BACKGROUND: Effective interventions during the coronavirus disease 2019 (COVID-19) pandemic require an understanding of patients' knowledge and perceptions that influence their behaviour. Our study assessed knowledge of COVID-19 among kidney transplant recipients and donors, hitherto unevaluated. METHODS: We conducted a cross-sectional survey among 325 kidney transplant recipients and 172 donors between 1 May 2020 and 30 June 2020. The survey questionnaire assessed knowledge levels of COVID-19, sociodemographic data, health status, psychosocial impact of COVID-19 and precautionary behaviours during the pandemic. RESULTS: The mean COVID-19 knowledge score of the study population was 7.5 (standard deviation: 2.2) out of 10. The mean score was significantly higher among kidney recipients compared to kidney donors (7.9 [1.9] vs. 6.7 [2.6]; P <0.001). Younger age (21-49 vs. ≥50 years) and higher education (diploma and higher vs. secondary and lower) were associated with significantly higher knowledge scores in donors, but not among recipients ( P -interactions ≤0.01). In both kidney recipients and donors, financial concerns and/or social isolation were associated with lower knowledge levels. CONCLUSIONS Concerted efforts are needed to improve COVID-19 knowledge in kidney transplant recipients and donors, particularly older donors, donors with lower education and patients with financial concerns or feelings of social isolation. Intensive patient education may mitigate the impact of education levels on COVID-19 knowledge levels.
Humans ; COVID-19/epidemiology* ; Kidney Transplantation ; Middle Aged ; Singapore/epidemiology* ; Male ; Female ; Adult ; Cross-Sectional Studies ; Health Knowledge, Attitudes, Practice ; Transplant Recipients/psychology* ; Surveys and Questionnaires ; Tissue Donors/psychology* ; SARS-CoV-2 ; Young Adult ; Aged ; Pandemics

OBJECTIVES: To investigate the clinical application of the digital-assisted reconstruction of the mandible and tumors with free fibula transplantation and immediate implantation via the intraoral approach. METHODS: Twelve patients with benign mandibular tumors were collected. Three-dimensional mandibular reconstruction was performed digitally before surgery to simulate mandibular tumor resection, fibula resection and reconstruction, and implant implantation. The intraoperative resection of the mandibular tumor was conducted through the intraoral approach under the guidance of a guide plate, and fibula resection, molding, reconstruction, and oral fixation were immediately performed. Implant implantation was performed during the second phase of implant surgery and denture restoration was performed 1-2 months after surgery. RESULTS: The types of mandibular defects were BrownⅠ (one case), Ⅰc (four cases), Ⅱ (one case), Ⅱc(three cases), and Ⅲ (three cases). The length of the fibular bone was 12-22 cm. The number of fibular molding amputations was as follows: two cases in two segments, six cases in three segments, three cases in four segments, and one case in five segments. All of these cases underwent folding fibular reconstruction of mandibular and alveolar bone defects. A total of 44 implants were implanted, and none failed after operation. CONCLUSIONS The intraoral approach is a reliable method for the resection of mandibular benign tumors, with few postoperative complications and the ability to position and fix accurately the reconstructed folded fibula under digital design. The immediate implantation of the transplanted fibula does not affect the blood supply and has a high success rate. It is an effective and reliable method for the resection and reconstruction of mandibular benign tumors.
Humans ; Fibula/transplantation* ; Mandibular Neoplasms/surgery* ; Mandibular Reconstruction/methods* ; Bone Transplantation/methods* ; Male ; Middle Aged ; Female ; Mandible/surgery* ; Adult ; Free Tissue Flaps ; Surgery, Computer-Assisted

In recent years, digital bone harvesting and grafting technology in dental implantology has emerged as a cutting-edge advancement in the field of oral medicine, gaining widespread application in the treatment of complex bone defect cases. By integrating digital imaging, virtual design, and precise surgical guidance, this technology has significantly enhanced the success rate of dental implants and improved patient outcomes. However, the rapid development of this technology has also highlighted the lack of standardized clinical protocols, necessitating the establishment of unified guidelines through expert consensus. This article provides a detailed overview of the development process of the group standard Clinical Protocol for Bone Harvesting and Grafting under Digital Guidance in Oral Implantology and offers an in-depth interpretation of its key components, aiming to serve as a valuable reference for clinical practice and academic research.
Humans ; Bone Transplantation/methods* ; Surgery, Computer-Assisted/methods* ; Dental Implantation/methods* ; Tissue and Organ Harvesting/methods* ; Clinical Protocols

PURPOSE: The purpose of this cadaveric study was to compare the volume and weight of bone graft harvested using the curettage vs. the trephination technique from the anterior iliac crest. METHODS: Embalmed cadavers were studied in this experimental research. The right hemipelvis of each cadaver was used for the trephine bone harvesting technique, whereas the left hemipelvis was used for the conventional curettage technique. The weight and the volume of the harvested bone were measured and statistically compared between the 2 sides. The Wilcoxon Signed-Rank test was employed to compare the graft volume and weight obtained from the right and left sides of the hemipelvis. RESULTS: Ten embalmed adult cadavers were used in this study. All subjects were Caucasian males with a mean age of 59.8 years (range 44 - 73 years) at the time of death. A total of 81 cylindrical bone grafts were harvested from the right iliac crest. In 9 out of 81 (11.1%), the cortex of the ilium was penetrated by the chisel. The mean weight of the bone graft harvested with the trephine technique (26.97 ± 2.32) g was heavier than that harvested with the curettage technique (23.74 ± 2.09) g (p = 0.007). Similarly, the volume of the bone graft was higher in the trephine technique (8.40 ± 0.84) cm³ compared to the curettage technique (6.60 ± 1.26) cm³ (p = 0.011). The trephination technique lasted a mean of (12.76 ± 1.87) min (range 10.30-16.10 min), while the curettage technique lasted a mean of (14.53 ± 0.89) min (range 13.50-16.00 min) (p = 0.028). CONCLUSION: Harvesting anterior iliac crest bone graft with the trephine technique provides a higher bone volume and weight than the conventional curettage technique. The trephine technique might be advocated over the curettage technique, especially when a large amount of autologous bone graft is required. However, a meticulous harvesting technique should be followed to prevent complications. In particular, the three-dimensional anatomy should be kept in mind, and the depth of trephination should be well-controlled. CLINICAL TRIAL REGISTRATION Institutional Review Board registration: 2022/499.
Humans ; Ilium/surgery* ; Male ; Middle Aged ; Aged ; Cadaver ; Curettage/methods* ; Tissue and Organ Harvesting/methods* ; Bone Transplantation/methods* ; Adult ; Trephining/methods*

Large bone defects in load-bearing bone can result from tumor resection, osteomyelitis, trauma, and other factors. Although bone has the intrinsic potential to self-repair and regenerate, the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge. Traditionally, repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites, and autogenous bone grafting remains the "gold standard" treatment. However, the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone, donor-site morbidities, and the risk of rejection. In recent years, the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes. In addition to osteoconductivity and osteoinductivity, optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects, but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength. A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements. In this review, the use of traditional bone grafts in load-bearing bone defects, as well as their advantages and disadvantages, is summarized and reviewed. Furthermore, we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance, structural, and functional bionics to provide ideas and directions for future research.
Humans ; Bone Transplantation/methods* ; Weight-Bearing ; Bone Regeneration ; Bone Substitutes ; Bone and Bones ; Animals ; Tissue Scaffolds

Objective:To analyze the application efficacy of employing high-density porous polyethylene （Su-por） in combination with temporoparietal fascial flaps via a minimally invasive scalp incision in auricular reconstruction. Methods:This study carried out a retrospective analysis of 50 patients （50 ears in total） who underwentprimary auricular reconstruction with a Su-por scaffold in our hospital from June 2022 to January 2024. All patients underwent primary auricular reconstruction using a minimally invasive scalp incision with high-density porous polyethylene （Su-por） and temporoparietal fascial flaps. The postoperative treatment effects and complications were statistically analyzed. Results:The reconstructed ears of all patients survived. After 6 months of follow-up, the scar hyperplasia of the scalp minimally invasive incision was not obvious in any patient, and no significant hair loss was observed. The reconstructed auricle of 48 patients had a realistic shape and strong three-dimensional sense. With the extension of follow-up time, the three-dimensional structure of the auricle became clearer, and patient satisfaction increased. Among the remaining two patients, one case of flap necrosis survived after skin grafting and dressing changes. One patient had scar hyperplasia at the incision of the reconstructed ear due to a scar-prone constitution, and the shape of the auricle was not ideal, but the scar hyperplasia at the scalp incision was not obvious. Conclusion:One-stage ear reconstruction with high-density porous polyethylene （Su-por） combined with superficial temporal fascia flap through a minimally invasive scalp incision can better show the fine structure of the reconstructed ear. The minimally invasive scalp incision can effectively reduce the occurrence of scar hyperplasia and postoperative alopecia at the scalp incision.
Humans ; Plastic Surgery Procedures/methods* ; Retrospective Studies ; Surgical Flaps ; Tissue Scaffolds ; Polyethylene ; Ear Auricle/surgery* ; Male ; Scalp/surgery* ; Female ; Skin Transplantation ; Fascia/transplantation* ; Porosity ; Adult ; Middle Aged

Objective:To compare the clinical outcomes of reconstruction of oral and maxillofacial soft tissue defects using superficial circumflex iliac artery perforator flap （SCIA PF） and radial forearm free flap （RFF）. Methods:A retrospective analysis was conducted on 90 patients with head, neck, and maxillofacial tumors who were treated in our department from June 2019 to January 2024. Patients were divided into two groups based on the surgical method used: the SCIA group（n=45）, who underwent reconstruction with SCIA PF, and the RFF group（n=45）, who received RFF reconstruction. Six months postoperatively, clinical efficacy was evaluated by comparing flap swelling, flap survival rate, and patient satisfaction. Oral function was assessed using standardized scoring systems before surgery, at 1 week, 3 months, and 6 months post-surgery. Hemorheological parameters, including high-shear viscosity（shear rate 200/s）, low-shear viscosity（shear rate 30/s）, plasma viscosity, erythrocyte aggregation index, and erythrocyte sedimentation rate（ESR）, were also measured at each time point. Results:Compared with the RFF group, the SCIA group showed significantly larger flap size, longer flap harvesting and reconstruction times, earlier nasogastric tube removal and oral intake initiation, higher scores in all aspects of oral function, reduced flap edema and faster resolution, higher flap survival rates, and greater overall satisfaction （all P<0.05）. During the follow-up period （preoperative, 1 week, 3 months, and 6 months post-surgery）, hemorheological indices including high-and low-shear viscosity, plasma viscosity, erythrocyte aggregation index, and ESR progressively decreased in the SCIA group （P<0.05）. In the RFF group, these parameters improved significantly by 6 months postoperatively compared with preoperatively and 1-week postoperatively, with a notable decrease in erythrocyte aggregation index at 6 months （P<0.05）. Conclusion:Compared with RFF, SCIA PF provides larger flaps, better functional recovery, higher patient satisfaction, improved flap survival, fewer complications, and more favorable hemorheological profiles following reconstructive surgery for oral and maxillofacial defects.
Humans ; Perforator Flap/blood supply* ; Plastic Surgery Procedures/methods* ; Retrospective Studies ; Free Tissue Flaps ; Iliac Artery/transplantation* ; Forearm/surgery* ; Male ; Female ; Soft Tissue Injuries/surgery* ; Head and Neck Neoplasms/surgery* ; Middle Aged ; Treatment Outcome ; Adult

OBJECTIVE: To investigate the effectiveness of posterior lateral perforator flap in lower limb combined with free fibula for maxillary tissue defect repair. METHODS: Between December 2018 and December 2023, 16 patients with the maxillary malignant tumors were admitted. There were 10 males and 6 females, with an average age of 64.3 years (range, 54-75 years). There were 7 cases of maxillary gingival cancer, 5 cases of hard palate cancer, and 4 cases of maxillary sinus cancer. According to the 2017 American Joint Committee on Cancer (AJCC) TNM stage, there were 8 cases of stage Ⅲ, 6 cases of stage Ⅳa, and 2 cases of stage Ⅳb. After resection of the lesion, the remaining maxillary defects were classified into class Ⅱa in 3 cases, class Ⅱb in 5 cases, and class Ⅲb in 8 cases according to Brown's classification. The size of soft tissue defects ranged from 4 cm×3 cm to 8 cm×6 cm. The posterior lateral perforator flap in lower limb in size of 5 cm×4 cm-9 cm×7 cm were harvested to repair soft tissue defects, and free fibula in length of 6-11 cm were used to repair bone defects. The donor sites of the lower limb were sutured directly (6 cases) or repaired with free skin grafting (10 cases). Six patients with positive lymph node pathology were treated with radiotherapy after operation. At 6 and 12 months after operation, the self-assessment was performed by the University of Washington Quality of Survival Questionnaire Form (QUW-4) in five dimensions (facial appearance, swallowing function, chewing function, speech function, and mouth opening), and swallowing function was evaluated by using the Kubota water swallowing test. RESULTS: Postoperative pathological examination showed that all patients were squamous cell carcinoma. One patient who was treated with radiotherapy developed osteomyelitis and 1 patient developed venous crisis of skin flap. The rest of the flaps and all skin grafts survived, and the wounds healed by first intention. All patients were followed up 1-5 years (mean, 2.8 years). Two patients died of local recurrence of the tumor at the 4th and 5th years after operation, respectively. Except for the chewing function score and total score at 6 months after operation, which showed significant differences compared to preoperative scores ( P<0.05), there was no significant difference in other QUW-4 scale scores between different time points ( P>0.05). The patients' swallowing function evaluated by Kubota water swallowing test reached normal in 4 cases, suspicious in 9 cases, and abnormal in 3 cases at 6 months after operation, and 10, 6, and 0 cases at 12 months after operation, respectively. The swallowing function at 12 months was significantly better than that at 6 months ( Z=-2.382, P=0.017). CONCLUSION The posterior lateral perforator flap in the lower limb combined with free fibula to repair maxillary tissue defects can repair soft and hard tissue defects at the same time, so that the patient's facial appearance, swallowing function, chewing function, speech function, and mouth opening are satisfactorily restored and the mid-term effectiveness is good.
Humans ; Middle Aged ; Male ; Female ; Fibula/surgery* ; Aged ; Perforator Flap ; Plastic Surgery Procedures/methods* ; Maxilla/surgery* ; Maxillary Neoplasms/surgery* ; Free Tissue Flaps/transplantation* ; Lower Extremity/surgery* ; Bone Transplantation/methods* ; Treatment Outcome

OBJECTIVE: To investigate the effectiveness of delayed replantation of degloving skin preserved at 4℃ in treatment of limb degloving injuries. METHODS: Between October 2020 and October 2023, 12 patients with limb degloving injuries were admitted. All patients had severe associated injuries or poor wound conditions that prevented primary replantation. There were 7 males and 5 females; age ranged from 29 to 46 years, with an average of 39.2 years. The causes of injury included machine entanglement in 6 cases, traffic accidents in 5 cases, and sharp instrument cuts in 1 case. Time from injury to hospital admission was 0.5-3.0 hours, with an average of 1.3 hours. Injury sites included upper limbs in 7 cases and lower limbs in 5 cases. The range of degloving skin was from 5 cm×4 cm to 15 cm×8 cm, and all degloving skins were intact. The degloving skin was preserved at 4℃. After the patient's vital signs became stable and the wound conditions improved, it was trimmed into medium-thickness skin grafts for replantation. The degloving skin was preserved for 3 to 7 days. At 4 weeks after replantation, the viability of the degloving skin grafts was assessed, including color, elasticity, and sensation of pain. The Vancouver Scar Scale (VSS) was used to assess the scars of the skin grafts during follow-up. RESULTS: At 4 weeks after replantation, 8 cases of skin grafts completely survived and the color was similar with normal skin, with a survival rate of 66.67%. The elasticity of skin grafts (R0 value) ranged from 0.09 to 0.85, with an average of 0.55; moderate pain was reported in 4 cases, mild pain in 3 cases, and no pain in 5 cases. All patients were followed up 12 months. Over time, the VSS scores of all 12 patients gradually decreased, with a range of 4-11 at 12 months (mean, 6.8). CONCLUSION For limb degloving injuries that cannot be replanted immediately and do not have the conditions for deep low-temperature freezing preservation, the method of preserving the degloving skin at 4℃ for delayed replantation can be chosen.
Humans ; Male ; Adult ; Replantation/methods* ; Female ; Degloving Injuries/surgery* ; Middle Aged ; Skin Transplantation/methods* ; Treatment Outcome ; Extremities/injuries* ; Time Factors ; Skin/injuries* ; Tissue Preservation/methods*

OBJECTIVE: To prepare decellularized nerve grafts from alpha-1, 3-galactosyltransferase (GGTA1) gene-edited pigs and explore their biocompatibility for xenotransplantation. METHODS: The sciatic nerves from wild-type pigs and GGTA1 gene-edited pigs were obtained and underwent decellularization. The alpha-galactosidase (α-gal) content in the sciatic nerves of GGTA1 gene-edited pigs was detected by using IB4 fluorescence staining and ELISA method to verify the knockout status of the GGTA1 gene, and using human sciatic nerve as a control. HE staining and scanning electron microscopy observation were used to observe the structure of the nerve samples. Immunofluorescence staining and DNA content determination were used to evaluate the degree of decellularization of the nerve samples. Fourteen nude mice were taken, and subcutaneous capsules were prepared on both sides of the spine. Decellularized nerve samples of wild-type pigs ( n=7) and GGTA1 gene-edited pigs ( n=7) were randomly implanted in the subcutaneous capsules. Blood was drawn at 1, 3, 5, and 7 days after implantation to detect neutrophil counting. RESULTS: IB4 fluorescence staining and ELISA detection showed that GGTA1 gene was successfully knocked out in the nerves of GGTA1 gene-edited pigs. HE staining showed that the structure of the decellularized nerve from GGTA1 gene-edited pigs was well preserved; the nerve basement membrane tube structure was visible under scanning electron microscopy; no cell nuclei was observed, and the extracellular matrix components was retained in the nerve grafts by immunofluorescence staining; and the DNA content was significantly reduced when compared with the normal nerves ( P<0.05). In vivo experiments showed that the number of neutrophils in the two groups were similar at 1, 3, and 7 days after implantation, with no significant difference ( P>0.05); only at 5 days, the number of neutrophils was significantly lower in the GGTA1 gene-edited pigs than in the wild-type pigs ( P<0.05). CONCLUSION The decellularized nerve grafts from GGTA1 gene-edited pigs have well-preserved nerve structure, complete decellularization, retain the natural nerve basement membrane tube structure and components, and low immune response after xenotransplantation through in vitro experiments.
Animals ; Transplantation, Heterologous ; Galactosyltransferases/genetics* ; Sciatic Nerve/immunology* ; Swine ; Tissue Engineering/methods* ; Humans ; Graft Rejection/prevention & control* ; Gene Editing ; Mice ; Mice, Nude ; Heterografts/immunology* ; Animals, Genetically Modified ; Tissue Scaffolds ; Decellularized Extracellular Matrix