Types of Dental Films
Periapical
Intraoral Dental Films Continued
- shows entire tooth from the incisal or occlusal edge to 2-3mm beyond the apex
- used to diagnose pathologic conditions of the tooth, root and bone, tooth formation and eruption
- used especially in endodontics and oral surgical procedures
- silver halide crystals absorb radiation during x-ray exposure and store energy emitted from the radiation which is known as latent image
Bitewing
FUN FACTS?
Intraoral Dental Films
- switching from E to F speed film is 20-25% decrease in exposure to patients
- switching from D to F speed film is 60% decrease in exposure to patients
- shows crowns of both arches and part of the roots
-decay interproximally,
-recurring decay under restorations
-periodontal disease
- check the fit of crowns or metallic fillings
- consist of semi flexible acetate film base that's coated on both sides with emulsion of silver bromide, silver halide, and silver iodide
- thickness of emulsion and presence of special radiosensitive dyes determine film speed
Occlusal
- shows large areas of the maxillary or mandibular arches
- used to locate retained roots of extracted teeth and supernumerary unerupted or impacted tooth
- locate salivary stones and fractures of maxilla or mandible
- examines cleft palates and measures changes in size or shape of maxilla and mindible
Extraoral Dental Films
Otto Walkhoff discovered the first intraoral dental radiograph in 1895
- designed for use in cassettes
- examine large areas of the head and jaws.
- screen film and non screen film
- shows bony and soft tissues of facial profile
What are intensifying screens?
References
- intensifies the effect of radiation which decreases exposure time
- coated with phosphor that gives off light when struck by x-radiation
- speed of the screen depends on the type of phosphor and the size of the crystals.
Chen, C., Lin, S., Chiu, H., Lin, Y., Chen, Y., & Lin, L. (2007). An aiming device for an extraoral radiographic technique. Journal Of Endodontics, 33(6), 758-760.
Screen film
Sommers, T., Mauriello, S., Ludlow, J., Platin, E., & Tyndall, D. (2002). Pre-clinical performance comparing intraoral film and CCD-based systems. Journal Of Dental Hygiene, 76(1), 26-33.
- shows the wide view of upper and lower jaws on a single radiograph
- used to locate impacted teeth, detect lesions in the jaw and observe eruption patterns
- more sensitive to light emitted by the phosphor in intensifying screen than it is to radiation
- Green-sensitive is used with cassettes with rare earth intensifying screens
- Blue-sensitive film is used with cassettes with calcium tungstate intensifying screens
Nonscreen film
- does not require intensifying screens
- the emulsion is sensitive to direct x-ray
- requires more exposure time