Restoring Implant Bridges with CEREC® and Atlantis
There are multiple workflows for restoring implant supported bridges with CEREC. The CEREC Chairside software and TiBase workflow is a good option for restoring single implant crowns, but this workflow is much more labor intensive for restoring bridges. This is the typical CEREC TiBase workflow for implant bridges:
- Scan the retainer implants with a Dentsply Sirona ScanPost
- Design individual split restorations for each implant
- Mill only the abutments
- Bond each abutment to a TiBase
- Bring the patient back to insert the abutments and re-scan in the mouth
- Treat the abutments as teeth and design a conventional bridge
The Atlantis workflow allows for the retainer implants to be similarly scanned but using an Atlantis IO FLO ScanBody. The scans are sent via the Connect software to Dentsply Sirona Implants. On the prescription, the clinician can request to make the abutments parallel in order to have a passively fitting bridge. A core file is then returned to design and manufacture the bridge. This workflow involves less appointments and results in an excellent fitting bridge. These are the steps in the typical Atlantis workflow for implant bridges:
- Scan the retainer implants with an IO FLO and send via Connect to Atlantis (Dentsply Sirona Implants)
- Request parallel abutments and approve design
- Open core file, design, and manufacture a conventional bridge
- Seat abutments and bridge
This case involved a failing bridge from #18-21 (images 1 and 2). Both #18 and #21 were non-restorable. The patient had an Axeos CBCT Scan and an optical scan with CEREC 5.1.2 Chairside software. Teeth #19, 20, and 21 were virtually extracted from the model (image 3), and implants were planned in SICAT 2.0 software at positions #19 and #21 (Image 4). The restorative plan was to fabricate a three-unit bridge from #19 to #21. Two CEREC Guide 3 surgical guides were fabricated to ensure proper implant placement (image 5). The bridge was sectioned, leaving #18 in place to help support the surgical guides (image 6). Tooth #21 was extracted, and implants were placed at sites #19 and #21 (image 7 and 8). Tooth #18 was then extracted. IO FLO ScanBodies were placed and imaging was done to fabricate custom healing abutments for implants #19 and #21 (image 9). The stock healing abutments were screwed into the implants, and sutures were placed (image 10). The IO FLO scan was sent to Dentsply Sirona Implants. The prescription for the custom healing abutments was submitted on the Atlantis Weborder site, and a design was ready to approve within a few hours (image 11). The custom healing abutments arrived two days later. When the patient returned for the one-week post op, the stock healing abutments were replaced with the custom healing abutments.
Image 1. Pre-op radiograph of failing bridge #18-21
Image 2. Pre-op bridge
Image 3. Optical scan of pre-op bridge virtually extracting #19-21
Image 4. Implant planning in SiCat 2.0 implant module
Image 5. Designed and milled surgical guide
Image 6. Bridge sectioned and removed
Image 7. CG3 surgical guide for position #19
Image 8. Guided ostetomy for implant #19
Image 9. IO FLO scan at time of surgery for custom healing abutments
Image 10. Completed surgery with stock healing abutments
Image 11. Atlantis designed custom healing abutments
The advantage of the custom healing abutments is to develop perfectly contoured tissue during the initial healing process. After the implants integrate, there is an option to alter the healing abutment design in order to create the final abutments using the same contours. This eliminates the need for imaging after healing. In this case, however, the decision was made to have the patient return for new imaging. At ten weeks post-surgery, the implants were imaged with IO FLOs for the final abutments. The file was sent to Dentsply Sirona Implants via the Connect 5.1 software. A prescription was filled out on Atlantis Weborder requesting parallel titanium abutments with concave emergence and tissue support for implants #19 and #21 (image 12). An insertion guide was also requested to ensure the abutments were placed in the correct position.
Image 12. Atlantis designed final abutments
A few hours later, the core file was ready. The model, with abutments #19 and #21 virtually placed, was imported into the CEREC Chairside 5.1 software (image 13). A three-unit zirconia bridge was designed and manufactured (image 14). On delivery, the custom healing abutments were removed, the final abutments were torqued into position with the aid of the insertion guide, and the zirconia bridge was cemented with RMGI cement (images 15-18). There was no need for anesthetic and almost no tissue blanching. Due to precise digital imaging of the gingiva with a Primescan, the final abutment contours were a perfect match of the custom healing abutment contours.
Image 13. Core file of virtually placed abutments
Image 14. Designed bridge #19-21 from core file
Image 15. Insertion guide with abutments and milled Zirconia bridge
Image 16. Abutments seated and torqued with insertion guide
Image 17. Final titanium abutments #19 and #21
Image 18. Final cemented bridge #19-#21
The Atlantis workflow produced perfectly contoured and parallel titanium abutments, without having to fabricate the abutments chairside or bond them to a TiBase. As an added bonus, the core file that was included with the abutments allowed for the final bridge to be designed and fabricated without having to place or scan the abutments intraorally. The Atlantis workflow not only produces a precise fitting implant bridge, but it saves valuable time for both dentist and patient.
Great case Dan. I wish we could do azento with multiple units. Would be great for anterior cases with multiple implants and being able to temporize that day
This is great. I just wish Atlantis would offer a screw-retained option for bridges as well.
Farhad
The precision of the fit of the bridges amaze me every time. I dropped an anterior implant bridge in yesterday 6-11.. didn’t have to touch the bridge. Just fell into place. The technology is incredible
On 6/24/2021 at 12:48 am, Patrick Oconnor said...Anyone know if Atlantis or truabutment support blx?
Truabutment is supporting Straumann BL RC and NC - however not BLX to my knowledge.
Atlantis - Straumann BL RC and NC as well as Standard/Plus RN and WN.
Wow, great case! Exactly what I am looking for as a bridge solution on two implants. Did you only use one guide for the posterior implant?
Great case! Personally I like using Tru Abutment because the Tru abutment scanposts allow the flexibility to decide after I scan to see if I want to keep the case in house or send it to a lab. With Atlantis I feel like that I am committing to an outside lab once I use there scanposts.
Dan,
I've really struggled to get the titanium from shadowing on these.
I'm used to the beauty of zirconia abutments as the substrate. Zirc looks perfect just subgingival, but the depth I've found I need to place the titanium is too far subgingivally for my liking.
In your photo 17, how far below are you? 1mm?
It still throws a shadow there in photo 18. Have you managed to find a sweet spot for depth whereby the aesthetics are good enough to be used for anteriors? If so do you mind sharing how far subginhivally you request the margin?
Farhad,
Would you ever consider removing the hex engaging portion of the abutments?
If so do the abutment jigs hold them firmly enough to remove the hex, seat with the jig and then screw them in place accurately? If the jigs could it would make for a simple conversion to a cement retained bridge.
Would Atlantis offer non engaging abutments for this purpose?
On 6/24/2021 at 9:35 pm, Shirley Cheong said...Wow, great case! Exactly what I am looking for as a bridge solution on two implants. Did you only use one guide for the posterior implant?
Shirley, I used 2 separate CG3 guides for this case.
On 6/26/2021 at 1:04 am, Damian Chung said... Dan,
I've really struggled to get the titanium from shadowing on these.
I'm used to the beauty of zirconia abutments as the substrate. Zirc looks perfect just subgingival, but the depth I've found I need to place the titanium is too far subgingivally for my liking.
In your photo 17, how far below are you? 1mm?
It still throws a shadow there in photo 18. Have you managed to find a sweet spot for depth whereby the aesthetics are good enough to be used for anteriors? If so do you mind sharing how far subginhivally you request the margin?
I agree Damian, even gold color abutments can tend to drop in value at the gingival margin. This case had a 1 mm deep facial margin. I try and do screw retained in the anterior so that I can drop the facial margin deeper to 2 mm, I can usually do that with an angulated screw channel, but I not always. I find bonding the crown to the abutment with a very opaque cement like Multilink Hybrid abutment cements does really help reduce that graying or value drop. Clean up is a little harder with it since it has no photo initiators for light curing.
Regarding your other question for multi unit screw retained, stay tuned.
Zirconia is pretty opaque. Are you talking about shine through with eMax? I have not noticed shine through with zirconia on titanium.
For sure Charles. I'm talking Emax.
For me chairside zirconia is "generally" too ugly to use anteriorly anyway.
If using chairside zirconia it's probably in an area of low aesthetic demand where shadowing doesn't matter too much.
