DETH 102 MIDTERM REVIEW

Functions of primary teeth

- Maintenance of a proper diet

- Space maintenance

- Efficient mastication of food

- Maintenance of normal facial appearance

- Formation of clear speech

How many teeth are in there permanent dentition?

32 teeth

How many teeth are in the primary dentition?

20 teeth

Anatomical features of teeth

• Anatomical features of the teeth help maintain their positions in the arch and protect the tissues during mastication

Three anatomical features:

• Contours

• Contacts

• Embrasures

Furcation

• The point at which the roots of a multirooted tooth divide

• Bifurcation for two rooted teeth

• Trifurcation for three rooted teeth

Bicanineate and Tricanineate

• A bicanineate 2 cusp premolar

with have a groove that is

shaped like a "H" or "U"

• A tricanineate premolar is most

common.

• The groove in a 3 cusp premolar

is a "Y" shape

Lobe

A lobe is a growth center in the development of

the crown of a tooth, and it is represented by a

cusp on posterior teeth and mamelons and

cingula on anterior teeth.

The number of lobes in a tooth depends on the

type and function of the tooth.

As a general rule, the facial portion of anterior

teeth (incisors and canines) forms from three

lobes, and the lingual cingulum area forms from

one lobe.

Premolars and molars form from one lobe per

cusp, which can vary from two to five.

Therefore, most normal teeth show evidence of

having developed from three to five lobes.

Cusps

• A cusp is a pyramidal elevation with a peak called a cusp tip.

• Cusps are located on the occlusal surfaces of molars and premolars

and on the incisal surfaces of canines.

• Canines have one cusp, premolars normally have two or three cusps,

and most molars have from three to five cusps.

• On teeth with multiple cusps, each cusp is named according to its

location on the tooth.

Anterior Tooth Ridges

• Mesial marginal ridge

• Distal marginal ridge

• Incisal ridge

• Cusp ridge (cusp slope)

• Mesial cusp ridge

• Distal cusp ridge

• Labial ridge

Posterior Tooth Ridges

• Mesial marginal ridge

• Distal marginal ridge

• Triangular ridge

• Transverse ridge

• Oblique ridges

• Cervical ridge

• Buccal Ridge

• Lingual Ridge

Marginal Ridges

• Rounded, raised borders on the

mesial and distal surfaces

• Mesial marginal ridge

• Distal marginal ridge

• Located on the lingual surfaces of

anterior teeth and occlusal surfaces

of posterior

Transverse Ridge

• Crosses the occlusal surface

from buccal cusp to lingual cusp

• Made up of two triangular ridges

almost directly across from each

other

Oblique ridge

• Located on the occlusal maxillary molars

• Runs in an oblique (diagonally) directionfrom mesiolingual cusp to distobuccalcus

Triangular Ridges

• Ridges that descend from the cusp tips toward the central portion of the occlusal table.

Cusp or cusp slope (ridge)

found on all cusps running in a M or D direction

Marginal (ridge)

form the M and D shoulders on the occlusal surfaces of posterior teeth and on the lingual surfaces of anterior teeth

Triangular (ridge)

runs from the tip of each cusp towards the center of the occlusal surface

Transverse (ridge)

the union of 2 triangular ridges directly across from each other in a B -Li direction

Oblique (ridge)

found on maxillary molars from the MLi cusp to the DB cusp

Cervical (ridge)

runs in a M-D direction found on the B surface of permanent molars and all deciduous teeth

Buccal (ridge)

found on the B surface of premolars from the cusp tip towards the cervical line.

Labial (ridge)

found on the La surface of canines from the cusp tip towards the cervical line

Lingual

found on the Li surface of canines running from the cusp tip towards the cervical line

Cingulum

• All anterior teeth have a cingulum ,a rounded, raised area on the cervical third of the lingual surface

• The cingulum corresponds to thelingual developmental lobe

Fossa

shallow depression

Some anterior teeth have a fossa, which is a wide, shallow depression on the lingual surfaces

Sterilizer monitoring

• We use different types of monitoring because we cannot determine

that each individual instrument is sterile just by running through

machine.

• Integral part of the overall sterilization process to achieve a sterility

assurance level (99.9999% probability of success)

• Monitoring is done to ensure proper operation & if sterilization has

actually occurred.

3 Forms of Sterilization Monitoring

• Mechanical Monitoring

• Chemical Monitoring

• Biological Monitoring

Chemical Monitoring Classes Class 1

Class 1 (process indicators)

• Distinguish processed from unprocessed items

• Indicator tape, labels, integrated packaging• Use on every package

Chemical Monitoring Classes Class 2

Class 2 (specific test indicators)

• Evaluate sterilizer performance

• Measure specific attributes such as air

removal or steam penetration

• DART (Daily Air Removal Test)

• results are immediately visible through the

clear vial. A uniform color change from

yellow to black indicates that all the air was

removed and replaced by steam.

• Used at beginning of day in empty load near

the drain opening of sterilizer.

• Bowie-dick tests

• Prior to first load

Chemical Monitoring Classes Class 3

Class 3 single variable indicators

• Respond to single variable (time or temp)

• A chemical pellet which melts at a specific temperature

• Pack control monitoring - not typically used in health care

Chemical Monitoring Classes Class 4

Class 4 multi-variable indicators

• Respond to two or more of the critical variables (time, temp, presence of steam)

• Used for internal pack control for every package

Chemical Monitoring Classes Class 5

Class 5 integrating indicators

• Used for both load and internal pack control monitoring

• React to all critical process variables (time, temp, presence of steam)

• Used in each load

Chemical Monitoring Classes Class 6

• Class 6 emulating indicators - monitor specific sterilization cycles

Processes

• Cleaning

• Disinfecting

• Sterilizing

Steps

• Removes or reduces bioburden (MO, blood & saliva, tissue fluids, and dental

materials)

• Gives subsequent steps best chance to work.

• Cleaning should precede all disinfection and sterilization processes.

• Cleaning involves the removal of debris (organic or inorganic) from an

instrument or device.

• If visible debris is not removed, it will interfere with microbial

inactivation and can compromise the disinfection or sterilization

process.

Considerations in selecting cleaning methods and equipment include their

effectiveness, their compatibility with the items to be cleaned, and the

occupational health and exposure risks they pose.

Because instruments cleaned with automated cleaning equipment do not

need to be presoaked or scrubbed, the use of automated equipment can:

1. increase productivity

2. improve cleaning effectiveness

3. decrease worker exposure to blood and body fluids

Thus, using automated equipment can be more efficient and safer than

manually cleaning contaminated instruments.

Clean

• Physical removal of debris

• Removes or reduces bioburden

• Gives best chance for

subsequent processes to work

Disinfect

Removal or destruction of pathogens with the use of

chemicals

• Less lethal than sterilization

• Different levels of disinfection

• May not kill endospores

Sterilize

• Destroys all Mo's

• Accomplished by steam and dry heat sterilizers

• Highest level of microbial kill possible

contamination

the process of becoming unclean

Patient care items

Instruments and supplies used to provide dental examinations.

Causes of sterilization failure

Instrument Preparation

• Remaining bioburden

• Instruments not rinsed

or dried

Packaging/Loading

• Wrong material used

• Instruments too

heavy/sharp

• For sterilizer used

• Not sealed

• Overloading sterilizer

• Excessive packaging

Sterilizer Operation

• Mechanically unsound

• Timer malfunction

• Not operating

according to

manufacturer

• Using incorrect cycle

for packaging/items

• Time, temp, pressure

• Opening prior to cycle

completion

• No dry cycle

• Handling instruments

with wet packaging

Sterilizer Monitoring

• Not checking external

and internal indicators

or biological monitor.

• Not observing

sterilizers for correct

operation

Storage

• Taking items out of

packaging for storage

• Using old instruments

due to not rotating

packs

• Torn packages from

frequent handling

• Stored in open storage

units

• Exposure to aerosols

• Near water sources

or heat

direct transmission

direct contact with blood, oral fluids, or other substances.

Modes of transmission

Direct

Indirect

Droplet

Airborne

Vehicle

indirect transmission

Contact with an intermediate contaminated object (i.e, instruments, equipment, or surfaces.)

droplet transmission

Contact of conjunctival (eye), nasal or oral droplets containing micro organisms from an infected person and from a short distance (coughing, sneezing, talking)

airborne transmission

Inhalation of airborne microorganisms suspended in air

Vehicle

contact with a vehicle such as food or water causing the transfer of a pathogen

Bloodborne Pathogens

Disease-causing microorganisms carried in the body by blood or body fluids, such as hepatitis and HIV.

respiratory illness

consists of infection, disease or inflammation of the airways that carry air to and from the exchange surfaces of your lungs.

significance exposures

• Must be dealt with immediately

• Exist when any of the following events occurs:

• Percutaneous injury, where the skin is punctured by a contaminated needle or

sharp instrument (blood is released).

• Blood, saliva or other body fluid is splashed onto non-intact skin (dermatitis, cuts

or abrasions).

• Blood, saliva or other body fluid is splashed onto mucosa of the eyes, the mouth

or the nose.

Exposure to a patient's blood or saliva on intact skin is not considered significant.