The effect of resin cement shade and restorative material type and thickness on the final color of resin-matrix ceramics.

PURPOSE: This study aims to evaluate the effects of cement shade, restorative material type, and thickness on the final color of resin-matrix ceramics. METHODS: Ninety A2 shade resin-matrix ceramic specimens were prepared from Vita Enamic, GC Cerasmart, and Lava Ultimate at 0.5 and 1.0 mm thicknesses. Sixty resin cement disks were fabricated from different shades (A1, A3O, B05, and TR) of RelyX Ultimate at 0.1 mm thickness. CIE color coordinates were measured using a spectrophotometer, and color differences (∆E00) were calculated. Data were statistically analyzed (P =0.05). RESULTS: The ΔE00 values were influenced by the cement shade, restorative material type, thickness, and their interactions (P < 0.05). A3O cement caused clinically unacceptable values for all groups at 0.5 mm thickness and GC at 1.0 mm thickness. A1 and TR cement shades demonstrated visually perceptible but clinically acceptable values, except for VE-A1 and LU-A1 at 0.5 mm thickness. The ∆E00 values of the B05 cement shade were lower than the visually perceptible threshold for both thicknesses except for GC at 0.5 mm thickness. CONCLUSION: The shade of the resin cement and the type and thickness of the resin-matrix ceramic material significantly affected the resulting final color. To provide a shade matching with natural dentition and to obtain esthetic restorations, especially for the anterior teeth, the resin cement shade and resin-matrix ceramic material should be carefully selected.

Predictive and Prognostic Role of Lipocalin-2 Expression in Prostate Cancer and Its Association with Gleason Score.

Lipocalin-2 has an important role in tumor progression, invasion, and metastasis. However, its role in prostate cancer remains unclear. The objective of this study is to determine the expression level of lipocalin-2 in human prostate cancer tissues and to evaluate the relationship between its expression level and clinicopathologic parameters including response to docetaxel treatment, Gleason score, progression-free survival (PFS), and overall survival (OS). We retrospectively analyzed paraffin-embedded tissue sections from 33 metastatic castrate-resistant prostate cancer (mCRPC) patients whose clinical outcomes had been tracked after docetaxel treatment. The expression status of lipocalin-2 was defined by immunohistochemistry (IHC) using the anti-lipocalin-2 antibody. Lipocalin-2 was highly expressed in 36% of the examined specimens. There was no significant correlation between high lipocalin-2 expression and docetaxel response (p : 0.09). High lipocalin-2 expression was significantly associated with a higher Gleason score (p=0.027). Kaplan-Meier survival analysis failed to show a significant correlation between expression levels of lipocalin-2 and both OS and PFS although patients with high lipocalin-2 levels had a numerically shorter PFS and OS time compared to patients with low levels. Consequently, it is clear that further studies are needed to evaluate the predictive and prognostic role of lipocalin-2 in prostate cancer patients.

Optical properties of contemporary monolithic CAD-CAM restorative materials at different thicknesses.

OBJECTIVE: This study evaluated the optical properties of contemporary monolithic CAD-CAM materials with different chemical compositions. MATERIALS AND METHODS: Totally, 210 rectangular-shaped, A2 shade specimens (12 × 14 mm) were fabricated from VITA Suprinity T, VITA Enamic T, VITA Mark II, GC Cerasmart LT, Lava Ultimate LT, IPS e.max CAD LT and Prettau Anterior blocks and polished to thicknesses of 0.5 ± 0.01 and 1.0 ± 0.01 mm (n = 15 each material). A dental spectrophotometer (VITA Easyshade Compact) was used to calculate the translucency parameter (TP) and opalescence parameter (OP) values of all tested materials. Statistical analysis was performed using one-way analysis of variance, multiple comparison Tukey's test and independent samples t-test (P = .05). RESULTS: In the 0.5-mm thickness group, GC Cerasmart and Prettau Anterior had the highest and lowest translucency values, respectively. VITA Suprinity had the highest OP value, whereas VITA Mark II and Prettau Anterior had the lowest OP values. In the 1.0-mm thickness group, GC Cerasmart and Lava Ultimate had the highest translucency, whereas Prettau Anterior had the lowest translucency. VITA Suprinity and Prettau Anterior had the highest and lowest OP values, respectively. CONCLUSIONS: The optical properties of monolithic restorative materials were influenced by the type and thickness of the material used. CLINICAL SIGNIFICANCE: According to the results of this study, monolithic materials with different chemical compositions have revealed different optical properties. To obtain esthetic restorations and provide shade matching with natural dentition especially for anterior teeth, monolithic materials should be carefully chosen.

Clinicopathological evaluation of Marjolin ulcers over two decades.

Malignant changes arising on the previously traumatized or chronically inflamed skin are defined as Marjolin ulcers. They can develop on many different lesions but frequently they are detected on burn scars. Histopathologically, Marjolin ulcers are mostly diagnosed as squamous cell carcinoma and they need special attention when especially located on the lower extremities. In this study, 63 patients treated for Marjolin ulcers between January 2000 and March 2015 were evaluated according to etiology, histological differentiation, primary tumor size, patient age and anatomical localization. Medical records of these patients were reviewed retrospectively. Mean age was 49.7 years. Average interval between the first injury and carcinoma development was 37.9 years. Most frequent etiologic factor was burn scars with 82.5%. Foot was the most frequently affected site with 28.6% and scalp was the second most frequent localization with 25.4%. Squamous cell carcinomas were detected in 88.9% of the patients and basal cell carcinomas were detected in 11.1% of the patients. For treatment, excision and grafting was performed for 48 patients (76.2%), excision and local flaps were used for 10 patients (15.9%) and excision and free flaps were used for five patients (7.9%). Regional lymph node dissection was performed for 12 patients (19%). Average follow up period was 46.5 months. Local recurrences were detected in nine patients (14.3%). In conclusion, Marjolin ulcers are aggressive tumors that require special care. In order to prevent life threatening sequelas of this entity, it is important to know basic aspects of clinical progress, prognostic factors and treatment modalities.

The Effect of Pseudoexfoliation Syndrome on the Retinal Nerve Fiber Layer and Choroid Thickness.

PURPOSE: To investigate thickness of the retinal nerve fiber layer (RNFL) and choroid thickness in patients with pseudoexfoliation syndrome (PEX) and pseudoexfoliation glaucoma (PXG) compared to healthy volunteers. METHODS: This cross-sectional, prospective study included 43 patients with PXG, 45 patients with PEX syndrome, and 48 healthy volunteers. The RNFL and macular thickness were analyzed with standard OCT protocol while choroidal thickness was analyzed with EDI protocol in all subjects. RESULTS: The RNFL thickness was higher in the PEX and control groups compared to the PXG group (p<0.001). The choroid thickness was significantly higher in the control group compared to the PXG and PEX groups (p<0.05). No significant difference was detected between the both groups. CONCLUSIONS: PEX might weaken choroid circulation by accumulating in choroid vessels. The thinner choroid in the PXG group suggests that ischemia affects the duration of PEX and has a role in the development of glaucoma.

Age and gender related changes in bronchial tree: a morphometric study with multidedector CT.

OBJECTIVE: The aims of this study are the identification of differences in the diameter, length, area and branching angles of the trachea and bronchi with gender and age, and the identification of trachea types by using MDCT images. PATIENTS AND METHODS: The thoracic MDCT images of 253 patients (0-74 years old, 142 male and 111 female) were evaluated. Tracheal diameter, tracheal cross-sectional area, diameter and length of bronchi, and several angles of the bronchial tree [e.g. subcarinal angles (SCA), interbronchial angles (IBA)] were measured. RESULTS: Average anteroposterior and transverse diameter of the trachea in adult patients were measured as 15.8 ± 2.9 mm and 17.5 ± 3.7 mm respectively. Average tracheal cross-sectional areas in adult patients were calculated as 160.7 ± 41.3 mm² in females and as 275.7 ± 57.3 mm² in males. Four types of trachea were identified as circular (68% in adults, 73% in children), oval (13%, 15%), rectangular (11%, 5%) and horseshoe shaped (8%, 7%). The average right and left SCA were calculated as 34.5º ± 8.1º and 38.1º ± 8.9º respectively. The average right and left IBA were calculated as 32.4º ± 7.7º and 35.2º ± 8.1º respectively. CONCLUSIONS: The findings of this study may be helpful during bronchoscopy and tube and stent application procedures. MDCT seems to be a convenient technique for the evaluation of the bronchial tree.

Evaluation of marginal/internal fit of chrome-cobalt crowns: Direct laser metal sintering versus computer-aided design and computer-aided manufacturing.

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the internal and marginal fit of chrome cobalt (Co-Cr) crowns were fabricated with laser sintering, computer-aided design (CAD) and computer-aided manufacturing, and conventional methods. MATERIALS AND METHODS: Polyamide master and working models were designed and fabricated. The models were initially designed with a software application for three-dimensional (3D) CAD (Maya, Autodesk Inc.). All models were fabricated models were produced by a 3D printer (EOSINT P380 SLS, EOS). 128 1-unit Co-Cr fixed dental prostheses were fabricated with four different techniques: Conventional lost wax method, milled wax with lost-wax method (MWLW), direct laser metal sintering (DLMS), and milled Co-Cr (MCo-Cr). The cement film thickness of the marginal and internal gaps was measured by an observer using a stereomicroscope after taking digital photos in ×24. RESULTS: Best fit rates according to mean and standard deviations of all measurements was in DLMS both in premolar (65.84) and molar (58.38) models in µm. A significant difference was found DLMS and the rest of fabrication techniques (P < 0.05). No significant difference was found between MCo-CR and MWLW in all fabrication techniques both in premolar and molar models (P > 0.05). CONCLUSION: DMLS was best fitting fabrication techniques for single crown based on the results.The best fit was found in marginal; the larger gap was found in occlusal.All groups were within the clinically acceptable misfit range.

Evaluation of female athlete triad and gynecological complaints in young Turkish female athletes.

PURPOSE: Female athlete triad (FAT) is a serious healthcare concern in the young female population. The aim of this study was to determine the prevalence and clinical characteristics of FAT and its relationship with gynecologic complaints of young Turkish female athletes. MATERIALS AND METHODS: This was a cross-sectional survey and included 87 female athletes involved in a variety of sports as a case group and 85 sedentary female university students from Ege and Celal Bayar Universities. All subjects completed a questionnaire consisting of 32 separate questions assessing eating behavior, menstrual status, gynecologic and systemic complaints, psychological problems, and sexual history. SPSS 21.0 was used for statistical analysis. RESULTS: This survey involved 172 females in between to 30 years of age. The age of menarche was found to be significantly lower in the sedentary group (p = 0.00). Late menstruation and oligoamenorrhea were notable complaints among the athletes, and body mass index (BMI) was found to be statistically lower in the athletic group (p = 0.00). Cold hands and hair loss were seen more often in the sedentary group compared to the athletic group (p < 0.05). According to a logistic regression analysis, independent variables (BMI, menstrual status, and bone fractures) were found to be statistically insignificant (p > 0.05). CONCLUSIONS: Excessive sports activity can be hazardous in young female population. Lower BMI might be related to menstrual irregularity. Young female population should be informed about this relationship, especially athletes who are particularly at risk. Certain precautions should be taken into consideration in this population in order to get benefits of sports activity.

Development and Life Table Parameters of Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae) on Four Ornamental Plants.

The development, reproduction, and life table parameters of the Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae) on four ornamental plant species, namely Pelargonium zonale (Geraniaceae), Hibiscus rosa-sinensis, Hibicus syriacus (Malvaceae), and Cestrum nocturnum (Solanaceae) were investigated under controlled conditions (25 ± 2°C, 60 ± 10% R.H., and 16 h photophase). Life table data were analyzed by using an age-stage two-sex life table. The shortest total immature developmental time of females and males for P. madeirensis was obtained on C. nocturnum (20.42 and 21.90 days, respectively). The highest fecundities were 233 and 232 eggs on C. nocturnum and H. syriacus, respectively. The intrinsic rate of increase (r  = 0.1511 day(-1)) and finite rate of increase (λ  =  1.1631 day(-1)) were the greatest when mealybugs were reared on C. nocturnum. Net reproductive rate (R 0  =  129.5 offspring) was the greatest when reared on H. syriacus, but this value was not statistically different from that on C. nocturnum. The shortest mean generation time (T  =  31.3 days) was calculated on C. nocturnum. These results indicate that C. nocturnum and H. syriacus are more suitable hosts than H. rosa-sinensis and P. zonale for P. madeirensis.

Marginal bone loss of two implant systems with three different superstructure materials: a randomised clinical trial.

Marginal bone level is a criterion for implant success. The aetiological factors of bone loss have not been clarified. The aim of this study was to evaluate the influence of implant systems and prosthetic materials on the marginal bone loss. Twenty-three patients participated; two implant systems and three superstructure materials were used in this study. Twenty-two of the implants were restored with porcelain fused to base metal alloy (BMA), 25 with porcelain fused to noble metal alloy (NMA) and 20 with zirconium oxide-based ceramics. Radiographs were taken at baseline and 3, 6 and 12 months after loading. Crestal bone-level changes were assessed with digital subtraction radiographs. The effects of superstructure materials and implants were evaluated with one-way anova and independent samples t-test, respectively (α = 0·05). The mean crestal bone loss was found 0·483 mm in 3 months, 0·622 mm in 6 months and 0·816 mm in 12 months. Prosthetic materials were found to have greater effect (ß = 0·575, P = 0·015) on crestal bone loss than implant systems (P > 0·05). The porcelain fused to BMA restorations showed higher crestal bone loss than NMA-based restorations (P = 0·003) at 3 months, (P = 0·038), at 6 months and (P = 0·00) at 12 months; however, crestal bone loss differences between NMA and zirconia were not significant (P = 0·629) at 3 months, (P = 0·974) at 6 months and (P = 1) at 12 months. Within the limitations of this study, our results revealed that rather than the implant systems, prosthetic materials seemed to have an effective role on crestal bone.

Ciliary body cysts in neurofibromatosis: a new coexistence?

PURPOSE: Neurofibromatosis 1 (NF1) is an autosomal dominant, multisystem disorder that also effects the eye. Herein, we aimed to investigate the posterior iris surface and ciliary body morphology of NF1 patients by ultrasonic biomicroscopy (UB). MATERIALS & METHODS: Nine consecutive unrelated subjects with NF1, and as a control group 25 healthy subjects, were included in the study. All patients underwent ophthalmic examination including visual acuity testing, slit-lamp biomicroscopy, tonometry, gonioscopy (Schaffer classification), and dilated ophthalmoscopy, UB. RESULTS: Mean age was 35.1 ± 16.2 (range, 11-57) and 34.5 ± 15.6 (range, 9-60) for NF1 and control groups respectively (p>0.05). Lisch nodules were present in 16 of 18 eyes (88.8%) in NF1 group. Fundoscopic examination of the control group and 15 eyes of NF1 (83.3%) patients was normal, whereas hypoplastic and tilted optic nerve were present in three eyes, and temporally-located bone-spicule-like lesions was present in one eye of the NF1 group. UB revealed ciliary body cyst in 77.7% (14/18) of the eyes among NF1 group, and 8% (4/50) among control group (p<0.05). The mean size of the cysts were 520 ± 191 µ (range, 220-860 µ) and 495 ± 231 µ (range, 300-830 µ) at NF1 and control groups, respectively. Gonioscopic evaluation revealed that 55% of the NF1 patients have an unoccludable anterior chamber angle (Grade 3 or 4), 45% occludable angle (Grade 1 or 2), and 78% irregular pigment patches. However, occludable angle rate was just 4% in the control group, and none of the patients had irregular pigment patches. CONCLUSION: The coexistence of ciliary body cysts and NF1, and the effect of these cysts in the eye should be enlightened with further studies.

Molecular typing of Candida albicans strains isolated from denture wearers by repetitive sequence-based PCR.

Long-term use of prosthesis is the most important risk factor for the colonization of Candida species on the mucosal surfaces, which can lead to the development of denture-related stomatitis (DRS). Some individuals wearing prosthesis develop DRS and others do not. C. albicans strains isolated from both groups were genotypically compared. The purpose of this study was to determine whether the strain causing prosthesis stomatitis was different from the other strains genotypically. The study included 90 individuals wearing different prostheses and 20 control individuals with natural teeth. In the study 109 C. albicans strains were used which were isolated from the saliva samples and the mucosal surfaces of the tongues and palates of 51 individuals and then defined phenotypically. Phenotypic diagnosis of the isolates was genotypically verified by using species-specific PCR. For molecular typing, repetitive extragenic palindromic sequence polymerase chain reaction (REP-PCR) was employed. The results of the study revealed that REP-PCR had the capability to separate 109 C. albicans strains and six reference strains into 44 genotypes. Whereas C. albicans strains showed heterogenic distribution, C. albicans strains isolated from the individuals suffering from prosthesis stomatitis showed no specific genotypes. REP-PCR is a simple, fast and low-cost method and helped work on a great number of samples.

Protective effect of grape seed extract against ischaemia/reperfusion injury in a rat epigastricflap model.

Proanthocyanidins are potent natural antioxidants which belong to a class of polyphenols. Proanthocyanidin-rich extracts are prepared from grape seeds. The effect of grape seed proanthocyanidin extract (GSPE) on the viability of abdominal skin flaps exposed to warm ischaemia and subsequent reperfusion were studied in 40 male Wistar rats. In the control group (group I; n=20), rats were fed with standard, non-purified rat diet, and the study group received GSPE 100 mgkg(-1) per day 1 week prior to surgery and 1 week following surgery. Abdominal island flaps were elevated in both the groups and subjected to 8h of warm ischaemia, followed by reperfusion. Mean flap survival areas in groups I (control group) and II (treatment group) were calculated to be 58.3%+/-11.72 and 81.0%+/-11.88, respectively. Flap survival on day 7 was significantly higher in group II compared to group I (p<0.01). Histopathological semi-quantitative analysis of the specimens revealed infiltration by polymorphonuclear leucocytes, oedema formation and necrosis in group I, whereas neo-vascularisation and fibrosis were the prominent findings in group II.

"Lid technique": cyanoacrylate-assisted anastomosis of small-sized vessels.

This paper presents the details of an experimental study of arterial anastomosis, combining suture with the cyanoacrylate tissue adhesive. At the distal end of the vessel, two parallel incisions were made, 180 degrees apart from each other, and two sutures were placed passing from the proximal end to exit from the most distal part of the longitudinal incisions. The tissue adhesive was then applied to the proximal vessel, and the full-thickness vascular 'lid' flap was closed over it on anterior and posterior surfaces. Eighty anastomoses were carried out at the left and the right femoral arteries of 40 Wistar rats. For all of the animals, conventional end-to-end anastomosis was carried out on the left side, and the lid technique was used on the right side. There was no statistically significant difference between the patency rates of the groups (two non-patent in control and two in the study group) (P>0.05), whereas significantly reduced operation time (mean 16.2 and 10.7 min in control and study groups, respectively) (P<0.0001) and bleeding time (median 1.5 and 0.5 min in control and study groups, respectively) (P<0.0001) were documented in the study group. Histopathological evaluation of both the patent and non-patent vessels at day 21 revealed no signs of tissue toxicity or intraluminal adhesive leakage. In view of these data, it was concluded that the technique provides an effective and simple method for end-to-end anastomosis of small-calibre arteries.

Pulley reconstruction with different materials: experimental study.

The digital fibroosseous pulley system is essential for optimum function of the flexor tendons and the continuation of normal hand functions. Different materials have been used for pulley reconstruction in the literature but the ideal material is still controversial. In this study, after the excision of the A2 pulley, pulley reconstructions were performed by using acellular dermal matrix, solvent dehydrated bovine pericardium, fascia lata, and free tendon graft in the rabbit model. The animals were killed at the 8th and 12th weeks and subjected to biomechanical testing. Tendon excursion and work of flexion values were calculated for each digit of the rabbits. As a result, all the reconstructed pulleys were functioning well without a statistically significant difference between the experimental groups. Pulleys reconstructed with acellular dermal matrix and solvent-dehydrated bovine pericardium appear to have the potential to function as effective pulley substitutes.

A comparative study on superior auricular artery island flaps with various pedicles for repair of periorbital defects.

Superior auricular artery (SAA) island flaps elevated from the retroauricular region have perfect color, thickness, and texture match with facial skin. In this article, reconstruction of periorbital defects with SAA island flaps is presented. Flaps were categorized into three types because they were elevated on three different pedicles. A type 1 flap was a superficial temporal vessel pedicled SAA island flap with antegrade blood flow. A type 2 flap was a reverse flow SAA island flap based on the frontal branch of the superficial temporal artery (STA). A type 3 flap was a reverse flow SAA island flap based on the parietal branch of STA. Fourteen patients (9 females and 5 males) aged between 31 years and 74 years were treated with these flaps. Two patients with lower eyelid, two patients with upper eyelid, three patients with malar, two patients with infraorbital, one patient with lateral canthal upper eyelid, and four patients with forehead defects underwent surgical intervention. Sizes of the flaps varied between 3x6 cm and 8x6 cm. Venous congestion was observed in all patients in the early postoperative period and lasted for 5 to 9 (mean, 6.6) days in type 1 flap, 5 to 9 (mean, 6.7) days in type 2 flap, and 2 to 5 (mean, 3.6) days in type 3 flap. Apart from distal necrosis of 1x1 cm in one patient and superficial dermal sloughing in two patients, no complications were encountered. Aesthetically and functionally successful results with minimal donor site morbidity were obtained in all patients during the 2 to 22 (mean 10.8) month follow-up period.

Pull-in suture technique for the treatment of mallet finger.

BACKGROUND: Mallet finger deformity is a common disability that causes discomfort and inconvenience to the patient. Although numerous operative techniques have been described, surgical management remains controversial. METHODS: Between 2002 and 2004, 19 patients with an unsuccessful splinting regimen history, chronic deformities of tendinous origin (>3 months after the injury), or fractures involving 30 percent or more of the articular surface underwent surgical treatment. In 11 patients, chronic mallet finger deformity with tendinous origin was present, whereas eight patients presented with mallet fractures involving more than 30 percent of the articular surface. Open reduction with internal "pull-in" sutures and distal interphalangeal joint immobilization with Kirschner wire was accomplished. Active motions of the proximal interphalangeal and metacarpophalangeal joints were not restricted. After removal of the Kirschner wire at week 6, active flexion exercises were commenced immediately, and daily activities were not restricted. Full activity was allowed at day 7. Goniometric measurements, radiographs, and patient satisfaction were evaluated during the follow-up period. RESULTS: The mean follow-up period of the patients was 16 months (range, 4 to 28 months). Mean extensor lag of the distal interphalangeal joint was 2 degrees (range, 0 to 6 degrees). The mean flexion of the distal interphalangeal joint was 74 degrees (range, 60 to 90 degrees). According to Crawford's evaluation criteria, 14 excellent and five good results were obtained. Apart from radiologically documented mild degenerative changes or joint narrowing in six patients, no complication was encountered. CONCLUSION: The pull-in technique allows accurate realignment of the tendon-bone unit without any specific instrumentation or intraoperative fluoroscopic imaging methods.

Perforating arteries of the gluteal region: anatomic study.

Gluteal artery perforator flaps have gained popularity due to reliability, preservation of the muscle, versatility in flap design without restricting other flap options, and low donor-site morbidity. Today, free or local flaps based on the perforating arteries of the gluteal region are among the most commonly used procedures for the management of lumbosacral defects and autologous breast reconstruction. An anatomic study was carried out to investigate localization, dimension, and distribution of the perforator arteries in 16 gluteal regions of 8 formol-fixed cadavers. The total number of perforators in each gluteal region was 13-20 (mean 17 arteries). Mean vessel diameter and mean vessel length were 1.1 mm (range 0.7-1.7 mm) and 6.4 cm (range, 5.2-9.1), respectively. Topographic analysis of the perforators revealed that the gluteal region can be divided into 3 parts in terms of vessel density. The majority of the perforators were localized in superior zone, whereas the middle zone was documented to be the poorest region. Data derived from this analysis were also confirmed by individual analysis of each cadaver.

Evaluation of osteogenic and chondrogenic activities of prefabricated periallografts.

Reconstruction of cartilage and bone defects has always been a challenging problem for the surgeon. Basic elements that are responsible for the repair process of these tissues are periost and perichondrium. Although several methods for the use of periost and perichondrium are proposed in the literature, the osteogenic and chondrogenic capacities of these tissues were shown to be the most important factor for a successful outcome. Bone and cartilage formation in acellular dermal matrix (ADM) prefabricated with periost and perichondrium was studied in 20 New Zealand rabbits. Morphologic and histologic evaluation and comparison of the newly formed tissues were evaluated. Four rabbits were excluded from the study because of infection, and specimens were obtained at 4, 6, 8, and 12 weeks after the study began from the remaining 16 rabbits. A gradual increase in bone and cartilage tissue formation through the 4th to 12th weeks was documented by reason of perichondrium and periost activation infiltrating into acellular dermal allografts. In view of the data obtained, it was concluded that periost or perichondrium prefabricated over ADM may be an alternative technique of cartilage and bone formation that may provide adequate tissue with elastic and osteo- and chondroconductive properties for the reconstruction of challenging defects.

Improved flap viability with site-specific delivery of sildenafil citrate using fibrin glue.

Sildenafil is a cyclic guanosine-specific phosphodiesterase type 5 (PD-5) inhibitor that is widely used for erectile dysfunction. Potent and competitive inhibition of PD-5 enhances levels of cyclic guanosine monophosphate (cGMP). Fibrin glue-apart from tissue fixation-has been used for slow release of drugs. In this study, local delivery of Sildenafil citrate with fibrin glue was accomplished to improve random flap survival. Fifty Wistar rats were randomized into 5 groups, and a standardized dorsal random-pattern skin flap was elevated in each rat. In Group I (n = 10), the base of the flap was divided, making it a "graft" control to study the graft effect. In Group II (n = 10), a thin Silastic sheet was used to separate the flap from the underlying vascular bed, and no pharmacologic treatment was given. In Group III (n = 10), only 0.5 mL of fibrin glue was applied to the flap donor site. In Group IV (n = 10), 2.5 mg of sildenafil citrate mixed in 0.5 mL of fibrin glue was applied to donor site of the flap, whereas 10 mg of sildenafil citrate mixed in 0.5 mL of fibrin glue was applied in Group V (n = 10). Area of flap survival was evaluated on postoperative seventh day. Total necrosis of all of the flaps was observed in "graft" control group (Group I). Sildenafil and fibrin glue groups (Group IV and V) resulted in a statistically significant decrease in flap necrosis compared with Groups II and III (P < 0.0001). A statistically significant difference could not be documented between Group II and Group III (P > 0.0001). The decrease in skin necrosis was statistically significant in Group V compared with Group IV (P < 0.0001). Histologic examination revealed significantly increased vascular density in Groups IV and V compared with Groups II and III (P < 0.0001), whereas a significant difference could not be documented between Groups IV and V (P > 0.0001) and between Groups II and III (P > 0.0001). In view of these results, topical sildenafil application seems to improve flap survival in random-pattern skin flaps in dose-dependent manner.