NEET MDS Lessons
Pedodontics
Stages of Development
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Sensorimotor Stage (0-2 years):
- Overview: In this stage, infants learn about the world primarily through their senses and motor activities. They begin to interact with their environment and develop basic cognitive skills.
- Key Characteristics:
- Object Permanence: Understanding that objects continue to exist even when they cannot be seen.
- Exploration: Infants engage in play by manipulating objects, which helps them learn about cause and effect.
- Symbolic Play: Even at this early stage, children may begin to engage in simple forms of symbolic play, such as pretending a block is a car.
- Example in Dental Context: A child may play with toys while sitting in the dental chair, exploring their environment and becoming familiar with the setting.
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Pre-operational Stage (2-6 years):
- Overview: During this stage, children begin to use language and engage in symbolic play, but their thinking is still intuitive and egocentric. They struggle with understanding the perspectives of others.
- Key Characteristics:
- Animism: The belief that inanimate objects have feelings and intentions (e.g., thinking a toy can feel sad).
- Constructivism: Children actively construct their understanding of the world through experiences and interactions.
- Symbolic Play: Children engage in imaginative play, using objects to represent other things (e.g., using a stick as a sword).
- Example: A child might pretend that a stuffed animal is talking or has feelings, demonstrating animism.
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Concrete Operational Stage (6-12 years):
- Overview: In this stage, children begin to think logically about concrete events. They can perform operations and understand the concept of conservation (the idea that quantity doesn’t change even when its shape does).
- Key Characteristics:
- Ego-centrism: While children in this stage are less egocentric than in the pre-operational stage, they may still struggle to see things from perspectives other than their own.
- Logical Thinking: Children can organize objects into categories and understand relationships between them.
- Conservation: Understanding that certain properties (like volume or mass) remain the same despite changes in form or appearance.
- Example: A child may understand that pouring water from a short, wide glass into a tall, narrow glass does not change the amount of water.
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Formal Operational Stage (11-15 years):
- Overview: In this final stage, adolescents develop the ability to think abstractly, reason logically, and use deductive reasoning. They can consider hypothetical situations and think about possibilities.
- Key Characteristics:
- Abstract Thinking: Ability to think about concepts that are not directly tied to concrete objects (e.g., justice, freedom).
- Hypothetical-Deductive Reasoning: Ability to formulate hypotheses and systematically test them.
- Metacognition: Awareness and understanding of one’s own thought processes.
- Example: An adolescent can discuss moral dilemmas or scientific theories, considering various outcomes and implications.
Devitalisation Pulpotomy (Two-Stage Procedure)
The two-stage devitalisation pulpotomy is a dental procedure aimed at treating exposed primary pulp tissue. This technique involves the use of paraformaldehyde to fix both coronal and radicular pulp tissues, ensuring effective devitalization. The medicaments employed in this procedure possess devitalizing, mummifying, and bactericidal properties, which are crucial for the success of the treatment.
Key Features of the Procedure:
- Two-Stage Approach: The procedure is divided into two stages, allowing for thorough treatment of the pulp tissue.
- Use of Paraformaldehyde: Paraformaldehyde is a key component in the medicaments, providing effective fixation and devitalization of the pulp.
- Medicaments: The following formulations are commonly used in the procedure:
Medicament Formulations:
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Gysi Triopaste:
- Tricresol: 10 ml
- Cresol: 20 ml
- Glycerin: 4 ml
- Paraformaldehyde: 20 ml
- Zinc Oxide: 60 g
Gysi Triopaste is known for its strong devitalizing and bactericidal effects, making it effective for pulp treatment.
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Easlick’s Paraformaldehyde Paste:
- Paraformaldehyde: 1 g
- Procaine Base: 0.03 g
- Powdered Asbestos: 0.05 g
- Petroleum Jelly: 125 g
- Carmine (for coloring)
This paste combines paraformaldehyde with a local anesthetic (Procaine) to enhance patient comfort during the procedure.
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Paraform Devitalizing Paste:
- Paraformaldehyde: 1 g
- Lignocaine: 0.06 g
- Propylene Glycol: 0.50 ml
- Carbowax 1500: 1.30 g
- Carmine (for coloring)
This formulation also includes Lignocaine for local anesthesia, providing additional comfort during treatment.
Diagnostic Tools in Dentistry
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Fiber Optic Transillumination (FOTI):
- Principle: FOTI utilizes the difference in light transmission between sound and decayed tooth structure. Healthy tooth structure allows light to pass through, while decayed areas absorb light, resulting in a darkened shadow along the path of dentinal tubules.
- Application: This technique is particularly useful for detecting interproximal caries and assessing the extent of decay without the need for radiation.
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Laser Detection:
- Argon Laser:
- Principle: Argon laser light is used to illuminate the tooth, and it can reveal carious lesions by producing a dark, fiery orange-red color in areas of decay.
- Application: This method enhances the visualization of carious lesions and can help in the early detection of dental caries.
- Argon Laser:
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DIAGNOdent:
- Principle: DIAGNOdent is a laser fluorescence device that detects caries based on the fluorescence emitted by decayed tooth structure. It is sensitive to changes in the mineral content of the tooth.
- Application: This tool is effective in identifying the precavitation stage of caries and quantifying the amount of demineralization present in the tooth. It allows for early intervention and monitoring of carious lesions.
Erythroblastosis fetalis
Blue-green colour of primary teeth only. It is due to excessive haemolysis of
RBC. The Staining occurs due to diffusion of bilirubin and biliverdin into the
dentin
Porphyria
Purplish brown pigmentation. to light and blisters on The other features hands
and face e Hypersensitivity are are red red coloured urine, urine,
Cystic fibrosis
(Yellowish gray to dark brown. It is due to tetracycline, which is the drug of
choice in this disease
Tetracycline
Yellow or yellow-brown pigmentation in dentin and to a lesser extent in enamel
that are calcifying during the time the drug is administered. The teeth
fluoresce yellow under UV light
Pulpotomy
Pulpotomy is a dental procedure that involves the surgical removal of the coronal portion of the dental pulp while leaving the healthy pulp tissue in the root canals intact. This procedure is primarily performed on primary (deciduous) teeth but can also be indicated in certain cases for permanent teeth. The goal of pulpotomy is to preserve the vitality of the remaining pulp tissue, alleviate pain, and maintain the tooth's function.
Indications for Pulpotomy
Pulpotomy is indicated in the following situations:
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Deep Carious Lesions: When a tooth has a deep cavity that has reached the pulp but there is no evidence of irreversible pulpitis or periapical pathology.
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Trauma: In cases where a tooth has been traumatized, leading to pulp exposure, but the pulp is still vital and healthy.
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Asymptomatic Teeth: Teeth that are asymptomatic but have deep caries that are close to the pulp can be treated with pulpotomy to prevent future complications.
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Primary Teeth: Pulpotomy is commonly performed on primary teeth that are expected to exfoliate naturally, allowing for the preservation of the tooth until it is ready to fall out.
Contraindications for Pulpotomy
Pulpotomy is not recommended in the following situations:
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Irreversible Pulpitis: If the pulp is infected or necrotic, a pulpotomy is not appropriate, and a pulpectomy or extraction may be necessary.
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Periapical Pathology: The presence of periapical radiolucency or other signs of infection at the root apex indicates that the pulp is not healthy enough to be preserved.
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Extensive Internal Resorption: If there is significant internal resorption of the tooth structure, the tooth may not be viable for pulpotomy.
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Inaccessible Canals: Teeth with complex canal systems that cannot be adequately accessed may not be suitable for this procedure.
The Pulpotomy Procedure
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Anesthesia: Local anesthesia is administered to ensure the patient is comfortable and pain-free during the procedure.
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Access Opening: A high-speed bur is used to create an access opening in the crown of the tooth to reach the pulp chamber.
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Removal of Coronal Pulp: The coronal portion of the pulp is carefully removed using specialized instruments. This step is crucial to eliminate any infected or necrotic tissue.
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Hemostasis: After the coronal pulp is removed, the area is treated to achieve hemostasis (control of bleeding). This may involve the use of a medicated dressing or hemostatic agents.
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Application of Diluted Formocresol: A diluted formocresol solution (typically a 1:5 or 1:10 dilution) is applied to the remaining pulp tissue. Formocresol acts as a fixative and has antibacterial properties, helping to preserve the vitality of the remaining pulp and prevent infection.
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Pulp Dressing: A biocompatible material, such as calcium hydroxide or mineral trioxide aggregate (MTA), is placed over the remaining pulp tissue to promote healing and protect it from further injury.
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Temporary Restoration: The access cavity is sealed with a temporary restoration to protect the tooth until a permanent restoration can be placed.
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Follow-Up: The patient is scheduled for a follow-up appointment to monitor the tooth's healing and to place a permanent restoration, such as a stainless steel crown, if the tooth is a primary tooth.
Major Antimicrobial Proteins of Human Whole Saliva
Human saliva contains a variety of antimicrobial proteins that play crucial roles in oral health by protecting against pathogens, aiding in digestion, and maintaining the balance of the oral microbiome. Below is a summary of the major antimicrobial proteins found in human whole saliva, their functions, and their targets.
1. Non-Immunoglobulin (Innate) Proteins
These proteins are part of the innate immune system and provide immediate defense against pathogens.
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Lysozyme
- Major Target/Function:
- Targets gram-positive bacteria and Candida.
- Functions by hydrolyzing the peptidoglycan layer of bacterial cell walls, leading to cell lysis.
- Major Target/Function:
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Lactoferrin
- Major Target/Function:
- Targets bacteria, yeasts, and viruses.
- Functions by binding iron, which inhibits bacterial growth (iron sequestration) and has direct antimicrobial activity.
- Major Target/Function:
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Salivary Peroxidase and Myeloperoxidase
- Major Target/Function:
- Targets bacteria.
- Functions in the decomposition of hydrogen peroxide (H2O2) to produce antimicrobial compounds.
- Major Target/Function:
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Histatin
- Major Target/Function:
- Targets fungi (especially Candida) and bacteria.
- Functions as an antifungal and antibacterial agent, promoting wound healing and inhibiting microbial growth.
- Major Target/Function:
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Cystatins
- Major Target/Function:
- Targets various proteases.
- Functions as protease inhibitors, helping to protect tissues from proteolytic damage and modulating inflammation.
- Major Target/Function:
2. Agglutinins
Agglutinins are glycoproteins that promote the aggregation of microorganisms, enhancing their clearance from the oral cavity.
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Parotid Saliva
- Major Target/Function:
- Functions in the agglutination/aggregation of a number of microorganisms, facilitating their removal from the oral cavity.
- Major Target/Function:
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Glycoproteins
- Major Target/Function:
- Functions similarly to agglutinins, promoting the aggregation of bacteria and other microorganisms.
- Major Target/Function:
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Mucins
- Major Target/Function:
- Functions in the inhibition of adhesion of pathogens to oral surfaces, enhancing clearance and protecting epithelial cells.
- Major Target/Function:
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β2-Microglobulin
- Major Target/Function:
- Functions in the enhancement of phagocytosis, aiding immune cells in recognizing and eliminating pathogens.
- Major Target/Function:
3. Immunoglobulins
Immunoglobulins are part of the adaptive immune system and provide specific immune responses.
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Secretory IgA
- Major Target/Function:
- Targets bacteria, viruses, and fungi.
- Functions in the inhibition of adhesion of pathogens to mucosal surfaces, preventing infection.
- Major Target/Function:
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IgG
- Major Target/Function:
- Functions similarly to IgA, providing additional protection against a wide range of pathogens.
- Major Target/Function:
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IgM
- Major Target/Function:
- Functions in the agglutination of pathogens and enhancement of phagocytosis.
- Major Target/Function:
Laminate Veneer Technique
The laminate veneer technique is a popular cosmetic dental procedure that enhances the esthetic appearance of teeth. This technique involves the application of thin shells of porcelain or composite resin to the facial surfaces of teeth, simulating the natural hue and appearance of healthy tooth structure.
Advantages of Laminate Veneers
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Esthetic Improvement:
- Laminate veneers provide significant esthetic enhancement, allowing for the restoration of teeth to a natural appearance.
- When properly finished, these restorations closely mimic the color and translucency of natural teeth.
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Gingival Tolerance:
- Laminate restorations are generally well tolerated by gingival tissues, even if the contour of the veneers is slightly excessive.
- Maintaining good oral hygiene is crucial, but studies have shown that gingival health can be preserved around these restorations in cooperative patients.
Preparation Technique
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Intraenamel Preparation:
- The preparation for laminate veneers involves the removal of 0.5 to 1 mm of facial enamel.
- The preparation tapers to about 0.25 to 0.5 mm at the cervical margin, ensuring a smooth transition and adequate bonding surface.
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Cervical Margin:
- The cervical margin should be finished in a well-defined chamfer that is level with the crest of the gingival margin or positioned no more than 0.5 mm subgingivally.
- This careful placement helps to minimize the risk of gingival irritation and enhances the esthetic outcome.
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Incisal Margin:
- The incisal margin may end just short of the incisal edge or may include the entire incisal edge, terminating on the lingual surface.
- It is advisable to avoid placing incisal margins where direct incising forces occur, as this can compromise the integrity of the veneer.
Bonded Porcelain Techniques
- Significance:
- Bonded porcelain techniques are highly valuable in cosmetic dentistry, providing a strong and durable restoration that can withstand the forces of mastication while enhancing the appearance of the teeth.
- Application:
- These techniques involve the use of adhesive bonding agents to secure the veneers to the prepared tooth surface, ensuring a strong bond and longevity of the restoration.