Identifying Diseases of the Teeth and
Oral Cavity Through Radiographic Images
Allan G. Farman, BDS, EdS., MBA, PhD;
Sandra A. Kolsom, CDA-Emeritus, RDA;
ADAA 2013 Council on Education
Continuing Education Units: 4 hours
Online Course: www.dentalcare.com/en-US/dental-education/continuing-education/ce433/ce433.aspx
Disclaimer: Participants must always be aware of the hazards of using limited knowledge in integrating new techniques or
procedures into their practice. Only sound evidence-based dentistry should be used in patient therapy.
This course will help the dental professional to understand the importance of high-quality radiographic
images and will, in the long run, make him or her that much more valuable to the dental team.
Conflict of Interest Disclosure Statement
• The authors report no conflicts of interest associated with this work.
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Overview
By law and by practice, the dentist is responsible for diagnosing conditions of the teeth and jaws.
Nevertheless, the whole team of dental professionals should have knowledge of how basic dental diseases
appear on radiographic images. This knowledge will help the auxiliary to understand the importance of highquality, diagnostic radiographic images and will, in the long run, make him or her that much more valuable to
the dental team.
Learning Objectives
Upon completion of this course, the dental professional should be able to:
• Recognize the radiographic appearance of dental caries, periodontal disease, periapical pathology, and
healing of extraction wounds.
• Have a basic knowledge of the radiographic appearance of tooth and bone fractures, developmental
anomalies and regressive changes of the teeth, and developmental abnormalities of the skull and jaws.
Course Contents
•Glossary
• Defective Restorations and Dental Caries
Defective Restorations
Enamel Caries
Dentin Caries
Recurrent Caries
Cervical Burnout and Mach Banding
• Periodontal Disease
Dental Calculus
Proliferative Gingival Hyperplasia
Horizontal Bone Loss
Vertical Bone Loss
• Periapical Pathology
Acute Apical Periodontitis
Acute Periapical Abscess
Chronic Periapical Abscess
Periapical Granuloma
Apical Radicular Cyst
Osteosclerosis and Condensing Osteitis
Osteoradionecrosis and Osteonecrosis
• Healing of Extraction Wounds
Normal Healing
Fibrous Healing
Socket Sclerosis
Residual Root Fragments
•Fractures
Fractured Teeth
Fractured Bones
• Developmental Abnormalities
Supernumerary Teeth
Hypodontia
Macrodontia
Microdontia
Hutchinson’s Teeth
Evagination
Invagination (Dens in Dente)
Taurodontism Pyramidal Teeth
Dilaceration
Supernumerary Roots
Fusion and Gemination
Concrescence
Regional Odontodysplasia
Dentinogenesis Imperfecta and Dentin
Dysplasia
Amelogenesis Imperfecta
Turner’s Tooth and Environmental Hypoplasia
Talon Cusp and Enamel Pearl
• Regressive Changes of Teeth
Attrition
Abrasion
Erosion
Pulp Stones
Hypercementosis
Ankylosis
External Resorption
Internal Root Resorption
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• Developmental Anomalies of the Skull and Jaws
Mandibular Tori
Maxillary Torus
Stafne Bone Cavity
Clefts
•Conclusion
• Course Test Preview
• References
• About the Authors
blood and lymph vessels, typically as a result of
inflammation.
Glossary
granuloma – A tumor that is filled with granulation
tissue.
fibrous – Composed of or containing fibers.
furcation – The point at which the roots of multirooted teeth separate.
gonadal – Pertaining to the ovaries or testes.
abrasion – Pathological wearing away of the
surface layers of hard or soft tissues.
hemihypertrophy – An excessive growth of one
half of the body, an organ, or a part (e.g., facial
hemihypertrophy).
anomaly – abnormality
apical foramen – An opening at a tooth’s root tip
that allows the entry of nerve and blood vessels to
the pulp.
incipient – The beginning stage; e.g., incipient
caries is the beginning stage of tooth decay when
the decay has not yet completely penetrated the
enamel.
attrition – Wearing away by friction or rubbing.
autosoma – Pertaining to a chromosome other
than a sex chromosome.
intraosseous – Within bone.
lamina dura – The compact bone that lines the
tooth sockets.
bilateral – Two sided.
cementoenamel junction – The meeting of the
enamel of the crown and the cementum of the root
at the cervix of a tooth.
lobulated – Divided into lobes, subdivisions.
chronic – Persisting over a long period of time.
opalescent – A translucent appearance.
dysplasia – Abnormal growth or development of
cells, tissue, bone, or an organ.
orifice – The entrance or outlet of any body cavity.
necrosis – The death of cells or tissues.
osseous – Bony or of bone-like structure or
consistency.
ectopic – Out of place; e.g., an ectopic tooth
eruption is one that occurs outside the normal path.
ossification – The formation of bone or a change
into bone.
embrasure – The V-shaped space between
curved adjacent surfaces of teeth.
pathosis – A disease condition.
epithelial – Type of tissue that forms the covering
of all body surfaces.
periodontium – A collective term that denotes
the tissues surrounding and supporting the teeth;
includes 1) the gingiva, 2) the cementum of the
tooth root, 3) the periodontal ligament, and 4) the
alveolar bone.
erosion – The destruction of tooth substance by
chemical or mechanical-chemical action.
exfoliate – To shed teeth, particularly referring to
primary teeth.
polyp – A general term that describes any mass
of tissue that bulges or projects outward or upward
from the normal surface level.
exudate – A liquid substance that oozes from
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prognathic – Pertaining to a forward relationship
of the jaws to the head (anterior to the skull)
resulting in a protruding lower face.
radiodensity – The degree of radiolucency or
radiopacity of a substance or tissue.
radiolucent – A term that describes the ability of a
substance or tissue to allow passage of radiation
with relatively little attenuation (reduction of
energy) resulting in a darker image on a finished
radiographic image.
radiopaque – A term that describes the ability
of a substance or tissue to attenuate (reduce or
slow) the energy of radiation that passes through it
resulting in a lighter image on a radiographic image.
Figure 1. Defective Restoration on #4
Enamel Caries
While advanced dental caries may well involve the
entire tooth, early or incipient caries involves only
the enamel. Once a carious lesion penetrates
through the enamel, it is usually considered to be
dentinal caries. Clinically, enamel caries usually
appears as a stained system of occlusal grooves
or as chalky white bands along the labial/buccal
gingival aspects of the teeth. Radiographically,
enamel caries is characterized by a focal loss of
the normal enamel radiopacity, particularly on the
interproximal surfaces.
sclerosis – Hardening of a body tissue.
scurvy – A condition that results from an
ascorbic acid (vitamin C) deficiency; common
symptoms include weakness, poor wound healing,
and hemorrhage under the skin and mucous
membranes.
suppurative – Forming pus.
taurodontism – An anatomical abnormality
in which a tooth’s pulp chamber is elongated,
enlarged, and extends into the region of the roots.
It appears as a radiolucent cone shape, with the
base at the exterior surface and the tip of the cone
toward the pulp. The lesion follows the enamel
rods. After progression into the dentin the lesion
usually takes on a radiolucent fan shape.
Defective Restorations and Dental Caries
Defective Restorations
The junction of a restored tooth and the restorative
material should always appear sharp and distinct,
though there will be some qualitative differences
for interposed radiolucent bases. Restorations that
radiographically fail to extend to tooth preparation
margins (open margins), those that extend beyond
the preparation margins (overhangs), and those
with inappropriate contours may be considered
defective restorations. Such restorations are
usually defective at the time they are inserted,
though they may become defective as a result of
fracture, attrition, abrasion or erosion.
To locate interproximal caries, an interproximal
or bitewing survey is usually most valuable
because the maxillary and mandibular teeth
are simultaneously imaged on one image and
the projection geometry is most favorable for
accurate imaging. Anterior bitewing examination
requires a change of geometry, which is not
as favorable for interproximal caries detection.
These interproximal surfaces are thin and can be
easily examined clinically. Periapical examination
of the anterior region is useful for the detection of
cemental caries.
Figure 1 is a molar bitewing radiographic image
that discloses a defective abutment restoration on
tooth #4. The restoration ends short leaving open
margins.
To be detectable on a radiographic image there
must be a 30% to 50% change in the mineral
content of the enamel lesion. Less than 30%
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Figure 3. Dentin Caries
of existing restorations. A diligent search for
recurrent caries should be made whenever
radiographic images detect:
1. interproximal restoration overhangs;
2. open margins on restorations;
3. restorations which appear to end short of
preparation margins;
4. restorations which appear unusually shallow
as judged by the thickness of the restorative
material.
Figure 2. Advanced Enamel Caries
demineralization will not produce a detectable
image. The advancing edge of the lesion may
not be 30% demineralized and thus will appear
smaller in the radiographic image because the
rest of the advancing edge is not radiographically
visible. Clinically the lesion will usually be larger
than its radiographic image.
Radiographically, recurrent caries presents
as radiolucent lines that extend inward from
the tooth surface along a restoration or as
radiolucent zones, which appear to lie completely
beneath the restoration, without any observable
communication with the tooth surface. As
mentioned previously, the junction of a restored
tooth and the restorative material should appear
sharp and distinct, and, as a rule, recurrent caries
should be suspected whenever radiolucencies are
present between the tooth and the restoration.
Figure 2 illustrates fairly advanced enamel caries.
Dentin Caries
Dentin Caries extends into the tooth dentin
and can be recognized by noting the focal loss
of dentinal radiopacity. Most commonly, this
darkened dentin is located beneath carious
enamel and, typically, the lateral dimension of
the dentinal involvement exceeds that of the
associated enamel caries (Figure 3). Dentin caries
may be discerned interproximally, on the occlusal
surface, buccally/lingually, or on root surfaces.
In Figure 4, recurrent caries appears at the mesial
of tooth #3 and #4, and the distal of tooth #28.
Also, note areas of interproximal caries on tooth
#5 and #6.
Cervical Burnout and Mach Banding
Cervical burnout is an area of apparently
increased radiolucency in the mesial and distal
cervical (neck) regions of the tooth. Such regions
are often mistaken for interproximal caries when
in fact they only appear radiolucent because they
have neither the radiopaque enamel of the region
Incipient occlusal dentin caries may be difficult to
identify on radiographic images and root caries
must be carefully distinguished from cervical
burnout, as we will discuss later.
Recurrent Caries
Recurrent Caries is the condition in which carious
lesions develop or extend along the margins
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so sharply defined.
Occlusal caries may be undetectable on a
radiographic image until the decay reaches the
dentin. Early radiographic appearance may be
a thin radiolucent shadow below the enamel.
An optical illusion referred to as Mach banding
can produce the same image in healthy teeth.
Detection of incipient occlusal caries is most
effective by direct clinical examination.
Periodontal Disease
A tooth in the intact periodontium maintains firm
attachment to a collar of the gingiva through
connective tissue fibers. Beneath the gingiva,
bone is attached to the root surface through the
periodontal ligament, a complex system of fibrous
connective tissue. Deposits of free bacteria and
bacteria-rich plaque produce inflammation in the
gingival collar, which, in turn, disrupts the fibrous
gingival-tooth attachment.
Figure 4. Recurrent Caries
The continued presence of plaque and calculus
produces inflammation in the periodontal ligament,
leading to bone loss and weakened attachment
strength between the ligament and the tooth.
In time, the inflammatory process can cause
considerable bone loss – to the point that the tooth
becomes unstable and eventually is lost.
Figure 5. Cervical Burnout
Ongoing research is pointing towards collaboration
between certain systemic diseases and periodontal
health. As dental professionals it is our responsibility
to discuss these findings with our patients.
immediately above nor the bone tissue below.
Figure 5 illustrates cervical burnout in a premolar
bitewing radiographic image. Note that the
cementoenamel junction and the crest of the
alveolar bone lie respectively just above and just
below the burnout area. As a point of comparison,
note the interproximal enamel caries on the first
and second premolars.
Clinically, the extensive bone loss and gingival
recession of advanced periodontal disease may
be easily visualized. In less advanced cases,
the periodontal probe can be used to measure
the distance between the gingival crest and the
periodontal attachment. Bleeding at the point of
probing and measurement of significant distances
are strong indications of periodontal disease.
Figure 6 radiographically illustrates probe depth in
a case of moderate periodontal disease with early
alveolar bone loss. Figure 7 illustrates severe
periodontal disease with extensive loss of alveolar
bone around the tooth.
While carious lesions and areas of cervical
burnout do resemble each other, there are a
couple of tips to help differentiate between them.
First, cervical burnout is found only in the cervical
region or tooth neck, which is fortunately an
uncommon area for caries to develop. Second,
the cementoenamel junctions sharply limit areas
of burnout incisally and occlusally, as the alveolar
crest limits the area apically. Caries would not be
Dental Calculus
Dental Calculus is mineralized dental plaque.
Heavy calculus deposits are most commonly found
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Figure 8. Calculus on Distal of Maxillary Molar
Figure 6. Probe Depth in Moderate
Periodontal Disease
Figure 9. Gingival Hyperplasia
of the maxillary molar in Figure 8.
At times, calculus deposits become so heavy
that they completely surround the tooth. Not
surprisingly, such severe cases are associated
with advance periodontal bone loss.
Figure 7. Extensive Loss of Alveolar Bone
opposite the salivary duct orifices located near
the mandibular incisors and maxillary molars.
Calculus is usually classified as supragingival,
which occurs above the gingiva on the exposed
tooth surfaces and subgingival, which is found
beneath the gingiva. It is well known that the
bacteria on the calculus induces inflammation
in the periodontal tissue and contributes to the
development of gingivitis and periodontal disease.
Proliferative Gingival Hyperplasia
Gingival enlargements arise from a variety of
local and systemic factors, and may be localized
(Figure 9) or may involve the entire gingival area.
Localized gingival enlargements most commonly
result when a discrete area of the gingiva is
irritated by plaque, calculus or extrinsic factors
such as popcorn hulls or hard candy. Less
frequently, local conditions represent an extension
of underlying bone disease.
On a dental radiographic image, calculus is
commonly seen interproximally, either filling
the dental embrasures or producing distinct
radiopaque spurs such as that seen on the distal
Generalized gingival enlargement may result from
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longstanding, chronic inflammation such as that
noted in chronic gingivitis or periodontitis. It has
also been associated with the hormonal changes
that occur with puberty and pregnancy, with
certain drug therapy (i.e., Cyclosporins, Dilantin,
Nifedipine), with systemic disorders such as
scurvy and leukemia, and with genetic disorders
such as fibromatosis gingiva.
representing the residual bone crest sharply
intersects another line between the tooth necks.
Vertical loss is sharply apparent distal to the
maxillary first molar and between the premolars
(Figure 11).
Vertical bone loss may extend to the root apex,
and prominent calculus deposits are often noted.
Care must be taken to assess the degree of bone
loss, especially around molars where special
attention should be directed to the furcational
periodontal ligament space.
In nearly all cases, generalized gingival
enlargements produce only minimal osseous
change; and, thus, if they are definable on
radiographic images at all, it is only on the basis
of their increased gingival soft tissue outline.
Vertical bone loss extending into this area may
appear as a focally widened ligament space.
Horizontal Bone Loss
Generalized, extensive periodontal bone loss, in
which the crest of the residual bone is parallel
to the cementoenamel junction, is referred to as
horizontal bone loss (Figure 10).
Periapical Pathology
Acute Apical Periodontitis
Following the necrosis of the dental pulp through
any cause, irritants drain and can cause a reaction
in the periodontal tissues adjacent to the apical
foramen. There is usually little, if any, immediate
bone resorption, therefore apical periodontitis is
often difficult to detect with radiographic images
except that the tooth may appear slightly elevated
in the tooth socket due to the collection of
inflammatory exudate.
Vertical Bone Loss
With periodontal disease, bone loss may be
relatively severe around some teeth, while leaving
the immediately adjacent teeth firmly anchored.
Such focal loss creates osseous defects
whose height varies markedly compared to the
adjacent tooth crowns. This defect is known
as vertical bone loss and can be recognized
on a radiographic image by noting that a line
Acute Periapical Abscess
Acute, by definition, means short term. Acute
abscesses often show little radiographic change
because over the short run, the body has not had
sufficient time to resorb bone.
Figure 11. Vertical Bone Loss
Figure 10. Horizontal Bone Loss
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Chronic Periapical Abscess
The chronic periapical abscess represents a
suppurative process that has been present long
enough to cause the body to resorb bone. It is
not possible to absolutely differentiate between
a chronic abscess, dental granuloma, or small
radicular cyst solely by using a dental radiographic
image. However, a radiographic image of multiple
foraminae (many openings or passages) within
the pathological area is strongly suggestive of
sinus tract formation and drainage of pus. Notice
the four prominently radiolucent foraminae in the
resorbed periapical area (Figure 12).
Apical Radicular Cyst
Epithelial remnants from tooth formation are
always present as builder’s debris within
the periodontium. These remnants can
proliferate within an apical granuloma to form
an apical radicular cyst, which can grow to
several centimeters if left untreated. Apical
radiolucencies greater than about six millimeters
usually contain epithelial cyst material. Figure 14
illustrates a clearly defined apical periodontal cyst
in a pulpless tooth following acute trauma.
If the process starts from a lateral, rather than an
apical canal, a lateral radicular cyst can occur.
Notice how the cystic formation in Figure 15
follows the lateral aspect of the tooth root, thus
differentiating it from an apical cyst.
Periapical Granuloma
The periapical granuloma represents the body’s
defense mechanism attempting to wall off irritants
draining from a non-vital dental pulp. While
they cannot be radiologically differentiated from
abscesses or cysts, they can be differentiated
from normal anatomical landmarks such as the
incisive fossa because the periodontal ligament
space is widened and the lamina dura is not
continuously intact.
A cyst can continue to grow even after the
irritation has ceased or the source has been
removed. Such continuing growths are termed
residual cysts.
Osteosclerosis and Condensing Osteitis
Increased bone deposition may be secondary to
a variety of local irritants, most notable infection.
Such increased bone deposits are termed
osteosclerosis, or alternatively, condensing
osteitis. Figure 16 illustrates the radiographic
appearance of condensing osteitis surrounding
Figure 13 illustrates apical periodontal pathosis in
the area of the right central incisor. Note the loss
of continuity of the lamina dura and the widened
periodontal ligament space on the affected side.
Figure 12. Radiolucent Foraminae
Figure 13. Apical Periodontal Pathosis
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Figure 16. Condensing Osteitis
or sclerosing osteitis.)
Osteoradionecrosis and Osteonecrosis
Osteoradionecrosis (ORN) also known as
postradiation osteonecrosis (PRON), is a serious,
debilitating and deforming potential complication
of radiation therapy for the treatment of cancer.
It is known to occur following radiation treatment
when the maxilla or mandible is directly in the
field of radiation.
Figure 14. Apical Periodontal Cyst
Bisphosphonate-associated osteonecrosis of the
jaw (ONJ) is uncommon but has been associated
with intravenous bisphosphonate cancer therapy.
Any necessary dental procedures should be
completed before intravenous bisphosphonate
cancer treatment is started. More research is
needed for patients receiving oral bisphosphonate
for the treatment of osteoporosis. At this time, it
does not seem to be a serious risk and normal
dental services are recommended.
Diagnosis depends primarily on clinical and
radiographic changes in the bone. These signs
and symptoms typically include ulceration of the
mucosa, loosening of the teeth and exposure of
necrotic bone.
Figure 15. Lateral Radicular Cyst
the apices of a deeply carious first molar.
Healing of Extraction Wounds
Although osteosclerosis is commonly associated
with carious, frequently non-vital teeth, it may also
be found at the apices of entirely normal teeth,
most commonly the mandibular first permanent
molar. It should be pointed out that involved
teeth usually show fully formed roots without a
significant degree of root resorption. (Other terms
used to indicate condensing osteitis are rarefying
Normal Healing
Following normal tooth extraction, the extraction
socket is clearly demarcated by the radiopaque
bundle bone into which the periodontal ligaments
had anchored the tooth. A radiographic image of
a recent first mandibular molar extraction site is
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Figure 17. Recent Extraction Site
Figure 18. Fibrous Tissue Healing
illustrated (Figure 17). Note the clear outline of
the root socket.
With healing, new bone is deposited into the
socket, and, with time, the bundle bone slowly
fades. After about 18 months, it can no longer be
distinguished from the surrounding tissue.
Fibrous Healing
Occasionally dental extraction sites lay down a
fibrous tissue healing. Such tissues appear as
radiolucent areas such as that in Figure 18 and
sometimes last for periods well in excess of the
normal healing time.
Figure 19. Socket Sclerosis
Socket Sclerosis
If healing is accompanied by excessive bone
deposition, socket sclerosis results, leading to
radiodense areas within the socket as illustrated
(Figure 19).
Residual Root Fragments
If the tooth is not completely removed, e.g.,
because of a root fracture or residual deciduous
tooth root, a residual tooth fragment may
persist. These fragments can be distinguished
from socket sclerosis by the presence of a root
canal and an intact periodontal ligament space.
Figure 20 illustrates the appearance of a residual
root and intact ligament space following the
extraction of a mandibular first molar.
Figure 20. Residual Tooth Fragment
Fractures
Fractured Teeth
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Figure 22. Fractured Root
Figure 21. Fractured Incisal Edges
Traumatic injuries, extensive caries and oral
neglect can lead to fracturing of the dental
tissues. Maxillary incisors are particularly prone
to traumatic injuries. The fracture often leads to
losing portions of the tooth crown such as the
traumatic loss of the incisal edges (Figure 21).
A crown fracture can also affect the tooth root,
appearing as a radiolucent line across or with
the tooth’s long axis. Be careful not to mistake
the artifact of a fingernail crimp as a fracture!
Figure 22 is a radiographic image of a fractured
tooth. A fingernail crimp would be very similar,
though possibly somewhat more broad and
radiolucent (Figure 23).
Fractured Bones
Even though bone is usually strong and resilient,
a forceful blow can cause it to break. Therefore,
patients with a history of traumatic injury and a
clinical picture of bruising and tenderness should
be radiographed to detect a fracture. Depending
on the nature of the injury, a fracture can be
a straight or jagged line, which may penetrate
partially or completely through the bone and
leave the bones normally aligned or displaced.
Figure 24 illustrates a non-displaced mandibular
fracture in the canine region.
Figure 23. Fingernail Crimp on
Radiographic Image
During healing, the body often lays down excess
bone or callus in the injured area. This callus
and retained intraosseous wiring is visible at the
healed fracture site (Figure 25).
Developmental Abnormalities
If the fracture site is unstable, or displaced,
intraosseous wiring is used to maintain position
during healing.
Supernumerary Teeth
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Figure 24. Non-displaced Mandibular
Fracture
Figure 25. Callus at Healed Fracture Site
The relatively common abnormality of teeth
numbering in excess of the standard 32
permanent or 20 deciduous is known as
supernumerary dentition. Areas of the jaws most
frequently affected with supernumeraries include
the maxillary central and lateral incisor and molar
regions, and the mandibular premolar region.
The most common supernumerary tooth is the
mesiodens, occurring between the maxillary
central incisors (Figures 26 & 27). This tooth is
usually small and cone-shaped and may be either
erupted or impacted.
Supernumerary teeth of the maxillary molar region
occur either distal to the third molar, thus called
fourth molars, or between or adjacent to the third
and second molars, becoming paramolars.
Figure 26. Mesioden
Multiple-impacted supernumerary teeth are
classically associated with Gardner’s Syndrome,
a hereditary condition marked by multiple polyps
of the colon, and cleidocranial dysplasia, a rare
hereditary condition in which there is defective
ossification of the cranial bones and complete
or partial absence of the clavicles. Given the
serious ramifications of these diseases, it is vitally
important to consider them whenever multiple
supernumerary teeth are encountered.
Figure 27. Mesioden
Hypodontia
Missing teeth is an exceedingly common finding,
which can usually be attributed to extraction or
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traumatic evulsion. Such acquired hypodontia
must be contrasted with congenital hypodontia,
which arises because of a developmental error.
Congenital hypodontia most commonly affects
the third molars, the permanent maxillary lateral
incisors and the maxillary and mandibular
premolars. Frequently, hypodontia is bilateral.
Figure 28 is an example of a patient with
congenital hypodontia, affecting the mandibular
second premolars bilaterally, the left mandibular
first permanent molar, and retention and ankylosis
of the mandibular second deciduous molars.
Figure 28. Congenital Hypodontia
More severe forms of congenital hypodontia are
associated with hereditary anhidrotic ectodermal
dysplasia, a disease characterized by the absence
of eyebrows and eye lashes; a depressed nasal
bridge; prominent supraorbital ridges; light,
scanty hair; and wrinkled palms, secondary
to hyperkeratosis. In such patients, it is not
uncommon for only three or four teeth to develop.
Macrodontia
Macrodontia is the formation of unusually large
teeth. Most commonly, this developmental
anomaly presents as a single enlarged tooth, and,
less frequently, as multiple macrodonts. Figure
29 is a right maxillary lateral incisor macrodont
with a small hypoelastic enamel defect on the
labial tooth surface.
Figure 29. Maxillary Right Lateral Incisor Macrodont
The patient’s radiographic image, shown in Figure
30 clearly outlines the macrodont and additionally
reveals an impacted maxillary canine.
As noted earlier, macrodontia usually results
in a single large tooth. Much less frequently,
multiple macrodonts are encountered with such
conditions as facial hemihypertrophy and pituitary
giantism. Tooth fusion, which will be discussed
later, produces teeth that are virtually identical
to macrodonts; and, indeed, it may well be
impossible to distinguish between the two.
Microdontia
Microdontia is a condition characterized by
unusually small teeth. Again, it commonly affects
only one tooth, most often the maxillary lateral
incisor or peg lateral and the third molar. It may
also manifest as a feature of other anomalies
such as supernumerary teeth. Figure 31 is a
Figure 30. Macrodont and Impacted
Canine
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maxillary third molar microdont.
Generalized microdontia is very uncommon. It
has been associated with pituitary dwarfism,
hypoplastic type amelogenesis imperfecta and
anhidrotic ectodermal dysplasia.
Hutchinson’s Teeth
Hutchinson’s teeth result from a highly distinctive
form of enamel hypoplasia, occurring only in
congenital syphilis. Affected incisors demonstrate
convergence of mesial-distal dimension
approaching the incisal edge. Typically, there
is a distinctive notch on the mid-incisal edge,
which has been likened to the appearance of
a screwdriver (Figure 32). All maxillary and
mandibular incisors may show the defect,
although the maxillary lateral incisor may appear
normal while the others are defective.
Figure 31. Maxillary Third Molar Microdont
Evagination
Evagination represents a somewhat rare dental
developmental malformation in which there appears
to be a small accessory cusp arising from the
occlusal surface of a tooth. Figure 33 illustrates a
maxillary premolar with evagination occupying the
space between the buccal and lingual cusps.
Although it may occur on any tooth, it is most
commonly observed on the premolars. The
malformation is composed of enamel and dentin
and may extend into the pulp; and thus, attrition
on caries involving the evagination may lead to
pulp necrosis and periapical disease.
Figure 32. Hutchinson’s Teeth
Invagination (Dens in Dente)
Invagination represents a deep infolding of the
tooth with extension of the enamel down through
the dentin into the pulp. Such teeth can be
severely deformed, appearing with an enlarged
pulp chamber that has been likened to a tooth
within a tooth (dens in dente).
The most commonly affected tooth is the
permanent maxillary lateral incisor (Figures 34 &
35). Single dens in dente are most common, but
double varieties also occur.
Taurodontism Pyramidal Teeth
Taurodontism is a fairly common developmental
defect in which the affected multi-rooted teeth
Figure 33. Maxillary Premolar with
Evagination
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display apically displaced furcation, producing a
pattern of large pulp chambers and short roots.
Clinically, the teeth appear normal, but on a
radiographic image, they demonstrate a distinct
rectangular outline, such as seen in tooth #19
(Figure 36).
Taurodontism may affect multiple teeth, but
it is limited almost entirely to the molars. It
is associated with Kleinfelter’s Syndrome, a
syndrome of gonadal defects, appearing in males,
with an extra X chromosome, which should be
suspected whenever taurodontism is encountered
in patients with unexplained mental retardation, a
tall, thin appearance, long legs and arms, and a
distinctly prognathic jaw.
Pyramidal teeth are morphologically similar to
taurodontism. They exhibit enlarged, elongated
pulp chambers but only single roots as illustrated
in tooth #18 (Figure 36). In effect, the condition
appears to represent extreme apical displacement of
the furcation, resulting in a single broad root, which,
in actuality, is the body of the tooth. The clinician
will sometimes encounter both taurodontism and
pyramidal teeth in the same patient.
Figure 34. Invagination
Dilaceration
Dilaceration is an unusual bend in the tooth
root(s). The curvature usually results from trauma
and can occur anywhere along the root. Since
the tooth crown is clinically normal, the degree of
dilacerations can only be detected radiographically.
Figure 35. Invagination
Dilaceration may range from mild curvature
(Figure 37) to severe bending (Figure 38).
The curvature is more visible if it occurs in a plane
perpendicular to the central X-ray beam. If it occurs
parallel to the beam, it casts a shadow similar to a
radiopaque cyst or bone deposit because the axis is
oriented toward or away from the beam.
Supernumerary Roots
Teeth having a greater number of roots than is
anatomically typical have supernumerary roots.
The canines, mandibular premolars and maxillary
second premolars are usually single rooted, and a
radiographic appearance such as that in Figure 39
would be diagnostic of supernumerary roots.
Figure 36. Pyramidal in #18; Taurodontism in #19
Fusion and Gemination
Fusion is defined as the joining of two originally
separate teeth through the dentin, or through
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Figure 38. Severe Dilaceration
Figure 37. Mild Dilaceration
the dentin and enamel. In contrast, gemination
represents incomplete division of what should
have been two separate teeth. Fusion may
involve supernumerary teeth, and gemination
may occur in quadrants also affected by partial
anodontia; thus, counting the teeth in the affected
area is of limited diagnostic value. Regardless of
which process initiated the error, it is practically
impossible to distinguish between fusion and
germination, and in either case, the tooth will
appear much like that in Figure 40.
Figure 39. Supernumerary Roots
The distinction between fusion and germination
is primarily of academic interest and thus, the
etiology is of less clinical concern than is the
presence of the condition and the potential
ramifications involved.
Concrescence
Concrescence represents the joining of adjacent
teeth via the cementum with obliteration of the
intervening periodontal ligaments. Concrescence
is usually found in two teeth, rarely in three or
more. The clinical appearance of the condition
is shown in Figure 41 and the appearance on a
radiographic image in Figure 42.
Figure 40. Fusion or Gemination
Regional Odontodysplasia
Regional odontodysplasia represents a
developmental disorder in which one or several
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teeth in a contiguous group fail to properly form.
The condition occurs sporadically without a distinct
familial pattern and most commonly affects the
anterior maxillary quadrants. The involved teeth
often fail to erupt, or if they do erupt, they are
misshapen with irregular crowns and defective
mineralization. Unerupted teeth are characterized
by soft tissue swelling and painful symptoms.
Radiographic features typically consist of one tooth,
or segment of teeth, demonstrating incomplete
formation and reduced radiopacity. Because of
their radiolucency, they are sometimes known
as ghost teeth. In Figure 43, the posterior
mandibular segment demonstrates an unerupted
and incompletely mineralized second premolar
and second molar. The first molar is absent and
swelling of the overlying soft tissue is noted.
Figure 41. Clinical Concrescene
Dentinogenesis Imperfecta and Dentin Dysplasia
Dentinogenesis Imperfecta is an inherited disorder,
usually showing a dominant autosoma pattern.
Clinically, the teeth have a peculiar translucent
appearance with discoloration ranging from
brown to yellow to gray. Such teeth are termed
opalescent.
Radiographically, all teeth in the deciduous and
permanent dentitions show early and frequently
complete obliteration of the pulp chambers and
canals with short, blunted roots (Figure 44).
Figure 42. Radiographic Concrescene
Dentin dysplasia is another autosomal dominant
condition in which there is markedly disturbed
dentin formation. This extremely rare condition
occurs in two distinct patterns. The first, referred
to as radicular dentin dysplasia, is characterized
by partial or complete obliteration of the pulp
chamber and extremely short, blunted roots
(Figure 45 & 46). When persistent, the pulp
chamber displays a characteristic crescent.
The second type is coronal dentin dysplasia and
is characterized by the thistle-funnel pulp chamber
enlargement in the permanent teeth.
Figure 43. Regional Odontodysplasia
Amelogenesis Imperfecta
Amelogenesis Imperfecta constitutes a diverse
group of distinct, genetic disorders which share
generalized defective enamel formation. As
distinct conditions, varieties of amelogenesis
imperfecta have been linked to autosomal,
X-linked, dominant, and recessive genes.
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Figure 45. Radicular Dentin Dysplasia
Figure 44. Dentinogenesis Imperfecta
Clinically, the enamel may be partially missing
(hypoelastic); very soft (hypocalcified); or
firm but chippable (hypomaturation). Varying
degrees of yellow to brown tooth discoloration
may be present. On the radiographic image,
the teeth may show hypoplasia from failure of
enamel formation or a chipped and worn-away
appearance from partial formation (Figure 47).
In cases of hypocalcification, the radiodensity of
the enamel and the dentin are very close and,
thus, delineating between them is difficult.
Figure 46. Coronal Dentin Dysplasia
Turner’s Tooth and Environmental Hypoplasia
Enamel hypoplasia, limited to a single tooth, is
known as Turner’s Hypoplasia and the affected
tooth is termed Turner’s tooth. The most
frequently affected teeth are the permanent
maxillary incisors and the maxillary and
mandibular premolars. Common causes for
the condition include local trauma or infection
derived from an overlying deciduous tooth.
Clinical appearance can range from mild, opaque
chalkiness or brown discoloration or frank enamel
pitting (Figure 48).
In contrast to the genetic nature of Turner’s
Hypoplasia, environmentally-induced
developmental failure of enamel formation
affecting multiple teeth is termed generalized
environmental enamel hypoplasia. Environmental
factors can include nutritional deficiencies,
excessive fluoride ingestion, and severe, feverproducing childhood diseases.
Figure 47. Amelogenesis Imperfecta
Clinically, the affected teeth show localized enamel
deficiency ranging from focal opacification to
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severe pitting. The distribution of enamel defects
reflects the chronology of enamel formation
with most severely affected areas representing
the area that were forming at the time of the
environmental influence.
The radiographic features of generalized
environmental enamel hypoplasia consist of
linear bands of relatively radiolucent enamel
(Figure 49). Mild opacification and focal surface
pitting may not be visible on radiographic images.
Talon Cusp and Enamel Pearl
The talon cusp represents a developmental
anomaly in which a peculiar lingual cusp forms
on the maxillary or mandibular incisors. When
small, the cusp cannot be distinguished from an
accentuated cingulum. When well-developed, the
cusp appears clinically, as illustrated in Figure 50
and, on a radiographic image, as in Figure 51.
Figure 48. Turner’s Tooth
The enamel pearl is a misplaced (ectopic)
globule of enamel, occurring most commonly in
the furcation areas or near the cementoenamel
root surfaces of the molar teeth. Affecting the
maxillary more often than the mandibular areas,
the relatively rare enamel pearls may contain a
dentin core, occasionally with pulpal extension.
Radiographically, the pearl appears as a round
or semi-spherical area of increased radiodensity.
When occurring on the mesial or distal aspects,
the pearl produces an obvious convex profile.
On the buccal or palatal/lingual aspects, it is less
easily seen and may resemble pulp stones.
Figure 49. Generalized Environmental
Enamel Hypoplasia
Regressive Changes of Teeth
Attrition
Attrition represents the physiologic wearing
away of tooth structure through such causes as
normal mastication. The incisal, occlusal and
interproximal surfaces are typically affected,
and often the enamel is worn away so that the
exposed dentin is clearly visible. Although attrition
rarely results in serious disease, advance cases
can lead to pulp necrosis and periapical disease.
Abrasion
The pathologic wearing away of tooth structure
secondary to friction is abrasion. Agents, which
contribute to abrasion include abrasive toothpaste;
improper use of a toothbrush, flosses, and
Figure 50. Clinical Talon Cusp
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Figure 52. Abrasion
Figure 51. Radiographic Talon Cusp
toothpicks; and personal habits such as excessive
brushing, and holding pins, nails, and tacks
between the teeth. A common form of abrasion
involves the cervical areas, producing a sharply
defined V-shaped defect such as that crossing the
buccal aspect of the premolar in Figure 52.
Erosion
Erosion represents loss of tooth structure caused
by chemical action. Usually these chemicals are
acidic and the process does not involve bacterial
action. Clinically, erosion is usually described in
connection with the gingival one-third of the labial
aspect of the anterior teeth, although any tooth
surface can be affected. Erosion may arise due
to environmental factors such as personal diet
and occupations that involve working with acids.
Figure 53. Erosion
Chronic vomiting may produce extensive erosion
of the lingual tooth surfaces due to the acid
nature of stomach contents (Figure 53).
Hypercementosis
Excessive deposition of cementum along the
root surface is termed hypercementosis. The
precise cause of this condition is not well
understood, although the loss of tooth antagonism
and local inflammation is often associated with
it. A special exception is osteitis deformans or
Padget’s disease, in which teeth in an affected
jaw typically demonstrate a remarkable degree of
hypercementosis.
Pulp Stones
Pulpal calcification is an extremely common finding
and is considered by many to be a variation
of normal pulpal development. Calcifications
presenting as distinct intra-chamber (or less
often intra-canal) radiopacities are known as pulp
stones. Figure 54 illustrates a prominent stone in
the pulp chamber of the second maxillary molar. It
must be noted that it is often difficult to differentiate
the radiographic appearance of a pulp stone from
the simple superimposition of furcation contours.
Radiographically, the condition is characterized
by a bulbous, opaque expansion of root contours,
usually involving much of the root length, while
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preserving the periodontal ligament space and
lamina dura (Figure 55). Less commonly, the
overgrowth is limited to the root apex.
Ankylosis
Tooth ankylosis represents a direct union of tooth
to bone, eliminating the normally interposed
periodontal ligament. Ankylosis is uncommon,
usually encountered with deciduous teeth and
often, though not exclusively, associated with local
trauma and/or infection.
Clinically, deciduous ankylosis typically presents
a retained tooth positioned below the level of the
occlusal plane and is termed a submerged tooth.
Radiographically, the ankylosed tooth typically
exhibits signs of partial root resorption, obliteration
of portions of the periodontal ligament, mild
osseous sclerosis and apparent direct attachment
of root and bone (Figure 56). On occasion,
impacted teeth will become ankylosed in the jaw.
Figure 54. Pulp Stone
External Resorption
Mild external resorption of permanent teeth is a
relatively common finding. Its specific causes can
often be attributed to trauma, orthodontic therapy,
reimplantation, cysts, tumors and infection. In
other cases, no specific cause can be identified.
Root resorption most commonly is limited to the
apical portion of the root and lacks any clinical
manifestations. However, the condition can
advance to the point that teeth become mobile
and exfoliate.
Figure 55. Hypercementosis
Radiographic appearances include blunting of
root apices with shortening of root length. In
some cases, abrupt loss may be noted, and with
advancing disease, the entire root may appear
lost. Figure 57 illustrates a marked blunting and
root loss following orthodontic therapy.
It is critically important to examine the tissues
immediately surrounding the resorbing root.
While, in most cases, the resorption is mild and
relatively inconsequential, it can be severe and
may be secondary to a number of significant
tumors, including odontogenic neoplasms and
metastatic cancer. Care must be taken to avoid
simply identifying the condition without making
a thorough investigation for signs of a far more
serious disease.
Figure 56. Deciduous Ankylosis
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Figure 57. External Resorption
Figure 58. Internal Resorption
Internal Root Resorption
Internal resorption represents a peculiar internal
dissolution of dentin, which can extend eventually
into the enamel and/or cementum by the tooth
root. Usually, only a single tooth is involved, and
although the cause is not clearly understood, it is
often linked to inflammation.
the offspring of parents with mandibular tori have a
much higher incidence of development.
Radiographically, tori appear as well-defined areas
of radiopacity overlying the tooth roots (Figure 59),
particularly extending from the canine to the molar
regions. If tori are seen on radiographic images,
they should be clinically confirmed in order to
rule out other conditions, which lead to osseous
radiopacity.
Clinically, internal resorption in the pulp
chamber may lead to the Tooth of Mummery
with a developing pink hue in the tooth crown.
Resorption in the root canal is not clinically visible;
however, perforation of the root usually requires
that the tooth be extracted.
Maxillary Torus
The maxillary torus presents as a hard, frequently
lobulated, benign overgrowth of mature lamellar
bone. It is frequently located in the midline of the
hard palate (Figure 60) and attached by a broad,
bony base.
Radiographic evidence of internal resorption
consists of an unusual widening of the pulp
chamber or canal (Figure 58). If the canal is
involved, it is virtually impossible to distinguish
between internal and external resorption.
The condition is more common in Native
Americans, American Indians and Eskimos than
in Caucasians or Blacks and has a populationwide frequency of occurrence of about 25
percent. Hereditary factors have been implicated.
Radiographically, the maxillary torus appears as
a well-defined radiopacity situated at, or superior
to, the apices of the maxillary teeth (Figure 61).
On panoramic radiographic images, it may be
visualized in the midline and over the roots of the
canines, premolars and molars.
Developmental Anomalies of the Skull
and Jaws
Mandibular Tori
Mandibular tori represent benign overgrowths of
mature, lamellar bone, occurring on the lingual
mandibular cortex. Typically attached to the
mandible opposite the premolar region and
superior to the mylohyoid line, they are most
commonly bilateral. There is some variation in
incidence among races with a higher incidence
among Orientals than in Caucasians. Apparently,
genetic factors also influence tori development, as
Stafne Bone Cavity
The Stafne cavity is an osseous defect caused by
pressure of the submandibular salivary gland on
the mandible during its development. It is a well23
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Figure 59. Radiographic Image of Mandibular Tori
Figure 60. Maxillary Torus
defined radiolucency found at the angle of the
mandible below the mandibular canal that has no
significance except in its differentiation from other
conditions (Figure 62).
Clefts
Developmental clefts of the palate are not
uncommon. They result from a smooth defect
and are often associated with marked tooth
displacement.
Conclusion
Many conditions of the hard and soft tissues
of the oral cavity and surrounding area can
be diagnosed and treated through the use of
quality, diagnostic dental radiographic images.
The importance of quality dental radiographic
images cannot be overstated and is covered in
other continuing education courses offered by
the American Dental Assistants Association. It
is important that the whole dental team have
Figure 61. Radiographic Image of Maxillary Torus
the ability to recognize anomalies shown in
radiographic images. Early detection of any
dental disease offers the best prognosis for the
patient and continues the quality of care every
patient deserves.
Figure 62. Stafne Bone Cavity
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Course Test Preview
To receive Continuing Education credit for this course, you must complete the online test. Please go to:
www.dentalcare.com/en-us/dental-education/continuing-education/ce433/ce433-test.aspx
1.
The carious lesion on the canine tooth in this radiographic image involves the ____________.
a. enamel only
b. dentin only
c.pulp
d. enamel and dentin
2.
_______________ affects the molar in this radiographic image.
a. Horizontal bone loss
b. Vertical bone loss
c.Osteosclerosis
d.Attrition
3.
The radiolucency at the apex of tooth #8 in this radiographic image could be a/an ____________.
a.abscess
b.cyst
c.granuloma
d. All of the above.
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4.
The radiopacity right of the molar in this radiographic image is ____________.
a. a root fragment
b. condensing osteitis
c.calculus
d. a maxillary torus
5.
The radiolucency across the incisor in this radiographic image is _______________.
a. a fracture of the tooth root
b. a transverse carious lesion
c. a fingernail crimp artifact
d. horizontal bone loss
6.
The radiopacity found in this radiographic image and located beyond the root apex of the
premolar is _______________.
a.calculus
b. an enamel pearl
c. an impacted supernumerary tooth
d.osteosclerosis
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7.
This tooth anomaly is a result from ____________________.
a. fusion or gemination
b.evagination
c.invagination
d. a fracture
8.
_______________ is a regressive change illustrated in this radiographic image.
a. Internal resorption
b. External resorption
c.Ankylosis
d.Hypercementosis
9.
A _______________ most likely caused the radiolucency in the patient’s left mandible in
this radiographic image.
a. circular fracture
b. talon cusp
c. mandibular tori
d. Stafne bone cavity
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10. _______________ is the apical radiopacity at the base of the premolar in this radiographic
image.
a. Condensing osteitis
b. External resorption
c. A root fragment
d. Cervical burnout
11. A diligent search for recurrent caries should be made when radiographic images reveal
_______________.
a. open margins on restorations
b. interproximal restoration overhangs
c. restorations which appear to end short of the preparation margins
d. All of the above.
12. A normal anomaly of the X-ray process which sometimes causes an image that looks
suspiciously like interproximal caries is _______________.
a. proliferative gingival hyperplasia
b. dental calculus
c. vertical bone loss
d. cervical burnout
13. Disorders that may clinically show a peculiar translucent appearance with discoloration
ranging from brown to yellow to gray is/are _______________.
a. dentinogenesis imperfecta
b. amelogenesis imperfecta
c. Turner’s hypoplasia
d. All of the above.
14. ____________ is an anatomical abnormality in which a tooth’s pulp chamber is elongated,
enlarged, and extends into the region of the roots.
a.Taurodontism
b.Hemihypertrophy
c.Lobulated
d.Ossification
15. Dilaceration is a _______________.
a. unusual bend in the tooth crown
b. unusual bend in the tooth root(s)
c. v-shaped space between curved adjacent surfaces of teeth
d. disease condition
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16. Epithelial remnants (builder’s debris) can proliferate within an apical granuloma to form a/an
_______________.
a. apical or lateral radicular cyst
b.macrodont
c. pulp stone
17. _______________ is/are associated with the Tooth of Mummery.
a. Pulp stones
b. Impacted supernumerary molars
c. Internal resorption
d. Periapical granuloma
e. Pyramidal teeth
18. ____________ are teeth numbering in excess of the 32 permanent or 20 deciduous teeth.
a.Macrodonts
b.Microdonts
c.Hypodonts
d.Supernumeraries
19. Mineralized plaque seen opposite the salivary ducts is _______________.
a. proliferative gingival hyperplasia
b. dental calculus
c. an enamel pearl
d. a talon cusp
e. early concrescence
20. _______________ is a congenital disease characterized by the presence of only three or four
teeth, the absence of eyebrows and eye lashes, and wrinkled palms.
a. Ectodermal dysplasia
b. Hutchinson’s syndrome
c. Kleinfelter’s syndrome
d. Facial hemihypertrophy
e. Turner’s syndrome
21. Maxillary torus are present in approximately ________ of the population.
a.66%
b.33%
c.15-18%
d.10%
e.25%
22. Gingival enlargements can occur as a result of ____________.
a.plaque
b.calculus
c. extrinsic factors
d. All of the above.
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23. _______________ is bone loss which demonstrates remarkable variation in height relative to
the adjacent tooth crowns.
a. Internal resorption
b. Vertical bone loss
c. Socket sclerosis
d. Bundle bone
24. _______________ is the laying down of excess bone in an extraction socket.
a. Incomplete healing
b. Socket fibrosis
c. Socket sclerosis
d. Bundle bone
25. A tooth with the notched appearance of a screwdriver is known as _______________.
a. Hutchinson’s tooth
b. Turner’s tooth
c. Tooth of Mummery
d. Kleinfelter’s tooth
e. Talon’s tooth
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References
No references cited.
Additional Resources
• Bath-Balogh M, Fehrenbach M. Illustrated Dental Embryology, Histology, and Anatomy, 3rd ed. 2011.
Elsevier Saunders.
• Bird DL, Robinson DS. Modern Dental Assisting, 10th ed. 2012. St. Louis, MO: Elsevier Saunders.
• Iannucci J, Jansen-Howerton L. Dental Radiography Principles and Techniques, 4th ed. 2012. St.
Louis, MO: Elsevier Saunders.
About the Authors
Allan G. Farman, BDS, EdS., MBA, PhD
Dr. Farman is Professor of Radiology and Imaging Science, Department of Surgical
and Hospital Dentistry at the University of Louisville. He is a Diplomate of the
American Board of Oral and Maxillofacial Radiology and a licensed specialist in that
discipline. He conducts private practice of maxillofacial radiology and has been
involved with digital dental imaging since its inception almost two decades ago. In his
private practice he interacts with all disciplines within dentistry and is familiar with the
needs of practitioners. He was recipient of the 2006 President’s Medal (University of
Louisville) for Distinguished Service. Dr. Farman is also Honored Guest Professor of Peking University,
China. He is the voting Representative for the American Dental Association to the International DICOM
(Digital Imaging and Communications in Medicine) Standards Committee. He also founded and Chairs
the International Congress and Exposition on Computed Maxillofacial Imaging and is Scientific Editor for
the American Academy of Oral and Maxillofacial Radiology. He is widely published and lectures both
nationally and internationally.
Sandra A. Kolsom, CDA-Emeritus, RDA
Sandra is a Dental Radiography Instructor at City College of San Francisco and Santa
Rosa Junior College. Ms. Kolsom is also Director of the Auxiliary Productivity training
and a clinical consultant for Ultimate Potential Dental Personnel Service. In addition,
she remains active in the dental field on a part-time basis in an orthodontic practice.
Ms. Kolsom also has over seven years of experience as a dental assisting instructor.
Her past dental assisting experience includes periodontics, general dentistry, oral
surgery, endodontics and orthodontics. Other related activities include past President
and Chairman of the Board for Temporary Fillings, Inc., a placement agency for temporary support staff;
Advisory Committee Member for Santa Rosa Junior College Dental Assisting Program; and has reviewed
new textbooks for Lippencott Publishing Company.
ADAA 2013 Council on Education
Members of the Council on Education of the American Dental Assistants Association
helped with the revision of this course. All members of the Council on Education are
ADAA Active or Life Members with an interest in dental assisting education. Each one
volunteers their time to the lifelong learning of dental assistants.
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