Secondary correction of the unilateral cleft lip nose using a conchal composite graft

The secondary deformity of the unilateral cleft lip nose has many components. One is the dorsal dislocation of the lateral crus of the alar cartilage. We used a conchal composite graft positioned between the piriform aperture and the lateral crus and the upper lateral cartilage to correct this dislocation in nine patients. We believe that this graft is effective because it elevates the lateral crus of the alar cartilage off the depressed piriform aperture. This technique is very simple to perform, and it is easy to achieve nasal symmetry. Our results have been quite satisfactory, with no recurrence of dorsal dislocation. The donor site was covered by a subcutaneous pedicled flap from the cephaloauricular sulcus, leaving an inconspicuous deformity.     

Augmentation of the atrophic mandible with a vascularized rib graft

A patient with a 29-year history of denture wearing had her mandible augmented with a vascularized rib graft. The rib was contoured to fit the arch of the mandible and vascularized by means of the facial arteries to the intercostal vessels. The nutrient artery was not included in the vascularized bone graft. Cortical cancellous bone chips were packed around the rib to augment the buccal surface of the rib graft. Periosteal perfusion and vascularity of the transferred rib were well documented at 1 week, 1 month, and 6 months postoperatively by radionuclide scintigraphy. It is now 24 months after surgery and the patient began wearing a denture 2 months after the rib transfer. She underwent a split-thickness skin graft vestibuloplasty and floor-of-the-mouth lowering 12 months following the rib transfer with improvement in her denture-wearing capabilities, which has remained constant for 10 months. Vertical resorption of the graft at 3 months was 10 percent, at 6 months 15 percent, and it has stabilized at 25 percent.     

Craniofacial onlay bone grafting: a prospective evaluation of graft morphology, orientation, and embryonic origin

A prospective study using 46 young adult New Zealand rabbits was designed to evaluate onlay bone grafts to the craniofacial skeleton with respect to embryonic origin (membranous or endochondral), gross morphology (unicortical or bicortical), and orientation (cortex-to-bed relationship). Quantitative and qualitative data were analyzed and contrasted at both periods of evaluation (1.5 and 3.0 months). The embryonic origin of onlay bone grafts to the rabbit snout is significantly correlated with graft surface area, volume, weight, and recipient bed union for up to 3 months postoperatively. Over this interval, membranous bone (calvaria) grafts either persist in their entirety or increase, whereas endochondral bone (iliac) grafts resorb. Neither the number of cortices (unicortical or bicortical) nor the orientation of unicortical grafts (cortex-to-bed relationship) affected graft fate regardless of embryonic origin. Bone density remained unaltered during both resorption and deposition. Osteogenesis, demonstrated by serial fluorochrome markers, occurs in both membranous and endochondral bone grafts. Histologically, bone grafts of membranous and endochondral origin differ greatly in their cortical to cancellous diploe ratios and architectural configuration. We hypothesize that the differences found are related to the three-dimensional osseous architecture rather than to the embryonic origin of bone per se.     

Lengthening of a single-loop tibialis tendon graft construct after cyclic loading: a study using Roentgen stereophotogrammetric analysis

Although single-loop tibialis tendon allografts have increased in popularity owing to their many advantages over patellar tendon and double-loop hamstring tendon autografts, some percentage of the patient population do not have clinically stable knees following anterior cruciate ligament reconstruction with single-loop tibialis tendon allografts. Therefore, it would be advantageous to determine the causes of increased anterior laxity which ultimately must be traced to lengthening of the graft construct. One objective of this study was to demonstrate the feasibility of using Roentgen stereophotogrammetric analysis (RSA) to determine the causes of lengthening of a single-loop graft construct subjected to cyclic loading. A second objective was to determine which cause(s) contributes most to an increase in length of this graft construct. Radio-opaque markers were inserted into ten grafts to measure the lengthening at the sites of the tibial and femoral fixations and between the sites of fixation. Each graft was passed through a tibial tunnel in a calf tibia, looped around a rigid cross-pin, and fixed to the tibia with a Washerloc fixation device. The grafts were cyclically loaded for 225,000 cycles from 20 to 170 N. Prior to and at intervals during the cyclic loading, simultaneous radiographs were taken. RSA was used to determine the three-dimensional coordinates of the markers from which the lengthening at the sites of fixation and between the sites of fixation was computed at each interval. The sites of the femoral and tibial fixations were the largest contributors to the increase in length of the graft construct, with maximum average values of 0.68 and 0.55 mm, respectively, after 225,000 cycles. The graft substance between the sites of fixation contributed least to lengthening of the graft, with a maximum average value of 0.31 mm. Ninety percent of the maximum average values occurred before 100,000 cycles of loading for the largest contributors. RSA proved to be a useful method for measuring lengthening due to all three causes. Lengthening of the graft construct at the sites of both fixations is sufficiently large that the combined contributions may manifest as a clinically important increase in anterior laxity.     

In situ splitting of a rib graft for reconstruction of the orbital floor.

A technique of in situ split rib graft harvest is described. It has been used in bone graft reconstructions of the orbital floor when small, thin, malleable grafts are desired. The advantages of in situ rib harvest are technical simplicity, diminished risks of known rib harvest-associated complications, and avoidance of the risks involved with in situ split cranial bone harvesting.     

A new strategy of fingertip reattachment: sequential use of microsurgical technique and pocketing of composite graft

Many methods have been used to reattach amputated fingertips. Of these methods, microsurgery has been accepted as the procedure of choice because the defining characteristic of a microsurgically replanted finger is that its surival in the recipient bed is predicated on functioning intravascular circulation. Although considerable progress has been made in the techniques for microvascular replantation of amputated fingers, the replantation of an amputated fingertip is difficult because digital arteries branch into small arteries. This is in addition to digital veins that run from both sides of the nail bed to the median dorsal sides, which are difficult to separate from the immobile soft tissue. Furthermore, even with the most technically skilled microsurgeon, replantation failure often occurs, especially in severe injury cases. Therefore, the technique is not the only protection against failure, and a new strategy of fingertip reattachment is needed. From March of 1997 to December of 1999, 12 fingers of 11 patients with zone 1 or zone 2 fingertip amputations that were reattached microsurgically but were compromised were deepithelialized, reattached, and then inserted into the abdominal pocket. All had been complete amputations with crushing injuries. Approximately 3 weeks later, the fingers were depocketed and covered with a skin graft. Of the 12 fingers, 7 survived completely and 3 had partial necrosis on less than one-third the volume of the amputated part. The complete survival rate was approximately 58 percent. The results of the above 10 fingers were satisfactory from both functional and cosmetic aspects. The authors believe that this high success rate was achieved because the deepithelialized finger pulp was placed in direct contact with the deep abdominal fascia, which was equipped with plentiful vascularity, not subcutaneous fat. In addition, the pocketing was performed promptly before necrosis of the compromised fingertip occurred. From the results of this study, it is clear that this new method is useful and can raise the survival rate of an amputated fingertip.     

Expanding the limits of composite grafting: a case report of successful nose replantation assisted by hyperbaric oxygen therapy

A successful nose replantation assisted by hyperbaric oxygen therapy is presented, with a brief discussion of the possible mechanisms and a brief literature review of the use of hyperbaric oxygen in tissue preservation and replantation. Although it is not certain that the hyperbaric oxygenation ensured the survival of the replanted nose in this 2-year-old girl, there was documented change in graft appearance during the initial hyperbaric oxygen treatment. A 1-month, 1-year, and 2-year follow-up is included.     

Surgical correction of the severely deviated nose by extramucosal excision of the osseocartilaginous septum and replacement as a free graft

Twenty-five patients with severe internal and external deviation of the nose characterized by deviation of the septum in several planes and almost total obstruction of the airway on one or both sides were operated on. The entire bony and cartilaginous septum was removed in each of these patients, preserving the mucoperichondrial and mucoperiosteal flaps. The extramucosal technique of septal dissection was used. A support graft was fashioned from cartilaginous remnants of the septal cartilage and placed between the mucoperichondrial flaps as a free graft. All patients were followed for a minimum of 1 year. The longest follow-up is 15 years. Aesthetic improvement of the nose was obtained in all patients. All patients experienced varying degrees of improvement in nasal blockade.     

Association of a synthetic bone graft and bone marrow cells as a composite biomaterial

Porous calcium phosphates have osteoconductive properties. The aim of this study was to obtain synthetic calcium phosphate bone graft substitute. X-ray diffraction was employed to investigate the formation of the beta-tricalcium phosphate (β-TCP) phase. We evaluated the effects of bone marrow on the osteoconductivity and mechanical properties of synthetic bone graft (SG). SG cylinders loaded with bone marrow (SGBM) and SG alone were implanted into rabbits femoral condyle bone defects. Histological examinations revealed the resorption of the SG, trabecular bone with osteoblasts and osteoid substance around the implants, and colonization inside the porous β-TCP by newly formed bone. Histomorphometry conducted after three months revealed the osteoid surface to be higher in SGBM than SG (p < 0.05). The compressive strengths of SG and SGBM were significantly higher than the anatomic control at all time periods. The elastic modulus of SBG and SGBM became weaker after implantation. The present results indicate that gB-TCP is a good matrix for bone marrow, which contributes osteoinductive properties in an orthotopic. The composite biomaterial may be useful in reconstructive bone surgery.     

Bioindication: a short review on the use of plants as indicators of heavy metals

This paper discusses some fundamental principles of bioindication. The presentation follows a classification of methods based on the different levels of organization implied in the various approaches. Special references are made to plants that accumulate heavy metals.     

Biosynthesis of Riboflavine in Saccharomyces cerevisiae: the Role of Genes rib1 and rib7

Haploid strains of Saccharomyces cerevisiae with mutations in two different rib genes were constructed. These strains were studied by tetrad analysis and by quantitative determination of accumulation products. The genes rib(1), rib(7), and rib(2) are not linked to each other. rib(1)-rib(7) strains and rib(1)-rib(2) strains exhibit the phenotypic properties of rib(1) strains. rib(7)-rib(2) strains show the phenotypic properties of rib(7) strains. The results support the conclusion that the genes rib(1) and rib(7) code for the first and second enzyme of the riboflavine pathway, respectively.     

A simple technique for reconstruction of the umbilicus, using a conchal cartilage composite graft

A simple technique to reconstruct the umbilicus is reported in which a conchal cartilage composite graft, such as that used in tragus construction in the treatment of microtia, was employed with a very satisfactory result.     

Reconstruction of the maxilla with a double musculoperiosteal flap in connection with a composite calvarial bone graft

A new technique is shown for a one-stage reconstruction of the mucosa of the floors of the nose and maxillary sinus, the bone structures of the maxilla and the hard palate, as well as the mucosal layers of the hard and soft palates and vestibulum. To accomplish this coverage, a vascularized calvarial bone graft with temporal muscle from one side is combined with a vascularized temporal muscle flap from the other side to achieve a three-layer "sandwich" plasty. The advantage of this procedure is reconstruction of the complete maxillary defect with the possibility of denture rehabilitation and the avoidance of oronasal fenestration. Besides the possible complication of insufficient vascularization of the bone and muscle grafts, the donor defect in the calvarial bone and the missing muscle for mastication are to be considered.