NEET MDS Synopsis
MAXILLARY FIRST BICUSPID
Dental Anatomy
MAXILLARY FIRST BICUSPID (PREMOLARS)
It is considered to be the typical bicuspid. (The word "bicuspid" means "having two cusps.")
Facial: The buccal surface is quite rounded and this tooth resembles the maxillary canine. The buccal cusp is long; from that cusp tip, the prominent buccal ridge descends to the cervical line of the tooth.
Lingual: The lingual cusp is smaller and the tip of that cusp is shifted toward the mesial. The lingual surface is rounded in all aspects.
Proximal: The mesial aspect of this tooth has a distinctive concavity in the cervical third that extends onto the root. It is called variously the mesial developmental depression, mesial concavity, or the 'canine fossa'--a misleading description since it is on the premolar. The distal aspect of the maxillary first permanent molar also has a developmental depression. The mesial marginal developmental groove is a distinctive feature of this tooth.
Occlusal: There are two well-defined cusps buccal and lingual. The larger cusp is the buccal; its cusp tip is located midway mesiodistally. The lingual cusp tip is shifted mesially. The occlusal outline presents a hexagonal appearance. On the mesial marginal ridge is a distinctive feature, the mesial marginal developmental groove.
Contact Points;The distal contact area is located more buccal than is the mesial contact area.
Root Surface:-The root is quite flat on the mesial and distal surfaces. In about 50 percent of maxillary first bicuspids, the root is divided in the apical third, and when it so divided, the tips of the facial and lingual roots are slender and finely tapered.
Nimesulide
Pharmacology
Nimesulide
analgesic and antipyretic properties
Nimesulide is a relatively COX-2 selective, non-steroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic properties. Its approved indications are the treatment of acute pain, the symptomatic treatment of osteoarthritis and primary dysmenorrhoea in adolescents and adults above 12 years old.
Banned - not used
CPP-ACP- casein phosphopeptide-amorphous calcium phosphate
Conservative Dentistry
CPP-ACP, or casein phosphopeptide-amorphous calcium phosphate, is a
significant compound in dentistry, particularly in the prevention and management
of dental caries (tooth decay).
Role and applications in dentistry:
Composition and Mechanism
Composition: CPP-ACP is derived from casein, a milk
protein. It contains clusters of calcium and phosphate ions that are
stabilized by casein phosphopeptides.
Mechanism: The unique structure of CPP-ACP allows it to
stabilize calcium and phosphate in a soluble form, which can be delivered to
the tooth surface. When applied to the teeth, CPP-ACP can release these
ions, promoting the remineralization of enamel and dentin, especially in
early carious lesions.
Benefits in Dentistry
Remineralization: CPP-ACP helps in the remineralization
of demineralized enamel, making it an effective treatment for early carious
lesions.
Caries Prevention: Regular use of CPP-ACP can help
prevent the development of caries by maintaining a higher concentration of
calcium and phosphate in the oral environment.
Reduction of Sensitivity: It can help reduce tooth
sensitivity by occluding dentinal tubules and providing a protective layer
over exposed dentin.
pH Buffering: CPP-ACP can help buffer the pH in the
oral cavity, reducing the risk of acid-induced demineralization.
Compatibility with Fluoride: CPP-ACP can be used in
conjunction with fluoride, enhancing the overall effectiveness of caries
prevention strategies.
Applications
Toothpaste: Some toothpaste formulations include
CPP-ACP to enhance remineralization and provide additional protection
against caries.
Chewing Gum: Sucrose-free chewing gums containing
CPP-ACP can be used to promote oral health, especially after meals.
Dental Products: CPP-ACP is also found in various
dental products, including varnishes and gels, used in professional dental
treatments.
Considerations
Lactose Allergy: Since CPP-ACP is derived from milk, it
should be avoided by individuals with lactose intolerance or milk protein
allergies.
Clinical Use: Dentists may recommend CPP-ACP products
for patients at high risk for caries, those with a history of dental decay,
or individuals undergoing orthodontic treatment.
Resistance Form in Dental Restorations
Conservative DentistryResistance Form in Dental Restorations
Resistance form is a critical concept in operative dentistry that refers to
the design features of a cavity preparation that enhance the ability of a
restoration to withstand masticatory forces without failure. This lecture will
cover the key elements that contribute to resistance form, the factors affecting
it, and the implications for different types of restorative materials.
1. Elements of Resistance Form
A. Design Features
Flat Pulpal and Gingival Floors:
Flat surfaces provide stability and help distribute occlusal forces
evenly across the restoration, reducing the risk of displacement.
Box-Shaped Cavity:
A box-shaped preparation enhances resistance by providing a larger
surface area for bonding and mechanical retention.
Inclusion of Weakened Tooth Structure:
Including weakened areas in the preparation helps to prevent
fracture under masticatory forces by redistributing stress.
Rounded Internal Line Angles:
Rounding internal line angles reduces stress concentration points,
which can lead to failure of the restoration.
Adequate Thickness of Restorative Material:
Sufficient thickness is necessary to ensure that the restoration can
withstand occlusal forces without fracturing. The required thickness
varies depending on the type of restorative material used.
Cusp Reduction for Capping:
When indicated, reducing cusps helps to provide adequate support for
the restoration and prevents fracture.
B. Deepening of Pulpal Floor
Increased Bulk: Deepening the pulpal floor increases
the bulk of the restoration, enhancing its resistance to occlusal forces.
2. Features of Resistance Form
A. Box-Shaped Preparation
A box-shaped cavity preparation is essential for providing resistance
against displacement and fracture.
B. Flat Pulpal and Gingival Floors
These features help the tooth resist occlusal masticatory forces without
displacement.
C. Adequate Thickness of Restorative Material
The thickness of the restorative material should be sufficient to
prevent fracture of both the remaining tooth structure and the restoration.
For example:
High Copper Amalgam: Minimum thickness of 1.5 mm.
Cast Metal: Minimum thickness of 1.0 mm.
Porcelain: Minimum thickness of 2.0 mm.
Composite and Glass Ionomer: Typically require
thicknesses greater than 2.5 mm due to their wear potential.
D. Restriction of External Wall Extensions
Limiting the extensions of external walls helps maintain strong marginal
ridge areas with adequate dentin support.
E. Rounding of Internal Line Angles
This feature reduces stress concentration points, enhancing the overall
resistance form.
F. Consideration for Cusp Capping
Depending on the amount of remaining tooth structure, cusp capping may
be necessary to provide adequate support for the restoration.
3. Factors Affecting Resistance Form
A. Amount of Occlusal Stresses
The greater the occlusal forces, the more robust the resistance form
must be to prevent failure.
B. Type of Restoration Used
Different materials have varying requirements for thickness and design
to ensure adequate resistance.
C. Amount of Remaining Tooth Structure
The more remaining tooth structure, the better the support for the
restoration, which can enhance resistance form.
4. Clinical Implications
A. Cavity Preparation
Proper cavity preparation is essential for achieving optimal resistance
form. Dentists should consider the design features and material requirements
when preparing cavities.
B. Material Selection
Understanding the properties of different restorative materials is
crucial for ensuring that the restoration can withstand the forces it will
encounter in the oral environment.
C. Monitoring and Maintenance
Regular monitoring of restorations is important to identify any signs of
failure or degradation, allowing for timely intervention.
TCI -Target Controlled Infusion
Pharmacology
TCI -Target Controlled Infusion
TCI is an infusion system which allows the anaesthetist to select the target blood concentration required for a particular effect and then to control depth of anaesthesia by adjusting the requested target concentration
Mechanism
Instead of setting ml/h or a dose rate (mg/kg/h), the pump can be programmed to target a required blood concentration.
• Effect site concentration targeting is now included for certain pharmacokinetic models.
• The pump will automatically calculate how much is needed as induction and maintenance to maintain that concentration.
Rocky Mountain Spotted Fever
General Pathology
Rocky Mountain Spotted Fever (Spotted Fever; Tick Fever; Tick Typhus)
An acute febrile disease caused by Rickettsia rickettsii and transmitted by ixodid ticks, producing high fever, cough, and rash.
Symptoms and Signs
The incubation period averages 7 days but varies from 3 to 12 days; the shorter the incubation period, the more severe the infection. Onset is abrupt, with severe headache, chills, prostration, and muscular pains. Fever reaches 39.5 or 40° C (103 or 104° F) within several days and remains high (for 15 to 20 days in severe cases),
Between the 1st and 6th day of fever, most patients develop a rash on the wrists, ankles, palms, soles, and forearms that rapidly extends to the neck, face, axilla, buttocks, and trunk. Often, a warm water or alcohol compress brings out the rash. Initially macular and pink, it becomes maculopapular and darker. In about 4 days, the lesions become petechial and may coalesce to form large hemorrhagic areas that later ulcerate
Neurologic symptoms include headache, restlessness, insomnia, delirium, and coma, all indicative of encephalitis. Hypotension develops in severe cases. Hepatomegaly may be present, but jaundice is infrequent. Localized pneumonitis may occur. Untreated patients may develop pneumonia, tissue necrosis, and circulatory failure, with such sequelae as brain and heart damage. Cardiac arrest with sudden death occasionally occurs in fulminant cases.
Stages of Freud\'s Model
PedodonticsStages of Freud's Model
Oral Stage (1-2 years):
Focus: The mouth is the primary source of
interaction and pleasure. Infants derive satisfaction from oral
activities such as sucking, biting, and chewing.
Developmental Task: The primary task during this
stage is to develop trust and comfort through oral stimulation.
Successful experiences lead to a sense of security.
Example: Sucking on a pacifier or breastfeeding
helps infants develop trust in their caregivers.
Potential Outcomes: Fixation at this stage can lead
to issues with dependency or aggression in adulthood. Individuals may
develop oral-related habits, such as smoking or overeating.
Anal Stage (2-3 years):
Focus: The anal zone becomes the primary source of
pleasure. Children derive gratification from controlling bowel
movements.
Developmental Task: Toilet training is a
significant aspect of this stage. The way parents handle toilet training
can influence personality development.
Outcomes:
Overemphasis on Toilet Training: If parents are
too strict or demanding, the child may develop an anal-retentive
personality, characterized by compulsiveness, orderliness, and
stubbornness.
Lax Toilet Training: If parents are too
lenient, the child may develop an anal-expulsive personality,
leading to impulsiveness and a lack of organization.
Phallic Stage (3-5 years):
Focus: The child becomes aware of their own
genitals and develops sexual feelings. This stage is marked by the
Oedipus complex in boys and the Electra complex in girls.
Oedipus Complex: Boys develop an attraction to
their mother and view their father as a rival for her affection. This
leads to feelings of jealousy and fear of punishment (castration
anxiety).
Electra Complex: Girls experience a similar
attraction to their father and may feel competition with their mother,
leading to "penis envy."
Developmental Task: Resolution of these complexes
is crucial for developing a mature sexual identity and healthy
relationships.
Latency Stage (6 years to puberty):
Focus: Sexual feelings are repressed, and children
focus on developing skills, friendships, and social interactions. This
stage corresponds with the development of mixed dentition (the
transition from primary to permanent teeth).
Developmental Task: The maturation of the ego
occurs, and children develop their character and social skills. They
engage in activities that foster learning and peer relationships.
Potential Outcomes: Successful navigation of this
stage leads to the development of self-confidence and competence in
social settings.
Genital Stage (puberty onward):
Focus: The individual develops a mature sexual
identity and seeks to establish meaningful relationships. The focus is
on the genitals and the ability to engage in sexual activity.
Developmental Task: The individual learns to
balance the needs of the self with the needs of others, leading to the
ability to form healthy, intimate relationships.
Potential Outcomes: Successful resolution of
earlier stages leads to a well-adjusted adult who can satisfy their
sexual and emotional needs while also pursuing goals related to
reproduction and personal identity.
Oedipus Complex: Young boys have a natural tendency to be attached to
the mother and they consider their father as their enemy.
Window of Infectivity
Conservative DentistryWindow of Infectivity
The concept of the "window of infectivity" was introduced by Caufield in 1993
to describe critical periods in early childhood when the oral cavity is
particularly susceptible to colonization by Streptococcus mutans, a key
bacterium associated with dental caries. Understanding these windows is
essential for implementing preventive measures against caries in children.
Window of Infectivity: This term refers to specific
time periods during which the acquisition of Streptococcus mutans occurs,
leading to an increased risk of dental caries. These windows are
characterized by the eruption of teeth, which creates opportunities for
bacterial colonization.
First Window of Infectivity
A. Timing
Age Range: The first window of infectivity is observed
between 19 to 23 months of age, coinciding with the
eruption of primary teeth.
B. Mechanism
Eruption of Primary Teeth: As primary teeth erupt, they
provide a "virgin habitat" for S. mutans to colonize the oral
cavity. This is significant because:
Reduced Competition: The newly erupted teeth have
not yet been colonized by other indigenous bacteria, allowing S.
mutans to establish itself without competition.
Increased Risk of Caries: The presence of S.
mutans in the oral cavity during this period can lead to an
increased risk of developing dental caries, especially if dietary habits
include frequent sugar consumption.
Second Window of Infectivity
A. Timing
Age Range: The second window of infectivity occurs
between 6 to 12 years of age, coinciding with the eruption
of permanent teeth.
B. Mechanism
Eruption of Permanent Dentition: As permanent teeth
emerge, they again provide opportunities for S. mutans to colonize
the oral cavity. This window is characterized by:
Increased Susceptibility: The transition from
primary to permanent dentition can lead to changes in oral flora and an
increased risk of caries if preventive measures are not taken.
Behavioral Factors: During this age range, children
may have increased exposure to sugary foods and beverages, further
enhancing the risk of S. mutans colonization and subsequent
caries development.
4. Clinical Implications
A. Preventive Strategies
Oral Hygiene Education: Parents and caregivers should
be educated about the importance of maintaining good oral hygiene practices
from an early age, especially during the windows of infectivity.
Dietary Counseling: Limiting sugary snacks and
beverages during these critical periods can help reduce the risk of S.
mutans colonization and caries development.
Regular Dental Visits: Early and regular dental
check-ups can help monitor the oral health of children and provide timely
interventions if necessary.
B. Targeted Interventions
Fluoride Treatments: Application of fluoride varnishes
or gels during these windows can help strengthen enamel and reduce the risk
of caries.
Sealants: Dental sealants can be applied to newly
erupted permanent molars to provide a protective barrier against caries.