Passive position fixture for multi-implant restoration and impression taking method for multi-implant restoration

Abstract

The present invention provides a passive position fixture for multi-implant restoration and a method for taking a mold for multi-implant restoration: multiple implants are fixed on the gum bone, a columnar restoration base is installed on each implant, and the inner and outer walls of the upper section of the restoration base are both irregular surfaces; the passive position fixture is cut into sections outside the mouth by printing resin material as a whole with CAD-CAM, and then reconnected in the mouth with self-curing resin, each printed material cutting block is provided with a slot, the inner wall contour of the slot matches the outer contour of the upper section of the corresponding restoration base, and an insert is provided in the slot to embed the central through hole of the restoration base; the upper section of the restoration base is respectively inserted into each slot of the passive position fixture and kept relatively fixed laterally. Compared with the prior art, the passive position fixture made based on the solution provided by the present invention has a higher degree of coordination with the restoration base, and is more convenient to install in the patient's mouth, which is more patient-friendly.

Description

Technical Field

[0001] The invention relates to the technical field of implant restoration, and in particular to a passive position fixture for multi-implant restoration and a molding method for the multi-implant restoration. Background Art

[0002] As people's requirements for oral health are increasing, there are more and more cases of multiple consecutive tooth loss and edentulous jaws requiring implant restoration. In the restoration of multiple implants, how to accurately replicate the three-dimensional position of the implant through impression is the key to achieving passive positioning and an important factor in ensuring the restoration effect. [1] .

[0003] At present, the most widely accepted clinical method is to obtain the accurate position of the implant by passively placing the implant transfer rod. Studies have found that open window impressions are more accurate than closed window impressions. [2] When taking impressions of multiple implants, the impression bar can be connected and fixed by cutting and reconnecting the dental floss resin or resin rod to obtain a more accurate impression. [3] . However, the commonly used method of using an open transfer rod and connecting it with resin to obtain a passive position has the problem of requiring a high degree of mouth opening for the patient, and connecting the transfer rod in the mouth with dental floss and self-curing resin has a strong odor, takes a long time, and the patient's experience of the consultation is poor. At present, the compatibility of the metal passive fixture printed by SLM (Selective laser melting) improved by the technical room with the implant base needs to be improved. In the process of clinical use, it is often found that its accuracy cannot meet the requirements.

[0004] In summary, the preparation of passive implant models is a key step in multi-unit implant restoration. Various existing technologies have defects to varying degrees. Among the methods of implant restoration, it is generally recognized that open window impressions are more accurate than closed window impressions. In the open window impression method, the more traditional approach is to use an open transfer rod and wrap the transfer rod with dental floss in an 8-shaped pattern, and then apply self-curing resin on the dental floss to connect and obtain the passive position. The main problem of this method is that it has high requirements for the patient's mouth opening, and the clinical operation has a strong odor and takes a long time, which makes the patient feel poor when visiting the doctor; or after making the initial impression, the transfer rod is connected on the model, and then the passive position transfer rod is disconnected and reconnected before clinical impression. This approach can save time for clinical operation, but it cannot solve the problem that the open window impression method is difficult when the patient's mouth opening is limited.

[0005] At present, there is an improved closed-mouth impression method for obtaining the passive position of implants. After the initial impression of the implant position is made clinically with a closed-mouth transfer rod, a suitable restoration abutment is selected in the technical room. Then, according to the appearance of the trimmed restoration abutment, SLM is used to print the metal inner crown and connecting rod as a passive fixture. When the abutment is tried on clinically, the SLM metal fixture is installed and connected with self-curing resin to take a closed-mouth passive position impression. This improved passive fixture realizes the method of closed-mouth impression to obtain the passive position, and solves the problem of being unable to open a window impression when making a multi-unit implant passive position model when the patient's mouth opening is not enough. However, the compatibility of the SLM metal fixture and the implant abutment needs to be improved. During clinical use, it was found that its accuracy could not meet the requirements. Summary of the invention

[0006] The present invention improves the matching degree between the passive position mold-taking fixture and the implant base by digitally designing a resin fixture printed by CAD / CAM according to the different structures inside the permanent base of different implant systems, thereby completing the passive position mold-taking of the implant in a closed-mouth impression manner, which is more conducive to the convenience of clinical operation and the comfort of the patient. In order to achieve this purpose, the present invention provides a passive position fixture for multi-implant restoration, and a method for multi-implant restoration using the passive position fixture prepared based on digital design, and the specific scheme is as follows:

[0007] A passive position fixture used for multi-implant restoration, wherein multiple implants are fixed on the gum bone, and a columnar restoration base is installed on each implant, wherein the restoration base is provided with an axial through hole, and the inner wall and the outer wall of the upper section of the restoration base exposed to the soft tissue are both irregular surfaces;

[0008] The passive position fixture is composed of a prefabricated block of overall 3D printing, which is cut into sections outside the mouth and then reconnected inside the mouth with an adhesive, each of which is provided with a slot, the inner wall contour of the slot matches the outer wall contour of the corresponding repair base, and an insert embedded in the through hole is provided in the slot, and the overall or partial outer contour of the insert matches the inner wall contour of the through hole;

[0009] The upper section of the repair base is respectively inserted into the respective slots of the passive position fixture, the inner walls of the slots are fitted with the outer walls of the upper section of the repair base, and the insert is embedded in the through hole and fits with the inner wall of the through hole to ensure that the passive position fixture installed on the repair base remains relatively fixed laterally.

[0010] Furthermore, a notch is provided on the upper side wall of the repair base, and the insert is embedded downwardly into the notch;

[0011] The local width of the insert embedded in the notch is equivalent to the width of the notch.

[0012] Furthermore, the binder is a self-curing resin.

[0013] Furthermore, each of the repair abutments is fixed on a plaster model that is consistent with the position information of the intraoral implant, and a prefabricated block of resin material is integrally printed using CAD-CAM based on the 3D optical scanning position information of the repair abutment on the plaster model.

[0014] Furthermore, the repair base is detachably mounted on the implant.

[0015] Furthermore, the lower end of the repair base is inserted on the implant, a screw threadedly connected to the implant is provided in the through hole, and the inner wall of the through hole is provided with a step for clamping the screw head.

[0016] A method for taking an impression of a multi-implant restoration based on the passive position fixture comprises the following steps:

[0017] S1. Use a transfer rod to make a preliminary impression of the position of multiple implants, and then make a plaster model containing multiple implant substitutes after reproducing the model;

[0018] S2, selecting the repair abutment 20 according to the plaster model of multiple implants, and fixing each repair abutment on the implant substitute in the plaster model;

[0019] S3. Perform preliminary grinding on the restoration abutment and find a common positioning path for multiple units;

[0020] S4, performing 3D optical scanning on the restoration abutments to obtain digital information and three-dimensional positional relationship of each restoration abutment;

[0021] S5, according to the digital information and the three-dimensional position relationship of each restoration base, using CAD-CAM to print out a whole prefabricated block, the prefabricated block is provided with a plurality of the slots;

[0022] S6, installing the whole prefabricated block onto the repair base on the plaster model, and inserting each repair base into a corresponding slot, cutting the prefabricated block into a plurality of cutting blocks, wherein each cutting block is provided with a slot;

[0023] S7, removing each restoration abutment on the plaster model and installing it on the implant in the mouth, inserting each cutting block into each restoration abutment in the mouth respectively, and bonding multiple cutting blocks together in the mouth to form the passive position fixture.

[0024] The advantages of the present invention are:

[0025] (1) In the method of preparing the passive position of implantation by closed-mouth impression, the present invention adopts digital technology to achieve the problem that the passive position fixture needs to improve the compatibility with the implant base, and the passive position fixture in the mouth is cut after printing a whole piece and then bonded in the mouth. The passive position fixture made in this way has a better multi-unit common positioning path, better accuracy, and can be better adapted to the restoration base in the mouth, without the need for multiple reworks in the patient's mouth.

[0026] (2) The present invention improves the matching degree between the passive position mold taking fixture (i.e., passive position fixture) and the implant abutment (i.e., repair abutment) by digitally designing a resin fixture printed by CAD / CAM according to the different internal structures of the permanent abutments of implants of different systems, thereby realizing the passive position mold taking of the implant in a closed-mouth impression manner.

[0027] (3) The present invention is designed to add a hollow retaining device to the passive clamp body, which can strengthen the bonding between the passive clamp and the silicone rubber impression material and reduce the possibility of deformation of the impression material during the demolding process.

[0028] (4) The present invention is designed to take a mold based on the abutment level, which can help inject the bite record silicone rubber on the selected permanent abutment while trying the passive position clinically, thereby improving the accuracy of the jaw relationship record. After the clinician determines that the passive clamp is in place, the range of clinical connection is smaller, which is more conducive to the convenience of clinical operation and the comfort of the patient. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0030] Figure 1 A schematic diagram showing the outlines of a plurality of restoration abutments and a notch provided at the upper end;

[0031] Figure 2 The figure shows a stereoscopic view of a single restoration abutment, the bottom of which is provided with an insert for inserting on the implant;

[0032] Figure 3 A cross-sectional view of a screw within a restoration abutment for fastening the restoration abutment to an implant is shown;

[0033] Figure 4-5 Shows a perspective view and a bottom view of the dynamic clamp;

[0034] Figure 6A schematic diagram showing the installation of a printed 3D printed prefabricated block used as a subsequent passive position fixture body on a restoration base on a plaster model;

[0035] Figure 7 For the general Figure 6 Schematic diagram of cutting a 3D printed prefabricated block into multiple pieces;

[0036] Figure 8 A schematic diagram showing the installation of a restoration abutment onto an intraoral implant and the preparation of installing a plurality of cutting blocks onto each restoration abutment;

[0037] Fig. 9 Shows Figure 8 Schematic diagram of multiple printed material cutting blocks being installed on each restoration abutment in the mouth;

[0038] Fig.10 A schematic diagram showing how to bond multiple cut blocks of printing material together in the mouth using self-curing resin to ultimately form a passive position fixture;

[0039] Fig.11 Cross-sectional view of the passive fixture installed intraorally on a multi-implant restoration abutment.

[0040] Description of reference numerals:

[0041] 10- gum soft tissue; 20- restorative base; 21- notch of the restorative base; 22- lower end plug of the restorative base; 23- lower end boss of the restorative base; 30- passive position fixture; 31- slot; 32- embedded block; 33- cutting block; 34- self-curing resin; 35- 3D printed prefabricated block; 36- mounting screw in the through hole of the restorative base; 40- plaster model. DETAILED DESCRIPTION

[0042] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0043] In order to fully understand the present invention, detailed steps and detailed structures will be proposed in the following description to illustrate the technical solution of the present invention. The preferred embodiments of the present invention are described in detail below, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0044] The present invention provides a passive position fixture for accurately locating the position of implant impressions during multi-implant restoration. Multiple implants (not shown in the figure) are fixed on the gum bone, and a columnar restoration base 20 is installed on each implant. The restoration base 20 is provided with an axial through hole. The inner wall and outer wall of the upper section of the restoration base 20 exposed to the soft tissue are both irregular surfaces, such as Figure 1 Continue reading Figure 4-5 The passive position fixture 30 is composed of a prefabricated block 35 of integral 3D printing, which is cut into sections outside the mouth and then reconnected inside the mouth with an adhesive (e.g. Fig.10 ), each cutting block is provided with a slot 31, the inner wall contour of the slot 31 matches the outer wall contour of the corresponding repair base 20, and an insert 32 that can be embedded downward into the through hole of the repair base 20 is provided in the slot 31, and the outer contour of the insert 32 matches the inner wall contour of the through hole. The upper section of the repair base 20 is respectively inserted into each slot 31 of the passive position fixture 30, the inner wall of the slot 31 fits with the outer wall of the upper section of the repair base 20, and the insert 32 is embedded in the central through hole of the repair base 20 and fits with the inner wall of the through hole, so as to ensure that the passive position fixture 30 mounted on the repair base 20 remains relatively fixed in the horizontal direction.

[0045] Among them, the inner and outer walls of the upper section of the repair base 20 are both irregular surfaces. In other words, the inner and outer walls of the upper section of the repair base 20 are uneven surfaces. For example, when the side wall of the repair base 20 is provided with a longitudinal rib, then the inner wall of the corresponding slot 31 of the passive position fixture 30 is provided with a vertical groove. When the passive position fixture 30 is inserted into the repair base 20, the two remain relatively fixed and cannot rotate laterally.

[0046] The passive position fixture 30 provided by the present invention for accurately locating the position of the implant impression during multi-implant restoration is prepared according to the 3D scanning model of the restoration base 20. The passive position fixture 30 is installed on the restoration base 20, and the inner and outer walls of the restoration base 20 are respectively fitted with the inner wall of the slot 31 and the outer wall of the insert 32, thereby achieving a tight snap fit between the restoration base 20 and the passive position fixture 30, thereby effectively avoiding the sliding displacement of the passive position fixture 30 relative to the restoration base 20, thereby improving the accuracy of the subsequent impression taking for multi-implant restoration based on the passive position fixture 30.

[0047] The entire side wall of the insert 32 fits with the inner wall of the central through hole of the repair base 20 , or the partial side wall of the insert 32 (at least including the opposite side walls) fits with the inner wall of the central through hole of the repair base 20 .

[0048] Preferably, a notch 21 is provided on the upper side wall of the repair base 20, and the notch is connected to the upper opening of the repair base 20. When the passive position fixture 30 is inserted on the repair base 20, the insert 32 is not only embedded in the central through hole of the repair base 20, but also just embedded in the notch 21, further limiting the relative fixation between the repair base 20 and the passive position fixture 30. The local width of the insert 32 embedded in the notch 21 is equivalent to the width of the notch.

[0049] In an optional embodiment, we use CAD-CAM to print the resin material prefabricated block 35 based on the 3D optical scanning position information of each restoration base, and then fix the 3D printed prefabricated block 35 on multiple restoration bases 20 on the plaster model 40 to cut into multiple cutting blocks 33. As a preferred option, we use self-curing resin to bond the cutting blocks 33 together in the mouth as the passive position fixture 30. It should be noted that self-curing resin is only a better adhesive. In specific applications, we can choose other types of adhesives, which will not be repeated here.

[0050] In an optional embodiment, the restoration base 20 is detachably mounted on the implant. Figure 2 As shown, the lower end of the repair base 20 is provided with a nearly annular boss 23, and below the boss 23 is an insert block 22. The repair base 20 is initially fixed to the implant by inserting the insert block 22 into the slot on the implant. A screw 36 connected to the implant thread is provided in the through hole, and the screw 36 is screwed downward into the internal thread hole of the implant to achieve docking and fixing of the repair base 20 and the implant. Among them, a step for clamping the screw head is provided on the inner wall of the through hole.

[0051] like Figure 6-11 As shown, the steps of the impression taking method for multi-implant restoration based on the passive position fixture 30 are further described below:

[0052] S1. Use a transfer rod to make a preliminary impression of the position of multiple implants. After the model is copied, a plaster model containing multiple implants is prepared. The three-dimensional position and shape of the implant substitute in the plaster model are consistent with the intraoral implant.

[0053] S2. Select a restoration base 20 according to the plaster model of multiple implants, and fix it on the implant substitute in the plaster model.

[0054] S3, preliminarily grinding the repair base 20 to find a common positioning path for multiple units. The inner wall and outer wall of the upper section of the repair base 20 exposed to the soft tissue are both irregular surfaces.

[0055] S4. Perform 3D optical scanning on the implant restoration base 20 to obtain the digital information and three-dimensional position relationship of each restoration base 20, that is, the coordinate information of the restoration base in the spatial coordinate system in the scanning software.

[0056] S5. According to the digital information and three-dimensional positional relationship of each repair base 20, a whole prefabricated block 35 is printed by 3D printing. The prefabricated block 35 is provided with a plurality of slots 31 matching the common positioning path of multiple units.

[0057] S6, such as Figure 6-7 As shown, the whole 3D printed prefabricated block 35 is installed on the repair base 20 on the prefabricated plaster model 40, and each repair base is inserted into the slot respectively, and the three-dimensional position of the repair base 20 installed on the plaster model 40 is consistent with the repair base 20 fixed in the mouth. We 3D optically scan the repair base 20 to prepare the 3D printed prefabricated block 35, so that we can select the appropriate cutting position outside the mouth to cut the 3D printed prefabricated block 35 in sections.

[0058] Subsequently, the prefabricated block 35 is positioned as a whole on the restoration base 20 on the plaster model 40, and the prefabricated block 35 is cut between multiple unit restoration bases. The size of the cutting gap is controlled during the cutting process to facilitate the secondary connection of the passive clamp in the mouth with as little self-curing resin as possible.

[0059] S7, such as Figure 8-9 As shown, each restoration base 20 on the plaster model 40 is removed and installed on the implant in the mouth, and then each cutting block 33 is inserted into the restoration base 20 in the mouth, and each printed material cutting block 33 is relatively fixed laterally on the restoration base 20. Finally, multiple printed material cutting blocks 33 are bonded together with self-curing resin 34 in the mouth to form the final passive position fixture 30, as shown in FIG. Fig.10 shown. Fig.11 This is a cross-sectional view of the passive position fixture installed in the mouth on a multi-implant restoration abutment (the adhesive part is not drawn). It can be seen that the inner wall of the slot 31 of the passive position fixture 30 fits with the outer wall of the upper section of the restoration abutment 20 in the mouth, and the insert 32 is embedded in the central through hole of the restoration abutment 20 and fits with the inner wall of the through hole, which can effectively ensure that the passive position fixture installed on the restoration abutment remains relatively fixed laterally. Therefore, when the passive position fixture 30 is put on the restoration abutment 20, the two are relatively fixed laterally and cannot be displaced.

[0060] If a notch 21 is provided at the upper end of the repair base 20, it is necessary to ensure that the insert 32 fits against the inner wall of the through hole while being exactly embedded in the notch 21, so as to further play a positioning and limiting role.

[0061] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can use the above-disclosed methods and technical contents to make many possible changes and modifications to the technical solutions of the present invention without departing from the scope of the technical solutions of the present invention, or modify them into equivalent embodiments of equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention are still within the scope of protection of the technical solutions of the present invention.

[0062] References:

[0063] [1](Lee H, So JS, Hochstedler JL, et al.The accuracy of implantimpressions:A systematic review[J].J Prosthet Dent, 2008, 100(4):285-291.)

[0064] [2](Osman MS, Ziada HM, Abubakr NH, et al. Implant impression accuracy of parallel and non-parallel implants: a comparative in-vitro analysis of open and closed tray techniques[J]. Int J Implant Dent, 2019, 5(1):4.)

[0065] [3](Filho HG,Mazaro JV,Vedovatto E,et al.Accuracy of ImpressionTechniques for Implants.Part 2-Comparison of Splinting Techniques[J].JProsthodont,2009,18(2):172-176.)(Papaspyridakos P,Benic GI,Hogsett VL,etal.Accuracy of implant casts generated with splinted and non-splintedimpression techniques for edentulous patients:an optical scanning study[J].Clin Oral Implants Res,2012,23(6):676-681.)(Naconecy MM,Teixeira ER,ShinkaiRSA,et al.Evaluation of accuracy of 3 transfer techniques for implant-supported prostheses with multiple abutments[J].Int J Oral MaxillofacImplants,2004,19(2):192-198.)

Claims

1. A method for taking impressions of multi-implant restoration based on a passive position fixture, wherein multiple implants are fixed on the gum bone, characterized in that: A columnar repair base is installed on each implant, and the repair base is provided with an axial through hole, and the inner wall and outer wall of the upper section of the repair base exposed to the soft tissue are both irregular surfaces; the passive position fixture is composed of an integral 3D printed prefabricated block that is cut into sections outside the mouth and reconnected with an adhesive inside the mouth, and each cutting block is provided with a slot, the inner wall contour of the slot matches the outer wall contour of the corresponding repair base, and an insert embedded in the through hole is provided in the slot, and the overall or partial outer contour of the insert matches the inner wall contour of the through hole; the upper section of the repair base is respectively inserted into each slot of the passive position fixture, the inner wall of the slot is fitted with the outer wall of the upper section of the repair base, and the insert is embedded in the through hole and fits with the inner wall of the through hole, so as to ensure that the passive position fixture installed on the repair base remains relatively fixed laterally, and the molding method comprises the following steps: S1. Use a transfer rod to make a preliminary impression of the position of multiple implants, and then make a plaster model containing multiple implant substitutes after reproducing the model; S2, selecting the repair abutment according to the plaster model of the multiple implants, and fixing each repair abutment on the implant substitute in the plaster model; S3. Perform preliminary grinding on the restoration abutment and find a common positioning path for multiple units; S4, performing 3D optical scanning on the restoration abutments to obtain digital information and three-dimensional positional relationship of each restoration abutment; S5, according to the digital information and the three-dimensional position relationship of each restoration base, using CAD-CAM to print out a whole prefabricated block, the prefabricated block is provided with a plurality of the slots; S6, installing the whole prefabricated block onto the repair base on the plaster model, and inserting each repair base into a corresponding slot, cutting the prefabricated block into a plurality of cutting blocks, wherein each cutting block is provided with a slot; S7, removing each restoration abutment on the plaster model and installing it on the implant in the mouth, inserting each cutting block into each restoration abutment in the mouth respectively, and bonding multiple cutting blocks together in the mouth to form the passive position fixture.

2. The mold taking method according to claim 1, wherein: A notch is provided on the upper side wall of the repair base, and the insert is embedded downwardly into the notch; The local width of the insert embedded in the notch is equivalent to the width of the notch.

3. The mold taking method according to claim 1, wherein: The binder is a self-curing resin.

4. The mold taking method as claimed in claim 3, characterized in that: Each of the repair abutments is fixed on a plaster model that is consistent with the position information of the intraoral implant, and a prefabricated block of resin material is integrally printed using CAD-CAM based on the 3D optical scanning position information of the repair abutment on the plaster model.

5. The mold taking method according to claim 1, characterized in that: The repair base is detachably mounted on the implant.

6. The mold taking method according to claim 5, characterized in that: The lower end of the repair base is inserted on the implant, a screw threadedly connected to the implant is arranged in the through hole, and a step for clamping the screw head is arranged on the inner wall of the through hole.

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