ABSTRACT
Driven by enormous clinical need, interest in peripheral nerve regeneration has become a prime focus of research and area of growth within the field of tissue engineering. While using autologous donor nerves for bridging peripheral defects remains today's gold standard, it remains associated with high donor site morbidity and lack of full recovery. This dictates research towards the development of biomimetic constructs as alternatives. Based on current concepts, this review summarizes various approaches including different extracellular matrices, scaffolds, and growth factors that have been shown to promote migration and proliferation of Schwann cells. Since neither of these concepts in isolation is enough, although each is gaining increased interest to promote nerve regeneration, various combinations will need to be identified to strike a harmonious balance. Additional factors that must be incorporated into tissue engineered nerve constructs are also unknown and warrant further research efforts. It seems that future directions may allow us to determine the "missing link".
Subject(s)
Biomimetic Materials , Peripheral Nerves/physiology , Schwann Cells/cytology , Schwann Cells/physiology , Tissue Engineering , Animals , Cell Proliferation , Cells, Cultured , Extracellular Matrix/metabolism , Forecasting , Humans , Models, Neurological , Nerve Growth Factors/pharmacology , Nerve Regeneration/drug effects , Nerve Regeneration/physiology , Peripheral Nerve Injuries , Peripheral Nerves/drug effectsABSTRACT
Fifty cases of oromandibular reconstruction using vascularized free flaps to evaluate functional parameters of results were evaluated. There were 23 iliac crest flaps, 17 fibula flaps, 30 ulnar forearm flaps, and 3 radial forearm flaps with bone. Thirteen female and 37 male patients comprised the study, with a mean age of 57.66 years. Squamous-cell carcinoma (SCC) constituted 86% of cases, of which 60% were T4 lesions and 13.9% were recurrent. Anterolateral mandibular defects constituted 48.7%, and the mean bone gap was 8.13 cm. Functional evaluation was based on the University of Washington Questionnaire (UWQ) through phone calls and personal communication. The mean hospital stay was 12.42 days. The external carotid (75%) and facial (18.3%) were the main recipient arteries. The internal jugular (47.05%) was the main recipient vein. Overall flap survival was 95.9%. Three flaps were lost due to unsalvageable venous thrombosis. Major local complications such as partial flap loss, hematoma, and orocervical fistula constituted 10% of cases. Speech was classified as "excellent" and "good" in 43.3% of cases. Swallowing was identified as "excellent" and "good" in 53.3% of cases. Cosmetic acceptance was rated "good" in 63.3% of cases. Vascularized free flap reconstruction of oromandibular defects provides excellent functional and aesthetic results. The majority of patients are able to tolerate a regular diet. Intelligible speech and acceptable appearance are restored, providing patient satisfaction.
Subject(s)
Bone Transplantation/methods , Carcinoma, Squamous Cell/surgery , Mandibular Neoplasms/surgery , Plastic Surgery Procedures/methods , Surgical Flaps/blood supply , Adult , Aged , Carcinoma, Squamous Cell/pathology , Esthetics , Female , Follow-Up Studies , Graft Survival , Humans , Male , Mandibular Neoplasms/pathology , Middle Aged , Patient Satisfaction , Retrospective Studies , Risk Assessment , Treatment OutcomeABSTRACT
The ulnar forearm flap is not frequently utilized for oromandibular reconstruction. This study evaluated the usefulness of the ulnar free flap for reconstruction. A retrospective study of 32 patients was conducted. The ulnar forearm flap was combined with an osseous flap in 24 patients. Nine females and 23 males with a mean age of 58.15 years comprised our study population. Squamous-cell carcinoma was the diagnosis in 93.75% of cases (56.25% T4), of which 20% were recurrent. Functional evaluation of swallowing was based on the University of Washington Questionnaire (UWQ). The mean hospital stay was 9.8 days. The external carotid (100%) was the recipient artery, and the internal jugular (74.07%) was the main recipient vein. Overall flap survival was 96.8%. One flap was lost due to unsalvageable venous thrombosis. Major local complications were seen in 9.4% of cases and included partial flap loss, hematoma, and an orocutaneous fistula. At the time of this study, 21 patients were available for functional evaluation. Speech was rated excellent and good in 33.3% of patients. Swallowing was found good in 28.6% of patients. Chewing was rated excellent and good in 47.6% of patients. Cosmetic acceptance was rated good in 71.4% of cases. The ulnar forearm is a useful free flap in oromandibular reconstruction. It is available when the radial artery is the dominant artery of the hand. Being more hidden, it may be more cosmetically accepted. It affords pliable soft tissue for lining and/or covering of oromandibular defects, and can be used as a second choice after other free-flap failures.
