Which of the following is a common treatment for large cysts in the oral cavity?

Marsupialisation is a common treatment for large cysts in the oral cavity. This technique involves creating a surgical opening in the cyst and suturing the edges of the cyst wall to the oral mucosa. The result is the formation of a continuous drainage tract, which allows the cyst to drain and reduces its size over time. Marsupialisation is particularly useful for larger cysts because it preserves surrounding tissues and structures, promoting healing while avoiding more invasive procedures.

This method is often preferred when complete removal of the cyst is deemed too risky or if the cyst is too large for straightforward excision. By promoting drainage and reducing the cyst's volume, marsupialisation can sometimes lead to eventual resolution of the cyst.

Other treatments like extraction, root canal therapy, and immediate surgical removal might be less appropriate for large cysts due to various reasons such as the potential for compromising adjacent structures or complications associated with more extensive surgical procedures.