In vivo biocompatibility evaluation of 3D-printed nickel-titanium fabricated by selective laser melting.

Nickel-titanium (NiTi) belongs to the group of shape-memory alloys (SMAs), which are characterized by flexibility and reversible deformability. Advanced techniques in 3D printing by selective laser-melting (SLM) process allow the manufacturing of complex patient-specific implants from SMAs. Osteosynthesis materials made of NiTi could be used for minimally invasive surgical approaches in oral- and maxillofacial surgery. However, the in vivo biocompatibility has not yet been fully investigated, especially in load-sharing and load-bearing implants. The aim of this study was to evaluate the in vivo biocompatibility of SLM-produced NiTi for intraosseous and subperiosteal applications. Test specimens were implanted into the frontonasal bone of ten miniature pigs. To assess peri-implant bone metabolism, fluorescent dye was administered after 2, 4, 6, 10, 12, and 14 weeks intraperitoneally. Specimens and the surrounding tissues were harvested after 8 and 16 weeks for histological analysis. While the NiTi implants presented a higher bone-to-implant contact ratio (BIC) after 8 than after 16 weeks (43.3 vs. 40.3%), the titanium implants had a significantly higher BIC after 16 weeks (33.6 vs. 67.7%). Histologically, no signs of peri-implant inflammation or foreign-body reaction were detectable. With respect to this preliminary study design, 3D-printed NiTi shows sufficient biocompatibility for intraosseous and subperiosteal implant placement.

The measurement of wound tensile strength and the effect of PRP on wound tensile force: an experimental investigation on rabbits.

Platelets in PRP are used for their functions in the initiation and regulation of the wound healing process and are used for the repair of injured tissues and the rejuvenation of healthy tissues. In this study, we evaluated the effect of a single dose platelet-rich plasma on skin wound healing and we demonstrated the effect of platelet-rich plasma on skin wound healing by measuring changes in the wound tensile strength.Material and methods: A total of 8 incisions, each 3 cm long, were made on the back skin on both sides of the vertebral column of 12 rabbits. After suturing their backs with staples, platelet rich plasma (PRP) was injected into the edges of the wounds on the left side and saline solution (saline) was injected into the edges of the wounds on the right side. The tensile force that causes wounds to rupture by applying tension was measured on the 7th, 14th, 21st, and 28th days with the help of a special home-designed device.Results: The mean PRP enrichment was 3.19 fold over peripheral blood. The saline to PRP tensile strength ratios on the 7th, 14th, 21st, and 28th days were calculated as 75.7%, 104.0%, 105.3% and 86.5%, respectively. Overall, the difference in the tensile strength for wounds that had received saline or PRP was in-significant.Conclusion: The application of PRP increases the tensile strength of the wound in the early period. It is possible to measure the tensile strength precisely in in vivo studies with economical home-designed devices.

Does the use of Dermojet affect the concentration of platelet-rich plasma? An in vitro experimental investigation.

Needle-free injection systems with high jet pressure have been used for seven decades for drug or vaccine administration via intradermal, subcutaneous, and intramuscular routes. These systems are used for the application of mesotherapy drugs in plastic surgery and dermatology. Platelet-rich plasma (PRP) tissue regeneration is applied intradermally by a needle for different indications, such as wound healing and scar revision. To prevent complaints such as pain, erythema, and ecchymosis by patients during this application, PRP was applied using Dermojet, a jet injector system with a spring-loaded system. In this study, after measuring the average platelet count in PRP preparations obtained from 18 volunteers, a 2.5 cc PRP shot into an empty tube was performed with Dermojet. The mean platelet count was measured in a homogenized tube. The same procedures were performed for platelet-poor plasma (PPP). The platelet loss rates for PRP and PPP were compared. In addition, the amount of PRP in each shot of the Dermojet was calculated. When PRP and PPP were applied using the Dermojet, platelet loss was 8.41% and 8.33%, respectively. The difference in the number of platelets formed in PRP and PPP when applied with Dermojet was not statistically significant. PRP application with needle-free injection systems, such as Dermojet, may be an alternative because of patient comfort and the negligible platelet loss compared with the PRP application with the standard needle injection.

What Is the Adequate PRP Dose for an Effective Treatment? An In Vitro Experimental Study on the Skin.

BACKGROUND: The clinical results of many studies on platelet-rich plasma (PRP) differ due to a lack of standardization in PRP preparation and administration as well as many variables such as PRP preparation methods, platelet concentration, and platelet activation. OBJECTIVES: The authors sought to investigate a different variable that will affect PRP application results. How much PRP should be injected into the unit area of tissue for an effective PRP treatment? METHODS: The study was performed on fresh surplus tissues of 20 patients that were discarded in abdominoplasty and mammoplasty operations. Nine areas of 4 cm2 were marked on the skin. Fluorescein-stained PRP was injected intradermally with 3 different gauge needles at 3 different doses (0.01, 0.03, and 0.05 mL). After injections, spreads of the fluorescent dye-covered areas in horizontal and vertical planes were measured and compared. For the horizontal plane measurements, the dye spread was measured first from the surface of the skin and second from the dermal surface of the skin. In addition, the width and depth of the dye spread in the dermis were measured from vertical sections. RESULTS: Changing the needle diameter does not affect the width or depth (thickness) of the PRP spread in the dermis. Increasing the applied dose to 0.03 mL increases the spread to the width and depth (thickness). CONCLUSIONS: In research evaluating the effectiveness of PRP treatments, it is necessary to report the volume of PRP to be applied per unit of tissue.

Treatment of scalp defects with a combination of trephination and platelet-rich plasma.

In cases of complete scalp loss where the calvarium is exposed and reconstruction cannot be achieved using replantation, or local or far flaps, using trephination to create holes to the depth of the spongeous layer followed by grafting once granulation has covered all defects is an important reconstruction alternative. However, growth of the granulation after trephination and waiting for the entire defect to be covered is a slow process. Since the introduction of platelet-rich plasma (PRP), several researchers have investigated the efficacy of different bone healing and grafting procedures. We present a case with full-thickness partial scalp defect in which we support the development of granulation through holes drilled to the spongeous layer by trephination with PRP.

Platelet-Rich Plasma for Skin Graft Storage: An Experimental Study Using Rabbit Ears.

BACKGROUND: Storage of surplus grafts for later use is one of the standard procedures used in plastic surgery. For the delayed use of skin grafts, various methods and media have been investigated for short-term storage. This study aimed to investigate the effect of platelet-rich plasma (PRP) skin graft storage on the survival of skin grafts obtained from rabbit ears. MATERIALS AND METHODS: Twelve rabbits were used in this study. A total of 12 skin grafts measuring 1 × 1 cm were obtained from the inner surfaces of the rabbits' ears. The grafts were stored at +4°C in saline, Hartmann's, and PRP media. On days 3, 7, 10, and 14, the grafts were implanted into the ears in areas measuring 1 × 1 cm where the skin, cartilage, and perichondria were excised. After the implantation of the grafts, the survival rates were evaluated by measuring the graft areas on day 0, day 10, and day 30. RESULTS: The graft survival rate decreased as the storage period increased in all 3 of the media. The decrease in survival rate was higher in the grafts that were stored in the Hartmann's media in comparison with the saline and PRP media, and the difference was statistically significant. The decrease in graft survival was similar between the storage in saline and PRP media; however, the differences were statistically insignificant. CONCLUSIONS: Although in vitro criteria are important for evaluating graft survival, in vivo studies showing the graft take rate in the recipient area are required. When the in vivo criteria are evaluated, the use of PRP is not superior to the use of saline for graft storage. However, additional studies are required to evaluate the effects of PRP media on graft quality.

Comparison of Two Anticoagulants for Pain Associated with Platelet-Rich Plasma Injections.

BACKGROUND AND AIM: Platelet-rich plasma (PRP) has long been used in skin rejuvenation and hair loss treatment. Some patients require multiple intradermal injections into the face and scalp, and the way in which these patients process and experience pain differs, depending on the patient. Minimizing pain and discomfort during nonsurgical procedures is essential for patient satisfaction. In our experience, the use of acid citrate dextrose-A (ACD-A) as an anticoagulant caused more patient discomfort than did sodium citrate (Na-citrate) among patients who underwent facial rejuvenation with PRP. The aim of the present study was to evaluate patient-related discomfort in PRP sessions using two different anticoagulants. MATERIALS AND METHODS: This clinical trial included 10 patients who received facial PRP injections for facial rejuvenation and 10 patients who received PRP injections in their scalps for hair loss. On the application area, half the surface was treated with Na-citrate PRP injections, and the other half was treated with the same amount of ACD-A PRP injections. Neither the doctors who applied the treatment nor the patients were given information about which anticoagulant was used in each area. Immediately after the procedure, the patients were asked to score their pain on each side of the application area on a scale of 1-10 using a visual analog scale (VAS). RESULTS: PRP injections using Na-citrate as an anticoagulant caused less discomfort on both the face and scalp as compared with that of ACD-A. The outcome was statistically significant. CONCLUSION: Anticoagulants used in PRP preparation affected patients' pain perceptions during the injections. The sensation of pain with PRP prepared with Na-citrate as an anticoagulant was lower than that of PRP prepared with ACD-A. Further studies are required to evaluate the correlation between anticoagulants used for PRP preparation and pain feelings during injections. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Skin graft storage in platelet rich plasma (PRP).

Storage of skin grafts for later use is one of the standard applications in surgery. It is the most preferred method to maintain at +4°C in refrigeration after wrapping the surplus grafts into sterile gauze pad moistened with saline. Although there are many studies on the storage of skin grafts, less is known about storing skin grafts with PRP. Twenty-five pieces of 1 × 1 cm2 partial thickness skin graft were harvested from 12 patients during the reduction mammoplasty operation. Twenty-four grafts were divided into 4 groups, and each group consisted of 6 grafts, 1 graft was analyzed as Day 0. Grafts in Group 1, 2, and 3 were wrapped by sterile gauze pad moistened by either saline (Group 1) or Hartman (Group 2) or PRP (Group 3). Grafts were analyzed macroscopically and microscopically. There were no significant differences between media for the first 10 days. Decrease in viability was less in saline and PRP wrapped grafts at 20 day, viability decreased significantly in all environments after 20 days. Although there was no significant difference in saline or PRP storage, it was observed macroscopically that the grafts stored in the PRP appeared better.

Effects of device variables to radiofrequency (RF) applications.

RF devices have frequency, power and duration setting options, it is important to make sure that the device meets the targeted values at the head output. This study was made to evaluate the RF device output value accuracy and the effects of different frequencies on the tissue heat levels. RF was applied to invitro tissues obtained from surgical operations, and invivo tissues during operations. Heat differences and depth were measured by laser/IR thermometer and thermal infrared camera. First, the output frequency and power values provided by the device were approved. Then, three three heads (monopolar, bipolar and tripolar) with three different frequencies (1,7, 20 MHz) were used. Depth of heat increase was evaluated in millimeters. The results showed that temperature increase varied between 10°C and 30°C at different depths using different frequencies. Heating of the skin with a radiofrequency device in a therapeutic dose is possible if the appropriate frequency and adequate power values are applied. Because the therapeutic temperature is close to the complication limit, the practitioner should be an expert using the device, well-knowledgeable about the regional skin structure and thickness, as well as be able to properly adjust the application doses in order to get therapeutic results.

Effects of omentin on flap viability: an experimental research on rats.

Background: Viability decreases at the distal parts with an increase in the length of flaps. In this study, we evaluated the effects of subcutaneously administered omentin on flap viability, where it is applied to distal one-third part of McFarlane flaps elevated from the rat's dorsal skin.Materials and methods: Twenty-four adult, female, Sprague-Dawley rats were used. Subjects were divided into three groups; group 1 is the control group, group 2 received omentin 1 week before flap elevation, and group 3 received omentin 2 d before and at the day of flap elevation. About 1 cc (300 nanogram/cc) omentin applied by subcutaneous injections to the distal one-third flap. Photos are taken daily for macroscopic evaluations. The 3-mm full thickness punch biopsies at the third day and 1-cm2 biopsies at the seventh day from the middle of the one-third distal third of the flaps were taken. Necrotic and viable areas were measured. Neutrophil counting, epidermis thickness, inflammation, edema, and vascular endothelial growth factor (VEGF) immune staining were evaluated using histopathological analyses. Endothelial Nitric Oxide Synthase (eNOS) expression was performed by ELISA.Results: Omentin increased the percentage of the viable areas of flaps, epidermal thickness, number of newly formed blood vessels, and eNOS expression levels. The results showed statistical significance.Conclusions: Omentin human increases the viable areas of flaps and may be used for enhancement of flap survival.

The repair of complex penile defect with composite anterolateral thigh and vascularized fascia lata flap.

One-stage reconstruction of complex penile defects with functional and cosmetic results is a challenging procedure. The selection of proper technique and materials for reconstruction depends on the type of the deficient tissue components, the size of the wound surface, and the donor site. This article presented a case of a partial penile and urethral defect due to an infection in the previous surgical site. The patient was treated with a perforator based pedicled composite anterolateral thigh flap combined with vascularized fascia lata. The urethral defect was reconstructed with the vascularized fascia lata. The remaining part of the flap was used for the resurfacing of the right cavernous body and penile skin defect. There was no fistula and the urinary caliber was accepted as good. The pedicled composite anterolateral thigh flap contains various tissue components suitable for a functional and cosmetic reconstruction of complex penile defects using the one-stage technique.

Awful face of the war-impacted smoke bomb capsule in the face and systemic toxicity: reports from the conflict in Syria.

In this study, a rare kind of injury due to smoke bomb capsule impaction to midface and under the cranial base is presented, and maneuvers to reduce mortality are discussed. Three male patients were presented with impacted smoke bomb capsules into the midface and under the cranial base structures. Midface structures, anterior cranial base, and, in 2 patients, unilateral eye were severely damaged. Two patients died after the initial emergency operations because their lung disease progressed to acute respiratory distress syndrome. One of the patients lived, and soft tissue reconstruction was achieved by using temporal transposition and cheek advancement skin flaps with split-thickness skin graft from donor site. However, craniofacial destruction is important in these patients; a multidisciplinary approach is needed for the treatment of direct smoke bomb injuries because the patients experienced chemical burn and acute trauma. The timing of maxillofacial reconstruction is also a question in these specific patients.

Does reduction mammaplasty revert skeletal disturbances in the vertebral column of patients with macromastia? A preliminary study.

BACKGROUND: Enlarged breasts are associated with many physical and psychological symptoms. It is important to use objective criteria in documenting physical changes of a patient's body due to enlarged breasts and the benefits of surgery. This preliminary study aimed to determine whether the reduction mammaplasty procedure changes the angles of cervical lordosis, thoracic kyphosis, and lumbar lordosis. METHODS: The study population consisted of 22 patients who underwent breast reduction surgery. All the patients had lateral cervicothoracolumbar radiographs taken preoperatively and at least 2 months postoperatively. Cervical lordosis, thoracic kyphosis, and lumbar lordosis angles, as well as sagittal balance, were examined. The body mass index (BMI), breast tissue volume, and excised tissue amount of each patient were recorded. RESULTS: All the patients had increased cervical lordosis and thoracic kyphosis angles preoperatively, and the angles were significantly decreased postoperatively. Of the 22 patients, 7 had decreased and 8 had increased lumbar lordosis angles. All the lordosis angles showed significant improvement at the last examination. Seven patients had disturbed sagittal balance preoperatively, and all had normal sagittal balance postoperatively. Preoperative total breast tissue volume was positively correlated with the differences in cervical lordosis angles, BMI, preoperative cervical lordosis angles, and cervical lordosis angles. CONCLUSION: Hypertrophic breasts are not only a cosmetic but also a functional problem complicated by pathologic conditions in the vertebral column such as increased cervical lordosis, thoracic kyphosis, and increased or decreased lumbar lordosis. Breast reduction may improve these pathologic angles. Reducing the nonphysiologic weight of enlarged breasts located anterior to the main axis of the body may correct pathologic angulation and disturbed sagittal balance of the vertebral column. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .