intermediate area (1b) of the stem (1). The gutta-percha coating (2) increases the diameter of the stem (1) at 2mm from the apex to 0.45mm and at 16mm to 1.30mm. From 16mm, the stem (1) has a diameter of 1.10mm up to the length of the obturator.

Figure 2 represents a view of the gutta-percha stem (1) of the obturator of the invention in a preferred embodiment with the measurements that characterize it. It is a gutta-percha stem (1) with an apical diameter of 0.25 mm and a first conicity (a) of 6% in the apical zone (1a), that is, from apical to 2mm. Subsequently, the stem (1) continues with a second taper (b) of 4% along the intermediate zone (1b), up to 16mm from apical. Therefore, the stem (1) has a diameter of 0.37mm at 2mm and 0.93mm at 16mm. In this view it can be seen that the first conicity (a) and the second conicity (b) are presented in continuity.

It must be considered that the considered obturator has a gutta-percha stem (1) of caliber 25, although there is a whole range of stems (1) of calibers that usually range from 25 to 55 and can even be smaller than 25 and larger than 55. .

The technique for using this type of shutter is quick and simple. Figure 3 represents a dental piece where, starting from a coronal area (4), a root canal (3) has been instrumented with rotary systems and the appropriate pre-filling irrigation has been carried out. Next, with a tester of the same dimensions as the stem of the gutta-percha (1) of the obturator, the apical caliber is determined and a radiograph is taken to confirm that the stem (1) adapts perfectly to the apical constriction established by the conometry technique. Subsequently, the sealing cement is introduced with a paper point that is inserted up to the middle third of the total length of the canal (3), it is spread and the excesses are removed with two more paper points, the first up to a distance of 1mm from the end of the duct (5) and the second to the end of the duct (5).

The obturator, with the gutta-percha coating (2), is plasticized in a specific oven until reaching the determined working temperature. Subsequently, the obturator is introduced into the root canal (3) with the rubber stop (6) that incorporates the obturator adjusted to the length of the canal (3) until the apical constriction is reached. Once the plasticized gutta-percha is deposited in the duct (3), the stem (1) is cut with sharp blades or burs and a vertical condensation is performed, the stem (1) remaining cut as part of the sealing material.

Existing rotary instruments have a 6% taper. In this way, the stem (1) of a traditional obturator, whose taper is 4%, means that, once the obturator is completely covered, up to the apex, with plasticized gutta-percha, it is introduced into the root canal (3), the difference of conicities creates a hole through which the plasticized gutta-percha will extrude uncontrollably to the end of the canal (5). This presents a problem, since the root canals (3) are located in the bony area (7) of the jaws, which implies that part of the plasticized gutta-percha can be extruded into the bony area (7), creating problems. futures.

By means of the present invention, by using a gutta-percha stem (1) with an apical zone (1a) of 2mm in length, which is not covered with gutta-percha and which has a first conicity (a) of 6%, equal to that of the canal (3), the very apex of the stem (1) blocks the end of the root canal (5), so that the plasticized gutta-percha will run along the free gap between the surface of the root canal cavity (3), with a taper of 6%, and the intermediate zone (1b) of the stem (1), with a taper of 4%. As the amount of fluid gutta-percha is less, there is a decrease in shrinkage, so the possibility of shrinkage of the material decreases. In addition, by generating a greater force between the gutta-percha stem and the canal walls, due to the greater degree of friction, a greater flow is achieved.

The procedure for applying the endodontic obturator of the invention, once a root canal (3) of dimensions determined by a rotary instrument of determined conicity has been made, a verifier has been introduced to determine the caliber of the gutta-percha stem (1) of the obturator to be used in a certain position, with the gutta-percha coating (2) located in the intermediate zone (1b) of the stem (1) and the obturator having been heated to bring the gutta-percha of the coating (2) to a state of plasticity, comprises the following phases:

a) Insert the stem (1) into the root canal (3) until the apex stops, blocking the root canal (3) in the position determined by the passage of plasticized gutta-percha;

b) Let the plasticized gutta-percha flow for the three-dimensional obturation of the root canal (3);

c) Wait for the gutta-percha to solidify;

d) Cut the stem through the coronal area (4) of the tooth.

In any event, the present invention should not be limited to the embodiment described herein. Other configurations can be made by those skilled in the art in view of the present description. Accordingly, the scope of the invention is defined by the following claims.

Claims (3)

1. - Endodontic obturator with a gutta-percha stem (1) comprising an apical zone (1a), an intermediate zone (1b) and a rigidity zone (1c), and with a gutta-percha coating (2) for deposition in a canal root canal (3) of a certain conicity, the obturator being characterized by: - the gutta-percha coating (2) is located in the intermediate zone (1b) of the stem (1), leaving the apical zone (1a) free of the gutta-percha coating (2), and - the stem (1) has a variable taper formed by: - a first conicity (a) in the apical zone (1a), and - a second conicity (b) in an intermediate area (1b), with a smaller angle than the first conicity (a), where: - the tapers (a, b) of the stem are continuous. 2. - Endodontic obturator with gutta-percha stem (1), according to claim 1, characterized in that the first taper (a) is 6% and the second taper (b) is 4%. 3. Endodontic obturator with a gutta-percha stem (1), according to claim 1 or 2, characterized in that the intermediate zone (1b) is located 2mm from the apex of the stem (1).