Dental education - definitions of various conditions and presentations of endodontically involved teeth

1. 1
Diseases of the Pulp &
Peri-apical Tissues
An encounter between root canal
infection and host response
Prepared by Dr Lea Foster
3
1 2
1
e.g. Shallow caries, leaking rest.
Persistent irritation
Bacterial invasion
Irreversible pulpitis
Reversible pulpitis
Reversible pulpitis

2. 2
Reversible Pulpitis
Vital pulp
Local areas of inflamed tissue – will heal
after irritant is removed
Restore caries, re-do leaking rest., treat
exposed dentine
Symptoms can be misleading
On thermal stimulation – may be no, to very
intense sharp response
Reversible pulpitis
Symptoms – Patient often reports
sens. to cold foods/drinks
Signs
Tests
Cold: increased response compared to
normal
Possible slight sens. to percussion
Radiography
Normal appearance – normal perio.
ligament width
4
Reversible pulpitis
Irreversible pulpitis
Irreversible Pulpitis
Pulp is vital but severely inflamed
Healing is unlikely with conservative
treatment
Pulp necrosis and infection in the root
canal is the likey outcome if conservative
treatment is attempted
If untreated will lead to apical
periodontitis
Irreversible Pulpitis
Symptoms – can be misleading
May be asymptomatic? 26 – 60% cases 4
See this reference for more detail on how this can occur
If symptomatic – tooth is very sensitive to
thermal changes
Cold, hot and pain will often linger after
stimulation4
See this reference for more detail on how this can occur
The longer it has been symptomatic, the
more severe the pain & any history of
spontaneous pain – more likely irreversible
pulpitis

3. 3
Irreversible pulpitis
Signs and symptoms
Tests
Cold: increased response
Hot: increased response
Lingering pain after thermal stimulation
Spontaneous pain
Radiographic signs
Normal or possible widened ligament
The more long-standing the condition the more
potential for inflammation of apical tissues
1
a) Clinically normal
No symptoms
No signs
Normal PDL width
No loss of lamina
dura
No loss of bone
density periapically
No resorption of
dentine
Responds WNL to
tests
Clinically normal
Thin PDL
Apical Periodontitis
Peri-apical tissue reactions are
directly related to the bacterial
invasion of the root canal5
b) Apical periodontitis
Acute
1.Primary - 1°
2.Secondary -
2° (or acute exacerbation)
Chronic
1.Granuloma
2.Condensing
osteitis
Inflammation of the periapical tissues

4. 4
1
e.g. Shallow caries, leaking rest.
Irreversible pulpitis
Reversible pulpitis
Granuloma
OR
Condensing
Osteitis
Persistent irritation
Bacterial invasion
1° Acute apical periodontitis
In only on instance can be sterile – bruxism
OR if bacteria are involved
Occurs when bacteria invade the root
canal for the first time
Bacterial invasion is a dynamic encounter
with host tissue
Host tissue can mobilise barriers
anywhere inside the pulp space
More long-standing lesion – greater
likelihood for bacteria to gain ground
1° Acute apical periodontitis
Signs & symptoms
Tooth becomes tender to percussion (TTP)
Tooth may still display signs of
irreversible pulpitis
Tooth may be unresponsive to
thermal/electric testing (completely non-
vital)
Radiographically – normal PDL or Slightly
widened
1° Acute apical periodontitis
Slightly widened PDL
7
1
4
2° Acute apical periodontits
Acute exacerbation
of a chronic
condition
Pulp completely
non-vital
TTP
No response to
thermal or electric
testing
7

5. 5
Chronic apical periodontits
Apical granuloma
Tooth is often
symptom free but
may have low
grade symptoms
that come and go
Tooth gives no
response to thermal
or electric tests
May exhibit slight
TTP
Granulation
tissue
Fibrous
tissue –
black arrows
8
Granulation tissue
Fibrous tissue
Granulation tissue
Accumulation of
neutrophils - microabscess
8
Chronic apical periodontits
Condensing osteitis
A possible response to
long-standing
irreversible pulpitis or a
non-vital infected pulp
space
Condensing osteitis
Signs and symptoms
May have mildly heightened sensitivity to
thermal stimuli (irreversible pulpitis)
May have no response to thermal /
electric stimuli (non-vital)
May or may not have sensitivity to
percussion
Radiopaque lesion associated with root
apices

6. 6
c) Periapical cyst
True cyst Pocket cyst
1
Periapical cysts
Cyst - a sequel to a peri-apical
granuloma
Not every apical granuloma will
become a cyst
Pocket cyst – thought to have the
potential to heal with conventional
RCT
True cyst – thought to require
surgical treament to excise the lesion
29-43% contain cholesterol crystals –
may prevent spontaneous repair
1
Cholesterol crystals
CT – connective
tissue
NT – necrotic
tissue
D – dentine
CC – cholesterol
crystals
9
Cysts
Signs & symptoms
Similar to other Chronic lesions
TTP or maybe not
Tender to palpation over buccal/labial
aspect of alveolus or maybe not
Tooth not responsive to thermal/electric
stimuli
Clearly demarcated, rounded lesion
associated with apex of tooth
d) Periapical abscess
Acute abscess
1. Primary (1°)
2. Secondary (2°)
Chronic abscess
(with sinus)

7. 7
1° Acute Apical Abscess
Signs & symptoms
Tooth xt. sens. to
percussion/touch
No response to
thermal/electric (non-
vital)
Tender to palpation
over buccal tissues
Possible radiographic
lucency – widened
ligament –diffuse
appearance (unlike
cyst)
Accumulation of
inflammatory exudate
Develops as a sequel to primary
acute apical periodontitis
2° Acute Apical Abscess
Signs & symptoms
Tooth xt. sens. to
percussion/touch
No response to
thermal/electric (non-
vital)
Tender to palpation
over buccal tissues
Radiographic lucency
– widened ligament –
diffuse appearance
(unlike cyst)
Accumulation of
inflammatory exudate
Develops as a sequel to 2°
acute apical periodontits or
chronic apical periodontitis
7
Acute abscess (1° & 2°)
The abscess is
‘pointing’ but has
not drained yet
Fluctuant swelling
Chronic apical abscess
With draining sinus
Signs & symptoms
Low grade symptoms
Maybe slight TTP
No response to
thermal/electric tests
Periodic bad taste in
mouth
May be slight to no
tenderness to
palpation
3

8. 8
e) Facial cellulitis
Firm swelling
Facial cellulitis
May be a sequel to:
1° acute apical abscess
2° acute apical abscess
Chronic abscess
Instead of draining via sinus to oral
cavity or externally onto the face,
spreads along fascial planes of the
face, head and neck
Can have serious complications
Systemic complications
Osteomyelitis, Ludwig’s angina,
Actinomycosis, Orbital cellulitis,
Cavernous sinus thrombosis, Brain
abscess, Mediastinitis, Neural
complications
When bacterial toxins enter blood
stream – Septic shock, Bacteraemia,
Septicaemia
Cellulitis - radiographic appearance
Tooth may or may not exhibit apical
radiolucency
Depends on whether it is a sequel to 1°
apical abscess, 2° apical abscess
Tooth will exhibit necrotic infected
pulp or will be pulpless with infected
root canal system
Signs & symptoms
Similar to those of apical abscess
f) Extra-radicular infection
Micro-organisms establish colonies on
external root surface within the periapical
region1
Sequqel to infected root canal system or
previous RCT – extra-radicular species
similar to those found in the root canal
Signs & symptoms
No symptoms or similar to those of apical
abscess – acute or chronic
Radiographic appearance similar to granuloma,
abscess, cyst or peri-apical scar
Extra-radicular infection
Peri-apical actinomycosis

9. 9
Extra-radicular organisms found in
the following situations
Apical abscess, long-standing draining
sinus, infected radicular cysts (esp.
pocket cysts), peri-apical actinomycosis
and with infected dentine pieces that
have been displaced into apical
periodontal tissues during RCT
Extra-radicular infection Extra-radicular infection
Diagnosed by histological
examination of the tissue removed
during apical surgery
If symtoms persist after conventional
RCT – extra-radicular infection or cyst
must be suspected
g) Foreign body reaction
Inflammatory response to foreign
material in peri-apical tissues
Often root canal obturation material
Other materials – talcum powder from
gloves, cellulose fibres from paper points
Not visible radiographically
Appearance may be radiolucent lesion
similar to inflammation from an
infectious process
Extruded
obturation
material does
not always
result in
foreign body
reaction
Foreign
body
reaction
Foreign body reaction to Cellulose
FB – paper point
RT – root tip
EP – epithelium
BP – bacterial
plaque
PC – plant cell
9
h) Periapical scar
Neither disease or pathological condition
Healing response without bone deposition
following treatment of a lesion which has caused
bone resorption
Granuloma, cyst, abscess, extra-radicular
infection or foreign body reaction10
Majority seem to be associated with surgical
defects
Appear as radio-lucencies located at a distance
from the root apex
Most commonly affected – upper laterals with
‘through and through’ defects – involving both
palatal and labial cortical plates – heal with
connective tissue ingrowth11

10. 10
References
1. Classification, diagnosis and clinical manifestations of apical periodontitis Paul V Abbott
Endodontic Topics 2004:8:36-54
2. Sundqvist, Figdor Life as an Endodontic pathogen Endodontic Topics 2003, 6, 3-283.
3. Apical periodontitis: a dynamic encounter between root canal infection and host response
p.N. Nair Periodontology 2000 1997:13:121-148
4. Pulpal diagnosis Sigurdsson Endodontic Topics 2003:5:12-25
5. Pulpal and periapical tissue responses in conventional and mono-infected gnotobiotic rats
Kakehashi et.al. Oral Surg 1974:37:783-802
6. Bacteriological studies of neccrotic pulps Sundqvist Umea University Odontological
Dissertations No. 7 1976
7. Urgent Care in the Dental Office: An Essential Handbook Terezhalmy, Geza T
QuintessencePublishing (IL), 011998. 7.2.2).
8. Light microscopic study of periapical lesions associated with asymptomatic apical periodontitis
S.L. Kabak, Y.S. Kabak, S.L. Anischenko Ann Anat 187 (2005) 185—194
9. Non-microbial etiology: foreign body reaction maintaining posttreatment apical periodontitis
P.N. RAMACHANDRAN NAIR
10. Persistent Periapical radiolucencies of root-filled human teeth, failed endodontic treatments,
and periapical scars Nair PNR, Sjo¨gren U, Figdor D, Sundqvist G.. Oral Surg Oral Med Oral
Pathol Oral Radiol Endod 1999: 87: 617–627
11. A multivariate analysis of the influence of various factors upon healing after endodontic
surgery Rud J, Andreasen JO, Mo¨ller Jensen JE.. Int J Oral Surg 1972: 1: 258–271