Which of the following is a type of absorbable suture used in ocular procedures?

Plain or chromic surgical gut is indeed a type of absorbable suture commonly used in ocular procedures. This material breaks down in the body over time, making it suitable for surgical applications where the suture does not need to remain indefinitely. The absorbable nature allows for natural tissue healing without requiring additional surgical intervention to remove the sutures.

Plain surgical gut is made from the submucosa of sheep or the serosa of cattle and is absorbed by the body through enzymatic degradation. Chromic gut is treated with chromic salt to slow down the absorption process, providing a longer retention time in tissue, which can be beneficial in certain surgical situations.

In contrast, the other options listed are non-absorbable sutures. Silk is a natural fiber that, although it provides excellent tensile strength and handling properties, does not absorb and remains in the body indefinitely. Polypropylene and polyester are synthetic materials that are also non-absorbable, offering durability and strength but requiring removal after healing. Therefore, plain or chromic surgical gut is the appropriate choice for absorbable sutures in ocular surgeries, ensuring effective healing without the need for subsequent removal.