Radiation comes in two forms - particulate and electromagnetic. Dental radiographs use x-rays to produce images of teeth and surrounding structures. There are three main types of intraoral dental x-rays: periapical for the tooth apex, bitewing between teeth, and occlusal for larger areas. Dental films contain a silver halide emulsion layered between a transparent base and protective coating to capture x-ray images.

2. Radiation: is energy that comes from a
source and travels through space and
may be able to penetrate various
materials. It’s may occur in two forms :
1. particulate radiation ,
2.electromagnetic radiation .
Dental radiograph: a photographic image
produced on film by passage of x –ray
through teeth & related structures.

3. Intraoral x-ray :
1.Periapical radiograph : which used to
examine apical area of the tooth and the
surrounding structure .

4. Indications for
Periapical radiograph:
1.Detection of apical cyst 2.Evaluation of implants

5. 2.Bitwing radiograph : it used to examine the
crown of both the maxillary & mandibular
teeth on one film.

6. Indications for
bitwing radiograph:
1. Evaluate inter proximal
carious teeth
2. Evaluate over hanged
filling

7. 3.Occlusal radiograph : that used to
demonstrate an area of greater dimension than
area appear in periapical radiograph,
With the longest
Dimension of the film in
A anterioposterio
Position.

8. Indications for
occlusal radiograph:
1. To evaluate fractures of
maxilla or mandible
2. To locate supernumerary
teeth

9. Dental films:The media on which the
radiographic images of objects are
recorded, there is 2 types of films:
1.Self developing films :
2. Manual or wet processing films:

10. X_ray films :
X-ray film base composition :
Protective gelatin layer
Adhesive
Emulsion
( silver halide)
Film base
Cross sectional structure of double emulsion film

11. 1) Film base; clear transparent sheet of
cellulose acetate with a bluish tint.
2) Adhesive; connects the emulsion to the
base.
3) Emulsion; on both sides of the base
where silver bromide(AgBr) crystals are
distributed in an the gelatin emulsion
4) Protective layer; protects the emulsion
from mechanical damage

12. 1) Outer plastic wrapper; protects the film from
light, saliva and mechanical damage, has two
sides:
2) *Front; faces the x-ray tube, single color
(white)
3) *Back; opposite side to x-ray tube, two colors
(white and green). It has an opening tab to
open the film during processibg
4) Black paper wrapper; protects the film base
from light, saliva and damage during opening

13. 1) Lead foil; thin sheet of lead present at the back of
the film, has certain shapes on its surface, it:
2) *prevents x –rays from going to deeper tissues
after passing through the film
3) *prevents scattered radiation from deeper tissues
to come back to the film
4) Raised dot; an elevation embossed on each
component of the film,has two surfaces
5) Convex; indicates front of the film (facing x-ray)
6) Concave; indicates back of film (facing lead foil)

14. Outer plastic cover
Front Back
Film
Lead
foil
Protective black paper