Surgical methods involving cutting and sealing tissue include affixing a first adjunct material to tissue at a treatment site, such as by stapling the adjunct to tissue. A second adjunct material is applied to at least a portion of the first adjunct material such that the second adjunct material interacts with the first adjunct material to form a seal in an area of the tissue covered by at least one of the first and the second adjunct material. The resulting tissue sealing structure, which includes a combination of the two adjuncts, is believed to be superior to the sealing properties of either adjunct alone.