NEET MDS Lessons
Pedodontics
Indirect Pulp Capping
Indirect pulp capping is a dental procedure designed to treat teeth with deep carious lesions that are close to the pulp but do not exhibit pulp exposure. The goal of this treatment is to preserve the vitality of the pulp while allowing for the formation of secondary dentin, which can help protect the pulp from further injury and infection.
Procedure Overview
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Initial Appointment:
During the first appointment, the dentist excavates all superficial carious dentin. However, any dentin that is affected but not infected (i.e., it is still healthy enough to maintain pulp vitality) is left intact if it is close to the pulp. This is crucial because leaving a thin layer of affected dentin can help protect the pulp from exposure and further damage. -
Pulp Dressing:
After the excavation, a pulp dressing is placed over the remaining affected dentin. Common materials used for this dressing include:- Calcium Hydroxide: Promotes the formation of secondary dentin and has antibacterial properties.
- Glass Ionomer Materials: Provide a good seal and release fluoride, which can help in remineralization.
- Hybrid Ionomer Materials: Combine properties of both glass ionomer and resin-based materials.
The tooth is then sealed temporarily, and the patient is scheduled for a follow-up appointment, typically within 6 to 12 months.
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Second Appointment:
At the second appointment, the dentist removes the temporary restoration and excavates any remaining carious material. The floor of the cavity is carefully examined for any signs of pulp exposure. If no exposure is found and the tooth has remained asymptomatic, the treatment is deemed successful. -
Permanent Restoration:
If the pulp is intact, a permanent restoration is placed. The materials used for the final restoration can vary based on the tooth's location and the clinical situation. Options include:- For Primary Dentition: Glass ionomer, hybrid ionomer, composite, compomer, amalgam, or stainless steel crowns.
- For Permanent Dentition: Composite, amalgam, stainless steel crowns, or cast crowns.
Indications for Indirect Pulp Capping
Indirect pulp capping is indicated when the following conditions are met:
- Absence of Prolonged Pain: The tooth should not have a history of prolonged or repeated episodes of pain, such as unprovoked toothaches.
- No Radiographic Evidence of Pulp Exposure: Preoperative X-rays must not show any carious penetration into the pulp chamber.
- Absence of Pathology: There should be no evidence of furcal or periapical pathology. It is essential to assess whether the root ends are completely closed and to check for any pathological changes, especially in anterior teeth.
- No Percussive Symptoms: The tooth should not exhibit any symptoms upon percussion.
Evaluation and Restoration After Indirect Pulp Therapy
After the indirect pulp therapy, the following evaluations are crucial:
- Absence of Subjective Complaints: The patient should report no toothaches or discomfort.
- Radiographic Evaluation: After 6 to 12 months, periapical and bitewing X-rays should show deposition of new secondary dentin, indicating that the pulp is healthy and responding well to treatment.
- Final Restoration: If no pulp exposure is observed after the removal of the temporary restoration and any remaining soft dentin, a permanent restoration can be placed.
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
Recurrent Aphthous Ulcers (Canker Sores)
Overview of Recurrent Aphthous Ulcers (RAU)
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Definition:
- Recurrent aphthous ulcers, commonly known as canker sores, are painful ulcerations that occur on the unattached mucous membranes of the mouth. They are characterized by their recurrent nature and can significantly impact the quality of life for affected individuals.
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Demographics:
- RAU is most prevalent in school-aged children and young adults, with a peak incidence between the ages of 10 and 19 years.
- It is reported to be the most common mucosal disorder across various ages and races globally.
Clinical Features
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Characteristics:
- RAU is defined by recurrent ulcerations on the moist mucous membranes of the mouth.
- Lesions can be discrete or confluent, forming rapidly in certain areas.
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They typically feature:
- A round to oval crateriform base.
- Raised, reddened margins.
- Significant pain.
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Types of Lesions:
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Minor Aphthous Ulcers:
- Usually single, smaller lesions that heal without scarring.
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Major Aphthous Ulcers (RAS):
- Larger, more painful lesions that may take longer to heal and can leave scars.
- Also referred to as periadenitis mucosa necrotica recurrens or Sutton disease.
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Herpetiform Ulcers:
- Multiple small lesions that can appear in clusters.
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Minor Aphthous Ulcers:
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Duration and Healing:
- Lesions typically persist for 4 to 12 days and heal uneventfully, with scarring occurring only rarely and usually in cases of unusually large lesions.
Epidemiology
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Prevalence:
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The condition occurs approximately three times more frequently in white
children compared to black children.
- Prevalence estimates of RAU range from 2% to 50%, with most estimates falling between 5% and 25%. Among medical and dental students, the estimated prevalence is between 50% and 60%.
Associated Conditions
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Systemic Associations:
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RAS has been linked to several systemic diseases, including:
- PFAPA Syndrome: Periodic fever, aphthous stomatitis, pharyngitis, and adenitis.
- Behçet Disease: A systemic condition characterized by recurrent oral and genital ulcers.
- Crohn's Disease: An inflammatory bowel disease that can present with oral manifestations.
- Ulcerative Colitis: Another form of inflammatory bowel disease.
- Celiac Disease: An autoimmune disorder triggered by gluten.
- Neutropenia: A condition characterized by low levels of neutrophils, leading to increased susceptibility to infections.
- Immunodeficiency Syndromes: Conditions that impair the immune system.
- Reiter Syndrome: A type of reactive arthritis that can present with oral ulcers.
- Systemic Lupus Erythematosus: An autoimmune disease that can cause various oral lesions.
- MAGIC Syndrome: Mouth and genital ulcers with inflamed cartilage.
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RAS has been linked to several systemic diseases, including:
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:
Theories of Child Psychology
Child psychology encompasses a variety of theories that explain how children develop emotionally, cognitively, and behaviorally. These theories can be broadly classified into two main groups: psychodynamic theories and theories of learning and development of behavior. Additionally, Margaret S. Mahler's theory of development offers a unique perspective on child development.
I. Psychodynamic Theories
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Psychosexual Theory / Psychoanalytical Theory (Sigmund Freud, 1905):
- Overview: Freud's theory posits that childhood experiences significantly influence personality development and behavior. He proposed that children pass through a series of psychosexual stages (oral, anal, phallic, latency, and genital) where the focus of pleasure shifts to different erogenous zones.
- Key Concepts:
- Id, Ego, Superego: The id represents primal desires, the ego mediates between the id and reality, and the superego embodies moral standards.
- Fixation: If a child experiences conflicts during any stage, they may become fixated, leading to specific personality traits in adulthood.
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Psychosocial Theory / Model of Personality Development (Erik Erikson, 1963):
- Overview: Erikson expanded on Freud's ideas by emphasizing social and cultural influences on development. He proposed eight stages of psychosocial development, each characterized by a central conflict that must be resolved for healthy personality development.
- Key Stages:
- Trust vs. Mistrust (Infancy)
- Autonomy vs. Shame and Doubt (Early Childhood)
- Initiative vs. Guilt (Preschool Age)
- Industry vs. Inferiority (School Age)
- Identity vs. Role Confusion (Adolescence)
- Intimacy vs. Isolation (Young Adulthood)
- Generativity vs. Stagnation (Middle Adulthood)
- Integrity vs. Despair (Late Adulthood)
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Cognitive Theory (Jean Piaget, 1952):
- Overview: Piaget's theory focuses on the cognitive development of children, proposing that they actively construct knowledge through interactions with their environment. He identified four stages of cognitive development.
- Stages:
- Sensorimotor Stage (0-2 years): Knowledge through sensory experiences and motor actions.
- Preoperational Stage (2-7 years): Development of language and symbolic thinking, but egocentric and intuitive reasoning.
- Concrete Operational Stage (7-11 years): Logical thinking about concrete events; understanding of conservation and reversibility.
- Formal Operational Stage (12 years and up): Abstract reasoning and hypothetical thinking.
II. Theories of Learning and Development of Behavior
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Hierarchy of Needs (Abraham Maslow, 1954):
- Overview: Maslow proposed a hierarchy of needs that motivates human behavior. He suggested that individuals must satisfy lower-level needs before addressing higher-level needs.
- Levels:
- Physiological Needs (food, water, shelter)
- Safety Needs (security, stability)
- Love and Belongingness Needs (relationships, affection)
- Esteem Needs (self-esteem, recognition)
- Self-Actualization (realizing personal potential)
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Social Learning Theory (Albert Bandura, 1963):
- Overview: Bandura emphasized the role of observational learning, imitation, and modeling in behavior development. He proposed that children learn behaviors by observing others and the consequences of those behaviors.
- Key Concepts:
- Reciprocal Determinism: Behavior, personal factors, and environmental influences interact to shape learning.
- Bobo Doll Experiment: Demonstrated that children imitate aggressive behavior observed in adults.
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Classical Conditioning (Ivan Pavlov, 1927):
- Overview: Pavlov's theory focuses on learning through association. He demonstrated that a neutral stimulus, when paired with an unconditioned stimulus, can elicit a conditioned response.
- Example: Pavlov's dogs learned to salivate at the sound of a bell when it was associated with food.
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Operant Conditioning (B.F. Skinner, 1938):
- Overview: Skinner's theory emphasizes learning through consequences. Behaviors followed by reinforcement are more likely to be repeated, while those followed by punishment are less likely to occur.
- Key Concepts:
- Reinforcement: Increases the likelihood of a behavior (positive or negative).
- Punishment: Decreases the likelihood of a behavior (positive or negative).
III. Margaret S. Mahlers Theory of Development
- Overview: Mahler's theory focuses on the psychological development of infants and young children, particularly the process of separation-individuation. She proposed that children go through stages as they develop a sense of self and differentiate from their primary caregiver.
- Key Stages:
- Normal Autistic Phase: Birth to 2 months; the infant is primarily focused on internal stimuli.
- Normal Symbiotic Phase: 2 to 5 months; the infant begins to recognize the caregiver but does not differentiate between self and other.
- Separation-Individuation Phase: 5 to 24 months; the child starts to separate from the caregiver and develop a sense of individuality through exploration and interaction with the environment.
Anti-Infective and Anticariogenic Agents in Human Milk
Human milk is not only a source of nutrition for infants but also contains various bioactive components that provide anti-infective and anticariogenic properties. These components play a crucial role in protecting infants from infections and promoting oral health. Below are the key agents found in human milk:
1. Immunoglobulins
- Secretory IgA: The predominant immunoglobulin in human milk, secretory IgA plays a vital role in mucosal immunity by preventing the attachment of pathogens to mucosal surfaces.
- IgG and IgM: These immunoglobulins also contribute to the immune defense, with IgG providing systemic immunity and IgM being involved in the initial immune response.
2. Cellular Elements
- Lymphoid Cells: These cells are part of the immune system and help in the recognition and response to pathogens.
- Polymorphonuclear Leukocytes (Polymorphs): These white blood cells are essential for the innate immune response, helping to engulf and destroy pathogens.
- Macrophages: These cells play a critical role in phagocytosis and the immune response, helping to clear infections.
- Plasma Cells: These cells produce antibodies, contributing to the immune defense.
3. Complement System
- C3 and C4 Complement Proteins: These components of the complement system have opsonic and chemotactic activities, enhancing the ability of immune cells to recognize and eliminate pathogens. They promote inflammation and attract immune cells to sites of infection.
4. Unsaturated Lactoferrin and Transferrin
- Lactoferrin: This iron-binding protein has antimicrobial properties, inhibiting the growth of bacteria and fungi by depriving them of iron.
- Transferrin: Similar to lactoferrin, transferrin also binds iron and plays a role in iron metabolism and immune function.
5. Lysozyme
- Function: Lysozyme is an enzyme that breaks down bacterial cell walls, providing antibacterial activity. It helps protect the infant from bacterial infections.
6. Lactoperoxidase
- Function: This enzyme produces reactive oxygen species that have antimicrobial effects, contributing to the overall antibacterial properties of human milk.
7. Specific Inhibitors (Non-Immunoglobulins)
- Antiviral and Antistaphylococcal Factors: Human milk contains specific factors that inhibit viral infections and the growth of Staphylococcus bacteria, providing additional protection against infections.
8. Growth Factors for Lactobacillus Bifidus
- Function: Human milk contains growth factors that promote the growth of beneficial bacteria such as Lactobacillus bifidus, which plays a role in maintaining gut health and preventing pathogenic infections.
9. Para-Aminobenzoic Acid (PABA)
- Function: PABA may provide some protection against malaria, highlighting the potential role of human milk in offering broader protective effects against various infections.