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A clinical evaluation of resorbable hydroxylapatite for the repair of human intra-osseous defects.

One of the goals of periodontal therapy is actual hard- and soft-tissue regeneration or at least the functional repair of periodontal defects. Alloplastic materials used in the past included dense hydroxylapatite grafts which were non-resorbable and often exfoliated. A new resorbable hydroxylapatite biomaterial [OsteoGen (HA RESORB)] was used during flap surgery. After the usual initial therapy, full-thickness flaps were elevated. A through debridement of the roots and osseous defects was accomplished. The defects were measured and then filled with OsteoGen. The mean initial bone defect depth was 4.47 mm. These defects were re-evaluated by the probing of bone levels after a 4-6-month healing period. A mean of 2.26 mm of new bone fill was obtained. This represents an average fill of 51%. Seventeen of the 22 defects had 42% or more actual new bone fill. No foreign body reaction or exfoliation occurred.

Alveolar Bone Loss↗

Maturation of composite ligament.

A variety of synthetic fibrillar ligaments are being developed and clinically investigated. The tissue response to the variety of polymeric fibrils is similar. The soft-tissue response to carbon fiber braid substituting for lateral collateral ligament in three human knees and for the anterior cruciate ligament in one was examined 12-42 months after surgery. An advanced stage of maturity of the composite structure was particularly evident by dense bundles of collagen in one of the collateral ligaments and in the substitute for the anterior cruciate ligament. Associated with the newly formed collagen the carbon fibril initially formed unique carbon collagen of composite structural units. Eventually, subsidence of the fibroblast response was accompanied by an increase in density and width of the collagen fibers and by a loss of the configuration of the carbon-collagen units. Even the mature collagenous structure was not comparable to the natural ligament.

Adult↗

The Tikhoff-Linberg procedure: report of ten patients and presentation of a modified technique for tumors of the proximal humerus.

The Tikhoff-Linberg resection is a limb-sparing surgical option to be considered for bony and soft-tissue tumors in and around the proximal humerus and shoulder girdle. Careful selection of patients whose tumor does not involve the neurovascular bundle in the axilla is required. The distal clavicle, upper humerus, and part or all of the scapula are resected. The tumor remains covered by the deltoid muscle plus portions of the muscles that arise from or insert into the resected specimen. In patients with tumors of the proximal humerus a custom prosthesis is used to maintain length and stabilize the distal humerus. Elbow flexion plus stability of the shoulder without the need of an orthosis may be achieved with muscle transfers. Function of the hand and forearm after Tikhoff-Linberg resection should be near normal. Review of results in 10 patients shows no local recurrences and excellent function. The major postoperative problem was nerve palsy. The Tikhoff-Linberg procedure should continue to be used for limb salvage in selected patients with tumors in or around the shoulder girdle.

Adolescent↗

The internal oblique-iliac crest osseomyocutaneous free flap in oromandibular reconstruction. Report of 20 cases.

Microvascular free tissue transfer techniques using composite flaps are the most reliable method for the combined bone and soft-tissue reconstitution of oromandibular defects. Functional oromandibular reconstruction requires that maximum tongue mobility be achieved along with dental prosthetic rehabilitation. The internal oblique-iliac crest osseomyocutaneous microvascular free flap was used in 20 patients for oromandibular reconstruction. The internal oblique muscle, based on the ascending branches of the deep circumflex iliac artery and vein, was used to resurface mucosal defects of the oral cavity and pharynx. The iliac bone, because of its length, width, and natural contour, is the best source of vascularized bone for mandibular reconstruction. The improved soft-tissue component of this composite flap markedly improved the functional results. Reconstruction failed in one patient. Eleven patients underwent dental rehabilitation with either a tissue-borne or osseointegrated implant-borne denture. Follow-up of longer than one year showed minimal donor site morbidity.

Adult↗

Soft-tissue response to total hip surface replacement.

Tissue reaction to prosthesis wear debris and its relationship to prosthetic loosening was investigated. Eighteen dogs underwent hip surface replacement; 6 animals accounted for 6 control and 6 carbon hips, and 13 experimental animals accounted for 13 implanted carbon and 13 cobalt-chromium-molybdenum (CoCrMo) prostheses. Both kinds of prostheses articulated against a high-density polyethylene acetabular component. One year after implantation, tissue response to the prostheses was evaluated according to a semiquantitative method, and a total tissue score indicating the degree of tissue response was obtained. The total tissue score was then compared with the normalized final vertical ground reaction force (GRF) for each hip in the animals with bilateral hip replacements. Compared with the controls, significantly greater tissue response was seen in both kinds of prosthetic hips (p = .001). No statistically significant difference in the tissue response of the two types of hip prostheses was noted, although the tissue response score of the CoCrMo demonstrated a trend toward more severe reaction than the carbon. No statistical difference in tissue reaction was noted for loosened components as compared with tightly fixed components. Amount of wear debris was the best predictor of component loosening. Gait analysis demonstrated a statistically significant negative correlation between GRF and total tissue score (p = .036), and between GRF and wear debris score (p = .034). The results of this study suggest that GRF may predict the amount of wear debris in the tissues surrounding a total hip surface arthroplasty, and that severity of pain is related to the degree of tissue response.

Animals↗

[A new material for frontal sling operation in congenital ptosis].

Congenital ptosis with poor levator function is mainly treated by frontalis suspension. Of all the different suspensory materials tried, autologous fascia lata has been found to offer the most advantages. After the new Gore-tex soft-tissue patch had been used successfully in lid, lacrimal and orbital surgery it was tried with the frontalis suspension technique. When using Gore-tex strips it is not necessary to obtain fascia lata, which is especially difficult in children. A tight connection between the upper lid and the frontalis muscle can be achieved by ingrowth of connective tissue into the PTFE suspensory material. The frontalis muscle then lifts the upper lid. In spite of this, complete lid closure is possible. The surgical results are very satisfactory and are presented in this paper.

Adult↗

Analysis of silicon in human breast and capsular tissue surrounding prostheses and expanders.

Diffusion of polydimethylsiloxane from silicone breast prostheses and soft-tissue expanders has been associated with capsular contraction. We used electron dispersive x-ray analysis and scanning electron microscopy to assess the presence of silicon in capsular tissue surrounding three categories of breast prostheses and expanders. Breast and subcutaneous tissues external to the capsules were used as control specimens. Semiquantitative results allowed capsules to be ranked according to implant type. Silicon was localized within the inner 2.0 mm of capsular tissue. The analyses of tissues from 2 patients exhibiting unilateral, Baker grade IV contraction after bilateral placement of prostheses showed less silicon present in the severely contracted capsule than in the less-contracted capsule. Results from this study diminish the importance of silicon as the initiator of capsular contraction.

Breast Diseases↗

Repeated skin expansion to resurface a massive thigh wound.

We report here a patient who sustained posttraumatic skin and soft-tissue loss of the right thigh. Replacement of approximately 750 cm2 of split-thickness skin graft with adjacent skin serially expanded and advanced demonstrates the applicability of this technique to cover large tissue defects. Despite infection and exposure, we believe that expansion can proceed safely on an outpatient basis, providing that systemic toxicity does not develop and the exposure does not mechanically preclude expansion.

Child↗

Use of the temporary soft-tissue expander in posttraumatic alopecia.

Use of temporary soft-tissue expansion in five patients with posttraumatic alopecia and one patient with congenital alopecia is presented. Indications, operative technique, results, and complications are discussed. It is recommended that transpositional and free scalp flaps be expanded prior to transfer, and it is shown that to achieve greater expansion secondarily, the expanders can be reinserted and the scalp reexpanded as needed. The expansion technique provides a quantity of tissue of similar color, texture, and hair-bearing qualities for reconstruction of adjacent defects and makes secondary reconstruction of donor sites unnecessary. After a minimum follow-up of at least 1 year in each case presented, we have determined that the method is safe, simple, and reliable and provides excellent aesthetic results and high patient acceptance and satisfaction.

Adolescent↗

Chest-wall deformity following soft-tissue expansion for breast reconstruction.

We have presented a case in which the presumed pressure effects of tissue expansion caused multiple nondisplaced rib fractures of the anterior thorax in a patient undergoing breast reconstruction. Although the deformity was severe, a satisfactory cosmetic result was obtained and there have been no clinically significant sequelae during a 1-year follow-up period. The degree of bony deformation was most likely enhanced by the combination of this patient's severe osteoporosis, chronic steroid use, and peripheral vascular disease. The fragility and ease of fracture in the bones of osteoporotic postmenopausal females and the long-term effects of steroids on tissues is well known. We believe this observation to be important, since many reconstructed patients are postmenopausal and have variable degrees of osteoporosis. Many undergo adjuvant chemotherapy with steroids and antihormonal agents, and this group of women may therefore be at a greater risk for the occurrence of pressure deformities. The incidence and long-term significance of such deformities are not known. The reconstructive surgeon should be alert to the possibility of this phenomenon occurring as a result of tissue expansion in the patient with severe osteoporosis, peripheral vascular disease, or chronic steroid use.

Breast↗

Soft-tissue expansion in the lower extremities.

Soft-tissue expansion enjoys ever-wider use, but to date an experience using this technique in the lower extremity has never been presented. We reviewed our first 16 patients to describe the indications and contraindications for the use of tissue expansion in the lower extremity. Guidelines evolved from study of the data. Soft-tissue expansion merits consideration for coverage of problem wounds, in preparation for removal of large benign lesions, and for the repair of contour defects. The operator should know that an open wound below the knee predicts a complication if soft-tissue expansion is attempted in that location. In the thigh, incisions can be confidently placed at the edge of the defect. In every location, large expanders should be chosen so that they are as long as or longer than the adjacent defect. The increase in circumference of the limb should be followed. Simple designs for advancement flaps usually work well. As our experience has grown, reconstruction using soft-tissue expansion in the lower extremity has become safer and the results more predictable through better patient selection and diligent monitoring of intraluminal pressures, even if only by ensuring that the patient is always comfortable. Soft-tissue expansion has a role in reconstruction of the lower extremity.

Adolescent↗

Dermal and epidermal response to soft-tissue expansion in the pig.

To evaluate the dermal and epidermal response to soft-tissue expansion in the pig, round tissue expanders were placed dorsally under tattooed patterns and inflated over 6 weeks. Surface area, skin thickness, histologic changes, and collagen content were evaluated at 6-week intervals. Epidermal thickening and dermal thinning were observed. Dermal thinning persisted 36 weeks after expansion. Dermal collagen content was decreased, although collagen density remained unchanged. Total collagen content calculated within an expanded square grid increased. These data support a theoretical gain in the dermal layer as well as epidermal layer in response to tissue expansion.

Animals↗

Use of a calf prosthesis and tissue expansion in aesthetic reconstruction of the leg.

We present a technique for reconstruction of the legs in patients with soft-tissue loss and formation of large scars with retraction of this tissue in the pretibial region. In such patients, a subcutaneous tissue expander is placed in the region adjacent to the scar tissue. With expansion, we obtained sufficient skin for use in the reconstruction, and the resulting asymmetry in leg diameter was compensated for by means of one or two calf prostheses, depending on the patient.

Adult↗

Midfacial osteotomies in patients with cleft lip, alveolus and palate.

Surgical/orthodontic strategies in patients with hypoplastic midfaces and cleft of lip, alveolus and palates after completion of skeletal growth are guided by cephalometric data, with the soft-tissue profile playing the most important role. The Le Fort I, the extended Le Fort I and, less frequently, the Le Fort II procedure depend on the extent of midfacial hypoplasia. Osteotomy planning should consider that in cleft patient's maxilla, the anterior nasal spine and A-point need to be advanced and caudally rotated to a larger extent than is necessary in non-cleft patients. A slight overcorrection of ANB-angle is necessary to achieve a harmonious and attractive soft-tissue profile since upper lip and nasal soft tissue require more bony support. In severe bimaxillary disturbances the midfacial advancement has to be combined with mandibular osteotomies. Stabilization after midfacial osteotomies should be done by corrosion-resistant Vitallium or titanium miniplates. This technique provides sufficient stability to restore early function immediately after surgery. Intermaxillary fixation following surgery is no longer necessary. Several decisive advantages are provided by this technique over the previously applied wire suspension concepts or wire suturing techniques. The most advantageous points are: No intermaxillary fixation is required immediately postoperatively; Normal soft food intake is resumed after 8-10 days when wound healing is completed; Rigid plate fixation leads to a considerable improvement in bone healing, while 'pumping-effects' induced by micromovements from the masticatory muscles are avoided; Plate fixation allows immediate functional 'antirelapse-treatment' against relapse tendencies, using functional treatment by means of soft intermaxillary elastics.

Adolescent↗

Ultrasonographic measurement of the soft-tissue of the upper jaw.

For preimplantation diagnoses, various mechanical methods for measuring the width of the soft tissue and thus measuring indirectly the osseous bed of the implant can be used. The ability to determine soft tissue thickness above the jaw by ultrasound was evaluated in 8 autopsy specimens. The data obtained were compared with findings from the needle measurement method which is usually employed in clinical practice. The ultrasound measurement method produced realistic data in all sectional planes chosen.

Anthropometry↗

Induction of new-bone formation in the host bed by human bone-tumor transplants in athymic nude mice.

UNLABELLED: Specimens of twelve osteosarcomas, five chondrosarcomas, one giant-cell tumor, and five extraskeletal soft-tissue sarcomas were transplanted into male athymic nude (nu/nu) mice. Survival of the transplant was determined by the volume-doubling time and the sex chromatin of the tumor cells obtained from two female patients. By these criteria and the similarity of the histological composition of the original tumor and the transplant, survival occurred in four of twelve osteosarcomas and four of five chondrosarcomas. Without any local infiltration of lymphocytes or plasma cells, or other evidence of cell-mediated immunity, the surviving tumors regressed by the fourth week after the operation. Transformed osteoblasts and osteoprogenitor cells were replaced by fibrous connective tissue or fibrogenic tumor-tissue cells. Osteocytes degenerated and disappeared from the lacunae. The one giant-cell tumor transplant survived, growing very slowly, but by the end of the first week after transplantation whorls of mononucleated cells appeared in sites previously occupied by multinucleated cells. Transplants of leiomyosarcoma, liposarcoma, and synovioma (one tumor of each) degenerated. One of two fibrosarcomas survived transplantation. The most striking reaction of the mouse host bed was to encompass six of twelve osteosarcomas and four of five chondrosarcomas in deposits of normal living cartilage, bone, and bone marrow. The incidence of new bone inducedy by living transplants was only slightly greater than by implants of freeze-dried killed osteosarcoma tissue. Not one of five extraskeletal sarcomas, living or dead, induced bone formation. These observations suggest that an osteoinductive agent is transmitted by some osteosarcomas and chondrosarcomas. This agent initiates differentiation of host mesenchymal cells into normal non-tumorous cartilage and bone, which later colonized by bone marrow. CLINICAL RELEVANCE: Our observations present experimental evidence of the origin of the envelope of normal non-tumorous bone that may surround tumorous bone. In 1926, Phemister recognized the clinical significane of this envelope as a pitfall in the differential diagnosis of malignant bone tumors, chondrosarcoma, myositis ossificans circumscripta, and other neoplasms. He emphasized the importance of examining the entire specimen for the distribution of deposits of tumorous and normal bone. The induction of normal bone formation in the host bed surrounding transplants of osteosarcomas and some chondrosarcomas (but not transplants of fibrosarcoma, liposarcoma, or leiomyosarcoma) is evidence of a specific tumor-cell characteristic. Thus, the bone inductive response is not an unspecific reaction to injury from expansion or of tumor growth but a biological response to tumor-cell products. Transplants of human malignant tumors growing in the thymus-deficient mouse can be treated by combinations of radiation, amputation, and new chemotherapeutic agents...

Adolescent↗

Biologic response to uncemented Madreporic canine hip arthroplasty.

The Madreporic hip arthroplasty has provided encouraging clinical results. The surface of the prosthesis is unlike other uncemented prostheses since the rough surface is formed by multiple 1-mm diameter beads that are cast as an integral part of the prosthesis and increase its surface area four times. Seven Madreporic hip arthroplasties were implanted in adult male mongrel dogs. Specimens were harvested 5, 6, 9, 12, 20 and 52 weeks after insertion. One specimen became septic and loosened. The prosthesis was stabilized initially by friction fit between the prosthesis and the endosteal cortex of the proximal femur. Dense, uniformly organized, fibrous tissue surrounded the prosthesis at 5 weeks. The fibrous tissue appeared similar to Sharpey's fibres. Circumferential bone contact increased from 26% at 5 weeks to 60% at 52 weeks. Fluorescent labelling revealed active new bone formation within the interstices of the prosthesis without evidence of an intervening soft-tissue membrane. Firm mechanical anchorage of the Madreporic femoral prosthesis was demonstrated in this study.

Animals↗