caries perio localization

Caries

Bitewing Film primarily

Periapical film also used

Low kVp, high contrast

(short scale)

Approximately 50 % demineralization is required for radiographic detection of a lesion. As seen in the occlusal view, above right, the thickness of the tooth buccolingually masks the carious lesion when it is small.

The actual depth of penetration of a carious lesion is deeper clinically than radiographically.

Proximal caries susceptible zone (between contact and free gingival margin)

caries

Factors affecting caries diagnosis:

Buccolingual thickness of tooth

Two-dimensional film

X-ray beam angle

Exposure factors

Radiographic Caries

I

M = Moderate I = Incipient

A = AdvancedS = Severe

S

AMA

Usually not restored unless patient has high caries activity

IncipientInterproximalCaries I

Up to half the thickness of enamel

Incipient

ModerateInterproximalCaries M

More than half-way through the enamel (up to DEJ)

Moderate

AdvancedInterproximalCaries AA

From DEJ to half-way through the dentin

Advanced

IncipientModerateAdvanced

SevereInterproximalCaries

More than halfway through the dentin

S

Green arrows identify restorative problems: fx (1), overhang (2), open margin (3)

3

21

Severe

Severe

Anterior interproximal caries can usually be diagnosed by directing bright light through the contact areas.

Transillumination

Must have penetrated into dentin

Diagnosed from clinical exam

Sharp explorer may contribute to spread of caries

Occlusal Caries

Occlusal

Use clinical exam

Can’t determine depth

Buccal/Lingual Caries

Buccal/lingual

Older patients with recession or periodontitis

Xerostomia may be present

Root Caries

Root caries

Cervical Burnout

Root caries may be confused with cervical burnout (see below).

Cross-section(red line at right)

Radiolucency seen above left (arrow) disappears on periapical film of same tooth (above right).

Cervical burnout

Anterior Cervical Burnout

bone level

cervical burnout area

Cervical burnout in the anterior region due to gap between enamel (red arrows) and alveolar bone over root (blue arrows).

May be due to high caries rate, poor oral hygiene, failure to remove all the caries, defective restoration or a combination.

Recurrent Caries

Recurrent caries(red arrows)

Recurrent caries

Rampant Caries

Rapidly progressing caries usually found in children and teens with poor diet and inadequate oral hygiene

Found in head/neck radiation therapy patients with xerostomia

Fluoride used for control

Radiation Caries

Before radiation

1 year after radiation

Mach BandOptical illusion giving appearance of increased radiolucency at junction of differing tissue densities

Bitewings best for diagnosis. Some feel that paralleling PA’s are best.

Higher kVp recommended (long scale, low contrast).

Compare images from differentvisits (using same technique).

Periodontal Disease

Two-dimensional film with overlapping bony walls, superimposed roots

Clinical picture more advanced

Relationship of hard to soft tissues not evident

Limitation of Radiographs

Involvement:

LocalizedGeneralized

Periodontitis

Periodontitis

Normal Anatomy:

Alveolar crest corticated

1-1.5 mm from crest to CEJ

Parallel to line between CEJ’s

Crest is pointed anteriorly

Corticated alveolar crests

1-1.5 mm

CEJ

Alveolar crests morepointed anteriorly

Contributing Factors• Occlusal trauma• Open contacts• Overhangs, poor contours• Calculus• Post-extraction defects (interdental

col)• Systemic involvement (diabetes, blood disorders, hormonal changes, stress, AIDS)

Horizontal bone loss: Parallel to line drawn between adjacent CEJ’s

Vertical (Angular) bone loss: More bone destruction on interproximal aspect of one tooth than on the adjacent tooth

Gingivitis

No bone loss

No radiographic signs

Mild Adult Periodontitis

Loss of cortical density

Rounding off of junction between alveolar crest and lamina dura

Blunting of crest anteriorly

Mild adult periodontitis

Horizontal bone loss or vertical osseous defects

Total extent of bone loss not evident

May have slight mobility

Moderate Adult Periodontitis

Moderate adult periodontitis(red arrows point to calculus)

Moderate adult periodontitis

Severe Adult Periodontitis

Tooth mobility

Extensive horizontal bone loss or vertical osseousdefects

Furcation involvement

Severe adult periodontitis

Restorative Materials• According to radiographic density beginning

with most radiopaque• Group I. Gold alloys, amalgam,silver• Group II. Gutta percha, zinc oxyphosphate or

other base materials, composite with opacifier, rubber base impression material, calcium hydroxide with opacifier

Group III. Porcelain Group IV. Radiolucent. Calcium hydroxide,

composite, resin

Gold crowns, amalgams

Retention pins

porcelain crowns

crownamalgam

crown

silver pointsgutta percha

cast post

Red arrows point to basesGreen arrow indicates recurrent caries with fractured restoration

Compositesold new

Clinic

Procedures

When you report to the Radiology Clinic, take the signed chart to the reception desk. The desk person (usually Kisha, seen at left) will dispense the necessary films, a film bag and paralleling periapical instruments.

After being assigned to a cubicle by an instructor, check to make sure it has been properly prepared. This will usually be taken care of before you get to the cubicle. If not, trays with the necessary barrier materials are available.

tubehead cover

headrest cover exposure switch cover

rubber bandpaper towel

Cubicle Preparation

Cover the appropriate equipment as indicated by the labels above. The rubber band is used to tighten the plastic around the PID on the tubehead. The paper towel is used to dry films as you take them.

Seat the patient. Adjust the headrest so that it supports the head properly. Raise or lower the chair as needed.

If you have not reviewed the patient’s medical and dental history, identify the following:

1. Is the patient pregnant

2. Does the patient have any symptomatic teeth

3. Have dental x-ray films been taken recently.

Films will normally have been ordered before coming to the Radiology Clinic. After seating the patient, if you have not already done so, check the patient’s mouth before starting to take films. A patient may have missing teeth (spaces open or closed), very small teeth, etc., and you may be able to eliminate some of the films. Consult with the instructor.

BEFORE PATIENT

1

2

3

PAPERWORK

PAPER FILM BAG

FILM & RINNS

PLACE ON LOWER COUNTER

OPEN & PLACE ON TOP COUNTER BEHIND TRAY

EMPTY FILMS FROM PLASTIC BAG ONTO TRAY; EMPTY RINN

INSTRUMENTS (BW &/OR PA) FROM POUCH ONTO TRAY

SEAT PATIENT

4

5

6

LEAD APRON

HEAD REST

HAND GEL/GLOVES

PLACE WITHOUT GLOVES

ADJUST TO SUPPORT HEAD

CLEAN HANDS AND PUT ON GLOVES

7

8

9

10

WITH GLOVES ON...

RINNS

FILMS

UNWRAPPED AREAS

CLINASEPT

ASSEMBLE INSTRUMENTS (SEE PICTURES AT LEFT)

DOT-IN-SLOT AND WHITE SIDE FACING RING (SEE PICTURES)

DO NOT TOUCH (SEE # 18)

TEAR OPEN CLINASEPT BARRIER AND DROP FILM INTO BAG

WITHOUT TOUCHING EITHER FILM OR BAG

AFTER LAST FILM PATIENT SEATED WITH APRON ON; GLOVES STILL ON

11

12

13

14

15

16

17

BARRIERS

RINNS

PAPER TOWEL &

COTTON ROLLS

GLOVES

HAND GEL

LEAD APRON

DISMISS PATIENT

REMOVE; DISCARD PLASTIC BAGS AND RUBBER BAND

TAKE APART; LEAVE ON TRAY

DISCARD

REMOVE AND DISCARD

CLEAN HANDS

REMOVE (WITHOUT GLOVES)

SEAT IN RECEPTION AREA; HAVE PATIENT REMOVE

EARRINGS, NECKLACE, ETC., IF PAN NEEDED

CUBICLE CLEANUP

18

19

20

21

22

DISINFECT

CUBICLE

TRAY & RINNS

GRADE SHEET

PAPER FILM BAG

DISINFECT AREAS TOUCHED WITHOUT BARRIERS

INSPECT FOR TRASH ON FLOOR, ETC.

TO CUBICLE F; RINNS IN SINK, TRAY ON LOWER COUNTER

PLACE BY VIEWBOXES IN BACK ROOM

TAKE FILM BAG TO DARKROOM

Place the instrument(s) and films on the tray. You can dump the films and instruments out of their bags onto the tray, but don’t touch them. Set up the film bag off of the tray so that it is ready to receive the films as you take them.

The next step is to place the lead apron/thyroid collar on the patient. The velcro pad (green arrow) should face you as you place the apron on the patient. Secure the apron by taking the strap behind the patient’s neck and securing it to the pad. Then position the thyroid collar (yellow arrow) using the velcro attachments.

Wash your hands and put on gloves. We use vinyl gloves, with extra small, small, medium, large and extra large sizes available. Gloves must be worn when handling films or assembling instruments.

The “instant hand antiseptic” seen at right may be used in place of washing the hands, assuming your hands are not visibly soiled. This is available in each cubicle.

You are now ready to assemble the instruments and take the films on the patient. Always start with the more anterior films. If you are doing a full series, start with the anterior periapicals, then do the posterior periapicals (premolar then molar in each quadrant) and finish with the bitewing films. When taking bitewings, always do the premolar film before doing the molar film. (Review technique lectures so that you will be prepared).

Criteria for Radiographic Exposure:

Only those films considered necessary for a proper diagnosis will be ordered.

Recent films (within six months) taken by an outside dentist should be requested for evaluation prior to ordering new films. Potential inferior quality of duplicates should be mentioned to patient.

The pregnant patient should be exposed to x-rays only for the information that is diagnostically required for planned treatment during pregnancy.

Criteria for Radiographic Exposure:

The lead apron and thyroid collar will be used on all patients for intraoral films. The lead apron only (no thyroid collar) is used for panoramic films.

The operator must stand behind the barrier provided for each cubicle. The operator must observe the patient through the leaded glass window during the exposure of each film.

• Universal precautions: Protect patient and operator from cross- contamination

• Cover x-ray tubehead, exposure switch and headrest with plastic

• Place lead apron (no gloves)

• Empty instruments/films onto tray

• Clean hands before gloving

Infection Control

• Do not touch anything but films, instrument, patient, and covered x-ray equipment with gloves on

• Don’t wear gloves outside cubicle

• Dry film packet, remove film from Clinasept. DON’T TOUCH FILM

Infection Control

• After completing films, remove plastic and disassemble instruments

• Remove gloves and clean hands with alcohol gel or soap/water

• Remove apron

• Disinfect if needed (Wipe those areas that were touched and not covered with plastic)

Infection Control

Panoramic machine:

• Use gloves when placing and removing bitestick cover

• Wipe down bitestick, chin rest, forehead positioner and lateral head positioners with Birex

Infection Control

Object Localization

Radiographic Definition Closer to film = sharper

Right-Angle Technique (Occlusal) Buccolingual location

Buccal Object Rule (SLOB) Two films; different horizontal or vertical angulations

Radiographic definition

Right Angle (Occlusal) technique

Two films are needed. There must be a change in the horizontal or vertical angulation of the x-ray beam to get movement of the image of the object on the film.

Buccal Object Rule

Same Lingual Opposite Buccal(Compares object movement with tubehead movement)

When using the SLOB rule, the direction of the beam must be opposite to the way the tubehead is moved.

Horizontal Tube Shift: When the tubehead is moved mesially, the beam must be directed more distally (from the mesial). If the tubehead is moved distally, the direction of the beam must be more towards the mesial (from the distal).

Vertical Tube Shift: The SLOB rule also works for movement of the tubehead in a vertical direction. When the tubehead is raised, the beam is directed down and when the tubehead is lowered, the beam is directed upward.

Buccal Object Rule

Same Lingual Opposite Buccal(requires two films)

incisors

canine

premolar

molar

Horizontal movement of the x-ray beam

Maxillary PA

BW

Mandibular PA

Vertical movement of the x-ray beam

tubehead

canine premolar

restoration

Tubehead movement

premolar molar

Lingual object

Buccal object

molar premolar

tubehead

canine

tubehead

premolarcanineincisor

tubehead

tub

ehead

BW

PA

X-ray machine

Sensor

Computer

Monitor

Printer

Digital Radiography

X-ray Machine

Low kVp (70), mA (5)

Accurate timer

Small focal spot

DC circuit

Underexposure Graininess

Sensors CCD: Charged Coupled Device CMOS: Complimentary Metal Oxide Semiconductor

Real Time Imaging (Direct)

Wired (most common) or wireless

Image Receptors

Pros “Instant” image Better resolution More durable Cons Rigid and thick (3 to 8 mm) Expensive ($5,000 to $14,000) Most have wire connecting sensor to computer

to computer

CCD, CMOS

Plates PSP: Photo-stimulable Phosphor Laser scan (Indirect)

Requires reduced lighting when scanning sensor plates

Images erased by exposure to light before reusing plate

Image Receptors

Sensor Plastic sleeve

PSP: Photostimulable Phosphor

Pros Patient friendly; no change in technique More film sizes to choose from Plates relatively inexpensive ($35+) Wider exposure latitude

Cons Easily damaged More time consuming (laser scan) Less resolution

Use paralleling, bisecting angle or bitewing technique. Biteblocks are different for the direct sensors, but rest of instrument is the same.

Biteblocks for CCD, CMOS

Regular Rinn instruments for PSP

Both Direct and Indirect digital systems have panoramic and cephalometric applications. The direct is much more expensive.

Computer

2+ GHz Pentium 4 with 256 MB RAM

Large storage capacity hard drive Periapical = 300-400 KB Pan/ceph = 4-7 MB

CD/DVD writer

Laptop optional

Monitor

CRT for radiographic interpretation

LCD flat panel for patient presentation

Best for color, such as photos

Contrast ratio of 400:1

Dpi less than 0.27 mm

Printer

Diagnosis made on monitor

Good quality ink jet or dye sublimation

Photo quality paper

Digital Radiography Advantages

• Reduced patient exposure (60-90%)

• Ability to enhance image

• Improved patient education

• “Instant” image (CCD, CMOS)

• Better workflow (CCD, CMOS)

Digital Radiography Advantages

• Environmentally friendly (no lead, silver)

• No darkroom errors

• Improved archival quality of images

• Easier transfer of information

(continued)

Cost comparison

New practice: digital cheaper

Ongoing costs: digital cheaper

CCD/CMOS system cheaper than PSP when buying only one sensor

Check warranty costs

Practice Management Software

Most systems compatible but check to make sure DICOM compliant digital software; better digital image management and sharing of information

Application Service Provider

Store images on Internet site

Small monthly service fee

“Chat” rooms (password protected)

Scanners

Archive current films

Manipulate digital image of films to “recover” information

Send information to insurance carrier

Case presentations

Probably not worth time/cost

caries perio localization

Documents