| This is a really cool case I just wrapped up planning that I wanted to share. This is about as complex as guided/implant cases get so I’m going to walk through the thought process and how I execute these. |
Here is the CT scan opened in Blue Sky Plan. Pt has numerous missing teeth and extensive decay throughout the mouth. The treating doctor planned to edentulate her and do 6 implants per arch and fixed immediate load prosthesis
The intraoral scans stitched to the CT
You might think that the way to start would be in planning implants but we really can’t adequately plan implants unless we know where the ideal teeth should be. So my starting point is always to begin by treatment planning the photos. This is my little powerpoint template I posted about a couple weeks ago. If you reach out through our website, I’m happy to send it to you. It’s really beneficial for smile analysis and smile simulations. You can see the extensive decay present. Midline good…….incisal edges too short……..reverse smile line……..empty buccal corridors. Definitely a lot we can improve upon. Also noticing pretty big masseters so we want to over-engineer this case as much as possible.
The lateral view helps me know if the teeth need to be brought out more facially and also helps in analyzing incisal length when referencing the wet dry line of the lip.
So the template has many smiles to choose from for smile simulations and I went with this one first because I thought it would be a good one for filling out her buccal corridor………..I was wrong! This one did not look good at all to me. In analyzing it, I think the buccal corridor is too toothy. So I went back and found another smile in the library that had more of a Ushaped arch form more similar to her current teeth.
Here I’m aligning everything and scaling it. I put the incisal edge just above the wet dry line of the lip; I scaled it to make the anterior 6 teeth be the same width as her nose; I also stretched the length of the teeth upwards because her original smile seemed gummy to me.
Here’s the second simulation which I thought fit her face much better. This is the one i chose to go with and I’ll use it to guide my 3d waxup
I ALWAYS save this picture as a reference for when I’m doing the waxup. This is the simulation I like turned down to 50% transparent so that I can correlate her existing teeth to the changes that need to be made.
So now, I’m ready to do a digital waxup. The maxillary arch is all I’m really focused on initially since it drives the esthetics. I do my waxups in the BSB Denture Module because it lets me pull in an arch of teeth all at once and quickly scale and align them
Again, the transparency function lets me reference back and forth between the 2d simulation to ideally position things. Once the max is set, we just set the mandibular dentition to it.
Completed Digital waxups
NOW, we’re ready to begin positioning implants. To get the 6 implants into the premaxilla was very challenging but we were able to do it by distoangulating the posterior implants along the sinus wall and using 30 degree abutments to determine where the screw access would emerge.
Prosthetic emergence is set to come through occlusal surfaces or just lingual to the incisal edges.
Mandibular planning was very similar except here we’re doing a couple shorties distal to the foramina to increase A-P spread.
At this stage, we send it back to the doctor for approval before going on to fabricate guides. Once they do, then the fun begins.
We knew this would be bone supported guides because of the depth the implants had to be at for prosthetic space. So if you are doing bone guides, you have to do bone segmentation to make STL’s of the jaws. I go a step further and cut the teeth off the bone segmentation model and combine back in the high quality teeth shapes from the stitched intraoral scans.
The reason this is important is because I’ve recently begun making the bone reduction guide such that it’s connected to a tooth guide for super accurate positioning. I’ll make the bone reduction guide and the tooth supporting section so that they both have the same path of draw and will have no interferences seating as a unit.
Printed models for testing all guide fits
So I take this bone/teeth model into the denture module just for purposes of generating a path of draw model. All undercuts get blocked out so it can seat as a unit.
Path of draw model to build guide on.
Now I’m ready to make the guide which I call the “pre-reduction guide”. What’s unique about this workflow is that I really only make a single guide in BSB. However, I’ll repurpose that same guide to function as the pin drilling guide, reduction guide, and the drill guide. It will even serve as the positioner for the temp prosthesis. It’s important to draw an overly generous guide boundary. It’s super easy to cut things back if they’re too over-extended but it’s a huge pain if they’re not extended enough to start with. Also the only tubes you should have turned on at this stage is the lateral pin tubes.
Completed “pre-reduction” guide made on that path of draw model. This is what I’ll turn into the reduction guide, drill guide, and everything else.
Showing upper/lower pre-reduction guides.
So what I’ll do next duplicate this guide…….on 1, cut away everything except where it sits on the teeth. This will serve as the positioning index for the initial pin placement and reduction guide. Then on the other duplicate, you can make the bone reduction cuts to generate a reduction guide. Finally, I’ll go into mesh mixer and just connect these 2 with some tubes. The idea is that you’d flap, seat this guide completely on the teeth which in turn perfectly positions the bone reduction guide. This allows it to be stable while you drill your pin osteotomies and pin it into place.
This picture is just showing the pre-reduction guides and the pin placement and reduction guides superimposed on one another. As you can see, they are one and the same…….it’s just that I’ve cut them into the shapes I want.
Flap, seat this, drill pin holes, and pin into place.
Once pinned in, you can just take your drill that you’ll do bone reduction with and zip through those little tubes which allows the tooth indexing section to fall away. I’d recommend doing extractions at this point before reduction. It adds a little support to the buccal bone having this guide in place and helps prevent blowing out a buccal plate during extractions. After extractions, use the drill to reduce bone down to the plane of the reduction guide. Note that it’s a buccal only guide.
Here’s the jaw shape after bone reduction.
Model work we include so you can test fit everything and do mock surgery if you want.
You don’t want to be drilling on printed plastic so I already have the implant sites subtracted out where the drill can penetrate into the space without dulling them.
Reduced Maxilla ready to seat the drill guide.
After reduction, just unpin and throw away the reduction guide. Now you’ll seat the drill guide. If you look closely, this is nothing more than the same reduction guide but with the guide tubes added in and connected with some tubes. Again, I’m just making 1 original guide and then repurposing it into these multiple forms. The fact that it’s the same reduction guide is advantageous because you know it will be able to seat and pin in the exact same way. When your pins go to place, you know you’re seated properly
This is just zoomed in on one of the angled implant showing the timing marks on the guide tube. Each of these lines corresponds to where the flats of the implants should line up. This is super important if you want the angled MUA to line up and emerge through the prosthetic in the planned position. This case is using the BSB fully guided kit so the guided driver has 6 notches that correspond to the flats on the BIomax implant. Drive the implant to seated position and then just make sure to align a driver notch to one of the timing marks.
Buccal only upper drill guide on the models
Note the tubes are floating with this design so hypothetically, you could not reduce the bone all the way and this would still seat without interference
Timing mark on the mandibular guide
Tubes floating off the ridge
Finally, we need to make the immediate load prosthesis. Since we’re doing things guided there’s no sense in doing a denture conversion. We can take the waxup done at the beginning of the case and just turn it into a fully contoured prosthesis. In this case due to spacing issues, it was necessary to make more of an FP1 design on the maxilla. They are designed such that the intaglio of the hybrid or pontics sits exactly 3mm off the level of the reduced jaw. To position it into the right VDO and A-P position, we’ve just repurposed the original bone reduction guide (again). This will pin into place just like the previous ones (because they’re all different versions of the same guide) and position the prosthesis into the planned position.
You can also see that there is a 2mm hole on the facial of each implant site so that for the pickup, you can just fill a syringe with acrylic, stick the tip into the hole and inject. This beats the heck out of doing a salt and pepper pickup. Salt and pepper is difficult anyways here because the size of the holes are so precise.
Notice that the intaglio is fully shaped so there should be no need to recontour anything. The only modification you’d do after the cylinder pickup is to cut those sacrificial supports connecting it to the positioner and trimming back any acrylic overflow from the pickup. These are 3d printed in Bego Varseocrown which is super strong and has been performing really well for me. From a surgical perspective, most people will suture the tissue before pickup but that’s got a lot of problems. The ridge will be convex so when you do it that way, your intaglio will always turn out concave and uncleansable. What me and Danny Domingue have figured out after doing a ton of these is that it’s far better to wait until the very end to suture. We just published an article on this called “the full arch healing abutment”. The idea is that if you pre-design the intaglio to be perfectly contoured and simply suture the tissue TO THE PROSTHETIC at the very end, the tissue will have to form itself to the shape of the prosthetic which makes it more cleansable and gives a more natural emergence profile as if it’s coming out of the tissue.
(Pics from a different case) The way Danny does it is he completes the pickup and removes the indexing guide. He’ll do any grafting needed and then place 2 prf slugs over each implant site.
Then he’ll screw down the prosthesis THROUGH the PRF sandwiching it into place and stabilizing it. Then just a large horizontal mattress suture on each side of the arch to pull the flap edges up against the temp. If the flap moves any at the midline when they move their tongue, you should add one more at the midline. That’s it! Usually 2 and at most 3 sutures! DO NOT TRY TO REAPPROXIMATE THE TISSUE EDGES!
This is the beauty of the full arch healing abutment technique………you get massive gains in keratinized gingiva as a byproduct. Think about it……you have the temp pinning down a ton of PRF that is sitting directly atop the bone. The eliminates a lot of the pain, keeps the bone from being exposed, protects any graft, and speeds healing and vascularization. The flap edges will be far apart from one another sitting on either side of the prosthesis. However, we know from the old perio lit that if you’ve made an incision entirely within KG, it doesn’t matter how far apart the tissue edges are left to heal, it will always close the entire gap with KG. Here we’re exploiting that to get a large fibrous bed of KG with the added benefit that it’s properly shaped itself to the temp. There’s simply no easier way to get such huge gains in KG or to develop a proper emergence profile that is cleansable for long term maintenance.
The goal is to make the conversion so easy that an asst. could do it.
Here you can see the hole size where the temp cylinders will emerge. Cylinder is about 3-3.5 mm and hole is 5mm
Finally, we create a set of CYA dentures just in case the implants don’t torque enough to immediately load.
| Conclusion: |
| That’s it! Hopefully I explained it well enough but I’ll tell you anecdotally that we’ve done tons of cases like this now……..many in front of 20-30 people in live surgery courses and the speed and accuracy at which we can finish a case like this is insane. At the last course at Danny’s office, we did a complete lower arch with this protocol in 1 hr exactly from incision to pt leaving with an immediate load prosthesis. I hope you can see why when I hear the old, tired guided vs non-guided debate, I just roll my eyes at this point. It’s not a question of “can you do a really nice job freehand?”……..of course you can! However, there’s no way you can do it to this level of precision or speed. THAT is the reason we do these guided. |
