Discussion Epithelialization Process of Free Fascial Flaps Used in Reconstruction of Oral Cavity Mucosa Defects in Dogs Discussion by Ziv M. Peled, M.D., and Julian J. Pribaz, M.D. Boston, Mass. In their article, Ug ˘urlu et al. describe their experience with free fascial flaps in the healing of intraoral lesions in a dog model. Specifically, they eloquently document the histologic changes associated with the healing of such flaps during the first 2 months after surgery. Their study is quite interesting and well exe- cuted, but we would like to address several additional points. The reconstruction of intraoral defects is complex and has progressively evolved over the past several years. Reconstruction with “like” tissue is always desirable, and replacement of intraoral defects with a highly specialized epi- thelial lining that can keep the oral cavity moist is the ideal. Among the first series of flaps designed to tackle these defects were the mus- culocutaneous flaps such as the pectoralis ma- jor myocutaneous flap. 1 As experience with these flaps grew, their limitations became more apparent. Among other problems, pectoralis major myocutaneous flaps resulted in conspic- uous donor-site defects (especially in female patients) and were often bulky because the harvested skin islands required a relatively large muscular cross section to supply enough perforators to the skin. In an effort to address these shortcomings, myocutaneous flaps were eventually replaced with the myofascial or sim- ple free muscle flaps. These flaps are less bulky, and a number of authors have documented that resurfacing of such intraoral flaps does not require a skin island or skin grafting, as the flaps become mucosal within the first month postoperatively. 2–4 The free dorsal thoracic fas- cia flap presented in this article represents the latest step in the evolution of the approach to intraoral defects. The authors describe a flap with many ap- pealing features. It is relatively easy to elevate, is large (8  10 cm), and it has a long vascular pedicle (average, 10 cm). The flap is thin and flexible, making it ideal for coverage of wounds with uneven or oddly shaped borders. Further- more, there is minimal donor-site morbidity. Finally, this fascial free flap can apparently be used to cover sizable defects (8  10 cm). Beyond all of these apparent advantages of the free dorsal thoracic fascia flap, and perhaps most striking, are the authors’ results. To begin, the authors report minimal con- traction of the wound (18 percent). These findings are quite an improvement over results using free muscle flaps, in which contraction rates vary from 33 to 50 percent. 4 We agree with the authors that the lack of a muscle component (with its inherent contractile abil- ity) in the free fascial flap may play a role in the paucity of contraction demonstrated in the present study. Just as impressive is the relatively well-organized appearance, both grossly and histologically, of the dermal component of the flap. The authors state that their fascial flap was “replaced by normally maturated fibrous tissue and the [muscle-only flaps are] replaced by atypically formed scar tissue.” Although we are uncertain as to the exact distinction the au- thors are trying to make, the notion of such a difference raises some interesting possibilities. What we are really talking about here are mes- enchymal-epithelial interactions between mu- cosal keratinocytes and dermal fibroblasts dur- ing wound healing. There are plenty of examples that such interactions do indeed oc- cur. For example, functioning of calvarial os- Received for publication October 3, 2003. DOI: 10.1097/01.PRS.0000105627.40313.5C 924