NEET MDS Lessons
General Medicine
Systemic Antibiotics
- Most photosensitizing: Doxycycline
- Only one causing tooth discoloration: Minocycline
Local Drug Delivery
- Atridox: Doxycycline
- Arestin: Minocycline
- Elyzol: Metronidazole
- Periochip: Chlorhexidine
- Actisite: Tetracycline
Host Modulation
- SDD (Sub – antimicrobial Dose Doxycycline): Only FDA – approved host modulating agent
- Normal count + ↑ BT: Platelet functional defect
- Small platelets: Wiskott – Aldrich syndrome
- ITP: Antibody against platelets, ↑ bleeding time
- Platelet transfusion not indicated in immunologic thrombocytopenia
- Thrombocytopenia not seen in Henoch – Schönlein purpura
- MAP formula: Diastolic + 1/3 Pulse Pressure
- Pulse Pressure: Systolic – Diastolic
- Sphygmomanometer readings: Slightly higher than intra-arterial
- J Curve Phenomenon: Excessive BP lowering → adverse cardiac events
- Best drug for angina with HTN: Metoprolol
- Contraindicated in diabetic HTN: Thiazides
- ACEI side effect: Hyperkalemia
- Aliskiren: Direct renin antagonist
Classification of Periodontal Pockets
Periodontal pockets are an important aspect of periodontal disease, reflecting the health of the supporting structures of the teeth. Understanding the classification of these pockets is essential for diagnosis, treatment planning, and management of periodontal conditions.
Classification of Pockets
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Gingival Pocket:
- Also Known As: Pseudo-pocket.
- Formation:
- Formed by gingival enlargement without destruction of the underlying periodontal tissues.
- The sulcus is deepened due to the increased bulk of the gingiva.
- Characteristics:
- There is no destruction of the supporting periodontal tissues.
- Typically associated with conditions such as gingival hyperplasia or inflammation.
-
Periodontal Pocket:
- Definition: A pocket that results in the destruction of the supporting periodontal tissues, leading to the loosening and potential exfoliation of teeth.
- Classification Based on Location:
- Suprabony Pocket:
- The base of the pocket is coronal to the alveolar bone.
- The pattern of bone destruction is horizontal.
- The transseptal fibers are arranged horizontally in the space between the base of the pocket and the alveolar bone.
- Infrabony Pocket:
- The base of the pocket is apical to the alveolar bone, meaning the pocket wall lies between the bone and the tooth.
- The pattern of bone destruction is vertical.
- The transseptal fibers are oblique rather than horizontal.
- Suprabony Pocket:
Classification of Periodontal Pockets
-
Suprabony Pocket (Supracrestal or Supraalveolar):
- Location: Base of the pocket is coronal to the alveolar bone.
- Bone Destruction: Horizontal pattern of bone loss.
- Transseptal Fibers: Arranged horizontally.
-
Infrabony Pocket (Intrabony, Subcrestal, or Intraalveolar):
- Location: Base of the pocket is apical to the alveolar bone.
- Bone Destruction: Vertical pattern of bone loss.
- Transseptal Fibers: Arranged obliquely.
Classification of Pockets According to Involved Tooth Surfaces
-
Simple Pocket:
- Definition: Involves only one tooth surface.
- Example: A pocket that is present only on the buccal surface of a tooth.
-
Compound Pocket:
- Definition: A pocket present on two or more surfaces of a tooth.
- Example: A pocket that involves both the buccal and lingual surfaces.
-
Spiral Pocket:
- Definition: Originates on one tooth surface and twists around the tooth to involve one or more additional surfaces.
- Example: A pocket that starts on the mesial surface and wraps around to the distal surface.
- Scaling in 2 appointments within 24 hours
- Tongue brushing with 1% chlorhexidine gel
- 0.2% chlorhexidine rinse
- 1% chlorhexidine pocket irrigation
Oral Hygiene Tools
Toothbrush Bristle Diameter:
- Soft: 0.007" (0.2 mm)
- Medium: 0.012" (0.3 mm)
- Hard: 0.014" (0.4 mm)
Brushing Techniques:
- Roll: Modified Stillman
- Circular: Fones
- Vertical: Leonard
- Horizontal: Scrub
Scaling Instruments
- Gracey curettes: Only outer cutting edge
- Universal curettes: Both edges cutting
- Langer curettes: Gracey shank + Universal blade
- Best grasp: Modified pen grasp (tripod effect)
- Scaling angle: 45 – 90°
Ultrasonic Scaling
- Vibration frequency: 18,000 – 50,000 cycles/sec
Stroke Types
- Exploratory: Light feeling (with probes)
- Scaling: Short powerful pull
- Root planing: Moderate to light pull
Calculus Composition
- Brushite: More common in mandibular anterior
- Magnesium whitlockite: More common in posterior
- Ca:P ratio: Higher subgingivally
- Mineralization: 50% in 2 days, 60 – 90% in 12 days
Microbiology
- First colonizers: S. salivarius and S. mitis
- Red complex: P. gingivalis, T. denticola, T. forsythia (cause BOP)
- Growth enhancement: P. gingivalis grows better with succinate (C. ochracea) and protoheme (C. rectus)
Pellicle Structure
- Basal layer: Thin, difficult to remove
- Globular layer: 1 μm thick, easier to detach
Bacterial Recognition
- Gram positive: Activate TLR2 → IL – 8
- Gram negative: Activate TLR4 → TNF – α
Junctional Epithelium
The junctional epithelium (JE) is a critical component of the periodontal tissue, playing a vital role in the attachment of the gingiva to the tooth surface. Understanding its structure, function, and development is essential for comprehending periodontal health and disease.
Structure of the Junctional Epithelium
-
Composition:
- The junctional epithelium consists of a collar-like band of stratified squamous non-keratinized epithelium.
- This type of epithelium is designed to provide a barrier while allowing for some flexibility and permeability.
-
Layer Thickness:
- In early life, the junctional epithelium is approximately 3-4 layers thick.
- As a person ages, the number of epithelial layers can increase significantly, reaching 10 to 20 layers in older individuals.
- This increase in thickness may be a response to various factors, including mechanical stress and inflammation.
-
Length:
- The length of the junctional epithelium typically ranges from 0.25 mm to 1.35 mm.
- This length can vary based on individual anatomy and periodontal health.
Development of the Junctional Epithelium
- The junctional epithelium is formed by the confluence of the oral epithelium and the reduced enamel epithelium during the process of tooth eruption.
- This fusion is crucial for establishing the attachment of the gingiva to the tooth surface, creating a seal that helps protect the underlying periodontal tissues from microbial invasion.
Function of the Junctional Epithelium
- Barrier Function: The junctional epithelium serves as a barrier between the oral cavity and the underlying periodontal tissues, helping to prevent the entry of pathogens.
- Attachment: It provides a strong attachment to the tooth surface, which is essential for maintaining periodontal health.
- Regenerative Capacity: The junctional epithelium has a high turnover rate, allowing it to regenerate quickly in response to injury or inflammation.
Clinical Relevance
- Periodontal Disease: Changes in the structure and function of the junctional epithelium can be indicative of periodontal disease. For example, inflammation can lead to increased permeability and loss of attachment.
- Healing and Repair: Understanding the properties of the junctional epithelium is important for developing effective treatments for periodontal disease and for managing healing after periodontal surgery.