The Perfect Bite Registration & Impression

[drm313mac]

araucaria, you are correct, and this is what I was driving at. Sometimes, this is the only solution, though I would prefer a more objective one.

 

[kcdt]

Ken,

1. CR: Your method is what I was taught as well. It is very difficult when the person has a heavy beard. the other method is to watch them close, and where the Masseter begins to activate. Again, difficult with bearded men.
As for the rest, were we trained in the same school?

For normal and straightforward cases, do all your docs use the facebow, especially if the case will be anatomic?

I got good early training for one of my accounts in a state where supervised denturism was legal. Beyond that, I just try real hard to pay attention.

The vast majority of my drs don't even bother with a facebow. I only consider them necessary if you plan to open or close the bite, so as to avoid a check bite.

 

[kcdt]

For rest vertical dimension you can try getting the patient to relax the mouth with lips in contact.Ask patient to gently increase air pressure in an attempt to blow - until the seal of the lips just begins to break and the breath escapes. Measure this position on 2 or 3 occasions at the point of breaking the lip seal. This should be 3 - 4 mm increased ovd. Good estimate imo.
Dont forget some folk need a tissue conditioning phase and rehabilitation to be completed before construction is commenced.

Great points!

 

[araucaria]

araucaria, you are correct, and this is what I was driving at. Sometimes, this is the only solution, though I would prefer a more objective one.

The main difficulty we face is - patients ;
they're all so different and unpredictable - we need an arsenal of techniqes to treat them successfully imo. Best to follow the course that suits their situation. We gotta bend with the breeze or we'll break.

 

[denturist-student]

We are at NAIT in Edmonton....I am in second year and finishing semester 3. We use Accudent system 1 for prelims and aquasil for finals using a closly fitting form fitted tray....Very frustrating to get the knack of doing it because too much material or pressure will cause pressure spots.....If borders are not intact or under or overextended or there is a void int he rugae or elsewhere more than 5 mm, we have to redo the impression.....Have to take a complete oral exam though and asses the boney ridges which may prove difficult to pull off the aquasil on a closely form fitted tray. My first patient was so badly undercut on the lower lingual that we had to use Accudent because Aquasil would have not come out....

I was wondering if any of you folks use a baseplate wax relief when you make your custom trays. A lot of literature I have read advocates relieving the tissue fitting surface. However we are using a tight form fitted tray for now here. Seems to be quite the knack to estimate the amount of material and the pressure to use for a good impression.....I have seen Dr. Massad's videos and he appears to use a relieved tray....

The triad tru tray from dentsply is what we are using here.....Works for me. I can handle it well and make a tray quickly and just light cure it and with minimal adjustments later.

Today we had a lecture on altered cast technique....It was quite interesting that we will have to assess the tissue bearing surface of the partial distal extension and use an appropriate impression material to compress the tissue somewhat so when the case is resting in the mouth it doesn't sink too far....We have access to all of the aqwuasil products both fast and slow set.....Now there is some good advocates for the functional impressions using Bosworth or Viscogel...both of which I have yet to use....Apparently the technique is to apply some tissue conditioner for a few days to obtain a functional impression and then reline....In that way the patient adapts his own impression for a few days....However temporary things have a tendency to become permanent. Supposedly they are a real task to remove if the patient leaves them in for a few months.....I guess that is why the fees are paid up front with relines using tissue conditioners....To get the patients back in to complete the reline......Oh so many things to learn......Take care all.

 

[denturist-student]

Well the 2 mm is just a target for starters. If the patient needs more for phonetics....we get them to count from 69 backwards to 60 and watch the space needed for the sixes....any stray from our target requires justification....and has to be written down in the progress notes....Take Care....Dan

 

[denturist-student]

All of us in our school are sold on the premise that the facebow is an important part of the treatment. We always take a facebow and most of us are taking about ten minutes on it....While it may seem picky, or fussy, it does allow us to open or close the bite by 2 mm. Without it we cannot change the bite at all. Here we are using the Hanau Modular with the programmed fossa....I also have a Whipmix 8500, a Hanau H-2, and a Hanau Wideview along with a springbow and a Denar facebow....but at school I am only permitted to use the Hanau Modular because most of our projects are marked using them.....I rather like the wideview and fully intend on getting an Ivoclar stratos 200 or 300 next time I see one on ebay.....One of my classmates has an Ivoclar stratos 300 and that is one of the smoothest articulators I have seen. And the immediate side shift is built right in....we use a 1 mm side shift for all of our casework....Take care....Dan

 

[drm313mac]

araucaria and Ken;

I was taught to use the full facebow analysis on every case, even the simple ones. We had to do full gothic arch analysis on every case. As you stated though, few actually do this, and within months of being in private practice, neither did I.

Dan;

When using the custom tray, yes, it is relieved, to a degree. That is, when making it we place 2mm base-plate over everything, thus the PVS will have exactly (or fairly close) 2 mm thickness.

Massad relieves his trays. My mentor relieves his. He gets so pissed at me when i use Accudent I stock trays, or Pozzi super-trays.

 

[denturist-student]

Thanks...I suspected so. I have not seen much literature which doesn't advocate at least a 1.5 - 2.0 mm for the impression material to flow out of....However I will have to struggle with form fitted custom trays until my lab and clinical instructors think otherwise. So many of us are struggling with making good impressions with flush fitting custom trays....To me it makes no sense to use a form fitted tray on an alginate preliminary impression anyways...with a closely fitted custom tray the material initially acts like an oil slick and slides around instead of allowing us to control the positioning of the tray.....Added with that, the possibility of a warped tray has visited my classmates and me on a few occassions...Thanks for the input...Dan

 

[drm313mac]

Dan,

You are most welcome, but if I were you, I would ask for the input of the other techs. Hey, I am a dentist, so what do I know?

David

 

[denturist-student]

araucaria and Ken;

I was taught to use the full facebow analysis on every case, even the simple ones. We had to do full gothic arch analysis on every case. As you stated though, few actually do this, and within months of being in private practice, neither did I.

Dan;

When using the custom tray, yes, it is relieved, to a degree. That is, when making it we place 2mm base-plate over everything, thus the PVS will have exactly (or fairly close) 2 mm thickness.

Massad relieves his trays. My mentor relieves his. He gets so pissed at me when i use Accudent I stock trays, or Pozzi super-trays.

One of my instructors advised me that the accudent trays were thermoplastic and could be formed....Also they have a tendency to over extend the linguals especially along the mylohyoid ridge. We have a tendency to overfill the trays...Being that they are thermoformable, they are supposed to be adapted however that is a no no at school....Last year I took an impression of a classmate using system two in a custom tray. Best impression yet and I will use that for all my partials cases this year. We dont use the tips though because hard to find now and only brush on with our fingers. But the system two is far better for recording dental tooth anatomy for a single denture or partial denture....Our course covers anatomy, pathology, radiology, microbiology, pharmacology and is three years in length so being focused on dentures and removables it is quite thorough.

We are using the springbow on all cases.....first two cases tried in without any problems...Aticulation was smooth and accurate....They were setup on Ivolene bases and I have some setup wax for the teeth and also for the pin tracer base. I will get a swissdent pin tracer because they have the adjustable stops which are lockable....That makes locking in centric easier....Have used regisil for bite but will try plastogum on next one.

But I am just a student who what do I know? ha ha ha.

 

[denturist-student]

I have the video of Dr. Massad's impression technique...am thinking of ordering his whole 4 dvd set....oh well maybe for Christmas...

 

[kcdt]

I have the video of Dr. Massad's impression technique...am thinking of ordering his whole 4 dvd set....oh well maybe for Christmas...

You won't be sorry. He lays out a neutral zone technique for the modern practice that is very predictable.
His stuff on the exam phase and using duplicate denture to tissue condition and correct bite is worth it's weight in gold.

 

[denturist-student]

Thanks..appreciate the input...maybe Santa will leave them in my stocking this year...

 

[kcdt]

Massad relieves his trays. My mentor relieves his. He gets so pissed at me when i use Accudent I stock trays, or Pozzi super-trays.

That is why I really like the Massad trays. They are meant to be relieved, they are thermoplastic and meant to be shaped, they are disposable, so you don't have to catch grief for altering something someone wanted to get 20 years out of.

 

[kcdt]

Thanks..appreciate the input...maybe Santa will leave them in my stocking this year...

If you do get them, and you want to tease out the finer points in detail, feel free to PM me. I've worked with the procedure for some time now. Plus Massad is always making additions. There are a few tricks that didn't make it onto the dvd, as they came afterwards.

 

[denturist-student]

thanks for the tips...i will order dr. massads videos.

 

[denturist-student]

I am wondering if he would allow me to participate in his hands on courses.

 

[kcdt]

I am wondering if he would allow me to participate in his hands on courses.

I would definitely ask.

 

[Irosemal]

we are in office and start with alginate and use a heavy body lab putty for the bite if there is not existing dentures. at final try in, we do a pvs wash in the try in.If there are existing dentures,we simply do a pvs inside existing with a blue bite between. then pour,mount, and index while patient waits.(about 45 min).much prefer latter to former.haven't done occlusion rims for 15 yr at least!

My office is doing a wash impression per my instructions and not having patients occlude/close down . They hold it in the mouth with their hands the whole time ... I’m saying this will yield very bad results ! But they argue it’s fine