International Journal of Dental and Health Sciences Review Article Volume 03,Issue 04

ENDODONTIC FLARE UP Amulya Vanti1, Hemant Vagarali2, Madhu Pujar3, Praven.S.Byakod4,Pallavi Gopishetti5, Supriya Malik6 1.PG student department of conservative and endodontic ,Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre 2.Associate proffessor department of conservative and endodontic Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre 3.Proffessor and HOD ,department of conservative and endodontic Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre 4.Proffessor ,department of conservative and endodontic Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre 5.Reader,department of conservative and endodontic Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre 6.PG student department of conservative and endodontic Maratha Mandal Nathajirao G Halgekar Institute of dental sciences and research centre

ABSTRACT: Pain management in is of utmost importance for clinician to prevent or manage undesirable conditions.Flare up is one of the complication in endodontic treatment.This review article covers the various incidence,causative factors,hypothetical mechanisms,prevention,different treatment modalities of endodontic flare ups. Keywords: Endodontic flare ups,irrigants,microorganisms

INTRODUCTION: International Association for the study highly related to the elimination or of pain defines pain as “unpleasant reduction of endodontic pain. sensory and emotional experience ENDODONTIC FLARE UP associated with actual or potential Defined as “Acute exacerbation of tissue damage”. Pain is the most asymptomatic pulp or periradicular common reason for dentist pathosis after the initiation or consultation. It is a major symptom in continuation of treatment”. many dental condition and can A flare up is characterized by severe significantly interfere with a person`s pain and swelling that may arise quality of life and general functioning following initial debridement of root .[18] It is often spoken as a protective canals or even after obturation. mechanism since it is usually Requiring an unscheduled visit by manifested when an environmental patients and active treatment. [6] change occurs that causes injury to According To American Association Of responsive tissue. In Endodontic, pain Endodontics, the inter - appointment may occur preoperatively, Inter flare ups has following criteria: appointment or postoperatively.[5] The Within few hours to a few days after success of Endodontic treatment is an endodontic procedure, a patient

*Corresponding Author Address: Dr Amulya Vanti Email: [email protected] Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 has significant increase in pain or  Older age : Flare up rarely swelling or combination of two. occur in older patients ,due to The problem is of such severity that the narrowing of the diameter of the patient initiates to contact with the root canal therefore less dentist. debris is extruded below the apex The dentist determines the problem is of the root . blood flow in the of such significance that the patient alveolar bone resulting in weaker must come for an unscheduled visit. inflammatory response.[8] At the visit active treatment is  Men : Less common among men rendered that may include incision for  Women : Pain threshold and drainage, canal debridement, opening toleration depend on sexual the tooth , prescribing appropriate hormones and their proportion medications or doing whatever is during different stages of necessary to resolve the problem.[7] menstrual cycle.Pain feeling is also INCIDENCE OF FLARE UP regulated by hormone cortisol  Over all incidence of flare- ups is which takes part in mechanisms ranges from 1.4% to 16% [1] that are responsible for  The incidence of flare-up processing the pain.Its amount increases in direct relationship to excreted in male amount is higher the severity of the patient’s than in females. [8] preoperative pathosis and GENERAL STATE OF HEALTH signs/symptoms. Flare up rate is low in patients using  Lowest frequency : vital pulp systemic steroids as treatment for without periapical pathosis systemic diseases. Steroids suppress Highest frequency : patients who the acute inflammatory response present with more severe pain during the chemo-mechanical and swelling, particularly with pulp preparation of the root canal when necrosis and acute apical abscess. mechanical, chemical and or microbial These more severe situations factors irritate the apical periodontal result in a flare-up incidence of tissue.8 Torabinejad et al points that close to 20%.[4,7] (Figure 1) patients tendency to allergies is As the severity of pulp pathosis associated with the development of a increases, patients are more likely to flare-up after endodontical treatment experience a flare-up ,however wolton and fouad study DEMOGRAPHICS disapproves this hypothesis. [6]  Younger age : Post operative pain CONDITION OF THE PULP AND APICAL was more among younger PERIODONTAL TISSUE patients (18-33 years old) according It is established that 47-60% of the to EIMubarak et al . patients having asymptomatic necrotic pulp experience pain defined from

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 medium to acute during the first 24 times more often when the canals hours after endodontic treatment. of the molar teeth are treated Bone destruction which is visible in compared to other teeth types. dental radiograph is said to be a risk  higher frequency of pain in teeth factor of flare-up . Chance of a flare is type is determined by the 9.64 times higher when the bone complicated complex anatomy of destruction is detected. the root canals and chemo The connection between size of the mechanical preparation.[8] bone destruction area and post- POSTOPERATIVE PAIN AND AMOUNT operative pain was defined by Gernet OF THE VISITS et al : bone destruction of 5mm and It is More common after one visit more is said to increase the endodontic treatment. Yold et al study probability of pain occurring.[8] (Figure summarizes that flare up rate is 4, 9 2) times higher after one visit PRESENCE OF A SINUS TRACT endodontic retreatment compared to  The presence of a sinus tract retreatment by two visits. [8,11,16,17] virtually ensures that a flare-up will INTRACANAL MEDICAMENTS not occur .  Studies show that there is no  Although this is indicative of an direct link between usage of abscess, apparently the tract intracanal medicaments between functions as a relief valve, releasing visits and frequency of the pain. pressure, reducing tissue levels of  Intracanal medicaments are inflammatory mediators, and ineffective in preventing the flare- thereby preventing the sudden up which is caused by extrusion increase in pain. [7] of infected debris through the CLINICAL SYMPTOMS apex of the root during the Clinical symptoms before the preparation of the root canal. [8] treatment such as tooth pain when ETIOLOGY OF FLARE UPS biting, chewing or by itself and MECHANICAL INJURY: sensitivity to percussion . 80% of  Over instrumentation patients who feel tooth pain before  Inadequate debridement or the beginning of the treatment incomplete removal of pulp tissue usually feel the pain after treatment.  Apical extrusion of debris Pain enhances the stress level in the  Secondary intraradicular infections body and effects immune function in CHEMICAL INJURY a negative way therefore increasing  Irritants the probability of a flare-up.[8]  Intracanal medicaments TOOTH WHICH IS BEING TREATED  Overextended filling materials  Glennon et al study results show that temporary pain is felt 1,7

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 But microbial injury is the major  Thus, presence of virulent clones and the most common cause of of candidate endodontic inter-appointment pain. pathogens in the root canal may These include be a predisposing factor for  Porphyromonas endodontalis interappointment pain, provided  that conditions are created for  Prevotella species them to exert pathogenicity.[13]  MICROBIAL SYNERGISM OR ADDITISM  (formerly Most of the presumed endodontic Bacteroides forsythus) pathogens only show virulence or are  Filifactor alocis more virulent when in association  Dialister pneumosintes with other species . This is because of  Peptostreptococcus micros synergic or additive microbial  Finegoldia (formerly interactions, which can certainly Peptostreptococcus) magna.1,13 influence virulence and play a role in (Figure 3) symptom causation .[13] PRESENCE OF PATHOGENIC BACTERIA NUMBER OF MICROBIAL CELLS  A recent study revealed that F. Host is faced with a higher number of nucleatum, Prevotella species and microbial cells than it is used to Porphyromonas species were dealing with, acute exacerbation of frequently isolated from microbiota the periradicular lesion can occur. This associated with flare-up cases. can be accidentally precipitated by  The possibility exists that the endodontic procedures (not bacterial species associated with necessarily iatrogenic ones) .[13] flare-ups are the same as those ENVIRONMENTAL CUES involved with primarily infected A virulent clone of a given pathogenic root canals associated with species does not always express its symptomatic periradicular lesions, virulence factors throughout its although it remains to be lifetime. confirmed. [13] A great deal of evidence indicates PRESENCE OF VIRULENT CLONAL TYPES that the environment exerts an  Clonal types of a given important role in inducing the turning pathogenic bacterial species can on or the turning off of microbial significantly diverge in their virulence genes . virulence ability. Studies have demonstrated that  A disease ascribed to a given environmental changes can influence pathogenic species is in fact the behavior of some oral (and caused by specific virulent clonal endodontic) pathogens, including P. types of that species. gingivalis, F. nucleatum, P. intermedia and oral treponemes . [13]

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 HOST RESISTANCE thought to be due to the alteration It is well known that different of the internal environment of the individuals present different patterns root canal space during of resistance to infections, And such instrumentation which activates the differences can certainly become bacterial flora.[5] evident during individual’s lifetime. RECURRENT PERIAPICAL ABSCESS Hypothetically, individuals who had It is a condition where a tooth with reduced ability to cope with Infections an acute periapical abscess is relieved may be more prone to develop by emergency treatment after which clinical symptoms after endodontic the acute symptoms return. In some procedures in infected root canals.[13] cases the abscess may recur more (Figure 4) than once,due to micro organism of HERPES VIRUS INFECTION high virulence or poor host resistance. Herpesviruses have the ability to MECHANISMS OF FLARE UPS interfere with the host immune Eight microbial and immunological response, which may trigger factors are seen to be responsible for overgrowth of pathogenic bacteria flare-ups (Seltzer et al 2004): and/or diminish the host resistance to 1. Alteration of local adaptation infection. syndrome Herpesviruses may induce the release 2. Changes in periapical tissue pressure of proinflammatory cytokines by host 3. Microbial Factors defense cells. A recent study observed 4. Effects of chemical mediators that active infections of periradicular 5. Cell mediators lesions by human cytomegalovirus 6. Changes in cyclic nucleotides and/or Epstein–Barr virus were 7. Immunological phenomenon significantly associated with symptoms. 8. Psychological factors [2,10] Thus, the possibility exists that active ALTERATION OF LOCAL ADAPTATION herpesvirus infections in periradicular SYNDROME lesions ,May initiate or contribute to Selye has documented that there is flare-ups. The mechanisms behind local tissue adaptation to chronic herpes viruses involvement with inflammation and a violent reaction symptomatic periradicular lesions occurs if a new irritant is introduced. remain elusive. He injected various irritating chemicals PHOENIX ABSCESS to subcutaneous air filled pouches of It is a condition that occurs in teeth a rat with necrotic pulps and apical lesions Formation of a granuloma pouch after that are asymptomatic . There is a sometime indicating chronic exacerbation of a previously inflammation. No reaction developed symptomless periradicular lesion. The when same irritant was used but a reason for this phenomenon is

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 severe flare up occurred when irritant in form of neutrophils products. Cell was changed. mediators include like histamine, APICAL EXTRUSION OF DEBRIS serotonin, prostaglandins, platelet In asymptomatic periradicular lesions activating factors, leukotrienes etc. are associated with infected teeth, there is capable of producing severe pain. a balance between microbial plasma mediators are present in aggression from the infecting circulation in inactive precursors form endodontic microbiota and the host and get activated on coming in contact defenses at the periradicular tissues. with irritants,for example : Hageman During chemo mechanical preparation factor when get activated after micro organisms are extruded into the contact with irritatnts produce multiple periradicular tissues, the host will face effects like production of bradykinnin a situation in which it is now and activation of clotting cascade. [2] challenged by a larger number of CHANGES IN CYCLIC NUCLEOTIDES irritants than it was before Bourne et al have shown that ,Consequently, there will be a character and intensity of transient disruption in the balance inflammatory and immune response is between aggression and defense, in regulated by harmones and such a way that an acute mediators. Increased levels of cAMP inflammatory response is mounted to inhibits mast cells degranulation. re-establish equilibrium .[1] (Figure 4) Whereas increase in cGMP levels Changes in periapical tissue pressure stimulate mast cell degranulation Mohorn et al showed that endodontic which results in increase in pain. therapy causes pressure changes in Studies have shown that in flare ups periapical area in both directions, study there is increased level of cGMP over carried out on dogs. cAMP concentrations. [6] A positive periapical pressure i.e IMMUNOLOGICAL RESPONSE excessive exudate not absorbed by In chronic and periapical lymphatic system, presses on nerve diseases presence of macrophages and endings causing pain. In contrast a lymphocytes indicates a both cell negative periapical pressure leads to mediated and humoral response. aspiration of microbes and altered tissue Despite of their protective effect the proteins from root canal to periapical immunologic response also contributes area resulting in increased inflammatory to destructive phase of reaction which response and pain. In such cases no can occur, causing perpetuations and drainage occurs when root canal is aggravation of inflammatory process.[6] opened. PSYCHOLOGICAL FACTORS EFFECTS OF CHEMICAL MEDIATORS Anxiety, fear, psychosis , apprehension, Chemical mediators can be in form of previous traumatic dental experience cell mediators, plasma mediators and

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 play an important role in mid- can be intensified and then result in treatment flare-ups .[6] lesion exacerbation.[1] (Figure 5) POSTOPERATIVE PAIN IN RE- Furthermore, environmental changes TREATMENT CASES induced by incomplete  Flare up rate is high . instrumentation have the potential to  During removal of the root filling induce virulence genes to be turned material and further on. instrumentation, filling remnants As a result of the increase in and infected debris tend to be microbial virulence, a previously pushed ahead of the files and to asymptomatic case may become be forced into the periradicular symptomatic. tissues, exacerbating inflammation Another form of environmental and causing pain. change induced by endodontic  Solvents used during filling intervention refers to the entrance of removal are also cytotoxic and oxygen in the root canal. may contribute to exacerbation of It has been suggested that this can the periradicular inflammation.[1] alter the oxidation–reduction potential INCOMPLETE INSTRUMENTATION in the root canal and as a The microbiota associated with consequence, acute exacerbation can primary endodontic infections is occur . usually established as a mixed SECONDARY INTRARADICULAR consortium, and alteration of part of INFECTIONS this consortium will affect both the These infections are caused by environment and the remaining microorganisms that were not present species. in the primary infection and have Potent exogenous forces represented gained entry into the root canal by chemomechanical preparation using system during treatment, between antimicrobial irrigants and intracanal appointments, or even after the medication are needed to eradicate conclusion of the endodontic microbial communities from the root treatment. canal system. However, incomplete Introduction of new microorganisms chemomechanical preparation can into the root canal system can occur disrupt the balance within the due to several ways, the most microbial community by eliminating common being a breach of the some inhibitory species and leaving aseptic chain during treatment . behind other previously inhibited If the microorganisms that gain access species, which can then overgrow. to the root canal are successful in If overgrown strains are virulent surviving into and colonizing such a and/or reach sufficient numbers, new environment, a secondary damage to the periradicular tissues infection will establish itself and may

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 be one of the causes of postoperative  Determine correct working length pain, providing that the newly by Radiographs,Apex locaters. [5] established microbial species are  Selection of instrumentation virulent and reach sufficient numbers technique that extrude less amount to induce acute periradicular s of debris apically.[5] inflammation.[1]  Crown-down techniques, MANAGEMENT OF FLARE –UPS irrespective of whether hand or As the etiology of flare ups is engine-driven instruments are multifactorial ,many treatment options used, usually extrude less debris have been empirically advocated. and should be elected for the Management of flare –ups can be instrumentation of infected root categorized as : canals. [5]  Preventive  Complete debridement [5]  Definitive  Thorough cleaning and shaping of PREVENTION OF FLAREUPS the root canal system and complete A history of preoperative pain or extirpation of vital pulp may swelling particular in case of necrotic decrease the incidence of flare and infected pulps,is one of the best ups.[5] predictors of interappoinment flare up.  Completion of chemomechanical However one should bear in mind that preparation in single visit.[5] flare up are often unpredictable,because  Use of an antimicrobial intracanal all infected cases have thereotically medicament between appointments inceased risk to develop in the treatment of infected root interappoinment flare up. canal.[5] Guidelines And Procedures To Prevent  Irrigation Preferably with Or Reduce The Incidence Of Flare Ups: combination of irrigants such as PROPER DIAGNOSIS: sodium hypochlorite and . Identify the correct tooth causing chlorohexidine pain.5  Occlusal reduction-The relief of pain . Ascertain whether tooth is vital or provided by occlusal reduction is non vital.5 due to the reduction of mechanical . Identify if tooth is associated with stimulation of sensitized periapical lesion. [5] nociceptors.Reduce tooth from  Determine correct working length [5] occlusion especially if apex is  Inaccurate measurement of the severely violated by over- working length may lead to under or instrumentation.[12] over instrumentation and extrusion  Placement of intracanal of debris, irrigant,medicaments or medicaments in multi visit root filling materials beyond apex.[5] canal treatment ,Calcium hydroxide has been recommended as an

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 intracanal medicament for DEFINITIVE TREATMENT prevention or the treatment of flare- The clinician should reassure the up. Chlorhexidine gluconate and patient. Once the diagnosis has been iodine potassium iodide are other confirmed that in fact it is the recently primary medicaments. treated tooth that is responsible for the  Not leaving teeth open for drainage. post-treatment symptoms, definitive  Avoid filing too close to the effective treatment must be rendered. radiographic apex. RE-INSTRUMENTATION  Maintaining the aseptic chain during Definitive treatment may involve re- intracanal procedures. [5,7] entering the symptomatic tooth. The TREATMENT OF INTERAPPOINTMENT involved tooth or area should be PAIN properly anesthetized prior to any  Hargreaves and Seltzer described treatment. The access cavity should then an integrated approach for the be opened and additional anatomy management and control of looked for that might have been missed odontogenic pain. This has been on the initial visit. Working lengths termed the ‘3D’ approach for pain should be reconfirmed, patency to the control: apical foramen obtained and a thorough 1. Diagnosis debridement with copious irrigation 2. Definitive treatment performed. Remaining tissue, 3. Drugs microorganisms and toxic products or DIAGNOSIS their extrusion are arguably the major Obtaining a thorough understanding of elements responsible for the post the patient’s chief complaint should be treatment symptoms . [1,3] the first step in proper management. 1(b) Cortical trephination Gathering information, such as on when Cortical trephination is defined as the the post-treatment symptoms began, surgical perforation of the alveolar bone are they intermittent or continuous, are in an attempt to release accumulated they mild, moderate or severe. periradicular tissue exudate. CLINICAL EXAMINATION Additionally, in the asymptomatic The following conditions should be patient, cortical trephination has been properly noted: shown to decrease by 16–25% post- 1. Areas of swelling operative pain incidence when 2. Discoloration performed prophylactically. 3. Ulcerations Moos et al. compared the difference in 4. Exudation post-operative pain relief in patients 5. Defective and/or lost restorations with acute periradicular pain of pulpal 6. Cracked or fractured teeth. origin when treated by either 7. Apparent changes in occlusal pulpectomy alone or pulpectomy with relationships. cortical trephination.There were no

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 significant differences between the INTRACANAL MEDICAMENTS groups. [3] Clinical studies have demonstrated that INCISION AND DRAINAGE (I&D) post-treatment pain is neither prevented In teeth where the endodontic nor relieved by medicaments such as treatment has not yet been completed, formocresol, camphorated paramono it may be advisable to re-enter the root chlorophenol, eugenol, iodine potassium canal system to further eliminate the iodide, Ledermix, or calcium hydroxide. original etiologic factors via However, the use of intracanal steroids , debridement, irrigation and the non-steriodal anti-inflammatory drugs placement of an antimicrobial dressing. (NSAIDs) or a corticosteroid– antibiotic If the abscess occurs after the obturation compound.has been shown to reduce of the root canal system, incision of the post-treatment pain. [1,3,15] fluctuant tissue is perhaps the only DRUGS reasonable emergency treatment, SYSTEMIC ANTIBIOTICS: provided the root canal filling is Antibiotics recommended only in cases adequate. of medically compromised patients at Drainage allows for the exudative high risk levels and in case of spreading components to be released from the infection that indicates failure of local periradicular tissues thus reducing host responses to control bacterial localized tissue pressure. irritants. It has been pointed out that leaving a Commonly prescribed antibiotics include tooth open is the most direct way to penicillin ,erthyromycin or allow for re-infection via the oral cephalosporin, metronidazole, microbiota .Weine advocated enlarging tinidazole, ornidazole and clindamycin the apical constriction to at least a size used against anaerobic bacteria.[9,15] #25 endodontic file to allow for drainage ANALGESICS through the tooth. Non-narcotic analgesics, NSAIDs and Antibiotics are usually not indicated in acetaminophen have effectively been cases of a localized abscess ,but they can used to treat the endodontic pain be used to supplement clinical patient. The combination of a NSAID and procedures in cases where there is poor acetominophen taken together show drainage and if the patient has a additive analgesia for treating dental concomitant , cellulitis, fever or pain. For pain that is not controlled by lymphadenopathy. NSAIDs and acetominophen, narcotic Poorly Filled Canals ,In cases of poorly analgesics are required.These may be filled canals and in addition to incision, given in combination with NSAIDs for the filling material should be removed in additive effects. [9,3,1,15] order to allow for additional pus PATIENT COUNSELING drainage through the root canal space. Detailed explanations of the complete [3,15] procedure, expected benefits and

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Vanti A.et al, Int J Dent Health Sci 2016; 3(4):778-789 possible pain responses of root canal Even though it has been demonstrated treatment to the patient, will help to that a flare-up has no significant reduce the patient’s anxiety, influence on the outcome of endodontic apprehension & tension because one treatment, its occurrence is extremely prefers to know what will happen if he undesirable for both the patient and the or she undergoes particular procedure clinician, and can undermine clinician– .[15] patient relationships. Postoperative instructions like proper Therefore, clinicians should employ scheduling of medicines,application of proper measures and follow appropriate ice, following the appropriate regimen of guidelines in an attempt to prevent the taking medicines etc will elevate the development of interappointment flare- patient’s pain threshold. [2,15] up. CONCLUSION:

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