What Your Lab Tech Wishes You Knew About Your Denture Orders

October 10, 2019

Dentures are labor-intensive and time-consuming prostheses for both the lab and the dentist. Our lab expert shares some insight on ways to ease the burden for both of you.

Dentures are labor-intensive and time-consuming prostheses for both the lab and the dentist. Our lab expert shares some insight on ways to ease the burden for both of you.

The most labor-intensive and time-consuming dental prostheses are dentures, for both you and your lab. With more steps and less margin to work with, dentures can also be frustrating. We spoke with a lab expert to get insight on what could make the whole process more comfortable for all involved.

Josh Gall, General Manager of Axi Dental Lab, says getting the correct bite registration is the most significant challenge for both dentist and lab.  The lab needs the correct bite in a comfortable vertical for the patient to set dentures. Plus, both the lab and the dentist want to ensure that the teeth line up with the midline.

“There’s a lot of little things that come into play, and yes, the whole, ‘Measuring twice, cut once,’ and ‘It's all in the planning,’ and all of those clichés work for this situation,” Gall says.

One of the trickiest things is when the lab doesn’t get adequate bite registration back from the dentist. However, Gall says he understands why bite registrations can be less than optimal at times, especially for an existing edentulous patient who is ordering a new set of dentures.

“How do you take an accurate bite on somebody that has no teeth? How do you articulate something that doesn't have anything opposing it? Because they're not going to bite gums-to-gums, if you will,” Gall says.

There are some golden rules when it comes to creating a denture concerning ideal spaces and openings for patients. However, for existing denture patients that have been in a denture for a long time, there are other biological factors at work, Gall says. There could be bone resorption or the loss of vertical because their bite collapses over time.

“How do you accommodate that?  How do you get them back to where they were before they started that previous set of dentures?” Gall says of the dentist’s challenge during bite registration.

Also, there could be corrective factors at work. The dentist might adjust the opening there because of temporomandibular joint (TMJ) issues or jaw relationship troubles.

“So, I get it. It's not the easiest thing for the dentist. We try to give them all the tools they can when we start to make that job as easy and predictable as possible,” Gall says.

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A Disclaimer & Problems with Poor Bite Registration

Gall hasn’t had a significant issue with resets on denture prostheses. He feels fortunate to work with experienced dentists who give his team the proper indication and the right opening.

However, it isn’t always perfect. Sometimes, the problem doesn’t stem from the doctor at all. Sometimes it’s the patients who don't know where they are supposed to be with their bite.

Gall gives an example of a worst-case scenario where the patient bites one way on a Tuesday but bites differently at the try-in. So, the lab moves all those teeth to the new bite. At the next try-in, the bite is off again, only this time maybe the teeth aren’t touching the way they were intended or are off the midline. Now, the lab resets again. The process is trial and error.

How to Fix Registration Insufficiencies

The bite problems in Gall’s example do not happen every time. Most cases he receives are excellent., and he has only had a couple of patients that had multiple resets.

However, when there have been multiple resets, Gall and the team try to figure out how some dentists have improved bite registrations and, as a result, enjoy more predictable outcomes.

Following are tips and tricks for different bite registration problems. Gall says that taking the extra minutes to do these things could save hours of chair time and additional visits that cost you money.

Double and triple check the bite and occlusion record before sending it back for a reset.

In the worst-case scenario he describes, Gall wouldn’t attribute the problem to a lack of skill on the part of the dentist. It could be that what feels comfortable for the patient today doesn't feel the same the next time.  Gall says if the dentist knows it's a tricky patient and the lab has done more than one reset,  taking the opportunity to double and triple check the bite and occlusion record could help. 

“So, some dentists maybe don't take the time to do that. Maybe they just put it in kind of visually, line things up and think, ‘Okay, that's great.’ Then, they send it back to us, we reset it, and it's off again,” Gall says.

Gall says some dentists have the patient put the dentures in and then swallow. This activity tends to put their jaw relation in the most optimal, comfortable centric occlusion point that works. 

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Take a few teeth off the try-in

Another suggestion is taking some of the teeth off the try-in prosthesis. Then, instead of trying to get all of it perfect, you can try to get the bite correct on the front teeth, for example.

Once you remove some of the teeth, the dentist could put the try-in back in, have the patient swallow, and see if the patient can get into their “natural bite.” Sometimes in difficult cases, Gall says, the only way forward is to take a step back.

Reduce the height if necessary

Gall says you shouldn’t feel bound by the height the lab has given you. When taking the bite registration between the wax rims, examine it to see if you should shave some wax away because the patient’s open a bit too much.

“If you don’t feel that’s right for the patient, trim a little wax off of there and maybe use a little bit more of the bite registration material,” Gall says, adding that the height adjustment helps the lab make a better fit.

“Perpendiculate” in the occlusal rim

He also suggests using Q-tips or sticks to line up the midline. Put two of them in a crossed perpendicular pattern to show the midline.

“It shows us that you lined up the midlines and have a horizontal plane that you want to set to,” Gall says of the perpendicular indication of the midline. “Taking a little extra time on that first occlusal rim step would be the best trick that I could recommend.”

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Things You Haven't Thought of Yet

Getting adequate bite registration is a significant challenge of denture production, but it is hardly the only area that can affect the outcome of the prosthesis. Here are a few things outside of the bite registration that you can do that make a big difference to your lab.

Give the lab more details about the person who will wear them

Gall isn’t suggesting you send the whole patient record or anything that would violate HIPAA regulations. However, knowing the patient’s age and whether this is their first set of dentures or a replacement makes a difference in how the lab sets up the angle of the teeth.

“If they had been in dentures for a while, you want a passive, flat-plane occlusion that is very easy for them to move around in,” Gall explains. “Somebody newer to dentures or a younger patient, we could use a little steeper angle on the teeth and give them more intercuspation to chew with.”

Have conversations about upgraded removable prostheses

Gall encourages dentists to be more open to doing a preliminary evaluation of the case before determining how to proceed. The lab can help patients who have been in dentures for a while improve their denture retention and restore their smile, he says.

Implant-retained dentures or “rebuilding” the ridge with a bar-type denture increases the height and can aid denture retention. It also addresses the sunk-in appearance long-time denture wearers often suffer.

“We're adding a bar in there to restore some of their height and get their jaw back open a little bit and give them a more full-face look again,” Gall says.

Incorporating implants with removable work is an option for many cases. Moreover, many clinicians can place the implants themselves using today’s technology, which can streamline the process when compared to involving a third-party surgeon.

“Be open to working with their lab, whomever it may be, to pick the best-suited option for that patient,” Gall says. “Instead of just making a new plastic denture, maybe spice it up a bit and do an aesthetic enhancement while restoring with a better functional appliance for them.”

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Take advantage of advances in denture fabrication

Along the same lines as the new ways to retain removable dentures, Gall says dentists should consider the new ways to fabricate dentures. Digital dentures have improved a lot and continue to make new breakthroughs.

Up until now, digital dentures had some drawbacks on the material side, Gall says. The materials used in digital fabrication were more brittle than the traditional acrylics that labs use. However, that has changed.

“Some of those traditional manufacturers have entered the digital age and provide their materials to support a digital workflow,” Gall says. “Now, I could mill a denture today out of a material I trust, like a Lucitone 199.”

Another early drawback with digital fabrication was that scanning technology was not sufficient. Scanning soft tissues have always been an issue. However, per Gall, scanning technology is also much better.

“Intraoral scanning cameras these days can get a much more accurate scan of soft tissue, something that you could trust is going to be accurate enough to build a denture on, and that’s going to be comfortable for the patient and retentive, all from a non-physical intangible style of workflow,” Gall says.

While digital dentures are a little scary for some dentists, those who embrace technology enjoy many benefits. They can use a digital scanner and send the file without taking physical impressions. Gall says the lab could then produce a digitally mocked-up denture that could take a bite, as well as check tooth and mold size in one visit, reducing the number of visits needed for dentures and speed up the chair time for them, too.

“It’s up to the lab to be familiar with those options,” Gall says, “but the dentist should get a little experience under his or her belt, too.”

There are drawbacks still, of course. Not everyone is using the technology for dentures, and the costs are still high for a fully digital workflow. Also, it’s new, and it can be challenging to get used to when you have been doing it the old way. However, Gall says that will change in time.

“Acknowledging the technology can also help improve this whole process for everybody,” Gall says.