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<v Speaker 1>You know, usually when we talk about a dental treatment,

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<v Speaker 1>there is this underlying expectation of precision. It feels well,

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<v Speaker 1>almost like engineering.

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<v Speaker 2>Right, Yeah, like building a bridge or something exactly.

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<v Speaker 1>You prip a tooth for a crown, you take a

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<v Speaker 1>digital scan, the lab makes the ceramic and it fits

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<v Speaker 1>onto this totally solid static foundation. It's measurable.

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<v Speaker 2>It is. I mean, you're generally working with hard, unyielding

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<v Speaker 2>tissues enamel, dentin or maybe implants anchored rigidly in bone.

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<v Speaker 2>The variables are for the most part, highly controlled.

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<v Speaker 1>But then you step into the world of complete dentures

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<v Speaker 1>and suddenly that solid foundation is just completely gone.

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<v Speaker 2>Oh entirely.

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<v Speaker 1>We're looking at a clinical landscape that is entirely dynamic.

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<v Speaker 1>It moves, it yields, it literally changes shape from morning tonight.

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<v Speaker 1>And because of that, I think so many general dental

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<v Speaker 1>practitioners view complete dentures as honestly a bit of a

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<v Speaker 1>black art.

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<v Speaker 2>Yeah, they really do. You're trying to build a static

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<v Speaker 2>prosthesis on a moving target. It is the app sleute

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<v Speaker 2>definition of clinical muddy waters. But it is a rigorous science,

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<v Speaker 2>not a dark art. The biology and the physics dictate everything,

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<v Speaker 2>and once you understand those mechanisms that unpredictability just sort

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<v Speaker 2>of fades away.

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<v Speaker 1>Which is exactly what we are here to map out today.

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<v Speaker 1>So welcome to this deep dive. Whether you are a

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<v Speaker 1>dental student prepping for your final boards, a young professional

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<v Speaker 1>looking to refine your clinical skills, and you know, stop

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<v Speaker 1>fearing a dentalist patience, or just a really curious self

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<v Speaker 1>learner fascinated by oral biomechanics. We are going to demystify

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<v Speaker 1>this entire process today.

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<v Speaker 2>Absolutely.

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<v Speaker 1>We're unpacking Complete Dentures, a clinical manual for the general

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<v Speaker 1>dental practitioner by doctor Hugh Devlin, and our mission today

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<v Speaker 1>is to break down this manual in vivid scientific detail.

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<v Speaker 1>We're going from the very first time you evaluate the

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<v Speaker 1>patient's mouth all away to troubleshooting and home care.

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<v Speaker 2>And I'd argue the urgency of mastering these specific technique

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<v Speaker 2>is actually.

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<v Speaker 1>Climbing really, even with all our modern preventative stuff.

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<v Speaker 2>Yeah, you might look at the incredible advancement in preventative

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<v Speaker 2>dental health and assume that complete dentures are just this

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<v Speaker 2>relic of the past, but the demographics tell a completely

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<v Speaker 2>different story. People are living much much longer, oh right,

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<v Speaker 2>we're seeing a dramatic global increase in centenarians. And because

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<v Speaker 2>of this, the patients who do eventually lose all their teeth, well,

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<v Speaker 2>they're becoming identalists much later in life.

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<v Speaker 1>So the clinical profile of the average denture patient is

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<v Speaker 1>shifting older. What does that actually change for the practitioner

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<v Speaker 1>sitting chair side?

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<v Speaker 2>It changes the entire biological baseline your identialist patients. They

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<v Speaker 2>present with highly complex medical backgrounds, polypharmacy, severe anatomical resorption.

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<v Speaker 2>But the biggest hurdle, honestly is their neuromuscular adaptability.

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<v Speaker 1>Because it's a huge piece of foreign plastic in their mouth.

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<v Speaker 2>Exactly, a sixty year old might have the neurological plasticity

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<v Speaker 2>to intuitively train their tongue in cheeks to hold that

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<v Speaker 2>plastic in place while chewing, But an eighty five year

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<v Speaker 2>old patient, their ability to subconsciously learn those new muscle

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<v Speaker 2>patterns is severely reduced. You can't just hand them a

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<v Speaker 2>generic piece of acrylic and expect their failing adaptability to

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<v Speaker 2>just figure it out. Yeah, you have to actively engineer

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<v Speaker 2>the denture to work in perfect harmony with whatever muscle

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<v Speaker 2>control they have left.

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<v Speaker 1>Wow, Okay, let's start with that initial evaluation then, because

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<v Speaker 1>clearly before you even think about mixing alginate or heating

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<v Speaker 1>up impression compound, you have to understand the biological canvas

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<v Speaker 1>you're building on. We really do so extrarely. We're looking

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<v Speaker 1>at facial symmetry, muscle tone, and interraclusal clearance, which is

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<v Speaker 1>that freeway space between the jaws at rest and then intrallly.

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<v Speaker 1>We are palpating the ridge shape, checking for prominent bony

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<v Speaker 1>toy that will act as full crumbs and rock the denture,

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<v Speaker 1>and of course locating muscle attachments.

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<v Speaker 2>Those muscle attachments are so critical. Take the mentalist muscle

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<v Speaker 2>in the lower anterior mandible for example. Okay, if the

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<v Speaker 2>residual alveolar ridge has resorbed severely, the insertion of that

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<v Speaker 2>mentalis muscle might sit almost at the very crest of

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<v Speaker 2>the remaining bone.

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<v Speaker 1>Oh wow, so right where the denture sits exactly.

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<v Speaker 2>So every single time the patient moves their lower lip,

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<v Speaker 2>that muscle fires and it will physically eject a lower

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<v Speaker 2>denture right out of place.

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<v Speaker 1>Okay, let's unpack this because the manual also red flags

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<v Speaker 1>a massive issue regarding the patient's medical history. It specifically

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<v Speaker 1>highlights anticholinergic drugs, So things like older anahistamines, cyclic antidepressants,

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<v Speaker 1>or overactive bladder medication.

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<v Speaker 2>Yeah, this is a perfect example of a systemic medication

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<v Speaker 2>just destroying a mechanical dental treatment. Anycholinergic drugs block the

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<v Speaker 2>neurotransmitter acetocholine in the nervous.

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<v Speaker 1>System, And how does that specifically sabotage our denture.

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<v Speaker 2>Well, the parasympathetic nervous system relies on acetocullin to stimulate

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<v Speaker 2>the salivary glands, particularly for producing that thin, watery, seedyal saliva.

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<v Speaker 2>When you block those receptors, the glands basically stop pumping.

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<v Speaker 1>Oh, so they get dry mouth.

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<v Speaker 2>Profound zerostomia. And a complete dentro relies entirely on a thin,

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<v Speaker 2>can tinuous film of saliva between the acrylic and the

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<v Speaker 2>ucosa those It creates the capillary attraction and the peripheral seal. Right,

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<v Speaker 2>without that fluid dynamic, the mechanical retention fails completely.

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<v Speaker 1>I always visualize it like trying to stick a rubber

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<v Speaker 1>suction cup to a bone dry window. Yes, I mean,

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<v Speaker 1>you can push as hard as you want and the

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<v Speaker 1>sheet might be a perfect match, But without that microscopic

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<v Speaker 1>layer of moisture to create the fluid seal. It's just

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<v Speaker 1>going to fall right off.

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<v Speaker 2>That is a very accurate visualization. And while we are

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<v Speaker 2>evaluating that soft tissue environment, we also have to assess

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<v Speaker 2>for denture stomatitis. It's incredibly common, actually affecting up to

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<v Speaker 2>sixty five percent of venture wearers in some population.

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<v Speaker 1>That is huge. And the manual breaks this down using

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<v Speaker 1>Newton's three types to categorize the severity, right it does.

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<v Speaker 2>Type I is localized hyperamia, basically pinpoint redness, usually caused

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<v Speaker 2>by a direct mechanical trauma from a high spot on

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<v Speaker 2>the denture.

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<v Speaker 1>Look a blister from a tight share exactly.

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<v Speaker 2>Then Tach two is a generalized aerathema that's a bright

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<v Speaker 2>red swollen area covering the entire denture bearing mucosa. And

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<v Speaker 2>finally Type three is inflammatory peppillary hyperplasia, where the tissue

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<v Speaker 2>actually becomes nodular and bumpy. It often looks like a

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<v Speaker 2>cobblestone street. Yet Ty three frequently requires surgical removal before

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<v Speaker 2>a new denture can even be fabricated.

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<v Speaker 1>Now, when we hear dentrostomatitis, I feel like the immediate

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<v Speaker 1>assumption is a fungal infection, specifically candied ALBICNS. But the

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<v Speaker 1>manual highlights this fascinating paradox about how this yeast actually

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<v Speaker 1>behaves in the mouth. It doesn't behave like a traditional

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<v Speaker 1>tissue infection at all.

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<v Speaker 2>No, it doesn't. Candid ALBUCNS rarely invades the mucosal tissue itself.

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<v Speaker 2>In these cases. If you biopsy that bright red and

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<v Speaker 2>flamed palate, you generally won't see fungal hyphae penetrating into

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<v Speaker 2>the patient's epithelia.

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<v Speaker 1>Wait really, yeah.

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<v Speaker 2>Instead, the yeast is actually thriving inside the microscopic pores

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<v Speaker 2>and undercuts of the acrylic denture itself. The plastic is

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<v Speaker 2>the incubator.

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<v Speaker 1>Wait. Wait, if the fungus is living in highly inside

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<v Speaker 1>the plastic of the denture, why is the patient's mucosal

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<v Speaker 1>tissue turning bright red and inflamed? I mean, is it

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<v Speaker 1>an allergic reaction to the east.

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<v Speaker 2>It's a severe inflammatory response. These colonies metabolize and multiply

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<v Speaker 2>in the acrylic, right, and they pump out metabolic by

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<v Speaker 2>products toxins and enzyme oh. I see, so these toxins

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<v Speaker 2>leech out of the plastic and just bathe the adjacent tissue.

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<v Speaker 2>The patient's mucosa is reacting to this constant toxic chemical

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<v Speaker 2>assault sitting pressed against their palate. The fungal load is

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<v Speaker 2>massively higher on the plastic than on the patient.

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<v Speaker 1>So if a practitioner just prescribes an anti fungal lozenge

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<v Speaker 1>for the patient to suck on and sends them home,

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<v Speaker 1>they are completely missing the target totally.

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<v Speaker 2>They are treating the symptom, not the reservoir. As soon

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<v Speaker 2>as the patient stops the lozenges, the toxins from the

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<v Speaker 2>denture will just inflame the tissue all over again.

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<v Speaker 1>So what's the fix?

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<v Speaker 2>The clinical protocol here must be twofold. First, you have

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<v Speaker 2>to disinfect the prosthesis. The manual recommends an overnight soak

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<v Speaker 2>in a zero point two percent for hexiting solution or

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<v Speaker 2>a very dilute household bleach.

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<v Speaker 1>Solution, although quick tavia. You have to ensure the denture

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<v Speaker 1>doesn't have a metal framework or a soft silicone liner,

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<v Speaker 1>because bleach would just rapidly degrade those exactly good point.

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<v Speaker 2>And second, you have to correct the physical trauma. Poorly

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<v Speaker 2>fitting dentures rub the tissue, creating an inflammatory, protein.

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<v Speaker 1>Rich exoity, and that exodate is basically a buffet for

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<v Speaker 1>the candida, just feeding the colony exactly. So to stop

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<v Speaker 1>the rubbing, you often have to fix a severely worn

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<v Speaker 1>occlusal scheme. The book provides this brilliant Chercide intervention for this.

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<v Speaker 1>If the posterior plastic teeth have worn completely flat over

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<v Speaker 1>the years, the patient's jaw will basically slide around uncontrollably

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<v Speaker 1>during chewing right.

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<v Speaker 2>Which drags the denture base across.

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<v Speaker 1>The tissue exactly. So you can temporarily fix this by

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<v Speaker 1>adding two to three millimeters of self curing acrylic directly

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<v Speaker 1>to the lower molars to re establish a stable bite.

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<v Speaker 2>But you have to tightly control the vertical dimension of

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<v Speaker 2>the jaw while that new acrylic cures. You can't just

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<v Speaker 2>slap we acrylic on the teeth and tell the patient

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<v Speaker 2>to bite down blindly, because.

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<v Speaker 1>They'll just slide into the wrong position.

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<v Speaker 2>Right, They'll overclose or bite to the side, and then

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<v Speaker 2>you created an even worse problem.

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<v Speaker 1>So the technique is to take warm, moldable impression compound,

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<v Speaker 1>place it just on the canines and second molars, and

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<v Speaker 1>physically guide the patient's jaw to close at the correct

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<v Speaker 1>vertical height. Once that compound cools. It acts as a

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<v Speaker 1>hard physical vertical stop. Then you apply the doughe self

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<v Speaker 1>curing acrylic to the remaining posterior teeth, coat the opposing

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<v Speaker 1>upper teeth and petroleum jelly so they don't accidentally glue together,

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<v Speaker 1>and just guide the patient to bite down until they

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<v Speaker 1>firmly hit those compound stops. It literally stabilizes the moving target.

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<v Speaker 2>It does, and only once that tissue is healthy and stable,

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<v Speaker 2>can you move to the next phase, which is recording

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<v Speaker 2>the anatomical landscape. And this requires a really deep understanding

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<v Speaker 2>of tissue.

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<v Speaker 1>Physics because, like we established, the mouth is not a

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<v Speaker 1>static block of plaster. It yields to press sure and

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<v Speaker 1>if this tissue acts like a fluid under pressure, I

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<v Speaker 1>imagine taking an accurate impression is an absolute nightmare.

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<v Speaker 2>It can be.

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<v Speaker 1>I mean, if you just shove an alginate looted tray

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<v Speaker 1>in there, won't you capture the tissue in a completely distorted,

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<v Speaker 1>compressed state. How do you record a shape that's constantly

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<v Speaker 1>changing based on how hard you push?

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<v Speaker 2>Well, you have to understand that oral mucosa is visco elastic.

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<v Speaker 2>It possesses both fluid and solid properties. When a patient

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<v Speaker 2>bites down, or when you press an impression tray into

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<v Speaker 2>the tissue, there is this immediate elastic displacement. The solid

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<v Speaker 2>components compress right but if you maintain that pressure for

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<v Speaker 2>just a few seconds, you enter a slower phase called creep.

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<v Speaker 1>Creep, like the tissue is slowly flown away from the pressure.

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<v Speaker 2>Exactly, interstitial tissue, fluid and blood are physically being squeezed

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<v Speaker 2>out of the vascular beds and extracellular spaces in that

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<v Speaker 2>specific area. Wow, when you release the load, the tissue

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<v Speaker 2>springs back elastically right away, but that delayed creep recovery

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<v Speaker 2>the fluid slowly seeping back into the area that can

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<v Speaker 2>take hour.

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<v Speaker 1>And to complicate things, the tissue isn't uniform. The muco

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<v Speaker 1>periostium sitting directly on the crest of the bony ridge

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<v Speaker 1>is tightly bound down so it barely yields. But if

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<v Speaker 1>you move back to the posts dam area at the

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<v Speaker 1>junction of the hard and soft palate, you have highly

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<v Speaker 1>compressible submucosa filled with fatty and glandular tissue exactly.

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<v Speaker 2>And because of this chaotic dynamic tissue bed dentistry develop

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<v Speaker 2>different philosophies for taking impressions. Let's look at the extremes first.

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<v Speaker 2>On one end, you have the mucostatic approach okay, eucostatic,

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<v Speaker 2>which means capturing the tissue entirely at rest with zero

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<v Speaker 2>fluid displacement. You use a very runny, low viscosity material

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<v Speaker 2>like a fluid alginate or plaster of Paris, and a

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<v Speaker 2>tray spaced well off the tissues so no pressure, absolutely

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<v Speaker 2>minimal pressure. The resulting denture fits the resting tissues beautifully,

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<v Speaker 2>but the.

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<v Speaker 1>Moment the patient tries to chew a piece of steak,

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<v Speaker 1>the denture rocks because the rigid acrylic hits the hard,

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<v Speaker 1>unyielding bony areas first, while the compressible tissues just give way.

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<v Speaker 2>Correct. So on the other end of the spectrum you

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<v Speaker 2>have the mucocompressive technique. Here you intentionally force the tissue

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<v Speaker 2>into that compressed creep state using a highly viscous material

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<v Speaker 2>like heavy impression.

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<v Speaker 1>Compound, so you're pushing hard.

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<v Speaker 2>You apply significant seating pressure. The resulting denture fits perfectly

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<v Speaker 2>when the patient is biting down with maximum force.

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<v Speaker 1>Wait here's where it gets really interesting. If you process

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<v Speaker 1>a denture to fit the tissues only when they are

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<v Speaker 1>fully compressed and squeezed a fluid. What happens when the

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<v Speaker 1>patient stops chewing and relaxes. Won't that delayed creep recovery happen?

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<v Speaker 2>Oh, you know it.

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<v Speaker 1>The tissues will slowly fill back up with fluid, attempt

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<v Speaker 1>to rebound to their arresting shape, and literally pop the

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<v Speaker 1>denture right off the ridge.

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<v Speaker 2>You've just described the exact mechanical failure of a purely

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<v Speaker 2>mucocompressive technique. The rebounding tissue acts like a slow motion

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<v Speaker 2>ejector seat.

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<v Speaker 1>That is wild.

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<v Speaker 2>Therefore, the clinical gold standard is the selective mucok impressive technique.

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<v Speaker 2>You design a custom impression tray that selectively applies pressure

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<v Speaker 2>to the primary stress bearing areas like the buckle shelf

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<v Speaker 2>in the mandible, which can handle the load while physically

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<v Speaker 2>relieving the tray over the areas that cannot handle pressure,

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<v Speaker 2>like the incisive papilla.

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<v Speaker 1>And nowhere is the selective pressure more critical than when

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<v Speaker 1>dealing with a fibrous or flabby anterior ridge. This happens

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<v Speaker 1>when the underlying bone has resorbed, leaving behind a wobbly

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00:13:27.480 --> 00:13:30.320
<v Speaker 1>flap of connective tissue. It's like trying to take a

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00:13:30.360 --> 00:13:32.639
<v Speaker 1>precise mold of a wet sponge sitting on top of

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<v Speaker 1>a rock.

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<v Speaker 2>That's a great way to picture it.

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<v Speaker 1>If you press the sponge, it folds over. If you

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<v Speaker 1>process a hard dentsure with that tissue folded over, the

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<v Speaker 1>patient will be an agonizing pain.

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<v Speaker 2>Yeah, And the manual provides an incredibly elegant engineering solution

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<v Speaker 2>to this biological problem. It's called the window tray technique.

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<v Speaker 2>You take a preliminary impression and cast a model. On

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<v Speaker 2>that model, you construct a custom rigid acrylic tray. Okay,

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<v Speaker 2>but before you go to the mouth, you take an

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<v Speaker 2>acrylic burr and physically cut a large window completely out

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<v Speaker 2>of the tray, directly over the exact area of the

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<v Speaker 2>flabby tissue.

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<v Speaker 1>So you have a standard tray, but with a literal

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<v Speaker 1>hole exposing the wobbly bits.

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<v Speaker 2>Yes. First you border mold the edges of the tray

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00:14:13.559 --> 00:14:16.559
<v Speaker 2>to capture the muscle attachments. Then you load the intact

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00:14:16.639 --> 00:14:19.399
<v Speaker 2>parts of the tray with a medium viscosity material like

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00:14:19.519 --> 00:14:22.600
<v Speaker 2>zinc oxide eugenoal paste and set it. You are capturing

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00:14:22.639 --> 00:14:26.080
<v Speaker 2>all the firm, healthy tissues under a controlled functional load

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00:14:27.000 --> 00:14:31.000
<v Speaker 2>the paste sets. Meanwhile, that flabby tissue is just sitting

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<v Speaker 2>there perfectly at rest, sticking out through the window. You cut.

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<v Speaker 1>Ah, I see where this is going.

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<v Speaker 2>Finally, you take a very thin, watery wash of plaster

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00:14:39.480 --> 00:14:42.799
<v Speaker 2>of Paris and you carefully paint it over that exposed

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00:14:42.960 --> 00:14:47.200
<v Speaker 2>flabby tissue zero pressure. You capture the firm tissue under

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00:14:47.240 --> 00:14:50.759
<v Speaker 2>load and the flabby tissue at absolute resting state, all

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00:14:50.759 --> 00:14:52.039
<v Speaker 2>in the exact same impression.

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00:14:52.200 --> 00:14:55.320
<v Speaker 1>It's just brilliant. Okay, So we have conquered the visco

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00:14:55.360 --> 00:14:58.639
<v Speaker 1>elastic tissue and captured the perfect landscape. Now we need

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00:14:58.679 --> 00:15:01.200
<v Speaker 1>to figure out exactly where the upper and lower jaws

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00:15:01.360 --> 00:15:04.120
<v Speaker 1>sit in three D space relative to each other, so

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00:15:04.200 --> 00:15:06.200
<v Speaker 1>we can position the teeth, which.

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00:15:06.039 --> 00:15:09.519
<v Speaker 2>Brings us to the absolute golden rule of complete denture occlusion.

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00:15:09.679 --> 00:15:12.720
<v Speaker 2>Drum roll please, the intercustable position, which is the position

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00:15:12.759 --> 00:15:15.879
<v Speaker 2>where the artificial upper and lower teeth interlock maximally, it

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00:15:15.960 --> 00:15:18.600
<v Speaker 2>must perfectly coincide with a retruated contact.

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00:15:18.279 --> 00:15:21.840
<v Speaker 1>Position, the retruited contact position or RCP. That's a joint

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00:15:21.840 --> 00:15:24.879
<v Speaker 1>guided position, right. It's when the condoles of the mandible

300
00:15:25.320 --> 00:15:29.159
<v Speaker 1>are in their most superior, posterior, reproducible position in the

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00:15:29.159 --> 00:15:30.879
<v Speaker 1>glenoid fossa.

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00:15:30.320 --> 00:15:33.559
<v Speaker 2>Precisely now, In a young patient with natural teeth, their

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00:15:33.600 --> 00:15:36.960
<v Speaker 2>habitual chewing bite might actually sit slightly forward of RCP.

304
00:15:37.720 --> 00:15:41.360
<v Speaker 2>Their brain uses proprioception from the ligaments around their tooth

305
00:15:41.360 --> 00:15:44.720
<v Speaker 2>throats to guide the jaw into that forward position.

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00:15:44.600 --> 00:15:47.159
<v Speaker 1>But in complete dentures there are no tooth roots.

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00:15:47.240 --> 00:15:49.919
<v Speaker 2>Right. If you don't build the artificial bite in RCP,

308
00:15:50.440 --> 00:15:54.759
<v Speaker 2>the dentures will fail. The patient's dentialist jaw will naturally

309
00:15:54.799 --> 00:15:58.840
<v Speaker 2>seek that stable retruded joint position during swallowing and resting.

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00:15:58.960 --> 00:15:59.440
<v Speaker 1>Makes sense.

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00:15:59.519 --> 00:16:02.200
<v Speaker 2>If the art official teeth don't interlock perfectly in that

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00:16:02.279 --> 00:16:06.480
<v Speaker 2>exact retruited position, the cusps will crash together on their inclines.

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00:16:07.120 --> 00:16:10.679
<v Speaker 2>That creates lateral forces that violently dislodge the denture basis.

314
00:16:10.879 --> 00:16:14.039
<v Speaker 1>So to map out this spatial relationship, we use wax

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00:16:14.240 --> 00:16:17.639
<v Speaker 1>rim bite blocks. The manual gives us some hard numbers

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00:16:17.639 --> 00:16:20.759
<v Speaker 1>to start shaping these rims. It suggests the upper wax

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00:16:20.840 --> 00:16:23.639
<v Speaker 1>room should be about ten millimeters high in the anterior

318
00:16:23.679 --> 00:16:26.679
<v Speaker 1>maxilla and the lower rim should be about five millimeters

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00:16:26.799 --> 00:16:30.720
<v Speaker 1>high in the posterior mandible. We use these rims to

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00:16:30.840 --> 00:16:34.960
<v Speaker 1>establish the freeway space the introclusal clearance, which should be

321
00:16:35.039 --> 00:16:38.039
<v Speaker 1>about two to four millimeters when the patient's jaw muscles

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00:16:38.080 --> 00:16:41.559
<v Speaker 1>are totally relaxed. But I have to challenge these static numbers.

323
00:16:42.039 --> 00:16:45.960
<v Speaker 1>Does a strict ten milimeter anterior height really apply to everyone?

324
00:16:46.039 --> 00:16:48.519
<v Speaker 1>Good question? I mean, what if you have a patient

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00:16:48.519 --> 00:16:52.440
<v Speaker 1>with a severe skeletal discrepancy or a patient whose maxilla

326
00:16:52.480 --> 00:16:55.960
<v Speaker 1>has suffered extreme bone resorption over forty years? Do these

327
00:16:56.000 --> 00:16:58.080
<v Speaker 1>textbook averages just go out the window?

328
00:16:58.600 --> 00:17:02.600
<v Speaker 2>Does a crucial critical distinction. Those numbers are starting points.

329
00:17:02.600 --> 00:17:05.359
<v Speaker 2>They're not biological laws. They just provide a statistical average

330
00:17:05.359 --> 00:17:07.920
<v Speaker 2>to give the lab a baseline. But you must radically

331
00:17:08.000 --> 00:17:11.279
<v Speaker 2>alter them chair side based on facial esthetics and phonetic function.

332
00:17:11.759 --> 00:17:15.319
<v Speaker 2>For instance, to get the occlusal plane right, use a

333
00:17:15.359 --> 00:17:18.880
<v Speaker 2>fox byte plane to align the upper wax rim so

334
00:17:18.960 --> 00:17:22.279
<v Speaker 2>it is perfectly parallel with the interpupillary line, the line

335
00:17:22.279 --> 00:17:25.759
<v Speaker 2>between the patient's eyes, and also the all ur tragal

336
00:17:25.799 --> 00:17:26.799
<v Speaker 2>line on the side of the face.

337
00:17:26.920 --> 00:17:29.160
<v Speaker 1>Right, and you are looking at the horizontal projection two.

338
00:17:29.880 --> 00:17:33.759
<v Speaker 1>The labial surface of the upper central incisors typically sits

339
00:17:33.799 --> 00:17:36.680
<v Speaker 1>about eight to ten millimeters anterior to the center of

340
00:17:36.720 --> 00:17:40.799
<v Speaker 1>the incisive papilla. The manual also dives into the Golden

341
00:17:40.880 --> 00:17:44.319
<v Speaker 1>ratio of one point six one point eight. When assessing

342
00:17:44.319 --> 00:17:46.680
<v Speaker 1>the vertical dimension of the face, you are comparing the

343
00:17:46.680 --> 00:17:49.599
<v Speaker 1>distance from the pupil to the lip commissure against the

344
00:17:49.640 --> 00:17:52.359
<v Speaker 1>distance from the lip to the bottom of the chin. Exactly,

345
00:17:52.599 --> 00:17:55.079
<v Speaker 1>if you blindly follow a ten milimeter rule on a

346
00:17:55.119 --> 00:17:59.240
<v Speaker 1>severely resorbed patient, you might severely overclose their bite.

347
00:18:00.079 --> 00:18:04.240
<v Speaker 2>Uure has disastrous esthetic consequences. It visually mimics an angles

348
00:18:04.240 --> 00:18:06.079
<v Speaker 2>class three maleeclusion.

349
00:18:05.559 --> 00:18:07.039
<v Speaker 1>Right the underbyte look yeah.

350
00:18:07.079 --> 00:18:09.799
<v Speaker 2>If the bite is too short, the lower jaw hinges

351
00:18:09.839 --> 00:18:13.799
<v Speaker 2>too far upward and forward, the chin becomes excessively prominent,

352
00:18:14.119 --> 00:18:17.000
<v Speaker 2>the corners of the mouth turned down, and the lips

353
00:18:17.079 --> 00:18:21.400
<v Speaker 2>basically collapse inward. It can instantly age a patient's face

354
00:18:21.440 --> 00:18:22.240
<v Speaker 2>by twenty.

355
00:18:22.000 --> 00:18:25.000
<v Speaker 1>Years, which proves why determining where to put the teeth

356
00:18:25.079 --> 00:18:28.720
<v Speaker 1>visually is just so vital. But the manual pushes us

357
00:18:28.759 --> 00:18:32.319
<v Speaker 1>to go beyond static anatomical landmarks and actually look at

358
00:18:32.440 --> 00:18:36.839
<v Speaker 1>dynamic muscle forces. The mouth is essentially this narrow corridor

359
00:18:36.880 --> 00:18:38.400
<v Speaker 1>of competing muscular forces.

360
00:18:38.440 --> 00:18:39.000
<v Speaker 2>It really is.

361
00:18:39.119 --> 00:18:42.480
<v Speaker 1>The tongue is constantly pushing outward while the lips and

362
00:18:42.519 --> 00:18:46.039
<v Speaker 1>the bascinator muscles and the cheeks are constantly pushing inward.

363
00:18:45.880 --> 00:18:48.079
<v Speaker 2>Right, and if you set the artificial teeth outside of

364
00:18:48.079 --> 00:18:51.279
<v Speaker 2>the balance point between those forces, the muscles will constantly

365
00:18:51.319 --> 00:18:55.079
<v Speaker 2>dislodge the denture. This balance point is called the neutral zone,

366
00:18:55.319 --> 00:18:57.759
<v Speaker 2>and to capture it we use a functional impression technique

367
00:18:57.960 --> 00:18:58.799
<v Speaker 2>called the piece of gram.

368
00:18:59.119 --> 00:19:01.799
<v Speaker 1>I absolutely love the mechanics of this technique. Instead of

369
00:19:01.799 --> 00:19:04.559
<v Speaker 1>guessing where the teeth should go, you let the patient's

370
00:19:04.559 --> 00:19:06.759
<v Speaker 1>own musculature physically carve out the boundary.

371
00:19:06.880 --> 00:19:07.599
<v Speaker 2>It's so smart.

372
00:19:07.680 --> 00:19:10.640
<v Speaker 1>You take a rigid lower base plate and attach these

373
00:19:10.680 --> 00:19:13.319
<v Speaker 1>little wire loops sticking up from the ridge. Then you

374
00:19:13.400 --> 00:19:17.599
<v Speaker 1>load those loops with a thick, moldable silicone putty. You

375
00:19:17.640 --> 00:19:19.880
<v Speaker 1>place it in the patient's mouth and ask them to

376
00:19:19.880 --> 00:19:25.200
<v Speaker 1>perform normal, exaggerated functions. So they speak, swallow, purse, their lips,

377
00:19:25.400 --> 00:19:26.640
<v Speaker 1>smile widely.

378
00:19:26.400 --> 00:19:29.400
<v Speaker 2>And as they perform those ashens, the strong muscles of

379
00:19:29.440 --> 00:19:31.279
<v Speaker 2>the tongue on the lingle side and the lips and

380
00:19:31.359 --> 00:19:34.759
<v Speaker 2>cheeks on the buckle side, they forcefully mold that soft

381
00:19:34.799 --> 00:19:37.400
<v Speaker 2>puddy wow. They compress it and shape it into a

382
00:19:37.519 --> 00:19:41.640
<v Speaker 2>unique patient specific corridor where the inward and outward muscular

383
00:19:41.680 --> 00:19:43.759
<v Speaker 2>forces are perfectly neutralized.

384
00:19:43.839 --> 00:19:46.559
<v Speaker 1>So once that putty sets, you take it out, and

385
00:19:46.599 --> 00:19:49.119
<v Speaker 1>you have a physical three D model of the denture space.

386
00:19:49.519 --> 00:19:51.839
<v Speaker 1>You cast a plaster index around it, hand it to

387
00:19:51.839 --> 00:19:54.839
<v Speaker 1>the lab technician and tell them the artificial teeth must

388
00:19:54.839 --> 00:19:57.640
<v Speaker 1>fit exactly inside this specific envelope.

389
00:19:57.720 --> 00:20:01.400
<v Speaker 2>Yes, exactly. If you place a lower just two millimeters

390
00:20:01.480 --> 00:20:04.240
<v Speaker 2>too far lingually outside that zone, the side of the

391
00:20:04.279 --> 00:20:07.079
<v Speaker 2>tongue will catch it during speech and constantly lift the denture.

392
00:20:07.319 --> 00:20:11.559
<v Speaker 1>It completely removes the guesswork. Now, once the lab has

393
00:20:11.559 --> 00:20:14.359
<v Speaker 1>set the teeth and wax based on our piesagram, we

394
00:20:14.440 --> 00:20:18.680
<v Speaker 1>reach the final processing phase. To translate that delicate three

395
00:20:18.720 --> 00:20:24.599
<v Speaker 1>D wax relationship into hardocrylic properly, we have to utilize articulators.

396
00:20:24.960 --> 00:20:28.079
<v Speaker 2>We do, and the manual strongly advises that whether you

397
00:20:28.160 --> 00:20:32.119
<v Speaker 2>use a simple average value articulator or a semi adjustable one,

398
00:20:32.400 --> 00:20:34.359
<v Speaker 2>you really must use a facebo transfer.

399
00:20:34.480 --> 00:20:37.200
<v Speaker 1>Okay, So, a face bow looks a bit intimidating, like

400
00:20:37.279 --> 00:20:40.799
<v Speaker 1>a giant metal caliber wrapping around the patient's face, but

401
00:20:41.079 --> 00:20:44.359
<v Speaker 1>its biomechanical purpose is simple, right. It records the exact

402
00:20:44.480 --> 00:20:47.319
<v Speaker 1>three D spatial relationship of the patient's upper jaw to

403
00:20:47.359 --> 00:20:51.359
<v Speaker 1>their temporal mandibular joints. Hinge axis, and then it transfers

404
00:20:51.359 --> 00:20:54.039
<v Speaker 1>that exact geometry to the hinges of the articulator on

405
00:20:54.079 --> 00:20:55.319
<v Speaker 1>the lab bench exactly.

406
00:20:55.799 --> 00:20:58.039
<v Speaker 2>Without a faceco transfer, the radius of the arc of

407
00:20:58.079 --> 00:21:00.440
<v Speaker 2>closure on the articulator will not match the radius of

408
00:21:00.480 --> 00:21:02.880
<v Speaker 2>the arc of closure in the patient's actual skull, which

409
00:21:02.920 --> 00:21:05.240
<v Speaker 2>means the lab might get the teeth to interlock perfectly

410
00:21:05.279 --> 00:21:07.279
<v Speaker 2>on the metal hinges, but the moment you put the

411
00:21:07.359 --> 00:21:10.279
<v Speaker 2>denture in the patient's mouth, their jaw closes on a

412
00:21:10.319 --> 00:21:13.160
<v Speaker 2>slightly different geometric arc and the teeth will crash into

413
00:21:13.160 --> 00:21:14.200
<v Speaker 2>each other prematurely.

414
00:21:14.519 --> 00:21:16.640
<v Speaker 1>Right, But let's say you do use a face bow,

415
00:21:16.880 --> 00:21:19.599
<v Speaker 1>You do a wax try in, and it's perfect. The

416
00:21:19.680 --> 00:21:22.880
<v Speaker 1>problem is acrylic resin is a plastic. When the lab

417
00:21:22.960 --> 00:21:27.039
<v Speaker 1>boils it, polymerizes it and cools it, it shrinks, it warps.

418
00:21:27.160 --> 00:21:31.880
<v Speaker 1>Always tiny microscopic dimensional shifts happen during curing. So how

419
00:21:31.920 --> 00:21:34.440
<v Speaker 1>do we fix those processing errors before the patient ever

420
00:21:34.480 --> 00:21:35.599
<v Speaker 1>even sees the denture.

421
00:21:36.200 --> 00:21:39.640
<v Speaker 2>You anticipate the shrinkage. You use a split cast mounting technique.

422
00:21:39.880 --> 00:21:43.480
<v Speaker 2>Before the lab processes the denture, they cut indexing notches

423
00:21:43.519 --> 00:21:46.079
<v Speaker 2>into the base of the plaster cast. Okay, after the

424
00:21:46.119 --> 00:21:49.759
<v Speaker 2>acrylic is fully cured. They take the unbroken cast, complete

425
00:21:49.799 --> 00:21:52.119
<v Speaker 2>with the newly processed denture, and they snap it right

426
00:21:52.200 --> 00:21:55.559
<v Speaker 2>back onto the articulator, using those notches to guarantee its

427
00:21:55.599 --> 00:21:56.359
<v Speaker 2>original position.

428
00:21:56.519 --> 00:21:59.680
<v Speaker 1>And then you check the bite again, and inevitably, because

429
00:21:59.680 --> 00:22:02.200
<v Speaker 1>of the crylic frinkage, a cusp is hitting too hard,

430
00:22:02.720 --> 00:22:04.880
<v Speaker 1>which brings us to one of the most critical clinical

431
00:22:04.920 --> 00:22:09.119
<v Speaker 1>and ammonics in dentistry, the bul rule for selective grinding.

432
00:22:09.480 --> 00:22:12.599
<v Speaker 2>The Boule rule is just essential for achieving balanced articulation

433
00:22:12.720 --> 00:22:16.200
<v Speaker 2>during lateral excursions. When the patient grinds their jaw to

434
00:22:16.240 --> 00:22:19.839
<v Speaker 2>the side, you want even gliding contact if you have

435
00:22:19.839 --> 00:22:22.839
<v Speaker 2>a premature heavy contact on the working side during that slide,

436
00:22:23.039 --> 00:22:25.119
<v Speaker 2>you don't just take a burr and randomly grind down

437
00:22:25.119 --> 00:22:26.839
<v Speaker 2>the cusps until it clears.

438
00:22:27.079 --> 00:22:30.480
<v Speaker 1>Let's picture this biomechanically. Why can't we just grind whatever

439
00:22:30.599 --> 00:22:31.440
<v Speaker 1>is hitting.

440
00:22:31.480 --> 00:22:34.440
<v Speaker 2>Because you have to protect the vertical dimension the centric

441
00:22:34.480 --> 00:22:36.839
<v Speaker 2>holding cusps, which are the palatal cusps of the upper

442
00:22:36.880 --> 00:22:40.000
<v Speaker 2>teeth and the buckle cusps of the lower teeth. They

443
00:22:40.039 --> 00:22:43.720
<v Speaker 2>are what physically maintain the patient's vertical bite height when

444
00:22:43.720 --> 00:22:46.960
<v Speaker 2>they're biting straight down in centric occlusion. Oh, I see

445
00:22:47.000 --> 00:22:49.160
<v Speaker 2>if you grind away those holding cusps. To fix a

446
00:22:49.240 --> 00:22:53.400
<v Speaker 2>sideway's sliding interference, you destroy the vertical stops, the whole

447
00:22:53.440 --> 00:22:56.599
<v Speaker 2>byte collapses and the patient overcloses, So you.

448
00:22:56.680 --> 00:23:00.599
<v Speaker 1>Only adjust the non holding cusps. During lateral excursion. The

449
00:23:00.640 --> 00:23:04.319
<v Speaker 1>be Ol rule bet L you grind the buckle cusps

450
00:23:04.359 --> 00:23:06.720
<v Speaker 1>of the upper teeth and the lingual cusps of the

451
00:23:06.759 --> 00:23:10.880
<v Speaker 1>lower teeth. By restricting your burr to those specific cusps,

452
00:23:11.440 --> 00:23:15.319
<v Speaker 1>you eliminate the sideways interference without destroying the vertical stops

453
00:23:15.319 --> 00:23:16.960
<v Speaker 1>that hold the bite open exactly.

454
00:23:17.039 --> 00:23:20.799
<v Speaker 2>It preserves the architecture. Now assume we deliver the adjusted

455
00:23:20.880 --> 00:23:24.680
<v Speaker 2>denture a week later. At the review appointment, the tissue

456
00:23:24.720 --> 00:23:27.920
<v Speaker 2>looks good, but the patient is having trouble speaking clearly,

457
00:23:28.519 --> 00:23:31.400
<v Speaker 2>you have to troubleshoot the phonetics based on the specific

458
00:23:31.480 --> 00:23:34.720
<v Speaker 2>sounds they are struggling with, Like what if they can't

459
00:23:34.720 --> 00:23:38.640
<v Speaker 2>pronounce T or D sounds cleanly? It is almost always

460
00:23:38.680 --> 00:23:42.720
<v Speaker 2>an issue with the anterior horizontal placement. The teeth might

461
00:23:42.759 --> 00:23:45.960
<v Speaker 2>be set too far forward or backward, meaning the tip

462
00:23:45.960 --> 00:23:47.799
<v Speaker 2>of the tongue is hitting the plastic at the wrong

463
00:23:47.839 --> 00:23:50.359
<v Speaker 2>point in space during those explosive consonants.

464
00:23:50.480 --> 00:23:52.839
<v Speaker 1>What if they develop a severe lisp like they are

465
00:23:52.839 --> 00:23:56.400
<v Speaker 1>struggling with S sounds and it sounds like whistling or slushy. Error.

466
00:23:56.599 --> 00:23:59.319
<v Speaker 2>That usually points to the palatolocrylic meaning too thick just

467
00:23:59.359 --> 00:24:02.720
<v Speaker 2>behind the upper central incisors. When you make an S sound,

468
00:24:02.759 --> 00:24:05.799
<v Speaker 2>your tongue forms a very narrow groove channel down the

469
00:24:05.839 --> 00:24:09.119
<v Speaker 2>midline to accelerate air. If the acrylic is too bulky

470
00:24:09.160 --> 00:24:13.799
<v Speaker 2>in that specific spot, it physically obliterates that medial tongue groove.

471
00:24:14.440 --> 00:24:16.400
<v Speaker 2>The air scatters, causing the list.

472
00:24:16.319 --> 00:24:17.359
<v Speaker 1>That makes total sense.

473
00:24:17.480 --> 00:24:20.240
<v Speaker 2>A great clinical trick is to paint a thin layer

474
00:24:20.279 --> 00:24:23.599
<v Speaker 2>of pressure indicating paste on the pallet. Have the patient

475
00:24:23.680 --> 00:24:27.240
<v Speaker 2>loudly say Mississippi several times, and then just look at

476
00:24:27.279 --> 00:24:29.960
<v Speaker 2>the paste. You will see exactly where the tongue is

477
00:24:30.000 --> 00:24:33.039
<v Speaker 2>wiping away the paste, showing you precisely where you need

478
00:24:33.079 --> 00:24:34.119
<v Speaker 2>to thin out the acrylic.

479
00:24:34.400 --> 00:24:37.200
<v Speaker 1>That is incredibly practical. All right, As we wrap up,

480
00:24:37.240 --> 00:24:40.359
<v Speaker 1>we have to look at patients who simply cannot tolerate

481
00:24:40.440 --> 00:24:44.160
<v Speaker 1>this entire conventional process. What happens when your patient is

482
00:24:44.240 --> 00:24:48.079
<v Speaker 1>ninety two years old, physically frail and suffering from dementia.

483
00:24:47.680 --> 00:24:49.720
<v Speaker 2>Or Parkinson's, it's tough.

484
00:24:49.880 --> 00:24:53.160
<v Speaker 1>Their neuromuscular system has spent twenty years learning to control

485
00:24:53.240 --> 00:24:55.960
<v Speaker 1>their current worn out dentures. If you hand them a

486
00:24:56.039 --> 00:25:00.519
<v Speaker 1>denture with a completely new shape, their brain simply cannot adapt.

487
00:25:00.799 --> 00:25:03.400
<v Speaker 2>For these patients, you utilize the template or a copy

488
00:25:03.480 --> 00:25:08.119
<v Speaker 2>denture technique. For a frail patient with reduced adaptability, changing

489
00:25:08.160 --> 00:25:10.559
<v Speaker 2>the shape of the polished surface the contours their tongue

490
00:25:10.559 --> 00:25:13.240
<v Speaker 2>and cheeks have memorized is a disastrous You want to

491
00:25:13.279 --> 00:25:16.200
<v Speaker 2>give them a new fitting surface to improve retention, and

492
00:25:16.319 --> 00:25:19.640
<v Speaker 2>new sharp teeth to improve chewing, but you must maintain

493
00:25:19.799 --> 00:25:24.039
<v Speaker 2>the exact same overall volumetric shape they're used to.

494
00:25:24.720 --> 00:25:27.359
<v Speaker 1>I always compare this to restoring a classic car for

495
00:25:27.400 --> 00:25:28.279
<v Speaker 1>an elderly driver.

496
00:25:28.559 --> 00:25:29.240
<v Speaker 2>Oh, I like that.

497
00:25:29.319 --> 00:25:31.920
<v Speaker 1>If you take their nineteen sixty five Mustang and you

498
00:25:32.039 --> 00:25:34.920
<v Speaker 1>change the steering ratio, move the pedals two inches to

499
00:25:34.960 --> 00:25:37.039
<v Speaker 1>the left, and swap the seat for a bucket seat,

500
00:25:37.200 --> 00:25:39.000
<v Speaker 1>they will crash it. They won't know how to drive it.

501
00:25:39.359 --> 00:25:41.160
<v Speaker 1>But if you just rebuild the engine and put on

502
00:25:41.200 --> 00:25:43.680
<v Speaker 1>new tires while keeping the steering wheel in the seat

503
00:25:43.720 --> 00:25:46.559
<v Speaker 1>exactly where their muscle memory expects them to be, it

504
00:25:46.720 --> 00:25:49.000
<v Speaker 1>still feels like their car. It just runs better.

505
00:25:49.319 --> 00:25:52.920
<v Speaker 2>That's a very apt analogy. The protocol here respects that

506
00:25:53.039 --> 00:25:56.440
<v Speaker 2>muscle memory. You take their old denture and in case,

507
00:25:56.480 --> 00:26:00.000
<v Speaker 2>the entire thing in laboratory silicone putty in a specialized flat.

508
00:26:00.599 --> 00:26:03.519
<v Speaker 2>Once it sets, you pull the old denture out, so

509
00:26:03.640 --> 00:26:06.920
<v Speaker 2>you have a mold exactly. You now have a perfect

510
00:26:07.200 --> 00:26:10.359
<v Speaker 2>hollow three D mold of their existing denture. You pour

511
00:26:10.440 --> 00:26:12.720
<v Speaker 2>melted wax into the space where the teeth go, and

512
00:26:12.759 --> 00:26:15.559
<v Speaker 2>then pour fluid itself carrying acrylic into the space where

513
00:26:15.559 --> 00:26:16.200
<v Speaker 2>the base goes.

514
00:26:16.440 --> 00:26:20.119
<v Speaker 1>So you pull out a perfect physical replica wax teeth

515
00:26:20.160 --> 00:26:21.160
<v Speaker 1>on an acrylic base.

516
00:26:21.359 --> 00:26:24.960
<v Speaker 2>Yes, you use that replica as your custom impression tray

517
00:26:25.200 --> 00:26:27.519
<v Speaker 2>to get a new wash of the tissue, and you

518
00:26:27.599 --> 00:26:30.640
<v Speaker 2>use it as your byte block to record the jaw relationship.

519
00:26:31.039 --> 00:26:33.720
<v Speaker 2>You send it to the lab and the technician literally

520
00:26:33.759 --> 00:26:36.880
<v Speaker 2>plucks out the wax teeth one by one, replacing them

521
00:26:36.880 --> 00:26:38.000
<v Speaker 2>with hard acrylic teeth.

522
00:26:38.160 --> 00:26:38.960
<v Speaker 1>That's amazing.

523
00:26:39.039 --> 00:26:42.319
<v Speaker 2>Patient gets a brain new denture, but the spatial footprint

524
00:26:42.480 --> 00:26:44.160
<v Speaker 2>feels identical to their old one.

525
00:26:44.240 --> 00:26:47.440
<v Speaker 1>The manual also provides some rapid fire tips for emergency,

526
00:26:47.480 --> 00:26:51.519
<v Speaker 1>domicillary or at home care. If a denture fractures cleanly

527
00:26:51.599 --> 00:26:54.519
<v Speaker 1>in two down, the midline. You can carefully superglue it

528
00:26:54.559 --> 00:26:57.960
<v Speaker 1>together with cyanoacrolate, pour a quick plaster cast inside the

529
00:26:58.000 --> 00:27:00.519
<v Speaker 1>fitting surface to hold the shape, widen crack with an

530
00:27:00.519 --> 00:27:03.400
<v Speaker 1>acrylic bur and fill the gap with self curing acrylic

531
00:27:03.480 --> 00:27:07.200
<v Speaker 1>polymerized in a pressurized hydroflask to eliminate porosity.

532
00:27:07.400 --> 00:27:10.559
<v Speaker 2>It also mentions a sobering but vital forensic detail regarding

533
00:27:10.640 --> 00:27:13.720
<v Speaker 2>denture marking. Oh right, If you are inserting an ID

534
00:27:13.880 --> 00:27:16.400
<v Speaker 2>marker into the acrylic to identify a patient in a

535
00:27:16.400 --> 00:27:19.319
<v Speaker 2>worst case scenario like a mass casualty incident or a fire,

536
00:27:19.599 --> 00:27:22.839
<v Speaker 2>paper or allumin tags are completely useless. They will incinerate.

537
00:27:23.160 --> 00:27:24.039
<v Speaker 1>So what do you use?

538
00:27:24.440 --> 00:27:27.440
<v Speaker 2>The ID markers must be made of high grade stainless

539
00:27:27.440 --> 00:27:31.039
<v Speaker 2>deal to survive temperatures exceeding six hundred degrees celsius.

540
00:27:31.319 --> 00:27:34.559
<v Speaker 1>A stark reminder of the broader medical and forensic role

541
00:27:34.960 --> 00:27:38.680
<v Speaker 1>dentistry plays in society. Okay, we have covered a massive

542
00:27:38.680 --> 00:27:42.440
<v Speaker 1>amount of biomechanics from doctor Devlin's manual today. We started

543
00:27:42.440 --> 00:27:46.599
<v Speaker 1>by understanding that dentrostomatitis is often a mechanical trauma problem

544
00:27:46.799 --> 00:27:51.640
<v Speaker 1>exacerbated by candida living in the acrylic reservoir, not the tissue.

545
00:27:51.240 --> 00:27:51.839
<v Speaker 2>We cover a lot.

546
00:27:51.920 --> 00:27:55.839
<v Speaker 1>Yeah, we explored how the viscoelastic creep of mucosa dictates

547
00:27:55.839 --> 00:27:59.240
<v Speaker 1>our selective impression techniques, how we capture the neutral zone

548
00:27:59.240 --> 00:28:02.160
<v Speaker 1>with a piesagram, and how we protect the vertical dimension

549
00:28:02.319 --> 00:28:03.559
<v Speaker 1>using the bul rule.

550
00:28:04.000 --> 00:28:07.799
<v Speaker 2>We've demonstrated that fabricating complete dentures is not a black art.

551
00:28:08.000 --> 00:28:11.400
<v Speaker 2>It requires a rigorous mastery of biologies, spatial mechanics, and

552
00:28:11.440 --> 00:28:16.319
<v Speaker 2>material science, all carefully tailored to the declining neuromuscular adaptability

553
00:28:16.319 --> 00:28:17.519
<v Speaker 2>of the aging patient.

554
00:28:17.480 --> 00:28:20.640
<v Speaker 1>Which brings us to a final provocative thought. As we

555
00:28:20.680 --> 00:28:24.319
<v Speaker 1>look at modern trends in dentistry, the shortened dental arch

556
00:28:24.440 --> 00:28:29.960
<v Speaker 1>concept is becoming increasingly popular. Through advanced periodontics and endodontics,

557
00:28:30.279 --> 00:28:34.119
<v Speaker 1>patients are retaining their front natural teeth much much longer,

558
00:28:34.599 --> 00:28:38.319
<v Speaker 1>even if they lose all their posterior molars in their fifties, which.

559
00:28:38.200 --> 00:28:41.640
<v Speaker 2>Raises a critical physiological question for the future. If a

560
00:28:41.680 --> 00:28:45.400
<v Speaker 2>patient retains just their six lower anterior teeth into their

561
00:28:45.440 --> 00:28:48.200
<v Speaker 2>late eighties or nineties, and then suddenly loses them all

562
00:28:48.240 --> 00:28:51.079
<v Speaker 2>at once due to a medical crisis or a rapid decay,

563
00:28:51.759 --> 00:28:54.599
<v Speaker 2>how will they possibly adapt to a lower complete denture

564
00:28:54.680 --> 00:28:57.400
<v Speaker 2>They won't be able to Their neuromuscular adaptability will be

565
00:28:57.480 --> 00:29:00.400
<v Speaker 2>virtually zero at that extreme age, and they won't have

566
00:29:00.440 --> 00:29:03.559
<v Speaker 2>had the training wheels of waring a partial denture during

567
00:29:03.559 --> 00:29:04.279
<v Speaker 2>their middle age.

568
00:29:04.640 --> 00:29:07.519
<v Speaker 1>It makes you wonder if conventional complete dentures will become

569
00:29:07.559 --> 00:29:11.319
<v Speaker 1>physically impossible for that future generation to tolerate. Will over

570
00:29:11.440 --> 00:29:14.799
<v Speaker 1>dentures where we deliberately perform root canals and retain the

571
00:29:14.880 --> 00:29:17.400
<v Speaker 1>roots of those final teeth beneath the acrylic to provide

572
00:29:17.440 --> 00:29:21.039
<v Speaker 1>bone preservation and physical snapping attention. Will that become the

573
00:29:21.079 --> 00:29:23.799
<v Speaker 1>absolute mandatory baseline standard of care.

574
00:29:24.119 --> 00:29:27.480
<v Speaker 2>It is highly likely. It completely changes the long term,

575
00:29:27.759 --> 00:29:32.000
<v Speaker 2>decades long treatment planning strategy for any general practitioner. You

576
00:29:32.079 --> 00:29:35.240
<v Speaker 2>have to plan for the patient's neurological decline, not just

577
00:29:35.279 --> 00:29:37.039
<v Speaker 2>their dental decline.

578
00:29:37.079 --> 00:29:39.039
<v Speaker 1>All right, before you head into your next clinic session,

579
00:29:39.119 --> 00:29:41.839
<v Speaker 1>Let's do a quick mental review exercise to cement what

580
00:29:41.880 --> 00:29:46.680
<v Speaker 1>we've covered today. Visualize the bul rule in action. Imagine

581
00:29:46.720 --> 00:29:49.759
<v Speaker 1>you have your newly processed dentures mounted on the articulator.

582
00:29:50.319 --> 00:29:53.240
<v Speaker 1>You slide the upper jaw to the right to simulate

583
00:29:53.279 --> 00:29:57.240
<v Speaker 1>a working side lateral excursion. You see a premature heavy

584
00:29:57.279 --> 00:30:00.440
<v Speaker 1>contact on that working side. Based on the biome mechanics,

585
00:30:00.440 --> 00:30:03.599
<v Speaker 1>we discussed which specific cusps on the upper and lower

586
00:30:03.680 --> 00:30:05.799
<v Speaker 1>teeth are you going to adjust with your burr to

587
00:30:05.839 --> 00:30:09.759
<v Speaker 1>clear the interference without collapsing the patient's vertical bite. Map

588
00:30:09.799 --> 00:30:12.480
<v Speaker 1>the cusps out in your head right now, remember.

589
00:30:12.119 --> 00:30:15.279
<v Speaker 2>The preservation of the centric holding cusps. You only adjust

590
00:30:15.279 --> 00:30:17.720
<v Speaker 2>the buckle of the upper and the lingual of the lower.

591
00:30:18.160 --> 00:30:20.200
<v Speaker 1>Thank you for taking this deep dive into the science

592
00:30:20.240 --> 00:30:23.400
<v Speaker 1>of complete ventures with us. Keep questioning the mechanics, keep learning,

593
00:30:23.599 --> 00:30:25.200
<v Speaker 1>and we will see you on the next deep dive.