This document discusses apical periodontitis, including its definition, causes, prognosis, and epidemiology. Some key points: - Apical periodontitis is an inflammatory response to infection of the root canal system, which can include both acute and chronic phases. - The prognosis of endodontic treatment depends on preventing apical periodontitis by eliminating root canal infection. - Epidemiological studies show the prevalence of apical periodontitis varies widely between populations, from 20-80% depending on factors like access to dental care. - Reasons for tooth extraction often include apical periodontitis and failed endodontic treatment, though historically it has not been well recognized as a disease. Progn

1. APICAL PERIODONTITIS

2. Prognosis
• is the
prospect of recovery
as anticipated from the
usual course of disease
or
peculiarities of the case
m-w.com

3. Prospect of Recovery
• From disease to health
–from pulpitis to freedom from
pain and infection – by
regeneration or replacement
–from apical periodontitis to
normal apical periodontium – by
regeneration

4. Prognosis - Outcome
• Outcome studies may also address
the function and survival of the
treated tooth
Caplan & Weintraub, 1997

5. Treatment of
apical periodontitis
Prevention of
apical periodontitis
Common purpose:
No root canal infection; no apical periodontitis.
This is what we usually think of when we say “prognosis of
endodontic treatment”

6. Pulpitis
• .. is tissue reactions to trauma
and/or infections of the pulp-dentin
organ
• .. includes acute and chronic
phases, abscesses, but may be
reversible

7. Effective prevention is possible only when you know the etiology and
pathogenesis of the disease in question, so..
Vital Pulp Treatment
The prognosis of
endodontic treatment of
teeth with initially vital
pulps or uninfected
necrotic pulps is
unrelated to the pulp; it
is a matter of preventing
apical periodontitis

8. What is Apical Periodontitis?

9. Apical Periodontitis
• .. is tissue reactions to trauma and/or
infection of the root canal system
• .. includes acute and chronic phases,
abscesses and radicular cysts
• ..that persists is a sign of infection of the
root canal system

10. Why Apical Periodontitis?
• A defense
mechanism
developed for the
protection of the
body interior from
life-threatening
infections
• Transition from
continuously
shedding to
permanent teeth
with pulps

11. Apical Periodontitis
2008
1200

12. Apical Periodontitis
How well do we do? What is the status of apical periodontitis in
the population at large? We need to respond to such issues.
When treating
individual patients,
epidemiology is of little
concern, and prognosis
of interest only in
predicting the fate of
that particular tooth.
But as a profession, we
will be judged by how
well we can control and
eliminate the disease.

13. Fig. 6. The prevalence of apical periodontitis in different populations.
a, Dugas et al 2003; b, Marques et al 1998; c, Frisk & Hakeberg 2005; d, Loftus et al 2005; e, Buckley &
Spangberg 1995; f, DeCleen et al 1993; g, Eriksen et al 1991; h, Dugas et al 2003; i, Kirkevang et al 1991; j, Frisk
& Hakeberg 2005; k, Chen et al 2007; l, Jiménez-Pinzón et al 2004; n, De Moor et al 2000; o, Saunders et al 1997;
p, Sidaravicius et al 1999; q, Tsuneishi et al 2005; r, Kabak & Abbott 2005; s, Segura-Egea et al 2005.
a b
c d e
f g h i j
k
l
n
o p q
r s
0
20
40
60
80
100
Individuals
with
AP,
%
Adapted from: Harald Eriksen 2008
in: Ørstavik & Pitt Ford, Essential
Endodontology

14. Epidemiology
Prevalence of apical periodontitis %,
selected countries, age 35-45 years
0
10
20
30
40
50
60
70
80
%
Portugal
Norway
Lithuania
From Eriksen et al., 2002
Many extractions;
moderate quality
Few extractions;
moderate quality
Few extractions;
poor technical quality

15. Harald Eriksen 2008
in: Ørstavik & Pitt Ford,
Essential Endodontology
Maintaining a high
number of retained
teeth into old age is a
goal common to all of
dentistry;
Endodontology deals
with bringing down the
prevalence of apical
periodontitis

16. Reasons for Extraction
• In a survey of 31 investigations dealing with reasons for
extraction of permanent teeth, in only three was apical
periodontitis mentioned explicitly as the reason for
extraction. One of them was an investigation performed
by Brekhus as early as 1929. An interesting observation
was that some additional investigations mentioned
“failed endodontic treatment” and “pain” as reasons for
extraction without explicitly defining pulpitis or apical
periodontitits. It can therefore be concluded that
apical periodontitis has not been appreciated as a
“disease” compared to, for instance, marginal
periodontitis, but rather considered as a sequel to
dental caries.
Harald Eriksen in: Ørstavik & Pitt Ford, Essential Endodontology 2008

17. Reasons for Extraction
Caries
Pulp/AP Perio
0
4
8
12
16
20
Per cent
Brennan DS, Spencer AJ, Szuster FS. Provision of extractions by main diagnoses. Int Dent J. 2001 Feb;51(1):1-6.
Australia: Practitioners completed service logs over one to two typical clinical days.

18. Reasons for Extraction
Caries
Pulp/AP
Perio Caries
Pulp/AP
Perio
1
3
5
7
Odds ratio
18-44 år 45+
Brennan DS, Spencer AJ, Szuster FS. Provision of extractions by main diagnoses. Int Dent J. 2001 Feb;51(1):1-6.
Australia: Practitioners completed service logs over one to two typical clinical days.
”On the road to damnation”
”On the road to salvation”

19. Reasons for Extraction
Caries
Pulp/AP
Perio Pulp/AP
Perio
Pulp/AP
Perio
0
10
20
30
40
50
Per cent
overall urban rural
Spalj S, Plancak D, Jurić H, Pavelić B, Bosnjak A. Reasons for extraction of permanent teeth in urban
and rural populations of Croatia. Coll Antropol. 2004 Dec;28(2):833-9. Survey among practitioners.

20. Reasons for Extraction of
Endodontically Treated Teeth
Caplan DJ, Weintraub JA. Factors related to loss of root canal filled
teeth. J Public Health Dent. 1997 Winter;57(1):31-9.
No. of approximal contacts .000
Age .000
No. of missing teeth .000
Anxiety .002
Bridge abutment .006
Medication .007
Diabetes .022
Denture/partial .037
Poor hygiene .039

21. Fig. 6. The prevalence of apical periodontitis in different populations.
a, Dugas et al 2003; b, Marques et al 1998; c, Frisk & Hakeberg 2005; d, Loftus et al 2005; e, Buckley &
Spangberg 1995; f, DeCleen et al 1993; g, Eriksen et al 1991; h, Dugas et al 2003; i, Kirkevang et al 1991; j, Frisk
& Hakeberg 2005; k, Chen et al 2007; l, Jiménez-Pinzón et al 2004; n, De Moor et al 2000; o, Saunders et al 1997;
p, Sidaravicius et al 1999; q, Tsuneishi et al 2005; r, Kabak & Abbott 2005; s, Segura-Egea et al 2005.
a b
c d e
f g h i j
k
l
n
o p q
r s
0
20
40
60
80
100
Individuals
with
AP,
%
Segura-Egea JJ, Jiménez-Pinzón A, Ríos-Santos JV, Velasco-Ortega E,
Cisneros-Cabello R, Poyato-Ferrera M. Int Endod J. 2005 Aug;38(8):564-9.
High prevalence of apical periodontitis amongst type 2
diabetic patients. Department of Stomatology, School of Dentistry,
University of Seville, Seville, Spain.
RESULTS: Apical periodontitis in at least one tooth was
found in 81.3% of diabetic patients and in 58% of control
subjects (P = 0.040; OR = 3.2; 95% CI = 1.1-9.4). Amongst diabetic
patients 7% of the teeth had AP, whereas in the control subjects 4% of teeth
were affected (P = 0.007; OR = 1.8; 95% CI = 1.2-2.8). CONCLUSIONS:
Type 2 diabetes mellitus is significantly associated with an increased
prevalence of AP.

22. Reasons for Extraction of
Endodontically Treated Teeth
Caplan DJ, Weintraub JA. Factors related to loss of root canal filled
teeth. J Public Health Dent. 1997 Winter;57(1):31-9.
Periodontal disease .066
History of trauma .075
Cuspal coverage .096

23. Loss of Endodontically Treated
Teeth
Caplan DJ, Cai J, Yin G, White BA. Root canal filled versus non-root
canal filled teeth: a retrospective comparison of survival times. J
Public Health Dent. 2005;65(2):90-6.

24. Loss of Endodontically Treated
Teeth
Salehrabi R, Rotstein I. Endodontic treatment outcomes in a large
patient population in the USA: an epidemiological study. J Endod.
2004 Dec;30(12):846-50.
…treatment done in 1,462,936 teeth of
1,126,288 patients from 50 states across the
USA was assessed over a period of 8 yr.
…….
Overall, 97% of teeth were retained in the
oral cavity 8 yr after initial nonsurgical
endodontic treatment.

25. Loss of Endodontically Treated
Teeth
Salehrabi R, Rotstein I. Endodontic treatment outcomes in a large
patient population in the USA: an epidemiological study. J Endod.
2004 Dec;30(12):846-50.
Analysis of the extracted teeth revealed that
85% had no full coronal coverage. A
significant difference was found between
covered and noncovered teeth for all tooth
groups tested (p < 0.001).

26. Loss of Endodontically Treated
Teeth
Salehrabi R, Rotstein I. Endodontic treatment outcomes in a large
patient population in the USA: an epidemiological study. J Endod.
2004 Dec;30(12):846-50.
The combined incidence of untoward events
such as retreatments, apical surgeries, and
extractions was 3% and occurred mostly
within 3 yr from completion of treatment.

27. Loss of Endodontically Treated
Teeth: Primary Teeth
Rocha MJ, Cardoso M. Survival analysis of endodontically treated
traumatized primary teeth. Dent Traumatol. 2007 Dec;23(6):340-7.
51 teeth, 10-60
months of age 0
10
20
30
40
50
60
70
80
90
100
0–6
7–12
13–18
19–24
25–30
31–36
37–42
43–48
Time from treatment, months
Per
cent
of
treated
teeth
Failure (%) Cumulative success %

28. Reasons for Extraction of
Endodontically Treated Teeth
Wegner PK, Freitag S, Kern M. Survival rate of endodontically treated teeth
with posts after prosthetic restoration. J Endod. 2006 Oct;32(10):928-31.

29. Usual Course of Disease
• Prognosis assessment is impossible
without knowing the ”natural
history” of AP:
• The infectious process
• The inflammatory response
• Variations and deviations from case
to case

30. The Infectious Process
• Sources of infection
– Caries – diminishing importance
– Physical exposure – filling margins, previous
pulp/dentin trauma
– Traumatic fractures – special concerns
– Anachoresis – questionable occurrence
• Relative importance? – few/no data
– Public health perspective: adequate conservative
treatment is the best prevention of apical periodontitis

31. The Infectious Process
• Sites of established infection
– Main pulp canal space and walls
– Accessory canals and apical delta
– Dentinal tubules
– Cementum surface
– Extraradicular colonizations
• Relative importance? – few data, but
the root canal infection is of course paramount
– Brynolf 1966, Langeland et al. 1977

32. The Infectious Process
Pulpitis Necrosis
Canal
infection
Apical
periodontitis
Time
Spread to
apex
Increasing infectious load;
increasingly difficult to treat

33. Further course of
disease:
Sequels to the
initial events

35. Severity
Incidence Adielsson et al 1999

36. The Inflammatory Response
• Acute and chronic
– Acute AP
– Chronic AP: primary, persistent, secondary
– Exacerbating AP: Phoenix abscess
– Acute periapical abscess
– Chronic periapical abscess with sinus tract
– Radicular cyst: detached or pocket cyst

37. Time-Course of Apical
Peridontitis
• Dynamics of pulpal infection
• Bacterial succession and variations in
virulence and pathogenicity
• Host factors modulating inflammation
and spread of the infection
• Ultimate consequences of root canal
infection

38. Percentage of teeth at risk of
developing apical periodontitis
Ørstavik 1994
0
2
4
6
8
0 1 2 3 4
TIME, years
ROOTS,
per
cent
AP % of at risk General risk* Risk for RF teeth* Risk for noRF teeth*
0
2
4
6
8
0 1 2 3 4
TIME, years
ROOTS,
per
cent
AP % of at risk General risk* Risk for RF teeth* Risk for noRF teeth*

39. Percentage of teeth at risk of
developing apical periodontitis
Ørstavik 1994
0
2
4
6
8
0 1 2 3 4
TIME, years
ROOTS,
per
cent
AP % of at risk General risk* Risk for RF teeth* Risk for noRF teeth*
0
2
4
6
8
0 1 2 3 4
TIME, years
ROOTS,
per
cent
AP % of at risk General risk* Risk for RF teeth* Risk for noRF teeth*

40. Time-Course of Apical
Peridontitis
• Bacterial succession and variations in
virulence and pathogenicity
– Primary infection – self-explanatory
– Persistent infection – original flora, no cure
– Recurrent infection – residuals reemerging
– Secondary infection – new infection through
leaking root filling

41. Natural Course of the Disease:
Pain
• Varying in intensity and severity
– Pain sometimes accompanies pulpitis and apical
periodontitis
• Unpredictable if untreated
– Pulpitis and acute apical periodontitis dominate as
sources for acute dental pain in children and adults
(Zeng et al 1994, Lygidakis et at 1998) which may be
debilitating to the patient and lead to absence from
work and involvement of costly health services.
(Ørstavik, 2009)

42. Natural Course of the Disease:
Pain
• Unpredictable if untreated
– While we know that emergency dental services are in
great demand in most countries, in urban as well as
rural areas, there is very scant information on the
actual incidence and prevalence of acute pulpal and
apical periodontal disease. Therefore, one can only
speculate that there is still, even in communities with
well-developed dental services, a significant impact
on the general well-being by acute pulpal and
periodontal conditions (Sindet-Pedersen et al 1985,
Richardsson 2005). (Ørstavik 2009)

43. End-Points of Root Canal
Infections
• Immediate abscess and sinus tract formation: incidence?
• Chronic, stable encapsulation: prevalence known
• Chronic cyst formation: prevalence known
• Exacerbation of chronic lesion: incidence (5% per year?)
• Sinus tract formation: incidence?
– Any available surface, sinus, nose, mucosa, skin
• Spreading oral infection: incidence?
– Submandibular, sublingual, local fascies
– Eyes, brain, mediastinum
20-70%
}

44. Natural Course of the Disease:
Conclusions
• Unpredictable if untreated
• It does not heal
• Potentially very painful
• Serious complications/sequelae are rare
Pulpitis ->Necrosis->Apical Perio->Acute phases->Local spread->Systemic spread
Filling therapy Endodontics Extraction