Flare up is defined as pain or discomfort or swelling that requires an unscheduled patient visit and active intervention by the dentist.

1. GOOD
MORNING

3. Flare Up in
Endodontics
An example of chaos: A basic
overview and an evidence
based update

4. TABLE OF CONTENTS
Basic treatment
protocols
following the flare
up
MANAGEMENTETIOLOGYINTRODUCTION PREVENTION
02 0301 04
Brief introduction
to the concept
Incidence,
Criteria, Risk
Factors and
Causes for Flare
Up
How to avoid the
mishap

5. INTRODUCTION
"Happiness is your dentist telling you it won't hurt and
then having him catch his hand in the drill."
~ Johnny Carson
An ongoing and frequently vexing problem in
endodontics is the development of pain and
swelling during or after endodontic therapy.
An inter-appointment flare-up is an unhappy
event.
After an appointment, the patient calls or returns to
the dentist‘s office in distress.
This is upsetting to both the patient and the
dentist and is disruptive to a busy practice.

6. Endodontic
Inter
appointment
emergency
Endodontic
cellulitis
exacerbation
phenomenon
S
Y
N
O
N
Y
M
Inter-appointment flare up
Post-endodontic flare-up

7. DEFINITIONS
q Flare up is defined as an unscheduled emergency appointment necessitated by pain & swelling
combined or by either alone.
q Flare up is defined as pain or discomfort or swelling that requires an unscheduled patient visit
and active intervention by the dentist.
q Flare up is an acute exacerbation of an asymptomatic pulpal and/or periradicular pathosis after
the initiation or continuation of root canal treatment.
q Flare-up is moderate-to-severe postoperative pain or moderate to severe swelling that begins
12 to 48 hours after treatment and lasts at least 48 hours.
Pickenpaugh et al. (2001)
AAE (1998)
Walton & Foad (1992)
Morse (1990)

8. Int Endod J 2003;36:453-63.
A flare-up can be defined as pain and/or swelling of
the facial soft tissues and the oral mucosa in the area
of the endodontically treated tooth that occur within
a few hours or a few days following the root canal
treatment, when clinical symptoms (tooth pain when
biting, chewing or by itself) are strongly expressed
and the patient visits a health care institution sooner
than scheduled.

9. Inter-appointment Flare Up Criteria
ü Within a few hours to a few days after an endodontic procedure, a
patient has significant increase in pain or swelling or a combination of the
two.
ü The problem is of such severity that the patient initiates contact with the
dentist.
ü The dentist determines that the problem is of such significance that the
patient must come for an un- scheduled visit.
ü At the visit, active treatment is rendered. That may include incision for
drainage, canal debridement, opening the tooth, prescribing appropriate
medications, or doing whatever is necessary to resolve the problem.

10. MEASUREMENT
Ø Pain is a subjective perception that is difficult to quantify let
alone compare between different individuals and as such is a
problematic marker for detecting flare-up.
Ø In an effort to quantify and measure pain, the visual analogue
scale (VAS) has been proposed by Seymour et al.
Ø This is a mathematical progression from 0 to 100, 0 being no
pain and 100 being the most severe pain imaginable.

11. A flare-up is defined as an
increase of 20 or more points on
the VAS for a given tooth, within
the periods of 4 h and 24 h
after the initial treatment
appointment.
Ernest H. Ehrmann,Harold H. Messer, Robert M. Clark,
Aust Endod J 2007; 33: 119–130

12. ‘Flare-up Index’ by RIMMER
q This extends from 0 to 45 and encompasses nine variables. These
include not only different degrees of pain but also swelling and trismus.
q This index has not found acceptance as it is altogether too complicated.
q Flare up index attempts to show the effectiveness of the treatment or
infectiveness of the treatment.

13. Questionnaire For range
Existence of pain after the first visit 0 - 1
No of days with pain X pain degree / day 0 - 21
How many days were analgesic taken? 0 - 7
How many times emergency treatment was needed? 0 - 7
Does pain still exist in what degree? 0 - 3
Are Analgesic still being taken? 0 - 1
Did Swelling appear and what degree? 0 - 3
Existence of limitation of mouth opening 0 - 1
Systemic involvement (temp, fatigue) 0 - 1
TOTAL 0-45

14. INCIDENCE
• The overall incidence of flare-
ups is low.
• Ranges from 1.5% to 5.5%
• Increases in direct relationship
to the severity of the patient’s
pre-operative pathosis
and signs/symptoms.
Pulp necrosis and
acute apical abscess.
Present with more
severe pain and
swelling
Vital pulp without
periapical pathosis.
Walton R, Fouad A. Endodontic interappointment flare- ups. a prospective
study of incidence and related factors. J Endod 1992: 18: 172–177.

15. Author Result
Morse reported (1987) 2.2%
Walton reported (1992) 3.17%
Mura reported (1995) 1.58%
Kakahura reported ( 2001) 1.23%
Pickenpaugh (2001) 1.58%-9%

16. Risk Factors For Developing A Flare- Up
1. Patient Related (Demographic)
2. Pulpal/Periapical Diagnosis
3. Presenting Signs And Symptoms
4. Treatment Procedures.

17. WHY?
UG student patients experienced
fewer flare ups than faculty or
PG. WHY? Discuss.
Walton R, Fouad A. Endodontic Interappointment flareups.a prospective study
of incidence and related factors. J Endod 1992: 18: 172–177.

18. Risk Factors For Developing A Post
Endodontic Flare-up
Patient Factors
• Age/Gender
• Pulpal Necrosis
• Acute Apical Abscess
• Large Periapical Radiolucency
• Acute Apical Periodontitis

19. Age
Age does not seem to be a significant factor.
Several investigations have failed to find any evidence indicating that age is a risk factor
for development of flare-ups.
Imura N, Zuolo M. Factors associated with endodontic flare-ups: a prospective study. Int
EndodJ1995: 28: 261–265.
Walton R, Fouad A. Endodontic Interappointment flareups.a prospective study of incidence
and related factors. JEndod1992: 18: 172–177.

20. Patients in the age group of 40-59 years had the most
flare ups and those under the age of 20 had the least.
Torabinejad M, Kettering J, McGraw J, Cummings R,Dwyer T, Tobias T. Factors
associated with endodontic interappointment emergencies of teeth with necrotic
pulps.J Endod 1988: 14: 261–266.

21. Gender
Several studies found
higher numbers of
post-treatment pain
and flare-ups in
females.
Genet J, Hart A, Wesselink P, Thoden Van Velzen S. Preoperative and operative factors
associated with pain after the first endodontic visit. Int Endod J 1987: 20: 53–64.
Torabinejad M, Kettering J, McGraw J, Cummings R,Dwyer T, Tobias T. Factors associated
with endodontic interappointment emergencies of teeth with necrotic pulps.J Endod 1988: 14:
261–266.

22. Mor C et al suggested that the
incidence of inter-appointment
emergency associated with
endodontic therapy was 4.2%
and unrelated to patients
sex , age or the tooth
location .
Mor C, Rotstein I, Friedman S.Incidence of interappointment emergency
associated with endodontic therapy.J Endod ;18:10,1992 509-511

23. Systemic Conditions
This aspect has been largely
uninvestigated.
A study reported that allergies were
significantly related to flare-ups.
Although this could not be replicated in
another study BY WALTON.
Torabinejad M, Kettering J, McGraw J, Cummings R,Dwyer T, Tobias T. Factors
associated with endodontic interappointment emergencies of teeth with necrotic
pulps.J Endod 1988: 14: 261–266.

24. Pulp and Periapical Status
It is generally accepted that the flare-up rate after the extirpation
of a vital pulp is either non-existent or very low, even if the pulps
were painful before instrumentation.
Negm et al
Vital Pulp Few Flare-ups
Pulpal Necrosis Higher Incidence Of Flare-ups.

25. RICHARD E. WALTON
Interappointment flare-ups:incidence, related factors,prevention, and management
ENDODONTIC TOPICS 2002.1601-1538
As the severity of pulp pathosis increases, patients are more likely to
experience a flare-up.

26. RICHARD E. WALTON
Interappointment flare-ups:incidence, related factors,prevention, and
management
ENDODONTIC TOPICS 2002.1601-1538

28. The periapical diagnosis of acute apical
abscess and acute apical periodontitis, both
painful entities, have been shown in most studies
to also result in a significantly higher flare-up
rate
In addition, the radiographic presence of a
periapical lesion, particularly larger lesions,
also serves as a risk factor for development of
flare-ups.
>16-22mm

29. Factors Related To A Reduced Risk For
Developing A Post-endodontic Flare-up
Patient factors Treatment factor
Vital Pulp Obturation
Sinus Tract

30. SINUS TRACT
Interestingly, the presence of
a sinus tract virtually ensures
that a flare-up will not
occur.
The tract functions as a RELIEF VALVE ~
releasing pressure - reducing tissue levels of
inflammatory mediators - preventing the sudden
increase in pain.

31. Treatment Plan
• Whether the case involves
conventional vs. re-treatment
• If the dentist chooses single or
multiple visits
• Performs partial vs. complete
debridement
• Treatment procedure

32. 1. Rotary motion seems to negatively impact the postoperative pain after root canal treatment.
2. Overall, rotary motion causes more cases of postoperative pain, regardless of pain intensity
and time.
3. Reciprocating motion has been demonstrated to bring about lesser bacterial extrusion
compared to multifile rotary systems and consequently, there is a minor frequency of pain.
4. The association of debris extrusion and increase of bacterial colonies in the conventional
multi-file rotary system is greater when compared to the reciprocating single-file
instrumentation.

33. The available evidence indicated that maintaining AP
(1) Did not increase postoperative pain in teeth with nonvital pulp
(2) Did not increase postoperative pain in teeth with vital pulp
(3) Did not cause (0%) flare-ups
(4) Maintaining AP did not increase analgesic use
(5) Did not increase postoperative pain when a single-visit or 2-visit root
canal treatment approach was used
JOE — Volume -, Number -, - 2018

34. Re-treatment
• There is no universal agreement as to whether
retreatment results in a higher incidence of
post-treatment pain or more flare-ups than
conventional root canal treatment
• Most studies indicate that there is no
difference.
Mor C, Rotstein J Endod 1992: 18: 509–511.
Mattscheck D, Law A, Noblett W. Retreatment versus initial root canal
treatment: factors affecting post-treatmentpain. Oral Surg Oral Med Oral Path
Oral Radiol Endod 2001: 92: 321–324.

35. Study found high
incidence of flare up
in retreatment cases
13.6%
Trope . IEJ 1991.

36. Number of Visits
There is no consistency in the literature; some studies show
numbers of visits to be a factor.
Whereas others show no difference , when combining and
considering all diagnoses, signs and symptoms.
Imura N, Zuolo M. Factors associated with endodontic flare-ups: a prospective
study. Int Endod J 1995: 28: 261–265.
Eleazer P, Eleazer K. Flare-up rate in pulpally necrotic molars in one-visit versus
two-visit endodontic treatment. J Endod 1998: 24: 614–616.

37. Compelling evidence
indicating a significantly
different prevalence of
postoperative pain/ flare-up
of either single- or multiple-
visit root canal treatment is
lacking.
Sathorn C, Parashos P, Messer H. The prevalence of postoperative pain and
flare-up in single- and multiple-visit endodontic treatment: a systematic review.
International Endodontic Journal, 41, 91–99, 2008.

38. Majority of endodontists have found that single visit endodontics
does not cause more flare-ups than multi - visit treatments.
Based on clinical and scientific principles, the practitioner must
decide if root canal treatment is to be completed in one or more
appointments according to each specific case.

39. Ø Teeth without apical periodontitis did not flare-up
and may be treated in a single visit
Ø Teeth with apical periodontitis but no previous
root treatment can be treated in a single visit,
with a low probability of a flare-up occurring
Ø Teeth with apical periodontitis which need
retreatment, the flare-up rate was highest and
single-visit root treatment would be inadvisable
M. TROPE

40. Debridement
Incomplete debridement has been
traditionally assumed to be a cause
of flare-ups.
However, studies have shown this
factor to be unrelated to the risk
of developing a flare-up
Balaban F, Skidmore A, Griffin J. Acute exacerbations followinginitial treatment
of necrotic pulps. J Endod 1984:10: 78–81.

41. POLL TIME
1. How many of you feel that prophylactic antibiotics cause
reduction in the development of inter appointment flair up?
• Yes: OF Course. Prophylactic antibiotics should be given
routinely.
• Nope: It has no effect on the development of pain.
• I don’t know: You tell me, you’re taking this seminar.

42. Therapeutics
Studies showed prophylactic
antibiotics to be unrelated to
flare-ups .
Another study reported that
patients taking antibiotics
were more likely to have a
flare-up than those that were
not. Pickenpaugh L,Reader A,BeckM,Meyers W,PetersonL.Effectofprophylactic amoxicillinon
endodontic flare-upinasymptomatic,necrotic teeth.J Endod2001: 27: 53–56.
WaltonR, Chiappenelli J.Prophylactic penicillin; effectonposttreatmentsymptoms followingroot
canal treatmentofasymptomatic periapical pathosis.JEndod1993: 19: 466–470.

43. The outcome showed that prednisolone resulted in a statistically significant
reduction in post endodontic pain at 6, 12, and 24 hours.
30mg/30
mins before
the
procedure.

44. Analgesics
1. There is good evidence that pre-treatment analgesics minimize
inter and post treatment pain .
2. Pre-treatment pain and anxiety control may reduce incidence of
flare-ups

45. CAUSATIVE FACTORS
Chemical
Microbial
Mechanical

46. Mechanical Injury
1. Inadequate Debridement
2. Over Instrumentation
3. Periapical Extrusion Of Debris
4. Incorrectly Measured Working
Length

47. Irrigating Solutions
Intracanal Medicaments
Over Extended Root Fillings
Chemical Injury

48. ETIOLOGY
1. Alteration Of The Local Adaptation Syndrome
2. Changes In Periapical Tissue Pressure
3. Microbial Factors
4. Effects Of Chemical Mediators
5. Changes In Cyclic Nucleotides
6. Immunological Phenomena
7. Various Psychological Factors
SELTZER .NAIDORF.FLARE UPS IN
ENDODONTICS:ETIOLOGIC FACTORS.JOE 2004

49. 1. Local Adaptation Syndrome
ü Selye - there is a local tissue adaptation to applied irritants.
ü Ordinarily, the C.T become inflamed when they are exposed to an irritant.
ü Chronic inflammation persists if the irritant is not removed; there is local
adaptation.
ü When a new irritant is introduced to inflamed tissue, a violent reaction
may occur.

50. AIR INJECTED SC AIR POUCH FORMATION

52. The inflammatory lesion may be adapted to
the irritant, and chronic inflammation may
exist without perceptible pain or swelling.
When endodontic therapy is performed, new
irritants in the form of medicaments,
irrigating solutions, or chemically altered
tissue proteins may be introduced into the
granulomatous lesion.
A violent reaction may follow, leading to
liquefaction necrosis, indicative of an
alteration of the local adaptation syndrome.

53. 2. Changes In Periapical Tissue Pressure
Ø Various pathological conditions usually
produce a wide range of positive pressures.
Ø The experiments of Mohom et al have
indicated that endodontic therapy may also
cause a change in the periapical tissue
pressure.

54. Bacterial, chemical and physical irritants likely act in combination to produce changes at the periapex
that result in inflammation and ultimately pain and/or swelling.

55. Periapical Pressure >Atmospheric Pressure
Excessive Exudate
Not Resorbed By The
Lymphatics
Pain By Pressure On
Nerve Endings.

56. PERIAPICAL PRESSURE < ATMOSPHERIC PRESSURE
Microorganisms and
altered tissue proteins
Aspirated into the
periapical area in
accentuation of the
inflammatory
response
SEVERE PAIN

57. 3. Microbial Factors
1. Presence of pathogenic
bacteria
2. Presence of virulent
clonal types
3. Microbial synergism or
additism
4. Number of microbial cells
5. Environmental causes
6. Host resistance
7. Herpes virus infection
Microbial injury caused by microorganisms and their products that egress from the root canal
system to the periradicular tissue is conceivably the major and most common cause of
interappointment flare ups.
Development of pain precipitated by infectious agents can be
dependent on several factors, most of which are likely to be
interconnected

58. Presence Of Pathogenic Bacteria
q Bacteriodes, Fusobacteria and Peptostreptococci are the
most frequent anaerobic isolates in flare – up.
q F. nucleatum is associated with the development of most
severe forms of inter appointment endodontic flare ups
q B. melanogenicus acts synergistically with other obligate
anaerobes and facultative anaerobes.
Bacteria Flare Up

59. F. nucleatum appears to be
associated with the
development of the most
severe forms of
interappointment
endodontic flare-ups.

61. Presence of Virulent Clonal Types
§ Clonal types of a given pathogenic bacterial species can significantly
diverge in their virulence ability.
§ A disease ascribed to a given pathogenic species is in fact caused by
specific virulent clonal types of that species.
§ Presence of virulent clones of candidate endodontic pathogens in the
root canal may be a predisposing factor for interappointment pain,
provided that conditions are created for them to exert pathogenicity.

62. Microbial Synergism
Most of the presumed endodontic pathogens
only show virulence or are more virulent when
in association with other species.
Aerobes use O2 and liberate CO2
Anaerobes use CO2 and survive and exert
virulence
Prevent complete colonization by aerobes
Number Of Microbial Cells
If the host is faced with a higher number
of microbial cells than it is used to
dealing with, acute exacerbation of the
peri-radicular lesion can occur.
This can be accidentally precipitated by
endodontic procedures (not necessarily
iatrogenic ones).

63. Environmental Causes
A great deal of evidence indicates that the environment exerts an important role in inducing
the turning on or the turning off of microbial virulence genes.
Studies have demonstrated that environmental changes can influence the behaviour of some
putative oral (and endodontic) pathogens, including P. gingivalis, F. nucleatum, P. intermedia,
and oral treponemes.
If the root canal environmental conditions are in someway altered by intracanal procedures
and as a result become conducive to the expression of virulence genes, microbial virulence
can be enhanced and interappointment pain can ensue.

64. Host Resistance
Different individuals present different
patterns of resistance to infections,
and such differences can certainly
become evident during individual‘s
lifetime.
Individuals who had reduced ability
to cope with infections may be
more prone to develop clinical
symptoms after endodontic
procedures in infected root canals.

65. Herpes Virus Infection
1. Herpesviruses ~ interfere with the host immune response ~
trigger overgrowth of pathogenic bacteria and/or diminish the
host resistance to infection.
2. Induce the release of proinflammatory cytokines by host
defense cells.
A recent study observed that active infections of periradicular
lesions by human CMV and/or EBV were significantly associated
with symptomatology.
Thus, the possibility exists that active herpesvirus infections in
periradicular lesions may initiate or contribute to flare-ups.

66. Circumstances In Which Micro-
organisms Can Cause Flare-ups
During BMP, if the microorganisms are apically
extruded, the host will face a situation in which it
will be challenged by a larger number of irritants
than it was before.
Consequently, there will be a transient disruption in
the balance between aggression and defence in such
a way that the host will mobilize an acute
inflammation to re-establish the equilibrium.
v Apical Extrusion Of Infected Debris

67. v Iatrogenic Over Instrumentation
ü Promotes the enlargement of the apical foramen.
ü Permits the increased influx of exudates and blood into the
root canal.
ü Enhances the nutrient supply to the remaining bacteria within
the root canal that can then proliferate and cause
exacerbation of a chronic periradicular lesion.
Chavez de Paz Villanueva 2002

68. Also can cause
mechanical injury to
the periradicular
tissue which is
usually coupled with
the apical extrusion
of significant debris.
Forcing
microorganisms and
their products into
peri-radicular tissues
can generate
inflammatory
response whose
intensity will depend
on the number and
virulence of micro
organisms.

69. 1. All instrumentation techniques have been
shown to promote apical extrusion of debris
2. Crown down techniques usually extrude less
debris and should be elected for
instrumentation of root canals.
DUMMER AND FAVIERI
Hence, Quantitative Factor is more
likely to be under the control of the therapist.

70. Qualitative Factor is more difficult to control.
Virulent clonal types of pathogenic bacterial species
Propelled to the peri-radicular tissues
Even a small amount of infected debris
Potential to cause or exacerbate the peri-radicular inflammation

71. (SUNQUIST 1992).
Bacterial
organizations
within infected
root canals
associated with
periradicular
lesions.

72. Changes In The Endodontic Microbiata
Or In Environmental Conditions
1. The chemo-mechanical preparation should be completed in one appointment, and
between visits, an ICM should be left in the root canal.
2. Incomplete chemo-mechanical preparation can disrupt the balance within the
microbial community by eliminating some of the inhibitory species and leaving
behind other previously inhibited species, which can then overgrow.
3. If overgrown strains are virulent and / or reach sufficient numbers, damage to the
peri-radicular tissues can be intensified, and this may result in lesion exacerbation.
(SUNQUIST 1992).

73. Induce turn-off of virulence genes
Remission of the symptoms of
previously symptomatic cases could
ensue
Success of the endodontic
treatment even in situations where
microorganisms are not completely
eradicated from the root canal.
Induce turn-on virulence genes,
A previously asymptomatic case may become
symptomatic or
A persistent infection can establish itself in the root
canal system.
Persistent infections may be difficult to eradicate,
and they are main cause of treatment failure
Environmental Changes
Because it is clinically impossible to predict whether
environmental changes will lead to turn-on or turn-off
of virulence genes, BMP should be completed in one
session, whenever it is possible.

74. Secondary Intra-radicular Infections
Introduction of new microorganisms into the root canal system
during treatment usually occurs following a breach of aseptic chain.
Ø Remnants Of Dental Plaque
Ø Calculus/Caries On The Tooth Crown
Ø Leaking Rubber Dam
Ø Contaminated Endodontic Instruments
Ø Leaking Temporary Restoration

75. Microorganisms can enter in between appointments,
after
1. Leakage through the temporary restorative
material
2. Breakdown of fracture or loss of the temporary
restoration
3. Fracture of tooth structure
4. Recurrent decay exposing the root canal filling
material
5. Delay in the placement of permanent restorations

76. BEST DOUBLE SEAL?

77. POLL TIME
1. What’s your opinion on an open dressing in endodontics?
• Closed Dressing is given. Period.
• Closed most of the time: Only in severe case, Open for a day or
two followed by closed dressing.
• Open dressing after an acute episode for drainage, then closed.

78. https://www.researchgate.net/post/In_case_of_apical_swelling_with_pus_How_many_
days_should_we_keep_open_the_canal_to_discharge_the_pus

79. Exposure of the root canal to salivary
products logarithmically
ü Increases bacterial growth
ü Introduces new microorganisms
ü Activates the alternate complement
pathway
ü May enhance bradykinin production

80. EXCEPTION HOWEVER EXISTS: Cases of
uncontrolled massive exudation: Weine -
“If the drainage refuses to stop or if there is not time or
space to allow for drainage, the tooth may be left open
and the patient dismissed. The tooth may be reclosed,
without filing, when all symptoms have disappeared,
usually in 2-3 days”

81. 1936 Alfred Walker: “This method is an unscientific as
it is antiquated. The practice of leaving the pulp canals
of teeth open and unsealed for the purpose of drainage
is contrary to the accepted surgical practice, is
unnecessary and is a consequence of a bad practice”.
1975, 1982 Weine et al: “Establishment of drainage
followed by complete chemo-mechanical
preparation, placement of an antimicrobial
preparation, and coronal closure at the same
appointment result in reduced risk of persistent
symptoms as well as in fewer appointments to
complete the therapy when compared with teeth
left open for drainage”
2003 J. F. Siqueira: “If no pus drains through the
root canal even after apical trephination, it will not
do even if the tooth is left open for many days”

82. Ø Theoretically there may be more oxygen in a tooth left open and therefore
fewer anaerobic bacteria, which may be easier to eliminate, however, there may
be introduction of bacteria such as E. faecalis, which are more difficult to
eliminate.
Ø The recommendation is to avoid practices that introduce microorganisms into
root canal systems. The available evidence does not show benefit from the practice of
open drainage.
Ø The current quality guidelines for non- surgical endodontics do not
include open drainage as a treatment modality and the aim of
treatment is stated as ‘either to maintain asepsis of the root canal
system or to disinfect it adequately’.
European Society of Endodontology. Quality guidelines for endodontic treatment:
consensus report of the European Society of Endodontology.
Int Endod J 2006; 39: 921–930.

83. Increase of the oxidation-reduction
potential
• When tooth is opened O2 penetrates into root canal system and
microbial growth pattern changes from anaerobic aerobic
conditions.
• If facultative anaerobes such as streptococci are present in root
canal infection and resist intra canal procedures, they may
overgrow as a result of increase in the redox potential and ignite
acute peri-radicular infection.
MATUSOW

84. Entrance of oxygen into the root canal
during treatment may favour the
overgrowth of facultative bacteria that
resisted chemomechanical procedures.
This mechanism is only conjectural,
and there is no clear evidence
substantiating this theory.

85. 4. EFFECTS OF CHEMICAL MEDIATORS
During the inflammatory response, chemicals can be derived from cells or plasma.
Cell Mediators
• Histamine
• Serotonin (5-hydroxytryptamine (5-HT)
• Prostaglandins (PGs)
• Platelet-activating factor (PAF)
• Leukotrienes (LT)
• Various lysosomal components
• And some lymphocyte products called lymphokines

86. Plasma Mediators
v Plasmin
v Fibrinopeptides And Fibrin Degradation
Products
v Bradykinin
v Pre-kallikrein Activator
v Hageman Factor
Highly potent pain inducer

87. Neutrophil Products
v Hydrolytic enzymes
v Lysozyme
v Collagenases
v Cathepsins
v F3-glucuronidase
v Peroxidase
v Amylases
v Lipases
v Ribonucleases
v Deoxyribonucleases
v Lactic dehydrogenases.
The release of those enzymes produces damage to nearby
cells and other tissue elements. Severe pain and swelling
may result.

88. 5. CHANGES IN CYCLIC NUCLEOTIDES
ü According to the hypothesis of Bourne et al, the character and intensity of
inflammatory and immune responses is regulated by certain hormones and
mediators.
ü This regulation is mediated by a general inhibitory action of cyclic AMP on the
release of mediators from mast cells. basophils, monocytes, and polys.
ü Increased intracellular levels of cyclic AMP, induced by PGs and histamine, may
inhibit degranulation of mast cells and help in reducing pain.
ü Where as an increase in cyclic GMP stimulates mast cell degranulation which results
in increase in pain.

89. cAMP
cGMP

90. 6. IMMUNOLOGICAL PHENOMENA
1. In chronic pulpitis and apical periodontitis, the presence of macrophages
and lymphocytes indicates that both cell-mediated and humoral immune
reactions are involved.
2. Despite their protective effects, immunological mechanisms may
contribute to the destructive phase of inflammation.
3. The type of clinical response may be dictated by the type of
immunoglobulin elaborated.

91. Ø Should the dominant immunoglobulin in the pulp or periapical lesion be lgG,
there is a possibility of an Arthus-type reaction, after complement activation,
owing to the local formation of immune complexes.
Ø On the other hand, if the dominant immunoglobulin is IgA, complement-fixing
activity is low.
<
Pain and destruction
are the result of a shift
in the production of
lgG over IgA, causing
perpetuation and
aggravation of the
inflammatory process.

92. 7. PSYCHOLOGICAL FACTORS
q Fear of dentists and dental procedures,
anxiety, apprehension, and many other
psychological factors influence the patient‘s
pain perception and reaction thresholds.
q Previous traumatic dental experiences
appear to be significant factors in the
production of anxiety and apprehension in
dental patients.

93. • Root canal therapy, especially, appears to be
painful to many patients either because of
antecedent experiences or from conversations
with others or from derogatory comments
made by communications media.
• The induced anxieties help to intensify and
perpetuate painful episodes.
“Nothing
personal, but I
HATE
dentists.”
“I can stand
PAIN
anywhere but
in the mouth.”“I‟d rather
HAVE A
BABY than
be here.”

94. CLINICAL
CONDITIONS
ASSOCIATED
WITH FLARE
UPS

95. Apical Periodontitis Secondary To
Treatment
1. A tooth which was symptomless before
the initiation of endodontic treatment
but becomes sensitive to percussion
during the course of the treatment.
2. Causes for this condition most frequently
are over instrumentation or forcing
debris into the periapical tissues.

96. Incomplete Removal Of Pulp
Tissues During The Initial
Appointment
1. In some instances due to lack of time factor the
endodontic therapy may consist of incomplete
pulpectomy after a diagnosis of acute or
chronic pulpitis.
2. This situation generally occurs when the
radicular pulp is already inflamed.

97. Phoenix Abscess
1. It is a condition that occurs in teeth with
necrotic pulps and apical lesions that are
asymptomatic .
2. There is a exacerbation of a previously
symptomless peri-radicular lesion.
3. The reason for this phenomenon is thought to
be due to the alteration of the internal
environment of the root canal space during
instrumentation which activates the bacterial
flora .

98. Recurrent Periapical Abscess
1. It is a condition where a tooth with an
acute periapical abscess is relieved by
emergency treatment after which the acute
symptoms return.
2. In some cases the abscess may recur more
than once, due to micro organism of high
virulence or poor host resistance.

99. Microbial Mechanism Preventive Measures
1. Apical extrusion of infected debris
• Crown down instrumentation technique
• Rotary<Reciprocation instrumentation
• Coronal flare
• Copious and frequent irrigation
2. Changes in environmental conditions
• Complete cleaning and shaping in one sitting
• ICM
3. Secondary intra radicular infection
• Strict aseptic measures
• Proper coronal seal
• Do not leave tooth open for drainage
4. Increase of oxidation reduction
potential
• Complete BMP in one sitting
• ICM

100. PREVENTIVE
MEASURES

101. Relief of Occlusion
¢ Occlusal relief prior to endodontics has
been advocated by Cohen for the
prevention of endodontic pain.
¢ Other endodontists (Olgivle AL,
Ingle, Nichols E.) have recommended
occlusal relief only in those teeth with
pre-operative acute apical symptoms.

102. 1. Since microorganisms are responsible for exacerbating
inflammation, it would appear that the intracanal placement of
root canal antiseptics and germicides should at least indirectly
reduce inter and post treatment pain.
2. According to Seltzer, intracanal medication reduces the
possibility of flare ups.
Intracanal Antimicrobial Agents

103. 1. The use of intracanal steroids (NSAIDs) or a
corticosteroid– antibiotic compound has been
shown to reduce post-treatment pain.
2. Rogers et al. demonstrated that both
dexamethasone and ketorolac when placed in the
root canals of vital teeth after pulpectomy
procedures showed statistically significant pain
relief at the 12-h time period as compared to the
placebo group. No adverse reactions were found
following their placement within the root canal
system.
J Endod 1999;25:381–389.,Oral Surg Oral Med Oral Pathol Oral Radiol
Endod 2001;92:435–439.

104. 1. Compare the effect of ledermix paste and calcium hydroxide as
intracanal medicament on the mean postoperative pain after
instrumentation of the root canals.
2. Calcium hydroxide was found inferior to ledermix treatment in
controlling the postoperative pain after instrumentation of the root
canals.
Pak Armed Forces Med J 2020; 70 (2): 368-72

105. LEDERMIX PASTE
Medicinal active substance : 1g of paste contains:
Triamcinolone acetonide 10.0 mg
Demeclocycline calcium 30.21 mg
Rs. 9500
Medicinal inactive substance
Triethanolamine, Calcium chloride, Zinc Oxide, Macrogol 3000, Macrogol
400, Sodium Sulphite Anhydrous, Sodium Calcium Edetate, Colloidal Silicon
Dioxide
Purified water
At the first 24 hours, 30% of the
corticosteroid was released.
By the end of 14 weeks, the
remaining 70% has been released.
Mixing erythromycin with
Ca(OH)2 improved the
effectiveness against E. faecalis as
compared to Ca(OH)2 alone.

106. Irrigating Solutions
Harrison et al. found that there was a
higher incidence and degree of pain in
patients whose canals were either not
irrigated or irrigated with saline solution,
compared with those irrigated with
5.25% sodium hypochlorite and 3% H2O2.

107. Corticosteriods
1. The anti-inflammatory activity of corticosteroids is based partly
on their ability to retard lysosomal release from cells by
inhibiting fusion of lysosomes with their target membranes.
2. In addition, corticosteroids inhibit the liberation of free
arachidonic acid from the phospholipids of the cell membrane
by phospholipases.

108. A number of investigators have reported that corticosteroids placed into
the root canal control pain successfully.
Langeland K, Langeland LK, Anderson DM. Corticosteroids in dentistry.Int Dent J 1977;27:217.
Moskow A, Morse DR, Krasner P, Furst ML. Intracanal use of a corticosteroid solution as an endodontic anodyne. Oral Surg 1984;58:600.
There is no demonstrated benefit in placing medicaments or any other
substance in canals to help prevent or resolve a flare-up.
Richard E. Walton, Endodontic Topics 2002
Steroids, administered in a single dose (e.g. 4–6mg of dexamethasone) may
also be of benefit to reduce pain.
Leisinger A, Marshall FJ, Marshall JG. Effect of variabledoses of dexamethasone on post treatment endodontic pain. J Endod 1993: 19: 35–39.

109. Antibiotics
1. Although antibiotics are widely used in treating a localized abscess, prospective
clinical trials show they are of no benefit for reducing postoperative pain or risk of
developing a flare-up.
2. There are no significant studies which show that any specific antibiotic is capable of
reducing or eliminating painful exacerbations during endodontic therapy.
3. In a review on the use of systemic antibiotics for the control of post-treatment
endodontic pain, Fouad concluded that their use is without justification.

110. 1. However, it appears that antibiotics are frequently prescribed to
the endodontic pain patient.
2. Current advances in our understanding of the biology of the
infectious and inflammatory process, along with the known risks
associated with antibiotics, such as the emergence of multi-
resistant bacterial strains, strongly indicate that the clinician
should seriously re-evaluate their prescribing habits.

111. Analgesics
There is good evidence that
pretreatment analgesics minimize
inter and post treatment pain.
Dionne R. Preemptive vs. preventive analgesia: which approach
improves clinical outcomes? Compend Contin Educ Dent 2000: 21:
51–456.
Gottschalk A, Smith DS. New concepts in acute pain
therapy:preemptive analgesia. AmFamPhysician 2001: 63:1979–
1984.
Pretreatment pain and anxiety
control, including analgesics,
may reduce incidence of flare-
ups
TorabinejadM,CymermanJ,FranksonM,LemonR,MaggioJ,
Schilder H.Effectiveness ofvarious medications onpostoperative
painfollowingcompleteinstrumentation.JEndod1994: 20: 345–354.

112. Post Treatment Patient Care: Cohen*
Ibuprofen 200mg X 3
Acetaminophen 500mg X 2
5
Every 6 hours X 2 days
*No Allergies for an average 72kg man
Rx

113. MANAGEMENT
OF
FLARE UPS

114. Although some patients may
experience some level of pain after
RCT, very few experience the true
‘flare-up’, which requires an
unscheduled office visit and/or the
prescribing of analgesics, systemic
steroids and antibiotics.
Post-treatment Pain

115. Hargreaves and Seltzer: Pain Control
Diagnosis
Definitive
Rx
Drugs
Psychological
Localized Treatment

116. DIAGNOSIS
ü Patient medical and dental history
ü Clinical testing- percussion, apical palpation, bite-stick challenge, thermal stimulation and
periodontal probing.
ü Areas of swelling, discoloration, ulcerations, exudation, defective and/or lost restorations,
cracked or fractured teeth and apparent changes in occlusal relationships.
Unrelated
Sinus
Another
Tooth
TMJ Related
Condition
Post Injection
Sequalae
Odontogenic
Non-
Odontogenic

117. The big
REASSURANCE
is critical & perhaps the most
important aspect of treatment.

118. MANAGEMENT STRATEGIES
1. Apical Trephination
2. Incision And Drainage
3. Cortical Trephination
a. - With Drain
b. - Without Drain
4. Antibiotic(?) Regimen With NSAIDs
5. Hot Saline Holds To Localize Diffuse Swelling
6. Culture And Sensitivity Testing

119. Re-instrumentation
Adequate Anesthesia
Access Opening
Re-confirm WL
Patency To Apical Foramen
Thorough Debridement With Copious Irrigation

120. 1. Weine advocated ‘violating’ and enlarging the apical constriction
to at least a size #25 endodontic file to allow for drainage
through the tooth.
2. Nonetheless, Harrington and Natkin stated that trephination
through the apical foramen does not ensure drainage of peri-
radicular exudation.
Apical Trephination

121. Hot Saline Holds For Diffuse Swellings
- Localized heat (hot saline water) tends to draw pus to the tissue surface (localizes the
swelling) so that I & D can be performed
- 1 teaspoonful of salt in hot water (as hot as is tolerable by intraoral tissues) in a glass ~
300 ml
- Hold the water in contact with tissues till it cools
- Use the entire glass and repeat every 4-8 hours.
- Advice patient against applying heat to face may localize swelling over face &
subsequent scaring.

122. Localized Treatment
ESTABLISHMENT OF DRAINAGE
1. In the presence of suppuration, drainage of exudate is the most effective method for
reducing pain and swelling.
2. In most instances, the accumulated exudate will surge from the root canal, affording
immediate relief.
3. However, upon occasion, no exudate will emerge; it may be blocked by packed
dentinal shavings in the apical third of the root canal.

123. 1. After adequate anaesthsia passing a
root canal instrument, such as a file or
reamer, through the caked material
may help to establish the flow of
exudate.
2. During drainage canal is left open for
about 15 mins or until exudation has
ceased or a slight clear serum drains.
3. After adequate drainage and irrigation
the root canal can then be resealed,
usually without further discomfort to
the patient.

124. The use of drains following an I & D procedure is controversial.
McDonald and Hovland have stated that the incision alone will usually provide the
needed drainage.
Frank et al. recommended the use of a rubber drain to maintain the patency of the
surgical opening.
Rubber Dam Drain
Penrose Drain
Caillary Drain-ribbed

125. 1. Gutmann and Harrison stated that the use of drains following I
& D procedures has been greatly abused.
2. Patients with localized or diffuse intraoral swellings ,even if mild
extra oral swelling is present, do not usually require drains
following I & D procedures.
3. The drain may be made of either iodoform gauze or rubber dam
material cut in an “H” or “Christmas tree” shape

126. A self-retentive
‘Christmas Tree’
drain made from
a sterilized rubber
dam
15 Blade

128. CORTICAL TREPHINATION
In exceptional cases, the exudate is either absent or cannot
be evacuated through the root canal.
Surgical intervention is then necessary.
The removal of the alveolar bone over the apex of the tooth
root (creation of an artifical sinus tract), or a soft tissue
incision when swelling has occurred usually affords relief.

129. PROCEDURE
1. Following the administration of the appropriate block and/or infiltration anesthesia, the
surgical area should be isolated with sterile 2 × 2 gauze sponges.
2. The incision should be horizontal and placed at the dependent base of the fluctuant area.
3. The incision should be made using a scalpel blade that is pointed, such as a No. 11 or No.
12, rather than a rounded No. 15 blade.
4. Gutmann and Harrison recommend using either a No.6 or No. 8 round bur in a high-speed
handpiece to penetrate the cortical plate.
5. A reamer or K-type file is then passed through the cancellous bone into the vicinity of the
periradicular tissues.

130. Probing with a curette or hemostat into the
incisional wound to release exudate entrapped
in tissue compartments will facilitate a more
effective result

131. 200$/Rs. 15,184
Endodontic
Spoon Excavator
Long
Shank

134. • Chestner et al. reported pain relief in patients with severe and recalcitrant peri-
radicular pain when cortical trephination was performed. Additionally, in the
asymptomatic patient, cortical trephination has been shown to decrease by 16–25%
post-operative pain incidence when performed prophylactically.
• Moos et al. compared the difference in post-operative pain relief in patients with acute
peri-radicular pain of pulpal origin when treated by either pulpectomy alone or
pulpectomy with cortical trephination. There were no significant differences between
the groups.

135. An apical trephination procedure did not significantly (p > 0.05) reduce pain, percussion pain,
swelling, or number of ibuprofen tablets taken in symptomatic necrotic teeth with periapical
radiolucencies.
The trephination procedure did significantly (p < 0.05) reduce the use of acetaminophen with
codeine overall for the 7 days.
In conclusion, because there was not a significant reduction in pain, percussion pain, or
swelling we cannot recommend the routine use of an apical trephination procedure, as used
in this study, in symptomatic necrotic teeth with radiolucencies.

136. PHARMACO-THERAPEUTICS
1. There is no specific analgesic that is preferentially
effective for the pain induced during root canal
therapy.
2. Avoid indiscriminate usage of opiod/steroidal
analgesics.
3. NSAIDs are shown to be effective in reducing pain in
most of the situations. For severe pain, a combination
approach (steroidal and nonsteroidal) is most
effective.

137. WHO Analgesic Ladder
• If pain is moderate to severe, opioid should be
employed along with the non-opioid analgesics,
but at this stage use a low potency opioid.
For ex: Codeine ,oxycodone, hydrocodone
is used first.
• If treatment pain is inadequate (or) patients
presents with severe pain, a high potency
opioid (morphine, hydro-morphine)
should be selected and prescribe along with
the non-opioid analgesics.

139. ANALGESIC TRADE NAME DOSE RANGE (MG)
DOSAGE/DAY
(MG)
Acetaminophen Crocin, Dolo 325-1000 4000
Aspirin Many 325-1000 4000
Diciofenac Potassium Cataflam 50-100 150-200
Etodolac Lodine 200-400 1200
Fenoprofen Nalfon 200 1200
Flurbiprofen Ansaid 50-100 200-300
Ibuprofen Brufen 200-400 2400
Ketoprofen Orudis 25-75 300
Ketorolac Ketorol DT 30-60 60

140. Anxiety Reducing Drugs (Sedatives)
• Diazepam ~ 5 mg oral
• Lorazepam ~ 0.25 mg oral
• Triazolam ~ 5 mg oral
Rs. 30
Rs. 8

141. Acupuncture
1. Used as an alternative therapy for relieving dental
pain, In the Geneva WHO 2003 report, pain in
dentistry, including dental pain, facial, and
postoperative pain, were listed among the conditions
for which acupuncture appears to be an effective
treatment.
2. Can be effective in relieving dental pain, either during
surgical procedures or after surgery.
3. Acupuncture was reported to be effective (at the
90%+ level) for the relief of "tooth- related pain.
Wong LB. acupuncture in dentistry: its possible role and application. Proc
Sing Healthc. 2012;21:48e56.
Postoperative endodontic pain was
reduced to tolerable levels within 15 to
20 min. This relief lasted indefinitely in
almost 50% of the cases.
LI 4 or Large Intestine 4
SI 18 or Small Intestine 18

142. Explanations and Instructions
Ø Detailed explanations of the procedures, the expected benefits, and the possible pain
responses help to allay the patients' anxiety and apprehension and reduce tension.
Ø Patients were more willing to endure pain if it was predicted.
Ø Specific instructions such as application of ice,
exact timing for ingestion of analgesics, and
possible alterations in the character of pain also
result in an elevation of pain threshold.
Ø An infrequent unexpected anxiety may be
induced by predictions of pain and swelling that
fail to materialize, but such anxieties can usually
be resolved by re-assurrances.

143. CULTURE SENSITIVITY
1. Amongst the various methods of self assessment and determining the exact choice of
ICM(organism specific) and selection of appropriate antibiotics, culturing is the most
reliable and trusted.
2. However, routine use of culturing can be quite tedious and expensive and may not
serve its exact purpose.
3. Researchers have shown that routine use of culturing in normal uncomplicated cases,
has no significant differences in flare up rates ad success rates.
4. Cases such as recurrent abscess cases and in patients who are immuno-compromized
warrant use of culturing and sensitivity testing.

144. TREATMENT
OF FLARE-
UPS IN
DIFFERENT
CLINICAL
SITUATIONS

145. Vital Pulp
Flare-ups seldom occur in these situations, but when
they do, the problem likely is related to tissue
remnants that have become inflamed.
Working lengths should be verified and the canals
carefully cleaned with copious irrigation
A dry cotton pellet is then placed followed by a
temporary restoration.
The pain will usually subside rather quickly and
predictably following administration of analgesics.

146. Previously Necrotic Pulp With No
Swelling
These teeth may develop a flare-up after the
appointment.
The abscess is confined to bone and is generally
very painful.
Management
Anaesthesia
Opening tooth
Drainage
Irrigation
Medicament
Resealing

147. Necrotic Pulps With Swelling
Localized swelling.
The tooth should be opened and
the canals re-debrided and
closed.
Incision and drainage.

148. Non Localized Swelling
Non-localized swellings, that is, rapidly
spreading into spaces, and those
patients with systemic signs of infection,
require antibiotics.
If the spread of infection is alarming,
extraoral drainage may be performed
and the patient may even be
hospitalized.

149. POST TREATMENT FLAREUPS
According to Seltzer nearly 1/3rd of
patients experience pain following
obturation
• Mild discomfort and tenderness
• Severe excruciating pain
• Pain with or without swelling

150. 1. Forces exerted during spreader penetration
~1.4kgf or more, plugger insertion.
2. Over heating and more than longer time of
contact of heated instrument tip with root canal
walls ~ > 10°C rise in temp.
3. Over filling and over extension
4. Over instrumentation
5. Missed canals
6. Sealer extrusion
7. Under obturation and instrumentation
8. Occlusal pre-maturities
9. Poor coronal seal
10. Other mishaps
>1.4
kgf

151. Management
1. Usually pain is mild and transient and managed with mild analgesics
2. Check occlusion
3. Take angled IOPAs
4. Reassure patients and recall patient in 1-2 days
5. Persistent pain and swelling
6. Remove fillings
7. I & D if swelling is fluctuant and has perforate through the cortex
8. Cortical trephination
9. Systemic medication
10. Periapical Surgery

152. Clinical
condition
Micro-
organisms
Intracanal medicament of choice Duration
Triple Antibiotic
paste
Regeneration
• Immature teeth with open apex
• Wide apical foramen
• Over instrumentation
• Inter appointment flare up in
diabetics
• Weeping canals
1 – 2 weeks
change the
dressing till the
lesion subsides
Ledermix paste
Micro organisms
of pulp &
periodontal
infection
• Over instrumentation
• Flare ups
• Replantation
• Traumatized tooth
• External inflammatory root
resorption
• Inflammatory periapical root
resorption
• Severe pain and tenderness on
percussion
For a week but
not more than 2
weeks

153. Intra canal
medicament
Micro-organisms Clinical condition Duration
Calcium
Hydroxide
Black-pigmented
bacteria,P.intermedia,
P.nigrescens, P. endodontalis,
P.gingivalis, F.nucleatum,
Veillonella, parvula,
Eubacterium & other species
• Primary infection A week
Calcium
Hydroxide with
chloxhexidine
Enterococci & streptococci
followed by lactobacilli,
Actinomyces species,
peptostreptococci, Candida,
Eubacterium alactolyticus,
Propionibacterium
propionicum
• Secondary or persistent
infection
• Sinus tract closure
For 7 days, till the
lesion heals

154. TAKE HOME MESSAGE
ü Proper diagnosis
ü Identify the correct tooth causing pain
ü Ascertain whether tooth is vital or non vital
ü Identify if tooth is associated with periapical lesion
ü Determine correct working length
ü Radiographs
ü Apex locators
ü Complete extirpation of vital pulp
ü Irrigation: NaOCl and CHX
ü Avoid filing too close to the radiographic apex
ü Preform apical trephination only if necessary
ü Reduce tooth from occlusion especially if apex is
severely violated by over instrumentation
ü Placement of ICM
ü Prescription of mild analgesics and antibiotics whenever
condition warrants it

155. SUMMARY
• Various Definitions
• Flare Up Criteria
• Measurement: VAS Scale/Rimmer’s
Index
• Incidence
• Risk Factors
• Etiology
• Theories of Flare Up
• Preventive Measures
• Definitive Management
• Clinical Situations in Flare Up

156. CONCLUSION
v Even though it has been demonstrated that a flare-up has no significant
influence on the outcome of endodontic treatment, its occurrence is
extremely undesirable for both patient and the clinician and can
undermine the clinician- patient relationships.
v Therefore, clinican should employ proper measure and follow
appropriate guidelines in an attempt to prevent the development of
inter-appointment sever pain and or swelling.

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158. THANK YOU!