Intro to Radiology

Who discovered X-rays? When?

William Roentgen; November 8, 1895

How did Roentgen accidentally discover x-rays?

when he evacuated a cathode ray tube of air, filled it with special gas, and passed a high voltage through it, it produced invisible rays capable of passing through heavy paper and causing a fluorescent glow, which he named X-rays

First human radiograph

of Roentgen's wife!

What did JJ Thompson discover?

it was discovered that cathode rays were made of tiny negatively charged "corpuscles" (later called electrons), particles less than 1/1000th the mass of a hydrogen atom, earning the Nobel Prize for revealing that they were not waves or ions but a new fundamental particle

Otto Walkoff

Made the first dental radiograph - 25 minute exposure

C. Edmund Kells

first practical use of dental radiographs in the U.S. on a living person, but years of daily x-ray exposure cost him his fingers, then his hands, and eventually his arms

William Coolidge

Invented the first x-ray tube in 1913 - "Coolidge tube" with tungsten filament to create heat

Why do we take radiographs?

to detect and confirm oral diseases or conditions, locate lesions or foreign objects, guide procedures, evaluate growth, monitor changes, document patient status, and aid in treatment planning

Dental radiology

use of radiant energy (ionizing and non-ionizing) in the diagnosis and treatment of diseases of the head and neck

What was dental radiology originally called?

roentgenology

X-Ray

BEAM of energy that has the power to penetrate substances and record image shadows on receptors (photographic film or digital sensors)

Radiograph

IMAGE/PICTURE produced on a receptor (Radiation-sensitive film, phosphor plate, or digital sensor) by exposure to ionizing radiation

X-ray Arm

Attaches the tube head and allows for positioning.

X-ray Wall Mount bracket

supporting and positioning X-ray equipment and accessories

Beaming indicating device (BID) or Position indicating device (PID)

guides the direction of the x-ray beam

X-Ray Tube head

generating X-rays - through housing the x-ray tube

X-ray Yoke

the handle

Intraoral images

means inside mouth

What are the 3 types of intraoral images?

periapical, bitewing, occlusal

Periapical

"around the root" to see entire tooth and surrounding bone

Bitewing

upper and lower crowns together and bone levels

Occlusal

larger area of the arch

What is method is used for looking for interproximal decay?

bitewing

Which method is used a lot in Peds dentistry? And why?

occlusal, helps see development of teeth

FMX

full mouth series of radiographs

Beam alignment device/XCP kit

helps to angle where to place the beam

Extraoral

outside of the mouth

Panoramic x-ray

to identify various issues including impacted teeth, jaw and sinus problems, cysts, tumors, and gum disease

Cephalometric

mainly used in ortho but it helps to see development

Anterior teeth

maxillary and mandibular centrals, laterals, and canines

Posterior teeth

maxillary and mandibular premolars and molars

Radiopaque

"bright" or "white" structures - something you cannot see through and thick structure block x-rays from going through

Radiolucent

"dark"

Is a enamel going to be radiolucent or radiopaque?

radiopaque

Is a DEJ going to be radiolucent or radiopaque?

radiopaque

Is a dentin going to be radiolucent or radiopaque?

radiopaque

Is a pulp chamber going to be radiolucent or radiopaque?

radiolucent

Is a furcation going to be radiolucent or radiopaque?

radiopaque

Is a root canal going to be radiolucent or radiopaque?

radiolucent

Is a cementum going to be radiolucent or radiopaque?

radiopaque

Is a soft tissue going to be radiolucent or radiopaque?

radiolucent

Is a CEJ going to be radiolucent or radiopaque?

radiopaque

What makes a good radiograph

clear image, good detail, correct posture, correct teeth and structures in image

How many total images do we take for a full mouth radiographic series?

14-20

What do we need to make sure we get with Periapicals?

entire length of the tooth and surrounding bone

Why do we take PAs?

show roots and surrounding bone

What do we need to make sure we get with Bitewings?

crowns of both maxillary and mandibular teeth on same radiograph

Why do we take bitewings?

show caries, margins of restoratios, and alveolar crest better

Why do we take a Occlusal?

evaluating extent of disease in jaw, showing development of jaw

Intraoral equipment

x-ray unit, computer, digital sensor, and beam alignment device

Central ray

beam as it exits directly from the PID

Long axis of the tooth

imaginary line of the tooth that divides in two equal parts

receptor

digital sensor or film

What are the two principle techniques of intraoral imaging?

paralleling and bisecting

Paralleling

preferred method, less distortion

Bisecting the angle

used when parallel position is not possible (anatomical limitations)

How do we place the receptor when we use the bisecting angle?

as close to the tooth as possible

How should the central xray beam be when using bisecting angle?

directed perpendicular to an imaginary line that bisects or divides the angle formed by the long axis of the tooth and the plane of the image receptor