Chapter 14: Throat & Oral Cavity

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Hello and welcome back to the Deep Dive.

We are shifting gears a bit today.

Usually we're tackling these broad concepts or big historical trends, but today we are zooming in.

Literally zooming in.

Literally.

We are getting very, very granular.

We are taking a single chapter from a cornerstone medical text chapter 14 of Bates' Guide to Physical Examination and History -Taking, and we are just going to tear it apart.

That's right.

And for those of you who might be hearing chapter 14 and thinking, wow, that sounds a little dry, let me just say this is the chapter on the throat and oral cavity.

And if you are in the clinical world at all, a med student, nursing student, PA, anyone, or honestly even if you just want to understand how a doctor actually thinks when they say open wide, this is absolutely foundational.

Exactly.

Our mission today is to take this static two -dimensional text and really turn it into a dynamic audio guide.

Yeah, bring it to life.

We want to walk you, the learner, through the anatomy, the history -taking, the physical exam, all of it.

And we're going to be really rigorous about this.

We are sticking strictly to the Bates text because we know so many of you are using this for your exams, your OSCEs, your boards.

This is meant to be that audio companion you wish you had while you were highlighting the book at two in the morning.

But it's more than just passing a test, right?

We really want to get at the why.

The why.

Why do we care so much about the color of the gums?

Why do we ask the patient to stick their tongue out?

What's the point?

So to the learner,

listening right now, whether you're on your commute to the hospital or,

you Let's get into the mindset.

The mouth is a small space.

It is.

It's dark, it's wet.

And frankly, I think a lot of students just try to get in and get out as fast as they possibly can.

Which is such a mistake.

I mean, as Bates points out right at the beginning, the mouth is a window.

It's a window to systemic health.

Systemic, not just local.

Not just local at all.

You can spot things like anemia, HIV, autoimmune disorders, even neurological issues just by taking a careful look in there.

If you rush it, you're going to miss the story the body is trying to tell you.

Okay, so let's slow down then.

Let's start where any good explorer starts with a map.

We have to understand the geography, the anatomy and physiology before we can even think about diagnosing anything.

Right.

It's a simple rule, but it's everything.

If you don't know what normal looks like, you have absolutely no hope of identifying abnormal.

So we approach the patient,

the very entrance to the oral cavity.

The lips.

Bates describes them as simply muscular folds.

Simple enough, right.

But think about the function.

They surround the entrance to the mouth.

And when you part those muscular folds, you get your first real view of the landscape inside.

The gingiva, the gums and the teeth.

Let's pause on the gums for a second.

I feel like this is an area where students can get confused, especially about color.

We're often taught this simple idea that pink is healthy.

But is that always true?

No, and that's a really crucial point for inclusivity and just for accuracy in your physical diagnosis.

Bates is very, very clear on this.

In people with lighter skin, yes, the gingiva is typically pale or kind of coral pink, and it should be lightly stippled.

Stippled?

What does that mean?

It means it has a texture, kind of like an orange peel.

It's not perfectly smooth.

Okay, so a little bit of texture.

But what about in patients with darker skin?

Right.

So in people with darker skin, the gingiva can be diffusely brown, or it might be partly brown, in patches.

And that's just melanin.

It is completely physiological.

So just to be crystal clear, if a student sees brown patches on the gums of a black patient, their first thought should not be pathology.

Absolutely not.

That is a normal variant.

And mistaking normal physiology for disease, that's a big deal.

It leads to unnecessary anxiety for the patient, unnecessary testing.

And I guess the reverse is true, too.

Exactly.

If you see very, very pale pink gums in a patient who you would expect to have darker pigmentation, now you should be thinking about something else.

You might be looking at anemia.

You have to know the baseline.

And what about the structure?

The gums aren't just a flat line across the teeth, are they?

No.

If you look closely, and you should, the gingival margin, that's the very edge of the gum, it should have this beautiful scalloped shape.

It rides up and down around each tooth.

And between the teeth, you have these little pointed triangles of tissue.

Those are called the interdental papillae.

And why does that specific shape matter so much?

Because when those little points get blunted, or they look swollen and red, or they've started to recede down the tooth, that is your first, earliest sign of periodontal disease.

You're looking for that crisp scalloped edge to be firmly attached to the teeth.

Let's talk about the tissue connecting everything.

If I pull my own upper lip up, I can feel that tight band of tissue right in the middle.

That's the labial frenulum.

It's a mucosal fold.

And its whole job is to connect the lip to the gingiva.

You have one on the top and one on the bottom.

And looking at the tissue just inside the lip, does Bates make a distinction between the different types of skin in there?

It does, yeah.

You have the alveolar mucosa, which is that reddish tissue right next to the gums, and then it merges into the labial mucosa, which is the lining of the lip itself.

Knowing these different zones is actually really helpful because it lets you describe exactly where a lesion is.

So you could be more precise.

Way more precise.

Is it on the lip liner, basically, or is it down by the bone?

Big difference.

Okay, let's move from the soft tissues to the hardware, the teeth.

The teeth.

You know, we often overlook them in general medicine.

We tend to think, oh, that's for the dentists, but that really creates a gap in care.

So what's the basic structure we absolutely need to know?

Well, first, that a tooth isn't just a rock, it's a living structure.

It's made chiefly of dentin.

The root of the tooth sits down in a bony socket.

And the crown, that's the part you can see, is covered in enamel.

And enamel is famously tough.

It's the hardest substance in the human body.

But inside,

that's where the problem is.

Inside is the vulnerability.

There are small blood vessels and nerves that enter the tooth down at the apex of the root, and they pass up into what's called the pulp canal.

Which explains so clearly why a toothache is so visceral.

It's direct nerve pain.

It's direct nerve pain.

And it's also why an infection in there, an abscess, can go septic.

It has a direct highway right into the bloodstream.

Now, I have to be honest with you.

The numbering system, this is something I see students fumble with all the time.

Bates outlines the universal numbering system.

Can you walk us through this so someone listening can actually visualize it without looking at a chart?

I can try.

Okay, so everyone listening, picture the patient's open mouth in front of you.

We are going to count in a big circle.

There are 32 teeth in a full adult set.

We start at the top right.

The patient's top right, not my top right.

Yes.

Crucial distinction.

Always the patient's right.

So the upper right third molar, that's the wisdom tooth way in the back, is number one.

Okay.

Number one, top right corner.

Then you just count across the upper jaw, moving toward the left.

So the upper right central incisor, the big front tooth, is number eight.

The upper left central incisor, right next to it, is number nine.

Okay, so the midline is between eight and nine.

Exactly.

And you just keep going left until you hit the upper left wisdom tooth.

That is number 16.

So just to recap, one through 16 is the entire top arch moving from the patient's right to their left.

You've got it.

Now, here's the tricky part.

Don't switch sides.

You drop straight down from tooth 16.

The lower left wisdom tooth is number 17.

So you don't jump back to the right side, you drop down.

And then you go back across the bottom, you count along the bottom jaw now from left to right.

The lower left central incisor is 24.

The lower right one is 25.

And you finish your journey at the lower right wisdom tooth, which is number 32.

So it's a big clockwise circle if you're looking at the patient.

Yeah.

Start top right, go to top left, drop to bottom left, and finish the bottom right.

But why do we really need to know this?

Can't I just write in my note the back molar on the bottom?

You can, but precision matters so much in medicine.

If you write abscess on tooth number 30, any dentist, any oral surgeon, any ER doc knows exactly which tooth that is, the lower right first molar.

It prevents wrong sight procedures and allows you to track the history of that one specific tooth over years.

That's a fair point.

Okay, let's move inward.

The tongue.

A fascinating organ.

It's what's known as a muscular hydrostat, but for our purposes, we're really looked at the surface.

The top that's called the dorsum is covered in papillae.

That's the rough stuff.

That's the rough stuff, yeah.

These papaya give the tongue its texture.

Some of them look like little red dots, which is perfectly normal, and often there's a thin white coating on the tongue.

Bates notes that this is also normal.

It's usually just some dead cells and food debris.

But if you ask the patient to lift their tongue up, the underside is a totally different landscape.

Completely different.

Ask the patient to touch the tip of their tongue to the roof of their mouth.

The undersurface should be smooth.

There are no papillae there.

It's shiny.

And there's another frenulum there, too.

The lingual frenulum.

It anchors the tongue to the floor of the mouth.

If that's too short, that's what we call tongue tie or ankyloglossia, and it can really affect speech.

Now, if you look at the base of that frenulum,

there are some important structures there, right?

Some ducts.

Yes.

This is a key anatomical landmark that you need to find.

You will see the openings for Wharton's ducts.

These are the ducts for the big submandibular glands.

They pass forward from the glands and open on these little papillae on either side of that lingual frenulum.

And the sublingual glands.

They're right there, too.

They lie just under the mucosa on the floor of the mouth.

They have multiple tiny little ducts that aren't as visible.

But knowing exactly where Wharton's ducts are is so important, because a stone can get lodged right there and cause a ton of swelling and pain.

Okay, let's peer into the darkness.

The pharynx.

The back of the throat.

The architecture here is actually quite beautiful if you look at it closely.

You have this archway.

It's formed by what we call the anterior and posterior pillars.

And the soft palate is basically the roof of that arch.

Correct.

The soft palate ends in the uvula, that little punching bag that hangs down in the middle.

And where do the tonsils fit into this picture?

The tonsils sit in what's called the tonsil or fossa, which is basically the pocket or the cove between those anterior and posterior pillars.

Now, I know I've had moments where I look in an adult's throat and I just, I don't see any tonsils.

Is that a problem?

Should I be worried?

Not at all.

In adults, the tonsils are often small or even completely absent because they atrophy with age.

Or, you know, they might have had them removed as a kid.

Seeing an empty fossa is a very normal variant.

Before we leave the anatomy section, one last place.

The cheeks.

The buccal mucosa.

Yes.

And there is one major landmark here you cannot miss.

You have to find the stenson duct.

This is the parotid gland duct, right?

Right.

The parotid is that large salivary gland in front of the ear.

Its duct opens up on the inside of the cheek.

And Bates gives us a very specific coordinate for it.

It's located on the buccal mucosa near the upper second molar.

Okay, near the upper second molar.

What am I actually looking for?

What does it look like?

It looks like a small papilla.

It's a little bump.

Sometimes if there's inflammation, like with the mumps, it can be red or look like it's pouting.

But usually it's a very subtle little bump.

The main thing is you need to know it's there so you don't mistake it for a polyp or some other kind of lesion.

Okay, so we have our map.

We know the

landmarks.

Now we can start the real investigation, part two.

The interview or the health history.

This is where we put on our detective hats.

The text makes a really, really important point right at the start of the section.

Most symptoms that happen in the mouth represent benign processes.

Right.

Like you bit your cheek or you burned your tongue on hot pizza.

Exactly.

A canker sore.

But occasionally these symptoms can reflect a very serious underlying disease.

And our job in the interview is to filter the signal from the noise, to distinguish the benign from the truly worrisome.

Let's start with the absolute classic complaint.

Doc, I have a sore throat.

Pharyngitis.

It is one of the most common reasons people see a doctor.

And usually it's just part of an acute upper respiratory illness, a URI.

So a virus.

Almost always a virus.

But patients, and to be honest, a lot of doctors, they worry about bacteria,

specifically group A strep.

Because strep needs antibiotics and viruses.

Well, they don't.

Correct.

And that's a huge issue for antibiotic stewardship.

So Bates discusses some clinical prediction rules to help us out.

Specifically, the center criteria.

These are designed to predict the likelihood of having strep or another bacteria, fusobacterium necrophorum.

Okay, so walk us through those criteria.

What are they?

There are four key signs you're looking for in the history and on the exam.

One, a history of fever.

Two, tonsillar exudates.

That's the white pus you can see on the tonsils.

Three,

swollen, tender anterior cervical adenopathy.

So sore lymph nodes in the front of the neck.

And four, the absence of a cough.

I want to stop on that last one.

Absence of cough.

Why does not coughing make you think of bacteria?

That seems a little counterintuitive.

It's all a matter of probability.

If you are coughing, sneezing, and you have a runny nose, that whole constellation of symptoms is almost certainly a viral syndrome that's affecting your entire respiratory tract.

Strep, on the other hand, tends to be a very localized hit right to the throat.

So no cough actually equals a higher risk of strep.

Okay, so if I have a patient with a fever, puts on their tonsils, swollen nodes, and no cough, I can say for sure they have strep.

Well, hold on a second.

This is where the clinical nuance really comes in.

Bates includes a very significant caveat here.

The sensitivity and the specificity of these rules are actually less than 90%.

Less than 90%.

So there's a pretty decent margin of error.

There is.

If you rely only on the symptoms, you will end up prescribing antibiotics to a lot of people who don't actually need them.

And that's just bad stewardship.

So what's the current recommendation then?

What are we supposed to do?

The guidelines now suggest using these criteria to decide who you should test.

Don't just treat based on the symptoms.

Use a rapid antigen test or a throat culture to confirm the diagnosis first.

So the history guides the test, and then the test guides the treatment.

That is the modern approach, exactly.

What about bleeding gums?

What should we ask about that?

So most often it's just gingivitis.

It's a local problem.

But you have to broaden your scope.

You have to ask about bleeding elsewhere.

Do you find that you bruise easily?

Do you get a lot of nose bleeds?

So you're thinking about platelet disorders or maybe even something like leukemia.

Right.

Because if the gums are bleeding and they have petechia all over their legs, that's a hematologic emergency.

That's not a dental issue you can send them home with.

Okay, next symptom, hoarseness.

This feels like a big one.

Hoarseness is a huge one, and it's defined as any change in the voice quality.

It can be husky, rough, harsh, or maybe lower pitched than usual.

The acute causes seem pretty obvious.

You know, shouting at a concert, getting a cold, viral laryngitis.

But Bates has a very specific rule here.

It does.

It's the two -week rule, and it's simple.

If hoarseness lasts for over two weeks, you must refer that patient for a laryngoscopy.

Wait two weeks?

What's the magic number there?

Because simple, acute inflammation should have resolved by then.

If it persists beyond two weeks, you have to start considering chronic or structural causes.

It could be something as simple as acid reflux irritating the vocal cords, or vocal cord nodules from voiceover use, or polyps.

Or something worse.

Or something much worse, head and neck cancers.

Or even a thyroid mass that's pressing on the recurrent laryngeal nerve, which controls the vocal cords.

The text also mentions neurologic disorders.

How does a raspy voice connect to, say, the nervous system?

Well, think about it.

Phonation, making sound, requires incredibly precise muscle control.

Diseases like Perkinson's, ALS, or myasthenia gravis can all present with a soft, breathy, or harsh voice, because the motor neurons that are supposed to be controlling those vocal cords are starting to fail.

Wow, that's fascinating.

So the voice is actually a part of the motor exam?

In a way, yes.

A very important way.

Okay, one last history item.

Helitosis.

Bad breath.

Yeah, it's an uncomfortable kavik to bring up, but it's a necessary one.

You just have to ask nicely.

Have you happened to notice any changes in your breath lately?

And what are we trying to find out with that question?

Usually the cause is oral.

You know, poor hygiene, smoking, plaque buildup, gum disease.

But it can be a sign of something systemic.

Sinusitis can do it.

Tonsillitis.

Even abscesses in the lungs can cause a really foul breath.

And the text mentions some rare metabolic causes, too.

It does, yeah.

These are more like textbook cases, but they're important.

Uncontrolled diabetes can give a fruity, acetone -like breath.

That's ketoacidosis.

Liver cirrhosis has a very distinct musty smell.

There's even a genetic condition called

trimethylaminaria, which is known as fish odor syndrome.

But, you know, 99 % of the time, you should start by looking at the teeth and the tongue.

Okay, so we've done the interview.

We've gathered our clues.

Now it's time for part three.

The physical exam.

Inspection and pet patient.

Right.

And before you even touch the patient, you need two things.

First,

good lighting.

I can't stress this enough.

You cannot examine a mouth in a shadow.

Use a pen light.

Use the light on your otoscope, whatever you have.

And the second thing.

If the patient wears dentures, they must come out.

I feel like a lot of students feel awkward about that.

Asking an elderly patient to take their teeth out.

It can definitely feel awkward, but you have to do it.

You can offer them a paper towel or a cup.

Be very respectful.

But you have to explain why.

You can say, I need to check the skin underneath your dentures to make sure everything is healthy.

You absolutely cannot see ulcers, stomatitis, or even early cancers if they're covered up by a big plastic plate.

It's like trying to inspect a floor without lifting up the rug.

That's a perfect analogy.

Okay, so dentures are out.

Light is on.

We start with the lips.

We inspect them for color, for moisture, any lumps, ulcers, cracking.

And Bates has a really useful table of specific lip lesions.

Table 14 -1 that we should probably break down.

Let's do it.

First up, angular chylitis.

Okay, so this presents as a softening of the skin right at the angles, the corners of the mouth.

And that softening is then followed by fissuring or cracking.

What causes that?

Is it just like chapped lips?

It can be a nutritional deficiency like riboflavin or iron.

But very often it's actually mechanical.

It's caused by something called overclosure.

If a patient has no teeth or they have poorly fitting dentures, their jaw overcloses.

This makes the corners of their mouth fold inward.

And saliva just pools there.

Exactly.

The saliva macerates the skin.

It makes it soggy and broken down.

And that creates the perfect warm, wet environment for Candida, which is yeast, to grow.

So it's a mechanical problem that leads to a fungal infection.

That is so interesting.

Okay, what about actinic chylitis?

So actinic always refers to the sun.

This is a result of excessive sunlight exposure.

And it usually affects the lower lip because that's the one that catches all the light.

The lip starts to lose its normal redness.

It becomes scaly, thickened, and it might even look slightly averted or turned out.

And why do we care about that one?

Because it is a precursor to squamous cell carcinoma.

It is precancerous.

You have to take it seriously.

Then there is swelling, angioedema.

This is a diffuse, non -pitting, tense swelling of the dermis and the subcutaneous tissue.

And the key is that it develops very rapidly.

Is it always an allergy?

Not always.

And that's an important distinction.

It can be allergic, which is triggered by mast cells and histamine.

And that's usually associated with hives and itching.

But it can also be bradykin and mediated.

That's the type we see with ACE inhibitors, right?

Like Lisinopril.

Correct.

And that type usually does not ditch.

But here's the critical part.

Both types can be life -threatening if the swelling involves the larynx and blocks the airway.

Okay, one more lip lesion from the table.

The chancre.

This is the primary lesion of syphilis.

It usually appears about three to six weeks after the initial infection.

And it looks like an ulcerated papule, but the key feature is an indurated or hard edge.

Is it painful?

No.

And that's the dangerous part.

It is typically painless.

A patient might just think it's a weird cold sore that won't go away and ignore it, but it is incredibly infectious.

So if you see a painless ulcer with a hard edge on the lip.

You glove up immediately.

You do not touch that lesion with your bare hands.

Okay.

Moving inside the mouth,

the oral mucosa.

You need a tongue blade for this.

You have to retract the cheeks.

And you're inspecting for any white patches, nodules, or ulcers.

And Bates really emphasizes palpation here.

Yes.

Inspection is not enough.

If you see a lesion that looks suspicious, you have to feel it.

You are feeling for induration, any thickening or hardness.

Cancer feels hard.

Simple inflammation usually feels soft or kind of boggy.

Let's hit the specific findings for the mucosa.

First, the incredibly common canker sore.

The athos ulcer.

We've all had them.

It's a painful, shallow, whitish gray oval ulcer.

And it has this characteristic red halo around it.

It heals in seven to 10 days.

Totally benign.

Okay.

Let's contrast that with coplic spots.

Coplic spots are an early sign of measles.

They look like small white specks that resemble grains of salt on a very red background.

Grains of salt on a red background.

That sounds like a classic board question description.

It absolutely is.

And you usually find them on the buccal mucosa near the first and second molars.

What about Fordyce spots?

Totally normal.

They're just sebaceous glands that got misplaced during development.

They appear as small yellowish spots on the mucosa.

You can tell the patient not to worry about them.

The tick, yeah.

Small red spots.

In the mouth, they're often just caused by accidentally biting your cheek.

But if you see a lot of them and there's no history of trauma, you have to think about infection or, more seriously,

low platelets.

And finally, leukoplakia.

This is a term we hear a lot and I think it's often misunderstood.

Yeah, leukoplakia just means white patch.

Specifically, it's a thickened white patch that can occur anywhere on the oral mucosa.

Is it cancer?

Not necessarily.

It's often a benign reactive process, maybe from the irritation of chewing tobacco or a rough tooth.

But, and this is a big but, it can lead to cancer.

So the rule is simple.

If you find a white patch that you can't scrape off and you can't identify it as something else, it requires a biopsy.

Period.

Okay, moving on to part four.

Examining the gums and teeth.

We're back at the gingiva.

And we're looking again for that redness and swelling that suggests gingivitis.

Bates mentions a black line on the gums.

That sounds ominous.

Yeah, that can be a sign of lead poisoning.

It's rare now, but it's a very distinctive finding if you see it.

Let's go back to the tables.

Table 14 -3 has some specific gum abnormalities.

Right, so we already covered marginal gingivitis, the red swollen margins, the blunted papillae.

But there's a much more severe form,

acute necrotizing ulcerative gingivitis.

The acronym for that is A -N -U -G.

Yes, and historically it was called trench mouth because it was common in soldiers in World War I.

This is a sudden, very painful condition that comes with fever and malaise.

The interdental papillae actually develop ulcers.

A grayish pseudo membrane forms over them.

And the breath is described as foul.

Wow, that sounds incredibly painful.

It is.

It's a very aggressive infection that spreads along the gum tissue.

What about the opposite problem when the gums grow too much?

Gingival hyperplasia.

This is where the gums enlarge and grow into these heaped up masses.

In severe cases, they can even cover the teeth entirely.

And why does that happen?

Well, simple information can do it, but often it's medication induced.

Finnytoin, which is a seizure medication, is the classic cause.

But you also see it with cyclosporine and calcium channel blockers.

And some systemic conditions like leukemia or even just pregnancy can cause it.

Speaking of pregnancy, there's a specific lesion called a pregnancy tumor.

The pyogenic granuloma.

It's a bit of a misnomer, though.

It's not a true tumor and it's not pyogenic, meaning it doesn't produce pus.

It's really just a rapid proliferation of blood vessels.

What does it look like?

It's a red or purple papule, usually on the gums.

It's soft, it's painless, but it bleeds very, very easily.

It happens in about one to five percent of pregnancies.

And it usually resolves on its own after the baby is born.

Let's turn our attention to the teeth themselves.

Bates does a great job helping us distinguish between the different types of wear and tear.

Attrition versus erosion versus abrasion.

Yeah, this is great for doing some Sherlock Holmes style deduction.

OK, so what's attrition?

Attrition is the wearing down of the chewing surfaces just from repetitive use.

Basically, it's an effect of aging.

The enamel wears off over time, exposing the yellowish -brown dentin underneath.

And erosion.

Erosion is chemical destruction.

From acid.

Exactly.

And the pattern tells you the source.

If you see erosion of the enamel on the back of the front teeth, the lingual surface, you have to think about bulimia from recurrent vomiting or severe acid reflux.

And abrasion.

Abrasion is trauma from holding foreign objects in your mouth.

The text mentions things like holding nails or bobby pins between your teeth.

Or even just really aggressive tooth brushing.

It leaves these characteristic notches in the teeth, usually right at the gum line.

And one final one.

Hutchinson teeth.

This is a pathognomonic sign of congenital syphilis.

The permanent incisors are smaller than normal.

They're widely spaced.

And they have these notches on their biting surfaces.

They kind of look like the tip of a screwdriver.

Okay, part five.

The tongue and floor of mouth.

Now, to me, this feels like the most critical part of the entire exam.

At least for life -saving detection.

I completely agree.

This is the oral cancer screening protocol.

But first, let's just check the function.

The nerve test.

Right.

You ask the patient to stick their tongue straight out.

This is a test of cranial nerve 12, the hypoglossal nerve.

And what am I looking for?

You're looking for symmetry.

If the nerve is damaged on one side, say the right side, the muscles on that side are paralyzed or weak.

So the strong, healthy muscles on the left side will push the tongue over.

So which way does it end up pointing?

It points toward the lesion.

It points to the weak side because the healthy side overpowers it.

The classic mnemonic is the tongue licks the wound.

I like that.

Okay, got it.

Now, let's talk about the cancer screen itself.

So men over 50, smokers, and heavy alcohol users are the traditional high -risk group.

But really, you should be screening everyone.

And what is the proper technique?

You can't just ask them to say, ah, and expect to see a tongue cancer.

No, you won't.

Squamous cell carcinomas love to hide on the sides, the lateral margins, or at the very base of the tongue.

And to see those areas, you have to physically move the tongue.

How do you do that?

So with your gloves on, you take a piece of gauze.

You gently grasp the tip of the patient's tongue.

Then you pull it over to the patient's left.

This nicely exposes the entire right lateral margin.

You inspect it carefully.

Then, and this is the part people forget, you palpate it.

Why is palpation so important?

Because an early cancer might just feel like a firm knot or a thickened area long before it looks like a big scary ulcer.

You are feeling for induration.

Then you reverse the process and do the other side.

While we're looking at the tongue, there are some benign conditions that can look really scary but actually aren't.

Geographic tongue is a classic example.

It literally looks like a map on the tongue.

These smooth red areas that are denuded of papillae surrounded by these raised white borders.

The pattern can even change over time.

It's completely benign.

What about hairy tongue?

That one is visually disturbing, but it's also benign.

The papillae on the tongue become elongated and they can trap debris or bacteria.

They can look yellow, brown, or even black.

It's often associated with antibiotic use or poor oral hygiene.

But we have to be careful to distinguish hairy tongue from hairy leukoplakia.

Yes, that is a critical distinction.

Hairy leukoplakia is very different.

These are whitish raised plaques that are found on the sides of the tongue.

They have this kind of feathery or corrugated pattern.

And can you scrape them off?

No, you cannot.

And that's one way you can distinguish them from thrush.

Hairy leukoplakia is a finding that is strongly associated with HIV and AIDS.

It's caused by the Epstein -Barr virus becoming reactivated in an immunocompromised person.

And thrush, just to be complete.

Thrush is candidiasis.

It's a thick white coating that looks a bit like cottage cheese.

It can be scraped off, but when you do, it leaves a raw red bleeding surface underneath.

It's also seen in immunosuppression or after using steroid inhalers.

Okay, let's move to part six.

The pharynx and the roof of the mouth.

So you look up at the hard palate, and you might see this bony growth right in the middle.

That is a Taurus palatinus.

Does that sound as scary as it is?

Not at all.

It's completely benign.

It's just an extra growth of bone.

Unless it's so large that it interferes with fitting dentures, you can just ignore it.

But if you look at the palate and you see deep purple lesions.

That's Kaposi sarcoma.

Yes, a classic finding associated with AIDS.

Okay, now the soft palate, the uh test.

This is testing a different nerve, right?

This is cranial nerve 10, the vagus nerve.

So what's supposed to happen when the patient says uh?

The soft palate should rise symmetrically, lifting the uvulus straight up in the midline.

The whole point of this is to close off the nasopharynx so that food and drink don't go up your nose when you swallow.

And what if the nerve is paralyzed on one side?

If the nerve is paralyzed, say on the left side, the palate on that paralyzed side fails to rise.

The healthy side, the right side pulls upward and essentially drags the uvula toward itself.

So the uvula deviates away from the side with the lesion?

Correct, it's the perfect way to remember it.

The tongue points toward the wound, the uvula points away.

Finally, let's look at the tonsils and the pharynx itself.

Here we're looking for signs of inflammation.

Exidative tonsillitis, those white patches of pus, that's highly suggestive of strep or mono.

Pharyngitis is just diffuse redness without any exudates.

And there's a rare but important one mentioned, diphtheria.

Diphtheria is very rare now because of vaccines, but it's deadly.

It presents with a dull red throat and this characteristic gray exudate, its pseudo membrane, that can cover the uvula and the pharynx.

The danger is that it can swell and obstruct the airway.

Okay, we've completed the exam.

We have probed, palpated, and inspected everything.

Now for part seven, documentation and health promotion.

That's right, if you don't document it, you didn't do it.

So give us the shorthand.

What does a normal exam look like written down in the chart?

For the head, you might see NCECT, which just means normocephalic atraumatic.

For the mouth itself, you might write something like oral mucosa, pink and moist, dentition and good repair, tongue midline, tonsils absent, pharynx without erythema or exudates.

And if it's abnormal?

Then you have to be specific.

Pharynx is erythematous.

Bilateral tonsillar hypertrophy noted with white exudates.

Tender anterior cervical lymphadenopathy is present.

And you have to describe the nodes.

Yes, their size, their tenderness, whether they're mobile or fixed.

Let's wrap this all up by talking about health promotion.

Why should the learner listening care about this beyond just passing their exam?

Because the public health data is just staggering.

I mean, Bates notes that 19 % of children and 91 % of adults have untreated caries, cavities.

91 % of adults, that's an incredible number.

It's huge.

And periodontal disease, gum disease, affects nearly 50 % of adults over the age of 30.

And this isn't just about your teeth falling out.

This is a state of chronic inflammation.

It's been linked to diabetes, to heart disease, to adverse pregnancy outcomes.

And certain risk factors really matter here.

They do.

Low income, smoking, diabetes,

and medications.

We mentioned xerostomia dry mouth earlier.

Hundreds of common medications cause it.

And if you don't have enough saliva, you lose your mouth's natural washing mechanism and your risk for decay just skyrockets.

And finally, let's talk about oral cancer.

Tobacco and alcohol still account for about 75 % of cases.

But there is a massive, massive shift happening in the epidemiology of this disease.

You're talking about the HPV connection.

Exactly.

The human papillomavirus specifically strains 16.

It is now responsible for about 70 % of all oropharyngeal cancers in the United States.

And that completely changes the typical patient, doesn't it?

It completely changes the demographic.

It used to be the older man who was a heavy smoker and drinker.

Now we are seeing younger men, people in their 40s and 50s who are nonsmokers, developing these cancers of the tonsils and the base of the tongue.

And the risk factors are different.

The risk factors are different.

It's the number of sexual partners engaging in oral sex behaviors.

So given this shift, should we be screening everyone for this?

Well, that's the debate.

The USPSTS, the US Preventive Services Task Force, finds insufficient evidence to recommend routine screening of asymptomatic adults.

But the American Dental Association has a different take, they say.

If you see a suspicious lesion or if a patient has persistent symptoms,

refer them to a specialist immediately.

Don't wait.

So vigilance is still the key.

Always.

OK, let's try to unpack all of this.

We have covered everything from the numbering of the teeth to the deviation of the uvula.

We certainly have.

What's the big overarching takeaway for you when you think about this chapter?

For me, it's that the mouth is just so communicative.

It really speaks for the rest of the body.

When you look at the gums, you are literally seeing the patient's blood status.

You can see signs of anemia or platelet disorders.

When you look at the tongue, you are seeing the nervous system with cranial nerve 12, and you're seeing the immune system with things like hairy leukoplakia.

It's not just a hole for food.

No, not at all.

It's a diagnostic dashboard if you know how to read it.

And I think here's a provocative thought to leave our listeners with.

We just talked about how HPV is changing the face of oral cancer.

So if the patient in front of you doesn't look like the classic case, if they are 30 years old, they're fit, they're a nonsmoker,

do we still have the clinical discipline to do a thorough, careful exam?

Or do we subconsciously skip that part because they look healthy?

And that bias, that's exactly what leads to misdiagnoses.

The disease is changing, so our exam skills have to stay just as sharp, if not sharper.

A huge thank you to the Last Minute Lecture Team for putting this deep dive together.

We really hope this helps you master Chapter 14.

Keep learning.

And more importantly, keep looking.

We'll see you next time.