The clash of the titans are in full effect. We are not smart enough to understand all the dynamics of patented software and hardware. While we let the manufacturers sort it out, we wanted to demonstrate how the new mandibular jaw movements are captured in Meditlink
Many scanners limit the number of scans you can take on a patient. This becomes cumbersome when you want to image pre-existing conditions, tissue scans for implantology, and other advanced needs
With version 3.0 in Meditlink software, launched in October of 2022, you can import or scan multiple models in the same patient chart
We’ve digitized the Vita 3D shade guide to help with color identification. The same Medit scanner was used to scan the tabs and then this digital file was created. the assumption is that the same camera and light will hit natural dentition and the net effect will be the same. Use at your own risk.
To use the Artificial Implant Suprastructure Identification Software to identify a scanbody, you have to understand how it is listed in the library. It is not listed by the name of the implant company but rather the manufacturer that fabricates that implant lines scanbody. For example, there are multiple choices for Nobel Active Conical Connection scanbodies. The easiest way to find them is to search for the pre-loaded brands, but be aware of the routing abbreviations many companies utilize. For Nobel Active, usually NB AC is used.
Then you must choose whether you are going to fabricate a Ti-Base or a Custom Abutment, and whether you are using an intra-oral or extra oral scanbody. The connection type (diameter) and the material (titanium vs. chrome cobalt) also must be selected. Here’s a quick video that illustrates the selection process. You must also consider if a 10 or 14 mm diameter blank is going to be used to mill the product. In molar areas, a size 14 is preferred so that you can reach the outer most boundaries of your desired margins, whereas a 10 mm blank may be too narrow and small for a molar.
For more detailed videos visit the Implantology Section of our Online Tutorials
A fracture and worn overdenture greater than 10 years old was duplicated digitally where the lab was able to follow the vertical dimension and tooth position from digital impressions taken by the Medit i500. Clinically, we advise that you place the housings before taking the impressions to accommodate enough space for the chairside reline. In this particular case, most of the reline and imaging was done extra-orally
We have an MO a DO on adjacent teeth that need to be done and a crown in between. It took only 90 minutes to do all 3. I prepped the crown and got that milling and while it was milling I restored the adjacent teeth. I then tried the crown in. what’s great about lithium disilicate vs zirconia chairside is that I can easily add a contact on with powder while its crystalizing. or I can adjust the composites to nail the contacts. so we leverage mill time and oven time with prep time. Said another way, it takes me the exact same amount of time to do a crown + 2 class two’s as it does to do a single crown
One of the most important lessons a digital dentist has to learn quickly is how to not introduce errors when scanning dentition. The most likely area when s/he can introduce errors is in the anterior area where the incisor are not only narrower than molars but can also have translucent enamel. Add just a little spacing between teeth with diastemas and you can quickly distort the accuracy of the model. This is true of ALL intra-oral scanners in the market
There are a few ways you can overcome these issues and the second video highlights some of our preferred methods. The concept is easy- block the light from travelling through the tooth structure and you are set! Watch the videos to learn how to do itHere are some examples of how light shinning through the enamel and /or ceramic instead of bouncing back resulting in errors in model accuracy. Lesson #1 for every ios user is to know when and where they are likely to introduce error. in dentate cases, it usually is right that the transition from premolar to canine to lateral. The surface area decreases dramatically and if you have translucent enamel and / or material and / or highly reflective surfaces you can “derail” the model building. Here is an exaggerated demonstration
Translucent enamel can also play a role in distorting the cavosurface margins of a inlay or onlay restoration. When imaging from the occlusal, the gingiva below the margins acts as a barrier to block light transmission through the enamel, but as soon as you start to roll the camera to the buccal or lingual, and you have enamel with no substrate behind it to block light transmission, you can introduce errors in the equation with any scanner.
There are many ways to combat this which include powdering the tooth structure, using a rubber dam, or in Medit’s case, you can use the color subtraction filter. You selectively tell the scanner to ignore certain colors and you use that exact color (here, it is the color of the glove) to block light transmission through the enamel. So the software just ignores the blue, but the light is prevented from shining through reducing the errors you would introduce.
Here is another example of the distorted enamel margins on a conservative preparation and how blocking out the light from travelling through the tooth structure leads to crisp visualization of margins without any distortion or artifact
For advanced users of meditlink software, you can skip filling out the Rx form and go straight into scanning. But make sure to properly fill out the CAD Rx form so that all the necessary models are imported into the design software. If you don’t designate the opposing or the Pre-op / Wax-Up in the form, they will not be part of the design equation. Also, this video shows how to select multiple restorations at once.
in this case we import multiple models, videos, CT scans, and Face Scans so that our users can utilize all of these features. Click here to enter the member’s section to download the whole case and design along
here is a list of why the Medit Artificial Intelligent Implant Suprastructure Identification System is significantly more advantageous over all other cadcam systems.
With Medit’s Crown Fit function, you can see exactly how much cement is required to seat the restoration and how well it is adapted to the tibase.
This article features the new Meditlink 2.3 software which has some advanced functionality. One of the greatest achievements is he ability to tell the scanner to avoid imaging certain colors like green and blue. This greatly facilitates the imaging of full arches as you can let your gloves / fingers guide the camera and displace all the soft tissue that impedes image capturing. We also feature how easy it is to launch CAD software to design the restoration and mill it out of lithium disilicate material
Case set up: here we enter the patients name and a simple tab appears where we chose the material and restoration tab. Once you image, you can place an order to the lab or you can advance to the CAD tab:
After the Rx has been filled out, you can launch the Medit Scan and image the upper and lower arches. Please note how we tell the camera to avoid the color blue and it ignores the clinicians fingers during imaging. The upper jaw and lower jaw were captured, then the bite registration even before the preparation was finished. This allows the verification of proper reduction and space for the ceramic material
Lower Arch Scan
The lower arch is the most difficult area to scan as you frequently have to battle the tongue, saliva, and the lips. The optragate can be of great help but notice how we use the color filter to hide the blue gloves while we advance the camera. It is a great aid in facilitating the capture of the lower arch
Upper Arch Scan
The same principle is applied to the upper arch. Notice that the software does not care if you start with the upper or lower arch. Here, you can visualize how the blue glove was used to displace the cheek and capture the pre-op condition of the upper second molar. The rest of the arch was easily imaged. It is not necessary to capture full arch impressions and this was done just for demonstration purposes. For a single unit case, generally imaging distal from the canine is adequate.
Checkingthe reduction and aquiiring the bite registration
We recommend that you capture the bite before you finish imaging the preparation. This gives you one last chance to verify that you have reduced enough to accommodate material thickness. You can see how we just take regular photos to document the lack of clearance and we continue to adjust the height of the preparation until we achieve the required space. We then activate the imaging process and capture the occlusal relationship between the upper jaw and the lower jaw
Image the preparation and place margin in native MeditScan Software that transfers to CAD Software
The preop condition is then transferred to the arch model and the tooth in question is cropped out. The rest of the arch is protected so no extra data is added unnecessarily to the equation. This protect feature is used for demonstration purposes and is subsequently removed. The prep in question is then highlighted and the local area is processed and the margins are placed. This margin line can be sent to the lab or it can be automatically carried to the design software
Launch CAD Software
The Meditlink software allow you to launch a variety of CAD programs that include 3shape, exocad, cerec, etc… Here we launch exocad which automatically imports and aligns the models and marks the margins. The restoration is then designed to completion.
Design of restoration
The CAD software allows you or the lab to alter the marked margins if necessary. The restoration is aligned in the arch for and the contacts are adapted to the adjacents and the oppising
You can take the designed restoration to ANY milling machine or printer
Milling of Lithium Disilicate with Imes Icore Coritec One
The final restoration design can be exported as an stl and taken to a variety of mills or printers. Here we designed it millbox and milled with the coritec One. The material used was Amber Mill and it was crystalized and seated
Post-op X-ray
Final X-ray was taken to verify the fit and to make sure no excess resin was left behind
The following pictures depict the sequence of burs we recommend that you use to finish a preparation quickly. While patient is getting numb, take a quick look at the clearance you will need to reach proper material thickness. Once the quadrant is isolated with isolite and optragate, take an occlusal router bur and create a trough to gain the proper depth. Follow that with a flat disk, and you can quickly reduce the occlusal height.
A shoulder bur of .8 mm thickness can help you reduce the interproximal areas as well as the buccal and lingual margin lines. Before finishing the prep, place hemostatic agent like expasyl in the sulcus and place retraction cord. while it is setting, check your reduction. If you need more space, now is the time to reduce some more.
Once you have adequate clearance, retraction, and hemostatis, you can readily image and find your margins in the CAD software
A Medit i500 scan was taken and merged with a CT scan and the distance to bone was measured (5.5 mm’s) giving enough space for soft tissue contouring with a diode laser. The 3D X-ray must be captured with cotton rolls placed in the vestibule so that you can differentiate between the gingiva and the lip. Ideally you should not close the base of the digital model by the intra-oral scanner as it can make the merge of the data sets more difficult than it needs to be.
Comparison of Pre-Op Scan and Post Gingivectomy Scan with Medit i500
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