Feature Papers in Biomedical Materials

Aim: Triclosan is an antiseptic substance that has been shown in preclinical studies to reduce bacterial load in the wound and slow bacterial growth by inhibiting fatty acid synthesis. It is claimed that the coating protects against colonization of the tissue around the suture. This study aimed to compare the safety and efficacy of triclosan-coated polydioxanone versus uncoated polydioxanone sutures for the prevention of surgical site infections (SSIs) following hypospadias repair in children. Methods: The medical records of 550 children who underwent hypospadias repair between 1 January 2014 and 31 December 2023 were retrospectively analyzed. The patients included in the study were divided into two groups. The first group consisted of the patients in whom polydioxanone (PDS II) was used (n = 262), while in the patients of the second group (n = 288), triclosan-coated polydioxanone (PDS Plus) was used for hypospadias repair. Secondary outcomes were defined as the occurrence of early and late complications, the number of readmissions within 30 days after surgery (ReAd), unplanned return to the operating room (uROR), and repeat operations. Results: The median age of all children enrolled in the study was 16 (IQR 14, 20) months. The patients in whom PDS Plus was used for hypospadias repair had a significantly lower number of SSIs than the patients in whom PDS II was used (n = 18 (6.9%) vs. n = 4 (1.4%), p < 0.001). Wound infection led to wound dehiscence in 10 of 18 patients from the PDS II group, while all four wound infections from the PDS Plus group led to wound dehiscence (p = 0.07). The number of postoperative urethrocutaneous fistulas was significantly lower in the patients in whom PDS Plus was used (13.7% vs. 8.3%, p = 0.042). The incidence of late complications did not differ between the study groups: meatal stenosis (p = 0.944), residual chordee (p = 0.107), urethral stricture (p = 0.196), scarring (p = 0.351) and urinary discomfort (p = 0.713). There were no cases of uROR in either group. The ReAd rate was low in both groups (n = 5 (1.9%) vs. n = 2 (0.6%), p = 0.266). The frequency of reoperations was lower in the group of patients treated with PDS Plus than in the group of patients treated with PDS II (11.1% vs. 20.6%; p = 0.03). Conclusion: The use of PDS Plus in hypospadias surgery significantly reduces the incidence of SSI, postoperative fistulas, and reoperation rates compared to PDS II. Full article

Background: This study evaluated the effectiveness, safety, and possible changes in bowel symptoms after multicompartment prolapse surgery by comparing two different surgical approaches, transvaginal mesh surgery with levatorplasty (TVMLP) and robot-assisted sacrocolpopexy (RSC). Methods: All patients underwent pelvic (POP-Q staging system) and rectal examination to evaluate anal sphincter tone in the lithotomy position with the appropriate Valsalva test. The preoperative evaluation included urodynamics and pelvic magnetic resonance defecography. Patient Global Impression of Improvement (PGI-I) at follow-up measured subjective improvement. All patients completed Agachan–Wexner’s questionnaire at 0 and 12 months of follow-up to evaluate bowel symptoms. Results: A total of 73 cases were randomized into the RSC group (36 cases) and TVMLP group (37 cases). After surgery, the main POP-Q stage in both groups was stage I (RCS 80.5% vs. TVMLP 82%). There was a significant difference (p < 0.05) in postoperative anal sphincter tone: 35%. The TVMLP group experienced a hypertonic anal sphincter, while none of the RSC group did. Regarding subjective improvement, the median PGI-I was 1 in both groups. At 12 months of follow-up, both groups exhibited a significant improvement in bowel symptoms. Conclusions: RSC and TVMLP successfully corrected multicompartment POP. RSC showed a greater improvement in the total Agachan–Wexner score and lower bowel symptoms. Full article

Whole-organ plastic resin casting is a very useful method for preserving rare pathological specimens for forensic/anatomical studies and for teaching/research purposes. Many techniques have been proposed over time, but most of them use special non-commercially available resin mixtures, lengthy protocols, and are overall not easily implemented in any anatomy/pathology department that might need such a procedure for rapid organ preservation. Here, we utilized anatomical sections of the human brain, heart, kidneys, spleen, large intestine, and lungs from on-display organs that were fixed for more than 1 year in 10% neutral-buffered formalin and from a freshly processed cadaver for teaching purposes in our Human Anatomy Department, and we optimized a fast-processing protocol without the use of any clearing agents, which yields solid, clear, cylindrical resin casting blocks. The resulting protocol, which takes no longer than 4 days, proves that at least three commonly used epoxy resins from hobby shops can be utilized without any restrictions, and the use of resin or glycerin vacuum-forced impregnation even offers two choices of intrinsic contrast, depending on the nature of the preparation. A number of innovations have been included here and compared to existing publications, such as the use of a system of permanent fixation plexiglas rods that maintain the organ in the desired position and become invisible in the final block, the use of UVC sterilization of the tissue to ensure a long shelf life of the block, and the utilization of cheap cylindrical polypropylene food containers as casting molds. Altogether, we present a simple resin-embedding protocol that can be made available to any department/institution without the need for expensive materials and specially trained personnel. Full article

The aim of this study was to assess and compare the marginal bone loss between two different categories of implants (Winsix, Biosafin, Ancona, Italy) having the same diameter and belonging to the Torque Type^® (TT^®) line, in the internal hexagon version (TTi, Group A) and in the external hexagon configuration (TTx, Group B). Patients with one or more straight implants (insertion parallel to the occlusal plane) in the molar and premolar regions in association with tooth extraction at least 4 months prior to implant insertion, who have a fixture diameter of 3.8 mm, who followed up for at least 6 years, and whose radiographic records were available were enrolled in this study. Depending on implant connections (externally or internally), the sample was divided into groups A and B. For externally connected implants (66), the marginal resorption was 1.1 ± 0.17 mm. The subgroup of single and bridge implants showed no statistically significant differences with a marginal bone resorption of 1.07 ± 0.15 mm and 1.1 ± 0.17 mm, respectively. Internally connected implants (69) showed an overall marginal resorption of 0.91 ± 0.17 mm, while the subgroup of single and bridge implants showed resorption of 0.90 ± 0.19 mm and 0.90 ± 0.17 mm, respectively, with no statistically significant differences. According to the obtained results, internally connected implants showed less marginal bone resorption than externally connected implants. Full article

Many hypotheses could explain the mortality decrease observed using hemodiafiltration, such as reduction of intradialytic hypotension and more efficient toxin removal. We led a systematic analysis of representative uremic toxin removal with hemodialysis (HD), online postdilution hemodiafiltration (postHDF) and online predilution hemodiafiltration (preHDF), in a single-center crossover and prospective observational study. The primary outcome was the reduction ratio of uremic toxins of the three categories defined by the Eutox group. Twenty-six patients were treated by those three techniques of extra renal epuration. Mean Kt/Vurea was not different between the treatment methods. Mean reduction ratio of beta2microglobulin was significantly higher for both HDF treatments than for HD (p < 0.001). Myoglobin, kappa, and lambda free light chain reduction ratio was significantly different between the modes: 37.75 ± 11.95%, 45.31 ± 11% and 61.22 ± 10.56%/57.21 ± 12.5%, 63.53 ± 7.93%, and 68.40 ± 11.79%/29.12 ± 8.44%, 34.73 ± 9.01%, and 45.55 ± 12.31% HD, preHDF, and postHDF, respectively (p < 0.001). Mean protein-bound solutes reduction ratio was not different between the different treatments except for PCS with a higher reduction ratio during HDF treatments. Mean albumin loss was always less than 2 g. HDF improved removal of middle molecules but had no effect on indoles concentration without any difference between synthetic dialysis membranes. Full article

Zinc phosphate cement is used in dentistry to lute crowns and bridges. So far, its biocompatibility for other applications has not been studied. This paper reports the biocompatibility of zinc phosphate towards MG63 cells, testing both the material (discs; 3 mm diameter × 1 mm thick) and leachate from the cement. Cell viability was determined using an MTT assay, and cytotoxicity from the effects of leachate, studied in triplicate. Microscopy (optical and scanning electron) determined the morphology and proliferation of cells attached to zinc phosphate. ICP-OES measured element release into leachate, and anti-microbial behaviour was determined against Streptococcus pyrogenes cultured on a Brain Heart Infusion agar using cement discs (3 mm diameter × 1 mm thick). Zones of inhibition were measured after 72 h. MG63 cells proliferated on zinc phosphate surfaces and retained their morphology. The cells were healthy and viable as shown by an MTT assay, both on cement and in leachate. High levels of phosphorus but low levels of zinc were released into leachate. The cement showed minimal antimicrobial activity against S. pyogenes, probably due to the long maturation times used. Zinc phosphate cement was found to be biocompatible towards MG63 cells, which indicates that it may be capable of use in bone contact applications. Full article

(1) Background: The choice of appropriate surgical suture during operation is of great significance. Currently, there are no objective studies regarding the resistance of commonly used sutures in biliary tract surgery. (2) Methods: This fact leads one to conduct research concerning the resistance of the sutures (Polydioxanone, Poliglecaprone, Poliglactin 910, and their analogues coated with antibacterial triclosan) in the environment of sterile and contaminated bile and pancreatic juice. Tensile strength was tested at days 0, 7, 14, 21, and 28 of research. The study was performed in in vitro conditions for 28 days. (3) Results: Pancreatic juice and bile has a significant influence on the tensile strength of each suture. (4) Conclusions: The study indicated that sutures made of polydioxanone had the best qualities during the entire experiment. Full article