CN112245047A

CN112245047A - Method for preparing oral functional jaw pad by combining hot-pressing film and 3D direct printing

Info

Publication number: CN112245047A
Application number: CN202010921484.9A
Authority: CN
Inventors: 郭维华; 韩雪; 张家愚; 陈杰; 廖利君; 肖静宜
Original assignee: Sichuan University
Current assignee: Chengdu Gedengte Technology Co ltd
Priority date: 2020-04-24
Filing date: 2020-09-04
Publication date: 2021-01-22
Anticipated expiration: 2040-09-04
Also published as: CN112245047B

Abstract

The invention discloses a method for directly preparing a dental function jaw pad by combining hot-pressing film and 3D printing, which is characterized by comprising the following steps of: obtaining three-dimensional data and occlusion records of dental arches of patients, importing dentition data into 3D image processing software to construct models, connecting a 3D printer to print and solidify the dentition models, and manufacturing a retention device of a dental pad by adopting a positive pressure hot-pressing film technology. The invention combines the advantages of elasticity, thin thickness and good tooth fitting property of the diaphragm manufactured by the hot pressing film technology and the advantages of high precision of the oral functional jaw pad manufactured by 3D printing, has the advantages of quick and direct molding, short manufacturing period, high precision, low cost, small difficulty and the like, and the manufactured jaw pad can effectively solve the problem that the tooth lacking gap is difficult to reserve in the manufacturing process of the tooth replacing jaw pad.

Description

Method for preparing oral functional jaw pad by combining hot-pressing film and 3D direct printing

Technical Field

The invention belongs to the field of oral surgery, and particularly relates to a method for preparing an oral functional dental pad by combining a hot pressing film technology and 3D direct printing, which is rapid and direct in forming and is suitable for clinical orthodontics, repairs, joints, oral maxillofacial surfaces and the like.

Background

The technology of the dental jaw pad is always an important part for clinical use of the oral cavity, and the dental jaw pad is mainly distributed in the aspects of jaw position diagnostic repair, occlusion interference elimination, jaw position treatment and the like in the clinical application of the oral cavity, in particular to the most conventional treatment modes of an oral joint department, an orthodontic department, a repair department and an oral and maxillofacial surgery.

At present, the dental jaw pad is mainly applied to oral clinical application and relates to the following aspects that in the department of oral joint, a slightly harder jaw pad is needed, such as a molar jaw pad at night, a loose jaw pad, a joint jaw position reconstruction jaw pad and the like, to treat bilateral temporomandibular joint diseases. Secondly, for the department of restoration, a jaw pad with high hardness is needed to meet the requirements of complete denture restoration or severe abrasion dentition restoration. And thirdly, in the field of orthodontics, under the conditions of front tooth anti-jaw, back tooth locking jaw and the like, the teeth are moved and corrected after being occluded by using a soft jaw pad. And fourthly, in particular to the invisible correcting technology, the proper stress of the teeth is assisted by the soft jaw pad without influencing the taking and wearing of the correcting device, and the like. In the early correcting process of children, the soft jaw pad is opened to be occluded, so that jaw position reconstruction can be performed, and adaptation to children is facilitated. In the oral maxillofacial surgery, particularly in the orthognathic surgery field, the preparation and positioning of the jaw bone and the improvement of the facial form by a relatively hard jaw pad play a great role. Therefore, the jaw pad has wide and high applicability in various fields of the oral cavity, but different functions determine different hardness requirements of the jaw pad.

At present, the jaw pad is made of a high polymer resin material with soft and hard surfaces, is pressurized at high temperature and pressed to form once, has a thickness of only about 2 millimeters, ensures the strength of the jaw pad, has the advantages of the soft jaw pad, can keep the normal occlusion relation of children, ensures the uniform distribution of the occlusal surface, and is more comfortable for children to feel when in use. The mechanism of action is that the direct contact between the upper and lower teeth is mechanically isolated, the jaw force is redistributed, and the chewing collision pressure is buffered, so that the teeth of children are prevented from being ground, and the tooth bodies and the periodontal tissues are prevented from being continuously damaged.

The clinical manufacturing of soft jaw cushions and the preparation of technicians are relatively complicated. The preparation process of the conventional functional jaw pad is relatively complicated, firstly, after the occlusal relation is obtained in the oral cavity of a patient through paraffin or silicon rubber, the upper jaw and the lower jaw are transferred to a fully adjustable jaw frame through a facial arch and the like, then, a dental resin base is filled on a retention device such as a dentition hot-pressing film or a snap ring and the like, then, the corrected and manufactured dentognathic and maxillofacial base is confirmed through the jaw frame, and finally, grinding and polishing are carried out. This method not only requires the clinician to have higher jaw frame relation transfer operation technique, but also needs the expensive and complicated fully adjustable jaw frame to correct, the clinical operation difficulty is large, for the functional jaw pad requiring the fine occlusion reconstruction, the multi-step subjective technique is extremely troublesome and laborious, the flow is complicated and the error is extremely easy, the adjustment is needed in the later stage, the further preparation flow and the accuracy improvement are needed to reach the practical requirement.

The 3D printing technology is widely used in bioengineering, construction engineering and the like due to the characteristics of high efficiency, accuracy and the like, but due to the limitation of material performance, no matter DLP (digital light processing) or SLA laser rapid prototyping or FDM 3D printing, a printed sample has the technical problems of high hardness, poor elasticity and the like, and is very difficult to take and wear for patients with teeth undercut.

Disclosure of Invention

Aiming at the problems, the invention provides a method for preparing an oral function dental pad by combining a hot pressing film technology and 3D direct printing, and the oral function dental pad is prepared by combining the hot pressing film technology and the 3D direct printing, so that the defects of complicated preparation process, high difficulty, large volume, uncomfortable wearing and the like of the traditional functional pad are overcome; the prepared dental jaw pad has short clinical operation time, simple process, small volume, easy wearing and taking and accurate occlusion so as to meet the clinical requirement; the manufactured dental jaw pad is soft and high in bullet head, and meets the requirements of target groups.

The method for preparing the dental function jaw pad by combining the hot pressing film technology and the 3D direct printing solves the technical problems, and is characterized in that: the method is characterized in that: the method comprises the following steps:

(1) scanning the maxillary dentition, the mandibular dentition and occlusion records of a patient by using a three-dimensional scanner to obtain digitalized data of the maxillary and mandibular dentitions and occlusion;

(2) importing the dentition and occlusion data obtained in the step (1) into 3D image processing software for model repair, and cutting and flattening the model gum to make the bottom surface flat;

(3) the occlusal surface of the upper jaw is used as a reference jaw surface, and a 3D model of a jaw pad is established in 3D software, wherein the height of the model comprises the cusps of the upper jaw and the lower jaw. Subtracting the overlapping part of the jaw pad and the tooth cusp by using Boolean operation to ensure that the jaw pad has the cusp-fossa relationship of the teeth;

(4) data processing: respectively importing the dentition data in the step (1) and the jaw pad data obtained in the step (3) into 3D image processing software for printing origin setting and related data setting;

(5) respectively printing upper and lower jaw dentitions and jaw cushions by adopting a 3D printer;

(6) and (3) re-curing: placing the printed dentition model into a curing furnace, curing for 25-35min, and correcting the printing model after curing;

(7) combining the maxillary dentition printed in the step (5) with a jaw pad, pressing the jaw pad membrane by adopting a positive pressure hot pressing membrane technology, and if the strength of the jaw pad needs to be enhanced, retaining the 3D printed jaw pad in a pressed membrane;

(8) trimming a positive pressure membrane rear membrane, wrapping the dental crown at the edge of the membrane without pressing the gum;

(9) polishing, cleaning, drying and sterilizing. And (3) acquiring a patient occlusion record by adopting high-precision silicon rubber, alginate or wax in the step (2).

And (3) replacing the posterior teeth with the adjacent teeth when the posterior teeth are missing in the step (2) or the step (4).

And (5) setting the bucco-lingual direction as an X axis, the mesial-distal direction as a Y axis and the maxillo-gingival direction as a Z axis in the printing parameters, and establishing a coordinate system, wherein axial basic units delta X, delta Y and delta Z are set to be 0.25 mm.

In the step (5), polymer materials such as SLA and the like are put into a photocuring forming machine to be used as raw materials, and 3D printing is carried out by adopting DLP or SLA technology; wherein the FDM melting temperature is 80-300 degrees; the printing layering thickness is 0.1-2 mm.

The DLP or SLA ultraviolet light is an ultraviolet LED light source, and the wavelength is 360-450 nm.

The correction in the step (6) includes but is not limited to the correction of errors such as jaw pad edge trimming, flash cutting, leaks, reverse triangles, damaged edges and the like.

And (3) heating time of the film in the dentition pressing film in the step (7) is 1-3 min, and cooling time after positive pressure is 0.5-3 min.

The manufacturing process of the invention comprises the following steps: firstly, acquiring digital 3D data of dentition and occlusion records, designing jaw pad shapes by adopting 3D modeling software, 3D printing (photocuring or melting) tooth models and jaw pad models, then preparing oral functional jaw pads by a hot pressing film technology, and carrying out post-polishing, disinfection and other treatments to obtain the oral functional jaw pads.

The invention adopts a two-step method to prepare the jaw pad. The oral cavity function jaw pad is simplified and manufactured, the method firstly obtains original dentition and rebuilt back jaw pad data according to modes of intraoral direct scanning or impression material conversion and the like, prints a dentition model and a jaw pad model according to dentition 3D data, and carries out hot pressing film on the basis, so that the tooth retention part of the jaw pad is light and thin, has elasticity and is easy to take off and wear. Compared with the whole 3D printing jaw pad, the manufacturing method of the oral function jaw pad can prepare the hard jaw pad with good elasticity, convenient taking and wearing and accurate occlusal surface in a short time. The jaw pad has obvious advantages of low hardness requirement and high elasticity requirement. The jaw pad with high requirements on softness, thickness and accuracy is mainly applied to occlusal jaw pads in the field of orthodontic department, invisible correction, early correction of children and the like.

Drawings

The invention will be described in further detail with reference to the following drawings and detailed description:

FIG. 1 is a flow chart of the present invention

Figures 2 and 3 are schematic views of a functional jaw pad of the present invention

Detailed Description

The invention will be further illustrated with reference to specific embodiments:

example 1

The invention relates to a technology combining 3D printing and hot pressing film, which comprises the following specific steps:

step 1: and scanning the dentition on the patient by using a three-dimensional scanner to obtain the three-dimensional data of the dental arch outside the patient.

Step 2: the occlusion record of a patient is obtained by adopting high-precision silicone rubber, the central line and the positions of the left and right first molar teeth close to the middle buccal apex are recorded, and the obtained occlusion record is scanned by a three-dimensional scanner and converted into digital jaw pad data. To determine the height of the jaw pad required to open the bite and the corresponding jaw position relationship.

And step 3: importing the dental data in the step 1 into Magics software for model repair, flattening the model gum to enable the bottom surface to be flat, and storing and exporting a model STL file;

and (3) repairing the model, wherein the steps comprise but are not limited to trimming jaw pad edges, cutting off burrs, repairing bugs, reverse triangles, damaged edges and the like.

And 4, step 4: data processing: and (3) respectively importing the corrected dentition data in the step (3) and the occlusion recording data in the step (2) into Magics software to perform printing origin and data setting.

The method comprises the steps of respectively importing maxillary dentition model data or mandibular dentition model data and occlusion recording data into Magics software, setting printing platform parameters (length, width and height of a platform) according to a light curing machine, placing the model into the platform, leveling and tightly attaching the bottom plane of the model to the surface of the platform, and storing and exporting a model STL coloring file.

And 5: and importing the model file into an operating system of the printer by using a wireless network or a USB flash disk, and properly placing the position and the interval of the model on the simulation platform. And confirming that the machine state is good and the resin in the material cylinder is sufficient, selecting a proper printing mode (a mode aiming at the dental model), and clicking to start printing to obtain the dentition 3D printing model.

Filling polymer materials such as SLA and the like into a photocuring forming machine to be used as raw materials, and performing 3D printing by adopting an SLA technology; wherein the FDM melt temperature is 100 °; the printing layer thickness is 0.2 mm. The 100 deg. melting temperature ensures a more intimate bond of the PETG to the membrane. SLA ultraviolet light is an ultraviolet LED light source with the wavelength of 400 nm. The SLA technology is conventional and is generally applicable.

Wherein the bucco-lingual direction is the X-axis, the mesial-distal direction is the Y-axis, and the gingival-maxillary direction is the Z-axis in the printing parameters, and a coordinate system is established in which axial basic units DeltaX, DeltaY, and DeltaZ are set to 0.25 mm.

Step 6: after the dentition 3D printing model is printed, the model on the platform is taken down, and the model is cleaned by an ultrasonic cleaning machine with alcohol for 5min and is cured at normal temperature and pressed without deformation.

And confirming that the machine state is good and the resin in the material cylinder is sufficient, selecting a proper printing mode (a mode aiming at the dental model), clicking to start printing, and obtaining the dentition 3D printing model. After the dentition 3D printing model is printed, the model on the platform is taken down, the model is cleaned for 5min by using an ultrasonic cleaning machine filled with alcohol, and the model is dried by using an air compressor (or dried by using paper towels or non-woven fabrics).

And 7: and (3) re-curing: and (4) putting the dried model into a curing furnace, curing for 30min again, and removing the obvious undercut or burr part.

And 8: the maxillary or mandibular dentition model and the jaw pad model are combined, and a positive pressure hot pressing film technology is adopted to press the dentition film (the heating time of the film is 2 minutes, and the cooling time after positive pressure is 1.5 minutes) to be used as a retention device of the jaw pad.

The positive pressure hot pressing membrane technology: a transparent hot-pressed film is formed by heating an acrylic film under vacuum or pressure and then covering the working mold.

The positive pressure hot pressing membrane technology is a conventional technology, and is suitable for meeting the operation requirements in the invention.

Wherein the heating time of the film in the dentition pressing film can be 2min, and the cooling time after positive pressure is 1.5 min.

And step 9: trimming a positive pressure membrane back membrane, and wrapping the clinical dental crown at the edge of the membrane. In the step, the 3D printing dentition model and the membrane are not separated, namely, demoulding treatment is not carried out, and the membrane-dentition whole body is formed.

Step 10: and polishing the prepared jaw pad by a cloth wheel, cleaning by an ultrasonic oscillator, airing, sterilizing by ultraviolet, and packaging. Polishing is a common practice.

According to the invention, after the dentition-jaw pad model is printed, the jaw pad is prepared through the hot pressing film, so that the high hardness of the 3D printing material is exerted, and the requirements of clinical restoration and the like are met. The complicated procedures in the manufacturing process are reduced, the labor cost and the raw material cost are saved, and the possibility of result deviation caused by any error in multiple steps is avoided; meanwhile, due to the high accuracy of 3D printing, the accuracy of the functional jaw pad can be improved, and the clinical requirements can be met. By combining the hot pressing film technology and 3D printing, the oral functional jaw pad which has high elasticity, moderate hardness, good transparency and the like and meets the clinical requirements can be prepared.

Preparing oral function jaw pad based on press mold and 3D printing technique has the shaping fast, low consumptive material, the degree of difficulty low grade advantage, can be used to a plurality of fields such as oral cavity malocclusion deformity is rescued.

Example 2

(1) Scanning the upper dentition of the patient by using a three-dimensional scanner to obtain dentition data, namely three-dimensional data of the upper dental arch outside the body of the patient;

(2) acquiring occlusion records of a patient, recording the central line and the positions of left and right front molars or reserved molars close to the middle buccal apex, and scanning the acquired occlusion records by using a three-dimensional scanner; to determine the height of the jaw pad required when the occlusion is opened and the corresponding bite pad position relationship.

(3) Importing the dental data in the step (1) into Magics software for model repair, flattening the model gum to ensure that the bottom surface of the model gum is flat and stored, and exporting a model STL file;

(4) data processing: respectively importing the corrected dentition data in the step (3) and the occlusion record data in the step (2) into freeform software to design jaw cushions: the occlusal surface of the upper jaw is used as a reference jaw surface, and a 3D model of a jaw pad is established in 3D software, wherein the height of the model comprises the cusps of the upper jaw and the lower jaw. And subtracting the overlapped part of the jaw pad and the tooth cusp by using Boolean operation to ensure that the jaw pad has the cusp-fossa relationship of the teeth, and storing the manufactured jaw pad into stl format for exporting.

(5) Respectively importing the dentition model and the jaw pad model into Magics software for printing origin and data setting;

(6) setting printing parameters, and printing the oral functional jaw pad by SLA or DLP;

filling polymer materials such as SLA and the like into a photocuring forming machine to be used as raw materials, and performing 3D printing by adopting a DLP or SLA technology; wherein the FDM melt temperature is 80 or 120 °; the printing layer thickness is 0.1 or 0.3 mm. The use of a suitable melt temperature ensures a more intimate bond between the PETG and the membrane. DLP is an ultraviolet LED light source with a wavelength of 390 or 410 nm. The DLP technology is conventional and general content is applicable.

(7) And (3) re-curing: placing the printed dentition model naturally dried at normal temperature into a curing furnace, curing for 25 or 35min, correcting the printed dentition model after curing, and removing obvious undercut or burr parts; and the natural drying at normal temperature is to place the printed paper for a certain time without sticking to hands.

(8) Recombining the upper jaw dentition model and the jaw pad, and pressing a dentition diaphragm as a retention device of the jaw pad by adopting a positive pressure hot pressing diaphragm technology; wherein the heating time of the film in the dentition pressing film can be 2min, and the cooling time after positive pressure is 1.5 min.

(9) Trimming a positive pressure membrane rear membrane, wrapping the dental crown at the edge of the membrane without pressing the gum;

(10) polishing, cleaning, drying and sterilizing.

Test No.)

Let us consider the control group otherwise as in example 1, wherein a single hot-pressing film technique was used to make the oral functional jaw pad.

As a result: the produced model has insufficient accuracy and is too thick to be suitable.

Test No. two

Referring to the control group, the rest is as in example 1, wherein a single 3D technique is used to fabricate an oral functional jaw pad.

As a result: the high-hardness membrane is difficult to be taken off and worn and is not suitable for use.

Compared with a single 3D printing technology, the film for wrapping the dental crown part in the invention adopts a film pressing mode, so that the film has better softness and elasticity and is convenient to take off and wear. Compared with a single hot-pressing film technology, the printed occlusal surface is more accurate. Meanwhile, the jaw position relation is directly determined in the mouth, the tooth jaw frame transfer steps are reduced, the clinical operation is simple, and the processing is more accurate.

In the actual jaw pad preparation process, resin modeling needs to be repeatedly adopted, so that the waste cost is high, and the precise form is difficult to obtain. By considering the mature digital 3D scanning and modeling system, the accurate model can be obtained, the digital production in the later period is facilitated, the material cost and the labor cost are reduced, and the modeling precision is improved.

The invention adopts the hot pressing film technology and the 3D printing technology, can prepare the portable functional jaw pad which meets the clinical requirements in a short time, and is called a two-step method for short because the two technologies are adopted and completed step by step. The invention combines the advantages of elasticity, thin thickness and good tooth fitting property of the membrane made by the hot pressing membrane technology and the advantage of high precision of preparing the oral functional jaw pad by 3D printing to prepare the dental jaw pad. The invention overcomes the defects of complicated preparation process, high difficulty, high cost, high hardness and difficulty in meeting clinical requirements of the traditional functional jaw pad, and has the advantages of rapid and direct molding, short manufacturing period, high precision, low cost, small difficulty and the like.

While the foregoing shows and describes the fundamental principles and principal features of the invention, together with the advantages thereof, the foregoing embodiments and description are illustrative only of the principles of the invention, and various changes and modifications can be made therein without departing from the spirit and scope of the invention, which will fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A method for preparing an oral functional jaw pad by combining hot-pressing film and 3D direct printing is characterized in that: the method comprises the following steps:

(1) scanning maxillary dentition, mandibular dentition and occlusion records of a patient by using a three-dimensional scanner to obtain digitalized data of the maxillary and mandibular dentitions and occlusion;

(2) importing the dentition and occlusion data obtained in the step (1) into 3D image processing software for model restoration, and flattening the model gum to make the bottom surface flat;

(3) the occlusal surface of the upper jaw is used as a reference jaw surface, and a 3D model of a jaw pad is established in 3D software, wherein the height of the model comprises the cusps of the upper jaw and the lower jaw. Subtracting the overlapping part of the jaw pad and the tooth cusp by using Boolean operation to ensure that the jaw pad has the cusp relation of the teeth;

(6) and (3) re-curing: placing the printed dentition model into a curing furnace, curing for 25-35min, and correcting the printed model after curing;

(9) polishing, cleaning, drying and sterilizing.

2. A method of preparing an oral functional maxillopad incorporating heat pressed film and 3D direct printing as claimed in claim 1, wherein: in the step (1), the occlusion record of the patient is obtained by alginate, silicon rubber, wax or oral cavity scanning.

3. A method of preparing an oral functional maxillopad incorporating heat pressed film and 3D direct printing as claimed in claim 1, wherein: when the back teeth are missing, the adjacent teeth can be used for replacing, and the tooth replacing gap can be reserved to reduce the influence of the jaw cushion on the tooth eruption to the maximum extent.

4. A method of preparing an oral functional maxillopad incorporating heat pressed film and 3D direct printing as claimed in claim 1, wherein: the 3D printer adopts DLP or SLA ultraviolet light, and is provided by an ultraviolet LED light source, and the wavelength is 360-450 nm.

5. A method of preparing an oral functional maxillopad incorporating hot-pressed film and 3D direct printing according to claim 1 or 4, wherein: the FDM melting temperature in the step (5) is 80-300 ℃; the printing layering thickness is 0.1-2 mm.

6. A method of preparing an oral functional maxillopad incorporating heat pressed film and 3D direct printing as claimed in claim 1, wherein: and (5) setting the bucco-lingual direction as an X axis, the mesial-distal direction as a Y axis and the maxillo-gingival direction as a Z axis in the printing parameters, and establishing a coordinate system, wherein axial basic units delta X, delta Y and delta Z are set to be 0.25 mm.

7. A method of preparing an oral functional maxillopad incorporating heat pressed film and 3D direct printing as claimed in claim 1, wherein: and (3) heating time of the film in the dentition pressing film in the step (7) is 1-3 min, and cooling time after positive pressure is 0.5-3 min.