The present invention refers to a method for the making of endocanalar bores in odontoiatric implementations and to the relevant system for the making of bores for endocanalar posts.
It is already known to the art that the glass fiber it is the most implemented material in the odontoiatric field for the re-construction of dental stumps, after being damaged by cavities or shocks. In theses cases, it is preferred the use of glass fiber alternatively to different dental alloys, since the former has a rigidity and bending modules such that to prevent braking of the root when stressed during the masticatory action. Further, the fiber is a inert and non toxic material, with respect to the alloys which are subjected to galvanic phenomena when contacting with other materials.
On the other hand, in commerce there are different kinds of posts made in glass fiber, and they are identified within two main groups, the first group comprises posts having a cylindrical shape with constant diameter, and the second group comprises posts having a non constant diameter (i.e., a varying diameter). Both groups provide that a portion of the post is designed to be inserted inside the root of the tooth to be treated, whilst the remaining portion is designed to be projecting out from the tooth for supporting the per prosthesis.
The cylindrical portion projecting out from the root and supporting the prosthesis is that having greater diameter (sometimes it has 5 times the inner portion diameter).
Therefore, it is easy to understand that a precise and correct protocol for the inserting and joining of the post to the outer base of the root (i.e., the base of the greater diameter portion following the smaller diameter portion inserted inside of the root) has to be followed, otherwise there may be a breaking of the post during masticatory action, as well as a possible detachment due to food infiltration between both surfaces. More precisely, a drawback of such technique for the implanting of a glass fiber post in a root is due to the procedure which is followed up to now:
On the other hand, as it is well known in the art all polymeric resins after polymerisation thereof, the same show a determined shrink degree, therefore it is easily understood that a complete and safe adhesion between post and tooth at the mating surfaces of the root it is hard to obtain.
Further, polymerised composite materials in dental applications never show same mechanical properties of a polymerised glass fiber such that in industrial applications at 200° C.
On the other hand, all dental roots show a taper ratio with a greater diameter in the direction facing upside the base of the root. Basically, this diameter it is almost ⅕ times the diameter of the stump. If the multidirectional masticatory stresses are not equally and even distributed at the point where the post changes diameter, i.e. greater cylinder becomes smaller cylinder, a breakage of the post itself may occur.
Therefore, the method and the system of the state of the art as above described has the following drawbacks:
Aim of the present invention is to provide method for the making of endocanalar posts which solves the above described drawbacks of the state of the art, wherein the following steps are provided:
Another aim of the present invention is to provide a system having a plurality of tools for the making of a endocanalar duct in a dental root and for the fixing of an endocanalar post within said duct, the system comprising:
Therefore, the present invention provides a method and a system according to the annexed claims.
A detailed description of a preferred embodiment of the method and the system for the making of bores or ducts for endocanalar odontoiatric posts according to the present invention will be given hereinafter, as a non limiting example and with reference to the annexed drawings, wherein:
With reference now to
Further and with reference to
With reference now to
With reference now figures from 4 to 6, a detailed description of the components of the system of the present invention will be given, and for the preparation of the root (milling operation).
With reference to
As it is shown in
The overall shape of the mill 1 determines inside the root 3 a series of mating surfaces for the post. It is here necessary to draw the attention to the fact that said mating surfaces inside the root 3 will determine a series of surfaces for the distribution of the masticatory stresses along the root axis, obtaining an improved strengthening of the whole assembly of the post-root, and an improved coupling between post and root is achieved with a perfect parallelism and concentricity.
With reference now to
With reference now to
More precisely, the mill 1 can be used only after the typical milling operation by means of said mill 100 (
Further and with reference to
With reference now to
According to the invention, for the measuring of the precise length of the endocanalar bore 2 within said dental root 3, it is provided a gauge 4 made of an extremely hard material, such as inox steel or similar. The gauge 4 has a first cylindrical body 40 elongated shaped and having an end surface 41 which is formed in a shape which is complementary to endocanalar bore 2 realised inside said tooth 3.
Further, on the body 40 it is mounted in a sliding manner is a second cylindrical body 42, said body 42 having a mating end thereof for cooperating with said tooth 3 and being shaped in a complementary shape to said second cup shaped milling portion 12 of said mill 1, therefore being also complementary to the shape of the relevant upper surface of said dental root 3.
The body 40 has a series of parallel and equally spaced grooves 43 each of them representing a predetermined metric distance (for example, 1/10 millimetres, or similar).
With reference now to
In this condition, the end part 41 abuts up to the maximum length of the endocanalar bore 2 allowing the opposite portion of the body 40 to expose one or more grooves 43 out from the body 42, the number of grooves exposed corresponding to the length/depth of the endocanalar bore 2 metered.
At this stage, the user can easily read and note the value of the length of the endocanalar bore so metered from the number of grooves 43 exposed.
With reference now to
More precisely, according to the method is provided a metering and supporting member 5 for an endocanalar post 6. The metering member 5 has a metering surface 50 where a series of grooves 51 are obtained, said grooves 51 being equally spaced and corresponding to the same metering of said series of grooves 43 onto said body 40 of said gauge 4.
To the skilled men of the art it will be apparent that according to the present invention, advantageously providing said grooves 51 onto said member 5 it is possible to readily convert the reading of the exact measured length of the endocanalar bore 2 onto the post 6, by simply arranging the post 6 inside said member 5 and marking the former with the corresponding groove 51, i.e. the groove 51 corresponding to the exposed groove 43 onto said body 40 of the gauge 4 during the metering of the length of said endocanalar bore 2.
In this manner, after signalling of the exact length onto said post 6, the latter is extracted out form said body 5 and cut at the corresponding marking, obtaining an endocanalar post 6 having an exact and complementary length to endocanalar bore 2.
According to another advantageous aspect of the present invention, the gauge 4 when inserted inside the relevant endocanalar bore 2 of the dental root 3, the same will provide to the skilled man a metering member for the radiographic inspection for the coupling post-root.
Number | Date | Country | Kind |
---|---|---|---|
PA2006A000041 | Sep 2006 | IT | national |
PA2007A000030 | Sep 2007 | IT | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/IB2007/002716 | 9/19/2007 | WO | 00 | 2/4/2010 |