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Prevention of major amputations in nonischemic lower limb lesions.

BACKGROUND: Major lower limb amputations continue to be performed at an increasing rate, the major cause being the rising prevalence of adult onset diabetes. It can be demonstrated that a reduction in amputation rate can be achieved at institutes with a higher level of academic and specialty interest, by avoiding errors of management and by newer technical innovations in wound closure. STUDY DESIGN: A simpler method of wound closure that is easily taught and learned and is readily available to the medical community and the patient population can play a substantial role in reducing the number of amputations. Satisfactory closure of open lesions by full-thickness skin and subcutaneous tissue carries with it a lower incidence of recurrence, reduces costs by avoiding or reducing length of hospitalization, and minimizes use of general anesthesia, a serious matter in immunocompromised older patients. Avoiding errors of technique will additionally reduce amputation rate. RESULTS: In the last 10 years, 125 patients, mostly diabetic and elderly, with major and recurrent lesions of the lower extremities, have been treated by closure of the debrided wound with a combination of external tissue expansion and wound toilette. Major lower limb amputations have been avoided. CONCLUSIONS: Experience confirms that the relationship between high hospital volume, specialty interest, higher level of academic care; avoiding technical errors; and simplifying the methodology, lead to a reduction in need for major amputations. A lower mortality in the patient population at risk is achieved and a reduction in costs, which have risen beyond the 132 billion dollars level, can be expected.

Adult↗

A new partly external device for extension of skin before excision of skin defects.

Tissue expansion is a well established method for reconstructive surgery. As a complement, a new technique of skin extension has been developed, and tested clinically. The device consists of two holding bars with several straps placed between them, which usually is applied under local anaesthesia. It is an efficient, rapid, and inexpensive way of expanding skin before excision of skin defects. Thirty-two patients have been treated, three patients have had complications, and length of follow up ranged from 2-12 months.

Dermatologic Surgical Procedures↗

Expanded full-thickness skin grafts in children: case selection, planning, and management.

Since our initial presentation of our experience with tissue expansion as a means of harvesting large full-thickness skin grafts in children in 1987, we have continued to "expand" both the size of full-thickness skin grafts harvested and the range of reconstructive problems to which we have applied the technique. Sixteen expanded full-thickness grafts have been used for immediate reconstruction following giant nevus excision and in postburn reconstruction. Patients ranged in age from 6 months to 15 years, with follow-up ranging from 6 months to 6 1/2 years. Grafts ranging in size from approximately 60 cm2 (excluding the dimensions of one submental graft) to greater than 700 cm2 were harvested from expanded donor sites on unilateral or bilateral groin/lower abdomen, clavicular, and a single submental expansion. Five expanded full-thickness grafts were used in facial reconstruction for single aesthetic unit coverage, multiple unit, and one single-sheet full facial graft. One expanded full-thickness graft was used on the breast. Three grafts were used in dorsal hand and finger coverage, and seven were used on the lower extremity, including an entire plantar surface and toes. Graft loss was confined to a 6.25-cm2 area on one cheek in the full facial expanded full-thickness grafts and a 9-cm2 area on the non-weight-bearing area of the full plantar graft. Donor-site complications were negligible. The anatomic confines of the donor sites and size of the patient may require expander replacement (in situ serial expansion) in order to obtain a large enough graft and accomplish primary donor-site closure. Expander and injection port placement in children for ease of injection and planned expander change must be anticipated. Our protocol from preoperative teaching through graft take is reviewed. Experience has demonstrated that expanded full-thickness grafts maintain all the characteristics of non-expanded full-thickness skin grafts and are an excellent reconstructive option in children.

Adolescent↗

Complex abdominal wall reconstruction: a comparison of flap and mesh closure.

OBJECTIVE: To analyze a series of patients treated for recurrent or chronic abdominal wall hernias and determine a treatment protocol for defect reconstruction. SUMMARY BACKGROUND DATA: Complex or recurrent abdominal wall defects may be the result of a failed prior attempt at closure, trauma, infection, radiation necrosis, or tumor resection. The use of prosthetic mesh as a fascial substitute or reinforcement has been widely reported. In wounds with unstable soft tissue coverage, however, the use of prosthetic mesh poses an increased risk for extrusion or infection, and vascularized autogenous tissue may be required to achieve herniorrhaphy and stable coverage. METHODS: Patients undergoing abdominal wall reconstruction for 106 recurrent or complex defects (104 patients) were retrospectively analyzed. For each patient, hernia etiology, size and location, average time present, technique of reconstruction, and postoperative results, including recurrence and complication rates, were reviewed. Patients were divided into two groups based on defect components: Type I defects with intact or stable skin coverage over hernia defect, and Type II defects with unstable or absent skin coverage over hernia defect. The defects were also assigned to one of the following zones based on primary defect location to assist in the selection and evaluation of their treatment: Zone 1A, upper midline; Zone IB, lower midline; Zone 2, upper quadrant; Zone 3, lower quadrant. RESULTS: A majority of the defects (68%) were incisional hernias. Of 50 Type I defects, 10 (20%) were repaired directly, 28 (56%) were repaired with mesh only, and 12 (24%) required flap reconstruction. For the 56 Type II defects reconstructed, flaps were used in the majority of patients (n = 48; 80%). The overall complication and recurrence rates for the series were 29% and 8%, respectively. CONCLUSIONS: For Type I hernias with stable skin coverage, intraperitoneal placement of Prolene mesh is preferred, and has not been associated with visceral complications or failure of hernia repair. For Type II defects, the use of flaps is advisable, with tensor fascia lata representing the flap of choice, particularly in the lower abdomen. Rectus advancement procedures may be used for well-selected midline defects of either type. The concept of tissue expansion to increase both the fascial dimensions of the flap and zones safely reached by flap transposition is introduced. Overall failure is often is due to primary closure under tension, extraperitoneal placement of mesh, flap use for inappropriate zone, or technical error in flap use. With use of the proposed algorithm based on defect analysis and location, abdominal wall reconstruction has been achieved in 92% of patients with complex abdominal defects.

Abdominal Muscles↗

[The technical safety of tissue expander domes].

UNLABELLED: Since leakage of an expander dome is a well-known complication that may lead to interruption of a tissue expansion procedure, the aim of this project was to study different expansion domes in relation to a medication port after perforation with various needles. MATERIAL AND METHODS: The combinations of five different expansion domes and one medication port were tested with three different needle types having two different diameters. The force-distance curves during puncturing, the puncture forces required and the leakage opening pressures were measured after single on repeated punctures with small and large forces. A total of more than 2000 experiments were performed. RESULTS: Only one of the expander domes and the medication port had sufficient pressure stability. The technical characteristics of these devices are presented. However, the different needle types and puncture techniques had only a minor influence on the pressure stability of the expander domes.

Catheters, Indwelling↗

Labial skin-flap vaginoplasty using tissue expanders.

In severe vaginal malformations, when the distance between the upper vaginal pouch and perineum is too long (6 cm or more), reconstruction of the vagina can be performed by colonic interposition or by long cutaneous flaps obtained by the tissue expansion technique. Two female adolescents were treated using expanded labial skin flaps. Dissection and anastomosis between the vaginal remnant and cutaneous tube was performed by the transtrigonal approach. Results were satisfactory at 2.5-year follow-up. In our opinion, expanded labial skin-flap vaginoplasty has three main advantages: (1) it permits the construction of a large, soft, well-vascularized neovagina using non-hair-bearing labial skin; (2) it obviates postoperative dilations and prevents delayed strictures; and (3) a transtrigonal approach permits an easy vaginal dissection and a careful, tension-free anastomosis.

Adolescent↗

Staged sequential reconstruction of a total lower lip, chin, and anterior mandibular defect.

The combination of a total lower lip, chin, and anterior mandibular defect following cancer resection is an extremely complex problem that requires a sequence of operations to optimize functional and aesthetic results. One patient is presented in whom the defect was reconstructed with a free fibular flap followed by a series of ancillary procedures using both modern and traditional techniques. At the time of tumor ablation, the through-and-through oromandibular defect was reconstructed with a fibular osteocutaneous flap. The lower lip and gingivolabial sulcus was reconstructed later with a tongue flap. Tissue expansion was subsequently used to replace the fibular skin with expanded submental hair-bearing skin. A polyethylene implant was added later to the fibular bone for chin augmentation. Subsequently the lower lip was supported with a tendinous graft suspended to the anterior masseter bilaterally. Lastly, the vermilion border was elevated by removing a rim of the tongue flap and covering the secondary wound with a full-thickness skin graft. At the end of the reconstructive procedures, lip seal and oral aperture were good with no drooling and excellent speech.

Carcinoma, Squamous Cell↗

[Experimental study on rapid expansion of soft tissue].

Nine white pigs weighing about 15 kg were divided into three groups: rapid expansion group (REG), conventional expansion group (CEG) and control group (CON). Expansion was carried out under monitoring of interal pressure of the expander and blood flow of the skin over the expander. After completion of expansion, hemodynamic, physical, histologic and ultrastructure changes of the expanded skin were measured and recorded. The study showed: (1) The immediate retraction ratios of skin of three groups were 41.37%, 20.82% and 10.01%, respectively (P < 0.01). (2) The thickness of the epidermis of the three groups was not statistically different, though the dermis of the expanded skin was thinner than that of the control (P < 0.01). (3) The density of collagen in the dermis of the three groups was 80.57 +/- 5.47, 79.49 +/- 6.31 and 82.72 +/- 2.69, respectively; the density of elastin of the three groups was 2.88 +/- 1.24, 2.77 +/- 0.74 and 2.56 +/- 0.63, respectively (P < 0.05). We concluded that the delay phenomenon of the expanded flap depends mainly on the intensity of expansion. The immediate retraction ratio of the rapidly expanded skin was greater than that of conventionally expanded skin. Rapid expansion also results in tissue hypertrophy but does not cause destruction of collagen. With proper calculating the size of the defect and estimating immediate skin retraction, rapid expansion is feasible in clinical applications.

Animals↗

Quantitative analysis of lidocaine hydrochloride delivery by diffusion across tissue expander membranes.

Permeability of Silastic tissue expander shells to lidocaine was studied to investigate the feasibility of intraluminal lidocaine injection for pain relief during soft-tissue expansion. Both intact expanders and an apparatus using isolated Silastic membrane segments were used to partition solutions of various lidocaine concentrations, and the rate of diffusion was quantitatively measured using a fluorescence polarization immunoassay. Lidocaine flux was found to follow Fick's law of passive diffusion with respect to time, surface area, and concentration gradient for the first 9 hours, with a permeability coefficient of 10.3 +/- 2.6 micrograms (h.cm2.percent)-1 (mean +/- SD) and diffusion coefficient of 7.5 x 10(-7) cm2/min for an average membrane thickness of 473 +/- 23 microns. After 9 hours, the lidocaine flux decreased exponentially, although the concentration gradient across the membrane remained essentially the same order of magnitude. Plasma proteins in the outer bathing solution and methylparaben used as a preservative in the standard lidocaine formulation had no influence on the change in transport flux with time. At the end of the linear portion of the diffusion curve, less than 2 percent of the total intraluminal lidocaine had crossed the membrane. Potential toxicity in the event of implant rupture limits the maximum total lidocaine dose to approximately 500 mg within an expander at any one time. Within these limits, the capacity for lidocaine delivery of 500 mg lidocaine by a 640-cc tissue expander would be only 6 mg during the first 9 hours after administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Diffusion↗

The role of pressure on regulation of craniofacial bone growth.

The regulatory role of pressure on growth and differentiation of the craniofacial skeleton is largely unknown. We devised an experimental model to determine if the graded application of pressure could exert a trophic influence on craniofacial bone, allowing deliberate alteration and reshaping of the facial skeleton. To examine this question, 18 kittens were used to determine the adverse morphological sequelae after orbital evisceration and to compare the ability to remedy such facial deformity with the use of an inert implant or pressure-induced tissue expansion. In addition to detailed craniometric measurements of the cranial, orbital, and midfacial regions, histological analyses as well as radiographic and gross morphological comparisons were evaluated. Our results demonstrate a severe asymmetry and constriction in the orbital and midfacial regions resulting from orbital evisceration in the growing kitten. Placement of an inert implant will help to ameliorate only some of these adverse sequelae, whereas graded application of pressure appears to direct craniofacial bone growth, resulting in normal bony histology and improved facial form. We affirm that regional growth disturbances can alter normal facial development and that the regulatory role of pressure on bone growth can be exploited to dynamically correct abnormal craniofacial anatomy.

Analysis of Variance↗

An audit of outcome including patient satisfaction with immediate breast reconstruction performed by breast surgeons.

Reconstruction of the female breast is becoming ever more frequently requested by patients after mastectomy for cancer. One of the least complex techniques is that of local tissue expansion with a permanent prosthesis. We present our experience and the clinical outcomes of the first 100 patients to have undergone surgery in the 4 years since the introduction of this method of breast reconstruction in our unit. A retrospective study was performed with a detailed questionnaire being sent to each patient for subjective assessment of satisfaction. Data were also collected on the rates of clinical infection of the prosthesis and the need for further surgery, including capsulotomy, nipple reconstruction and contralateral procedures. With 84% expressing their satisfaction at the final result, immediate breast reconstruction is both feasible and highly acceptable to the majority of patients.

Adult↗

Biomaterial properties and biocompatibility in cell culture of a novel self-inflating hydrogel tissue expander.

The aim of this study was to investigate the swelling properties and the biocompatibility of a novel tissue expander material. The self-inflating material is a hydrogel consisting of a modified copolymer of methylmethacrylate and N-vinyl-2-pyrrolidone, which takes up water by osmosis. To increase the swelling volume, the primarily neutral gel material was modified by converting it into an ionized gel. To study the swelling and pressure behavior of the material, the anhydrous gel cylinders were equilibrated in distilled water, saline, and sugar solutions. The biocompatibility was investigated in cell culture. We tested the hydrogel eluate after swelling for cytotoxicity and mutagenicity using the cell lines MRC-5 and P3X63 Ag8 653 (Ag8). Furthermore, particles of the material were added to cell cultures to induce foreign body reactions and to verify its influence on monocyte differentiation. The material has a swelling capacity (Q = maximum swelling volume/anhydrous volume) of 5 to 50 depending on the degree of ionization of the polymer network. In this study, two polymer modifications with a swelling equilibrium of Q = 11.1 and 30 in water were tested. The swelling ratio also depends on concentration and ion content of the equilibration medium. The highest swelling capacity was found in water, the lowest in Ringer's solution. The swelling of the anhydrous material with the swelling capacity of Q = 11.1 fits best the average purpose of material properties for tissue expansion and generates a maximal hydrostatic pressure of approximately 235 mmHg. Effects on cell proliferation were detected only at the highest eluate concentration tested (i.e., eluate: culture medium = 1:1), which was far beyond physiological values, whereas mutagenicity was absent. Monocytes neither migrated nor tightly attached to the hydrogel. They neither phagocytose the material nor did they show any sign of a foreign body reaction, e.g., formation of multinucleated giant cells or monocyte proliferation. In the presence of hydrogel material, the differentiation processes of monocytes to macrophages or dendritic cells, respectively, were found to be undisturbed. From these results, we conclude that there is a high biocompatibility of the expander material, which may be a favorable and interesting candidate for further clinical applications.

Animals↗

Management of gestational gigantomastia.

BACKGROUND: Gigantomastia of pregnancy is a rare, severely debilitating condition characterized by massive enlargement of breasts and resulting in tissue necrosis, ulceration, infection, and, occasionally, hemorrhage. Typically, resolution of breast hypertrophy to near prepregnancy size occurs in the postpartum period. Treatment is controversial. METHODS: The authors present a patient with gestational gigantomastia for whom nonoperative management failed and who subsequently required bilateral mastectomies. In addition, the authors performed a comprehensive review of reported cases and generated a treatment algorithm. RESULTS: The patient tolerated the mastectomies well and went on to deliver a healthy child. Postpartum delayed breast reconstruction with tissue expansion and implant placement yielded good results. The literature review demonstrates that medical management has successfully avoided surgery during gestation in 39 percent of cases since 1968. However, 35 percent of patients eventually underwent breast reduction (12 percent) or mastectomy (88 percent) during pregnancy. Spontaneous or elective termination of the pregnancy accounted for 30 percent of outcomes. Patients who underwent breast reduction and then became pregnant had a 100 percent (four of four patients) chance of recurrence. Two women had mastectomy and subsequent pregnancies. One woman developed multiple small areas of recurrence that were surgically excised. The other woman had two additional pregnancies with no recurrence of symptoms. CONCLUSIONS: Medical therapies to manage gestational gigantomastia are inconsistent in outcome. Since some patients respond, these therapies are worth trying. However, if the patient and/or fetus are experiencing significant morbidity, then surgical intervention is warranted. Breast reduction or mastectomy with delayed reconstruction is the preferred procedure. If the mother is considering future pregnancies, mastectomy offers the lowest risk of recurrence.

Adult↗

Home inflation of tissue expanders: a safe and reliable alternative.

The concept of tissue expansion by the placement of inflatable subcutaneous silicone implants was popularised by Radovan in the late 1970s and is now widely used in clinical practice. After the initial placement of the expander, a series of outpatient visits is required during which the expander is serially inflated. These visits can be very stressful for the patient and are costly in terms of patient transport and clinic time. We present a series of 26 expanders (in eight patients) that were inflated at home by the patient or a relative, and compare the results with those from 30 expanders (in 15 patients) inflated in the outpatient department. The results show that whilst there was a slightly higher incidence of minor infections in the group inflated at home (42% versus 23%, P> 0.05), the overall success rate of the operation was greater in the home-inflation group (96% versus 90%, P> 0.05). However, these differences were not statistically significant. This study provides evidence to support the practice of inflation at home, which is safe, cost effective and less stressful for the patient.

Caregivers↗

Delayed-immediate breast reconstruction.

In patients with early-stage breast cancer who are scheduled to undergo mastectomy and desire breast reconstruction, the optimal timing of reconstruction depends on whether postmastectomy radiation therapy will be needed. Immediate reconstruction offers the best aesthetic outcomes if postmastectomy radiation therapy is not needed, but if postmastectomy radiation therapy is required, delayed reconstruction is preferable to avoid potential aesthetic and radiation-delivery problems. Unfortunately, the need for postmastectomy radiation therapy cannot be reliably determined until review of the permanent tissue sections. The authors recently implemented a two-stage approach, delayed-immediate breast reconstruction, to optimize reconstruction in patients at risk for requiring postmastectomy radiation therapy when the need for postmastectomy radiation therapy is not known at the time of mastectomy. Stage 1 consists of skin-sparing mastectomy with insertion of a completely filled textured saline tissue expander. After review of permanent sections, patients who did not require post-mastectomy radiation therapy underwent immediate reconstruction (stage 2) and patients who required postmastectomy radiation therapy completed postmastectomy radiation therapy and then underwent standard delayed reconstruction. In this study, the feasibility and outcomes of this approach were reviewed. Fourteen patients were treated with delayed-immediate reconstruction between May of 2002 and June of 2003. Twelve patients had unilateral reconstruction and two patients had bilateral reconstruction, for a total of 16 treated breasts. All patients completed stage 1. Tissue expanders were inserted subpectorally in 15 breasts and subcutaneously in one breast. The mean intraoperative expander fill volume was 475 cc (range, 250 to 750 cc). Three patients required postmastectomy radiation therapy and underwent delayed reconstruction. Eleven patients did not require postmastectomy radiation therapy. Nine patients had 11 breast reconstructions (stage 2), six with free transverse rectus abdominis musculocutaneous (TRAM) flaps, one with a superior gluteal artery perforator flap, and four with a latissimus dorsi flap plus an implant. The median interval between stages was 13 days (range, 11 to 22 days). Two patients who did not require postmastectomy radiation therapy have not yet had stage 2 reconstruction, one because she wished to delay reconstruction and the other because she required additional tissue expansion before permanent implant placement. Six complications occurred. The stage 1 complications involved two cases of mastectomy skin necrosis in patients who required post-mastectomy radiation therapy; one patient required removal of the subcutaneously placed expander before postmastectomy radiation therapy and the other patient had a subpectorally placed expander that only required local wound care. The stage 2 complications were a recipient-site seroma in a patient with a latissimus dorsi flap, a recipient-site hematoma in the patient with the superior gluteal artery perforator flap, and two arterial thromboses in patients with TRAM flaps. Both TRAM flaps were salvaged. Delayed-immediate reconstruction is technically feasible and safe in patients with early-stage breast cancer who may require postmastectomy radiation therapy. With this approach, patients who do not require postmastectomy radiation therapy can achieve aesthetic outcomes essentially the same as those with immediate reconstruction, and patients who require postmastectomy radiation therapy can avoid the aesthetic and radiation-delivery problems that can occur after an immediate breast reconstruction.

Adult↗

Auricular repair with autogenous rib cartilage grafts: two decades of experience with 600 cases.

The purpose of this paper is twofold: to present a sound approach to auricular construction using methods that have evolved through two decades of my personal experience with 600 cases and to discuss pertinent information I have gleaned from a questionnaire sent to my operated patients. This series comprises 546 completed ears in 500 microtia patients (46 bilateral) and 75 completed ears in acquired deformities. Follow-up ranges from 1 to 17 years. Major complications such as infection, hematoma, or skin loss with cartilage exposure occurred in only 1.6 percent of cases and were limited to the perioperative period of 12 days. None have occurred in the last 9 years (481 frameworks). This paper describes the evolution and rationale for my current management of total ear repair and covers preoperative planning, how to fabricate the rib cartilage framework, how to modify the framework for specific deformities, and how to cover the framework, i.e., how to assess and use local skin and vestiges or when to supplement the coverage by recruiting fascial flaps or using tissue expansion. When considering fascial flaps, patient selection was found to be particularly important because of long-term effects on the donor scalp; expansion was found to be most useful intraoperatively. This paper also covers how to manage the hairline, how to stage the surgery, when to combine procedures, and how to manage bilateral microtia in a team approach. The survey revealed that autogenous cartilage frameworks grow, are durable, retain their detail over the years, and withstand trauma well. More than 40 severe traumas occurred in surgically constructed ears, and all healed without incident. Ears constructed in young patients generally grew to keep pace with the opposite normal side; 41.6 percent actually overgrew by several millimeters. Emotional and psychological benefits were universal, and patient satisfaction was high. Among patients who were classified as "severely affected" by the original deformity, 100 percent were pleased with the result. When considered "moderately disturbed" by the microtic defect and operated on by age 14, 95.5 percent of patients were satisfied with the surgical repair; 83.3 percent of adolescents between the ages of 15 and 20 who did not consider themselves "severely affected" by the deformity were pleased with the outcome, and the rest were "undecided."

Adolescent↗

The 'RITE' use of the Fricke flap in periorbital reconstruction.

PURPOSE: To revisit an important but outmoded periorbital reconstructive technique. We present cases to illustrate the usefulness of the Fricke flap and describe a method of rapid intraoperative tissue expansion (RITE), which can enhance the applicability and effectiveness of the Fricke flap. A comparison between those cases performed with and without adjunctive RITE was not made due to the low numbers available. METHODS: A retrospective review of clinical cases. RESULTS: A total of 20 cases in which the Fricke flap was used for periorbital reconstruction were reviewed. The mean patient age was 64.7 years; the male-to-female ratio was 1:1. The patient follow-up ranged from 1 to 8 years with a mean of 4.2 years. The most common cause (65%) of periorbital defect was excision of eyelid malignancy. Necrosis of the terminal segment of the flap requiring further surgical intervention occurred in 10% (2/20). In both of these cases, the surgeons were trainees, with the complications being due to poor surgical technique. In the first case, the flap base was too narrow and in the second case, the distal end of the flap was thinned excessively. The functional result was excellent in 10/20 (50%), good in 5/20 (25%), fair in 3/20 (15%), and poor in 2/20 (10%). The cosmetic result was excellent in 3/20 (15%), good in 12/20 (60%), fair in 3/20 (15%), and poor in 2/20 (10%). CONCLUSION: The Fricke flap is an important and, in selected cases, an indispensable technique in periorbital reconstruction.

Adult↗

A comparison of the capsules around smooth and textured silicone prostheses used for breast reconstruction. A light and electron microscopic study.

A total of 18 women who had undergone modified radical mastectomy and tissue expansion for breast reconstruction were studied. When the expanders were replaced, nine patients had received smooth, gel-filled permanent prostheses and nine had received textured, gel-filled permanent prostheses. For medical reasons, e.g. capsular contraction, incorrectly placed or sized implant, an additional operation was performed, and then biopsy specimens from the capsules around the prostheses were taken and subsequently examined with the aid of the light and transmission electron microscope (TEM). A histologist was able to classify blindly 11 capsules out of 13 which were investigated by light microscopy in the correct groups and several differences between the capsules were found. Capsules around the smooth implants had a clear line of separation between the inner surface and the prosthesis, and formed a single collageneous layer. They were sparse in fibroblasts, which were long and thin. Capsules around textured implants consisted of two layers, the outer layer being compact with long, slender fibroblasts, and the inner one looking rugged with wavy bundles of collagen often splitting from each other, and with shorter and more rounded fibroblasts. The overall thickness seemed greater compared to the capsules around the smooth prostheses, which, on the other hand, showed a greater variation in thickness. To analyze collagen fibril diameters, sample sections were photographed at magnification 22,000 x in the TEM. The fibril diameters were measured with an interactive image analysis system (IBAS). The mean diameter of the collagen fibrils was 47.2 nm in the capsules around the smooth prostheses and 51.7 nm in the capsules around the textured prostheses.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗