NEET MDS Synopsis
FLUXING
Dental Materials
FLUXING
To prevent oxidation of gold alloys during melting always use a reducing flux .
Boric acid & borax are used .
Fourth Generation:
Pharmacology
Fourth Generation:
These are extended spectrum antibiotics. They are resistant to beta lactamases.
Cefipime
Dental Mercury Hygiene Recommendations
Conservative DentistryDental mercury hygiene is crucial in minimizing occupational exposure to mercury
vapor and amalgam particles during the placement, removal, and handling of
dental amalgam. The following recommendations are based on the best practices
and guidelines established by various dental and environmental health
organizations:
- Use of amalgam separators: Dental offices should install and
maintain amalgam separators to capture at least 95% of amalgam particles before
they enter the wastewater system. This reduces the release of mercury into the
environment.
- Vacuum line maintenance: Regularly replace the vacuum line
trap to avoid mercury accumulation and ensure efficient evacuation of mercury
vapor during amalgam removal.
- Adequate ventilation: Maintain proper air exchange in the
operatory and use a high-volume evacuation (HVE) system to reduce mercury vapor
levels during amalgam placement and removal.
- Personal protective equipment (PPE): Dentists, hygienists,
and assistants should wear PPE, such as masks, gloves, and protective eyewear to
minimize skin and respiratory exposure to mercury vapor and particles.
- Mercury spill management: Have a written spill protocol and
necessary clean-up materials readily available. Use a HEPA vacuum to clean up
spills and dispose of contaminated materials properly.
- Safe storage: Store elemental mercury in tightly sealed,
non-breakable containers in a dedicated area with controlled access.
- Proper disposal: Follow local, state, and federal regulations
for the disposal of dental amalgam waste, including used capsules, amalgam
separators, and chairside traps.
- Continuous monitoring: Implement regular monitoring of
mercury vapor levels in the operatory and staff exposure levels to ensure
compliance with occupational safety guidelines.
- Staff training: Provide regular training on the handling of
dental amalgam and mercury hygiene to all dental personnel.
- Patient communication: Inform patients about the use of
dental amalgam and the safety measures in place to minimize their exposure to
mercury.
- Alternative restorative materials: Consider using alternative
restorative materials, such as composite resins or glass ionomers, where
appropriate.
ANTIBIOTICS
Pharmacology
ANTIBIOTICS
Chemotherapy: Drugs which inhibit or kill the infecting organism and have no/minimum effect on the recipient.
Antibiotic these are substances produced by microorganisms which suppress the growth of or kill other micro-organisms at very low concentrations.
Anti-microbial Agents: synthetic as well as naturally obtained drugs that attenuate micro-organism.
SYNTHETIC ORGANIC ANTIMICROBIAL DRUGS
Sulfonamides
Trimethoprim-sulfamethoxazole
Quinolones – Ciprofloxacin
ANTIBIOTICS THAT ACT ON THE BACTERIAL CELL WALL
Penicillins
Cephalosporins
Vancomycin
INHIBITORS OF BACTERIAL PROTEIN SYNTHESIS
Aminoglycosides - Gentamicin
Antitubercular Drugs: Isoniazid & Rifampin
Tetracyclines
Chloramphenicol
Macrolides – Erythromycin, Azithromycin
Clindamycin
Mupirocin
Linezolid
ANTIFUNGAL DRUGS
Polyene Antibiotics (Amphotericin B, Nystatin and Candicidin)
Imidazole and Triazole Antifungal Drugs
Flucytosine
Griseofulvin
ANTIPROTOZOAL DRUGS
Antimalarial Drugs – Quinine, Chloroquine, Primaquine
Other Antiprotozoal Drugs – Metronidazole, Diloxanide, Iodoquinol
ANTIHELMINTHIC DRUGS
Praziquantel
Mebendazole
Ivermectin
ANTIVIRAL DRUGS
Acyclovir
Ribavirin
Dideoxynucleosides
Protease inhibitors
Significant Immune Findings in Periodontal Diseases
PeriodontologySignificant Immune Findings in Periodontal Diseases
Periodontal diseases are associated with various immune responses that can
influence disease progression and severity. Understanding these immune findings
is crucial for diagnosing and managing different forms of periodontal disease.
Immune Findings in Specific Periodontal Diseases
Acute Necrotizing Ulcerative Gingivitis (ANUG):
Findings:
PMN (Polymorphonuclear neutrophil) chemotactic defect: This
defect impairs the ability of neutrophils to migrate to the site of
infection, compromising the immune response.
Elevated antibody titres to Prevotella intermedia and
intermediate-sized spirochetes: Indicates an immune response to
specific pathogens associated with the disease.
Pregnancy Gingivitis:
Findings:
No significant immune findings reported: While pregnancy
gingivitis is common, it does not show distinct immune abnormalities
compared to other forms of periodontal disease.
Adult Periodontitis:
Findings:
Elevated antibody titres to Porphyromonas gingivalis and
other periodontopathogens: Suggests a heightened immune response to
these specific bacteria.
Occurrence of immune complexes in tissues: Indicates an immune
reaction that may contribute to tissue damage.
Immediate hypersensitivity to gingival bacteria: Reflects an
exaggerated immune response to bacterial antigens.
Cell-mediated immunity to gingival bacteria: Suggests
involvement of T-cells in the immune response against periodontal
pathogens.
Juvenile Periodontitis:
Localized Juvenile Periodontitis (LJP):
Findings:
PMN chemotactic defect and depressed phagocytosis: Impairs
the ability of neutrophils to respond effectively to bacterial
invasion.
Elevated antibody titres to Actinobacillus
actinomycetemcomitans: Indicates an immune response to this
specific pathogen.
Generalized Juvenile Periodontitis (GJP):
Findings:
PMN chemotactic defect and depressed phagocytosis: Similar
to LJP, indicating a compromised immune response.
Elevated antibody titres to Porphyromonas gingivalis:
Suggests an immune response to this pathogen.
Prepubertal Periodontitis:
Findings:
PMN chemotactic defect and depressed phagocytosis: Indicates
impaired neutrophil function.
Elevated antibody titres to Actinobacillus
actinomycetemcomitans: Suggests an immune response to this
pathogen.
Rapid Periodontitis:
Findings:
Suppressed or enhanced PMN or monocyte chemotaxis: Indicates
variability in immune response among individuals.
Elevated antibody titres to several gram-negative bacteria:
Reflects an immune response to multiple pathogens.
Refractory Periodontitis:
Findings:
Reduced PMN chemotaxis: Indicates impaired neutrophil migration,
which may contribute to disease persistence despite treatment.
Desquamative Gingivitis:
Findings:
Diagnostic or characteristic immunopathology in two-thirds of
cases: Suggests an underlying immune mechanism.
Autoimmune etiology in cases resulting from pemphigus and
pemphigoid: Indicates that some cases may be due to autoimmune
processes affecting the gingival tissue.
Regulation of glomerular filtration
Physiology
Regulation of glomerular filtration :
1. Extrinsic regulation :
- Neural regulation : sympathetic and parasympathetic nervous system which causes vasoconstriction or vasodilation respectively .
- Humoral regulation : Vasoactive substances may affect the GFR , vasoconstrictive substances like endothelin ,Angiotensin II , Norepinephrine , prostaglandine F2 may constrict the afferent arteriole and thus decrease GFR , while the vasodilative agents like dopamine , NO , ANP , Prostaglandines E2 may dilate the afferent arteriole and thus increase the filtration rate .
2. Intrinsic regulation :
- Myogenic theory ( as in the intrinsic regulation of cardiac output) .
- Tubuloglomerular feedback: occurs by cells of the juxtaglomerular apparatus that is composed of specific cells of the distal tubules when it passes between afferent and efferent arterioles ( macula densa cells ) , these cells sense changes in flow inside the tubules and inform specific cells in the afferent arteriole (granular cells ) , the later secrete vasoactive substances that affect the diameter of the afferent arteriole.
Keratoses (Horny Growth)
General Pathology
Keratoses (Horny Growth)
1. Seborrheic keratosis is a common benign epidermal tumor composed of basaloid (basal cell-like) cells with increased pigmentation that produce a raised, pigmented, "stuck-on" appearance on the skin of middle-aged individuals.
- they can easily be scraped from the skin's surface.
- frequently enlarge of multiply following hormonal therapy.
- sudden appearance of large numbers of Seborrheic keratosis is a possible indication of a malignancy of the gastrointestinal tract (Leser-Trelat sign).
2. An actinic keratosis is a pre-malignant skin lesion induced by ultraviolet light damage.
- sun exposed areas.
- parakeratosis and atypia (dysplasia) of the keratinocytes.
- solar damage to underlying elastic and collagen tissue (solar elastosis).
- may progress to squamous carcinoma in situ (Bowen's disease) or invasive cancer.
3. A keratoacanthoma is characterized by the rapid growth of a crateriform lesion in 3 to 6
weeks usually on the face or upper extremity.
- it eventually regresses and involutes with scarring.
- commonly confused with a well-differentiated squamous cell carcinoma.
Acid Etching on Enamel
Conservative DentistryEffects of Acid Etching on Enamel
Acid etching is a critical step in various dental procedures, particularly in
the bonding of restorative materials to tooth structure. This process modifies
the enamel surface to enhance adhesion and improve the effectiveness of dental
materials. Below are the key effects of acid etching on enamel:
1. Removal of Pellicle
Pellicle Removal: Acid etching effectively removes the
acquired pellicle, a thin film of proteins and glycoproteins that forms on
the enamel surface after tooth cleaning.
Exposure of Inorganic Crystalline Component: By
removing the pellicle, the underlying inorganic crystalline structure of the
enamel is exposed, allowing for better interaction with bonding agents.
2. Creation of a Porous Layer
Porous Layer Formation: Acid etching creates a porous
layer on the enamel surface.
Depth of Pores: The depth of these pores typically
ranges from 5 to 10 micrometers (µm), depending on the concentration and
duration of the acid application.
Increased Surface Area: The formation of these pores
increases the surface area available for bonding, enhancing the mechanical
retention of restorative materials.
3. Increased Wettability
Wettability Improvement: Acid etching increases the
wettability of the enamel surface.
Significance: Improved wettability allows bonding
agents to spread more easily over the etched surface, facilitating better
adhesion and reducing the risk of voids or gaps.
4. Increased Surface Energy
Surface Energy Elevation: The etching process raises
the surface energy of the enamel.
Impact on Bonding: Higher surface energy enhances the
ability of bonding agents to adhere to the enamel, promoting a stronger bond
between the tooth structure and the restorative material.