exposure and technique errors Flashcards
appearance, cause and correction for unexposed film
- appearance: the film appears clear
- cause: failure to turn on the x-ray machine, electrical failure or malfunction of the x-ray machine
- correction: make certain the x-ray machine is turned on and listen for the audible exposure signal
appearance, cause and correction for film exposed to light
- appearance: the film appears black
- cause: the film was exposed to white light
- correction: do not unwrap in a room with white light, check the darkroom for leaks, and turn off all lights in the darkroom except safelight
appearance, cause and correction for overexposed film
- appearance: film appears dark
- cause: excessive exposure time, kilovoltage, milliamperage
- correction: check settings and reduce as needed before exposing film
appearance, cause and correction for underexposed film
- appearance: the film appears light
- cause: the film was underexposed (results from inadequate exposure time, kilovoltage or milliamperage)
- correction: check the exposure time, kilovoltage, and milliamperage settings on the x-ray machine before exposing the film
technique errors for periapical films
- film placement problems
- angulation problems
- PID alignment problems
technique errors for periapical films: film placement problems
- correct film placement
- incorrect film placement: absence of optical structures, dropped film corner
technique errors for periapical films: angulation problems
- incorrect horizontal angulation
- incorrect vertical angulation
technique errors for periapical films: PID alignment problems
- cone-cut with film holder
- cone-cut without film holder
correct film placement
- each periapical film must be positioned in a certain way to show specific teeth and related anatomic structures
- the edge of the periapical film must be placed parallel to the incisor or occlusal surfaces of the teeth and extend 1/8th of an inch beyond the incisal or occlusal surfaces
appearance, cause and corrections for absence of apical structures
- appearance: no apices appear on the film
- cause: the film was not positioned in the patient’s mouth to cover the apical regions of the teeth
- correction: make certain no more than 1/8th of an inch of the film edge extends beyond the incisal-occlusal surfaces of the film
appearance, cause and corrections of dropped film corner
- appearance: the occlusal plane appears tipped or tilted
- cause: the edge of the film was not placed parallel to the incisal-occlusal surfaces of the teeth
- correction: make certain the edge of the film is placed parallel to the incisal-occlusal surfaces of the teeth
appearance, cause and correction for incorrect horizontal angulation
- appearance: overlapped contacts
- cause: the central ray was not directed through interproximal spaces
- correction: direct the x-ray beam through interproximal regions
appearance, cause and correction for incorrect vertical angulation: foreshortened images
- appearance: short teeth with blunted roots
- cause: excessive vertical angulation
- correction: do not use excessive vertical angulation with the bisecting technique
appearance, cause and correction for incorrect vertical angulation: elongated images
- appearance: long, distorted teeth
- cause: the vertical angulation was insufficient
- correction: use adequate vertical angulation with the bisecting technique
appearance, cause and correction for PID alignment problems: cone cut with film holder
- appearance: a clear area appears on the film
- cause: the PID was not properly aligned with the periapical film holder
- correction: make certain the x-ray beam is entered over the film
appearance, cause and correction for PID alignment problems: cone cut without film holder
- appearance: a clear area appears on the film
- cause: the PID was not directed at the centre of the film
- correction: make certain the x-ray is entered over the film
technique errors for bite-wing films:
- film placement problems: correct and incorrect film placement
- angulation problems: incorrect horizontal angulation, incorrect vertical angulation
- PID alignment problems: cone-cut with film holder, cone cut without film holder
correct film placement for premolar bite-wings
- the resulting film shows both the maxillary and mandibular premolars and distal contact areas of both canines
correct film placement for molar bite-wings
- the resulting film shows both the maxillary and mandibular molars
appearance, cause and correction for incorrect film placement for premolar bite-wings
- appearance: distal surfaces of the canines are not visible on the film
- cause: the bite-wing film was positioned too far posteriorly in the mouth
- correction: make certain the anterior edge of the bite-wing film is positioned at the midline of the mandibular canine
appearance, cause and correction for incorrect film placement for molar bite-wings
- appearance: third molar regions are not visible on film
- cause: the bite-wing film was positioned too far anteriorly in the mouth
- correction: make certain the anterior edge of the bite-wing film is positioned at the midline of the mandibular second premolar
appearance, cause and correction for incorrect horizontal angulation in bite-wings
- appearance: overlapped contacts on the film
- cause: the central ray was not directed through the interproximal spaces
- correction: direct the x-ray beam through the interproximal spaces
appearance, cause and correction for incorrect vertical angulation is bite-wings
- appearance: images appear distorted on the film
- cause: the vertical angulation was incorrect
- correction: always use a +10 degree vertical angulation with the bite wing technique
appearance, cause and correction for cone-cut with film holder in bite-wings
- appearance: a clear area appears on the film
- cause: the PID was not properly aligned with the film holder
- correction: make certain the PID and the aiming ring are aligned
