Most if not all milling machines do not adequately cool the tools or restoration while milling. At CAD-Ray we have developed augmenting tools that reduce or eliminate any dry milling of glass ceramic restorations. We can either run tubing from the holding tank or we can submerge the block for soaked milling
This implant was initially placed at the crest of the ridge in 2012. its placement did not allow proper emergence profile and subsequently lost bone around the head of the implant by 2015. The lack of blood flow to the crest of the bone at the cortical plate certainly could have contributed to its demise. By 2015, the bacteria trap forced a new restoration to be placed which also ultimately lead to chronic inflammation due to improper contours. The implant itself was well integrated and the decision was made to remove the top 3-5 mm of the implant and treat it as a cast post and core.
You can see how the Medit i700 was used to mix intra-oral scans with a PVS impression to capture the fixture. Advanced users can utilize the stl of the implant itself to fabricate a post and core digitally.
The designed restoration was then sent to Burbank Dental Lab and it was milled out of wax and then cast to metal
The post and core and the emax restoration were returned for delivery. The emax was not crystalized until after the abutment was cemented and then it was tried in by itself to assure proper contours and contacts. The great feature of lithium dissilicate is that you can add contact and glaze at the same time, which was required here as the mesial contact was weaker than desired after some minor adjustments
Post op x-rays to verify seat and no excess resin after flap was raised to clinically visualize that there is no excess cement
For our advanced users who mill in house or what to speed up their digital impressions we advocate taking advantage of digital dentistry’s unique features that allow you to take impressions over a period of time and segments, building larger models over different sequences and time. In this particular case we have two molars in the lower left quadrant that warranted replacement. The traditional method would be to prep both, isolate both, retract both, and take your final impression, but we will approach this as if there are two separate patients involved
For the second molar, we will take advantage of the anesthesia time and capture the first bite, the opposing, the pre-existing situation and then crop out the preparation area digitally. Once the tooth is prepared, we will check for proper reduction. We will then take the second bite to verify the vertical dimension has not changed.
While the second molar is being designed and milled in the first case, we will launch a second window by cloning the first case. All the data remains the same and this time we crop out the first molar digitally and protect the rest of the arch. Once the first molar is isolated, it is digitally captured and then designed and milled.
To manage the contact between the two crowns, there are many advanced applications. Here is a simple explanation of how we use the prep model from case 1 as the pre-op model for case two. Since the second molar in case 1 made contact with the distal wall of the first molar, when we design the crown for the first molar in case 2, all we have to do is make sure the distal wall is flush to the pre-op. This guarantees us a contact between the two. There are lots of shortcuts to this puzzle once you get the basics of digital impressions under your belt.
We quickly printed these same models and crowns just for demonstration purposes
For our coritec users: new users often mislabel restorations in the Rx form that leads to a lot of trouble. like calling a crown and onlay or vice versa. this can lead to all kinds of trouble
first sign of trouble is if the two purple lines don’t define the borders of the the restoration. sometimes it is missing, other times it is off the restoration. so always double check this step and usually the missed nomenclature is what causes the trouble.
the next problem people have is that the default setting for the sprue design is poor. it makes the sprue thicker at the mandrel than the restoration. this creates a crevice that the drill can’t get to. this leads to quick drill breakage as it tries to drill into that space (red circle). it is easy to set change these settings so the drill “flows” with the design of the sprue and you get a lot of use out of it. it’s annoying to do this manually so a subsequent video shows you how to change this by default.
another problem is the offset. the last video shows the distance from the restoration to the mandrel as 2mm. the drill is 2.5 in diameter. if you set it at 2, the calculation doesn’t allow enough space for the drill that also breaks it off. set it at 2.7 or 3 and it will last you a long time.
two subsequent videos will show you how to create your own blocks and change their orientation, so you can fit a taller design into a smaller size block
DISTINCT ADVANTAGES OF DIGITAL IMPRESSIONS
Here are two very simple examples of clinical advantages of digital impressions over analog ones. You can edit or add to your models and you can work independent of time and sequence.
You can also know immediately if you have captured your margins correctly. Once you understand these concepts, there are dozens of ways you can apply these principles to make some of the most challenging clinical cases very easy to manage
FIND OUT HOW RESTORING IMPLANTS CAN BE THE MOST PREDICTABLE PROCEDURE YOU CAN DO
For decades, placing and restoring implants was a very stressful and unpredictable procedure. Digital dentistry has reversed that trend, making it now the most predictable procedure you can perform. You can easily capture contacts, opposing dentition, and the location of the implant. More importantly, you can design the emergence profile to your liking.
SEE HOW EASY IT IS TO ADD A CONTACT TO A RESTORATION WITH AN OVEN
Emax restorations are milled in a pre-crystalized state (blue phase) as it is more gentle on the drills than the final crystallized form. A big advantage of emax lithium dissilicate material is that you can easily add contacts with addition powder in the same cycle as glazing. This reduces the stress of try-ins and allows you to recover without wasting precious time. Other materials on the other hand may require extensive oven times or a re-mill (or send the restoration back to the lab)
In Digital Dentistry, once you acquire your models accurately, the CAD software doesn’t care where and how you capture them. Once you are done with the design, the cam and the milling machine have no clue what scanner you used.
here we take an intra-oral scan with the medit i500 and design in exocad and send it to 2 different milling machines. One is the CEREC MCXL and the other is the imes icore coritec one.
we even milled the bridge with the z4 milling machine by vhf just to show the concept works
Please Note: This page is from dentalcadcamshop.com: 13.03.2020
When it comes to single visit dentistry (procedures in under 90 minutes), CEREC is tough to beat. From the integrated camera, CAD software and mill, CEREC is the most streamlined technology to serve patients in one visit.
Nevertheless, increasingly doctors are expanding their range of indications with CAD/CAM technologies and sometimes we simply want to combine CEREC with other equipment and software manufacturers. But wait, isn’t CEREC a closed system? Yes and no. While nobody would accuse CEREC of being a completely open system, it is possible to export .STL files of CEREC scans which gives us some flexibility to bring CEREC scans into other programs.
But today we are not focusing on exporting CEREC scans, but rather:
1) How can we bring scans from other cameras into CEREC?
Example: I own a 3rd Party Camera and I want to import those scans into CEREC for making crowns, etc.
2) How can we use CEREC to mill CAD objects made from 3rd Party Software?
Example: I own a 3rd Party CAD Software and want to import those into CEREC for milling.
But wait, I thought no 3rd Party files (scans or CAD designs) may be imported into CEREC. How, then, can we unlock the system? The missing piece to the puzzle is the inLab Software! With inLab Software, the CEREC system can be opened up for all kinds of interesting workflows. Here are two workflows CEREC owners constantly ask us about:
1) I own a 3rd Party Camera – How do I mill from my MC XL?
2) I own a 3rd Party CAD Software (e.g. exocad) and I want to mill (e.g. crowns) designed with 3rd Party software and mill them with my MC XL
Please note carefully the Requirements listed above!
– If you want to import a Scan .STL… You will need the inLab SW Interfaces Module, inLab CAD Software (18.0 and above) andthe inLab CAM Software (18.0 and above).
– If you want to import CAD .STL designs for milling… You only need inLab CAM Software (18.0 and above).
– In case you never owned any inLab Software before, or your copy of inLab Software is below 4.X, you will additionally need to order the License Stick (SKU: 6364785) and install the License Stick on the PC or workstation on which you are using the inLab Software (CAD or CAM). Please note this is NOT the same License Stick as you have on your CEREC AC unit!
– In no case can the inLab Software mill on the CEREC MC!
Still have questions? No problem, we are here with answers: Contact us
Good luck everyone and Happy Milling!
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In this clinical case a patient lost a pre-existing crown. The remaining tooth structure had recurrent decay and a new crown was warranted.
After anesthesia was administered, the clearance from opposing dentition was assessed. The preparation was reduced to accommodate the necessary thickness of the material.
Once adequate clearance was achieved an Optragate was placed and an isolite was used to isolate the area. The preparation was scanned and then the lower arch was captured. The buccal bite was then taken to along the arches together
With Meditlink software, you have the option of designing the case yourself or sending it off to your partnered lab. The following video shows what happens to your case once the lab downloads the case
In this particular case, we designed our own crown and milled it with the coritec one milling machine
Once the amber lithium disilicate material was milled, its for was verified clinically. The crown was then crystallized and seated with NX3 resin cement
In this case presentation, we utilize the medit i500 to image the pre-existing crown and to fabricate a restoration that is a replica of the pre-existing condition. The patient was advised that the recurrent decay was in close proximity to the canal space and that endodontic treatment may be a possibility. The CBCT showed no evidence of any peri-apical radiolucency and the premolar tested vital prior to treatment
Case set up involved imaging the pre-existing condition in the pre-op catalog box. Excess information was cropped to reduce file size. The data was then copied to the maxillary arch catalog box and the area to prepared was edited out in preparation for final optical impressions.
Immediate Post Op
The remaining decay and previous build up material was removed just prior to bonding the restoration with NX3 dual cure resin cement so the dentin was exposed for the least amount of time possible.
In this article, we demonstrate how to manage a crown replacement on a second upper premolar with the Medit i500, exocad, and the imes icore CORiTEC ONE milling machine. The pre-existing crown was over 2 decades old and the recession revealed a supra-gingival margin. Furthermore, there was no room to improve the anatomy or its outline form as it was in occlusion with the opposing dentition.
A powerful design technique is the copy of the pre-existing crown. Images of the pre-op are taken while the patient is numb and its contours are copied onto the final design of the restoration. This process usually takes a minute or so, after which we milled a size 12 emax block restoration.
One of the most dreaded procedures in dentistry is to cut off a bonded lithium disilicate material. With zirconia, since the bond strength is weak, just “rattling” the crown helps it pop off. You could also debond the restoration with a laser pretty quickly. With emax, you must use copious amounts of water so you don’t fry the pulp. You must also refrain from splitting the crown with a crown remover because you can damage the remaining tooth structure catastrophically.
In this sequence of photos, you will see how we recommend the removal of the bonded restoration. You must first create a trough across the occlusal surface of the crown. Ideally, use a 1.6 mm disposable bur to reach the interface between tooth structure and restorative material. As soon as you reach this junction, take a flat ended diamond bur and start working that same location and remove all the ceramic on the occlusal surface. Staying right at the junction of the material and tooth is the critical part of the process.
After you have removed the occlusal surface, you can take any bur and work the junction one the axial wall. By this time enough work has been done where the walls of the restoration start to break and peel off on their own.
All milling machines have guidelines for proper cleaning and maintanance. The imes icore CORITEC ONE’s spray channels must be kept clean, otherwise they will spray off the target block materials. Essentially you will dry mill ceramic which will damage the material and break the drills very quickly.
You can see how little particles of ceramic and titanium dust can clog the lines.
Here we just used an ortho plier and orthowires to unclog the lines. It’s easiest to have the water spraying so you can identify the channels and see the immediate results.
When cleaned and clear make sure the water it sprayed on tip of the drill from all channels.
A new feature coming to Medit i500 is the automatic detection of scanbodies while you are imaging. In this clinical case, two implants are placed in the lower left quadrant in a fully guided fashion. Spacing limitations and proximity to vital anatomy did not allow for proper parallelism. This can create all kinds of headaches with analog dentistry where the trays can inadvertently lock in the mouth of distort upon poor up.
With the digital approach, you can scan the gingiva, the arch with easy access to adjacent contacts, and then the scanbodies themselves. What is great is that you do not disturb the primary stability you just achieved by placing physical forces on freshly placed implants.
Once the images are captured and the scanbodies are identified, we launch exocad and the data is not only automatically imported into the Computer Aided Design Software, it also plots the fixtures in the correct position and identifies their location and timing so you can proceed with the design of the custom abutment and / or tibase restoration.
This 4 unit case was imaged in Medit i500 and designed in exocad. The final restoration was taken to CEREC inlab cam. When the construction file is imported into cam, it contains data such as the margin line which is important for the milling machine to know for its tool path calculations.
In this particular situation, the construction file dictated the position of the restoration in the block which would have not allowed for proper milling. Instead of loading the construction file, we imported the stl design, redrew the margins really quickly and were able to mill the two separate (4 unit) case out of a single emax block.
The milled restorations were then separated and finished free-hand
try in and deliver of 3 unit bridge and single unit veneer after extraction of right central incisor
try in and delivery of a 3 unit bridge and a single unit veneer
In this article, we feature an upper left lateral crown that needed to be replaced due to recurrent decay. While the patient was getting numb, we defined the job description in the Medit i500 software and imaged the pre-existing crown, the opposing and the bite. We digitally cropped out the tooth to be prepared and proceeded with crown removal. Once the margins were refined and the tissue was displaced, we imaged the preparation in HD mode and processed the case.
Once the digital models were rendered, we launched the integrated CAD software that automatically imported the pre-op, the opposing, the prep model, and the bite. Their relationship is preserved in the CAD software and no modifications were necessary. You have two ways to copy the pre-op; one way is to program the CAD software so it replicates the pre-op perfectly while the other gives you a raw proposal that you can then choose to adapt to pre-existing situation.
Once the case is designed in the CAD software, you can then take it to any CAM and Milling Machine to produce a restoration. Here we milled an emax restoration with the CEREC MCXL and the imes icore CORiTEC ONE at the same time so we can compare the final results. The CEREC milling machine produced a restoration faster by about 90 seconds but the final results of the margins by the CORiTEC Machine was far superior. Also, the CAM software, Millbox in this situation, allows us to choose a third drill that is 0.6 mm in diameter. This increases milling time but results in less overmilling than the 1.2 mm burrs that milll the intaglio of the CEREC Machine.
Immediate post op
Please, take a seat, you should not be standing while you watch this.
Artificial intelligence by Medit i500 now identifies the location of your scanbody but it also automatically launches all that proper information into CAD software for instant abutment designs. Make sure to watch both videos. Enjoy.
A custom titanium metal abutment is milled in such a manner where the drills DO NOT touch the connection. The type of connection is predetermined by the blank manufacturer and the cylindrical part of the abutment is milled out. This makes the symmetric geometry of the abutment a bit tricky for some to handle as indexing it properly to manage the timing of the connection is critical for easy delivery.
It is a good idea to know the exact dimension of the screw access hole. You want to set the diameter just outside the channel so that you don’t have to do a lot of post production adjustments. if it is made too thin however, you can have a mis-mill and have to repeat it. We’ve found 2.5 mm the perfect setting for the DESS titanium abutments.
Download this case to mill and see the results for yourself
At CAD-Ray, we are constantly looking for solutions that will satisfy a clinician’s needs in a dental practice. For the better part of a full year, we have been developing milling strategies that can speed up the manufacturing process and increase the longevity of the drills and the instruments used in fabrication.
In this video, we demonstrate a sample crown milling simulation where we try and place the restoration in the block to render the fastest crown in the shortest amount of time possible, with little wear on the drills.
Milling Simulation
The new Medit i500 software will feature the ability to mark margins in the imaging step before you import the case into a CAD software or send it to the lab. In this article we showcase a case where a 12 year old implant crown needed replacement. The pre-op images were captured, along with the opposing and the bite.
After the area was anesthetized and the crown was removed, expasyl was used to achieve hemostasis and tissue retraction. The margins of the abutment were imaged. Note how we used a feature in the Medit scanner to change the scan light from blue to white, which allows you to pick up red (blood and tissue) that is normally difficult to capture.
Once the margins were captured, we activated the margination tool. You highlight the area you want to address and the meshwork is calculated and processed locally, where you can then designate your margins that are exported to CAD software along with the jaw model, the opposing, the pre-op and the bite.
This is a preview of the models that you can export and send to a lab or take directly to design software for chairside milling.
Alternatively, the traditional way would be to not place the margins in the native Medit software and to place it in the CAD software itself. As you can see both options are very viable and you do not lose any resolution of the scanned data between the imaging program or the design software.
In this particular case, we designed an occlusal splint for a patient that is a heavy bruxer. We captured the bite by having the patient gently bite down on cotton rolls on both sides. The first purpose of this is to block out the tongue and the orophayrynx when imaging the buccal bite. But it can also help you find the proper vertical dimension and dramatically reduces the time it takes to deliver an appliance.
Ideally, you place the cotton rolls in such a manner so that you don’t obstruct your view of the second molars. This allows you to see and verify the proper clearance in the most critical area! If you take it one step further and design the guard to the opposing, your seat appointments are just a few minutes long.
Once the upper jaw and the lower jaw are related to each other in the medit scan, and the clearance is verified, the models are brought into exocad’s Bite Splint Module. The case is designed in the CAD software and then milled with a 5 axis milling machine. This step should ideally be delegated to a lab as it is not practical to fabricate these in the office.
The delivery of the appliance is very predictable when you capture the bite with digital impression and you don’t have to grind away to get the jaws to close in the anterior, as the distance was taken into consideration during the design process.
