exam 3

what is the original method of taking pas

bisecting tech

now we use parallel

2 PA techniques

1. paralleling technique-preferred, film placed parallel to long axis of tooth
2. bisecting the angle-used when anatomical configurations don't allow prior-angle cone so that in between film resting on tooth and palate and long axis of the tooth

when do you use the bisecting tech

if you can't use parallel bc pat has
shallow palate
tori
sensitive floor of mouth
unable to close on bite block

rule of isometry

two triangles are equal if they have two equal angles and share a common side

what angle does rule of isometry use

90 degrees

how does receptor lay in bi tech

lays more flat against tooth and is closer

what is different in bi and para tech

VA:
-bisect: beam directed at bisecting line
-para: VA perpen to long axis of tooth/receptor

receptor placements
bisect: more flat/close to tooth
para: closer to midline

what is same in bisect and para tech

!!!horizontal angulation: central ray through contacts

pat prep same
equipment prep same
exposure sequence same

!!!receptor exposure same: beam centered on receptor

Receptor position (bisecting)

against lingual surface on tongue

extended 1/8 in beyond incisal/occlusal

Rules for Bisecting Technique

1. Receptor placement: over prescribed teeth

2. Receptor position: against lingual surface of tooth and extened 1/8inch beyond occlusal/incisal

3. Vertical angulation: central ray perpen to imaginary bisecting line

4. Horizontal angulation: central ray through contacts

5. Receptor exposure: beam centered on receptor

va for bisecting tech

central ray is perpen to imaginary bisector

patient positioning bisecting

occlusal plane parallel to floor

midsag perpen to floor

name 3 holders for receptor stabilization

rinn bai

snaparay

staibs

rinn bai

for bi tech

has bite blocks with angled part

Snaparay

receptor clips in

used for bi tech

staibs

disposable

use post/ant bite block

advantages of bisecting technique

alternative if you cant use BAD

shorter PID can be used so shorter exposure time

disadvantages of bisecting tech

cant use bad

increased risk of image distortion

angulation problems bc of no bad

can you use bad for bisecting tech

no
only para

what is the goal or bisecting tech

produce image same length as tooth

what are 2 common errors for bi tech

foreshortening (pid too steep)

elongation(pid too flat)

imaginary bisector

c

plane of the receptor

d

central ray

a

long axis of tooth

b

Correct Bisecting Angle

in bi tech pid para to what

imaginary bisecting line

not long axis of tooth(para)

elongation

pid too flat

Foreshortening

pid too steep

if a short pid is used

use shorter exposure time

Receptor size for bisecting technique

size 2 ant/post

bad reccommended for bi tech to aid in aligning pid and reduce pat exposure

rinn bai

central ray in bi tech is what to imaginary bisector line

90 degrees

distance btwn receptor and tooth in bi tech

receptor as close as possible to tooth

are there more pros or cons to bi tech

disadvantages outweigh the positives

The exposure sequence for the bisecting technique

mx r canine
max incisors
max l canine
mand canine l
mand incisor
mand canine r
mx premolar to molar
mand premolar to molar

Goal of infection control

minimize potential for disease transmission

pathogens

microorganisms that are capable of causing infection and disease

direct contact with pathogens

blood in saliva
respiratory secretions
lesions touching it

ex: not using gloves if pat infected

indirect contact with contaminated surfaces

ex: touching a contaminated sensor with no gloves

direct contact with airborne transmission

pat sneeze and You didnt wear a mask

3 modes of transmission

direct, indirect, airborne

3 things needed for disease transmission

susceptible host

pathogen with sufficient infectivity and numbers to cause infection

portal of entry (ex: mucous memb)

asepsis

state/absence of harmful pathogens that cause disease

disinfect

treatment of chem/physical procedures to inhibit/destroy pathogens

sterilize:

destroy all microorganisms and spores

ex of sterilization and disinfection

sterilizeL: autoclave

disinfect: caddy wipes

Disinfection vs. Sterilization

•* Disinfection *\= Destroying PATHOGENIC microbes except for spores (ie chemical disinfection, pasteurization)

•* Sterilization *\= Killing ALL microbes (good & bad) (ie autoclave, flash sterilization, low temp sterilization)

3 exs of ppe

protective clothing
gloves
masks/eyewear

when must gloves be worn

When hand contact with blood, saliva, mucous membranes

when should gloves be changed

BETWEEN PATIENTS AND WHEN TORN/PUNCTURED

when do you changes masks

btwn pats

why do you wear mask/eyeweat

when splatter/aerosolized sprays of blood/saliva likely

3 methods of hand hygiene

soap and water
antispetic wash
hand rub

when to use hand rub vs antiseptic wash

use either anytime

unless hands visibly soiled use hand wash

when to do hand hygiene

before + after treatment
after removing gloves
after contacting contaminated objects
before leaving
is visibly soiled(hand wash)

Critical instruments

Item used to penetrate soft tissue or bone

none in rad, ex scapel

Semicritical instruments

contact mucous membranes but do not penetrate body tissues

rad: bad

Noncritical instruments

do not come in contact with mucous membranes

rad: pid/tubehead, exposure button, keyboard/mouse

what do you disinfect in clinic

anything that cant be sterilized

caddy wipes used to wipe room

prep steps for ic

disinfect area
put barriers
gather needed supplies

after procedure ic

disposed of of disposables
hand hygiene
disinfect

ic for wired sensor

use barrier
wipe with caddy wipe after use

why do we wipe the sensor

barrier sleeve can be punctured

psp ic 6 steps

1. cover with barrier
2. wipe with paper towel to remove excess saliva
3. collect and put into dispoable container when done using
4. move it to the scanning station
5. remove barrer with gloves and without touching the plate
6. remove gloves and put in scanner

how can you touch a sensor

with clean hands

never touch with contaminated gloves

film with barrier ic steps

1. collect and put in cup
2. remove gloves
3. put a paper towel down in dark room
4. don gloves
5. tear open barrier
6. drop film onto paper towel, dont touch it
7. hand hyg
8. open film without gloves
9. process film

film with no barrier ic steps

1. collect and put in cup
2. remove gloves
3. put a paper towel down in dark room
4. turn off light in darkroom
5. open film packet and slide out the foil/blacker paper
6. drop film onto paper towel, dont touch it
7. hand hyg
8. open film without gloves
9. process film

Occupational exposure

exposure to disease in the workplace

Parenteral exposure

Exposure to blood or other infectious materials that results from piercing or puncturing the skin barrier

how often to change ppe

daily/when visibly soiled

do you wash gloves

no

Intermediate level disinfectant

EPA-registered hospital disinfectant with tuberculocidal claim

Low-level disinfectant

EPA-registered chemical germicides that are labeled only as hospital disinfectants and are for general house keeping purposes

what needs to be disinfected in rad

xray
chair
area
lead apron

purpose of occlusal technique

used in additon to bw/pa to examine large areas of max and mand

why are occlusals usually taken

to learn more about something in a pa/bw or to see from a dif angle

what are you looking for in occlusals

know 5

retained root tips
foreign bodies
max sinus boundaries
cleft palate
supernumary/unerupted/impact teeth
extent of lesions

Principles of occlusal technique

-Receptor is placed w/ tube side facing arch being exposed.
-Receptor is placed in mouth btwn occlusal surfaces of maxillary and mandibular teeth.
-Receptor is stabilized when patient bites on surface of receptor.

receptor size for occlusal traditonal film/psp plate

kid + adult

size 4 adult

size 2 children

occlusal receptor digital size

size 2

2 occlusal techs

topographic

cross sectional

how do topographic images appear

like a large pa

how do cross-sectional images appear

shortened and circular

crosssectional mostly used on

mand to cover sublingual calcifications and impacted teeth

Max Pediatric Occlusal Projection use

used to determine where teeth are if perm teeth no erupting

can see how close to eruption/if even there

Max Pediatric Occlusal Projection how to

max parallel to floor

receptor faces cone
kid bites down gently
goes across arch

use 60+ angulation

Max Pediatric Occlusal Projection angulation

60+

btwn eyerbows and bridge of nose

localization technique

Method used to locate the position of a tooth or object in the jaws

see if buccal/lingual

localization technique methods

buccal object rule

right angle tech

why do we use localization techs

2d image of 3d object

cant tell sup/inferior or ant/post realtionships

cant tell if buccal/lingual(why its used)

Buccal object rule

slob

same lingual
opposite buccal

how to use buccal object rule

1. expose pa/bw using proper tech
2. change direction of xray (va or ha)
3. compare images
4. use slob rule

right angle technique

A localization technique in which the orientation of structures can be seen in two radiographs (one periapical and one occlusal)

right angle technique how to

expose one pa receptor with proper tech

expose an occlusal receptor and direct central ray perpen to receptor

can see buccal/lingual

Uses of Occlusal Technique

locate roots, extra/unerupted/impacted teeth, foreign objects, salivary stones, lesions

Max topographic va

+65

max pediatric occlusal va

\+60

max lateral occlusal projection va

+60

Mand topographic projection va

-55