intraoral radiographic technique manual radiographic technique manual utilizing the paralleling...

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INTRAORAL RADIOGRAPHIC TECHNIQUE MANUAL

Utilizing the Paralleling Principal

Department of Oral Health & Diagnostic Sciences

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A full mouth radiographic series (FMX) consists of 20 images composed of periapical (16) and

bitewing (4) projections.

Periapical radiographs are intended to evaluate the periapical region of the tooth and surrounding

bone. Therefore, it is essential to obtain the full length of the tooth and at least 2 mm of

periapical bone.

Bitewing radiographs record, on a single image, the crowns and coronal 1/3 of the interproximal

bone of both arches. Bitewings are useful for detecting interproximal carious lesions, bone

height, pulp chamber size and shape, pulp stones, and overhangs on interproximal restorations.

It is therefore essential to position the image receptor and x-ray beam so that there is an equal

distribution of both arches in the resulting radiographic image.

Instrument Assembly:

The Rinn XCP Instrument for a full mouth series (FMX) of x-rays consists of 3 parts:

1. 3 biteblocks for the anterior, posterior, and bitewing set-ups.

2. 3 Indicator rods for the anterior, posterior, and bitewing set-ups.

3. 2 Aiming rings for the anterior, posterior, and bitewing set-ups.

a. The same aiming ring is used for the anterior and bitewing set-ups

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Posterior RINN set up for upper right and lower left and upper left and lower right, respectively

Posterior RINN set up for Upper right and left respectively

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Posterior RINN set up for Lower right and left respectively

GENERAL RULE FOR PSP PLACEMENT IN RINN INSTRUMENTS: When you look

through the aiming ring, you should ONLY see the sensitive side of the image receptor. The

sensitive side is indicated by the black side of the PSP packet (see below images).

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Videos are available that demonstrate proper operatory set-up, Rinn instrument assembly, and

scanning of PSP plates.

MAXILLARY CENTRAL-LATERAL PROJECTION

Use a #1 size Photostimulable Phosphor (PSP) plate

Center the PSP plate vertically in the anterior bite block with the black dot in the groove

(black dot in the slot) and the black side of the PSP packet towards the source of

radiation.

CORRECT POSITIONING OF THE PSP

Center the CENTRAL-LATERAL INCISOR CONTACT on the PSP plate.

Place the PSP plate as far back into the mouth as possible so that the PSP plate is as

parallel as possible to the long axes of the teeth.

• This is accomplished by engaging the incisal edges of the incisors in the FIRST

OR SECOND GROOVE of the biteblock.

The first or second grooves are located on the outer edge of the biteblock

(edge towards the source of radiation).

Position the PSP-plate so that the appropriate contact will be open (central-lateral

contact).

• This is accomplished by projecting the x-ray beam through the contact area/s of

interest

Press the holder against the MAXILLARY INCISORS FIRST, then have the patient

gently bite together.

NOTE: Sometimes, greater stability of the bite block may be achieved if a cotton roll is

placed BETWEEN the biteblock and the MANDIBULAR TEETH before having the

patient close.

Slide the aiming ring down the indicator rod to approximate the skin surface before

making the exposure.

Resulting radiograph

1. The central-lateral contact should be centered in the image.

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2. At least 2 mm of apical bone is visible above the root apex.

3. Central-lateral contact is open.

MAXILLARY CANINE PROJECTION


Center the PSP plate vertically in the anterior biteblock with the black dot in the groove


radiation.


• Center the CANINE in the middle of the PSP plate.

• Place the PSP plate well away from the palatal surface of the teeth so that the PSP plate is

as parallel as possible to the long axis of the cuspid.

o This is accomplished by engaging the incisal edge of the cuspid in the FIRST or

SECOND GROOVE of the biteblock.

• Position the PSP-plate so that the appropriate contact will be open.

o This is accomplished by projecting the x-ray beam through the contact area of

interest.

o Note: the contact to open is the lateral-canine contact. Do not attempt to open the

distal canine contact; it will be visualized on different views.

• Press the holder against the canine FIRST, then have the patient gently bite together.

• NOTE: Sometimes greater stability of the biteblock may be achieved if a cotton roll is

placed BETWEEN the biteblock and the MANDIBULAR TEETH before having the

patient close.

• Slide the aiming ring down the indicator rod to approximate the skin surface before


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Resulting Radiograph

1. The canine should be centered in the image.


3. The lateral-canine contact is open.

MAXILLARY PREMOLAR PROJECTION • Use a #2 size PSP plate.

• Center the PSP plate HORIZONTALLY in the posterior biteblock with the black dot in the

groove (black dot in the slot) and the black side of the PSP packet towards the source of

radiation.


• Position the PSP plate near the midline of the palate to ensure that the PSP plate is placed

as parallel as possible to the long axes of the premolars

o This is accomplished by engaging the buccal cusps in the First or Second

Groove of the bite block).

• The anterior edge of the PSP plate should be placed adjacent to the maxillary canine on

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the side being radiographed so that the distal ½ of the canine will be included in the

radiographic image.

• Position the PSP-plate so that the appropriate contacts will be open.

o This is accomplished by projecting the x-ray beam through the contact areas of

interest.




1. The distal half of the canine should be visible as well as all of the first and second

premolars and first molar and sometimes also the mesial half of the 2nd molar.


3. The contacts should be open.

MAXILLARY MOLAR REGION

• Use a #2 size PSP plate.



radiation.

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• Orient the PSP plate so that it is as parallel as possible to the long axes of the teeth.

o This is accomplished by placing the buccal cusps of the maxillary teeth in the FIRST

or SECOND GROOVE of the biteblock.

o This will place the upper edge of the PSP plate at or across the midline of the palate.



interest.

• Position the PSP plate to cover the first, second, and third molar areas. The anterior border

should just cover the distal aspect of the second premolar.

o Note: the mesial placement of the edge of the PSP will usually NOT include any of

the 1st premolar.

• Slide the aiming ring down the indicator rod to approximate the skin surface before making

the exposure.


1. Radiograph should show all of the first, second, and third molar areas.



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MANDIBULAR CENTRAL-LATERAL PROJECTION


Center the PSP plate vertically in the anterior biteblock with the black dot in the groove


radiation.


• Center the central-lateral contact in the middle of the PSP plate.

• Engage the biteblock against the INCISAL EDGES of the mandibular incisors in the vicinity

of the center hole.

• The bottom edge of the PSP plate should be placed UNDER THE TONGUE extending

posteriorly into the 2nd premolar-1st molar region.



interest.

• ROTATE the PSP plate DOWNWARD into the floor of the mouth until it is as parallel as

possible to the long axes of the incisors.

• Press lightly downward and backward on the PSP plate and biteblock to ensure that the

holder maintains continuous contact with the incisal edges.

• Note: sometimes greater stability can be accomplished by placing a cotton roll BETWEEN

the top of the biteblock and the MAXILLARY TEETH before having the patient close.


the exposure.


1. The central-lateral contact should be centered in the image.

2. At least 2 mm of apical bone is visible below the root apex.

3. The central-lateral contact is open.

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MANDIBULAR CANINE PROJECTION


Center the PSP vertically in the anterior biteblock with the black dot in the groove (black

dot in the slot) and the black side of the PSP packet towards the source of radiation.


• Center the canine in the middle of the PSP plate.

• The PSP plate is placed under the tongue and across the midline.

• Engage the biteblock against the INCISAL EDGE of the mandibular canine in the

vicinity of the center hole.



interest.

o Note: the contact to open is the lateral-canine contact. Do not attempt to open the

distal canine contact; it will be visualized on different views.

• ROTATE the PSP plate DOWNWARD into the floor of the mouth until it is as parallel as

possible to the long axis of the canine.

• Press lightly downward and backward on the PSP plate holder to ensure that the biteblock

maintains continuous contact with the incisal edge of the canine.

• Note: sometimes greater stability can be achieved by placing a cotton roll BETWEEN the

top of the biteblock and the MAXILLARY TEETH before having the patient close.



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1. The canine should be centered in the image.

2. At least 2 mm of apical bone is visible below the apex.

3. The lateral-canine contact is open

MANDIBULAR PREMOLAR REGION


• Center the PSP plate HORIZONTALLY in the posterior bite block with the black dot in the


radiation.


• Insert the PSP plate and holder into the mouth and carry it past the central incisors to a point

where the anterior edge of the PSP plate is adjacent to the mandibular canine on the side

being radiographed.

• Adjust the PSP plate DOWNWARD past the lateral border of the tongue so that the bottom

edge of the PSP plate will pass BETWEEN THE TEETH AND THE TONGUE.

o Displace the PSP plate medially (toward the middle of the tongue) to make sure

the bottom edge is not pressing against the muscle attachment for the floor of the

mouth.

• The biteblock should rest on the MANDIBULAR occlusal surfaces near the center hole.

• The PSP plate should also be positioned parallel to the lingual surface of the mandibular

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teeth.

• Position the PSP plate so that the appropriate contacts will be open.


interest.

• Ask the patient to gently close together and stabilize the holder, if necessary, with a cotton

roll between the biteblock and the MAXILLARY TEETH.


the exposure.


1. Radiograph should show the distal half of the cuspid, all of the first and second

premolars, the first molar, and sometimes the mesial half of the 2nd molar.



MANDIBULAR MOLAR REGION




radiation.


• Insert the PSP plate and holder into the mouth and carry it past the central incisors to a point

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where the anterior edge of the PSP plate is adjacent to the mandibular second premolar on the

side being radiographed.

• Adjust the PSP plate DOWNWARD past the lateral border of the tongue so that the bottom

edge will pass BETWEEN THE TEETH AND THE TONGUE.

• The bite block should rest on the MANDIBULAR occlusal surfaces near the center hole.



interest.

• Ask the patient to gently close together and stabilize the biteblock, if necessary, with a cotton

roll between the biteblock and the MAXILLARY TEETH.


the exposure.


1. Radiograph should show the first, second and third molar areas.



PREMOLAR BITEWING PROJECTION (horizontal technique)


• Center the PSP plate in the bitewing biteblock with the black side of the PSP packet towards

the source of radiation.

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• Position the PSP plate so that its mesial edge will include the distal half of the mandibular

canine. • Holding onto the edge of the positioning device, place the biteblock in contact with the

MANDIBULAR TEETH.

• Horizontally, position the PSP plate so that the x-ray beam is directed through the

mandibular contacts.

o There may be some difference in the curvature of the mandibular and maxillary

arches. However, when the x-ray beam is accurately directed through the mandibular

premolar contacts, overlapping is minimal or absent in the maxillary premolar

segment.

o Typically this projection requires a +10° angle of the BID (with the patient’s occlusal

plane parallel to the floor).

• Make sure that the PSP plate is BETWEEN the lingual surfaces of the teeth and the lateral

border of the tongue.


the exposure.

Resulting radiograph

1. Radiograph should show an equal distribution of both arches.

2. The distal half of the maxillary and mandibular canines should be visible as well as the 1st

and 2nd premolars, 1st molars and occasionally the second molars.

3. The contacts should be open

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MOLAR BITEWING PROJECTION (horizontal technique)

• Place the PSP plate between the tongue and the teeth and far enough posteriorly to include

the distal of the last erupted tooth in the arch.

• Typically this projection requires a +10° angle of the BID (with the patient’s occlusal plane

parallel to the floor).

• Horizontally, project the x-ray beam through the contact areas of interest. It is helpful to

align the indicator rod with the maxillary contacts.


1. Radiograph should show an equal distribution of both arches.

2. Radiograph should include the distal of the last erupted tooth in the arch.


4. It is preferable to see the distal surfaces of the maxillary and mandibular second

premolars.

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GRU RADIOGRAPHIC TECHNIQUE

MAXILLARY ANTERIOR EXPOSURE

Anterior Rinn Instrument, Use #1 PSP plate, place black dot in the slot, black side towards ring

Patient’s Mouth Open Center area of interest on biteblock Lean biteblock so that teeth are in 1st or 2nd groove

If needed, place cotton roll under the biteblock touching the incisal edges of mandibular anterior teeth

Patient’s mouth closes

• Slide the aiming ring down the indicator rod to approximate the skin surface

• Place cone flush with ring and make exposure

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MANDIBULAR ANTERIOR EXPOSURE

Anterior Rinn Instrument Use #1 PSP plate, place black dot in the slot, black side towards ring

Patient’s Mouth Open Center area of interest on biteblock

Lean biteblock so that teeth are in middle groove

If needed, place cotton roll on top of the biteblock touching the maxillary teeth



Place cone flush with ring and make exposure

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MAXILLARY POSTERIOR EXPOSURE

Posterior Rinn Instrument, Use #2 PSP plate, Place PSP plate horizontally in biteblock, place black dot in the slot,

place black side towards ring

Patient’s Mouth Open

Center area of interest on bite block

Lean biteblock so that teeth are in 1st or 2nd groove

Make PSP plate parallel to lingual of teeth

If needed, place cotton roll below the biteblock touching the occlusal surfaces of mandibular posterior teeth




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MANDIBULAR POSTERIOR EXPOSURE

Posterior Rinn Instrument, Use #2 PSP plate, Place PSP plate horizontally in biteblock, place black dot in the slot,

place black side towards ring


Center area of interest on biteblock

Lean biteblock so that teeth are in middle groove

Make PSP plate parallel to lingual of teeth

If needed, place cotton roll against occlusal surfaces of maxillary teeth


Slide the aiming ring down the indicator rod to approximate the skin surface


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BITEWING EXPOSURE

Rinn Bitewing Instrument, Use size #2 PSP plate, place PSP plate horizontally in holder, dot does not matter, black side

towards ring


Center area of interest on biteblock

Place biteblock against mandibular teeth

Align aiming arm with mandibular contacts (for premolar bitewing projection)

Align aiming arm with maxillary contacts (for molar bitewing projection)


Slide the aiming ring down the indicator rod (aiming arm) to approximate the skin surface


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QUALITY EVALUATION CRITERIA

GENERAL CHARACTERISTICS OF A QUALITY RADIOGRAPH

IMAGE CONTRAST, DENSITY, SHARPNESS, IDENTIFICATION

Radiographic image should permit differentiation between the various structures of the teeth, the

periodontal ligament space, the lamina dura, the supporting bone and normal anatomic

landmarks.

IMAGE COVERAGE

All crowns and roots, including apices, are fully depicted together with the interproximal

alveolar crests, contact areas, and surrounding bone regions.

IMAGE DEFECTS

Images of all teeth and other structures are shown in proper relative size and contour with

minimal distortion, without overlapping images where anatomically possible, and without partial

images (cone cuts).

ANATOMICAL ACCURACY

A properly exposed radiograph is said to have anatomical accuracy when:

1. The labial and lingual cemento-enamel junctions of the anterior teeth are superimposed.

2. The buccal and lingual cusps of posterior teeth (especially the molars) are superimposed.

3. The contacts of the teeth are opened in at least one of the projections of a given area.

4. The buccal portion of the alveolar crest is superimposed over the lingual portion of the

alveolar crest.

5. There is no superimposition of the zygomatic bone over the roots of the maxillary molar

teeth.

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EACH SPECIFIC REGION OF THE FMX SHOULD INCLUDE THE FOLLOWING:

Maxillary molar area

All crowns and roots of the maxillary molars including the apices are fully depicted together

with the interproximal alveolar crests, contact areas and surrounding bone region. There is no

superimposition of the lower border of the zygomatic bone over the roots of maxillary molars.

The radiograph should include all of the first, second, and third molars (erupted or not) with open

interproximal spaces.

Maxillary premolar area

All the crowns and roots of the maxillary premolars and first molar, including the apices, are

fully depicted together with interproximal alveolar crests, contact areas and surrounding bone. In

the maxillary premolar projection the distal surface (distal 1/2) of the canine must be seen. The

contacts should be open.

Maxillary canine area

All of the crown and root of the maxillary canine, including the apex, is fully depicted together

with the interproximal alveolar crest between the maxillary canine and the maxillary lateral

incisor, the contact area and surrounding bone region. The lateral incisor - canine contact should

be open but it is not necessary for the distal surface of the maxillary canine to be seen. The

canine should be centered.

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Maxillary central - lateral incisor area

The central-lateral contact should be centered and open. The crowns and roots should be visible

with at least 2 mm of bone visible beyond the apex.

Mandibular molar area

All crowns and roots, including apices, of all three mandibular molars, are fully depicted

together with interproximal alveolar crests, contact areas and surrounding bone regions. Contacts

should be open.

Mandibular premolar area

All the crowns and roots of the mandibular premolars, including the apices, are fully depicted

together with interproximal alveolar crests, contact areas and surrounding bone regions. The

distal surface (distal1/2) of the canine should be seen in this projection. Contacts should be open.

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Mandibular canine area

All of the crown and the root of the mandibular canine, including the apex, is fully depicted

together with the interproximal alveolar crests and contact area between the mandibular lateral

incisor and mandibular canine, and surrounding bone region. The canine should be centered.

Lateral-canine contact should be open.

Mandibular central - lateral incisor area

All crowns and roots, including apices, of the central and lateral incisors, are fully depicted

together with interproximal alveolar crests, contact areas and surrounding bone regions. The

central - lateral incisor contact should be centered in the radiograph and should be open.

Premolar bitewing

All crowns of the maxillary and mandibular premolars are fully depicted together with the

interproximal crests and contact areas. The distal surfaces of the maxillary and mandibular

canines must be seen. The images are without horizontal overlap where anatomically possible.

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Molar bitewing

All crowns of the maxillary and mandibular molars are fully depicted together with the

interproximal crests and contact areas. It is preferable to see the distal surfaces of the maxillary

and mandibular second premolar teeth. The images are without horizontal overlap where

anatomically possible. The distal of the last erupted tooth is visible.

RADIOGRAPHIC MOUNTING PROCEDURES

Mounting intraoral radiographs is a relatively simple procedure provided you have some

knowledge of the normal radiographic anatomical landmarks for each region of the mouth and

can recognize tooth morphology.

Maxillary posterior regions:

All maxillary posterior radiographs should be arranged so that the crowns of the teeth are

toward the bottom of the computer screen and roots are towards the top (the same way they are

positioned within the patient). If no radiographs were exposed backwards, once the

maxillary posterior radiographs are oriented with the crowns downward, it will be necessary

only to identify mesial or distal anatomic landmarks of teeth in order to distinguish right from

left. Radiographs with the more mesial structures are mounted in the premolar position; those

with more distal landmarks are mounted in the molar positions.

Maxillary anterior region:

Identify the four maxillary anterior radiographs and rotate the incisal portion of each image

down toward the bottom of the computer screen (same as for maxillary posterior region). Use

the anatomic landmarks of the nasal cavity, soft tissue of the nose, and maxillary sinus to help

you distinguish between the maxillary and mandibular anterior periapical radiographs.

Identify the maxillary central - lateral incisor radiographs and mount them in the center

windows of the anterior section of the mount; next identify the R and L canine radiographs and

mount them with mesial anatomic structures always directed toward the middle of the mount.

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Mandibular posterior regions:

Identify the four (4) posterior mandibular radiographs. Rotate these radiographs around until

the coronal portion of the radiograph is directed toward the top of the computer screen. Identify

mesial and distal structures and arrange in appropriate areas of the mount.

Mandibular anterior region:

Rotate the four mandibular anterior radiographs until their incisal edges are directed toward the

top of the screen; identify the central - lateral incisor regions and mount them into the center

windows of the mount. Next mount the canine projections.

Bitewings:

The remaining four radiographs are interproximal radiographs. Orient these radiographs with

the curve of Spee (occlusal plane between maxillary and mandibular teeth) directed upward

toward the distal. If the occlusal plane is flat attempt to identify characteristics of the respective

crowns or frequently the bifurcation of the mandibular molar is distinguishable and may serve

as a valuable aid in distinguishing mandibular from maxillary teeth. Once the appropriate arch

can be identified the radiographs can be properly oriented with the most mesial structures used

to identify right from left and premolar from molar regions.

PATIENT'S RIGHT PATIENT'S LEFT

Ex. mounted FMX

intraoral radiographic technique manual radiographic technique manual utilizing the paralleling...

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