NEET MDS Lessons
Periodontology
Important Periodontal Indices
PMA Index
- Purpose: Assessment of gingival disease status
- Components: Papillary (P), Marginal (M), and Attached (A) gingiva scoring
Ramfjord Index
- Selected Teeth: 16, 21, 24, 36, 41, 44
- Rationale: Representative sampling of entire dentition
Merin's Classification
- Application: Patient recall scheduling based on periodontal status
- Categories: Maintenance intervals based on disease severity
Clinical Measurements
Gingival Sulcus Depth
- Primary Teeth: 1-2mm (shallower than permanent teeth)
- Permanent Teeth: 2-3mm in health
Level of Attachment
- Definition: Distance from cementoenamel junction (CEJ) to pocket base
- Clinical Significance: True measure of periodontal support loss
Fremitus Test
- Purpose: Diagnosis of tooth mobility
- Technique: Palpation during functional movements
| Virus | Key Info |
|---|---|
| Hepatitis E | Feco-oral spread; pregnancy = high mortality |
| Hepatitis B |
- Perinatal transmission (90%)
- Window phase: HBsAg ↓, anti-HBs ↑
- Infectivity: HBsAg + HBeAg
- First marker post-infection: HBsAg
- IgM anti-HBc = acute infection
- Reverse transcriptase → P gene
| Hepatitis C | Most chronic & linked to liver disease
| Hepatitis A | Prophylaxis: Human IgG
| Hepatitis E | Most epidemic-prone in India
| Councilman bodies | Seen in acute viral hepatitis
🧪 Glomerular Hematuria
| Urine Finding | Interpretation |
|---|---|
| >20% Dysmorphic RBCs | Suggests glomerular origin |
| RBC casts | Glomerular pathology |
| Creatinine clearance | Measures GFR |
💧 Nephrotic Syndrome
- Edema cause: Hypoalbuminemia
- Commonest cause (adults): Diabetes mellitus
- Lipid profile: ↓ HDL cholesterol
- Minimal change disease: No change on light microscopy
- Membranoproliferative GN: Tram-track appearance
- Membranous GN: Common in renal vein thrombosis
- Best test for renal vein thrombosis: CT angiography
Treatment Phases
- Phase 1: Non – surgical
- Phase 2: Surgical
- Phase 3: Restorative
- Phase 4: Maintenance Must progress through Phase 1 → 4 before Phase 2 or 3
Merin's Classification
- Class A: 6 months – 1 year recall
- Class B: 3 – 4 months recall
- Class C: 1 – 3 months recall
| Type | Key Feature |
|---|---|
| Beta Thalassemia | ↓ Beta chains, ↑ Alpha chains |
| Common mutation | Intron-1 |
| Diagnosis | Hb electrophoresis |
| Screening test | NESTROFT |
| Radiology sign | Hair-on-end skull appearance |
- Alpha Thalassemia: Caused by deletion of alpha genes
- HbH Disease: Deletion of 3 alpha chains
Gingival Crevicular Fluid (GCF)
Gingival crevicular fluid is an inflammatory exudate found in the gingival sulcus. It plays a significant role in periodontal health and disease.
A. Characteristics of GCF
- Glucose Concentration: The glucose concentration in GCF is 3-4 times greater than that in serum, indicating increased metabolic activity in inflamed tissues.
- Protein Content: The total protein content of GCF is much less than that of serum, reflecting its role as an inflammatory exudate.
- Inflammatory Nature: GCF is present in clinically normal sulci due to the constant low-grade inflammation of the gingiva.
B. Drugs Excreted Through GCF
- Tetracyclines and Metronidazole: These antibiotics are known to be excreted through GCF, making them effective for localized periodontal therapy.
C. Collection Methods for GCF
GCF can be collected using various techniques, including:
- Absorbing Paper Strips/Blotter/Periopaper: These strips absorb fluid from the sulcus and are commonly used for GCF collection.
- Twisted Threads: Placing twisted threads around and into the sulcus can help collect GCF.
- Micropipettes: These can be used for precise collection of GCF in research settings.
- Intra-Crevicular Washings: Flushing the sulcus with a saline solution can help collect GCF for analysis.
| Type | Features |
|---|---|
| Unconjugated | Absent in urine (bound to albumin); hemolysis |
| Conjugated | Seen in Dubin-Johnson |
| Diagnosis | BSP test (Dubin-Johnson) |
| Genetics | Crigler-Najjar Type II – Autosomal recessive |
| Cholestasis | ↑ 5’-nucleotidase |
| Hypothyroid | ↓ Alk Phos |