5. Caries

Caries

A disease, not a symptom. Caries can cause cavities (a hole)

Cavities

hollow places in teeth caused by decay, can be caused by caries or other things

What is usually the cause for caries?

bacteria

What is a huge issue in treating caries?q

accessibility, especially in low income areas

Prevalence

The number or proportion of cases of a particular disease or condition present in a population at a given time. (who HAS caries within a time frame)

Incidence

The number or rate of new cases of a particular condition during a specific time. ( who DEVELOPS caries in a time frame)

Over the years, caries development in the US has been relatively ____

stable

What are factors that contribute to prelevance

regional factors, health systems, economic factors

What are factors that contributed to caries stability around the world?

Improvement and changes around the world on oral health/treatment

Dental caries experience

people who have experienced or had caries in their whole life. Caries experience cannot decrease, only increase (cumulative experience) and varies among diff ethnicities

Which two minority groups have the largest disparity when it comes to caries?

african-american and hispanic

Dental caries

multifactorial, transmissible, infectious oral disease caused primarily by complex interactions of cariogenic oral flora (biofilm) with fermentable dietary carbs on the tooth surface over time. Can be transferred directly (body fluid) or indirectly (sharing a fork)

Vertical transmission

from parent to child

Horizontal trasmission

person to person (partner to partner, friend to friend)

If you have no teeth, can you have caries?

no

Protective factors

saliva flow and components, proteins, antibacterial, fluoride, calcium, phosphate, protective dietary components, n on-cariogenic sweeteners

Pathologic factors

acidogenic bacteria, frequency of fermentable carbs, ingestion, reduced salivary function

acidgenic vs aciduric bacteria

acidgenic= produce the acids that harm enamel

aciduric= survive and thrive in low pH environment

Caries balance consists of

protective factors and pathologic factors

What are the four factors that contribute to caries

teeth, bacteria, diet, time

Cariogenic challenge process

initiated by exposure of the cariogenic bacteria to fermentable carbs such as monosaccharides glucose and fructose or the disaccharides sucrose and lactose

More factors that can lead to caries

Less saliva, eating too much sugar, bacterial imbalance, lack of access to care, oral health literacy

Direct influences on caries/cavities (bacteria/diet)

Good AND bad bacteria

Antibacterial agents

dental sealants

fluoride

chewing gum

saliva

protein

sugars

Ca2+, PO43-

Plaque pH (microbial species)

External influences

education

behavior

sociodemographic status

income

dental insurance coverage

knowledge

oral health literacy

Cariogenic challenge details

1. Initiated by bad bacteria to form

2. Glucose and fructose are small sugars more likely to impact teeth (small, fermentable sugars)

3. Sucrose and lactose are disaccharides, large sugars

Glycolysis

converts glucose into pyruvic acid (via glycolysis) and then pyruvic acid to lactic acid; acetic acid and propionic acids are side products

Through enzymatic rxn, ______ is transferred until it is pyruvate

glucose

Glucans/fructans function

allow caries to stick to the teeth, act as a glue that allows caries to stay on the teeth

Bacteria uses _____ to make lactic acid and other things

glucose and fructose

Stephan Curve

The relationship between pH at the tooth surface and time following consumption of sugar; enamel demineralize @5.5pH; dentin @ 6pH

What raises the ph value

bicarbonate (buffer that stabilizes a low pH higher/normal level. neutralizing agent)

Dentin resorbs _____ than enamel because it has less ______

quicker; minerals

What helps raise Ph to promote remineralization?

bicarbonate and saliva

How long does it take for pH to get back to normal? what is a normal pH? what is critical enamel pH?

50 minutes to an hour

7 is normal

5.5 is critical (can result in demineralization)

Cariogenic shifts the caries balance scale towards

pathologic factors

Enamel

outer surface of the tooth. Mostly made of inorganic materials (crystals). Hydrophobic

more minerals in dentin makes it harder to demineralize

Coke contains a lot of ____ that eats away at the teeth

phosphoric acid

Do enamel and dentin behave the same way? why or why not?

no, they are made up of the same materials but in different compositions

Enamel- 88% inorganic, 10% water, 2% organic

Dentin- 50% inorganic, 30% organic, 20% water

Inactive caries

black caries that do not progress, typically visually unappealing

Location of caries bacteria

Determines where caries will form

Occlusal surfaces- pits/fissures/grooves easily attract caries

Incisors- on palatal surfaces may have pits where caries can develop

Interproximal area between teeth- needs flossing, attracts caries

Plaque stagnation areas

around patient brackets

improper restorations

roots and cervical (gumline)

pits/fissures

interproximal area

Pellicle formation

surface accumulation of growth. Glycoproteins from saliva stick to enamel; bacteria need this layer as primer for attachment

Glycoproteins

form on tooth surface in a matter of minutes through electrostatic forces (negative and positive charges areas)

Pellicle

glycoprotein layer a part of saliva that adheres to tooth surface. bacteria with the right receptor adheres to the pellicle

for biofilm formation, in 0-24 hours, bacteria on tooth...

grows overtime by multiplying in colonies (early attachment bacteria colonizers attach first to help form colonies)

Biofilm formation

co-adhesion and growth of attached bacteria to formation of microcolonies

Do micro colonies vary in bacteria type?

yes

Microbial succession (biofilm formation)

increased species diversity with continued co-adhesion and growth of microcolonies (1-7 days)

- colonies grow thicker, varying forms (long, spiral, ovoid)

- climax community: after 4-7 days

Climax community

one week or older. Big mix of a lot of bacteria, some close to the tooth and some far away

- thicker film and less oxygen on the tooth, more oxygen on plaque surface

- bacteria that need oxygen will stay at the surface

Is the incisal edge a plaque stagnation site?

no

Resident oral flora

resident microflora has a diverse composition, consisting of a wide range of gram positive and gram negative bacterial species, as well as yeasts and other types of microorganisms. This is the NORMAL bacteria (symbiotic relationship)

- when good environment changes (normal pH for example) that is when bad bacteria takes over

Types of resident oral flora

streptococcous salivarious

strep mitis

strep oralis

strep sanguinis

strep dentisani

strep(tovella) melaninogenica

prevotella melaninogenica

fusobacterium nucleatum

veilllonella spp

Resident oral flora benefits

- neutral ph, likes o2

- saturation of microbial attachment sites

- more effective competition for essential nutrients

- the creation of conditions unfavorable to the growth of the invading microbes

- production of inhibitory factors (bacteriocins, hydrogen peroxide)

should the mouth ever be 100% sterile?

no

3 hypothesis to resident oral flora

1. specific plaque

2. non-specific plaque

3. ecological plaque

specific plaque hypothesis

only one bacteria causes one disease (certain bacteria can only cause caries). DEBUNKED

Non-specific plaque hypothesis

more than one bacteria/factor can cause caries, multitude of bacteria. How thick. anaerobic and acidic is the biofilm? enough o2?

Ecological Shift

environmental factors contribute to caries (stress, intaking more sugar). shift in environment cause bacteria type shifts from healthy to bad bacteria causes pH shifts causes caries

Factors of the ecological plaque hypothesis

stress (increased sugar intake and acid production)

low Ph (environmental change)

ecological shift (s. mutans, lactobacilli, bifidobacteria, s. sanguinis and s. gordonii)

Disease (health and caries)

Bacteria most common in early lesions

S mutans

Achinomyces gerensceriae, veillonela parvula, veillonela species

Dentinal caries and tubule infection bacteria

deeper the cavity, the more you find the caries that love acid (acetophillic)

- aciduric can withstand acid conditions (lactic bacilli)

- s mutans

-lactobacillus rhamnosus, acidophilus, paracasei, fermentum, plantanum, casei, johanmei)

-actinomyces israeli, adontolyticus, noeslundi

-bifidobacterium detnum, species

- privatella melaningenica

Root caries bacteria

common on root surfaces, receptors are more compatible with glycoproteins on root surface

- scientists still identifying more

- bifidobacterium are the worst bacteria

(s mutans, actinomyces israeli, actinomyces species, bifidobacterium detium, bifidobacterium breve, bifidbacterium species)

Lesion progression, early stage

bacteria at this stage is not deep in the tooth but is on the surface. easily restorable

- caries begin to etch away at the surface. enamel prisms are etched away superficially and cause pores that go deeper into the enamel

incipient lesions

have not invaded the enamel yet, not always a need for treatment

pseudointact surface layer

(incipient lesions) surface is not broken down, no cavity at this point (darker zone). mineral loss is smallest here

Transluscent zone

has majority of demineralization going into the tooth (review pic)

Lesion body

has the most pores it is why the lesion is weak, Loss of minerals is largest here

4 layers of incipient lesion

pseudointact surface layer, lesion body, dark zone, transluscent zone

what causes lesions to look white?

pores

does cavitation have to be treated?

yes

Lesion progression

- subsurface lesion under pseudointact layer

- increased pore volume (30%)

pores are diffusion path for microorganisms and substrate

- light scattering causes white spot

Dentin contains....

lots of tubules and canals filled with nerve endings from pulpal nerve (why we feel cavities). Nerve endings fuel everything and with acids, they begin to seal/crystallize to heal

Secondary dentin

sclerotic dentin

dentin with plugged up tubulues to protect from further acid/caries advancing (not as a result of aggression). Temp change, stress and chewing can also cause the SD to protect the nerve

Advanced white spot

acids reached dentin and remineralized. When dentin is remineralized, only the collagen fibers remain which makes it softer. Pulpal chambers become smaller and smaller with age from remineralization

White/brown spot

pulp builds tertiary dentin by adding more material to it to make it thicker (result of aggression like caries)

Microcavitation

ICDAS stage 4. More demineralization of dentin, more sclerotic dentin, more tertiary dentin

Cavitation

Dentin exposed and begins to get destroyed

Collagen fibers in tact, minerals removed

MMP enzymes in dentin eat away at collagen fibers caused by acids

destroyed dentin must be drilled and restored

Cavitation

softened collagen network. destroyed dentin has to be removed and restored by filling

Lesion progression into dentin (chart)

REVIEW PIC IN NOTES

infected---affected----sound

zone of destruction if the clinically infected dentin/caries. ALWAYS remove

affected= demineralization, dentin softened, partially lost minerals. Stopped caries can result in remineralization which can be left behind

sound=healthy dentin

Infected dentin is ______ in texture

soft and wet, leathery. SOME can be left behind when it is near the pulp, but margins are ALWAYS cleaned out

What type bur is used to clear out dentin

latch type bur (round carbide) WITHOUT water (6-8,000 rpm)

What type flakes does normal dentin have

dry flakes

Breakdown of dentin/enamel to the pulp chamber is....

sometimes not restorable

Order of dentin lesion progression

sclerosis (dark areas), demineralization, tertiary dentin, nerve infection

Once the lesion has passed the _____ progression of the lesion is much quicker

dentoenamel junction

Root surface lesion

plaque stagnation can occur under caries

Calculus

opposite of caries, it is tarter so plaque is remineralizing to become calcified where caries demineralized to become calcified

There are _____ minerals closer to the pulp

LESS> tubules are wider and closer to the pump

You can _____ a lesion when it is not cavitated, you do not always have to _____

arrest; drill

Sugars

arch nemesis of teeth

mono, di and polysaccharideds

monosaccharides

glucose, fructose, galactose

Di-saccharides

glucose+fructose (sucrose), galactose+glucose (lactose), glucose+glucose (maltose)

Polysaccharides

body cannot use these, must be broken down by the amylase enzyme. Once broken, it can be metabolized

starch, amylose, amylopectin

Do you want cariogenic challenge to happen often during the day?

NO

Eating a lot of _______ and _____ can lead to a high cariogenic challenge

snacks/sugars; bad dental habits

xylitol

a sugar alcohol that can be ingested by the bacteria but CANNOT be metabolized or produce acidic properties

Artificial sweetners

NOT cariogenic, but not good for ingestion.

Cariogenic bacteria can _______ glucose

metabolize

commonly metabolized into an acid

cariogenic bacteria can NOT metabolize

calcium, polysaccharides, proteins or water

is bonding hydrophobic or hydrophillic

hydrophobic