Sunday, May 19

What are digital dental impressions?

They are direct impressions in the mouth by means of a digital intraoral camera, leaving the data obtained in a computer with an image management program for the design and preparation of digital models.

Impressions can be full arch, half arch, individual teeth, or both arches.

There are different techniques: laser photogrammetry, structured light (blue or white LED light), 3D video.

Photogrammetry:

By means of a scanner, we take a series of overlapping photos, having a series of anatomical structures as a reference point. Photographs are taken that are digitally assembled and a 3D model is made.

To be:

Itero. It is a laser beam that is reflected on the surface, and through a sensor, we obtain a 3D image.

Structured light:

Cerec Blue Cam.  There are 2 beams of light that are emitted, and the reflection of this light allows us to measure the angle, and when we have the angle and a bunch of points (in bands) it allows us to know the depths. It works like the Face ID sensor on the iPhone X, but with two light beams instead of 20,000. The height recognition technique is carried out by means of calculations with the Pythagorean theorem. You have to put powder on the tooth surface.

3D video:

Wash COS. It works by video: the images are superimposed, obtaining a 3D image. It works more or less the same as structured light, but without the need to use powder.

Dusty optical impressions:

The powder is used to determine height with an automatic triangulation system using overlapping photographs. It requires that it does not have reflections, and the reflection of the light must be total. Titanium oxide is used as a powder. The powder is used to avoid reflections when taking the impression, and thus avoid defects.

Dust-free optical impressions:

3D video cameras are used that cover the real dental surfaces of the patient and mount the model by superimposing images on a computer.

The Palate Is Not Registered In Any Of The Techniques.

Digital printing systems:

Digital impression taking systems are:

Cerec:  blue cam (with dust, uses blue light, details up to 25 microns) and Omnicom (without dust, it is used more).

itero:  uses a parallel approach that uses an optical or laser scanner to digitally capture tooth and gingival surfaces and contours. Do not use powder.

Trios:  does not use powder, uses combined optical and laser light. You get a lot of detail.

Lava:  is a 3D imaging system.

E4D:  is a laser imaging system. It is not used in Europe, but it is in the US.

Carestrean: intraoral camera for capturing high-speed 3D images. It is cheaper, it is used in the preparation of veneers.

Digitized or CAD-CAM models are made by intraoral digitizing or through a standard impression. There are in vitro studies that show greater accuracy with optical scanner digitization from a previous impression of the abutment tooth and obtaining a master model.

digital model:

They are used to plan treatment on the computer. They can be seen on the screen, or they can be CAD-CAM: subtractive techniques (they take a piece of material and mold it) or additive techniques (3D printers or laser sintering). They are used in the clinic or in the laboratory. Various materials can be used: resins, metals, etc.

3D printers are very versatile, they allow you to do everything, they achieve perfect accuracy