WO2017115154A1

WO2017115154A1 - Three dimensional smile design

Info

Publication number: WO2017115154A1
Application number: PCT/IB2016/050003
Authority: WO
Inventors: Ahmed Abdelrahman; Rami GAMIL
Original assignee: Ahmed Abdelrahman
Priority date: 2016-01-01
Filing date: 2016-01-01
Publication date: 2017-07-06

Abstract

Method for designing the smile in three dimensions, the method comprising: taking a three dimensional facial scan; taking an intra oral scan for the teeth; taking a cone beam computerised tomography (CBCT) Scan of the face bones; aligning the extra oral scans and the intra oral scans together; drawing the design using three dimensional lines and planes; exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with dental software.

Description

(1) Title of invention

Three dimensional smile design

(2) Technical Field

This invention relates to Dentistry and Smile Designing.

3) Background Art

In the past years facial guided smile design was the used tool to design teeth to fit the patient's face according to smile design principles in the literature.

For a long time clinicians and researchers have been using drawn sketches on patient's photos to design the shape and position of teeth that match patient's face. Some researchers and clinicians started using computer softwares like Adobe photoshop, Microsoft powerpoint or Keynote to draw lines and frames that determine the best position of the teeth to get a good and attractive smile that fits each face using two dimensional photos on those softwares and draw the design on different photos with different views to get a final imagination for the three dimensions of each tooth.

With the revolution of using computer-aided design and computer-aided manufacturing (Cad \Cam ) softwares and fabricating the dental restorations using those three dimensional (3D) softwares the two dimensional (2D) design was used as a visual guide for the 3D designer who works on CadVCam software to design teeth in similar dimensions, shape and position of teeth designed on 2D photos.

Many companies started to launch smile design softwares to help dentists to do the 2D design more quickly and efficiently they also tried to make it easier to transfer this 2D design to Cad/ Cam software by locking the 2D drawing of teeth on the computer screen and using them after starting CadVCam software trying to fit the 3D design into the 2D locked design on the screen.

(4) Summary of Invention

[Technical Problem ]

After many trials clinicians and researchers discovered that it is impossible to transfer a 2D design into 3D space accurately which depends a lot on the skills of the of the 2D designer to make a realistic design that can fit the face in reality and also on the skills of the 3D designer who should simulate this design in 3D and a lot of guessing is used in this procedure.

Besides, softwares that used screen locked 2D design to fit with the 3D design were not realistic because of the distortion between different 2D views trying to use them in 3D software. Also, this locked design is not scaled to the 3D model of the teeth so in case of zooming the model or rotating it in 3D the 2D design doesn't neither zooms nor rotates with the model but it remains fixed under the same magnification and at the same angle which makes it impossible to reproduce this design accurately in reality. [Solution of the Problem ]

Since the aim is to create 3D structure of teeth the solution of the problem is to design the smile in three dimensions from the beginning rather than designing in 2D and transferring into to 3D with all inaccuracies resulting from this transfer.

(5) Detailed Description

In order to eliminate the inaccuracies of transferring the design from 2D to 3D we have to design the smile and draw the lines , frames and meshes of the design in 3D space in the first place.

The challenges we faced and the solutions to solve them were as follows :

1- To have a 3D photo for the face so we can design the smile according to the rest of the face (facially guided ). In order to solve this we used three dimensional face scanner called proface stereophotogrametry or stereo camera based with cone beam computerised tomography (CBCT) or any low dose x-ray imaging modality to get the face of the patient in three dimensions integrated with the jaws bones.

2- To have an accurate scan of the teeth since the facial scanners and CBCT cannot reproduce an accurate scan for the teeth to design in accurate measurements. To solve this we used intra oral scanner that produces an accurate three dimensional scan for teeth using reference points in the facial scans and CBCT to stitch the intra oral scans to the extra oral scans .

3- Drawing 3D lines of the design attached to the 3D scan of the face. In order to solve this we exported face,bone and teeth scans in STL file format or any 3D file format to open-source 3D computer graphic software (Blender) putting all design lines in 3D on the face and teeth. Those lines represent :

1 - Horizontal plane of the face (inter pupillary line)

2- Facial mid plane

3 - Smile curve according to the curvature of the lower lip

4- Width proportion for the teeth

5- Gingival margin of each tooth

Following that we used this design to create a 3D mesh for each tooth that determines the exact three dimensions form and position for each tooth.

After doing this we have a ready 3D design for each tooth but to get use of it we had to export this exact design to Cad/Cam dental software which can fabricate a restoration according to our facial guided design. We exported the teeth scan with the designed mesh together as STL file format to a Cad/Cam software so we can see the mesh we designed locked with the teeth model on Cad/Cam software very clearly determining the exact position and form for each tooth.

Cad/Cam Software was used to fill this mesh with the restoration and by doing that we had the exact and distortion free design ready for printing or milling with accuracy, predictability, and repeatability of the procedure.

Claims

1. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with dental Cad/Cam software to fabricate dental restorations.

2. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with orthodontic softwares.

3. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with smile design softwares.

4. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with dental implant planning softwares.

5. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in any 3D file format compatible with dental softwares .

6. A method for designing the smile in three dimensions, the method comprising: taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

7. A method for designing the smile in three dimensions, the method comprising:

taking a three dimensional facial scan;

taking an intra oral scan for the teeth;

taking a cone beam computerised tomography (CBCT) Scan of the face bones;

aligning the extra oral scans and the intra oral scans together;

drawing the design using three dimensional lines and planes;

exporting the three dimensional lines attached to the intra oral model in STL file format; and using the three dimensional lines planes attached to the model with 3D printing softwares.