The Simplified Oral Hygiene Index (OHI-S) is a tool used to assess oral hygiene status by evaluating specific tooth surfaces. The teeth mentioned in option 1 include the lingual surfaces of the lower first molars (36, 46) and the facial surfaces of the upper incisors and canines (11, 16, 26, 31). These surfaces are typically assessed because they are representative of overall oral hygiene and are commonly affected by plaque accumulation.

Antibodies neutralize exotoxins by binding to their protein components, preventing them from interacting with host cells and causing damage. This immune response is critical for protecting the host from the harmful effects of these toxins.

When heated to 56°C - 62°C, Gutta Percha gets converted to the A form, which is crucial for its expansion during the sealing process.

Chronic venous insufficiency is characterized by a range of symptoms and physical findings, including varicose veins, pitting edema, and venous ulcers, particularly around the medial malleolus (ankle). These symptoms result from impaired venous return and increased venous pressure in the lower extremities.

Hilton's method is a surgical technique primarily used for the drainage of abscesses. This method involves creating an incision to allow the pus to escape, thereby relieving pressure and promoting healing.