Periodontology

Classification by Extent

• Generalized: >30% sites affected

Classification by Severity

• Moderate: 3 – 4 mm bone loss
• Severe: >5 mm bone loss

Aggressive Periodontitis

• Rate: 3 – 4 times faster bone loss than chronic
• Classic sign: Arc – shaped bone loss (distal 2nd premolar to mesial 2nd molar)
• Associated: HLA A9 and B15 antigens
• Receptor defect: Poorly functional monocyte FcγR2

Pain Characteristics

• Periodontal pocket pain: "Deep in bone" feeling

Bone Loss Patterns

• Radius of action: 1.5 – 2.5 mm (Page & Schroeder)
• Reverse architecture: Facial/lingual plates lost, radicular bone preserved
• TFO signs: Increased mobility (first clinical sign)