EXPOSURE AND TECHNIQUE ERRORS DA 105

Dental Radiography Questions What film exposure and technique errors may be observed on dental radiographs? What horizontal and vertical angulation errors may be observed on dental radiographs? What is the proper film placement for bite-wing radiographs?

Dental Radiography Exposure and Technique Errors Film exposure errors Technique errors (periapical films) Technique errors (bite-wing films) Miscellaneous technique errors

Exposure and Technique Errors Purpose To describe film exposure problems and periapical, bite-wing, and miscellaneous technique errors

Film Exposure Errors Exposure Problems Unexposed film Film exposed to light Time and Exposure Factor Problems Overexposed film Underexposed film

Unexposed Film Appearance The film appears clear Cause Failure to turn on the x-ray machine Electrical failure Malfunction of the x-ray machine Correction Make certain the x-ray machine is turned on and listen for the audible exposure signal

An unexposed film appears clear

Film Exposed to Light Appearance Cause Correction 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 light leaks Turn off all lights in the darkroom except the safelight

A film exposed to light appears black

Overexposed Film Appearance Cause Correction Film appears dark Excessive exposure time, kilovoltage, milliamperage Correction Check settings and reduce as needed before exposing film

An overexposed film appears dark

Underexposed Film Appearance Cause Correction The film appears light The film was underexposed Correction Check the exposure time, kilovoltage, and milliamperage settings on the x-ray machine before exposing the film

An underexposed film appears light

Technique Errors (Periapical Films) Film Placement Problems Correct film placement Incorrect film placement Absence of apical structures Dropped film corner Angulation Problems Incorrect horizontal angulation Incorrect vertical angulation 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 incisal or occlusal surfaces of the teeth and extend 1/8th inch beyond the incisal or occlusal surfaces

Correct periapical film placement demonstrates the entire tooth, including the apex and surrounding structures

Absence of Apical Structures Haring (p. 276) (Fig. 20-6) 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 inch of the film edge extends beyond the incisal-occlusal surfaces of the teeth

Improper film placement; no apices appear on this film

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

  Improper film placement; a dropped film corner is seen when the edge of the film is not placed parallel to the incisal or occlusal surfaces of the teeth

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

Incorrect horizontal angulation results in overlapped contact areas

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

If the vertical angulation is too steep, the image of the tooth on the film is shorter than the actual tooth; the images are foreshortened

Incorrect Vertical Angulation Elongated images Appearance Long, distorted teeth Cause The vertical angulation was insufficient Correction Use adequate vertical angulation with the bisecting technique

If the vertical angulation is too flat, the image of the tooth on the film is longer than the actual tooth; the images are elongated

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 centered over the film

A cone-cut is seen when the PID is not properly aligned with the periapical film-holding device

PID Alignment Problems Cone-cut without film holder Appearance A clear area appears on the film Cause The PID was not directed at the center of the film Correction Make certain the x-ray beam is centered over the film

A cone-cut appears as a curved unexposed (clear) area on a radiograph

Technique Errors (Bite-Wing Films) Film Placement Problems Correct film placement 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 Premolar bite-wing The resulting film shows both the maxillary and mandibular premolars and distal contact areas of both canines Molar bite-wing The resulting film shows both the maxillary and mandibular molars

Correct film placement for the premolar bite-wing

Correct film placement for the molar bite-wing

Incorrect Film Placement Premolar bite-wing 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

Incorrect film placement for the premolar bite-wing

Incorrect Film Placement Molar bite-wing 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

Incorrect film placement for the molar bite-wing

Incorrect Horizontal Angulation 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

Overlapped interproximal contacts result from incorrect horizontal angulation

Incorrect Vertical Angulation 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

Incorrect vertical angulation causes the images to appear distorted

Cone-Cut With Film Holder 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

A, A cone-cut is seen when the PID is not properly aligned with the bite-wing film-holding device. B, A cone-cut can also be produced with rectangular collimation; the PID is not properly aligned with the bite-wing film-holding device

Cone-Cut Without Film Holder Appearance A clear area appears on the film Cause The PID was not directed at the center of the film Correction Make certain the x-ray beam is centered over the film

A cone-cut appears as a curved unexposed (clear) area on a radiograph

Miscellaneous Technique Errors Film Bending Film Creasing Phalangioma Double Exposure Movement Reversed Film

Film Bending Appearance Cause Correction Images appear stretched and distorted Cause The film was bent excessively Correction Check film placement before exposure

A bent film appears distorted

Film Creasing Appearance Cause Correction A thin radiolucent line appears on the film Cause The film was creased Correction Do not bend or crease the film excessively

A film crease appears as a thin radiolucent line

Phalangioma Appearance Cause Correction Haring (p. 282) (Fig. 20-23) The patient’s finger appears on the film Cause The patient’s finger was positioned in front of the film Correction Make certain the patient’s finger is placed behind the film

This film demonstrates a phalangioma; the bones of a patients finger appear on the film

Double Exposure Appearance Cause Correction A double image appears on the film Cause The film was exposed twice in the patient’s mouth Correction Always separate exposed and unexposed films

This film demonstrates a double exposure

Movement Cause Correction Appearance Blurred images appear on the film The patient moved during exposure of the film Correction Instruct the patient to remain still while the film is being exposed

Movement results in a blurred image

Reversed Film Appearance Light images with a herringbone pattern appear on the film Cause The film was placed backward in the mouth and then exposed Correction Always place the white side of the film adjacent to the teeth

A reversed film appears light with a herringbone (or tire-track) pattern. The tire-track pattern is seen on the lead-foil backing within the film packet

EXPOSURE AND TECHNIQUE ERRORS DIAGNOSTIC DENTAL RADIOGRAPH: 1.FILM EXPOSURE ERRORS: EXPOSURE PROBLEMS a) Unexposed film APPEARANCE CAUSE CORRECTION b) Film exposed to light TIME AND EXPOSURE FACTOR PROBLEMS a) Overexposed film b) Underexposed film

TECHNIQUE ERRORS(PERIAPICAL FILMS) FILM PLACEMENT PROBLEMS ANGULATION PROBLEMS PID ALIGNMENT PROBLEMS

FILM PLACEMENT PROBLEMS ERROR APPEARANCE CAUSE CORRECTION CORRECT FILM PLACEMENT INCORRECT FILM PLACEMENT a) ABSENCE OF APICAL STRUCTURES b) DROPPED FILM CORNER

ANGULATION PROBLEMS APPEARANCE CAUSE CORRECTION ERROR INCORRECT HORIZONTAL ANGULATION INCORRECT VERTICAL ANGULATION a) FORESHORTENED IMAGE b) ELONGATED IMAGE

PID ALIGNMENT PROBLEMS ERROR APPEARANCE CAUSE CORRECTION CONE-CUT WITH FILM HOLDER CONE-CUT WITHOUT FILM HOLDER

TECHNIQUE ERRORS(BITE-WING FILMS) FILM PLACEMENT PROBLEMS ANGULATION PROBLEMS PID ALIGNMENT PROBLEMS

FILM PLACEMENT PROBLEMS ERROR CORRECT FILM PLACEMENT 1)PREMOLAR BITE-WING 2)MOLAR BITE-WING INCORRECT FILM PLACEMENT

INCORRECT HORIZONTAL ANGULATION INCORRECT VERTICAL ANGULATION ANGULATION PROBLEMS ERROR APPEARANCE CAUSE CORRECTION INCORRECT HORIZONTAL ANGULATION INCORRECT VERTICAL ANGULATION

PID ALIGNMENT PROBLEMS ERROR APPEARANCE CAUSE CORRECTION CONE-CUT WITH FILM HOLDER CONE-CUT WITHOUT FILM HOLDER

MISCELLANEOUS TECHNIQUE ERRORS APPEARANCE CAUSE CORRECTION 1.FILM BENDING 2.FILM CREASING 3.PHALANGIOMA 4.DOUBLE EXPOSURE 5.MOVEMENT 6.REVERSED FILM