Segmenting an Airway???

Part of the cool thing about my job now is I get paid to sit around and brainstorm ways to stretch the applications of our current technologies.  This is a great example of that.  I don’t necessarily know all the implications of this yet but I’m certain that going forward there will be many.

One of the big areas of growth in dentistry right now is sleep apnea.  To be honest, it was never a big interest of mine as I was more into the blood and surgical treatments.  However, one day as I was segmenting the jaw in Blue Sky Plan, I happened upon this technique and decided to just see what I could do with it.

The result was that I could turn all the air spaces withing the head into an STL model.  So why does it matter?  Well, I’m not entirely sure yet but I could foresee that this may be used in the future for evaluating anatomic anomilies that put patients at risk for sleep apnea.  I could imagine that ENT’s would find this useful in diagnosing constrictions in the airways or even cancers impinging on the airways.   If nothing else, I can imagine that it would be a valuable tool for helping patients to evaluate what’s going on in their airways and why it may be necessary to treat their sleep apnea.

If you are dorky enough to watch this video, I hope you’ll weigh in on the comments and perhaps discuss some potential applications for this.  It would not be a difficult thing to automate within the software if we decide that it is worth doing.

What do you think?!

What if Your Surgical Guide Could Become the Transitional Restoration?

This was a really interesting case I teamed up with my friend Dr. Rusty Fitton on.   Right now, it’s all the rage to restore an edentulous patient by cutting off a ton of bone and restoring them with an All-On-X restoration.  However, there’s a lot of value in being able to preserve all that bone when possible and just restore them with old fashioned, crown and bridge dentistry.  This was just such a case.

This patient had an ill fitting upper denture opposing natural dentition.  The midline was way off and initially I felt there should be some additional length added. 

I always preach that you have to start with the end in mind on these complex implant cases so since the existing denture was less than ideal, I wanted to figure out where the teeth belong first.  A critical step in these types of cases is to cbct scan the patient (dual scan protocol) at the intended vertical dimension that you want to restore them at.  

By doing this, the existing denture can be imported into Blue Sky Plan and used as a point of reference for redesigning the smile.  The first step was that I did a new digital waxup in Exocad where I thought the teeth should be.  I had Rusty print that model and make a putty matrix on it to transfer it to the mouth.  Here are the results.  It’s decent at normal smile.

At full smile, I think they’re too long.  

Also, the midline is still not quite right

One of the huge benefits of digital is that rather paying $50 a unit for a new waxup, I can just pull the files back into the software and redesign the waxup based on the changes I want to make.  The cost is a whopping $0.00.  Here is what the redesigned waxup looked like- a little shorter and midline shifted even more.  The blue is the initial waxup and the orange is the corrected one.

Now that I’ve finalized the tooth position, it’s time to plan the implant positions backwards from that.

This patient was a rare unicorn in that she had adequate bone everywhere that it was needed to position the implants such that the emergence of the screw positions was lingual to incisal edges  and right through the occlusal tables of the posterior teeth.

Now here is where it gets interesting.  It’s pretty easy to make a transitional prosthesis when you have a lot of bone reduction and a thick denture to convert into the prosthetic.  However, when you’re trying to do it as a traditional bridge, every single millimeter of space counts and precision is critical.

My idea on this case was to actually make the interim bridge become the guide.  Here’s how I did it.  I opened the bridge in Meshmixer, a free CAD software, and I performed a Boolean subtraction of the guide tube positions from the bridge.  

Then, I exported the guide tubes for the Blue Sky Bio Fully Guided Keyless Kit and combined them with the bridge.

In theory, the bridge can now be used as the surgical guide.  The obvious problem is that there is so little tissue contact that indexing it becomes near impossible.  It would really be a benefit to have a tissue base, similar to a denture base, to index this into position and maximize the contact area of the seating base.  So to accomplish that, I created a “guide” directly on the tissue surface that had all the tubes turned off except for the pin tubes.

Now I need to find a way to combine this tissue base with the “bridge guide”.  So to start, I open the “bridge guide” and I offset, or inflate it, by 1.5 mm.   Then I perform a boolean subtraction of that inflated bridge from the tissue base.     

Now import the “bridge guide” again.

Now, it’s beginning to come together…………a full arch “guide” and bridge in one.   The only thing that I need to complete is to connect the two objects.  This is easily accomplished in Meshmixer by using the select tool to select small areas of the bridge, “transforming” them and pulling them until they contact the tissue base.

This creates a single object that combines the bridge and the tissue base of the guide.

BOOM!   This is the end result.  It’s a full arch surgical guide that you can pin into place and perform the guided surgery though the guide, place the implants through the guide, seat the prosthetic components through the guide, and perform the pickup through the guide.  Once the pickup is complete, the little sacrificial supports can be cut which allows the entire tissue base to fall away leaving the transitional bridge with all the implants connected.

This STL can be printed in crown and bridge resin or milled with a 5 axis mill in PMMA or composite.  Finally, I incorporated some articulation pins that allow me to index the maxillary guide/prosthetic to the mandibular teeth.  The enables me to create PVS bite matrix to properly position the guide into place before pinning it into it’s definitive position

Finally, I also printed the guide/restoration in NextDent Crown and Bridge Resin on the Moonray S printer.

For the surgery, Rusty will place this into the patient’s mouth, have them bite down into the putty bite to ensure everything is in the right position, then drill his pin holes to pin the guide into place.   Once the pins are in place, he can perform guided surgery through the guide/bridge and place all the implants to their final positions.

The prosthetics can be placed and the pickup can be completed without ever removing the guide.  Once everything has been picked up, the sacrificial supports can be removed allowing the tissue base to fall away leaving just the final bridge.

This is the first case I’ve ever designed like this but, if successful, this could change the entire paradigm of how we do guided surgery.  As our printing materials advance, I feel this will become a preferred workflow when the case is suited to crown and bridge as opposed to a hybrid restoration.

I would love to know what you think.  Let me know in the comments!

 

An Affordable Option for Immediate Transitional Hybrid Dentures

I’ve always loved the idea of a 3d printed immediate transitional temporary for fixed hybrids because they’re nearly free to fabricate but the Achilles heel was the strength……I’ve had them snap in half because they’re more brittle. Well, I think we now have a solution that makes it viable.

This post shows how I used a Trilor Arch Bar to give strength to an immediate prosthesis. We are now selling these at BSB and there are literally tons of possibilities with these. The big benefit is that it is incredibly strong, even in small dimensions and that it can be trimmed and customized chairside.

This is just a demo model and not a clinical case so don’t start with me about it being an All On 3!


OK suppose this is your patient and this is in the mouth, not on a model.

You could take a piece of pink wax and index the positions of the multi unit cylinders.


Here are the Trilor arch bars- they come 3 to a box


These come in 3, 5, and 7 mm thickness. These are 3mm thickness in this case. I wanted to use the smallest dimension to really see how strong this stuff is.


You can lay the pink wax template over the bar and mark your holes


Now just use a lab handpiece to punch through.


Once it fits over the cylinders, you can begin trimming down the overall width


When you’ve got it roughly shaped (and again, remember, this is done chairside), you can perform a pickup using the material of your choice to bond it to the cylinders.


This now creates a passive and extremely rigid/strong bar across the multi units


For this application, I’d suggest trimming slightly on the underside to make a high water design. This allows it to be encased in the pink acrylic once the pick up in the prosthesis is done.


For my prosthesis, I just 3d printed a denture that I designed in the soon to be released Blue Sky Bio Denture Software. But this could have just as easily been the patients existing denture hollowed out or a lab fabricated shell denture. Use whatever you have at your disposal.


Printed base design with denture tooth sockets


teeth in place


Here you can see the underside.


So I printed the base in Nextdent Denture Base and then the individual teeth were printed in Nextdent Crown and Bridge resin.


Here you see the final printed denture (cost me under $5). But don’t get hung up on the prosthesis type. This could also be a shell denture or the patients existing denture.


Get this fitting over the bar


In this example, I picked up the bar first, then imaged and designed the denture. Obviously, you will not be able to do that with an immediate conversion because it takes time to design and print. But you could do it and deliver later that day or next morning. The big advantage is that it will make your pickup more precise and maintain bulk of material so you’re not doing a lot of shaping outside the mouth

You can see how precise the “bar” fits inside the printed denture.


Long screws were placed and holes were created for them to do the pickup


Now use pink acrylic, composite, pink bisacryl………..whatever material you like to complete the pickup of the “bar” in the denture.

Once the pickup is complete, you can cut off the flanges, and shape the underside to be cleansable


Here is the final temporary prosthesis


It has a cleansable intaglio side and the Trilor bar is completely encased.


Most importantly, this is incredibly STRONG. I’m not a small feller and I squeezed this with all my might and couldn’t break it.


The weakest link here is not going to be fracture of the prosthesis but rather chipping of individual teeth. For this reason, I wouldn’t make my definitive fixed hybrid by this method. Here’s where we just have to wait for our material chemistry to catch up to the printing technology. However for a temporary prosthesis, this is an more than adequate and it’s very affordable to create.

My all in costs here were less than $100 for this transitional prosthesis and

This is but one application of these arch bars but there are so many others. You could make definitive bars with Locator attachments. You could also make definitive prosthesis with these also. Would love to know your thoughts!

Full Arch Guided Surgery at a Fraction of the Cost

$2800!!!!!!!  That’s how much a doctor at one of my courses recently told me he paid the lab for a single arch bone reduction guide and surgical guide.  It stunned me because I’ve been teaming up with clinicians to do these routinely in the Blue Sky Bio Guided Surgery Software for well under $100.   I understand that some doctors don’t want to learn to use software but that is an insane amount of money to spend if you could do it yourself in under an hour.  The only explanation I can come up with is that people just don’t know it’s an option.  They think this can only be done with some super top secret lab software and that it takes a week to plan.  However, nothing could be further from the truth.

This is a case I teamed up with an oral surgeon friend on and we were able to pull off a bone reduction guide, implant placement guide, and transitional prosthesis.  My all in costs were an $18 export fee, 4 guide tubes for $28, and maybe $5-10 worth of printing resin.   THAT’S IT.  The time to plan was under 1 hour.

Now it’s worth mentioning that there are 2 necessary pieces to the puzzle that allow me to do all this.  First, you can’t do any of it without a CBCT scan so that’s the price of admission.  Secondly, I did a lot of 3d printing on this case so being able to do it in house myself was huge.  I use a Moonray S 3d printer.  I have several but currently, it’s my favorite for cases like this.  Finally, you have to learn how to use the software.  There is a ton of free content out there that myself and others have put out to teach the software but there are also live courses.  I give them pretty regularly and others do as well.  See my home page for course dates.   Let me show you how we did it.

Patient presented with a lower partial and a few remaining lower teeth.  A dual scan was done meaning a scan was taken of the patient with radiographic markers on the partial and then the partial was scanned by itself.  The BSB software allows these to be merged as seen below.  Secondly, when doing bone level guides, you have to segment the bone- in other words, you have to turn the CBCT rendering of the jaw into an STL model.  This can be done in the BSB software too but it can be tedious.  I often delegate this task out to Image3DConversion and they do an excellent job with 24 hour turnaround.

The implants should be planned from the prosthetic endpoint backwards.  I try to have the anterior implants emerging lingual to incisal edges and the posterior implants emerging through the occlusal of the teeth

Bone reduction guides can be made in BSP by creating a “guide” direct on the segmented jaw STL but with no holes in it. You want to create a simultaneous cut through this guide and the jaw and the same time but BSP will only cut one stl surface at a time, not two. Solution: Export both together and then bring them right back into BSP and now they are 1 surface and you can use the cut tool to make the bone reduction cut between the guide tubes and the platforms of the implants.

I 3D printed a practice model of the jaw to be able to do mock surgery.  Always nice to be able to do a “dry run”

Bone reduction completed on the practice model.  It should be taken down to where it’s even with the guide.

Once that is complete, the surgical guide can go on.  This guide is just made it the normal way in the BSB software by turning the guide tubes on and building it directly on the reduced jaw.

For this case, the BSB Fully Guided Keyless Kit was used.  I’m going to dedicate an entire future post to why a keyless guide is the way to go but for now, take my word for it……..keys suck.

Fully guided implies that the implant is placed through the guide as well on a guided carrier as shown here.

Here you can see all the practice jaws and surgical guides on the build plate for 3d printing on the Moonray printer.

I was also able to 3d print a temporary that was fabricated in the BSB Denture Software. Because I know where the multi unit abutments are going to emerge, I can export them from Blue Sky Plan into Meshmixer and do a Boolean subtraction.  This will leave premade holes exactly where the implants should emerge.

Here is the 3d printed temporary prosthesis.  Currently, our materials are a bit lacking for being able to 3d print a definitive prosthesis so this could be milled out of something like PMMA or another easy solution is just print it and then duplicate in acrylic.

I use the Anaxdent large flask for this purpose and it works really well.

The prosthesis gets invested inside and out using PVS putty.

I created an injection hole and a vent hole and then injected acrylic to create the temporary.Here is the temp ready for surgery

Time for surgery

The downside to doing guided surgery on these cases is that it requires a large flap.  You need to fully dissect the mental nerve as you can see here.

Once the teeth are removed, the bone reduction guide goes on.

Here you can see the bone being reduced to the level of the guide.

Completed bone reduction

Once bone reduction is complete, the surgical guide can go on.

The fully guided drills are used to create the osteotomies.

4 Blue Sky Bio Max implants were inserted with very good initial stability

Angled multi unit abutments were placed on the back implants to provide angle correction.

Temporary copings were placed on the multis and then picked up directly in the mouth with acrylic.  Once set, it’s removed from the mouth and any voids are filled and the prosthesis is trimmed and polished.

Very important that the underside be flat or convex so that the patient can cleanse the area.

Occlusion check

Final pano

While this looks complex, it is well within the reach of any dentist or technician that is halfway computer literate.  Furthermore, I think that by doing your own planning, you have so much more control and knowledge of the case and can give your patient a better end result.

Making Your Own Custom Implant Bar in Under 20 Minutes

This is a technique I’ve been loving ever since I first learned about it from  prosthodontist Lambert Stumpel …………. since we know that absolute passivity with a bar is impossible, it makes a ton of sense to build a spacer into the system and pick up the bar in the mouth to get true absolute passivity.   I’ve fabricated fixed hybrid denture frames this way in the past but it was a lot of lab work.  So, I’ve been working to digitize the process so that dentists can and will actually do it.

Very soon, BSB will release software that automates all of this but until then, here’s how I made an implant bar in Meshmixer, a totally free software. This bar is made with .3 mm of “slop space” around the multi-unit abutment cylinders so it can be picked up in the mouth and I’ve also subtracted out 4 holes measuring 1.8 mm in diameter which can be tapped for inserting locator bar females.

Once designed, the STL file is either milled ($$$) or 3D printed in castable resin which can be invested and cast by any lab in chrome cobalt for very little money.  The bar would be picked up using a strong resin cement such as Panavia.

These ribbed multi unit abutment copings are available from Blue Sky Bio.   

There are also spacer sleeves and waxing sleeves available to go on the copings if you want to do it the old school way.

 

Multi unit abutments placed

Multi unit copings placed onto multi unit abutments

Powder was sprayed on the shiny cylinders for scanning with the Shining 3d DS-EX scanner

Here is the resulting printed “bar” 

This was just done for demonstration purposes but if you were really having it cast, it could be printed in castable resin like this

Or, you could just send the file to a lab capable of milling titanium with a 5 axis mill.  I sent this to Burbank Dental Lab and they milled this for me at a drastically lower cost than a traditional milled bar.  It turned out awesome!

Turning a Beauty Center into a Dental Training Center

In May of 2017, I purchased a building just off of the town square in Winchester that had previously served as a beauty shop. It had been vacant for over 7 years and was very run down but I loved the location and I got a great deal on it. I bought it because I needed a place outside of the house to work. I had started to work full time for Blue Sky Bio and I was finding it impossible to get things done at home. Not to mention, my ever expanding collection of dental technology toys was taking over every square inch of our home.  Thus, the training center was born.

Initially my vision was just to use it as a personal office. As we got into the project though, I found I had enough room to actually give courses there too. I had been traveling all over the world and had grown tired of the hotels, the crazy venue costs, and the long hours in the car/airplane so it made a ton of sense to at least try and get people to come to me for courses rather than me going to them. So, I began planning to outfit the space to accomodate dental courses as well.

Since this was going to be where I’d spend most of my working hours going forward, I really wanted it to be a space that I’d enjoy spending time in. I wanted a fenced in backyard for bringing my dog to work. I wanted a full kitchen so I could cook a decent breakfast and lunch without having to leave. I wanted a full bath for showering after working out and in case I ever rented it as an apartment in the future. Finally, I wanted to have a nice place to workout since exercising throughout the day really helped keep my back problems at bay.

In the end I was really happy with the outcome and I now have a place I love to work in. It’s part man-cave and part mad scientists laboratory with a touch of rustic redneck. I did a lot of videos and pics throughout the process. I hope you enjoy!

Initial appearance of the exterior

Interior

Drop Ceiling removal

Removing layers of the walls

Framing

My girls pouring the concrete pad for the back patio and putting in thier handprints

My stand up desk made out of steel piping and reclaimed oak from the old flat roof

New windows installed

Built new awnings over the windows

Paint!

Bathroom vanity made from reclaimed wood as well

My completed work area.  I generally stand all day to work to keep me from hunching over.

Here’s how it looks when it’s set up for a course

  Here’s how Maggie spends most of her day at work with me……  chewing up things she shouldn’t and then sleeping.

My set up for photographing projects I’m working on

 

If you are really bored, here’s some chronological videos of the progress.