NEET MDS Synopsis
ECG FINDINGS
Physiology
1. Hypothermia → Elevation of the j-point — Osborne wave.
2. Hyperkalemia → peaking (tenting) of T-wave, ↓-P-wave amplitude, widening of the QRS interval, cardiac arrest with sine wave (in severe Hyper kalemia)
3. Hypokalemia → Prominent ‘U’-wave, prolongation of ‘QT’ interval.
4. Hypocalcemia → Prolong QT interval
5. Hyper calcemia — Short QT interval.
6. Digitalis toxicity — short QT interval with “scooping” of the ST-T wave comples (i.e. Depression of ST-T segment)
7. Sub arachnoid Hemorrhage→ “CVAT-wave” pattern → marked QT prolongation with deep wide T-wave inversions
8. M.I → T-wave inversion
Nursing Caries and Rampant Caries
Conservative DentistryNursing Caries and Rampant Caries
Nursing caries and rampant caries are both forms of dental caries that can
lead to significant oral health issues, particularly in children.
Nursing Caries
Nursing Caries: A specific form of rampant caries that
primarily affects infants and toddlers, characterized by a distinct pattern
of decay.
Age of Occurrence
Age Group: Typically seen in infants and toddlers,
particularly those who are bottle-fed or breastfed on demand.
Dentition Involved
Affected Teeth: Primarily affects the primary
dentition, especially the maxillary incisors and molars. Notably, the
mandibular incisors are usually spared.
Characteristic Features
Decay Pattern:
Involves maxillary incisors first, followed by molars.
Mandibular incisors are not affected due to protective factors.
Rapid Lesion Development: New lesions appear quickly,
indicating acute decay rather than chronic neglect.
Etiology
Feeding Practices:
Improper feeding practices are the primary cause, including:
Bottle feeding before sleep.
Pacifiers dipped in honey or other sweeteners.
Prolonged at-will breastfeeding.
Treatment
Early Detection: If detected early, nursing caries can
be managed with:
Topical fluoride applications.
Education for parents on proper feeding and oral hygiene.
Maintenance: Focus on maintaining teeth until the
transition to permanent dentition occurs.
Prevention
Education: Emphasis on educating prospective and new
mothers about proper feeding practices and oral hygiene to prevent nursing
caries.
Rampant Caries
Rampant Caries: A more generalized and acute form of
caries that can occur at any age, characterized by widespread decay and
early pulpal involvement.
Age of Occurrence
Age Group: Can be seen at all ages, including
adolescence and adulthood.
Dentition Involved
Affected Teeth: Affects both primary and permanent
dentition, including teeth that are typically resistant to decay.
Characteristic Features
Decay Pattern:
Involves surfaces that are usually immune to decay, including
mandibular incisors.
Rapid appearance of new lesions, indicating a more aggressive form
of caries.
Etiology
Multifactorial Causes: Rampant caries is influenced by
a combination of factors, including:
Frequent snacking and excessive intake of sticky refined
carbohydrates.
Decreased salivary flow.
Genetic predisposition.
Treatment
Pulp Therapy:
Often requires more extensive treatment, including pulp therapy for
teeth with multiple pulp exposures.
Long-term treatment may be necessary, especially when permanent
dentition is involved.
Prevention
Mass Education: Dental health education should be
provided at a community level, targeting individuals of all ages to promote
good oral hygiene and dietary practices.
Key Differences
Mandibular Anterior Teeth
Nursing Caries: Mandibular incisors are spared due to:
Protection from the tongue.
Cleaning action of saliva, aided by the proximity of the sublingual
gland ducts.
Rampant Caries: Mandibular incisors can be affected, as
this condition does not spare teeth that are typically resistant to decay.
Crocodile Tear Syndrome
Oral and Maxillofacial SurgeryCrocodile Tear Syndrome, also known as Bogorad syndrome, is characterized by
involuntary tearing while eating, often resulting from facial nerve damage, such
as that caused by Bell's palsy or trauma. Treatment typically involves botulinum
toxin injections into the lacrimal glands to alleviate symptoms. ### Overview of
Crocodile Tear Syndrome
Crocodile Tear Syndrome is a condition where individuals experience excessive
tearing while eating or drinking. This phenomenon occurs due to misdirection of
nerve fibers from the facial nerve, particularly affecting the lacrimal gland.
Causes
Facial Nerve Injury: Damage to the facial nerve,
especially proximal to the geniculate ganglion, can lead to abnormal nerve
regeneration.
Misdirection of Nerve Fibers: Instead of innervating
the submandibular gland, the nerve fibers may mistakenly connect to the
lacrimal gland via the greater petrosal nerve.
Symptoms
Paroxysmal Lacrimation: Patients experience tearing
during meals, which can be distressing and socially embarrassing.
Associated Conditions: Often seen in individuals
recovering from Bell's palsy or other facial nerve injuries.
Treatment Options
Surgical Intervention: Division of the greater petrosal
nerve can be performed to alleviate symptoms by preventing the misdirected
signals to the lacrimal gland.
Botulinum Toxin Injections: Administering botulinum
toxin into the lacrimal glands can help reduce excessive tearing by
temporarily paralyzing the gland.
Distraction Techniques
PedodonticsDistraction Techniques in Pediatric Dentistry
Distraction is a valuable technique used in pediatric dentistry to help
manage children's anxiety and discomfort during dental procedures. By diverting
the child's attention away from the procedure, dental professionals can create a
more positive experience and reduce the perception of pain or discomfort.
Purpose of Distraction
Divert Attention: The primary goal of distraction is to
shift the child's focus away from the dental procedure, which may be
perceived as unpleasant or frightening.
Reduce Anxiety: Distraction can help alleviate anxiety
and fear associated with dental visits, making it easier for children to
cooperate during treatment.
Enhance Comfort: Providing a break or a moment of
distraction during stressful procedures can enhance the overall comfort of
the child.
Techniques for Distraction
Storytelling:
Engaging the child in a story can capture their attention and
transport them mentally away from the dental environment.
Stories can be tailored to the child's interests, making them more
effective.
Counting Teeth:
Counting the number of teeth loudly can serve as a fun and
interactive way to keep the child engaged.
This technique can also help familiarize the child with the dental
procedure.
Repetitive Statements of Encouragement:
Providing continuous verbal encouragement can help reassure the
child and keep them focused on positive outcomes.
Phrases like "You're doing great!" or "Just a little longer!" can be
effective.
Favorite Jokes or Movies:
Asking the child to recall a favorite joke or movie can create a
light-hearted atmosphere and distract them from the procedure.
This technique can also foster a sense of connection between the
dentist and the child.
Audio-Visual Aids:
Utilizing videos, cartoons, or music can provide a visual and
auditory distraction that captures the child's attention.
Headphones with calming music or engaging videos can be particularly
effective during procedures like local anesthetic administration.
Application in Dental Procedures
Local Anesthetic Administration: Distraction techniques
can be especially useful during the administration of local anesthetics,
which may cause discomfort. Engaging the child in conversation or using
visual aids can help minimize their focus on the injection.
DIURETICS
Pharmacology
DIURETICS
Specific Therapeutic Objective
Clinical State(s)
Drug(s) (Class)
Draw fluid from tissue to vascular space reduce tissue edema
Cerebral edema
glaucoma
Mannitol (Osmotic)
Glucose (Osmotic)
Glycerin (Osmotic)
Decrease renal swelling
expand tubular volume
Renal shutdown
Glucose (Osmotic)
Mannitol (Osmotic)
Modest and/or sustained decrease in venous hydrostatic pressure
Congestive heart failure
Hepatic cirrhosis
Udder edema
Hydrochlorothiazide (thiazide)
Chlorothiazide (thiazide)
Aggressive and/or short-term decrease in venous hydrostatic pressure
Congestive heart failure
Hepatic cirrhosis
Udder edema
Furosemide (loop)
Inhibit aldosterone action
Hepatic cirrhosis
Congestive heart failure
triamterene (K+ sparing)
spironolactone (K+ sparing - competitive)
Reduce potassium wasting 2o to other diuretic
Hepatic cirrhosis
Congestive heart failure
triamterene (K+ sparing)
spironolactone (K+ sparing - competitive)
Inhibit ADH action
Inappropriate ADH secretion
lithium (aquaretic)
demeclocycline (aquaretic
Increase calcium secretion
Malignant hypercalcemia
Paraneoplastic
Hypervitaminosis D
Furosemide (loop)
Reduce urine output
Diabetes insidpidus
Hydrochlorothiazide (thiazide)
Chlorothiazide (thiazide)
Urine alkalinization
Various
Carbonic anhydrase inhibitors
ATROPHY
General Pathology
ATROPHY
It is the acquired decrease in the size of an organ due to decrease in the size and/or number of its constituent cells.
Causes:
(1) Physiological
- Foetal involution.
o Branchial clefts.
o Ductus arterious.
- Involution of thymus and other lymphoid organs in childhood and adolescence.
- In adults:
o Post-partum uterus.
o Post-menopausal ovaries and uterus
o Post-lactational breast
o Thymus.
(2) Pathological:
- Generalised as in
o Ageing.
o Severe starvation and cachexia
- Localised :
o Disuse atropy of bone and muscle.
o Ischaemic atrophy as in arteriosclerotic kidney. .
o Pressure atrophy due to tumours and of kidney in hydronephrosis.
o Lack of trophic stimulus to endocrines and gonads.
Osteoporosis
General Pathology
Osteoporosis
is characterized by increased porosity of the skeleton resulting from reduced bone mass. The disorder may be localized to a certain bone (s), as in disuse osteoporosis of a limb, or generalized involving the entire skeleton. Generalized osteoporosis may be primary, or secondary
Primary generalized osteoporosis
• Postmenopausal
• Senile
Secondary generalized osteoporosis
A. Endocrine disorders
• Hyperparathyroidism
• Hypo or hyperthyroidism
• Others
B. Neoplasia
• Multiple myeloma
• Carcinomatosis
C. Gastrointestinal disorders
• Malnutrition & malabsorption
• Vit D & C deficiency
• Hepatic insufficiency
D. Drugs
• Corticosteroids
• Anticoagulants
• Chemotherapy
• Alcohol
E. Miscellaneous
• osteogenesis imperfecta
• immobilization
• pulmonary disease
Senile and postmenopausal osteoporosis are the most common forms. In the fourth decade in both sexes, bone resorption begins to overrun bone deposition. Such losses generally occur in areas containing abundant cancelloues bone such as the vertebrae & femoral neck. The postmenopausal state accelerates the rate of loss; that is why females are more susceptible to osteoporosis and its complications.
Gross features
• Because of bone loss, the bony trabeculae are thinner and more widely separated than usual. This leads to obvious porosity of otherwise spongy cancellous bones
Microscopic features
• There is thinning of the trabeculae and widening of Haversian canals.
• The mineral content of the thinned bone is normal, and thus there is no alteration in the ratio of minerals to protein matrix
Etiology & Pathogenesis
• Osteoporosis involves an imbalance of bone formation, bone resorption, & regulation of osteoclast activation. It occurs when the balance tilts in favor of resorption.
• Osteoclasts (as macrophages) bear receptors (called RANK receptors) that when stimulated activate the nuclear factor (NFκB) transcriptional pathway. RANK ligand synthesized by bone stromal cells and osteoblasts activates RANK. RANK activation converts macrophages into bone-crunching osteoclasts and is therefore a major stimulus for bone resorption.
• Osteoprotegerin (OPG) is a receptor secreted by osteoblasts and stromal cells, which can bind RANK ligand and by doing so makes the ligand unavailable to activate RANK, thus limiting osteoclast bone-resorbing activity.
• Dysregulation of RANK, RANK ligand, and OPG interactions seems to be a major contributor in the pathogenesis of osteoporosis. Such dysregulation can occur for a variety of reasons, including aging and estrogen deficiency.
• Influence of age: with increasing age, osteoblasts synthetic activity of bone matrix progressively diminished in the face of fully active osteoclasts.
• The hypoestrogenic effects: the decline in estrogen levels associated with menopause correlates with an annual decline of as much as 2% of cortical bone and 9% of cancellous bone. The hypoestrogenic effects are attributable in part to augmented cytokine production (especially interleukin-1 and TNF). These translate into increased RANK-RANK ligand activity and diminished OPG.
• Physical activity: reduced physical activity increases bone loss. This effect is obvious in an immobilized limb, but also occurs diffusely with decreased physical activity in older individuals.
• Genetic factors: these influence vitamin D receptors efficiency, calcium uptake, or PTH synthesis and responses.
• Calcium nutritional insufficiency: the majority of adolescent girls (but not boys) have insufficient dietary intake of calcium. As a result, they do not achieve the maximal peak bone mass, and are therefore likely to develop clinically significant osteoporosis at an earlier age.
• Secondary causes of osteoporosis: these include prolonged glucocorticoid therapy (increases bone resorption and reduce bone synthesis.)
The clinical outcome of osteoporosis depends on which bones are involved. Thoracic and lumbar vertebral fractures are extremely common, and produce loss of height and various deformities, including kyphoscoliosis that can compromise respiratory function. Pulmonary embolism and pneumonia are common complications of fractures of the femoral neck, pelvis, or spine.
RESPIRATORY DISORDERS - Bronchitis
Physiology
Bronchitis = Irreversible Bronchioconstriction
. Causes - Infection, Air polution, cigarette smoke
a. Primary Defect = Enlargement & Over Activity of Mucous Glands, Secretions very viscous
b. Hypertrophy & hyperplasia, Narrows & Blocks bronchi, Lumen of airway, significantly narrow
c. Impaired Clearance by mucocillary elevator
d. Microorganism retension in lower airways,Prone to Infectious Bronchitis, Pneumonia
e. Permanent Inflamatory Changes IN epithelium, Narrows walls, Symptoms, Excessive sputum, coughing
f. CAN CAUSE EMPHYSEMA