Intraoral Radiography Chapter 41 Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved

Intraoral Intraoral RadiographyRadiography

Chapter 41Chapter 41

Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved.


Lesson 41.1Lesson 41.1


Pronounce, define, and spell the Key Terms.Pronounce, define, and spell the Key Terms. Explain the advantages and disadvantages of the Explain the advantages and disadvantages of the

paralleling and bisecting techniques.paralleling and bisecting techniques. Name the two primary types of projections used in Name the two primary types of projections used in

an intraoral technique and describe the an intraoral technique and describe the differences.differences.

Explain the basic principle of the paralleling Explain the basic principle of the paralleling technique.technique.

State the five basic rules of the paralleling State the five basic rules of the paralleling technique.technique.

(Cont’d)(Cont’d)

Learning ObjectivesLearning Objectives



Explain why a film holder is necessary with Explain why a film holder is necessary with the paralleling technique. the paralleling technique.

Describe how to prepare a patient for dental Describe how to prepare a patient for dental x-rays.x-rays.

Expose a full series of radiographs using the Expose a full series of radiographs using the paralleling technique.paralleling technique.

Label and identify the parts of the Rinn XCP Label and identify the parts of the Rinn XCP (extension-cone paralleling) instruments.(extension-cone paralleling) instruments.



IntroductionIntroduction

It is possible for every dental assistant to successfully produce quality dental radiographs—radiographs that are free from distortion, with the

correct density and contrast, that can be used in the detection of dental disease. You can create such

radiographs by carefully following the proper steps in film placement, exposure, and processing.


Fig. 41-1 Steps to quality radiographs.Fig. 41-1 Steps to quality radiographs.


Full-Mouth SurveyFull-Mouth Survey

No dental examination is complete without No dental examination is complete without dental radiographs, and in almost all cases dental radiographs, and in almost all cases the full-mouth survey is the most preferred the full-mouth survey is the most preferred technique. technique.

An intraoral full-mouth examination (FMX) An intraoral full-mouth examination (FMX) contains both periapical and bite-wing contains both periapical and bite-wing radiographs.radiographs.


The FMXThe FMX

An intraoral FMX is composed of both An intraoral FMX is composed of both periapical and bite-wing projections. periapical and bite-wing projections.

This technique requires the use of intraoral This technique requires the use of intraoral film, which is placed inside the mouth and is film, which is placed inside the mouth and is used to examine the teeth and supporting used to examine the teeth and supporting structures. structures.

In the average adult, a full-mouth series In the average adult, a full-mouth series consists of 18 to 20 films. Generally there are consists of 18 to 20 films. Generally there are 14 periapicals and 4 to 6 bite-wings, but the 14 periapicals and 4 to 6 bite-wings, but the number may vary.number may vary.


Fig. 41-4 Mounted full-mouth series with eight Fig. 41-4 Mounted full-mouth series with eight anterior films, taken with the use of the parallel technique.anterior films, taken with the use of the parallel technique.


The Bite-Wing RadiographThe Bite-Wing Radiograph

The bite-wing radiograph shows the upper The bite-wing radiograph shows the upper and lower teeth in occlusion.and lower teeth in occlusion.

Only the crowns and a small portion of the Only the crowns and a small portion of the root of the teeth are seen. root of the teeth are seen.

It is used for to detect interproximal decay, It is used for to detect interproximal decay, periodontal disease, and recurrent decay periodontal disease, and recurrent decay under restorations and to assess the fit of under restorations and to assess the fit of metallic fillings or crowns.metallic fillings or crowns.


Fig. 41-2 Bite-wing radiograph. Note that only the crowns and Fig. 41-2 Bite-wing radiograph. Note that only the crowns and alveolar ridge, not the roots, are visible.alveolar ridge, not the roots, are visible.


The Periapical RadiographThe Periapical Radiograph

The periapical radiograph shows the entire The periapical radiograph shows the entire tooth from occlusal surface or incisal edge to tooth from occlusal surface or incisal edge to 2 to 3 mm beyond the apex to show the 2 to 3 mm beyond the apex to show the periapical bone. periapical bone.

The periapical is used to diagnose pathologic The periapical is used to diagnose pathologic conditions of the tooth, root, and bone, as conditions of the tooth, root, and bone, as well as tooth formation and eruption.well as tooth formation and eruption.

Periapical views are essential in endodontic Periapical views are essential in endodontic and oral surgery procedures.and oral surgery procedures.


Fig. 41-3 A, Anterior periapical.Fig. 41-3 A, Anterior periapical.


Fig. 41-3 B, Posterior periapical. Note that the entire tooth and Fig. 41-3 B, Posterior periapical. Note that the entire tooth and surrounding bone are visible in the radiograph.surrounding bone are visible in the radiograph.


Introduction to TechniquesIntroduction to Techniques

There are two basic techniques for obtaining There are two basic techniques for obtaining periapical radiographs:periapical radiographs: ParallelingParalleling Bisection of the angleBisection of the angle

The American Academy of Oral and Maxillofacial The American Academy of Oral and Maxillofacial Radiology and the American Association of Dental Radiology and the American Association of Dental Schools recommend the use of the paralleling Schools recommend the use of the paralleling technique because it provides the most accurate technique because it provides the most accurate image.image.

In some situations the operator may have to use In some situations the operator may have to use the bisection technique.the bisection technique.


The Paralleling Technique: Basic The Paralleling Technique: Basic RulesRules

Film placement: Position the film so that it will cover the Film placement: Position the film so that it will cover the teeth. teeth.

Film position: Position the film parallel to the long axis of the Film position: Position the film parallel to the long axis of the tooth. The film in the film holder must be placed away from tooth. The film in the film holder must be placed away from the teeth and toward the middle of the mouth. the teeth and toward the middle of the mouth.

Vertical angulation: Direct the central ray of the x-ray beam Vertical angulation: Direct the central ray of the x-ray beam perpendicular to the film and the long axis of the tooth. perpendicular to the film and the long axis of the tooth.

Horizontal angulation: Direct the central ray Horizontal angulation: Direct the central ray of the x-ray beam through the contact areas between the of the x-ray beam through the contact areas between the teeth. teeth.

Central ray: Center the x-ray beam on the film Central ray: Center the x-ray beam on the film to ensure that all areas of the film are exposed. to ensure that all areas of the film are exposed.


Tips for Film Placement Tips for Film Placement

The white side of the film always faces the teeth. The white side of the film always faces the teeth. Anterior films are always placed vertically. Anterior films are always placed vertically. Posterior films are always placed horizontally. Posterior films are always placed horizontally. The identification dot on the film is always placed in The identification dot on the film is always placed in

the slot of the film holder (“dot in the slot”). the slot of the film holder (“dot in the slot”). Always position the film holder away from the teeth Always position the film holder away from the teeth

and toward the middle of the mouth. and toward the middle of the mouth. Always center the film over the areas to be Always center the film over the areas to be

examined. examined. Always place the film parallel to the long axis of the Always place the film parallel to the long axis of the

teeth. teeth.


Fig. 41-8 Position of the film, teeth, position-indicator device (Fig. 41-8 Position of the film, teeth, position-indicator device (PIDPID), ), and central ray of the x-ray beam in the paralleling technique. and central ray of the x-ray beam in the paralleling technique.

(From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, , ed 3, St Louis, 2006, Saunders.)St Louis, 2006, Saunders.)


Fig. 41-9 The x-rays pass through the contact areas of the premolars because the Fig. 41-9 The x-rays pass through the contact areas of the premolars because the central ray is directed through the contacts and perpendicular to the film.central ray is directed through the contacts and perpendicular to the film. If the central ray (CR) is not directed through the contacts, overlap of the If the central ray (CR) is not directed through the contacts, overlap of the

premolar contacts occurs.premolar contacts occurs. (From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques, ed 3, , ed 3,

St Louis, 2006, Saunders.)St Louis, 2006, Saunders.)


Fig. 41-10 This radiograph demonstrates a cone cut—Fig. 41-10 This radiograph demonstrates a cone cut—that is, a clear exposed area on the film. that is, a clear exposed area on the film.

(From (From Iannucci J, Jansen Howerton L: Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, , ed 3, St Louis, 2006, Saunders.)St Louis, 2006, Saunders.)


Preparation Before Seating Preparation Before Seating the Patient the Patient

Prepare the operatory with all infection-control barriers. Prepare the operatory with all infection-control barriers. Determine the number and type of films to be exposed.Determine the number and type of films to be exposed. Label a paper cup with the patient's name and the Label a paper cup with the patient's name and the

date. date. This is the transfer cup for storing and moving exposed films.This is the transfer cup for storing and moving exposed films.

Turn on the x-ray machine and check the basic Turn on the x-ray machine and check the basic settings.settings.

Wash and dry your hands. Wash and dry your hands. Dispense the desired number of films and store them Dispense the desired number of films and store them

outside the room in which the x-ray machine is being outside the room in which the x-ray machine is being used. used.


Positioning the Patient Positioning the Patient

Seat the patient comfortably in the dental chair, with the Seat the patient comfortably in the dental chair, with the back in an upright position and the head supported. back in an upright position and the head supported.

Ask the patient to remove eyeglasses and bulky earrings. Ask the patient to remove eyeglasses and bulky earrings. Have the patient take any removable prosthetic Have the patient take any removable prosthetic

appliances out of his or her mouth.appliances out of his or her mouth. Position the patient with the occlusal plane of the jaw Position the patient with the occlusal plane of the jaw

being radiographed parallel to the floor when the mouth being radiographed parallel to the floor when the mouth is in the open position. is in the open position.

Drape the patient with a lead apron and thyroid collar. Drape the patient with a lead apron and thyroid collar. Wash and dry your hands and put on clean examination Wash and dry your hands and put on clean examination

gloves. gloves.


The Exposure Sequence The Exposure Sequence

When exposing radiographs, establish an When exposing radiographs, establish an exposure sequence, or definite order, for exposure sequence, or definite order, for periapical film placement.periapical film placement.

Without an exposure sequence, there is a Without an exposure sequence, there is a good chance that you will omit an area or good chance that you will omit an area or expose the same area twice. expose the same area twice.


The Anterior Exposure Sequence The Anterior Exposure Sequence

When exposing periapical films with the When exposing periapical films with the paralleling technique, always start with the paralleling technique, always start with the anterior teeth (canines and incisors), because: anterior teeth (canines and incisors), because: The size 1 film used for anteriors is small, less The size 1 film used for anteriors is small, less

uncomfortable, and easier for the patient to tolerate. uncomfortable, and easier for the patient to tolerate. It is easier for the patient to become accustomed to It is easier for the patient to become accustomed to

the anterior film holder. the anterior film holder. The anterior film placements are less likely to cause The anterior film placements are less likely to cause

the patient to gag. the patient to gag. (Cont’d)(Cont’d)


The Anterior Exposure SequenceThe Anterior Exposure Sequence


Begin with the maxillary right canine (tooth 6). Begin with the maxillary right canine (tooth 6). Expose all of the maxillary anterior teeth from right to Expose all of the maxillary anterior teeth from right to

left. left. End with the maxillary left canine (tooth 11). End with the maxillary left canine (tooth 11). Next, move to the mandibular arch. Next, move to the mandibular arch. Begin with the mandibular left canine (tooth 22). Begin with the mandibular left canine (tooth 22). Expose all of the mandibular anterior teeth from left Expose all of the mandibular anterior teeth from left

to right. to right. Finish with the mandibular right canine (tooth 27).Finish with the mandibular right canine (tooth 27).


The Maxillary Canine Region The Maxillary Canine Region

Insert the number 1 film packet vertically into Insert the number 1 film packet vertically into the anterior bite-block. the anterior bite-block.

Position the film packet with the canine and Position the film packet with the canine and first premolar centered. Position the film as first premolar centered. Position the film as far to the posterior as possible. far to the posterior as possible.

With the film-holding instrument and film in With the film-holding instrument and film in place, instruct the patient to close his or her place, instruct the patient to close his or her mouth slowly but firmly. mouth slowly but firmly.

Position the localizing ring and PID, then Position the localizing ring and PID, then expose the film. expose the film.


Maxillary Central/Lateral Incisor Maxillary Central/Lateral Incisor Region Region

Insert the number 1 film packet vertically into Insert the number 1 film packet vertically into the anterior bite-block. the anterior bite-block.

Center the film packet between the central Center the film packet between the central and lateral incisors and position the film as far and lateral incisors and position the film as far to the posterior as possible. to the posterior as possible.

With the film-holding instrument and film in With the film-holding instrument and film in place, instruct the patient to close his or place, instruct the patient to close his or mouth slowly but firmly. mouth slowly but firmly.



The Mandibular Canine Region The Mandibular Canine Region

Insert the number 1 film packet vertically into Insert the number 1 film packet vertically into the anterior bite-block.the anterior bite-block.

Center the film on the canine. Position the Center the film on the canine. Position the film as far in the lingual direction as the film as far in the lingual direction as the patient’s anatomy will allow. patient’s anatomy will allow.

A cotton roll may be placed between the A cotton roll may be placed between the maxillary teeth and bite-block to prevent maxillary teeth and bite-block to prevent rocking of the bite-block on the canine tip and rocking of the bite-block on the canine tip and to increase patient comfort. to increase patient comfort.


The Mandibular Canine RegionThe Mandibular Canine Region


The Mandibular Incisor Region The Mandibular Incisor Region

Insert the number 1 film packet vertically into the Insert the number 1 film packet vertically into the anterior bite-block. anterior bite-block.

Center the film packet between the central and Center the film packet between the central and lateral incisors and position the film as far in the lateral incisors and position the film as far in the lingual direction as the patient's anatomy will lingual direction as the patient's anatomy will allow. allow.

With the instrument and film in place, instruct the With the instrument and film in place, instruct the patient to close his or her mouth slowly but firmly. patient to close his or her mouth slowly but firmly.

Position the localizing ring and PID, then expose Position the localizing ring and PID, then expose the film. the film.


Mandibular Incisor RegionMandibular Incisor Region


The Posterior Exposure Sequence The Posterior Exposure Sequence

After completing the anterior teeth, begin the After completing the anterior teeth, begin the posterior teeth.posterior teeth.

Always expose the premolar film before the Always expose the premolar film before the molar film because: molar film because: Premolar film placement is easier for the patient to Premolar film placement is easier for the patient to

tolerate than molar film placement. tolerate than molar film placement. Premolar exposure is less likely to evoke the gag Premolar exposure is less likely to evoke the gag

reflex. reflex.


The Maxillary Premolar Region The Maxillary Premolar Region

Insert the film packet horizontally into the Insert the film packet horizontally into the posterior bite-block, pushing the film packet all posterior bite-block, pushing the film packet all the way into the slot.the way into the slot.

Center the film packet on the second premolar. Center the film packet on the second premolar. Position the film in the midpalate area. Position the film in the midpalate area.

With the instrument and film in place, instruct With the instrument and film in place, instruct the patient to close his or her mouth slowly but the patient to close his or her mouth slowly but firmly. firmly.



The Maxillary Premolar RegionThe Maxillary Premolar Region


The Maxillary Molar Region The Maxillary Molar Region

Insert the film packet horizontally into the Insert the film packet horizontally into the posterior bite-block. posterior bite-block.

Center the film packet on the second molar. Center the film packet on the second molar. Position the film in the midpalate area. Position the film in the midpalate area.

With the instrument and film in place, instruct With the instrument and film in place, instruct the patient to close his or her mouth slowly the patient to close his or her mouth slowly but firmly. but firmly.

Position the localizing ring and PID, then Position the localizing ring and PID, then expose the radiograph. expose the radiograph.


The Maxillary Molar RegionThe Maxillary Molar Region


The Mandibular Premolar Region The Mandibular Premolar Region

Insert the number 2 film horizontally into the posterior Insert the number 2 film horizontally into the posterior bite-block. bite-block.

Center the film on the contact point between the Center the film on the contact point between the second premolar and first molar. Position the film as far second premolar and first molar. Position the film as far in the lingual direction as the patient's anatomy will in the lingual direction as the patient's anatomy will allow. allow.


Slide the localizing ring down the indicator rod to the Slide the localizing ring down the indicator rod to the patient's skin. patient's skin.

Position the localizing ring and PID, then expose the Position the localizing ring and PID, then expose the film. film.


The Mandibular Premolar RegionThe Mandibular Premolar Region


The Mandibular Molar RegionThe Mandibular Molar Region

Insert the number 2 film horizontally into the posterior Insert the number 2 film horizontally into the posterior bite-block. bite-block.

Center the film on the second molar. Position the film Center the film on the second molar. Position the film as far in the lingual direction as the tongue will allow. as far in the lingual direction as the tongue will allow. This position will be closer to the teeth than that for This position will be closer to the teeth than that for the premolar and anterior views. the premolar and anterior views.


Position the localizing ring and PID, then expose the Position the localizing ring and PID, then expose the film. film.


The Mandibular Molar RegionThe Mandibular Molar Region





Explain the procedural principles of the Explain the procedural principles of the bisecting technique.bisecting technique.

Identify the types of film holders that can be Identify the types of film holders that can be used with the bisecting technique.used with the bisecting technique.

Describe the appearance of opened and Describe the appearance of opened and overlapped contact areas on a dental overlapped contact areas on a dental radiograph.radiograph.

Describe the correct vertical angulation.Describe the correct vertical angulation.(Cont’d)(Cont’d)




Describe incorrect vertical angulation.Describe incorrect vertical angulation. Identify the film size used in the bisecting Identify the film size used in the bisecting

technique.technique. Expose a full series of radiographs using the Expose a full series of radiographs using the

bisecting angle technique.bisecting angle technique.



The Bisecting Technique The Bisecting Technique

The bisection of the angle technique is based The bisection of the angle technique is based on a geometric principle of bisecting a on a geometric principle of bisecting a triangle (bisecting means dividing into two triangle (bisecting means dividing into two equal parts).equal parts).

The angle formed by the long axis of the teeth The angle formed by the long axis of the teeth and the film is bisected, and the x-ray beam is and the film is bisected, and the x-ray beam is directed perpendicular to the bisecting line.directed perpendicular to the bisecting line.

““Perpendicular” means at a right angle to the Perpendicular” means at a right angle to the film.film.


Fig. 41-13 A, A diagram of an anterior tooth with the central ray perpendicular to Fig. 41-13 A, A diagram of an anterior tooth with the central ray perpendicular to the “imaginary” bisector of the angle between the long axis of the tooth and the the “imaginary” bisector of the angle between the long axis of the tooth and the

film plane. B, A posterior tooth using the bisecting-angle concept. film plane. B, A posterior tooth using the bisecting-angle concept. (From Miles D, et al: (From Miles D, et al: Radiographic imaging for dental auxiliariesRadiographic imaging for dental auxiliaries, ed 3, Philadelphia, 1999, Saunders.), ed 3, Philadelphia, 1999, Saunders.)

A B


Film Holders Film Holders

Although you may see operators asking patients Although you may see operators asking patients to hold the film with their fingers to stabilize the to hold the film with their fingers to stabilize the film in the mouth, it is not recommended. This film in the mouth, it is not recommended. This practice exposes the patient’s hand and finger practice exposes the patient’s hand and finger to unnecessary radiation. to unnecessary radiation.

The following are types of commercial film The following are types of commercial film holders that are available: holders that are available: Rinn BAI Rinn BAI Rinn Eezee-Grip Film Holder (Snap-A-Ray)Rinn Eezee-Grip Film Holder (Snap-A-Ray) Rinn Stabe Bite-BlockRinn Stabe Bite-Block


PID Angulations: Bisecting PID Angulations: Bisecting TechniqueTechnique

In the bisecting technique, the angulation of In the bisecting technique, the angulation of the PID is critical. the PID is critical.

Angulation is a term used to describe the Angulation is a term used to describe the alignment of the central ray of the x-ray beam alignment of the central ray of the x-ray beam in the horizontal and vertical planes. in the horizontal and vertical planes.

Angulation can be changed by moving the Angulation can be changed by moving the PID in either a horizontal or vertical direction. PID in either a horizontal or vertical direction.

BAIs with aiming rings dictate the proper PID BAIs with aiming rings dictate the proper PID angulation.angulation.


Horizontal AngulationHorizontal Angulation

Horizontal angulation refers to the positioning Horizontal angulation refers to the positioning of the tubehead and direction of the central of the tubehead and direction of the central ray in a horizontal, or side-to-side, plane. ray in a horizontal, or side-to-side, plane.

The horizontal angulation remains the same The horizontal angulation remains the same whether you are using the paralleling or whether you are using the paralleling or bisecting technique.bisecting technique.


Fig. 41-15 The arrows indicate movement in a horizontal Fig. 41-15 The arrows indicate movement in a horizontal direction.direction.


Correct Horizontal AngulationCorrect Horizontal Angulation

With correct horizontal angulation, the central With correct horizontal angulation, the central ray is directed perpendicular to the curvature ray is directed perpendicular to the curvature of the arch and through the contact areas of of the arch and through the contact areas of the teeth. the teeth.

Incorrect horizontal angulation results in Incorrect horizontal angulation results in overlapped (unopened) contact areas. overlapped (unopened) contact areas.

A film with overlapped contact areas cannot A film with overlapped contact areas cannot be used to examine the interproximal areas of be used to examine the interproximal areas of the teeth. the teeth.


Fig. 41-16 Correct horizontal angulation. Fig. 41-16 Correct horizontal angulation. (From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques, ed 3, , ed 3,



Fig. 41-17 Incorrect horizontal angulation. Fig. 41-17 Incorrect horizontal angulation. (From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques, ed 3, , ed 3,



Fig. 41-18 Overlapped contact areas.Fig. 41-18 Overlapped contact areas.


Vertical Angulation Vertical Angulation

Vertical angulation refers to the positioning of the Vertical angulation refers to the positioning of the PID in a vertical, or up-and-down, plane.PID in a vertical, or up-and-down, plane.

The vertical angulation differs depending on the The vertical angulation differs depending on the radiographic technique being used: radiographic technique being used: With the paralleling technique, the vertical angulation With the paralleling technique, the vertical angulation

of the central ray is directed perpendicular to the film of the central ray is directed perpendicular to the film and the long axis of the tooth. and the long axis of the tooth.

With the bisecting technique, the vertical angulation is With the bisecting technique, the vertical angulation is determined by the imaginary bisector; the central ray determined by the imaginary bisector; the central ray is directed perpendicular to the imaginary bisector. is directed perpendicular to the imaginary bisector.


Fig. 41-19 Vertical angulation of the PIDFig. 41-19 Vertical angulation of the PIDrefers to PID placement in an up-and-down (head-to-toe) refers to PID placement in an up-and-down (head-to-toe)

direction.direction.


Correct Vertical Angulation Correct Vertical Angulation

Correct vertical angulation results in a Correct vertical angulation results in a radiographic image that is the same length as radiographic image that is the same length as the tooth. the tooth.

Incorrect vertical angulation results in an Incorrect vertical angulation results in an image that is not the same length as the tooth image that is not the same length as the tooth being radiographed. being radiographed.

The image appears longer or shorter: The image appears longer or shorter: Elongated Elongated Foreshortened Foreshortened


Fig. 41-20 A, If the vertical angulation is to too steep, the image Fig. 41-20 A, If the vertical angulation is to too steep, the image on the film is shorter than the actual tooth. B, Foreshortened images.on the film is shorter than the actual tooth. B, Foreshortened images.

(From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques, ed 3, , ed 3, St Louis, 2006, Saunders.)St Louis, 2006, Saunders.)


Fig. 41-21 A, If the vertical angulation is to too flat, the image on Fig. 41-21 A, If the vertical angulation is to too flat, the image on the film is longer than the actual tooth. B, Elongated images. the film is longer than the actual tooth. B, Elongated images.

(From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques, ed 3, , ed 3, St Louis, 2006, Saunders.)St Louis, 2006, Saunders.)

A

B


Film Size and Placement Film Size and Placement

In the bisection technique, the film is placed In the bisection technique, the film is placed close to the crowns of the teeth to be close to the crowns of the teeth to be radiographed and extends at an angle into radiographed and extends at an angle into the palate or floor of the mouth.the palate or floor of the mouth.

The film packet should extend beyond the The film packet should extend beyond the incisal or occlusal aspect of the teeth by incisal or occlusal aspect of the teeth by about 1/8 to 1/4 inch.about 1/8 to 1/4 inch.

Film holders for the bisection of the angle Film holders for the bisection of the angle technique, including some with alignment technique, including some with alignment indicators, are available commercially. indicators, are available commercially.


Beam Alignment Beam Alignment

The x-ray beam is directed to pass between the The x-ray beam is directed to pass between the contacts of the teeth being radiographed in the contacts of the teeth being radiographed in the horizontal dimension, just as it does in the paralleling horizontal dimension, just as it does in the paralleling technique. technique.

The vertical angle, however, must be directed at a 90-The vertical angle, however, must be directed at a 90-degree angle to the imaginary bisecting line.degree angle to the imaginary bisecting line.

Too much vertical angulation will produce images that Too much vertical angulation will produce images that are foreshortened. are foreshortened.

Too little vertical angulation will result in images that Too little vertical angulation will result in images that are elongated. are elongated.

The beam must be centered to help prevent cone The beam must be centered to help prevent cone cutting. cutting.


Maxillary Canine ExposureMaxillary Canine Exposure


Maxillary Incisor ExposureMaxillary Incisor Exposure


Mandibular Canine ExposureMandibular Canine Exposure


Mandibular Incisor ExposureMandibular Incisor Exposure


Maxillary Premolar ExposureMaxillary Premolar Exposure


Maxillary Molar ExposureMaxillary Molar Exposure (Patient photo from Iannucci J, Jansen Howerton L: (Patient photo from Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, , ed 3,



Mandibular Premolar ExposureMandibular Premolar Exposure(Patient photo from Iannucci J, Jansen Howerton L: (Patient photo from Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, , ed 3,



Mandibular Molar ExposureMandibular Molar Exposure (Patient photo from Iannucci J, Jansen Howerton L: (Patient photo from Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, , ed 3,






Explain the basic rules for the bite-wing Explain the basic rules for the bite-wing technique.technique.

Explain the recommended vertical angulation Explain the recommended vertical angulation for all bite-wing exposures.for all bite-wing exposures.

Expose and mount a series of bite-wing Expose and mount a series of bite-wing radiographs.radiographs.

Explain the technique for exposing occlusal Explain the technique for exposing occlusal radiographs.radiographs.





Expose a maxillary and mandibular occlusal Expose a maxillary and mandibular occlusal radiograph. radiograph.

Describe techniques for managing patients Describe techniques for managing patients with physical and mental disabilities.with physical and mental disabilities.

Describe techniques for managing the patient Describe techniques for managing the patient with a hypersensitive gag reflex.with a hypersensitive gag reflex.

Mount and label a full series of dental Mount and label a full series of dental radiographs.radiographs.



Bite-Wing Examinations Bite-Wing Examinations

A bite-wing radiograph shows the crowns and A bite-wing radiograph shows the crowns and interproximal areas of the maxillary and interproximal areas of the maxillary and mandibular teeth and the areas of crestal bone on mandibular teeth and the areas of crestal bone on one film. one film.

Bite-wing radiographs are used to detect Bite-wing radiographs are used to detect interproximal caries (tooth decay) and are interproximal caries (tooth decay) and are particularly useful in detecting early carious particularly useful in detecting early carious lesions that are not clinically evident. lesions that are not clinically evident.

Bite-wing radiographs are also useful in Bite-wing radiographs are also useful in examining the crestal bone levels between examining the crestal bone levels between the teeth.the teeth.


Basic Principles of Basic Principles of the Bite-Wing Technique the Bite-Wing Technique

The film is placed in the mouth parallel to the The film is placed in the mouth parallel to the crowns of both the upper and lower teeth. crowns of both the upper and lower teeth.

The film is stabilized when the patient bites The film is stabilized when the patient bites on the bite-wing tab or bite-wing film holder. on the bite-wing tab or bite-wing film holder.

The central ray of the x-ray beam is directed The central ray of the x-ray beam is directed through the contacts of the teeth, using a through the contacts of the teeth, using a +10-degree vertical angulation. +10-degree vertical angulation.


Fig. 41-22Fig. 41-22 Vertical angulation of + Vertical angulation of +10 degrees 10 degrees is used to compensate is used to compensate for the slight bend of the upper portion of the film for the slight bend of the upper portion of the film

and the tilt of the maxillary teeth. and the tilt of the maxillary teeth. (From Iannucci J, Jansen Howerton L: (From Iannucci J, Jansen Howerton L: Dental radiography: principles and techniquesDental radiography: principles and techniques , ed 3, St Louis, 2006, Saunders.), ed 3, St Louis, 2006, Saunders.)


Fig. 41-23 Fig. 41-23 Bite-wing tab and film holder.Bite-wing tab and film holder.


Bite-Wing Film PlacementBite-Wing Film Placement

The film is positioned (with either a bite tab or a The film is positioned (with either a bite tab or a film-holding device) parallel to the crowns of both film-holding device) parallel to the crowns of both upper and lower teeth, and the central ray is upper and lower teeth, and the central ray is directed perpendicular to the film. directed perpendicular to the film.

The premolar bite-wing radiograph should include The premolar bite-wing radiograph should include the distal half of the crowns of the canines, both the distal half of the crowns of the canines, both premolars, and often the premolars, and often the first molars on both the maxillary and mandibular first molars on both the maxillary and mandibular arches. arches.

The molar bite-wing should be centered over the The molar bite-wing should be centered over the second molars. second molars.


Premolar bite-wing. A, Film placement. Premolar bite-wing. A, Film placement. B, Resultant radiograph.B, Resultant radiograph.

A B


Molar bite-wing. A, Film placement. B, Resultant radiograph.Molar bite-wing. A, Film placement. B, Resultant radiograph.

A B


The Occlusal TechniqueThe Occlusal Technique

The occlusal technique is used to examine The occlusal technique is used to examine large areas of the upper or lower jaw. large areas of the upper or lower jaw.

In the occlusal technique, size 4 intraoral film In the occlusal technique, size 4 intraoral film is used. The film is so named because the is used. The film is so named because the patient bites, or “occludes,” on the entire film.patient bites, or “occludes,” on the entire film.

In adults, size 4 film is used in the occlusal In adults, size 4 film is used in the occlusal examination. examination.

In children, size 2 film can be used. In children, size 2 film can be used.


Basic Principles of the Occlusal Basic Principles of the Occlusal TechniqueTechnique

The film is positioned with the white side The film is positioned with the white side facing the arch exposed. facing the arch exposed.

The film is placed in the mouth between the The film is placed in the mouth between the occlusal surfaces of the maxillary and occlusal surfaces of the maxillary and mandibular teeth. mandibular teeth.

The film is stabilized when the patient gently The film is stabilized when the patient gently bites on the surface of the film. bites on the surface of the film.


A, The central ray (A, The central ray (CRCR) is directed at an angle of +65 degrees to the plane ) is directed at an angle of +65 degrees to the plane of the film. B, Relationship of film and PID.of the film. B, Relationship of film and PID.

A B

+65°


Patients with Special Needs Patients with Special Needs

Radiographic examination techniques must Radiographic examination techniques must often be modified to accommodate patients often be modified to accommodate patients with special needs. with special needs.

The dental radiographer must be competent The dental radiographer must be competent in altering radiographic technique to meet the in altering radiographic technique to meet the specific diagnostic need of the individual specific diagnostic need of the individual patient. patient.


Physical Disabilities Physical Disabilities

A person with a physical disability may have A person with a physical disability may have problems with vision, hearing, or mobility. problems with vision, hearing, or mobility.

You must make every effort to meet the You must make every effort to meet the individual needs of such patients.individual needs of such patients.

In many cases, a family member or caretaker In many cases, a family member or caretaker accompanies the person with a physical accompanies the person with a physical disability to the dental office. disability to the dental office.

You can ask the caretaker to assist you in You can ask the caretaker to assist you in communicating with regard to the physical communicating with regard to the physical needs of the patient. needs of the patient.


Fig. 41-24 Fig. 41-24 Wheelchair-bound patient having x-rays taken.Wheelchair-bound patient having x-rays taken.


Patients with Special Dental Needs Patients with Special Dental Needs

Reasons for radiographs in the edentulous Reasons for radiographs in the edentulous patient:patient: To detect the presence of root tips, impacted To detect the presence of root tips, impacted

teeth, and lesions (cysts, tumors). teeth, and lesions (cysts, tumors). To identify objects embedded in bone. To identify objects embedded in bone. To observe the quantity and quality of bone that is To observe the quantity and quality of bone that is

present.present.


Exposure Techniques for Exposure Techniques for the Edentulous Patientthe Edentulous Patient

The radiographic examination of an edentulous patient The radiographic examination of an edentulous patient may include a panoramic radiograph, periapical may include a panoramic radiograph, periapical radiographs, or a combination of occlusal and radiographs, or a combination of occlusal and periapical radiographs.periapical radiographs.

Radiographic images must be made in all teeth-bearing Radiographic images must be made in all teeth-bearing areas of the mouth, whether or not teeth are present.areas of the mouth, whether or not teeth are present.

In edentulous patients, either bisection of the angle or In edentulous patients, either bisection of the angle or the paralleling technique may be used.the paralleling technique may be used.

Because there are no teeth present, the distortion Because there are no teeth present, the distortion inherent in the bisecting technique does not interfere inherent in the bisecting technique does not interfere with the diagnostic intrabony conditions. with the diagnostic intrabony conditions.


Fig. 41-25 Fig. 41-25 Mixed occlusal-periapical edentulous survey.Mixed occlusal-periapical edentulous survey.


Radiographs in the Pediatric PatientRadiographs in the Pediatric Patient

In children, radiographs are useful in detecting In children, radiographs are useful in detecting conditions of the teeth and bones, in showing changes conditions of the teeth and bones, in showing changes related to caries and trauma, and in evaluating growth related to caries and trauma, and in evaluating growth and development.and development.

Explain the radiographic procedures you are about to Explain the radiographic procedures you are about to perform in terms that the child can easily understand. perform in terms that the child can easily understand. For example, you can refer to the tubehead as a For example, you can refer to the tubehead as a camera, the lead apron as a coat, and the radiograph camera, the lead apron as a coat, and the radiograph as a picture. as a picture.

Exposure factors (milliamperage, kilovoltage, time) Exposure factors (milliamperage, kilovoltage, time) must be reduced because of the smaller size of the must be reduced because of the smaller size of the pediatric patient.pediatric patient.


Fig. 41-26 Fig. 41-26 XCP instruments can also be used for the XCP instruments can also be used for the pediatric patient, but the exposure time is reduced.pediatric patient, but the exposure time is reduced.


Radiographs for the Endodontic Radiographs for the Endodontic PatientPatient

It often is difficult to obtain accurate radiographs It often is difficult to obtain accurate radiographs during endodontic (root canal) treatment because during endodontic (root canal) treatment because of the rubber dam clamp, endodontic instruments, of the rubber dam clamp, endodontic instruments, or filling material extending from the tooth. or filling material extending from the tooth.

The Endoray II film holder can be used to aid in The Endoray II film holder can be used to aid in positioning the film during this portion of the root positioning the film during this portion of the root canal procedure. canal procedure.

This holder fits around a rubber dam clamp and This holder fits around a rubber dam clamp and allows space for endodontic instruments and filling allows space for endodontic instruments and filling materials to protrude from the tooth. materials to protrude from the tooth.


Fig. 41-27 Endoray II film holder.Fig. 41-27 Endoray II film holder.


The Patient Who Gags The Patient Who Gags

To help prevent the gag reflex, you must convey To help prevent the gag reflex, you must convey a confident attitude.a confident attitude.

In a patient with a hypersensitive gag reflex, you In a patient with a hypersensitive gag reflex, you should expose the maxillary molars last. should expose the maxillary molars last.

When you place films in the maxillary posterior, When you place films in the maxillary posterior, do not slide them along the palate.do not slide them along the palate.

There may be times when you will encounter a There may be times when you will encounter a patient with an uncontrollable gag reflex. patient with an uncontrollable gag reflex.

When this occurs, you must use extraoral When this occurs, you must use extraoral radiographs such as panoramic or lateral jaw radiographs such as panoramic or lateral jaw radiographs. radiographs.


Normal Anatomic LandmarksNormal Anatomic Landmarks

To correctly mount dental radiographs, the To correctly mount dental radiographs, the dental assistant must be able to recognize dental assistant must be able to recognize the normal anatomic landmarks on intraoral the normal anatomic landmarks on intraoral radiographs.radiographs.


Maxillary Anterior LandmarksMaxillary Anterior Landmarks

Median palatine sutureMedian palatine suture Incisive foramenIncisive foramen Anterior nasal spineAnterior nasal spine Nasal septumNasal septum Nasal fossaNasal fossa


Landmarks of the MandibleLandmarks of the Mandible

Genial tuberclesGenial tubercles Lingual foramenLingual foramen Nutrient canalsNutrient canals Mandibular canalMandibular canal Coronoid processCoronoid process Mylohyoid ridgeMylohyoid ridge External oblique ridgeExternal oblique ridge Mental ridgeMental ridge


Tips for Mounting RadiographsTips for Mounting Radiographs

Handle films only by the edges.Handle films only by the edges. Label and date the film mount before Label and date the film mount before

mounting the films. mounting the films. Include the patient’s full name and date of Include the patient’s full name and date of

exposure and the dentist’s name. exposure and the dentist’s name. Work with clean, dry hands.Work with clean, dry hands. Use a definite order for mounting films.Use a definite order for mounting films. Use the “smile” line to mount bite-wing Use the “smile” line to mount bite-wing

radiographs. radiographs.


Documents

Intraoral Radiography Chapter 41 Copyright © 2009, 2006 by Saunders, an imprint of Elsevier Inc. All rights reserved