NEET MDS Lessons
General Medicine
PERIOTEST Device in Periodontal Assessment
The PERIOTEST device is a valuable tool used in dentistry to assess the mobility of teeth and the reaction of the periodontium to applied forces. This lecture covers the principles of the PERIOTEST device, its measurement scale, and its clinical significance in evaluating periodontal health.
Function: The PERIOTEST device measures the reaction of the periodontium to a defined percussion force applied to the tooth. This is done using a tapping instrument that delivers a controlled force to the tooth.
Contact Time: The contact time between the tapping head and the tooth varies between 0.3 and 2 milliseconds. This duration is typically shorter for stable teeth compared to mobile teeth, allowing for a quick assessment of tooth stability.
PERIOTEST Scale
The PERIOTEST scale ranges from -8 to +50, with specific ranges indicating different levels of tooth mobility:
| Readings | Inference |
|---|---|
| -8 to 9 | Clinically firm teeth |
| 10 to 19 | First distinguishable sign of movement |
| 20 to 29 | Crown deviates within 1 mm of its normal position |
| 30 to 50 | Mobility is readily observed |
Clinical Significance
Assessment of Tooth Mobility:
The PERIOTEST device provides a quantitative measure of tooth mobility,
which is essential for diagnosing periodontal disease and assessing the
stability of teeth.
Correlation with Other Measurements:
The PERIOTEST values correlate well with:
-
Tooth Mobility Assessed with a Metric System: This allows for a standardized approach to measuring mobility, enhancing the reliability of assessments.
-
Degree of Periodontal Disease and Alveolar Bone Loss: Higher mobility readings often indicate more severe periodontal disease and greater loss of supporting bone, making the PERIOTEST a useful tool in monitoring disease progression.
Treatment Planning:
Understanding the mobility of teeth can aid in treatment planning,
including decisions regarding periodontal therapy, splinting of mobile teeth, or
extraction in cases of severe mobility.
COPD
- Reid's index: Used in chronic bronchitis
- Emphysema features: ↓DLCO, weight loss, pneumothorax risk
- Chronic bronchitis: Polycythemia
- GOLD criteria: COPD severity assessment
- BODE index: Lung transplant evaluation
Sleep Apnea
Definition: Breathing pause ≥10 seconds during sleep
ASTHMA
Diagnosis & Pathophysiology
- Best diagnostic test: Demonstration of reversible obstruction
- Small airways involved
- Idiosyncratic asthma: Normal IgE levels
- Aspirin-sensitive asthma: Associated with nasal polyps
Key Points
- Charcot-Leyden crystals: Eosinophil granules
- Nebulizer droplet size: <2.5 μm
- Most severe attack indicator: Bradycardia
- Montelukast: NOT useful in acute bronchial asthma
🔬 Key Features & Forms
- Most infective form: Cavitary lesion
- Primary TB Presentation: Unilateral hilar lymphadenopathy
- Rich focus: Meninges (associated with TB meningitis)
- Cavitation: Absent in HIV-associated or primary TB
💡 Special Manifestations
- Hypersensitivity to Mycobacteria: Phlyctenular conjunctivitis
- Poncet’s disease: Joint pains without active arthritis
- Miliary TB: Mantoux test negative
- Recurrent hemoptysis source: Bronchial artery
💊 Drug Details
- Streptomycin: Not used in TB meningitis
- Bedaquiline: New drug for MDR-TB
- Mobility Tests: Perio test, Fremitus test.
- Bone Evaluation: Transgingival probing.
- Halitosis Detection: Gold standard = Organoleptic analysis.
- Indices:
- PMA Index: Gingival disease.
- Ramfjord Index Teeth: 16, 21, 24, 36, 41, 44.
- Merin’s Classification: Patient recall.
- Surrogate Endpoint: Reduction in probing depth.
Wilson's disease is an autosomal recessive disorder of copper metabolism caused by mutations in the ATP7B gene, resulting in impaired biliary copper excretion and toxic copper accumulation in tissues.
Pathophysiology
- Basic defect: Decreased biliary copper excretion due to defective ATP7B protein
- Mechanism: Impaired incorporation of copper into ceruloplasmin and reduced copper transport into bile
- Result: Copper accumulation in liver, brain, cornea, and other organs
Clinical Manifestations
Hepatic (Most common initial presentation)
- Acute hepatitis
- Chronic hepatitis
- Cirrhosis
- Fulminant hepatic failure
Neurological
- Movement disorders (tremor, dystonia, chorea)
- Psychiatric symptoms (depression, psychosis, behavioral changes)
- Dysarthria and dysphagia
- Cognitive impairment
Ophthalmologic
- Kayser-Fleischer rings (pathognomonic copper deposits in Descemet's membrane)
- Sunflower cataracts
Other Features
- Renal tubular acidosis
- Hemolytic anemia
- Arthritis
- Cardiomyopathy (rare)
Diagnostic Workup
- Serum ceruloplasmin: Usually decreased (<20 mg/dL)
- 24-hour urine copper: Elevated (>100 μg/24h)
- Hepatic copper content: Gold standard (>250 μg/g dry weight)
- Ophthalmologic examination: Slit-lamp for Kayser-Fleischer rings
- Genetic testing: ATP7B gene mutations
- Brain MRI: "Face of giant panda" sign in severe cases
Treatment
Chelation Therapy
- D-penicillamine: First-line, may worsen neurological symptoms initially
- Trientine: Alternative chelator, better tolerated neurologically
- Tetrathiomolybdate: For neurological presentations
Zinc Therapy
- Zinc acetate/sulfate: Blocks copper absorption, maintenance therapy
- Preferred for asymptomatic patients and maintenance
Smoking
- Pack years = Packs/day × Years of smoking
Diabetes
- Causes collagen cross – linking via AGEs formation
AIDS
- Most common oral lesion: Candidiasis
- Most common oral malignancy: Kaposi sarcoma
Critical Measurements
- PMN threshold: 60% in junctional epithelium → tissue detachment
- Clinical significance: Level 1 provides tangible benefit of large size
Important Ratios & Numbers
- GCF glucose: 3 – 4× serum levels
- Aggressive vs chronic periodontitis: 3 – 4× faster bone loss
- Mineralization timeline: 50% (2 days), 60 – 90% (12 days)