Objective To compare the effect of guiding boneregeneration between l-ethyl-3(3-diaminopropyol)-carbodiimide(EDAC)crosslinked acellular bovine pericardium (ABP) and medical collagen membrane (CM). Methods Defects of 7 mm×7 mm×5 mm were created in both mandibles of 24 rabbits, which weighted 2.6～3.5 kg. One side defect was covered with EDAC-crosslinked ABP(EDAC-crosslinked ABP group), the other side defect with medical CM as control(CM group). The ability of bone defect repair and change ofboth membrane materials were evaluated by gross observation, histological study and computer graphic analysis in the 4th, 8th, 16th and 24th weeks after operation. Results The surface of bone defects was even, consistent with adjacent normal bonein EDACcrosslinked ABP group, while that of bone defects was of no evenness in CM group in the 16th and the 24th weeks. The histological observation showed that bone trabecula formed in the EDAC-crosslinked ABP group and fibrous connective tissue was seen in CM group in the 16th and the 24th weeks. There were no significant differences in new bone percentage of bone defects between 2 groups inthe 4th and the 8th weeks(P＞0.05). In the 16th week new bone percentage of bone defects was 81.99%±3.92% in EDAC-crosslinked ABP group and 76.35%±4.29% in CM group, showing significant difference (Plt;0.05). The average percentage of absorption in EDAC-crosslinked ABP group was 16.57%, 27.94%, 65.61% and85.72% in the 4th, 8th, 16th and 24th weeks respectively, while that in CM group was more than 50% in the 4th week and completely degraded at the end of 8 weeks. Conclusion EDAC-crosslinked ABP has a better effect on guiding bone regeneration than CM in the repair of bone defects.
Objective To evaluate the results of the reconstruction of the soft tissue defects following the en block resection of tongue cancer using free anterolateral thigh myocutaneous flaps. Methods From November 2006 to December 2008, 109 cases underwent the reconstruction of the soft tissue defects following the en block resection of tongue cancer using free anterolateral thigh myocutaneous flaps. There were 75 males and 34 females with an age of 23-75 years (50.4 yearson average). The disease course was 1-6 months. According to 2002 International Union Control Cancer (IUCC) criterionfor TNM stage, there were 35 cases of T2N0M0, 8 cases of T2N1M0, 2 cases of T2N2M0, 31 cases of T3N0M0, 12 cases of T3N1M0, 7 cases of T3N2M0, 5 cases of T4N0M0, 4 cases of T4N1M0, 3 cases of T4N2M0, and 2 cases of T4N3M0. The range of tongue defect was 5 cm × 3 cm to 12 cm × 8 cm. The flap area ranged from 7 cm × 4 cm to 20 cm × 8 cm. Eighty-two patients with T3, T4 and positive lymph node metastasis determined by pathological examination after operation received radiotherapy. The vital ity of the flaps and the heal ing of the wounds were observed postoperatively. The shape and function of the reconstructed tongue were determined, the influences on function at donor site were evaluated and the flap tolerance to radiotherapy was investigated during the follow-up period. Results Mouth floor mandibular fistula occurred in 5 cases 5-7 days after operation, seroma formation in 1 case and wound dehiscence in another case at the donor site; the wounds healed by secondary intention after dressing. The other wounds healed primarily. All 105 flaps survived completely, 3 flaps developed partial necrosis 3-5 days after operation, the wounds healed after dressing; and 1 flap failed 3 days after operation, then it was removed and defects was repaired using pectoral is major muscle flap. Bl isters occurred in 8 flaps (all being thinning flaps) 1 day after operation. The overall complete survival of the flap was 96.3% (105/109). The patients were followed up for 0.5-2.5 years (1.2 years onaverage). Although the flaps had a l ittle atrophy, the shape of the reconstructed tongue was still satisfactory with suitable tonguemandibular groove. No depression was observed in the mandibular region. The speech as well as swallowing function were well recovered. The scar was easily hidden with no important functional impairment at the donor site. No flap necrosis occurred in all the patients who received postoperative radiotherapy. Conclusion Free anterolateral thigh myocutaneous flap transplantation is safe and rel iable, and it has the advantages of the better result at the recipient site, the less morbidity at the donor site, fewer postoperative compl ications and excellent tolerance to radiotherapy. So it is an ideal flap to repair soft tissue defects following the en block resection of tongue cancer.