NEET MDS Lessons
Pedodontics
Anomalies of Number: problems in initiation stage
Hypodontia: 6% incidence; usually autosomal dominant (50% chance of passing to children) with variable expressivity (e.g., parent has mild while child has severe); most common missing permanent tooth (excluding 3rd molars) is Md 2nd premolar, 2nd most common is X lateral; oligodontia (at least 6 missing), and anodontia
1. Clincial implications: can interfere with function, lack of teeth → ↓ alveolar bone formation, esthetics, hard to replace in young children, implants only after growth completed, severe cases should receive genetic and systemic evaluation to see if other problems
2. Syndromes with hypodontia: Rieger syndrome, incontinentia pigmenti, Kabuki syndrome, Ellis-van Creveld syndrome, epidermolysis bullosa junctionalis, and ectodermal dysplasia (usually X-linked; sparse hair, unable to sweat, dysplastic nails)
Supernumerary teeth: aka hyperdontia; mesiodens when located in palatal midline; occur sporadically or as part of syndrome, common in cleft cases; delayed eruption often a sign that supernumeraries are preventing normal eruption
1. Multiple supernumerary teeth: cleidocranial dysplasia/dysostosis, Down’s, Apert, and Crouzon syndromes, etc.
Anomalies of Size: problems in morphodifferentiation stage
Microdontia: most commonly peg laterals; also in Down’s syndrome, hemifacial microsomia
Macrodontia: may be associated with hemifacial hypertrophy
Fusion: more common in primary dentition; union of two developing teeth
Gemination: more common in primary; incomplete division of single tooth bud → bifid crown, one pulp chamber; clinically distinguish from fusion by counting geminated tooth as one and have normal # teeth present (not in fusion)
Anomalies of Shape: errors during morphodifferentiation stage
Dens evaginatus: extra cusp in central groove/cingulum; fracture can → pulp exposure; most common in Orientals
Dens in dente: invagination of inner enamel epithelium → appearance of tooth within a tooth
Taurodontism: failure of Hertwig’s epithelial root sheath to invaginate to proper level → elongated (deep) pulp chamber, stunted roots; sporadic or associated with syndrome (e.g., amelogenesis imperfecta, Trichodento-osseous syndrome, ectodermal dysplasia)
Conical teeth: often associated with ectodermal dysplasia
Anomalies of Structure: problems during histodifferentiation, apposition, and mineralization stages
Dentinogenesis imperfecta: problem during histodifferentiation where defective dentin matrix → disorganized and atubular circumpulpal dentin; autosomal dominant inheritance; three types, one occurs with osteogenesis imperfecta (brittle bone syndrome); not sensitive despite exposed dentin; primary dentition has bulbous crowns, obliterated pulp chambers, bluish-grey or brownish-yellow teeth that are easily worn; permanent teeth often stained but can be sound
Amelogenesis imperfecta: heritable defect, independent from metabolic, syndromes, or systemic conditions (though similar defects seen with syndromes or environmental insults); four main types (hypoplastic, hypocalcified, hypomaturation, hypoplastic/hypomaturation with taurodontism); proper treatment addresses sensitivity, esthetics, VDO, caries and gingivitis prevention
Enamel hypoplasia: quantitative defect of enamel from problems in apposition stage; localized (caused by trauma) or generalized (caused by infection, metabolic disease, malnutrition, or hereditary disorders) effects; more common in malnourished children; least commonly Md incisors affected, often 1st molars; more susceptible to caries, excessive wearing → lost VDO, esthetic problems, and sensitivity to hot/cold
Enamel hypocalcification: during calcification stage
Fluorosis: excess F ingestion during calcification stage → intrinsic stain, mottled appearance, or brown staining and pitting; mild, moderate, or severe; porous enamel soaks up external stain
The psychoanalytical theory, primarily developed by Sigmund Freud, provides a framework for understanding human behavior and personality through two key models: the Topographic Model and the Psychic Model (or Triad). Here’s a detailed explanation of these concepts:
1. Topographic Model
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Overview: Freud's Topographic Model describes the structure of the human mind in three distinct layers: the conscious, preconscious, and unconscious mind.
- Conscious Mind:
- This is the part of the mind that contains thoughts, feelings, and perceptions that we are currently aware of. It is the "tip of the iceberg" and represents about 10% of the total mind.
- Preconscious Mind:
- This layer contains thoughts and memories that are not currently in conscious awareness but can be easily brought to consciousness. It acts as a bridge between the conscious and unconscious mind.
- Unconscious Mind:
- The unconscious mind holds thoughts, memories, and desires that are not accessible to conscious awareness. It is much larger than the conscious mind, representing about 90% of the total mind. This part of the mind is believed to influence behavior and emotions significantly, often without the individual's awareness.
- Conscious Mind:
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Iceberg Analogy:
- Freud often likened the mind to an iceberg, where the visible part above the water represents the conscious mind, while the much larger part submerged beneath the surface represents the unconscious mind.
2. Psychic Model (Triad)
The Psychic Model consists of three components that interact to shape personality and behavior:
A. Id:
- Description: The Id is the most primitive part of the personality and is present from birth. It operates entirely in the unconscious and is driven by the pleasure principle, seeking immediate gratification of basic instincts and desires (e.g., hunger, thirst, sexual urges).
- Characteristics: The Id is impulsive and does not consider reality or the consequences of actions. It is the source of instinctual drives and desires.
B. Ego:
- Description: The Ego develops from the Id during the second to sixth month of life. It operates primarily in the conscious and preconscious mind and is governed by the reality principle.
- Function: The Ego mediates between the desires of the Id and the constraints of reality. It helps individuals understand that not all impulses can be immediately satisfied and that some delay is necessary. The Ego employs defense mechanisms to manage conflicts between the Id and the external world.
C. Superego:
- Description: The Superego develops later in childhood, typically around the age of 3 to 6 years, as children internalize the moral standards and values of their parents and society.
- Function: The Superego represents the ethical component of personality and strives for perfection. It consists of two parts: the conscience, which punishes the ego with feelings of guilt for wrongdoing, and the ideal self, which rewards the ego with feelings of pride for adhering to moral standards.
- Characteristics: The Superego can be seen as the internalized voice of authority, guiding behavior according to societal norms and values.
Piaget's Cognitive Theory
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Active Learning:
- Piaget believed that children are not merely influenced by their environment; instead, they actively engage with it. They construct their understanding of the world through experiences and interactions.
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Adaptation:
- Adaptation is the process through which individuals adjust their cognitive structures to better understand their environment. This process consists of three functional variants: assimilation, accommodation, and equilibration.
The Three Functional Variants of Adaptation
i. Assimilation:
- Definition: Assimilation involves incorporating new information or experiences into existing cognitive schemas (mental frameworks). It is the process of recognizing and relating new objects or experiences to what one already knows.
- Example: A child who knows what a dog is may see a new breed of dog and recognize it as a dog because it fits their existing schema of "dog."
ii. Accommodation:
- Definition: Accommodation occurs when new information cannot be assimilated into existing schemas, leading to a modification of those schemas or the creation of new ones. It accounts for changing concepts and strategies in response to new experiences.
- Example: If the same child encounters a cat for the first time, they may initially try to assimilate it into their "dog" schema. However, upon realizing that it is not a dog, they must accommodate by creating a new schema for "cat."
iii. Equilibration:
- Definition: Equilibration is the process of balancing assimilation and accommodation to create stable understanding. It refers to the ongoing adjustments that individuals make to their cognitive structures to achieve a coherent understanding of the world.
- Example: When a child encounters a variety of animals, they may go through a cycle of assimilation and accommodation until they develop a comprehensive understanding of different types of animals, achieving a state of cognitive equilibrium.
Natal and neonatal teeth, also known by various synonyms such as congenital teeth, prediciduous teeth, dentition praecox, and foetal teeth. This topic is significant in pediatric dentistry and has implications for both diagnosis and treatment.
Etiology
The etiology of natal and neonatal teeth is multifactorial. Key factors include:
- Superficial Position of Tooth Germs: The positioning of tooth germs can lead to early eruption.
- Infection: Infections during pregnancy may influence tooth development.
- Malnutrition: Nutritional deficiencies can affect dental health.
- Eruption Acceleration: Febrile incidents or hormonal stimulation can hasten the eruption process.
- Genetic Factors: Hereditary transmission of a dominant autosomal gene may play a role.
- Osteoblastic Activities: Bone remodeling phenomena can impact tooth germ development.
- Hypovitaminosis: Deficiencies in vitamins can lead to developmental anomalies.
Associated Genetic Syndromes
Natal and neonatal teeth are often associated with several genetic syndromes, including:
- Ellis-Van Creveld Syndrome
- Riga-Fede Disease
- Pachyonychia Congenital
- Hallemann-Steriff Syndrome
- Sotos Syndrome
- Cleft Palate
Understanding these associations is crucial for comprehensive patient evaluation.
Incidence
The incidence of natal and neonatal teeth varies significantly, ranging from 1 in 6000 to 1 in 800 births. Notably:
- Approximately 90% of these teeth are normal primary teeth.
- In 85% of cases, the teeth are mandibular primary incisors.
- 5% are maxillary incisors and molars.
- The remaining 10% consist of supernumerary calcified structures.
Clinical Features
Clinically, natal and neonatal teeth may present with the following features:
- Morphologically, they can be conical or normal in size and shape.
- The color is typically opaque yellow-brownish.
- Associated symptoms may include dystrophic fingernails and hyperpigmentation.
Radiographic Evaluation
Radiographs are essential for assessing:
- The amount of root development.
- The relationship of prematurely erupted teeth to adjacent teeth.
Most prematurely erupted teeth are hypermobile due to limited root development.
Histological Characteristics
Histological examination reveals:
- Hypoplastic enamel with varying degrees of severity.
- Absence of root formation.
- Ample vascularized pulp.
- Irregular dentin formation.
- Lack of cementum formation.
These characteristics are critical for understanding the structural integrity of natal and neonatal teeth.
Harmful Effects
Natal and neonatal teeth can lead to several complications, including:
- Laceration of the lingual surface of the tongue.
- Difficulties for mothers wishing to breast-feed their infants.
Treatment Options
When considering treatment, extraction may be necessary. However, precautions must be taken:
- Avoid extractions until the 10th day of life to allow for the establishment of commensal flora in the intestine, which is essential for vitamin K production.
- If extractions are planned and the newborn has not been medicated with vitamin K immediately after birth, vitamin K supplements should be administered before the procedure to prevent hemorrhagic disease of the newborn (hypoprothrombinemia).
Degrees of Mental Disability
Mental disabilities are often classified based on the severity of cognitive impairment, which can be assessed using various intelligence scales, such as the Wechsler Intelligence Scale and the Stanford-Binet Scale. Below is a detailed overview of the degrees of mental disability, including IQ ranges and communication abilities.
1. Mild Mental Disability
- IQ Range: 55-69 (Wechsler Scale) or 52-67 (Stanford-Binet Scale)
- Description:
- Individuals in this category may have some difficulty with academic skills but can often learn basic academic and practical skills.
- They typically can communicate well enough for most communication needs and may function independently with some support.
- They may have social skills that allow them to interact with peers and participate in community activities.
2. Moderate Mental Disability
- IQ Range: 40-54 (Wechsler Scale) or 36-51 (Stanford-Binet Scale)
- Description:
- Individuals with moderate mental disability may have significant challenges in academic learning and require more support in daily living.
- Communication skills may be limited; they can communicate at a basic level with others but may struggle with more complex language.
- They often need assistance with personal care and may benefit from structured environments and support.
3. Severe or Profound Mental Disability
- IQ Range: 39 and below (Severe) or 35 and below (Profound)
- Description:
- Individuals in this category have profound limitations in cognitive functioning and adaptive behavior.
- Communication may be very limited; some may be mute or communicate only in grunts or very basic sounds.
- They typically require extensive support for all aspects of daily living, including personal care and communication.
Growth Spurts in Children
Growth in children does not occur at a constant rate; instead, it is characterized by periods of rapid increase known as growth spurts. These spurts are significant phases in physical development and can vary in timing and duration between individuals, particularly between boys and girls.
Growth Spurts: Sudden increases in growth that occur at specific times during development. These spurts are crucial for overall physical development and can impact various aspects of health and well-being.
Timing of Growth Spurts
The timing of growth spurts can be categorized into several key periods:
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Just Before Birth
- Description: A significant growth phase occurs in the fetus just prior to birth, where rapid growth prepares the infant for life outside the womb.
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One Year After Birth
- Description: Infants experience a notable growth spurt during their first year of life, characterized by rapid increases in height and weight as they adapt to their new environment and begin to develop motor skills.
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Mixed Dentition Growth Spurt
- Timing:
- Boys: 8 to 11 years
- Girls: 7 to 9 years
- Description: This growth spurt coincides with the transition from primary (baby) teeth to permanent teeth. It is a critical period for dental development and can influence facial growth and the alignment of teeth.
- Timing:
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Adolescent Growth Spurt
- Timing:
- Boys: 14 to 16 years
- Girls: 11 to 13 years
- Description: This is one of the most significant growth spurts, marking the onset of puberty. During this period, both boys and girls experience rapid increases in height, weight, and muscle mass, along with changes in body composition and secondary sexual characteristics.
- Timing:
Child Neglect and Munchausen Syndrome by Proxy
Overview
Child neglect is a serious form of maltreatment that can have profound effects on a child's physical, emotional, and psychological well-being. Understanding the different types of neglect is essential for identifying at-risk children and providing appropriate interventions. Additionally, Munchausen syndrome by proxy is a specific form of abuse that involves the fabrication or induction of illness in a child by a caregiver.
Types of Child Neglect
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Safety Neglect:
- Definition: A gross lack of direct or indirect supervision by parents or caretakers regarding the safety of the child.
- Examples:
- Leaving a young child unsupervised in potentially dangerous situations (e.g., near water, traffic, or hazardous materials).
- Failing to provide adequate supervision during activities that pose risks, such as playing outside or using equipment.
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Emotional Neglect:
- Definition: Inadequate affection and emotional support, which can manifest as a lack of nurturing or emotional responsiveness from caregivers.
- Examples:
- Lack of "mothering" or emotional warmth, leading to feelings of abandonment or unworthiness in the child.
- Permitting maladaptive behaviors, such as refusing necessary remedial care for diagnosed medical and emotional problems, which can hinder the child's development and well-being.
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Physical Neglect:
- Definition: Failure to care for a child according to accepted standards, particularly in meeting basic needs.
- Examples:
- Not providing adequate food, clothing, shelter, or hygiene.
- Failing to ensure that the child receives necessary medical care or attention for health issues.
Munchausen Syndrome by Proxy
- Definition: A form of child abuse in which a caregiver (usually a parent) fabricates or induces illness in a child to gain attention, sympathy, or other benefits.
- Mechanism:
- The caregiver may intentionally cause symptoms or exaggerate existing medical conditions, leading to unnecessary medical interventions.
- For example, a caregiver might induce chronic diarrhea in a child by administering laxatives or other harmful substances.
- Impact on the Child:
- Children subjected to this form of abuse may undergo numerous medical tests, treatments, and hospitalizations, which can lead to physical harm and psychological trauma.
- The child may develop a mistrust of medical professionals and experience long-term emotional and developmental issues.