MXPA99005343A - Dental implant - Google Patents

Abstract

The dental implant has an upper end having a cylindrical straight shape and terminated by a hexagonal protruding portion, both being perforated axially in alignment with the threaded pin. The perforation does not go beyond the lower extremity of the cylindrical portion and the threaded pin may be obtained with a diameter substantially smaller than a conventional diameter. The apical extremity of the pin is conical and is topped by a small tapering. The cortical zone of the bone is thus easily reached while ensuring the immobilization of the bone as well as a better grinding and crushing of the bone.

Description

The invention relates to a dental implant of the type used by surgeon dentists for insertion into the maxillary bone of the jaws of patients, so that they serve as a firm base for mounting the artificial teeth thereon.

The general technique of these implants was suggested more than twenty years ago by the Swedish professed Dr. Brape-mar and on it a large number of va-riaptes are known, aimed at improving or trying to improve the characteristics thereof in order to increase their efficiency.

In general terms, a dental implant is a unit that lodges in the bone of the jaw of the patient, fixing it appropriately to the same, until reaching the upper or coronal zone. In this area, the implant is dated in half to allow the stable fixation of an artificial tooth.

In order to carry out the perforation of the bone, at least one milling of the same is performed first to obtain a cylindrical interior hollow with a smooth surface, which is subsequently threaded with another tool, for example a tap, in order to obtain a threaded ipter-iary gap in which the implant can be adequately secured.

This last operation of threading of the smooth perforation of the bone is usually carried out by means of the own implants called autorascaptes, known for many years, which base their technique on the aforementioned of the males to be scratched.

For the US patent. A, 2.388.482, a surgical brace is known to perform perforations in the bones of the patients, which is endowed with a threaded area, topped by a portion dated from four longitudinal recesses, and the latter finished in turn by its characteristic apical end.

Thus, the US publication is also known. A. 2.472.103 the existence of a tool to carry out the threading, which has a cylindrical portion provided with helical thread which is topped, another conical end portion in which the said thread continues to extend, this provided Last conical zone of grooves to longitudinal recesses that favor the introduction of the tool.

It is also known by US. TO . No. 2,609,604, a conical implant provided with a helical thread provided with a plurality of longitudinal grooves which extend radially at its outer periphery.

For the US A 3,435,526, an implant is known that has a polygonal head, for example hexagonal section, for the action of it during its fixation to the bone, followed by another smooth cylindrical portion, which gives way to another cylindrical portion of smaller diameter which is threaded and provided with transverse through holes. The end of this implant is tropicapic, and longitudinal grooves circulate from said end.

For the US No. 3,672,058 is also known an implant whose body is conical and is occupied by a large pitch helical thread, which is also provided with longitudinal grooves. This implant is self-tapping, and its inner to apical end is conical with an angle of approximately 10 degrees in order to facilitate its introduction.

The teeth or fillets of thread present, from their extreme apical conical, a progressive increase both in their radii of head and in their radii of fund, since the base of the body is conical in its totality.

For the FR.A patent No. 2,395,738 is also known as a conical implant provided with helical teeth and grooves, both straight and inclined longitudinal.

In the US A. 4.324.550, desoribe a conical implant equipped with teeth or threads, which also give longitudinal grooves, which in turn have cutting bardes that facilitate the threading of the implant in the bone.

It is also known by the German publication - Rund um die werkzeugmaschipe - published in Spain with copyright of 1957 - Editorial Reverte, S. A .. taps with a cylindrical body topped by a tropicaconical portion, both with teeth or helical thread and with longitudinal grooves that provide cutting fronts.

The US A. 4,406,623 presents an implant that is conical and is provided with helical teeth extending throughout the entire body, up to an apical end that can end in a cone of approximately 90 degrees. Slots in helical direction interrupt the teeth and provide sharp edges that facilitate the introduction of the implant, which is self-invasive.

Some of these cited implants have in their head a hole drilled blind in the axial direction, in which a screw is screwed that later incorporates the artificial tooth. This hole extends from the polygonal end, crossing the height of the enclosed smooth cylindrical portion to travel a considerable length of the threaded area of the implant, so that the diameter of this threaded area is required in order to maintain adequate resistance This is a considerable disadvantage in many cases, since the location of the implant in narrow ridges of the patient's bone is very difficult, precisely due to the diameter of the portion provided with a tooth or thread.

On the other hand, it is well known by the dental technique that an implant obtains a better anchorage in the bone of the patient when it reaches the cortical bone, so that there is a tendency to favor that the implants are screwed into said cortical bone which is of copiderable measure greater hardness than the portion_of the medullary bone.

Also, there is the problem of the dental nerve in the posterior area of the jaw, in which it is essential not to incide with the implant in order to avoid the very serious inconveniences that it entails.

In this regard, - normally the insertion operations of the implant, as referred to above, are initiated. with the milling of the bone to provide a smooth cylindrical hollow prior to the introduction of the self-threatening implant as a tap.

In the operations of milling, the specialists deepen until reaching the shortest possible distance with respect to the dental nerve. In these operations, the milling cutters are housed at a high number of revolutions, so that once the hole is completed, the treatment begins with the self-tapping implant, which works at a very slow radial speed.

This usual practice is undesirable since there would be fewer risks involved in the treatment, that is, milling the hole to a greater distance from the dental nerve since with the increased workability, less control and inaccuracies in the treatment are generated.

Thus, the final operation with the self-grasping implant at reduced radial velocity would allow perfect control of its penetration up to the vicinity of the dental nerve, all with lower risks for the patient.

On the other hand, all these implants have the general characteristic that when performing the internal threading of the previously milled perforation, cuts are produced in sheets in the bone, laminar cuts that do not favor the subsequent formation of bone mass that agglutinates the bone. implant.

The invention has as objectives, a dental implant that allows to reduce the diameter of its autarascapte portion in the patient's hollow, facilitating its entry into the upper edge thereof when extremely narrow crests occur.

Another object of the invention is a dental implant that allows to bicarticalize the same achieving a greater anchorage in the cortical bone.

Another object of the invention is a dental implant that facilitates both the entry and the formation of the threading in the bone, the patient being able to access to the vicinity of the dental nerve with less risk when inverting the way of working the perforation.

Another object of the invention is a dental implant that relieves the friction produced during threading while promoting the grinding and grinding of the bone for better integration of the implant.

Another object of the invention is a dental implant that allows a more centered placement of the implant in the hole previously milled.

For the implementation of these objectives, the implant of the invention starts from a unit that is equipped with the following elements already known by the technique: - A generally cylindrical head whose outer face is occupied by a hexagonal projection, for example inscribed in a theoretical external diameter that is smaller than the diameter of the cross section of said cylindrical head.

- An axial blind perforation from the end of said outer face for the reception of a rear supporting screw of the artificial tooth.

- A cylindrical rod dated from teeth or helical thread, cut by a trapcacdnico end in which the toothing or scratching is extended along its entire lateral surface.

- Slots or longitudinal recesses, in variable number, extending from the apical free end of the implant, which are provided with at least one cutting edge.

On the basis of these particulars, the implant according to the invention is characterized in that the straight cylindrical portion of its head, from which the hexagonal projection departs, is of substantial generatrix greater than the dimension of the traditional ones, so that the frontal screened blind hole passing axially through the implant pa surpasses the extreme plane of said cylindrical portion.

. Thus, the threaded rod that arises from the cylindrical portion is integral in its cross section and may be smaller in its diameter. This reduction in diameter of the rod results in a greater ease of the implant for. act on narrow crests, all without loss or detriment of resistance. . _ From the studies carried out and from the experiences carried out, it has been noted that good practical results are achieved with the dental implant when the height or dimension of the straight generatrix of the cylindrical portion is between 0.7 and 5 millimeters, the total height of the threaded blind hole between 3 and 5 millimeters and the diameter of the rod between 2.5 and 6 millimeters.

Acting between these values and combining them properly the implant is perfectly prepared to face any type of crest of the patient's bone, without undergoing any variation in its correct direction and alignment and without impairing its resistance, as It was noted before.

The even neck, is wider and allows the housing of the screw that will retain the prosthesis without weakening said neck of the implant in the area of its narrowing, preventing the fracture thereof. Thus, the use of smaller diameter implants than conventional ones is also facilitated.

Likewise, the hexagonal projection is characterized in that it has a value of between 0.65 and 1 millimeter.

Also, the implant according to the invention also claims an apical end in a general cone shape, according to which the angle of this end is 120 degrees. This formation completes the extreme threading of the tropcocopic stem of the implant provided with longitudinal cutting grooves, allowing the milling of the bone perforation, which is performed at a high number of revolutions, is interrupted at a safe distance from the dental nerve, when works on the tooth in the posterior area of the jaw.

Particularly, the free end of this apical conical zone is flattened, so that it does not offer sharp edge in its penetration. The diameter of this chamfered section is between 15 and 25% of the diameter of the cross section of the implant, this being one of the characteristics claimed by the implant.

In the operation of threading with the implant of the invention, the chamfered tapering of the apical end allows closer to the dental nerve without greater risks since the speed of rotation during this threading is reduced and therefore perfectly subject to safety control by the specialist .

On the other hand, the conical carrot of the apical end favors the reach of the cortical zone of the bone - thus allowing the implant to settle in said area, of greater hardness, increasing the guarantees of immobility of the same.

Also, as the cutting implant at its apical end moves to a lesser extent towards the weakest cortical bone.

Coma is well known of the two cortical, in any cut of both jaws, the lingual or palatal is generally greater in its thickness and more ebúrneo than the vestibular, not being centered as planned ipicialmepte.

Therefore, the implant being au.taceptrapte, with active tip, allows to deepen more -in the pre-established bed. If necessary, it will be housed exactly in the space created by the milling cutter, since the implant in its apical zone has a shape similar to that of the milling cutter, not missing any length of the implant or leaving any empty hole in the bone.

The trancaptical zone of the autaroscapte implant provided with. thread and equipped with longitudinal grooves with cutting edges, usually four or six, shows a particular section, according to which and during the entry of the implant into the hole, previously milled, for the snore of the same, this is carried out with less friction, also favoring the grinding and crushing of the bone for its subsequent integration with the implant itself once introduced.

All this is materialized by means of the concrete geometry of the bottoms of the longitudinal grooves disposed between the projections provided externally of thread. Thus, from the cutting end located at a position furthest from the center of the implant, each cutting edge extends in a radial direction in a certain length to a point - in which it performs a curved-concave jog to the outside which it is related in continuity with another curved-convex portion towards, the exterior reaching the cutting end of the threaded projection, contiguous.

All these and other details of the invention will be appreciated in greater detail and concretion in the flat sheets that are bell-shaped, in which without any limiting character the following is represented: ...

- Figure 1 is an elevation of an implant according to the invention.

- Figure 23, represents a narrow ridge of a patient's bone.

- Figure 3-, is a sectional view of a bone showing the cortical area.

- Figure 4§, is a section of the posterior area of the jaw showing the dental nerve .. ^ "_ _ -, - - Figure 55 is a section of a perforation according to the invention, in the area close to the dental nerve .

- Figures 63 and 73, represent two views that show the different behaviors, normal and displaced, respectively, in relation to palatal or lingual and vestibular cortical.

- Figure 83 shows the behavior of the implant according to the invention in the previous milling carried out in the bone.

- Figure 93, represents the way of operating a conventional implant.- - Figure 103 shows a bottom view from the apical zone of an implant according to the invention.

- Figure 113 is a variant of the apical end of an implant according to the invention.

- Figure 123 is the top view of the implant of fig. 13 - Figure 13 - is a variant of the invention from its extreme apical.

- Figure 143 is the elevation of an apical end of the implant according to a variant of the invention, which corresponds to fig. 133 - Figure 153 is another variant of the apical end of the implant according to the invention.

According to fig. 13, we appreciate an implant (1) dated from a threaded portion (2), a head or neck (4) and a hexagonal shoulder (3) highlighted from the upper end (5) of said neck.

The portion (2) is provided with teeth or scraper (18 ') along its length, with the exception of its lower or apical end, in which the longitudinal recesses (19) provided with longitudinal cuts are noticed.

Also, the lower end of the implant is formed on the basis of trunco-acoustic narrowing (8, 9), the portion (9) having an angle of 120 degrees.

This portion (9) is in turn topped by a chamfer (9A) which has a circular section whose diameter is of the order of between 15 and 25% of the diameter of the threaded portion of the implant pin.

The head neck (4) has a dimension (A) in its generatrix, which, according to the invention, is between 0.7 and 5 millimeters.

The dimension (B) which is the sum of "the height of the generatrix of the head (4) and the height of the projection, d what is equal, the total depth of the threaded hole (6) is, according to the invention, between 4 and 6.5 millimeters.

In turn, the diameter of the threaded portion (18 ') of the stem or pin (18) of the implant, will be comprised between 2.5 and 6 millimeters, being lower than the conventional diameter represented pair the lines (7).

According to fig. 23, a usual narrow ridge (11) of a bone (12) is shown, which normally presents difficulties to be affected by a large diameter rod, so that it can be perfectly worked by the rod determined by the invention.

According to fig. 33, we show the preferred feature of the pre-milling (15) or bed of an imp.lapte in a tooth (12) made from its upper end (13), according to which the carpal bone (14) should be advantageously achieved by the implant in order to ensure its best anchorage.

According to figs. 43 and 53, we noticed a bone (12 ') corresponding to the posterior area of the jaw, through which the dental nerve runs (16). Being this nerve, which must necessarily be avoided, it will be appreciated how the previous milling (15) of the bone (12 *) can be interrupted at a distance (17) from it, which distance will provide the necessary safeguard to not affect said nerve After radiographic monitoring, the insertion of the implant could be continued at low revs, 15 to 20, for example, until it was close to the nerve path, if necessary.

According to figs. 63 and a, two performances are shown in which the lingual or palatal (14A) and vestibular (14B) cortical of a maxilla are shown. It is frequent that when performing the perforation of the bone and due to the greater hardness of the cortex. (14A), the different millings (15A, 15B, 15C) are displaced in the direction of the vestibular cortex (14B), even reaching, on occasion, to break this vestibular cortex.

The ideal penetration shown by fig. 63, represents how it has been performed in a centered and correct manner, in which the implant of the invention with its apical end also has a minimal tendency to move towards the weaker cortex, providing greater reliability to the location of said implant.

With reference to figs. 83 and 9i show the behavior of a traditional implant (21) (Fig. 93), which with its generally blunt or flat end (9B), leaves a bone space (15D) (9C, 15D) unused.

According to the invention, fig. 83, said space (9C, 15D) is fully worked by the end of the implant, the apical end thereof being adjusted perfectly to the shape of the said gap when presenting a shape similar to that of the drill.

From fig. 113, we deduce a practical solution for the apical end of the implant in its rod (2), in which we appreciate the longitudinal recesses (21) made at its end. This end is topped in a conical shape (23), of approximately 120 degrees, the end of which is in turn provided with the chamfered surface (9A) that eludes any living edge.

The said chamfered surface (9A) has a dimension between 15 and 25% of the dimension corresponding to the middle section of the rod (2) of the implant.

Fig. 103, shows the particular geometry of the apical end of the implant with the recesses (21) determined for the longitudinal recesses, in which the ends and cutting surfaces (25, 26) are also seen. The geometry of these recesses (21) is determined by «the curved-concave portions towards the outside (28), followed by the other curved-convex portions towards the exterior (27), which constitute the bottom of the said, emptied .

The solution proposed for this fig. 103, represents an end based on four hollows, corresponding technically to that of fig. 133, which shows the recesses (29) and the curved-concave (31) and curved-canvexa (30) portions, practiced in another solution with six recesses.

Fig. 143, represents the side view of the latter, which, technically, is corresponding to, that of fig. 113 In all of them, figs. 103, na, 133 and 14§} it is possible to appreciate the end chamfer (9A) of the end of the apical end of the implant according to the invention.

On the other hand, fig. 123, represents the hexagonal recess (3) of the implant, standing out from the upper base (5) of the cylindrical portion (4), as well as the position (24) that corresponds to the perforation (6) of fig. 13 Finally, from fig. 153, there is another practical solution for the implant at its apical end, with longitudinal recesses (33), conical end (34, 35) and chamfer (9A). In this case, the implant is equipped with perforations or holes (32), to be filled by the bone after its implantation.

On the other hand, it is indicated to the opportune effects, and as it is suggested or known by the US. No. 4,826,434, that the implant of the invention can be treated by surface etching, using techniques also known in other fields.

Concentrated acids are generally used, with the treatment of which the surface of the implant is increased very considerably.

It is worth highlighting, once the nature and advantages of this invention have been described, the non-limiting character of it, insofar as. the changes in the form, matter or dimensions of their. constituent parts will not alter their essentiality in any way, as long as they do not imply a substantial variation in the set.

Claims (1)

1. CLAIMS lg.- Dental implant that has an upper end in generally cylindrical form of straight generatrix from which a prismatic or protruding portion of preferably hexagonal section protrudes outward, this end being axially drilled with an internally threaded blind hole, with an external threaded rod epte terminated at its apical end by a truncated portion, also threaded, finished off at the same time by another cone-shaped end, also comprising longitudinal grooves that have sharp bardes and provide threaded sectors between them, characterized by, - the height of the hexagonal projection is between 0.65 and 1.5 millimeters, - the internally-threaded axial perforated hole has a length from its exterior that does not extend beyond the lowermost end of the upper straight cylindrical portion, this length being between 3 and 5 millimeters, - the height of the upper straight cylindrical portion has a dimension comprised between 0.7 and 5 millimeters, - the diameter of the threaded cylindrical rod that arises from the aforesaid cylindrical portion has a dimension comprised between 2.5 and 6 millimeters, - the conical end that terminates the threaded trunk portion of the rod has an angle of approximately 120 degrees and is topped by a flat chamfered surface of generally circular plan whose diameter is between 15 and 25% of the diameter of the rod. the threaded portion of the rod, - the longitudinal grooves have at the bottom of their cutting ends, portions that are rounded curved-concave outwards, from which other rounded curved-convex outwardly extending portions extending to the cutting edges of the adjacent sector are established . 23. - Dental implant, according to claim 13, characterized in that when the implant is of a diameter greater than 3 millimeters, the internal bore can go beyond the lowest plane of the straight cylindrical portion. Summary A dental implant with an upper end of a straight cylindrical shape finished off by a hexagonal projection, both being axially perforated in alignment with the threaded rod. The perforation does not exceed the lower end of the cylindrical portion and the threaded rod can be made with a diameter significantly smaller than conventional. The apical end of the rod is conical and is topped by a small chamfer. It favors the reach of the cortical zone of the bone, increasing the guarantees of immobility of the same, as well as making a better grinding and crushing of the bone.