NEET MDS Synopsis
Mahlers Stages of Development
PedodonticsMahler's Stages of Development
Normal Autistic Phase (0-1 year):
Overview: In this initial phase, infants are
primarily focused on their own needs and experiences. They are not yet
aware of the external world or the presence of others.
Characteristics: Infants are in a state of
self-absorption, and their primary focus is on basic needs such as
feeding and comfort. They may not respond to external stimuli or
caregivers in a meaningful way.
Application in Pedodontics: During this stage,
dental professionals may not have direct interactions with infants, as
their focus is on basic care. However, creating a soothing environment
can help infants feel secure during dental visits.
Normal Symbiotic Phase (3-4 weeks to 4-5 months):
Overview: In this phase, infants begin to develop a
sense of connection with their primary caregiver, typically the mother.
They start to recognize the caregiver as a source of comfort and
security.
Characteristics: Infants may show signs of
attachment and begin to respond to their caregiver's presence. They rely
on the caregiver for emotional support and comfort.
Application in Pedodontics: During dental visits,
having a parent or caregiver present can help infants feel more secure.
Dental professionals can encourage caregivers to hold or comfort the
child during procedures to foster a sense of safety.
Separation-Individuation Process (5 to 36 months):
This process is further divided into several sub-stages, each
representing a critical aspect of a child's development of independence
and self-identity.
Differentiation (5-10 months):
Overview: Infants begin to differentiate
themselves from their caregivers. They start to explore their
environment while still seeking reassurance from their caregiver.
Application in Pedodontics: Dental
professionals can encourage exploration by allowing children to
touch and interact with dental tools in a safe manner, helping them
feel more comfortable.
Practicing Period (10-16 months):
Overview: During this stage, children actively
practice their newfound mobility and independence. They may explore
their surroundings more confidently.
Application in Pedodontics: Allowing children
to walk or move around the dental office (within safe limits) can
help them feel more in control and less anxious.
Rapprochement (16-24 months):
Overview: Children begin to seek a balance
between independence and the need for closeness to their caregiver.
They may alternate between wanting to explore and wanting comfort.
Application in Pedodontics: Dental
professionals can support this stage by providing reassurance and
comfort when children express anxiety, while also encouraging them
to engage with the dental environment.
Consolidation and Object Constancy (24-36 months):
Overview: In this final sub-stage, children
develop a more stable sense of self and an understanding that their
caregiver exists even when not in sight. They begin to form a more
complex understanding of relationships.
Application in Pedodontics: By this stage,
children can better understand the dental process and may be more
willing to cooperate. Dental professionals can explain procedures in
simple terms, reinforcing the idea that the dentist is there to help
Muscles of the Soft Palate
AnatomyMuscles of the Soft Palate
The Levator Veli Palatini (Levator Palati)
Superior attachment: cartilage of the auditory tube and petrous part of temporal bone.
Inferior attachment: palatine aponeurosis.
Innervation: pharyngeal branch of vagus via pharyngeal plexus.
This cylindrical muscle runs inferoanteriorly, spreading out in the soft palate, where it attaches to the superior surface of the palatine aponeurosis.
It elevates the soft palate, drawing it superiorly and posteriorly.
It also opens the auditory tube to equalise air pressure in the middle ear and pharynx.
The Tensor Veli Palatini (Tensor Palati)
Superior attachment: scaphoid fossa of medial pterygoid plate, spine of sphenoid bone, and cartilage of auditory tube.
Inferior attachment: palatine aponeurosis.
Innervation: medial pterygoid nerve (a branch of the mandibular nerve).
This thin, triangular muscle passes inferiorly, and hooks around the hamulus of the medial pterygoid plate.
It then inserts into the palatine aponeurosis.
This muscle tenses the soft palate by using the hamulus as a pulley.
It also pulls the membranous portion of the auditory tube open to equalise air pressure of the middle ear and pharynx.
The Palatoglossus Muscle
Superior attachment: palatine aponeurosis.
Inferior attachment: side of tongue.
Innervation: cranial part of accessory nerve (CN XI) through the pharyngeal branch of vagus (CN X) via the pharyngeal plexus.
This muscle, covered by mucous membrane, forms the palatoglossal arch.
The palatoglossus elevates the posterior part of the tongue and draws the soft palate inferiorly onto the tongue.
The Palatopharyngeus Muscle
Superior attachment: hard palate and palatine aponeurosis.
Inferior attachment: lateral wall of pharynx.
Innervation: cranial part of accessory nerve (CN XI) through the pharyngeal branch of vagus (CN X) via the pharyngeal plexus.
This thin, flat muscle is covered with mucous membrane to form the palatopharyngeal arch.
It passes posteroinferiorly in this arch.
This muscle tenses the soft palate and pulls the walls of the pharynx superiorly, anteriorly and medially during swallowing.
The Musculus Uvulae
Superior attachment: posterior nasal spine and palatine aponeurosis.
Inferior attachment: mucosa of uvula.
Innervation: cranial part of accessory through the pharyngeal branch of vagus, via the pharyngeal plexus.
It passes posteriorly on each side of the median plane and inserts into the mucosa of the uvula.
When the muscle contracts, it shortens the uvula and pulls it superiorly.
Method of Sterilization for common items
General Microbiology
Method of Sterilization for common items
Autoclaving : Animal cages, Sugar tubes, Lab. Coats, Cotton , Filters, Instruments Culture media, Rubber, Gloves , Stopper, Tubing, Slides, Syringe and Wax needles , Test tubes, Enamel metal trays ,Wire baskets, Wood, Tongue depressor, Applicator, Endodontic instruments, Orthodontic pliers , Orthodontic kits, Saliva ejector, Handpieces Cavitron heads, Steel burs, Steel tumbler, Hand instruments
Hot air oven
Beakers, Flasks, Petri dish, Slides, Syringes, Test tubes, Glycerine, Needles ,Oil, Paper Saliva ejector, Matrix Band
Ethylene oxide
Fabric, Bedding, Blanket, Clothing, Matteresses, Pillows, Disposable instruments , Instruments, Blades, Knives, Scalpels, Scissors ,Talcum powder, Books, Cups, plates , Plastics., Flask, Petridish, Tubes, Tubing, Rubber , catheters, Drains, Gloves ,Special items - Bronchoscope, Cystoscope, Heart lung machine
Glutaraldehyde
Orthodontic kits, Orthodontic pliers , Steel burrs, 3 in 1 syringe tips ,Cystoscope ,Endoscope
Filtration
Antibiotics, Serum, Vaccines
Pit and Fissure Sealants
Conservative DentistryPit and Fissure Sealants
Pit and fissure sealants are preventive dental materials applied to the
occlusal surfaces of teeth to prevent caries in the pits and fissures. These
sealants work by filling in the grooves and depressions on the tooth surface,
thereby eliminating the sheltered environment where bacteria can thrive and
cause decay.
Classification
Mitchell and Gordon (1990) classified pit and fissure sealants based on their
composition and properties. While the specific classification details are not
provided in the prompt, sealants can generally be categorized into:
Resin-Based Sealants: These are the most common type,
made from composite resins that provide good adhesion and durability.
Glass Ionomer Sealants: These sealants release fluoride
and bond chemically to the tooth structure, providing additional protection
against caries.
Polyacid-Modified Resin Sealants: These combine
properties of both resin and glass ionomer sealants, offering improved
adhesion and fluoride release.
Requisites of an Efficient Sealant
For a pit and fissure sealant to be effective, it should possess the
following characteristics:
Viscosity: The sealant should be viscous enough to
penetrate deep into pits and fissures.
Adequate Working Time: Sufficient time for application
and manipulation before curing.
Low Sorption and Solubility: The material should have
low water sorption and solubility to maintain its integrity in the oral
environment.
Rapid Cure: Quick curing time to allow for efficient
application and patient comfort.
Good Adhesion: Strong and prolonged adhesion to enamel
to prevent microleakage.
Wear Resistance: The sealant should withstand the
forces of mastication without wearing away.
Minimum Tissue Irritation: The material should be
biocompatible and cause minimal irritation to oral tissues.
Cariostatic Action: Ideally, the sealant should have
properties that inhibit the growth of caries-causing bacteria.
Indications for Use
Pit and fissure sealants are indicated in the following situations:
Newly Erupted Teeth: Particularly primary molars and
permanent premolars and molars that have recently erupted (within the last 4
years).
Open or Sticky Pits and Fissures: Teeth with pits and
fissures that are not well coalesced and may trap food particles.
Stained Pits and Fissures: Teeth with stained pits and
fissures showing minimal decalcification.
Contraindications for Use
Pit and fissure sealants should not be used in the following situations:
No Previous Caries Experience: Teeth that have no
history of caries and have well-coalesced pits and fissures.
Self-Cleansable Pits and Fissures: Wide pits and
fissures that can be effectively cleaned by normal oral hygiene.
Caries-Free for Over 4 Years: Teeth that have been
caries-free for more than 4 years.
Proximal Caries: Presence of caries on proximal
surfaces, either clinically or radiographically.
Partially Erupted Teeth: Teeth that cannot be
adequately isolated during the sealing process.
Key Points for Sealant Application
Age Range for Sealant Application
3-4 Years of Age: Application is recommended for newly
erupted primary molars.
6-7 Years of Age: First permanent molars typically
erupt during this age, making them prime candidates for sealant application.
11-13 Years of Age: Second permanent molars and
premolars should be considered for sealants as they erupt.
Appendicular Skeleton - Lower extremity
AnatomyHip
Constitutes the pelvic girdle
United with the vertebral column
Union of three parts that is marked by a cup shaped cavity (acetabulum) Ilium
• Prominence of the hip
• Superior border is the crest
• Anterosuperior spine-projection at the anterior tip of the crest
• Corresponding projections on the posterior part are the posterosuperior and posteroinferior iliac spines
• Greater sciatic notch-located beneath the posterior part
• Most is a smooth concavity (iliac fossa)
• Posteriorly it is rough and articulates with the sacrum in the formation of the sacroiliac joint
Pubic bone
Anterior part of the innominate bone
Symphysis pubic-joining of the two pubic bones at the midline
Body and two rami
• Body forms one fifth of the acetabulum
• Superior ramis extends from the body to the median plane: superior border forms the pubic crest
• Inferior ramus extends downward and meets with the ischium
• Pubic arch is formed by the inferior rami of both pubic hones
Ischium
Forms the lower and back part of the innominate bone
Body
• Forms two fifths of the accrabulum
• Ischial tuberosiry-supports the body in a sitting position
• Ramus-passes upward to join the inferior ramus of rhe pubis; known as rhe obturator foramen
Pelvis
Fanned by the right and left hip bones, sacrum, and coccyx
Greater pelvis
o Bounded by the ilia and lower lumbar vertebrae
o Gives support to the abdominal viscera
Lesser pelvis
o Brim of the pelvis corresponds to the sacral promontory
o Inferior outlet is bounded by the tip of the coccyx, ischial tuberosities, and inferior rami of the pubic bones
Female pelvis
o Shows adaptations related to functions as a birth canal Wide outlet
o Angle of the pubic arch is obtuse
Male pelvis
o Shows adaptations that contribute to power and speed
o Heart-shaped outlet
o Angle of the pubic arch is acute
Thigh
Femur-longest and strongest bone of the body
Proximal end has a rounded head that articulates with the acetabulum
Constricted portion-the neck
Greater and lesser trochanters
Slightly arched shaft; is concave posteriorly
o Linea aspera-strengthened by this prominent ridge
o Site of attachment for several muscles
Distal end has two condyles separated on the posterior side by the intercondyloid notch
Knee cap
Patella-sesamoid bone
Embedded in the tendon of the quadriceps muscle
Articulates with the femur
Leg
Tibia-medial bone
o Proximal end has two condyles that articulate with the femur
o Triangular shaft
Anterior-shin
Posterior-soleal line
Distal-medial malleolus that articulates with the latus to form the ankle joint
Fibula-lateral bone
o Articulates with the lateral condyle of the tibia but does not enter the knee joint
o Distal end projects as the lateral malleolus
Ankle, foot, and toes
Adapted for supporting weight but similar in structure to the hand
Talus
o Occupies the uppennost and central position in the tarsus
o Distributes the body weight from the tibia above to the other tarsal bones
Calcaneus (heel)-Iocated beneath the talus
Navicular-located in front of the talus on the medial side; articulates with three cuneifonn bones distally
Cuboid-lies along the lateral border of the navicular bone
Metatarsals
o First, second, and third p1etatarsals lie in front of the three cuneifonn bones
o (2) Fourth and fifth metatarsals lie in front of the cuboid bone
Phalanges
o Distal to the metatarsals
o (2) Two in the great toe; three in each of the other four toes .
Longitudinal arches in the foot (2)
o Lateral-fonned by the calcaneus, talus, cuboid, and fourth and fifth metatarsal bones
o Medial-fonned by the calcaneus, talus, navicular, cuneifonn, and first, second, and third metatarsal bones
Transverse arches-formed by the tarsal and metatarsal bones
HISTOLOGIC CHANGES OF THE PULP
Dental Anatomy
HISTOLOGIC CHANGES OF THE PULP
Regressive changes
Pulp decreases in size by the deposition of dentin.
This can be caused by age, attrition, abrasion, operative procedures, etc.
Cellular organelles decrease in number.
Fibrous changes
They are more obvious in injury rather than aging. Occasionally, scarring may also be apparent.
Pulpal stones or denticles
They can be: a)free, b)attached and/or c)embedded. Also they are devided in two groups: true or false. The true stones (denticles) contain dentinal tubules. The false predominate over the the true and are characterized by concentric layers of calcified material.
Diffuse calcifications
Calcified deposits along the collagen fiber bundles or blood vessels may be observed. They are more often in the root canal portion than the coronal area.
Histology of the Cementum
Cementum is a hard connective tissue that derives from ectomesenchyme.
Embryologically, there are two types of cementum:
Primary cementum: It is acellular and develops slowly as the tooth erupts. It covers the coronal 2/3 of the root and consists of intrinsic and extrinsic fibers (PDL).
Secondary cementum: It is formed after the tooth is in occlusion and consists of extrinsic and intrinsic (they derive from cementoblasts) fibers. It covers mainly the root surface.
Functions of Cementum
It protects the dentin (occludes the dentinal tubules)
It provides attachment of the periodontal fibers
It reverses tooth resorption
Cementum is composed of 90% collagen I and III and ground substance.
50% of cementum is mineralized with hydroxyapatite. Thin at the CE junction, thicker apically.
Enzyme Kinetics
Biochemistry
Enzyme Kinetics
Enzymes are protein catalysts that, like all catalysts, speed up the rate of a chemical reaction without being used up in the process. They achieve their effect by temporarily binding to the substrate and, in doing so, lowering the activation energy needed to convert it to a product.
The rate at which an enzyme works is influenced by several factors, e.g.,
the concentration of substrate molecules (the more of them available, the quicker the enzyme molecules collide and bind with them). The concentration of substrate is designated [S] and is expressed in unit of molarity.
the temperature. As the temperature rises, molecular motion - and hence collisions between enzyme and substrate - speed up. But as enzymes are proteins, there is an upper limit beyond which the enzyme becomes denatured and ineffective.
the presence of inhibitors.
competitive inhibitors are molecules that bind to the same site as the substrate - preventing the substrate from binding as they do so - but are not changed by the enzyme.
noncompetitive inhibitors are molecules that bind to some other site on the enzyme reducing its catalytic power.
pH. The conformation of a protein is influenced by pH and as enzyme activity is crucially dependent on its conformation, its activity is likewise affected.
The study of the rate at which an enzyme works is called enzyme kinetics.
Nerve and vascular formation
Dental Anatomy
Nerve and vascular formation
Frequently, nerves and blood vessels run parallel to each other in the body, and the formation of both usually takes place simultaneously and in a similar fashion. However, this is not the case for nerves and blood vessels around the tooth, because of different rates of development.
Nerve formation
Nerve fibers start to near the tooth during the cap stage of tooth development and grow toward the dental follicle. Once there, the nerves develop around the tooth bud and enter the dental papilla when dentin formation has begun. Nerves never proliferate into the enamel organ
Vascular formation
Blood vessels grow in the dental follicle and enter the dental papilla in the cap stage. Groups of blood vessels form at the entrance of the dental papilla. The number of blood vessels reaches a maximum at the beginning of the crown stage, and the dental papilla eventually forms in the pulp of a tooth. Throughout life, the amount of pulpal tissue in a tooth decreases, which means that the blood supply to the tooth decreases with age. The enamel organ is devoid of blood vessels because of its epithelial origin, and the mineralized tissues of enamel and dentin do not need nutrients from the blood.