1. ANATOMIC PERIAPICAL
RADIOLUCENCIES(FALSE)
TRUE PERIAPICAL
RADIOLUCENCIES
Marrow spaces and
hematopoietic defect of the
jaws
Sequelae of pulpitis
Granuloma
Dental papilla Radicular cyst
Maxillary sinus Scar
Incisive foramina and canals Chronic and acute
dentoalveolar abscess
Nasolacrimal duct Surgical defect
Naris Cholesteatoma
Greater palatine foramen Osteomyelitis
Mental foramen Dentigerous cyst
Submandibular fossa Periapical cementoma
Mandibular canal Periodontal disease
Traumatic bone cyst
Nonradicular cyst
Malignant tumors
2. TRUE PERIAPICAL RADIOLUCENCIES represents
lesions that are truly located in contact with apex of a
tooth
Their shadow cannot be shifted from the periapex by
taking additional radiographs at different angles
• FALSE PERIAPICAL RADIOLUCENCIES Are produced
by anatomic cavities or lytic bony lesions that donot
contact the apex of a tooth
The radiolucent shadows may be shifted from the
periapex by taking additional radiograph at different
angles
8. Most common type
Result of a successful attempt by the periapical tissues to
neutralize and confine the irritating toxic
products(prostaglandins,kinins,lysosomes and endotoxins)that
are escaping from the root canal
Low grade inflammation
Microstructure consists of proliferating endothelial
cells,capillaries,young fibroblasts,a minimal amount of collagen and
chronic inflammatory cells
FOUR TYPES ON BASIS OF HISTOPATHOLOGY
Exudative
Granulomatous
Granulofibrous
fibrous
9. Radiographically,lesion is a rather well circumscribed
radiolucency somewhat rounded in shape and surrounding
the apex of the tooth
May or may not have a thin
radiopaque(hyperostotic)border.
Radiographs reveal presence of deep restorations,extensive
caries,fractures or a narrower pulp canal
Periapical radiolucency of diameter less than 1.6cm is
considered as periapical granuloma
Electrical and thermal pulp testing will usually indicate
that pulp is non-vital
10. Tooth is completely asymptomatic
Absence of sensitivity to percussion
Crown may have darker colour than of its neighbours
because of blood pigments that have diffused into
empty dentinal tubules
Swelling and expansion of cortical plate is unusual
since they rarely reach a size to produce such an effect
11. GRANULOMA
Small round or oval
radiolucency <1.6cm in
diameter surrounding apex
of tooth with or without
well-circumscribed borders
12. Second most common
Inflammatory cyst
Origin from cell rest of Malassez
Orginate in pre-existing periapical granuloma
As the masses of proliferating epithelial nests increase in size,
the central cells start to degenerate and liquefy
Leads to liquid-filled cavity lined with epithelium
Cysts continues to grow because of a combination of factors
1. The products from the cell lysis are probably irritating and may
provide growth stimulus
2. Epilthelial cells discharged into the cyst lumen increase the
protein content and hence the osmotic pressure of cyst
13. fluid leading to more water diffusion into lumen
3. The pressure exerted by the enlarging cyst on the alveolar
bone induces osteoclastic action and resorption of the
periapical bone
FEATURES
The more pronounced the hyperostotic border of the
lesion, the more likely is the lesion to be a cyst
Should measure atleast 1.6cm in diameter
An untreated cyst may slowly enlarge and cause
expansion of cortical plates,observed clinically as dome
like swelling on the alveolus over the periapical region of
involved tooth
14. The swelling may develop on either the buccal or lingual side
of alveolar process and will be covered with normal-appearing
Mucosa
Initially,bony hard to palpation,but later it may demonstrate
A crackling sound(crepitus) as cortical plates become thinned
Usually,the cortical plates remain intact
Large cysts may involve a complete quadrant with some of the
Teeth occasionally mobile and some of the pulps non-vital
Root resorption is also seen
the causative tooth and the alveolar swelling are painless in
case of sterile cysts,however when infected develops pain
16. Well defined radiolucency at apex of untreated
asymptomatic tooth with nonvital or diseased pulp:90%
cases dental granuloma or radicular cyst(1.6cm or
more=radicular cyst)
PERIAPICAL SCAR: if well sealed, persistent
asymptomatic nonenlarging radiolucency associated with
teeth which received non-surgical endodontic treatment
for granuloma and cyst
Asymptomatic radiolucency persisting after root resection
can be either a scar or surgical defect
PERIAPICAL CEMENTOMA: pulp is vital and mostly
involve lower teeth ,mostly incisors
TRAUMATIC BONE CYST :pulp is vital and 90% occurs in
mandible(molar,premolar,incisor region)
17. Extraction
Conservative root canal therapy
Cyst respond well to nonsurgical endodontic treatment:2
theories
1. Instrumentation beyond apex permits the cyst to drain into
canal
2. When root canal is sealed the irritating products from
gangrenous pulp are no longer present and inflammation
subsides
Biopsy via buccal window to determine the nature of lesion
Apical curettage or root resection procedure if 2cm or
larger(radicular cyst)
Retrograde filling and periapical curettage if root canal is
nonnegotiable
18. For large radicular cysts with considerable bone loss
Surgical enucleation
Restoration of defect with graft,preferably autogenous
bone
Marsupialization
Decompression
Decompression with delayed enucleation
Creation of common chamber with maxillary sinus or
nasal cavity
Sequential post surgical radiographs to ensure
regression of defect
19. Composed of dense fibrous tissue
Situated at periapex of a pulpless tooth in which
rootcanals have been filled
Represented by granuloma,cyst or abscess whose healing
has stopped in the formation of dense scar tissue(cicatrix)
rather than bone
In some instances,granulation tissue during resolution
slowly organizes with production of more collagen fibers
leading to dense collagenous connective tissue scar
:permanent and radiolucent
Microscopically : few spindle shaped fibroblasts scattered
throughout dense collagen bundles
Scarring periapical granuloma: relatively young ,less dense
scar experiencing intermittent inflammation
20. Well circumscribed radiolucency that is more or less
round resembling granuloma and cyst radiographically
but usually smaller
Asymptomatic
Occurs mostly in anterior region of maxilla
Majority of involved teeth have been endodontically
treated
MANAGEMENT
No treatment required
22. Primary or neoteric abscesses: associated with teeth that have
not developed apparent radiolucent lesion
• Acute apical periodontitis/acute periapical abscess
Secondary or recrudescent abscesses: develop in a previously
existing asymptomatic periapical radiolucent lesion
PRIMARY ABSCESS:
Radiographically normal periapical region
Occurs due to rapid spread of virulent bacteria from canal to
periapical tissues
Very sensitive tooth and perhaps alveolar swelling
No resorption of bone due to sudden onset and course
Frequent swelling of the periodontal ligament which force the
tooth out slightly from its socket leading to an increased
periodontal ligament space around entire root
23. Chronic or acute type depending on
1. Number and virulence of invading organism
2. Resistance of host
3. Type and timing of treatment
MICROORGANISMS: Streptococci,Staphylococci,
Bacteroides, Peptococcus, Peptostreptococci,
Actinomyces, Eubacterium, Fusobacterium
24. RADIOGRAPHIC
periapical radiolucency is a feature of secondary abscess
Radiolucency may vary in size
Depending on duration ,acuteness and chronicity,margins
may be well defined with hyperostotic border to poorly
defined in chronic cases
Sometimes present as blurred area of lessened density than
surrounding bone
Deep restorations, caries, narrowed pulp chamber or canals
: suggestive of non-vital pulp
Roots may show resorption of apex
26. MICROSCOPICALLY
Central region of necrosis with dense
accumulation of PMN leukocytes surrounded by
inflamed connective tissue wall of varying thickness
CLINICALLY
Very painful to percussion
No response to electric pulp tests
Ice application relieves pain while heat aggravates
the pain
Progression leads to penetration of cortical plates,
formation of space infection and sinus tracts
Warmth of overlying skin or mucosa
Elevation of systemic temperature
27. A small proliferation of granulomatous tissue
often forms on the surface referred to as parules
pain subsides when drainage is established
COMPLICATIONS
Osteomyelitis
Septicemia
Septic emboli
Ludwig’s angina
Cavernous sinus thrombosis
28. Drainage established by opening pulp chamber and passing file
through canal into periapical region
If not possible,TREPHINATION procedure done:opening made
through mucosa and bone to abscess at apex
A THROUGH AND THROUGH DRAIN may be placed in abscess
in case of vestibular and lingual space infection along with
frequent irrigation with H2O2 solution and saline
sample of pus for culture and sensitivity test
Penicillin therapy(not less than 500mg qid for atleast 5
days)/erythromycin
Antibiotics before extraction
In case of draining sinus,exact location of the abscess can be
located by inserting a gutta-percha cone to the extent of sinus
and making radiograph of that area
29. Occurs in patients with periapical abscess with underlying
systemic disease or who have received large doses of
radiation therapy
Defined as an infection of bone that involves all 3
components: periosteum, cortex, and marrow
Osteitis: localized ; Osteomyelitis: diffuse
ACUTE OSTEOMYELITIS: Similar to acute primary
alveolar abscess, rapid onset and course, no bone
resorption, thus radiolucency may not be present
CHRONIC OSTEOMYELITIS: low –grade infection of bone
if untreated leads to extensive bone destruction,produces
radiolucent lesion
30. Chronic osteomyelitis demonstrate 4 distinct
radiographic picture
1. Completely radiolucent
2. Mixed radiolucent and radiopaque
3. Completely radiopaque
4. Garre’s osteomyelitis
FEATURES
Seldom observed in maxilla because of rich blood
supply
Tooth associated: non-vital pulp,may be sensitive
to percussion and previously associated with
periapical abscess
Periapical radiolucency somewhat rounded in
shape with poorly defined and ragged borders
31. Sequestrum present as radiopacity within a
radiolucency
Draining tract may be seen as radiolucency through
cortical plate beneath sinus opening on mucosa or
skin
Fever,malaise
Swelling on bone and mucosa around osteomyelitis
33. If area of bone destruction is large and region is not
painful:Eosinophilic granuloma:biopsy
If only alveolar portion of jawbone is infected:Alveolar
abscess
If tooth suspected is in fracture line or if an uncontrolled
systemic disease is present: Chronic Osteomyelitis
Paget’s disease: several bones with classic wool appearance
MANAGEMENT
Best treatment will be to extract the offending tooth rather
than conserving it by endodontic procedure
34. Arise from elements in periodontal ligament
Other names:
1. Periapical cemental dysplasia
2. Periapical osteofibroma
3. Periapical osteofibrosis
Arise on a reactive basis rather than on
neoplastic basis
3 stages in their development which are
radiographically apparent
35. 1. Early (osteolytic or fibroblastic)stage: radiolucent
2. Cellular fibroblastic stroma with small foci of
calcified material
2. Intermediate stage: radiolucent area containing
radiopaque foci
3. Final stage(mature lesion):well-defined solid
,homogeneous radiopacity surrounded in most
cases by thin radiolucent border
Calcified material may cementum,bone or
both(differentiated using polarising microscopy)
FEATURES
In early stage ,they occur as radiolucencies that
are somewhat rounded,have well-defined borders
and are associated with teeth having vital pulp
36. Blacks are commonly affected
80% occur in women
90% occur in mandible
Asymptomatic
Seldom exceeds 1 cm in diameter
MANAGEMENT
Treatment required only if
radiographic changes present
If infection or expansion of
cortical plate: Surgical enucleation
If inflammation of pulp:conservative
endodontic treatment
37. 1. Hemorrhagic bone cyst
2. Extravasation cyst
3. Simple bone cyst
4. Progressive bony cyst
5. Blood cyst
FALSE CYST(no epithelial lining)
Localized aberration in normal bone remodeling
or metabolism
38. FEATURES
A history of trauma may or may not be present
Asymptomatic except when it reaches size sufficient to
cause expansion of jaws
Well-defined cyst-like radiolucency above the mandibular
canal either round and positioned somewhat symmetrically
about periapex of root
OR
More elongated and oriented mesiodistally extending
superiorly between premolar and molar roots producing
scalloped appearance
No aspiration results but sometimes serosanguineous fluid
or some blood may be obtained
Mandible>Maxilla
Premolar-molar region most common location
39. TREATMENT
1. open the area surgically
2. Establish a diagnosis of traumatic bone cyst
3. Remove the tissue debris present
4. Curette the walls of bony cavity to induce bleeding
5. Close the soft tissue flap securely
Antibiotics
ALTERNATE METHOD:injecting venous blood into
bony defect(good results but objected because
sometimes in periodic radiographic follow-up
examination, the radiolucency is found to be
expanding)