Endodontic Failure Flashcards
Definitions related to endodontic treatment outcome?
- Healed: Both clinical and radiographic presentations are normal.
- ” Healing: It is a dynamic process, reduced radiolucency combined with normal clinical presentation.
- Disease: No change or increase in radiolucency, clinical signs mayor may not be present
Factors affecting the success or failure of root canal treatment in all cases (9)
- Diagnosis and treatment planning
- Radiographic interpretation
- Anatomy of the tooth and root canal system
- Debridement of root canal space
- Asepsis of treatment regimen
- Quality and extent of apical seal
- Quality of post endodontic restoration
- Systemic health of patient
- Skill of the operator
Factors affecting progmosis in particular case in rood canal treatment (6)
- Pulpal and periodontal status
- Size of periapical radiolucency
- Canal anatomy like calcification, presence of
- accessory or lateral canals,resorption, curvature.
- Crown and root fracture
- latrogenic errors
- Occlusal discrepancies
- Time of post-treatment evaluation
Local Factors responsible for endodontic failure
- Infection
- Excessive hemorrhage
- Chemical irritants
- Iatrogenic errors
a. Canal blockage and ledge
b. Incomplete debridement of the root canal system
c. Overinstrumentation
d. Separated instruments
e. Perforations
f. Incompletely filled teeth
g. Overfilling of root canals - Corrosion of root canal fillings
- Anatomie factors
- Root fractures
- Traumatic occlusion
- Periodontal considerations
Systemic Factors responsible for endodontic failure Local
- Nutritional deficiencies
- Diabetes mellitus
- Renal failure
- Blood dyscrasias
- Hormonal imbalance
- Autoimmune disorders
- Opportunistic
- infections
- Aging
- Patients on long-term steroid therapy
Describe infection, excessive hemorrhage and chemical irrigators in Endo dontic failures.
Infection
- If infected tissue is present, then host parasite relationship, virulence of microorganisms, and ability of infected tissues to heal in the presence of microorganisms are the main factors which influence repair of periapical tissues following endodontic therapy
- If apical seal or coronal restoration are not optimal :reinfection of root canal can occur.
Excessive Hemorrhage Extirpation of pulp and instrumentation beyond periapical tissues lead to excessive hemorrhage. Clump of extravasated blood cells and fluid must be resorbed, otherwise it acts as foreign body and nidus for bacterial growth, especially in the presence of infection.
Chemical Irritants Chemical irritants in the form of intracanal medicaments and Irrigating solution decrease The prognosis of endodontic therapy, if they get extruded in the periapical tissues.
Describe Canal blockage and ledge formation, Incomplete debridement of the root canal system, Over instrumentation, Instrument separation in endodonti failure
- Canal blockage and ledge formation
a. In cases with canal blockage and ledge formation, complete cleaning and shaping of the root canal system cannot be accomplished
b. Because of working short of the canal terminus, bacteria and tissue debris may remain in non-instrumented areaMcontributing to endodontic failure. - Incomplete debridement of the root canal system
a. Presence of infected and necrotic pulp tissue in root canal acts as the main irritant to the periapical tissues
b. Poor debridement can cause residual microorganisms, Their by-products and tissue debris to recolonize and contribute endodontic failure. 3. Over instrumentation a. Over instrumentation results in trauma to periodontal ligament and the alveolar bone:
thus affecting the success rate.
Describe Perforation, Incompletely filled teeth, Overfilling of root canals in endodontic failures
- Perforation
a. Perforation is the mechanical communication between the root canal system and the periodontium
b. Prognosis of endodontically treated tooth with perforations depends on many factors such as location (its closeness to gingival sulcus), time elapsed before defect is repaired, adequacy of perforation seal, and size of the perforation. - Incompletely filled teeth
a. Under-filling can occur due to incomplete instrumentation or ledge formation, blockage of canal, and improper measurements of working length
b. Remaining infected necrotic tissue, microorganism, and their by-products in inadequately instrumented and filled teeth cause continuous irritation to the Periradicular tissues and thus endodontic failure - Overfilling of root canals
a. 0verfilling of root canals, that is, obturation of the canal extending >2 mm beyond radiographicMapex. Filling material acts as a foreign body which may generate immunological response and cause continuous irritation of the periapical tissues
b. Biofilms present on extruded material containMtreatment resistant bacteria resulting in endodontic failure.
Talk about a anatomic, root fractures and traumatic occlusion.
Anatomic Factors Presence of curved canals, calcifications, lateral, and accessory canals, bifurcations, aberrant canal anatomy like C- or S-shaped canals may cause inadequate cleaning and shaping and thereby incomplete obturation, resulting in endodontic failure.
Root Fractures Partial or complete fractures of the roots can cause endodontic failure.
Traumatic Occlusion Traumatic occlusion causes endodontic failures because of its effect on periodontium.
Talk about corrosion in endodontic failures and perio considerations
Corrosion of Root Canal Fillings
- Silver cones show corrosion which is commonly seen in coronal and apical areas due to contact of tissue fluids either periapical exudation or saliva.
- Corrosion products are cytotoxic and act as tissue irritants causing persistent periapical inflammation.
Periodontal Considerations Recession of attachment apparatus may expose lateral canals to the oral fluids which can lead to reinfection of the root canal system because of percolation of fluids.
What can systemic factors in Endo failure cause and what are Contraindications of endodontic retreatment?
can intensify the response of periapical tissues to the irritants during endodontic therapy and also impair healing
Contraindications of endodontic retreatment
- Unfavorable root anatomy (shape, taper, remaining dentin thickness)
- Presence of untreatable root resorptions or perforations
- Presence of root or bifurcation caries
- insufficient crown/root ratio
What are steps of retreatment?
- Coronal disassembly
- Establish access to root canal system
- Remove canal obstructions and establish patency
- Thorough cleaning, shaping, and obturation of-the canal.
What’s coronal dis assembly and what are advantages?
- Endodontic retreatment procedures require removal of existingMcoronal restoration
- Though access can be made through the existing restoration ( it is removed if it has poor marginal adaptation or secondary caries).
Advantages of gaining access through original restoration
- Facilitate rubber dam placement
- Maintain form, function and esthetics
- Reduce cost of Replacement
What are Disadvantages of retaining restoration?
Disadvantages of retaining restoration
- Reduced visibility and accessibility
- Increased risks of irreparable errors
- Increased risks of microbial infection if crown margins are poorly adapted
Talk about evaluation of successful Endo