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WO2019153573A1 - 个性化牙科种植基台的增减材复合加工成型方法 - Google Patents

个性化牙科种植基台的增减材复合加工成型方法 Download PDF

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Publication number
WO2019153573A1
WO2019153573A1 PCT/CN2018/087870 CN2018087870W WO2019153573A1 WO 2019153573 A1 WO2019153573 A1 WO 2019153573A1 CN 2018087870 W CN2018087870 W CN 2018087870W WO 2019153573 A1 WO2019153573 A1 WO 2019153573A1
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Prior art keywords
abutment
personalized
substrate
cutting
semi
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PCT/CN2018/087870
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English (en)
French (fr)
Inventor
刘睿诚
张志霄
邹善方
吴利苹
姚圳珠
曾益伟
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成都优材科技有限公司
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Publication of WO2019153573A1 publication Critical patent/WO2019153573A1/zh

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A61C8/0048—Connecting the upper structure to the implant, e.g. bridging bars
    • A61C8/005—Connecting devices for joining an upper structure with an implant member, e.g. spacers
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A61C8/0048—Connecting the upper structure to the implant, e.g. bridging bars
    • A61C8/0077—Connecting the upper structure to the implant, e.g. bridging bars with shape following the gingival surface or the bone surface
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61C—DENTISTRY; APPARATUS OR METHODS FOR ORAL OR DENTAL HYGIENE
    • A61C8/00—Means to be fixed to the jaw-bone for consolidating natural teeth or for fixing dental prostheses thereon; Dental implants; Implanting tools
    • A61C8/0089—Implanting tools or instruments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/0093—Working by laser beam, e.g. welding, cutting or boring combined with mechanical machining or metal-working covered by other subclasses than B23K
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/34—Laser welding for purposes other than joining
    • B23K26/342—Build-up welding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y10/00—Processes of additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
    • B33Y40/20—Post-treatment, e.g. curing, coating or polishing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y50/00—Data acquisition or data processing for additive manufacturing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y80/00—Products made by additive manufacturing

Definitions

  • the invention relates to the field of additive manufacturing, in particular to the field of additive manufacturing dental implants, in particular to a method for composite processing of augmented and reduced materials of personalized dental implant abutments.
  • the implant abutment is the structural part of the dental implant that is exposed to the oral cavity through the gum.
  • the abutment is the connecting part between the implant and the superstructure.
  • the personalized planting abutment is customized according to the shape of the patient's gums, and has a good anatomical shape and correction angle; the abutment can best match the mechanical structure of the implant body, fit the anatomy of the gum around the implant, and is simple to manufacture and high in precision for the patient. And the doctor brings great convenience and becomes the repairing trend of future implant dentures.
  • the implant abutment usually includes a repair joint portion, an implant joint portion, and an interface.
  • repair joint portion refers to a portion of the implant abutment exposed to the oral cavity, and the crown is installed at the repair joint portion thereof.
  • the implant connection portion refers to the portion of the implant that is hidden in the gum, and the implant connection portion is provided with an interface for connection with the implant.
  • cobalt-chromium alloys and titanium alloy materials have excellent mechanical properties in terms of strength, hardness, wear resistance, and toughness, they have become the most commonly used materials for individualized planting abutments.
  • the commonly used dental metal implants are processed by mechanical cutting, and are cut on the basis of semi-finished abutments to obtain personalized abutments.
  • this molding method takes a long time, has low utilization rate of raw materials, and is lacking in precision.
  • the precision of bur cutting can reach 60 ⁇ m, and the accuracy and quality of the personalized dental implant abutment will be reduced due to the loss of the cutting bur.
  • the cutting needle can not be formed in the cutting process, adjacent The local precision is not good, so that the abutment and the implant, the abutment and the upper restoration cannot be precisely fitted, which affects the accuracy and the overall quality of the planting and restoration.
  • the cutting manufacturing method is not suitable for high-performance, automatic and rapid production of personalized planting abutments.
  • 3D printing is another name for additive manufacturing. It rebuilds the 3D digital model and uses the metal powder layer-by-layer principle to manufacture solid parts, making the entire manufacturing process truly intelligent and digital.
  • Laser selective melting is the most widely used laser selective melting technology. It is a technology based on laser melting metal powder. It integrates laser technology, digital intelligent control technology, computer aided design analysis and rapid prototyping. It can directly manufacture metallurgical bonding. Metal parts with compact structure, good mechanical properties and high precision.
  • the laser selective melting technology has the advantages of high degree of individuality, simple process, short production cycle and high material utilization rate, which can meet the technical requirements of personalized, complicated and difficult oral repair, and at the same time make up for the deficiencies of the prior art. Then worry about the effects of cutting temperature. Therefore, laser selective melting has been applied more and more to the manufacture of oral prostheses, and has become an indispensable emerging technology for oral digital processing.
  • the technical problem to be solved by the invention is to provide a composite processing method for increasing and reducing materials of a personalized dental implant abutment, combining the advantages of the two methods of additive manufacturing and material reduction to realize the high efficiency and high individualized abutment. Precision.
  • the method for composite processing of augmenting and reducing materials of a personalized dental implant abutment disclosed by the invention comprises the following steps:
  • Additive manufacturing manufacturing semi-finished products by additive manufacturing
  • the individual planting abutments are manufactured by cutting the semi-finished products of the abutments.
  • the substrate is designed, and the personalized implanting abutment is disposed on the substrate;
  • the semi-finished base on the substrate is cut by clamping the substrate;
  • the post-processing of the parts is performed to separate the individualized implanted abutments from the substrate to produce a personalized implanted base product.
  • At least two personalized planting abutments are provided on the same substrate.
  • the implant connection portion and the interface of the semi-finished base are cut.
  • the repair connection portion of the personalized planting abutment is disposed close to the substrate, so that the implant connecting portion of the personalized planting abutment is away from the substrate.
  • the cutting allowance added to the implant connecting portion and the interface of the personalized planting abutment is 0.6-0.8 mm.
  • the positioning table is processed by the additive manufacturing on the substrate
  • the positioning needle of the cutting device is inserted into the positioning table to determine the precise position of the semi-finished base on the substrate.
  • one of the right-angled sides of the right-angled triangle formed by the positioning table is parallel to the X-axis of the cutting device, and the other right-angled side is parallel to the Y-axis.
  • a gap of 0.04-0.05 mm is left between the positioning hole of the positioning table and the positioning needle of the cutting device.
  • a support structure is added between the substrates on the personalized planting base;
  • the support structure is processed by additive manufacturing.
  • the support structure is a small cross support, and the small cross support comprises two crisscross support bars.
  • the length of the support bar of the small cross support is 0.6-0.9 mm, and the distance between adjacent small cross supports is 0.4-0.6 times of the length of the support bar.
  • the material used for the personalized planting abutment is pure titanium, titanium alloy or cobalt chromium alloy.
  • the laser selective melting technique is used for the additive manufacturing, and the chessboard partition scanning strategy is adopted in the laser selective melting process.
  • the thickness of each slice is 0.02-0.03 mm during the slicing process required for the additive manufacturing of the semi-finished base 6 .
  • the invention Compared with the existing semi-finished abutment direct cutting method, the invention has the following beneficial effects:
  • the design of the personalized abutment can be processed without any limitation of the shape of the semi-formed abutment, and the personalized abutment of any complicated shape can be processed;
  • the invention Compared with the existing additive manufacturing method, the invention has the following beneficial effects:
  • the present invention is applicable to cobalt chromium alloys, titanium and titanium alloys, and the like, and a wider range of materials are available.
  • Figure 4 is a schematic view of a small cross support.
  • the method for composite processing of augmenting and reducing materials of a personalized dental implant abutment disclosed by the invention comprises the following steps:
  • Design a personalized planting abutment design a personalized planting abutment based on the case.
  • the existing personalized planting abutment can be used.
  • the specific design method can adopt three-dimensional scanning, and the three-dimensional design based on the scanning result is designed to design a personalized planting abutment adapted to the case situation.
  • the individual planting abutments are manufactured by cutting the semi-finished products of the abutments.
  • data for processing the semi-finished base 6 into a final product by means of material reduction is also obtained, and with these data, the semi-finished base 6 can be cut into a designed individual planting abutment.
  • the substrate 7 is designed, and the personalized implanting abutment is disposed on the substrate 7;
  • the semi-finished base 6 is processed by the additive on the substrate;
  • the semi-finished base 6 on the substrate 7 is cut by the clamping substrate 7;
  • the post-processing of the parts is performed, and the individualized implant abutments after cutting are separated from the substrate 7 to produce a personalized planting base product.
  • the personalized planting abutment is disposed on the substrate 7, which not only facilitates the clamping of the material cutting, but also helps maintain the stability during the additive manufacturing process, but after the substrate 7 is set, an additional part post-processing step is provided.
  • the personalized planting abutment is separated from the substrate 7 to obtain a finished product.
  • the personalized planting abutments that can be placed on the same substrate 7 are not limited to one, but two or more personalized planting abutments can be placed, and these personalized planting abutments can simultaneously Processing, saving a lot of manpower, reducing human error, and improving the processing efficiency of personalized planting abutments.
  • the cutting allowance is designed on the implant connecting portion 9 and the interface 10 of the personalized planting abutment, and the semi-finished base 6 is designed; when the material is reduced, the implant connecting portion 9 of the semi-finished base 6 is manufactured. And the interface 10 performs cutting processing. Only the implant connection portion 9 and the interface 10, which require high surface precision, increase the cutting allowance and perform cutting processing, which not only can effectively save materials, but also can reduce the processing difficulty and improve the processing efficiency.
  • the cutting allowance 4 of the abutment implant connecting portion 9 and the cutting allowance 5 of the abutment interface 10 are preferably 0.6-0.8 mm.
  • the personalized planting abutment is placed on the substrate 7, and the personalized planting abutment must have a part directly or indirectly connected to the substrate 7, in order to facilitate the implant connecting portion of the semi-finished base 6 9 and the cutting process of the interface 10, the repair connection portion 8 of the personalized planting abutment is placed close to the substrate 7, so that the implant connecting portion 9 of the personalized planting abutment is away from the substrate 7.
  • the personalized planting abutment is placed upside down on the substrate 7, so that the implant connecting portion 9 and the interface 10 portion of the personalized planting abutment can be better precision cut to obtain a higher surface. Precision.
  • the substrate 7 can not only provide a clamping function in cutting, but also realize a positioning effect.
  • a positioning platform is added on the substrate 7, and the positioning platform is provided with a positioning hole, and the positioning is performed.
  • the hole is matched with the positioning bur of the cutting device; when the additive is manufactured, the positioning table is manufactured by the additive manufacturing on the substrate 7; when the material is reduced, the positioning needle of the cutting device is inserted into the positioning table to determine The precise position of the semi-finished base 6 on the substrate 7.
  • the positioning hole of the positioning table is adapted to the positioning needle of the precision cutting, and the gap of 0.04-0.05 mm is usually left on the basis of the position of the locating needle into the positioning table.
  • the number of positioning stations may be one or more, but in order to enable a better positioning effect, the number of positioning platforms is three, and the three positioning platforms are arranged in a triangle to ensure accurate positioning on the horizontal plane. Sex, and there will be no reverse installation problems like the two positioning stations. Furthermore, the role of the positioning table is to locate the X-axis direction and the Y-axis direction. If the two directions are clearly positioned, it is more conducive to the design and control of the cutting process.
  • the specific method is three positioning tables during data processing.
  • one of the right-angled sides of the right-angled triangle formed by the positioning table is parallel to the X-axis of the cutting device, and the other right-angled side is parallel to the Y-axis. For example, as shown in FIG.
  • the substrate 7 is respectively provided with a positioning platform 1, a positioning platform 2, and a positioning platform 3, and the length ratio of the two right sides of the right triangle formed by the three positioning tables is set to 3: 4, wherein the right angle side formed by the second positioning table 2 and the third positioning table 3 is a long side, and along the X axis direction, the right angle side formed by the first positioning table 1 and the second positioning table 2 is a short side along the Y axis
  • the orientation can ensure the positioning of the substrate 7 on the X-axis and the Y-axis, determine the precise position of the components on the substrate 7, and combine the positioning of the central axis of the interface with the Z-axis to achieve an all-round positioning effect. Provides effective protection for cutting.
  • the personalized planting abutment should not be directly connected to the substrate 7, and the direct connection is not convenient for the separation of the two, and may affect the surface quality of the personalized implanted abutment support surface. Therefore, it is preferable to add a support structure between the substrate 7 in the personalized planting base.
  • the support structure can adopt various structures. In the embodiment shown in FIG. 4, in the data processing, the implant base and the substrate 7 are personalized.
  • a small cross support is provided, the small cross support comprising two crisscross support bars.
  • the length of the small cross support is preferably 0.6-0.9 mm, and the distance between the adjacent small cross supports is 0.4-0.6 times the length of the small cross support, where the separation distance refers to the closest between the two adjacent small cross supports.
  • the small cross support is relatively easy to remove and reduces the post-treatment of the part. It should be noted that the support structure cannot be added to the internal circular hole and step area of the personalized planting abutment to prevent the support structure from affecting the surface precision.
  • additive manufacturing there are many types of additive manufacturing, such as laser stereo printing technology based on polymer polymerization, polymer printing technology, micro-stereo printing, etc.
  • Selective laser sintering technology based on sintering and melting, laser selection Melting technology, electron beam melting technology, etc.
  • the combination of the corresponding materials can be used to print a personalized implant abutment.
  • the present invention employs laser selective melting technology for additive manufacturing, and employs a checkerboard partition scanning strategy, as embodied by:
  • the semi-finished base 6 is designed, the semi-finished base 6 is subjected to additive manufacturing, and the thickness of each layer is 0.02-0.03 mm.
  • the metal powder of each cross-sectional area of the substrate 7 is melt-molded by laser scanning of a 3D printing apparatus by a laser-selected molten metal metal 3D printing apparatus using micron-sized spherical metal powder as a material, and then The layers are superimposed as metal parts; the individualized planting abutments, support structures and positioning tables are machined, and the entire substrate 7 is removed for use.
  • the laser scanning melting process uses a checkerboard partition scanning, which divides the section of the part into a plurality of squares, and the laser performs an "S"-shaped scanning in each square.
  • the order in which the laser completes each square fill is random, that is, the temperature field changes for each section are random.
  • Designing a personalized planting abutment Using a conventional dental digital processing method, a personalized planting abutment is designed according to the case.
  • Data processing processing the data of the personalized planting abutment, and finally obtaining two kinds of data suitable for both additive manufacturing and material reduction manufacturing;
  • Additive manufacturing The individualized abutment, support structure and positioning table are processed, and the whole molded substrate 7 is taken out for use.
  • the substrate 7 finished by laser additive manufacturing is placed on the fixture of the precision cutting equipment to complete the precision cutting process.
  • the material reduction manufacturing steps include needle positioning and precision machining.

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Abstract

一种个性化牙科种植基台的增减材复合加工成型方法。个性化牙科种植基台的增减材复合加工成型方法，包括如下步骤：设计个性化种植基台：根据病例情况设计出个性化种植基台；数据处理：对个性化种植基台上需要切削加工的部分设计切削余量，对基台进行增材制造所需的切片处理，并规划基台进行切削加工的切削刀路；增材制造：通过增材制造加工出基台半成品；减材制造：对基台半成品切削加工制造出个性化种植基台。该加工成型方法将增材制造和减材两种方式的优势结合起来，实现个性化种植基台的高效和高精度，其适用于钴铬合金，钛及钛合金等，可选用的材料范围更加广泛。

Description

个性化牙科种植基台的增减材复合加工成型方法 技术领域
本发明涉及增材制造领域，尤其是增材制造牙科种植领域，具体地，是一种个性化牙科种植基台的增减材复合加工成型方法。
背景技术
牙科种植手术是目前牙体缺失最有效的修复方式，其中种植体基台是牙种植体穿过牙龈暴露于口腔中的结构部分，基台是植入体和上部结构之间的连接部分。个性化种植基台根据患者牙龈的形态定制，拥有良好的解剖外形和修正角度；基台能最大程度地配合种植体内的机械结构、适合种植体周围牙龈解剖形态，制作简便、精度高，为患者和医生带来极大的便利，成为未来种植义齿的修复趋势。从结构上来讲，种植体基台通常包括修复连接部分、种植体连接部分及接口，所谓修复连接部分即是指种植体基台暴露于口腔中的部分，牙冠即是安装于其修复连接部分上；种植体连接部分即是指种植体其隐藏于牙龈中的部分，种植体连接部分设置有接口，用于与植入体相连接。
由于钴铬合金和钛合金材料在强度、硬度、耐磨性、和韧性方面具有优良的力学性能，因此成为了个性化种植基台最常用的材料。
目前常用的牙科金属种植支架的加工方式为机械切削法，在半成品基台的基础上进行切削，得到个性化基台。但这种成型方式耗时长、原材料利用率低，而且在精度方面欠缺。目前车针切削的精度最高能达到60μm级别，且个性化牙科种植基台的精确度和质量会因切削车针损耗而变低，切削过程中车针切削不到的地方无法成型，相邻的地方精度不佳，使基台与种植体、基台与上部修复体之间无法精密贴合，影响精度和种植修复的总体质量。而且半成品基台切削过程中，经常出现半成品基台无法满足个性化基台形态的情况。因此切削制造的加工方法已经不适合进行高性能、自动快速的制作个性化种植基台。
3D打印是增材制造的别称，其通过重建设计三维数字化模型，采用金属粉末逐层累加原理制造实体零件，让整个制造过程真正实现了智能化与数字化。激光选区熔化是应用最广泛的激光选区熔化技术，它是一种基于激光熔化金属粉末的技术，集激光技术、数字智能化控制技术、计算机辅助设计分析、快速成型于一体，能直接制造冶金结合、组织致密、力学性能良好、精度高的金属零部件。
其中，激光选区熔化技术具有个性化程度高、工序简单、制作周期短、材料利用率高等优点，可以满足口腔修复个性化、复杂化、高难度的技术要求，同时弥补现有技术的不足，不必再担心因为切削温度带来的种种影响。因此激光选区熔化已经越来越多的被应用到口腔 修复体的制造当中，成为了口腔数字化加工不可或缺的新兴技术。
但是激光选区熔化在加工金属材料时，因为骤热骤冷的成型机理，种植支架在加工过程中热应力大，容易变形；对加工的种植支架添加了支撑进行3D打印后，零件后处理比较费时，且容易影响与种植体的接口处的精度，因此采用激光选区熔化直接加工个性化种植基台难度很大。由于目前采用激光选区熔化的零件通常要求精度不高，在一次性激光扫描后零件边缘有毛刺等不平滑结构，这也是在牙科种植基台中不允许的。
发明内容
本发明所要解决的技术问题是提供一种个性化牙科种植基台的增减材复合加工方法，将增材制造和减材两种方式的优势结合起来，实现个性化种植基台的高效和高精度。
本发明公开的个性化牙科种植基台的增减材复合加工成型方法，包括如下步骤：
设计个性化种植基台：根据病例情况设计出个性化种植基台；
数据处理：对个性化种植基台上需要切削加工的部分设计切削余量，设计出半成品基台，对半成品基台进行增材制造所需的切片处理，并规划对出半成品基台进行切削加工的切削刀路；
增材制造：通过增材制造加工出基台半成品；
减材制造：对基台半成品切削加工制造出个性化种植基台。
优选地，数据处理时，设计基板，将个性化种植基台设置于基板上；
增材制造时，在基板上通过增材制造加工出半成品基台；
减材制造时，通过夹持基板对基板上的半成品基台进行切削加工；
减材制造后，进行零件后处理，将切削后的个性化种植基台与基板相分离，制造出个性化种植基台成品。
优选地，同一基板上设置至少两个个性化种植基台。
优选地，数据处理时，在个性化种植基台的种植体连接部分及接口设计切削余量，设计出半成品基台；
减材制造时，对半成品基台的种植体连接部分及接口进行切削加工。
优选地，数据处理时，将个性化种植基台的修复连接部分靠近基板设置，使个性化种植基台的种植体连接部分远离基板。
优选地，数据处理时，在个性化种植基台的种植体连接部分及接口添加的切削余量厚度为0.6-0.8mm。
优选地，数据处理时，通过调整基板与个性化种植基台的相对位置，确保基板在切削夹持状态下个性化种植基台的接口中心轴与切削设备的Z轴相平行。
优选地，数据处理时，在基板上添加定位台，所述定位台上设置有定位孔，所述定位孔与切削设备的定位车针相适配；
增材制造时，在基板上通过增材制造加工出定位台；
减材制造时，将切削设备的定位车针伸入定位台内，确定出基板上半成品基台的精确位置。
优选地，所述定位台的数量为三个，三个定位台呈三角形排布。
优选地，数据处理时，三个定位台呈直角三角形排布；
基板在切削夹持状态时，定位台形成的直角三角形的其中一个直角边与切削设备的X轴相平行，另一直角边与Y轴相平行。
优选地，定位台的定位孔与切削设备的定位车针之间留有0.04-0.05mm的间隙。
优选地，数据处理时，在个性化种植基台于基板之间添加支撑结构；
增材制造时，通过增材制造加工出支撑结构。
减材制造后，进行零件后处理，在线切割、去除支撑结构和打磨后，制造出个性化种植基台成品。
优选地，所述支撑结构为小十字支撑，所述小十字支撑包括两条十字交叉的支撑条。
优选地，所述小十字支撑的支撑条长度为0.6-0.9mm，相邻小十字支撑之间的间隔距离为支撑条长度的0.4-0.6倍。
优选地，所述个性化种植基台采用的材料为纯钛、钛合金或者钴铬合金。
优选地，增材制造时，采用激光选区熔化技术进行增材制造，在激光选区熔化过程中采用棋盘分区扫描策略。
优选地，对半成品基台6进行增材制造所需的切片处理过程中，每层切片的厚度为0.02-0.03mm。
本发明相比于现有的半成品基台直接切削的方法，具有以下有益效果：
(1)个性化基台的设计可以不受既定的半成型基台形状大小的限制，加工出任意复杂形状的个性化基台；
(2)能够节约更多材料，具有更高的精度和力学性能；
(3)根据针对性设计的个性化种植基台而增材加工出的半成品基台，更易于切削加工，可以有效提高加工效率。
本发明相比于现有的增材制造个性化种植基台方法，具有以下有益效果：
(1)通过增材和减材复合加工的方法可以有效提高个性化种植基台的精度；
(2)可以有效避免个性化种植基台的边缘出现毛刺等不平滑结构。
此外，本发明适用于钴铬合金，钛及钛合金等，可选用的材料范围更加广泛。
附图说明
图1为个性化牙科种植基台的增减材复合加工成型方法的一个实施例的流程图；
图2为个性化基台增减材复合加工的数据处理排版图；
图3为增减材复合加工成型后的个性化种植基台的示意图；
图4为小十字支撑的示意图。
附图标记：一号定位台1，二号定位台2，三号定位台3，基台种植体连接部分切削余量4，基台接口切削余量5，半成品基台6，基板7，修复连接部分8，种植体连接部分9，接口10。
具体实施方式
下面对本发明进一步说明。
本发明公开的个性化牙科种植基台的增减材复合加工成型方法，包括如下步骤：
设计个性化种植基台：根据病例情况设计出个性化种植基台。
采用现有的个性化种植基台的方式即可，具体的设计方式可以采用三维扫描，基于扫描结果进行三维设计，设计出适应病例情况的个性化种植基台。
数据处理：对个性化种植基台上需要切削加工的部分设计切削余量，设计出半成品基台6，对半成品基台6进行增材制造所需的切片处理，并规划对出半成品基台6进行切削加工的切削刀路；
数据处理的目的在于最终获得同时适用于增材制造和减材制造的两种数据，简而言之，就是通过增材制造加工出半成品基台6和通过减材制造将半成品基台6加工成最终产品的数据。具体方式如上所述，在设计出的个性化基台的基础上，选取需要切削精加工的位置增加切削余量，设计出半成品基台6，对半成品基台6进行切片处理，获得增材制造加工出半成品基台6的数据，设计过程中可以考虑兼顾增材制造对半成品基台6微调。然后规划出由半成品基台6至成品的切削刀路，获得从半成品基台6加工出成品个性化种植基台的数据，在实际设计时，还可以从切削的效率、精度以及耗材方面，反向微调半成品基台6的形状与和结构。
增材制造：通过增材制造加工出基台半成品；
在数据处理中已经获得了增材制造加工出半成品基台6的数据，利用这些数据即可通过增材制造出半成品基台6。
减材制造：对基台半成品切削加工制造出个性化种植基台。
在数据处理中同时获得了通过减材制造将半成品基台6加工成最终产品的数据，利用这 些数据即可将半成品基台6切削成为所设计的个性化种植基台。
由于个性化种植基台的尺寸较小，且对于表面精度要求很高，因此在切削过程中切削设备很难对其进行很好地夹持，进而影响切削加工的正常进行。为此，在上述方案的技术上，进行了如下改进：
数据处理时，设计基板7，将个性化种植基台设置于基板7上；
增材制造时，在基板上通过增材制造加工半成品基台6；
减材制造时，通过夹持基板7对基板7上的半成品基台6进行切削加工；
减材制造后，进行零件后处理，将切削后的个性化种植基台与基板7相分离，制造出个性化种植基台成品。
将个性化种植基台设置于基板7上，不但可以方便减材切削的夹持，而且有助于增材制造过程中保持其稳定性，不过设置基板7后就多了一项零件后处理步骤，将个性化种植基台从基板7上分离出来获得成品。在设置基板7后，同一个基板7上所能摆放的个性化种植基台就不仅限于一个了，而可以摆放两个以上的个性化种植基台，这些个性化种植基台可以实现同时加工，节省了大量人力，减少人为误差，提高了个性化种植基台的加工效率。
数据处理时，可以在个性化种植基台原设计的技术上整体增加切削余量设计出半成品基台6，增材制造后对其进行整体切削，这样加工出来的个性化种植基台的精度最高，不过相对而言，加工难度较大和效率较低。实际上个性化种植基台的而修复连接部分8用于安装牙冠，精度要求相对较低，增材制造的精度就能符合要求，而其种植体连接部分9及接口10，因为需要直接与牙龈接触以及与植入体对接，对于表面精度要求更高，仅增材制造可能就无法满足其精度要求了。为此，数据处理时，在个性化种植基台的种植体连接部分9及接口10设计切削余量，设计出半成品基台6；减材制造时，对半成品基台6的种植体连接部分9及接口10进行切削加工。仅对表面精度要求高的种植体连接部分9及接口10增加切削余量并进行切削处理，不但可以有效节省材料，而且可以降低加工难度，提高加工效率。如图2所示，其中，基台种植体连接部分9切削余量4和基台接口10切削余量5均优选为0.6-0.8mm。
在设置了基板7的情况下，个性化种植基台摆放于基板7上，个性化种植基台必须要有一部分直接或间接与基板7相连接，为了方便半成品基台6的种植体连接部分9及接口10的切削加工，将个性化种植基台的修复连接部分8靠近基板7设置，使个性化种植基台的种植体连接部分9远离基板7。换句话将即是个性化种植基台是倒立设置于基板7上的，从而使个性化种植基台的种植体连接部分9及接口10部分能更好地进行精密切削，获得更高的表面精度。
此外，为了更好地进行切削加工，数据处理时，确保基板7在切削夹持状态下个性化种 植基台的接口中心轴与切削设备的Z轴相平行。切削设备通常具有X、Y、Z三个轴方向，X轴和Y轴均位于水平面上且相互垂直，Z轴则垂直于水平面，通过数据处理时调整基板7与接口中心轴之间的角度来实现接口中心轴与切削设备的Z轴相平行。例如基板7在切削夹持时，与切削设备的Z轴是相垂直的，那么设置接口中心轴与基板7相垂直，即可确保切削时接口中心轴与Z轴平行。
基板7不但可以在切削是提供夹持作用，而且还能实现定位效果，为了使其实现定位，数据处理时，在基板7上添加定位台，所述定位台上设置有定位孔，所述定位孔与切削设备的定位车针相适配；增材制造时，在基板7上通过增材制造加工出定位台；减材制造时，将切削设备的定位车针伸入定位台内，确定出基板7上半成品基台6的精确位置。定位台的定位孔与精密切削的定位车针相适应，通常在位车针伸入定位台内的基础上，留有0.04-0.05mm的间隙。
定位台的数量可以是一个或者多个，但是为了使其能够发挥更好的定位效果，所述定位台的数量为三个，三个定位台呈三角形排布，可以确保水平面上的定位的准确性，且不会如两个定位台一样出现安装反向问题。更进一步来讲，定位台的作用是定位X轴方向和Y轴方向，将此两个方向明确定位出来则，更有利于切削加工的设计与控制，具体方式是数据处理时，三个定位台呈直角三角形排布；基板7在切削夹持状态时，定位台形成的直角三角形的其中一个直角边与切削设备的X轴相平行，另一直角边与Y轴相平行。例如图2所示，基板7上分别设置有一号定位台1，二号定位台2，三号定位台3，将三个定位台构成的直角三角形的两条直角边长度比设定为3：4，其中，二号定位台2和三号定位台3形成的直角边为长边，沿X轴方向，一号定位台1和二号定位台2形成的直角边为短边，沿Y轴方向，如此即可保证基板7在X轴和Y轴上的定位，确定出基板7上零件的精确位置，再结合前述的接口中心轴与Z轴的定位，从而实现了全方位的定位效果，为切削加工提供了有效的保障。
在设置有基板7的情况下，个性化种植基台不宜与基板7直接连接，直接连接不便于两者的相互分离，而且可能会影响个性化种植基台支撑面的表面质量。因此，优选在个性化种植基台于基板7之间添加支撑结构，支撑结构可以采用多种结构，如图4所示的实施例中，数据处理时，在个性化种植基台与基板7之间设置小十字支撑，所述小十字支撑包括两条十字交叉的支撑条。小十字支撑的长度优选为0.6-0.9mm，相邻小十字支撑之间的间隔距离为小十字支撑长度的0.4-0.6倍，这里的间隔距离是指相邻两个小十字支撑之间最接近的部分的距离；减材制造后，进行零件后处理，线切割、去除小十字支撑和打磨后，制造出个性化种植基台成品。小十字支撑相对更加容易去除，可减少零件后处理工序。需要注意的是在个性化种植基台的内部圆孔和台阶区域不能加支撑结构，防止支撑结构影响表面精度。
增材制造有多种类型，如以高分子聚合反应为基本原理的激光立体印刷技术、高分子打印技术、微型立体印刷术等，以烧结和熔化为基本原理的选择性激光烧结技术、激光选区熔化技术、电子束熔化技术等等。结合选取对应的材料均可用于打印个性化种植基台。但是作为优选方式，本发明采用激光选区熔化技术进行增材制造，并且采用棋盘分区扫描策略，具体实施例如下：
数据处理时，在设计出半成品基台6后，对半成品基台6进行增材制造的切片设计，每层的厚度为0.02-0.03mm。
增材制造时，通过激光选区熔化的金属3D打印设备，以微米级的球形金属粉末为材料，通过3D打印设备的激光扫描熔化成型基板7的每一层截面区域的所述金属粉末，再逐层叠加为金属零件；将个性化种植基台、支撑结构和定位台都加工出来，取下整块基板7备用。
其中所述激光扫描熔化过程采用棋盘分区扫描，棋盘分区扫描是将零件的截面分割成若干个正方形，激光在每个正方形内进行“S”形扫描。激光完成每个正方形填充的顺序是随机的，也就是说，每个截面的温度场变化都是随机的。这种策略减少基台成型过程的热应力，使得零件后处理部分不需要进行去应力退火处理，简化了成型工序。
如图1所示，即为本发明的一个优选实施例的流程图。
具体流程如下：
设计个性化种植基台：采用常规牙科数字化加工的方法，根据病例情况设计出个性化种植基台。
数据处理：将个性化种植基台的数据进行处理，最终获得同时适用于增材制造和减材制造的两种数据；
数据处理过程包括：个性化基台的位置摆放、支撑结构添加、添加定位台、为基台种植体连接部分9和接口10设计切削余量、增材制造切片、减材制造切削刀路规划。
增材制造：将个性化种植基台、支撑结构和定位台都加工出来，取下整块成型基板7备用。
减材制造：将激光增材制造加工完成的基板7，放在精密切削设备的夹具上，完成精密切削加工。减材制造步骤包括车针定位和精密切削加工。
零件后处理：线切割、去除支撑和打磨后，得到一份个性化种植基台。

Claims (17)

  1. 个性化牙科种植基台的增减材复合加工成型方法，其特征在于，包括如下步骤：
    设计个性化种植基台：根据病例情况设计出个性化种植基台；
    数据处理：对个性化种植基台上需要切削加工的部分设计切削余量，设计出半成品基台(6)，对半成品基台(6)进行增材制造所需的切片处理，并规划对出半成品基台(6)进行切削加工的切削刀路；
    增材制造：通过增材制造加工出基台半成品；
    减材制造：对基台半成品切削加工制造出个性化种植基台。
  2. 如权利要求1所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，设计基板(7)，将个性化种植基台设置于基板(7)上；
    增材制造时，在基板上通过增材制造加工出半成品基台(6)；
    减材制造时，通过夹持基板(7)对基板(7)上的半成品基台(6)进行切削加工；
    减材制造后，进行零件后处理，将切削后的个性化种植基台与基板(7)相分离，制造出个性化种植基台成品。
  3. 如权利要求2所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：同一基板(7)上设置至少两个个性化种植基台。
  4. 如权利要求2所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，在个性化种植基台的种植体连接部分(9)及接口(10)设计切削余量，设计出半成品基台(6)；
    减材制造时，对半成品基台(6)的种植体连接部分(9)及接口(10)进行切削加工。
  5. 如权利要求4所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，将个性化种植基台的修复连接部分(8)靠近基板(7)设置，使个性化种植基台的种植体连接部分(9)远离基板(7)。
  6. 如权利要求4所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，在个性化种植基台的种植体连接部分(9)及接口(10)添加的切削余量厚度为0.6-0.8mm。
  7. 如权利要求2所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，通过调整基板(7)与个性化种植基台的相对位置，确保基板(7)在切削夹持状态下个性化种植基台的接口中心轴与切削设备的Z轴相平行。
  8. 如权利要求2或7所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在 于：
    数据处理时，在基板(7)上添加定位台，所述定位台上设置有定位孔，所述定位孔与切削设备的定位车针相适配；
    增材制造时，在基板(7)上通过增材制造加工出定位台；
    减材制造时，将切削设备的定位车针伸入定位台内，确定出基板(7)上半成品基台(6)的精确位置。
  9. 如权利要求8所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：所述定位台的数量为三个，三个定位台呈三角形排布。
  10. 如权利要求9所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：
    数据处理时，三个定位台呈直角三角形排布；
    基板(7)在切削夹持状态时，定位台形成的直角三角形的其中一个直角边与切削设备的X轴相平行，另一直角边与Y轴相平行。
  11. 如权利要求8所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：定位台的定位孔与切削设备的定位车针之间留有0.04-0.05mm的间隙。
  12. 如权利要求2所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：数据处理时，在个性化种植基台于基板之间添加支撑结构；
    增材制造时，通过增材制造加工出支撑结构；
    减材制造后，进行零件后处理，在线切割、去除支撑结构和打磨后，制造出个性化种植基台成品。
  13. 如权利要求12所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：所述支撑结构为小十字支撑，所述小十字支撑包括两条十字交叉的支撑条。
  14. 如权利要求13所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：所述小十字支撑的支撑条长度为0.6-0.9mm，相邻小十字支撑之间的间隔距离为支撑条长度的0.4-0.6倍。
  15. 如权利要求1所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：所述个性化种植基台采用的材料为纯钛、钛合金或者钴铬合金。
  16. 如权利要求1所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：增材制造时，采用激光选区熔化技术进行增材制造，在激光选区熔化过程中采用棋盘分区扫描策略。
  17. 如权利要求1所述的个性化牙科种植基台的增减材复合加工成型方法，其特征在于：对半成品基台6进行增材制造所需的切片处理过程中，每层切片的厚度为0.02-0.03mm。
PCT/CN2018/087870 2018-02-08 2018-05-22 个性化牙科种植基台的增减材复合加工成型方法 WO2019153573A1 (zh)

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