NEET MDS Synopsis
Classification for antiasthmatic drugs.
Pharmacology
ANTIASTHMATIC AGENTS
Classification for antiasthmatic drugs.
I. Bronchodilators
i. Sympathomimetics (adrenergic receptor agonists)
Adrenaline, ephedrine, isoprenaline, orciprenaline, salbutamol, terbutaline, salmeterol, bambuterol
ii. Methylxanthines (theophylline and its derivatives)
Theophylline
Hydroxyethyl theophylline
Theophylline ethanolate of piperazine
iii. Anticholinergics
Atropine methonitrate
Ipratropium bromide
II. Mast cell stabilizer
Sodium cromoglycate
Ketotifen
III. Corticosteroids
Beclomethasone dipropionate
Beclomethasone (200 µg) with salbutamol
IV. Leukotriene pathway inhibitors
Montelukast
Zafirlukast
Classification of Cerebral Palsy
PedodonticsClassification of Cerebral Palsy
Cerebral palsy (CP) is a group of neurological disorders that affect
movement, muscle tone, and motor skills. The classification of cerebral palsy is
primarily based on the type of neuromuscular dysfunction observed in affected
individuals. Below is an outline of the main types of cerebral palsy, along with
their basic characteristics.
1. Spastic Cerebral Palsy (Approximately 70% of Cases)
Definition: Characterized by hypertonicity (increased
muscle tone) and exaggerated reflexes.
Characteristics:
A. Hyperirritability of Muscles: Involved muscles
exhibit exaggerated contractions when stimulated.
B. Tense, Contracted Muscles:
Example: Spastic Hemiplegia affects one side of
the body, with the affected hand and arm flexed against the trunk.
The leg may be flexed and internally rotated, leading to a limping
gait with circumduction of the affected leg.
C. Limited Neck Control: Difficulty controlling
neck muscles results in head rolling.
D. Trunk Muscle Control: Lack of control in trunk
muscles leads to difficulties in maintaining an upright posture.
E. Coordination Issues: Impaired coordination of
intraoral, perioral, and masticatory muscles can result in:
Impaired chewing and swallowing
Excessive drooling
Persistent spastic tongue thrust
Speech impairments
2. Dyskinetic Cerebral Palsy (Athetosis and Choreoathetosis) (Approximately
15% of Cases)
Definition: Characterized by constant and uncontrolled
movements.
Characteristics:
A. Uncontrolled Motion: Involved muscles exhibit
constant, uncontrolled movements.
B. Athetoid Movements: Slow, twisting, or writhing
involuntary movements (athetosis) or quick, jerky movements
(choreoathetosis).
C. Neck Muscle Involvement: Excessive head movement
due to hypertonicity of neck muscles, which may cause the head to be
held back, with the mouth open and tongue protruded.
D. Jaw Involvement: Frequent uncontrolled jaw
movements or severe bruxism (teeth grinding).
E. Hypotonicity of Perioral Musculature:
Symptoms include mouth breathing, tongue protrusion, and
excessive drooling.
F. Facial Grimacing: Involuntary facial expressions
may occur.
G. Chewing and Swallowing Difficulties: Challenges
in these areas are common.
H. Speech Problems: Communication difficulties may
arise.
3. Ataxic Cerebral Palsy (Approximately 5% of Cases)
Definition: Characterized by poor coordination and
balance.
Characteristics:
A. Incomplete Muscle Contraction: Involved muscles
do not contract completely, leading to partial voluntary movements.
B. Poor Balance and Coordination: Individuals may
exhibit a staggering or stumbling gait and difficulty grasping objects.
C. Tremors: Possible tremors or uncontrollable
trembling when attempting voluntary tasks.
4. Mixed Cerebral Palsy (Approximately 10% of Cases)
Definition: A combination of characteristics from more
than one type of cerebral palsy.
Example: Mixed spastic-athetoid quadriplegia, where
features of both spastic and dyskinetic types are present.
Classification of cysts of the orofacial region
Oral Pathology
Epithelial cysts
Developmental odontogenic cysts
Odontogenic keratocyst
Dentigerous cyst (follicular cyst)
Eruption cyst
Lateral periodontal cyst
Gingival cyst of adults
Glandular odontogenic cyst (sialo-odontogenic)
Inflammatory odontogenic cysts
Radicular cyst (apical and lateral)
Residual cyst
Paradental cyst
Non-odontogenic cysts
Nasopalatine cyst
Nasolabial cyst
Non-epithelial cysts (not true cysts)
Solitary bone cyst
Aneurysmal bone cyst
Structure and function of skeletal muscle
PhysiologyStructure and function of skeletal muscle.
Skeletal muscles have a belly which contains the cells and which attaches by means of tendons or aponeuroses to a bone or other tissue. An aponeurosis is a broad, flat, tendinous attachment, usually along the edge of a muscle. A muscle attaches to an origin and an insertion. The origin is the more fixed attachment, the insertion is the more movable attachment. A muscle acts to shorten, pulling the insertion toward the origin. A muscle can only pull, it cannot push.
Muscles usually come in pairs of antagonistic muscles. The muscle performing the prime movement is the agonist, the opposite acting muscle is the antagonist. When the movement reverses, the names reverse. For example, in flexing the elbow the biceps brachii is the agonist, the triceps brachii is the antagonist. When the movement changes to extension of the elbow, the triceps becomes the agonist and the biceps the antagonist. An antagonist is never totally relaxed. Its function is to provide control and damping of movement by maintaining tone against the agonist. This is called eccentric movement.
Muscles can also act as synergists, working together to perform a movement. This movement can be different from that performed when the muscles work independently. For example, the sternocleidomastoid muscles each rotate the head in a different direction. But as synergists they flex the neck.
Fixators act to keep a part from moving. For example fixators act as postural muscles to keep the spine erect and the leg and vertebral column extended when standing. Fixators such as the rhomboids and levator scapulae keep the scapula from moving during actions such as lifting with the arms.
APPLICATIONS OF LASERS IN ENDODONTICS
Endodontics
I. VASCULAR VITALITY ASSESSMENT OF PULP
Traditional vitality assessment methods such as heat, cold, and electric pulp testers assess neural vitality and often cause false-positive
errors. As the histological assessment of pulpal status is not feasible clinically, a tool to assess the vascular flow of the pulp would be
very useful.
Laser Doppler flowmetry (LDF) is an accurate method to assess the blood flow in a microvascular
system
II. PULP CAPPING AND PULPOTOMY
Pulp capping and pulpotomy constitute a more conservative form of pulp therapy in comparison to pulpectomy. Although the outcome
of pulp capping procedure is variable ranging from 44 to 97%, the procedure is recommended when the exposure is 1.0 mm or less
and especially when the patient is young. Pulpotomy is recommended in immature permanent teeth, where pulpectomy is not advised.
The most commonly used agents for both the procedures are calcium hydroxide and MTA (mineral trioxide aggregate). The use of a
laser in these procedures leads to a potentially bloodless field as the laser has the ability to coagulate and seal small blood vessels. The
laser-tissue interactions make the treated wound surface sterile and also improve the prognosis of the procedure.
III. DISINFECTION OF ROOT CANALS
The ability of bacterial pathogens to persist after shaping and cleaning is one of the main reasons for endodontic failures. This is
attributed to the complex nature of the root canal system, the presence of a smear layer, and the fact that large areas (over 35%) of the
canal surface area remain unchanged following instrumentation with various Ni-Ti techniques.
IV. OBTURATION
Thermoplasticized gutta-percha obturation systems are one of the most efficient methods is achieving a fluid-impervious seal.
Softening of the gutta-percha has been attempted with various lasers. These include argon, CO
, Nd:YAG, and Er:YAG.
V.APICAL SURGERY
Apical surgery including apical resection is indicated when the previously performed root canal therapy fails and nonsurgical means
are inadequate to ensure the complete removal of the pathological process.
The potential for using lasers is on the basis of the following observations:
• Ability of lasers to coagulate and seal small blood vessels, thereby enabling a bloodless surgical field
• Sterilization of the surgical site
• Potential of lasers (Er:YAG) to cut hard dental tissues without causing elaborate thermal damage to the adjoining tissues .
Epoxy Resin Sealers Composition in Endodontics
EndodonticsEpoxy resin sealers are widely used in endodontics due to their favorable
properties, including excellent sealing ability, biocompatibility, and
resistance to washout. Understanding their composition is crucial for dental
professionals to select the appropriate materials for root canal treatments.
Here’s a detailed overview of the composition of epoxy resin sealers used in
endodontics.
Key Components of Epoxy Resin Sealers
Base Component
Polyepoxy Resins:
The primary component that provides the sealing properties. These
resins are known for their strong adhesive qualities and dimensional
stability.
Commonly used polyepoxy resins include diglycidyl ether of bisphenol
A (DGEBA).
Curing Agent
Amine-Based Curing Agents:
These agents initiate the curing process of the epoxy resin, leading
to the hardening of the material.
Examples include triethanolamine (TEA) and other amine compounds
that facilitate cross-linking of the resin.
Fillers
Inorganic Fillers:
Materials such as zirconium oxide and calcium oxide are often added
to enhance the physical properties of the sealer, including
radiopacity and strength.
Fillers can also improve the flowability of the sealer, allowing it
to fill irregularities in the canal system effectively.
Plasticizers
Additives:
Plasticizers may be included to improve the flexibility and
workability of the sealer, making it easier to manipulate during
application.
Antimicrobial Agents
Incorporated Compounds:
Some epoxy resin sealers may contain antimicrobial agents to help
reduce bacterial load within the root canal system, promoting
healing and preventing reinfection.
Examples of Epoxy Resin Sealers
AH-Plus
Composition:
Contains a polyepoxy resin base, amine curing agents, and inorganic
fillers.
Properties:
Known for its excellent sealing ability, low solubility, and good
adhesion to dentin.
AD Seal
Composition:
Similar to AH-Plus, with a focus on enhancing flowability and
reducing cytotoxicity.
Properties:
Offers good sealing properties and is used in various clinical
situations.
EndoSeal MTA
Composition:
Combines epoxy resin with bioceramic materials, providing additional
benefits such as bioactivity and improved sealing.
Properties:
Known for its favorable physicochemical properties and
biocompatibility.
Clinical Implications
Selection of Sealers: The choice of epoxy resin sealer should be
based on the specific clinical situation, considering factors such as the
complexity of the canal system, the need for antimicrobial properties, and
the desired setting time.
Application Techniques: Proper mixing and application techniques
are essential to ensure optimal performance of the sealer, including
achieving a fluid-tight seal and preventing voids.
Conclusion
Epoxy resin sealers are composed of a combination of polyepoxy resins, curing
agents, fillers, and additives that contribute to their effectiveness in
endodontic treatments. Understanding the composition and properties of these
sealers allows dental professionals to make informed decisions, ultimately
enhancing the success of root canal therapy.
Here are some notable epoxy resin sealers used in endodontics, along with their
key features:
1. AH
Plus
Description: A widely used epoxy resin-based root canal sealer.
Properties:
Excellent sealing ability.
High biocompatibility.
Good adhesion to gutta-percha and dentin.
Uses: Suitable for permanent root canal fillings.
2. Dia-ProSeal
Description: A two-component epoxy resin-based system.
Properties:
Low shrinkage and high adhesion.
Outstanding flow characteristics.
Antimicrobial activity due to the addition of calcium hydroxide.
Uses: Effective for sealing lateral canals and suitable for warm
gutta-percha techniques.
3. Vioseal
Description: An epoxy resin-based root canal sealer available in a
dual syringe format.
Properties:
Good flowability and sealing properties.
Radiopaque for easy identification on radiographs.
Uses: Used for permanent root canal fillings.
4. AH
Plus Jet
Description: A variant of AH Plus that features an auto-mixing
system.
Properties:
Consistent mixing and application.
Excellent sealing and adhesion properties.
Uses: Ideal for various endodontic applications.
5. EndoREZ
Description: A resin-based sealer that combines epoxy and
methacrylate components.
Properties:
High bond strength and low solubility.
Good flow and adaptability to canal irregularities.
Uses: Suitable for permanent root canal fillings, especially in
complex canal systems.
6. Resilon
Description: A thermoplastic synthetic polymer-based root canal
filling material that can be used with epoxy resin sealers.
Properties:
Provides a monoblock effect with the sealer.
Excellent sealing ability and biocompatibility.
Uses: Used in conjunction with epoxy resin sealers for enhanced
sealing.
Conclusion
Epoxy resin sealers are essential in endodontics for achieving effective and
durable root canal fillings. The choice of sealer may depend on the specific
clinical situation, the complexity of the canal system, and the desired
properties for optimal sealing and biocompatibility.
Dental Calculus
Periodontology
Dental Calculus
Dental calculus, also known as tartar, is a hard deposit that forms on teeth
due to the mineralization of dental plaque. Understanding the composition and
crystal forms of calculus is essential for dental professionals in diagnosing
and managing periodontal disease.
Crystal Forms in Dental Calculus
Common Crystal Forms:
Dental calculus typically contains two or more crystal forms. The
most frequently detected forms include:
Hydroxyapatite:
This is the primary mineral component of both enamel and
calculus, constituting a significant portion of the calculus
sample.
Hydroxyapatite is a crystalline structure that provides
strength and stability to the calculus.
Octacalcium Phosphate:
Detected in a high percentage of supragingival calculus
samples (97% to 100%).
This form is also a significant contributor to the bulk of
calculus.
Other Crystal Forms:
Brushite:
More commonly found in the mandibular anterior region of the
mouth.
Brushite is a less stable form of calcium phosphate and may
indicate a younger calculus deposit.
Magnesium Whitlockite:
Typically found in the posterior areas of the mouth.
This form may be associated with older calculus deposits and can
indicate changes in the mineral composition over time.
Variation with Age:
The incidence and types of crystal forms present in calculus can
vary with the age of the deposit.
Younger calculus deposits may have a higher proportion of brushite,
while older deposits may show a predominance of hydroxyapatite and
magnesium whitlockite.
Clinical Significance
Understanding Calculus Formation:
Knowledge of the crystal forms in calculus can help dental
professionals understand the mineralization process and the conditions
under which calculus forms.
Implications for Treatment:
The composition of calculus can influence treatment strategies. For
example, older calculus deposits may be more difficult to remove due to
their hardness and mineral content.
Assessment of Periodontal Health:
The presence and type of calculus can provide insights into a
patient’s oral hygiene practices and periodontal health. Regular
monitoring and removal of calculus are essential for preventing
periodontal disease.
Research and Development:
Understanding the mineral composition of calculus can aid in the
development of new dental materials and treatments aimed at preventing
calculus formation and promoting oral health.
Zygomatic Bone Reduction
General SurgeryZygomatic Bone Reduction
When performing a reduction of the zygomatic bone, particularly in the
context of maxillary arch fractures, several key checkpoints are used to assess
the success of the procedure. Here’s a detailed overview of the important
checkpoints for both zygomatic bone and zygomatic arch reduction.
Zygomatic Bone Reduction
Alignment at the Sphenozygomatic Suture:
While this is considered the best checkpoint for assessing the
reduction of the zygomatic bone, it may not always be the most practical
or available option in certain clinical scenarios.
Symmetry of the Zygomatic Arch:
Importance: This is the second-best checkpoint and
serves multiple purposes:
Maintains Interzygomatic Distance: Ensures that
the distance between the zygomatic bones is preserved, which is
crucial for facial symmetry.
Maintains Facial Symmetry and Aesthetic Balance:
A symmetrical zygomatic arch contributes to the overall aesthetic
appearance of the face.
Preserves the Dome Effect: The prominence of
the zygomatic arch creates a natural contour that is important for
facial aesthetics.
Continuity of the Infraorbital Rim:
A critical checkpoint indicating that the reduction is complete. The
infraorbital rim should show no step-off, indicating proper alignment
and continuity.
Continuity at the Frontozygomatic Suture:
Ensures that the junction between the frontal bone and the zygomatic
bone is intact and properly aligned.
Continuity at the Zygomatic Buttress Region:
The zygomatic buttress is an important structural component that
provides support and stability to the zygomatic bone.
Zygomatic Arch Reduction
Click Sound:
The presence of a click sound during manipulation can indicate
proper alignment and reduction of the zygomatic arch.
Symmetry of the Arches:
Assessing the symmetry of the zygomatic arches on both sides of the
face is crucial for ensuring that the reduction has been successful and
that the facial aesthetics are preserved.