The evaluation of flap growth and long-term results of pediatric mandible reconstructions using free fibular flaps.

Currently, the free fibular flap is well accepted as the first choice for mandibular reconstruction. Achieving functional results in pediatric patients requires a different approach than that employed for mature patients. Because the pediatric craniofacial skeleton continues to grow, reconstruction is more challenging, and the long-term results can be different from those of adult patients. In this study, we sought to measure flap growth objectively in our series. Ten pediatric patients who underwent reconstruction with free fibular flaps were retrospectively reviewed. Flap growth was evaluated by comparing the intraoperative photographs with photographs of the control panoramic mandibular radiographs taken using photo-anthropometric techniques. The measurements were converted to proportionality indices (PI), and these indices were compared. Subsequent complications and functional results were also evaluated. The mean patient age was 11.8 years, and the mean follow up was 57.7 months. The mean preoperative PI value was 10.74 ± 2.47. The mean postoperative PI value was 12.52 ± 2.34. The mean difference between the preoperative and postoperative PI values was -1.78 ± 0.53. These photo-anthropometric data clearly illustrated the growth of the fibular flaps (P = 0.001). None of these patients exhibited nonunion of the fractures; however, one patient experienced a delayed union, one had chronic temporomandibular joint pain, and one had chronic temporomandibular joint luxation. In two patients, the inter-incisive measurements were below the third percentile, and two additional patients had grade 2 eating abilities, which can be regarded as poor. All of the patients had symmetric mandibular contours. Free fibular flaps continue to grow in pediatric patients. This flap is a "workhorse" flap in children because it adapts to the craniofacial skeleton via its ability to grow, and this ability results in subsequent good cosmetic and functional results.

Comparison of skin effects of immediate treatment modalities in experimentally induced hydrofluoric acid skin burns.

Hydrofluoric acid (HF) burns cause immediate damage and painful long-term sequellae. Traditionally, chelating agents have been used as the initial treatment for such burns. We have introduced epidermal growth factor (EGF) into an HF model to compare EGF with Ca(2+) and Mg(2+) treatments; 40 Sprague Dawley rats were divided into five groups. Each rat suffered a 6 × 4 cm(2) burn induced by 40% HF. Group 1 had no treatment, group 2 had saline injected beneath the burn, group 3 received magnesium sulphate injections, group 4 received calcium gluconate and group 5 received EGF. Specimens were evaluated via planimetry and biopsy at intervals of 4, 8, 24 and 72 hours. Fluid losses were significantly less in the Mg(2+) and EGF groups. The EGF group had the smallest burn area, least oedema, least polymorphonuclear granulocyte (PMN) infiltration, most angiogenesis and highest fibroblast proliferation of any group (P < 0·005). EGF limited HF damage morphologically and histologically more effectively than Ca(2+) or Mg(2+). This finding indicates that HF treatment via growth factors may be an improvement over chelation therapy.

The effect of melatonin on a dorsal skin flap model.

BACKGROUND: Melatonin (Mel) has a very potent antioxidant activity, depending mainly on its capacity to act as an electron donor. Recently, the antioxidant property of Mel has been much emphasized. In this study, the dorsal skin flap model was used to investigate the effect of Mel in flap viability in rats. MATERIAL AND METHODS: Totally 28 Wistar Albino rats were divided into four groups: control group (C) (n = 7), local treatment group (L) (n = 7), systemic low-dose melatonin treatment group (LT) (n = 7), and systemic high-dose melatonin treatment group (HT) (n = 7). The necrosis rate of the skin flaps was observed seven days after the operation by a blinded observer. Oxidative stress was assessed by determining malondialdehyde (MDA) level, and effects of melatonin on antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were measured. Vascularity, epithelial thickness, and fibroblast proliferation of dorsal skin flaps were assessed histologically. RESULTS: Amount of MDA were found significantly lower (p < .05), and the flap viability, CAT, SOD, vascularity, fibroblast proliferation, and epithelial thickness were found significantly higher (p < .05) in groups HT than in groups C, L, and LT statistically. CONCLUSION: Our results showed that the usage on different doses of melatonin could play an important role in the process of flap viability and further studies will focus on these areas of interest.

Effects of taurine on reperfusion injury.

Taurine is an organic acid, which has a very important function in the human body. Recently, the antioxidant property of taurine has been much emphasised. In this study, the gracilis muscle flap model was used to investigate the effect of taurine in ischaemia/reperfusion injury in rats. Totally 32 Sprague-Dawley rats were divided into two groups: control group (n = 16) and the treatment group with taurine (n = 16). After elevation of the gracilis muscle flap, 4 h of ischaemia was performed in both groups. Thirty min before the reperfusion, taurine (200 mg kg(-1)) was injected intravenously. After 24 h of reperfusion, the amount of malondialdehyde (MDA), tissue water content and flap viability were evaluated. After 72 h of reperfusion, histological findings were evaluated. Amount of MDA and tissue water content were significantly lower (p < 0.005), and the flap viability was significantly higher (p < 0.005) in the treatment group 24 h after reperfusion. On comparing the outcomes of histological analysis between control and treatment groups, the amounts of collagen, fibroblast and angiogenesis in treatment group were significantly higher than those in the control group. However, the amount of polymorphonuclear leucocyte and tissue necrosis in the treatment group were significantly lower than in the control group. Our results showed that taurine played an important role in the process of ischaemia/reperfusion injury and presented certain protective effects with the improvement in flap survival after ischaemia/reperfusion injury.

Osteogenic capacities of tibial and cranial periosteum: a biochemical and histologic study.

The periosteum has an important role in bone regeneration. The purpose of this study was to evaluate and compare the osteogenic capacities of tibial and cranial periosteum. To achieve this, 44 New Zealand male rabbits were divided into two groups, each consisting of 22 rabbits. In group 1, periosteal flaps were prepared on the tibia of the posterior cruris of each side. In group 2, bilateral periosteal flaps were prepared on the cranial region. New bone formation was estimated quantitatively by measuring the alkaline phosphatase and osteocalcin levels, because they are the indicators of osteoblastic activity. At weeks 1, 2, 4, and 8, biopsies were taken from five animals of each group for biochemical analyses, and at weeks 2 and 8, biopsies were taken for histologic evaluation. Higher alkaline phosphatase and osteocalcin levels were evaluated in group 1, and more bone formation was observed in group 1. The results showed that osteogenic capacity is higher in tibial periosteum than cranial periosteum.

Van der Woude syndrome in twins.

This article discusses monozygotic twin patients with Van der Woude syndrome, the most common form of syndromic cleft lip and palate, who have concordant manifestations. The syndrome has an autosomal dominant hereditary pattern with variable expressivity and a high degree of penetrance with clinical features, including lower lip sinuses with a cleft lip, cleft palate, or both. Some mutations have been found to cause this disorder. Genetic counseling and informing patients about inheritance is crucial. The appearance, etiology, genetic aspects, differential diagnosis, and treatment modalities are discussed. To the authors' knowledge, this is the third report of monozygotic concordant twins with this syndrome in the literature.

Alopecia treatment with scalp expansion: some surgical fine points and a simple modification to improve the results.

In the current study, authors present their clinical experience with the esthetic reconstruction of alopecia by means of a tissue expansion technique in 74 consecutive patients who were treated between May 1986 and June 2002 in the Department of Plastic and Reconstructive Surgery. The principles of the conventional technique are mentioned briefly, but the authors essentially tried to explain a number of surgical fine points together with some simple modifications so as to get the maximum profit from the expanded tissue and to decrease the complication rate. In the first 39 patients of this study, who were treated with a conventional tissue expansion technique, the major complication rate was found to be 15.4%. In the last 35 patients, this rate was found to be decreased to 5.7%. The improvement in the major complication rate is attributed to the authors' surgical modifications compared with the conventional technique. The article provides a supplement to the existing literature, underscoring the importance of some surgical fine points and outlining a systematic way of planning expander placement and tissue expansion.

Comparing the osteogenic capacities of bone substitutes: hydroxyapatite, high-density porous polyethylene, and bone collagen: a biochemical and histological analysis.

Several inorganic materials have been shown previously to hold some osteogenic capacity. The purpose of this study is to compare the bone-forming abilities of hydroxyapatite ceramic, high-density porous polyethylene, and bone collagen within the periosteal island flap of rabbit tibia using histological and biochemical analysis. With this goal, four discrete experimental groups were formed, each comprising 22 New Zealand male rabbits. A sac was created on each rabbit tibial periosteum flap in each of the groups, and each of the previously mentioned materials was placed within this sac separately. One of these groups was thought as a control group without any material being placed inside the periosteal sac. Biopsies were taken at weeks 1, 2, 4, and 8 for biochemical analysis and at weeks 2 and 8 for histological evaluation. Neo-osteogenesis was evaluated quantitatively by determination of alkaline phosphatase and osteocalcin levels biochemically as well as by the percentage of new bone formation inside the periosteal sac histologically. Results show statistically that the osteogenic effect of high-density porous polyethylene is greater than that of the other materials used in this study (P < 0.05).

Cancellous bone grafting in alveolar cleft repair: new experience.

Bone grafting plays an important role in the dental rehabilitation of patients with alveolar cleft. During the period between 1993 and 2001, 12 patients with alveolar clefts have been treated in our clinic. Cancellous iliac bone grafts were used in all 12 patients. Seven patients had left and five patients had right complete unilateral cleft lip and complete cleft palate operations. All patients had palatal fistulas. The ages were between 4 and 18 years (mean age, 10.5 y). Seven of them were female (58.4%) and 5 were male (41.6%). All the cancellous grafts survived. Enough filling and the closure of the fistulas were achieved except one patient who had wound dehiscence and partial graft loss. The patients experienced a limp for 2 days (mean time) because of the donor site. This surgical procedure achieves successful results if it is used with the proper indication in suitable cases.

Craniomaxillofacial fibrous dysplasia.

Fibrous dysplasia is a nonneoplastic developmental disease of osseous tissue. It is a lesion of unknown etiology, uncertain pathogenesis, and diverse histopathology. In this series of 16 patients with fibrous dysplasia of the craniomaxillofacial bones, the disease was generally monostotic and most commonly maxillary in location. Two patients demonstrated typical symptoms of the McCune Albright syndrome. Marked deformity or functional disturbances were the major indications for treatment. Total excision of the involved bone was the most successful form of treatment but produced the greatest functional and cosmetic deficits and long-term postoperative complications. A conservative therapeutic approach with a modest reduction in the bulk of these lesions may be sufficient to relieve signs and symptoms effectively. Periodic follow-up is indicated to detect recurrences or malignant changes in the early stages.

Different venous end-to-side microanastomotic techniques: comparative study in a new rat model.

End-to-side venous anastomosis is sometimes necessary when there is the lack of a suitable vein, when there is a size discrepancy in the veins to be repaired, or when the anastomosis of multiple veins is required. The effects of elliptical vs. slit venotomy on vessel patency have not been investigated in a flap model. A new, simple, reliable, and reproducible model is described in which the femoral vein of the groin flap is anastomosed to the side of the deep dorsal penile vein. Elliptical hole and slit venotomies were tested in 26 Sprague-Dawley rats, and the anastomoses were 100% patent. The type of venotomy was not found to affect patency. Either technique is equally valid in end-to-side venous anastomosis, and the model itself is convenient for training.