Intraoral scanning in dentistry

Common mistakes in dental intra-oral scanning and how to avoid them 

3d scanning is becoming more widespread in dentistry. Digital scans of teeth replace traditional plaster models in most processes, from prosthetic to the orthodontic procedures. Broadly speaking, dental 3d scanning is done in two ways: 

• Scanning a physical model, originally obtained from impressions, using a desktop scanner; or

• Scanning intra-orally directly 

This paper will focus on the method of intra-oral 3d scanning and some of the most common mistakes associated with this solution.

How do intra-oral scanners work? 

Intraoral scanners are devices for capturing direct optical impressions in dentistry. They project a light source (laser, or structured light) onto the scanned object, in this case dental arches. The images of the dentogingival tissues captured by imaging sensors are processed by the scanning software, which generates point clouds.

This technology allows creating highly accurate representations of the patient’s dentition that can be used for a wide range of purposes, including smile design. 

Benefits of intra-oral scanning 

1. Precision. Combined with CAD/CAM planning softwares and services, well-tailored individual dental appliances can be produced, ensuring the best results in prosthetics, surgery, orthodontics, etc

2. Real time quality feedback. Dental impressions can be examined instantaneously lowering the risks of having to retake an impression after the patient has already left the office.

3. Speed of the process. Digital models can be uploaded to the laboratory interface in a few seconds, saving precious shipping days.

4. Selling tool. IO scanner can be an effective communication tool with today’s digitally-oriented patients. 

Disadvantages of intra-oral scanners 

1. Cost. Although prices recently tend to decrease due to escalating competition, most intra-oral scanners are priced between USD 15-50,000 

2. Learning curve. As with every new technology, some time is needed before the scanning technique can be mastered sufficiently. 

Common IO Scanning Mistakes and how to avoid them 

High-quality dental scans or impressions are critical for the orthodontic treatment process.

Examples of low-quality scans

Scanning was done too quickly and software could not assemble the surfaces correctly:

An incomplete scan of the lingual area results in missing surfaces:

Incomplete lingual scans causes software to create incorrect surfaces:

A high-quality scan should include:  

1. The entire arch including the terminal molars;

2.  All incisal edges and marginal ridges; 

3. Complete occlusal surfaces (no holes); 

4. Interproximal embrasures, IPR and natural interproximal spaces; 

5. Clear gingival margin with 3-5 mm of lingual and buccal gingivae; 

6. Left and right bite scans covering at least 3-5 teeth to ensure proper occlusion. 

7. No defects, holes, artifacts, bumps or tunnels

Examples of high-quality scans

General eXceed requirements for the scans

• STL format only 

• Both arches should be captured, even when only a single arch treatment is requested. 

• Both arches must be scanned and positioned in occlusion. 

• Each arch saved as a separate STL file. 

• A single arch file must contain between 100, 000 and up to 300 000 triangles. 

• Typically, the single arch STL file size will be between 3 Mb to 15 Mb in size 

Get Started with eXceed 

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4. Our Support Team will generate the account;

5. Schedule a remote session to submit first case.