			Home About us Contact

Recipient Site (recipient + site)

Distribution by Scientific Domains

Medical Sciences	87%
Life Sciences	12%

Distribution within Medical Sciences

Dermatology	35%
Implant Dentistry	28%

Selected Abstracts

In Vivo Follicular Unit Multiplication: Is It Possible to Harvest an Unlimited Donor Supply?

DERMATOLOGIC SURGERY, Issue 11 2006
ERGIN ER MD
BACKGROUND Follicular unit extraction is a process of removing one follicular unit at a time from the donor region. The most important limitation of this surgical procedure is a high transection rate. OBJECTIVE In this clinical study, we have transplanted different parts of transected hair follicle by harvesting with the follicular unit extraction technique (FUE) in five male patients. MATERIALS AND METHODS In each patient, three boxes of 1 cm2 are marked at both donor and recipient sites. The proximal one-third, one-half, and two-thirds of 15 hair follicles are extracted from each defined box and transplanted in recipient boxes. The density is determined at 12 months after the procedure. RESULTS A mean of 3 (range, 2,4) of the proximal one-third, 4.4 (range, 2,6) of the proximal one-half, and 6.2 (range, 5,8) of the proximal two-thirds of the transplanted follicles were observed as fully grown after 1 year. At the donor site, the regrowth rate was a mean of 12.6 (range, 10,14) of the proximal one-third, 10.2 (range, 8,13) of the proximal one-half, and 8 (range, 7,12) of the proximal two-thirds, respectively. CONCLUSION The survival rate of the transected hair follicles is directly related to the level of transection. Even the transected parts, however, can survive at the recipient site; the growth rate is not satisfactory and they are thinner than the original follicles. We therefore recommend that the surgeon not transplant the sectioned parts and be careful with the patients whose transection rate is high during FUE procedures. [source]

Impacts of sudden winter habitat loss on the body condition and survival of redshank Tringa totanus

JOURNAL OF APPLIED ECOLOGY, Issue 3 2006
NIALL H. K. BURTON
Summary 1Recent theoretical modelling has provided important insights into how habitat loss may affect local populations through impacts on individual fitness (survival, body condition, fecundity). Despite this, attempts to provide empirical evidence of such impacts on displaced individuals have been limited. Using a before-after-control-impact (BACI) approach, we report how a sudden loss of wintering habitat impacted on the body condition and survival of redshank Tringa totanus. 2The intertidal mudflats of Cardiff Bay, UK, were inundated with freshwater in November 1999 following impoundment by a barrage, resulting in the displacement of c. 300 redshank to adjacent habitat on the Severn Estuary. Movements and the survival of these birds were monitored through observations of colour-marked individuals. Comparative survival rates were calculated for marked populations at the main recipient site, Rhymney, and a control site. 3Displaced redshank had difficulty maintaining their mass in the first winter post-barrage closure: adults previously only recorded at Cardiff Bay were significantly lighter than those previously recorded at Rhymney. 4Survival rates of displaced redshank also declined. The estimated annual survival of adult Cardiff Bay redshank fell from 0·846 in the 2 years pre-barrage closure to 0·778 in the 3 following years because of a significant decline in winter survival (P = 0·0006). In comparison, there was no significant change in the survival of adult Rhymney redshank, and adult survival at the control site was actually greater post-barrage closure than beforehand. The lack of decline in these rates and the similarity between those of Cardiff Bay adults pre-barrage closure and Rhymney adults indicate that the increase in winter mortality of Cardiff Bay birds resulted from their displacement. 5Synthesis and applications. This study provides the first conclusive empirical evidence that habitat loss can impact individual fitness in a bird population. Adult redshank displaced from Cardiff Bay experienced poor body condition and a 44% increase in mortality rate. Without an increase in the recruitment of first-winter birds, such a change is likely to reduce substantially local population size. The results reported here should help to inform governments, planners and non-governmental organizations (NGOs) seeking to understand how developments might impact on animal populations. [source]

The use of suction blisters for recipient site in epidermal grafting: the implications for vitiligo

JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 2 2009
D-Y Lee
[source]

Photoacoustic monitoring of neovascularities in grafted skin

LASERS IN SURGERY AND MEDICINE, Issue 3 2006
Mutsuo Yamazaki MS
Abstract Background and Objective In skin grafting, evaluation of graft adhesion to the recipient site in the early postgrafting period is important. However, conventional diagnoses such as visual observation and thermography required about 1 week to obtain results and these methods cannot give quantitative information on the adhesion of a skin graft. We proposed a new method for monitoring adhesion of grafted skin that is based on measurement of photoacoustic signals. To investigate the validity of the method, we performed experiments using rat autografts models. Study Design/Materials and Methods Grafted skin in a rat was irradiated with 200 µJ, 532-nm nanosecond laser pulses, and photoacoustic signals were detected with a piezoelectric transducer placed on the skin at various postgrafting time. Temporal profiles of the signals were converted to depth profiles using an assumed sound velocity of 1,500 m/second. Histological analysis was performed to observe neovascularities formed in the grafts. Results At 6 hours postgrafting, a photoacoustic signal peak appeared in the depth region corresponding to the graft. The results of histological analysis also showed formation of neovascularities in the graft after 6 hours postgrafting, indicating that photoacoustic signal peaks observed in the graft originated from the neovascularities, which are an indication of graft adhesion. For up to 24 hours postgrafting, no significant difference was observed between the results of visual observation and laser Doppler imaging of the same grafted skins. Conclusion We have demonstrated that photoacoustic signals originating from neovascularities in grafts can be sensitively detected in the early postgrafting period, suggesting the validity of photoacoustic measurement for adhesion monitoring of skin grafts. Lasers Surg. Med. 38:235,239, 2006. © 2006 Wiley-Liss, Inc. [source]

Face resurfacing using a cervicothoracic skin flap prefabricated by lateral thigh fascial flap and tissue expander

MICROSURGERY, Issue 7 2009
Ph.D., Qingfeng Li M.D.
Background: Resurfacing of facial massive soft tissue defect is a formidable challenge because of the unique character of the region and the limitation of well-matched donor site. In this report, we introduce a technique for using the prefabricated cervicothoracic skin flap for facial resurfacing, in an attempt to meet the principle of flap selection in face reconstructive surgery for matching the color and texture, large dimension, and thinner thickness (MLT) of the recipient. Materials: Eleven patients with massive facial scars underwent resurfacing procedures with prefabricated cervicothoracic flaps. The vasculature of the lateral thigh fascial flap, including the descending branch of the lateral femoral circumflex vessels and the surrounding muscle fascia, was used as the vascular carrier, and the pedicles of the fascial flap were anastomosed to either the superior thyroid or facial vessels in flap prefabrication. A tissue expander was placed beneath the fascial flap to enlarge the size and reduce the thickness of the flap. Results: The average size of the harvested fascia flap was 6.5 × 11.7 cm. After a mean interval of 21.5 weeks, the expanders were filled to a mean volume of 1,685 ml. The sizes of the prefabricated skin flaps ranged from 12 × 15 cm to 15 × 32 cm. The prefabricated skin flaps were then transferred to the recipient site as pedicled flaps for facial resurfacing. All facial soft tissue defects were successfully covered by the flaps. The donor sites were primarily closed and healed without complications. Although varied degrees of venous congestion were developed after flap transfers, the marginal necrosis only occurred in two cases. The results in follow-up showed most resurfaced faces restored natural contour and regained emotional expression. Conclusion: MLT is the principle for flap selection in resurfacing of the massive facial soft tissue defect. Our experience in this series of patients demonstrated that the prefabricated cervicothoracic skin flap could be a reliable alternative tool for resurfacing of massive facial soft tissue defects. © 2009 Wiley-Liss, Inc. Microsurgery, 2009. [source]

Hemodynamic alterations in the transferred tissue to lower extremities

MICROSURGERY, Issue 2 2009
Hiroyuki Sakurai M.D., Ph.D.
A higher incidence of failure has been reported for free flaps transplanted to the lower extremities. However, the physiological background of this phenomenon has not been elucidated. We reviewed the 3-day postoperative hemodynamic data for 103 free flaps, including the in situ venous pressure (N = 103), arterial pressure (N = 53), and surface blood flow (N = 42). The cases were divided into two groups based on the recipient site, i.e., lower extremity (the LE group: N = 29) and the other (non-LE group: N = 74). The venous pressure was significantly higher in the LE group (26.6 ± 2.2 vs. 14.8 ± 1.2 mmHg), whereas the arterial pressure immediately after surgery was lower than the non-LE group. The hemodynamic data within the transferred tissues demonstrated significant differences between groups, especially in the early postoperative period. There is a possibility that the high venous pressure may aggravate the poor perfusion in tissues transferred to the lower extremities. © 2008 Wiley-Liss, Inc. Microsurgery, 2009. [source]

The use of integra artificial dermis to minimize donor-site morbidity after suprafascial dissection of the radial forearm flap

MICROSURGERY, Issue 7 2007
Andreas I. Gravvanis M.D., Ph.D.
In an effort to minimize the radial forearm flap donor-site morbidity, the flap was elevated using the suprafascial dissection technique, in six patients with various facial defects. The donor site was covered primarily with Integra artificial skin and secondarily with an ultrathin split-thickness skin graft. The mean time to wound healing of the forearm donor site was 24 days. There were no flap failures, and all flaps healed uneventfully. At the end of the follow-up, all patients showed normal range of motion of the wrist and the fingers, normal power grip, and power pinch. All patients evaluated the esthetic appearance of the forearm donor site as very good. In conclusion, suprafascial dissection of the forearm flap creates a superior graft recipient site, and the use of Integra artificial dermis is a valuable advancement to further minimize the donor-site morbidity, resulting in excellent functional and aesthetic outcomes. © 2007 Wiley-Liss, Inc. Microsurgery, 2007. [source]

Anterior versus posterior approach in reconstruction of infected nonunion of the tibia using the vascularized fibular graft: potentialities and limitations

MICROSURGERY, Issue 3 2002
Sherif M. Amr M.D.
The potentialities, limitations, and technical pitfalls of the vascularized fibular grafting in infected nonunions of the tibia are outlined on the basis of 14 patients approached anteriorly or posteriorly. An infected nonunion of the tibia together with a large exposed area over the shin of the tibia is better approached anteriorly. The anastomosis is placed in an end-to-end or end-to-side fashion onto the anterior tibial vessels. To locate the site of the nonunion, the tibialis anterior muscle should be retracted laterally and the proximal and distal ends of the site of the nonunion debrided up to healthy bleeding bone. All the scarred skin over the anterior tibia should be excised, because it becomes devitalized as a result of the exposure. To cover the exposed area, the fibula has to be harvested with a large skin paddle, incorporating the first septocutaneous branch originating from the peroneal vessels before they gain the upper end of the flexor hallucis longus muscle. A disadvantage of harvesting the free fibula together with a skin paddle is that its pedicle is short. The skin paddle lies at the antimesenteric border of the graft, the site of incising and stripping the periosteum. In addition, it has to be sutured to the skin at the recipient site, so the soft tissues (together with the peroneal vessels), cannot be stripped off the graft to prolong its pedicle. Vein grafts should be resorted to, if the pedicle does not reach a healthy segment of the anterior tibial vessels. Defects with limited exposed areas of skin, especially in questionable patency of the vessels of the leg, require primarily a fibula with a long pedicle that could easily reach the popliteal vessels and are thus better approached posteriorly. In this approach, the site of the nonunion is exposed medial to the flexor digitorum muscle and the proximal and distal ends of the site of the nonunion debrided up to healthy bleeding bone. No attempt should be made to strip the scarred skin off the anterior aspect of the bone lest it should become devitalized. Any exposed bone on the anterior aspect should be left to granulate alone. This occurs readily when stability has been regained at the fracture site after transfer of the free fibula. The popliteal and posterior tibial vessels are exposed, and the microvascular anastomosis placed in an end-to-side fashion onto either of them, depending on the length of the pedicle and the condition of the vessels themselves. To obtain the maximal length of the pedicle of the graft, the proximal osteotomy is placed at the neck of the fibula after decompressing the peroneal nerve. The distal osteotomy is placed as distally as possible. After detaching the fibula from the donor site, the proximal part of the graft is stripped subperiosteally, osteotomized, and discarded. Thus, a relatively long pedicle could be obtained. To facilitate subperiosteal stripping, the free fibula is harvested without a skin paddle. In this way, the use of a vein graft could be avoided. Patients presenting with infected nonunions of the tibia with extensive scarring of the lower extremity, excessively large areas of skin loss, and with questionable patency of the anterior and posterior tibial vessels are not suitable candidates for the free vascularized fibular graft. Although a vein graft could be used between the recipient popliteal and the donor peroneal vessels, its use decreases flow to the graft considerably. These patients are better candidates for the Ilizarov bone transport method with or without free latissimus dorsi transfer. © 2002 Wiley-Liss, Inc. MICROSURGERY 22:91,107 2002 [source]

Histologic Analysis of Clinical Biopsies Taken 6 Months and 3 Years after Maxillary Sinus Floor Augmentation with 80% Bovine Hydroxyapatite and 20% Autogenous Bone Mixed with Fibrin Glue

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2001
Mats Hallman DDS
Abstract: Background: Bovine hydroxyapatite (Bio-Oss®, Geistlich Pharmaceutical, Wollhausen, Switzerland) has been suggested to be used in maxillary sinus floor augmentation procedures prior to or in conjunction with implant placement. However, the long-term histologic fate of this material is not well understood. Purpose: The aim with this study was to histologically evaluate the tissue response in patients to a mixture of bovine hydroxyapatite (BH), autogenous bone, and fibrin glue 6 months and 3 years after a maxillary sinus floor augmentation procedure. Materials and Method: Biopsies were taken from a group of 20 consecutive patients 6 months (n = 16) and 3 years (n = 12) after maxillary sinus floor augmentation with a mixture of BH (80%), autogenous bone (20%), and fibrin glue and prepared for histologic analysis. Results: Light microscopy and morphometry from biopsies taken after 6 months showed various amounts of mineralized bone tissue. The specimen area was occupied by 54.1 ± 12.6% nonmineralized tissue, followed by 21.2 ± 24.5% lamellar bone, 14.5 ± 10.3% BH particles, and 10.2 ± 13.4% woven bone. The nonmineralized tissue seen in bone-forming areas consisted of a loose connective tissue, rich with vessels and cells. There were no signs of resorption of the BH particles. The lamellar bone appeared to have originated from the recipient site and was seldom in contact with the BH particles. After 3 years, the nonmineralized tissue area had decreased to 36.0 ± 19.0% (p > .05) and consisted mainly of bone marrow tissue. The surface area of lamellar bone had increased to 50.7 ± 22.8% (p > .05), and there was almost no immature bone. The mean specimen area occupied by BH particles, was 12.4 ± 8.7% and had not changed from 6 months (not significant). Moreover, the sizes of the particles were similar after 6 months and 3 years. The degree of BH particle,bone contact had increased from 28.8%± 19.9% after 6 months to 54.5 ± 28.8% after 3 years (p > .05). Conclusion: Histology of specimens from maxillary sinuses augmented with 80% BH particles, 20% autogenous bone, and fibrin glue showed a positive bone tissue response after 6 months and 3 years after augmentation of the maxillary sinus floor prior to implant placement in a group fo 20 patients. The bone surrounding and in contact with the BH particles after 6 months was mainly immature woven bone, which with time was replaced by mature lamellar bone filling the interparticle space as observed in the 3-year specimens. Moreover, bone-integrated BH particles seem to be resistant to resorption. The results indicate that the procedure may be considered when only small amounts of intraoral autogenous bone graft are available. [source]

Bone tissue responses to glass fiber-reinforced composite implants , a histomorphometric study

CLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2009
A. M. Ballo
Abstract Objectives: The aims of this study were to evaluate bone-to-implant contact (BIC) and the osteoconductive capacity of bioactive fiber-reinforced composite implant (FRC) in vivo. Material and methods: Threaded sand-blasted FRC implants and threaded FRC implants with bioactive glass (BAG) were fabricated for the study. Titanium implants were used as a reference. Eighteen implants (diameter 4.1 mm, length 10 mm) were implanted in the tibia of six pigs using the press-fit technique. The animals were sacrificed after 4 and 12 weeks. Histomorphometric and scanning electron microscopic (SEM) analyses were performed to characterize BIC. Results: In general, the highest values of BIC were measured in FRC-BAG implants, followed by FRC and Ti implants. At 4 weeks, the BIC was 33% for threaded FRC-BAG, 27% for FRC and 19% for Ti. At 12 weeks, BIC was 47% for threaded FRC-BAG, 40% for FRC and 42% for Ti. Four weeks after implantation, all the implants appeared biologically fixed by a newly formed woven bone arranged in the thin bone trabeculae filling the gap between the implant and the bone of the recipient site. Twelve weeks after implantation, the thickness of the woven bone trabeculae had increased, especially around the FRC-BAG implants. Conclusion: Our results suggest that the FRC implant is biocompatible in bone. The biological behavior of FRC was comparable to that of Ti after 4 and 12 weeks of implantation. Furthermore, the addition of BAG to the FRC implant increased peri-implant osteogenesis and bone maturation. [source]

Horizontal ridge augmentation using autogenous block grafts and the guided bone regeneration technique with collagen membranes: a clinical study with 42 patients

CLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2006
Thomas Von Arx
Abstract Objective: To analyze the clinical outcome of horizontal ridge augmentation using autogenous block grafts covered with anorganic bovine bone mineral (ABBM) and a bioabsorbable collagen membrane. Material and methods: In 42 patients with severe horizontal bone atrophy, a staged approach was chosen for implant placement following horizontal ridge augmentation. A block graft was harvested from the symphysis or retromolar area, and secured to the recipient site with fixation screws. The width of the ridge was measured before and after horizontal ridge augmentation. The block graft was subsequently covered with ABBM and a collagen membrane. Following a tension-free primary wound closure and a mean healing period of 5.8 months, the sites were re-entered, and the crest width was re-assessed prior to implant placement. Results: Fifty-eight sites were augmented, including 41 sites located in the anterior maxilla. The mean initial crest width measured 3.06 mm. At re-entry, the mean width of the ridge was 7.66 mm, with a calculated mean gain of horizontal bone thickness of 4.6 mm (range 2,7 mm). Only minor surface resorption of 0.36 mm was observed from augmentation to re-entry. Conclusions: The presented technique of ridge augmentation using autogenous block grafts with ABBM filler and collagen membrane coverage demonstrated successful horizontal ridge augmentation with high predictability. The surgical method has been further simplified by using a resorbable membrane. The hydrophilic membrane was easy to apply, and did not cause wound infection in the rare instance of membrane exposure. [source]

In Vivo Follicular Unit Multiplication: Is It Possible to Harvest an Unlimited Donor Supply?

Recipient Area Hair Direction and Angle in Hair Transplanting

DERMATOLOGIC SURGERY, Issue 6 2004
Walter P. Unger MD
Background. A variety of recommendations for creating "natural" hair directions and angles in hair transplanting have been described. Objective. A method of accomplishing that goal is outlined. Methods. Hair direction and angle are determined by multiple partings of the hair during the course of making recipient sites. Incisions are made to mimic such directions and angles. The direction is usually somewhat coronal and the use of grafts containing more than one follicular unit is particularly advantageous in producing a denser appearance. Results. If the above technique is employed, one does not accelerate the rate at which existing hair in the recipient area is lost and the hair flows in a natural easy to manage fashion. Conclusion. Surgeons should nearly always mimic the scalp hair directions and angles seen in nature. [source]

Pulsed erbium:YAG laser-assisted autologous epidermal punch grafting in vitiligo

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2000
Mukta Sachdev MD
Background A pilot study was conducted to evaluate the efficacy and safety of pulsed erbium:YAG laser ablation of autologous minipunch grafted sites for the treatment of refractory or stable vitiligo. Methods Thirteen patients, seven men and six women, aged between 19 and 58 years, with Fitzpatrick skin types ranging from type IV to VI, were grafted. The pulsed erbium: YAG laser was used to create recipient graft sites. Results Repigmentation was observed in 12 out of 13 patients. Failure of grafts to repigment ranged from 3% to 100%. No untoward side-effects of surgery were noted. Conclusions Using an erbium:YAG laser to create graft recipient sites permits the survival of punch harvested grafts and the spread of pigmentation to the surrounding skin. [source]

Could translocation aid hen harrier conservation in the UK?

ANIMAL CONSERVATION, Issue 1 2001
Mark Watson
Translocation is increasingly used in conservation to re-establish or augment populations of threatened species or to remove individual animals from areas of human-wildlife conflict. We assess the feasibility and utility of translocating hen harriers (Circus cyaneus) in the UK to enhance their distribution and abundance whilst simultaneously reducing the impact of harrier predation on red grouse (Lagopus lagopus scoticus) populations and shooting bags. Current knowledge of hen harrier feeding ecology, dispersal, survival and recruitment suggests that they would be suitable subjects for translocation with the aim of increasing their distribution in the UK. Assessment of habitat and food availability suggest that there are suitable recipient sites beyond the current range of the hen harrier in the UK. However, translocation would not be a sustainable method of reducing predation on grouse moors because it would have to continue indefinitely as long as grouse moors attracted harriers. Translocation of harriers to grouse moors where they have been locally extirpated would not be appropriate until levels of illegal control are reduced. Establishing new harrier populations through translocation away from grouse moors may become desirable if initiatives to reduce human-raptor conflicts on grouse moors are unsuccessful, or as an interim measure to accelerate the recovery of hen harriers in the UK. [source]

Quantitation of Mandibular Symphysis Volume as a Source of Bone Grafting

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 2 2010
Fernando Verdugo DDS
ABSTRACT Background: Autogenous intramembranous bone graft present several advantages such as minimal resorption and high concentration of bone morphogenetic proteins. A method for measuring the amount of bone that can be harvested from the symphysis area has not been reported in real patients. Purpose: The aim of the present study was to intrasurgically quantitate the volume of the symphysis bone graft that can be safely harvested in live patients and compare it with AutoCAD® (version 16.0, Autodesk, Inc., San Rafael, CA, USA) tomographic calculations. Materials and Methods: AutoCAD software program quantitated symphysis bone graft in 40 patients using computerized tomographies. Direct intrasurgical measurements were recorded thereafter and compared with AutoCAD data. The bone volume was measured at the recipient sites of a subgroup of 10 patients, 6 months post sinus augmentation. Results: The volume of bone graft measured by AutoCAD averaged 1.4 mL (SD 0.6 mL, range: 0.5,2.7 mL). The volume of bone graft measured intrasurgically averaged 2.3 mL (SD 0.4 mL, range 1.7,2.8 mL). The statistical difference between the two measurement methods was significant. The bone volume measured at the recipient sites 6 months post sinus augmentation averaged 1.9 mL (SD 0.3 mL, range 1.3,2.6 mL) with a mean loss of 0.4 mL. Conclusion: AutoCAD did not overestimate the volume of bone that can be safely harvested from the mandibular symphysis. The use of the design software program may improve surgical treatment planning prior to sinus augmentation. [source]