NEET MDS Lessons
Endodontics
Causes
Condensing osteitis is a mild irritation from pulpal disease that stimulates osteoblastic activity in the alveolar bone.
Symptoms
This disorder is usually asymptomatic. It is discovered during routine radiographic examination.
Diagnosis
The diagnosis is made from radiographs. Condensing osteitis appears in radiographs as a localized area of radio opacity surrounding the affected root. It is an area of dense bone with reduced trabecular pattern. The mandibular posterior teeth are most frequently affected.
Histopathology
Microscopically, condensing osteitis appears as an area of dense bone with reduced trabecular borders lined with osteoblasts. Chronic inflammatory cells, plasma cells, and lymphocytes are seen in the scant bone marrow.
Treatment
Removal of the irritant stimulus is recommended. Endodontic treatment should be initiated if signs and symptoms of irreversible pulpitis are diagnosed.
Prognosis
The prognosis for long-term retention of the tooth is excellent if root canal therapy is performed and if the tooth is restored satisfactory. Lesions of condensing osteitis may persist after endodontic treatment.
Techniques for Compaction of Gutta-Percha
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Lateral Condensation
- Description: This technique involves the use of a master cone of gutta-percha that is fitted to the prepared canal. Smaller accessory cones are then added and compacted laterally using a hand or rotary instrument.
- Advantages:
- Simplicity: Easy to learn and perform.
- Adaptability: Can be used in various canal shapes and sizes.
- Good Sealing Ability: Provides a dense fill and good adaptation to canal walls.
- Disadvantages:
- Time-Consuming: Can be slower than other techniques.
- Risk of Overfilling: Potential for extrusion of material beyond the apex if not carefully managed.
- Difficult in Complex Canals: May not adequately fill irregularly shaped canals.
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Vertical Condensation
- Description: In this technique, a master cone is placed in the canal, and heat is applied to the gutta-percha using a heated plugger. The softened gutta-percha is then compacted vertically.
- Advantages:
- Excellent Adaptation: Provides a better seal in irregularly shaped canals.
- Reduced Voids: The heat softens the gutta-percha, allowing it to flow into canal irregularities.
- Faster Technique: Generally quicker than lateral condensation.
- Disadvantages:
- Equipment Requirement: Requires specialized equipment (heated plugger).
- Risk of Overheating: Potential for damaging the tooth structure if the temperature is too high.
- Skill Level: Requires more skill and experience to perform effectively.
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Thermoplasticized Gutta-Percha Techniques
- Description: These techniques involve heating gutta-percha to a temperature that allows it to flow into the canal system. Methods include the use of a syringe (e.g., System B) or a warm vertical compaction technique.
- Advantages:
- Excellent Fill: Provides a three-dimensional fill of the canal system.
- Adaptability: Can adapt to complex canal anatomies.
- Reduced Voids: Minimizes the presence of voids and enhances sealing.
- Disadvantages:
- Equipment Cost: Requires specialized equipment, which can be expensive.
- Learning Curve: May require additional training to master the technique.
- Potential for Overfilling: Risk of extrusion if not carefully controlled.
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Single Cone Technique
- Description: This technique uses a single gutta-percha cone that is fitted to the canal and sealed with a sealer. It is often used with bioceramic or resin-based sealers.
- Advantages:
- Simplicity: Easy to perform and requires less time.
- Less Technique-Sensitive: Reduces the risk of procedural errors.
- Good for Certain Cases: Effective in cases with simpler canal systems.
- Disadvantages:
- Limited Adaptation: May not adequately fill complex canal systems.
- Potential for Voids: Increased risk of voids compared to other techniques.
- Less Retention: May not provide as strong a seal as other methods.
The Ca(OH)2, has been used by endodontists throughout the world since Hermann introduced it to dentistry in 1920.
It is a highly alkaline substance with a pH of approximately 12.5.
Calcium hydroxide has antibacterial properties and has the ability to induce repair and stimulate hard-tissue formation. The
bactericidal effects is conferred by its highly alkaline pH. The release of hydroxyl ions in an aqueous environment is related to the
antimicrobial property.
Hydroxyl ions are highly oxidizing free radicals that destroy bacteria by :
· Damaging the cytoplasmic membrane
· Protein denaturation
· Damaging bacterial DNA
The vehicle used to mix Ca(OH)2 and the manner in which it is dispensed has a significant role to play in achieving maximum
antibacterial effects as an intracanal medicament in endodontics.
In general, aqueous viscous or oily vehicles are used. The aqueous or water-soluble vehicles have high degree of solubility and
need multiple dressings to achieve desired results.
On the other hand, viscous vehicles like glycerine, polyethylene glycol, and propylene glycol promote slow solubility and hence
longer dressing intervals. The other medicaments combined with Ca(OH)2 include CMCP and 0.12% chlorhexidine.
Prevalence
Molars of older individuals most frequently present with cracked tooth syndrome. Most cases occur in teeth with class I restorations (39%) or in those that are unrestored (25%), but with an opposing plunger cusp occluding centrically against a marginal ridge. Mandibular molars are most commonly affected , followed by maxillary molars and maxillary premolars.
Symptoms
The patient usually complains of mild to excruciating pain at the initiation or
release of biting pressure. Such teeth may be sensitive for years because of an
incomplete fracture of enamel and dentin that produces only mild pain.
Eventually, this pain becomes severe when the fracture involves the pulp chamber
also. The pulp in these teeth may become necrotic.
Clinical features
Close examination of the crown of the tooth may disclose an enamel crack, which
may be better visualized by using the following methods:
Fiber optic light: this is used to transilluminate a fracture
line. Most cracks run mesiodistally and are rarely detected radiographically
when they are incomplete.
Dye: Alternatively, staining the fractute with a dye, such as
methylene blue, is a valuable aid to detect a fracture.
Tooth slooth: this is a small pyramid shaped plastic bite
block, with a small concavity at the apex of the pyramid to accommodate the
tooth cusp. This small indentation is placed over the cusp, and the patient is
asked to bite down. Thus, the occlusal force is directed to one cusp at a time,
exerting the desired pressure on the questionable cusp.
Root canal sealers are materials used in endodontics to fill the space between the root canal filling material (usually gutta-percha) and the walls of the root canal system. Their primary purpose is to provide a fluid-tight seal, preventing the ingress of bacteria and fluids, and to enhance the overall success of root canal treatment. Here’s a detailed overview of root canal sealers, including their types, properties, and clinical considerations.
Types of Root Canal Sealers
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Zinc Oxide Eugenol (ZOE) Sealers
- Composition: Zinc oxide powder mixed with eugenol (oil of cloves).
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Properties:
- Good sealing ability.
- Antimicrobial properties.
- Sedative effect on the pulp.
- Uses: Commonly used in conjunction with gutta-percha for permanent root canal fillings. However, it can be difficult to remove if retreatment is necessary.
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Resin-Based Sealers
- Composition: Composed of resins, fillers, and solvents.
-
Properties:
- Excellent adhesion to dentin and gutta-percha.
- Good sealing ability and low solubility.
- Aesthetic properties (some are tooth-colored).
- Uses: Suitable for various types of root canal systems, especially in cases requiring high bond strength and sealing ability.
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Calcium Hydroxide Sealers
- Composition: Calcium hydroxide mixed with a vehicle (such as glycol or water).
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Properties:
- Biocompatible and promotes healing.
- Antimicrobial properties.
- Can stimulate the formation of reparative dentin.
- Uses: Often used in cases where a temporary seal is needed or in apexification procedures.
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Glass Ionomer Sealers
- Composition: Glass ionomer cement (GIC) materials.
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Properties:
- Good adhesion to dentin.
- Fluoride release, which can help in preventing secondary caries.
- Biocompatible.
- Uses: Used in conjunction with gutta-percha, particularly in cases where fluoride release is beneficial.
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Bioceramic Sealers
- Composition: Made from calcium silicate and other bioceramic materials.
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Properties:
- Excellent sealing ability and biocompatibility.
- Hydrophilic, allowing for moisture absorption and expansion to fill voids.
- Promotes healing and tissue regeneration.
- Uses: Increasingly popular for permanent root canal fillings due to their favorable properties.
Properties of Ideal Root Canal Sealers
An ideal root canal sealer should possess the following properties:
- Biocompatibility: Should not cause adverse reactions in periapical tissues.
- Sealing Ability: Must provide a tight seal to prevent bacterial leakage.
- Adhesion: Should bond well to both dentin and gutta-percha.
- Flowability: Should be able to flow into irregularities and fill voids.
- Radiopacity: Should be visible on radiographs for easy identification.
- Ease of Removal: Should allow for easy retreatment if necessary.
- Antimicrobial Properties: Should inhibit bacterial growth.
Clinical Considerations
- Selection of Sealer: The choice of sealer depends on the clinical situation, the type of tooth being treated, and the specific properties required for the case.
- Application Technique: Proper application techniques are crucial for achieving an effective seal. This includes ensuring that the root canal is adequately cleaned and shaped before sealer application.
- Retreatment: Some sealers, like ZOE, can be challenging to remove during retreatment, while others, like bioceramic sealers, may offer better retrievability.
- Setting Time: The setting time of the sealer should be considered, especially in cases where immediate restoration is planned.
Conclusion
Root canal sealers play a vital role in the success of endodontic treatment by providing a seal that prevents bacterial contamination and promotes healing. Understanding the different types of sealers, their properties, and their clinical applications is essential for dental professionals to ensure effective and successful root canal therapy.