The evaluation of blood compatibility of biomaterials is crucial for ensuring the clinical safety of implantable medical devices. To address the limitations of traditional testing methods in real-time monitoring and electrical property analysis, this study developed a portable electrical impedance tomography (EIT) system. The system uses a 16-electrode design, operates within a frequency range of 1 to 500 kHz, achieves a signal to noise ratio (SNR) of 69.54 dB at 50 kHz, and has a data collection speed of 20 frames per second. Experimental results show that the EIT system developed in this study is highly consistent with a microplate reader ( R ²=0.97) in detecting the hemolytic behavior of industrial-grade titanium (TA3) and titanium alloy-titanium 6 aluminum 4 vanadium (TC4) in anticoagulated bovine blood. Additionally, with the support of a multimodal image fusion Gauss-Newton one-step iterative algorithm, the system can accurately locate and monitor in real-time the dynamic changes in blood permeation and coagulation caused by TC4 in vivo. In conclusion, the EIT system developed in this study provides a new and effective method for evaluating the blood compatibility of biomaterials.
Electric Impedance ; Animals ; Tomography/instrumentation* ; Biocompatible Materials ; Materials Testing/instrumentation* ; Cattle ; Titanium ; Alloys ; Prostheses and Implants

This review article summarizes the current modification methods employed to enhance the osseointegration properties of polyetheretherketone (PEEK), a novel biomaterial. Our analysis highlights that strategies such as surface treatment, surface modification, and the incorporation of bioactive composites can markedly improve the bioactivity of PEEK surfaces, thus facilitating their effective integration with bone tissue. However, to ensure widespread application of PEEK in the medical field, particularly in oral implantology, additional experiments and long-term clinical evaluations are required. Looking ahead, future research should concentrate on developing innovative modification techniques and assessment methodologies to further optimize the performance of PEEK implant materials. The ultimate goal is to provide the clinical setting with even more reliable solutions.
Benzophenones ; Ketones/chemistry* ; Polyethylene Glycols/chemistry* ; Osseointegration ; Humans ; Polymers ; Biocompatible Materials/chemistry* ; Surface Properties ; Prostheses and Implants ; Dental Implants

Dynamic navigation technology can "real-time guide" the implantologist to place the implant in the alveolar bone of the missing tooth area according to the preoperative design of the optimal site and path, making the whole implant surgery process more safe and precise. In order to further promote the standardized application of oral implant dynamic navigation technology, China Association of Gerontology and Geriatrics has convened distinguished experts to engage in deliberations and develop the standard. This standard covers the basic requirements, indications and contraindications, operation procedures, common complications and treatment measures, and accuracy verification. This standard can be used as a reference for the use of dynamic navigation technology in implant surgery.
Humans ; Dental Implantation, Endosseous/standards* ; Surgery, Computer-Assisted/standards* ; Dental Implants ; Surgical Navigation Systems/standards*

OBJECTIVE: To analyze the effectiveness of single three-dimensional (3D)-printed microporous titanium prostheses and flap combined prostheses implantation in the treatment of large segmental infectious bone defects in limbs. METHODS: A retrospective analysis was conducted on the clinical data of 76 patients with large segmental infectious bone defects in limbs who were treated between January 2019 and February 2024 and met the selection criteria. Among them, 51 were male and 25 were female, with an age of (47.7±9.4) years. Of the 76 patients, 51 had no soft tissue defects (single prostheses group), while 25 had associated soft tissue defects (flap combined group). The single prostheses group included 28 cases of tibial bone defects, 11 cases of femoral defects, 5 cases of humeral defects, 4 cases of radial bone defects, and 3 cases of metacarpal, or carpal bone defects, with bone defect length ranging from 3.5 to 28.0 cm. The flap combined group included 3 cases of extensive dorsum of foot soft tissue defects combined with large segmental metatarsal bone defects, 19 cases of lower leg soft tissue defects combined with large segmental tibial bone defects, and 3 cases of hand and forearm soft tissue defects combined with metacarpal, carpal, or radial bone defects, with bone defect length ranging from 3.8 to 32.0 cm and soft tissue defect areas ranging from 8 cm×5 cm to 33 cm×10 cm. In the first stage, vancomycin-loaded bone cement was used to control infection, and flap repair was performed in the flap combined group. In the second stage, 3D-printed microporous titanium prostheses were implanted. Postoperative assessments were performed to evaluate infection control and bone integration, and pain release was evaluated using the visual analogue scale (VAS) score. RESULTS: All patients were followed up postoperatively, with an average follow-up time of (35.2±13.4) months. In the 61 lower limb injury patients, the time of standing, walk with crutches, and fully bear weight were (2.2±0.6), (3.9±1.1), and (5.4±1.1) months, respectively. The VAS score at 1 year postoperatively was significantly lower than preoperative one ( t=-10.678, P<0.001). At 1 year postoperatively, 69 patients (90.8%) showed no complication such as infection, fracture, prosthesis displacement, or breakage, and X-ray films indicated good integration at the prosthesis-bone interface. According to the Paley scoring system for the healing of infectious bone defects, the results were excellent in 37 cases, good in 29 cases, fair in 3 cases, and poor in 7 cases. In the single prostheses group, during the follow-up, there was 1 case each of femoral prostheses fracture, femoral infection, and tibial infection, with a treatment success rate of 94.1% (48/51). In lower limb injury patients, the time of fully bear weight was (5.0±1.0) months. In the flap combined group, during the follow-up, 1 case of tibial fixation prostheses screw fracture occurred, along with 2 cases of recurrent foot infection in diabetic patients and 1 case of tibial infection. The treatment success rate was 84.0% (21/25). The time of fully bear weight in lower limb injury patients was (5.8±1.2) months. The overall infection eradication rate for all patients was 93.4% (71/76). CONCLUSION The use of 3D-printed microporous titanium prostheses, either alone or in combination with flaps, for the treatment of large segmental infectious bone defects in the limbs results in good effectiveness with a low incidence of complications. It is a feasible strategy for the reconstruction of infectious bone defects.
Humans ; Male ; Female ; Middle Aged ; Printing, Three-Dimensional ; Titanium ; Retrospective Studies ; Surgical Flaps ; Adult ; Prosthesis Implantation/methods* ; Plastic Surgery Procedures/methods* ; Treatment Outcome ; Prostheses and Implants ; Bone Diseases, Infectious/surgery* ; Extremities/surgery* ; Prosthesis Design

OBJECTIVE: To optimize the perioperative management experiences for breast cancer patients undergoing direct-to-implant-based breast reconstruction, and provide reference for clinical practice. METHODS: A comprehensive review of recent domestic and international literature was conducted to systematically summarize the key points of perioperative management for direct-to-implant-based breast reconstruction, including preoperative health education, intraoperative strategies, and postoperative management measures, along with an introduction to the clinical experiences of West China Hospital of Sichuan University. RESULTS: Standardized perioperative management can effectively reduce the incidence of complications and achieve excellent cosmetic outcomes and quality of life after operation. Preoperative management includes proactive health education to alleviate patients' anxiety and improve treatment compliance, as well as comprehensive assessment by surgeons of the patient's physical condition and reconstructive expectations to select the most appropriate implant. Intraoperative management consists of strict aseptic technique, minimizing implant exposure, preserving blood supply to the nipple-areola complex (e.g., by using minimally invasive techniques or indocyanine green angiography, etc), and meticulous hemostasis. Postoperative management encompasses multimodal analgesia, individualized drain management (such as early removal or retaining a small amount of fluid to optimize contour), infection prevention and control (including topical and systemic antibiotics, ultrasound-guided minimally invasive drainage), guidance on rehabilitation exercises (early activity restriction followed by gradual recovery), and regular follow-up to evaluate aesthetic results and monitor for complications. CONCLUSION Establishing a standardized, multidisciplinary perioperative management framework markedly enhances surgical safety and patient satisfaction, thereby providing a replicable benchmark for direct-to-implant-based breast reconstruction across diverse clinical settings.
Humans ; Female ; Breast Neoplasms/surgery* ; China ; Perioperative Care/methods* ; Breast Implants ; Mammaplasty/methods* ; Breast Implantation/methods* ; Postoperative Complications/prevention & control* ; Quality of Life ; Mastectomy

OBJECTIVE: To investigate the effectiveness of three-dimensional (3D) printed customized hemi-pelvic prosthesis for pelvic reconstruction after resection of massive pelvic tumors. METHODS: A retrospective analysis was conducted on 26 patients with massive pelvic tumors who met the selection criteria and were treated between November 2021 and May 2024. The cohort included 11 males and 15 females, with a mean age of 52.65 years (range, 17-73 years). Histopathological diagnoses were as follows: 9 cases of chondrosarcoma, 2 of undifferentiated pleomorphic sarcoma, 4 of spindle cell sarcoma, 2 of osteosarcoma, 1 of solitary fibrous tumor, 1 of myxoid chondroma, 1 of malignant peripheral nerve sheath tumor, 1 of chondromyxoid epithelioma, and 5 of metastatic malignant tumors. According to the Enneking classification, tumor involvement was distributed as 4 cases in zones Ⅰ+Ⅱ, 9 in zones Ⅱ+Ⅲ, 3 in zones Ⅰ+Ⅳ, 8 in zones Ⅰ+Ⅱ+Ⅲ, and 2 in zones Ⅰ+Ⅱ+Ⅳ. The disease duration ranged from 3 to 40 months, with a mean of 9.85 months. All patients underwent reconstruction with customized 3D-printed hemi-pelvic prostheses. The effectiveness was evaluated by Musculoskeletal Tumor Society (MSTS) score and Harris hip score before operation and at last follow-up, and pain levels were evaluated by visual analogue scale (VAS) score before operation, at 3 months after operation, and at last follow-up. RESULTS: The operation time ranged from 186 to 528 minutes, with a mean of 334.58 minutes. The intraoperative blood loss ranged from 1 400 to 4 000 mL, with a mean of 2173.08 mL, and the transfusion volume ranged from 750 to 3 500 mL, with a mean of 1 659.62 mL. All 26 patients were followed up 10-42 months (mean, 18.5 months). Postoperative complications included prosthetic dislocation in 2 cases, which were attributed to improper positioning during home care and an accidental fall, respectively. One patient developed a vesicocutaneous fistula and poor wound healing due to pre-existing tumor invasion into the bladder. One patient experienced failure and loosening of the internal fixation at 8 months after operation caused by local tumor recurrence, and subsequently died at 14 months postoperatively due to progression of brain metastases. Postoperative complications such as poor healing of incisions, prosthetic dislocation, or failure of internal fixation was not observed in the remaining patients. At last follow-up, the walking ability of most patients recovered to varying degrees. The VAS scores at 3 months and at last follow-up significantly improved when compared with those before operation, and the scores at last follow-up further improved when compared with 3 months after operation, all showing significant differences ( P<0.05). The MSTS scores and Harris scores at last follow-up were significantly higher than those before operation ( P<0.05). CONCLUSION 3D printed customized hemi-pelvic prosthesis is effective for reconstruction of massive pelvic tumors after resection, but there are still some limitations, and soft tissue reconstruction should be paid attention to.
Humans ; Printing, Three-Dimensional ; Female ; Male ; Adult ; Plastic Surgery Procedures/methods* ; Retrospective Studies ; Middle Aged ; Aged ; Pelvic Bones/surgery* ; Bone Neoplasms/surgery* ; Adolescent ; Pelvic Neoplasms/surgery* ; Prosthesis Design ; Young Adult ; Treatment Outcome ; Prostheses and Implants

OBJECTIVE: To investigate the biocompatibility of porous WE43 magnesium alloy scaffolds manufactured by 3D printing technology and to observe its effect in treating femoral defects in New Zealand white rabbits. METHODS: In vitro cytotoxicity test was performed using bone marrow mesenchymal stem cells from Sprague Dawley (S-D) rats. According to the different culture media, the cells were divided into 100% extract group, 50% extract group, 10% extract group and control group. After culturing for 1, 3 and 7 days, the cell activity of each group was determined by cell counting kit-8 (CCK-8). In the in vivo experiment, 3.0-3.5 kg New Zealand white rabbits were randomly divided into three groups: Experimental group, bone cement group and blank group, with 9 rabbits in each group. Each rabbit underwent surgery on the left lateral femoral condyle, and a bone defect with a diameter of 5 mm and a depth of 6 mm was created using a bone drill. The experimental group was implanted with WE43 magnesium alloy scaffolds, the bone cement group was implanted with calcium sulfate bone cement, and the blank group was not implanted. Then 4, 8 and 12 weeks after surgery, 3 rabbits in each group were euthanized by carbon dioxide anesthesia, and the femur and important internal organs were sampled. Micro-computed tomography (Micro-CT) scanning was performed on the left lateral femoral condyle. Sections of important internal organs were prepared and stained with hematoxylin-eosin (HE). Hard tissue sections were made from the left lateral femoral condyle and stained with methylene blue acid fuchsin and observed under a microscope. RESULTS: In the cytotoxicity test, the cell survival rate in the 100% extract group was higher than that in the control group (140.56% vs. 100.00%, P < 0.05) on 1 day of culture; there was no statistically significant difference (P>0.05) in cell survival rate among the groups on 3 days of culture; the cell survival rate in the 100% extract group was lower than that in the control group (68.64% vs. 100.00%, P < 0.05) on 7 days of culture. Micro-CT scanning in the in vivo experiment found that most of the scaffolds in the experimental group had been degraded in 4 weeks, with very few high-density scaffolds remaining. In 12 weeks, there was no obvious stent outline. In 4 weeks, a certain amount of gas was generated around the WE43 magnesium alloy scaffold, and the gas was significantly reduced from 8 to 12 weeks. Hard tissue sections showed that a certain amount of extracellular matrix and osteoid were generated around the scaffolds in the experimental group in 4 weeks. In the bone cement group, most of the calcium sulfate bone cement had been degraded. In 8 weeks, the osteoid around the scaffold and its degradation products in the experimental group increased significantly. In 12 weeks, new bone was in contact with the scaffold around the scaffold in the experimental group. There was less new bone in the bone cement group and the blank group. CONCLUSION The porous WE43 magnesium alloy scaffold fabricated by 3D printing process has good biocompatibility and good osteogenic properties, and has the potential to become a new material for repairing bone defects.
Animals ; Rabbits ; Printing, Three-Dimensional ; Alloys/chemistry* ; Tissue Scaffolds/chemistry* ; Magnesium/chemistry* ; Rats, Sprague-Dawley ; Biocompatible Materials ; Mesenchymal Stem Cells/cytology* ; Femur/surgery* ; Rats ; Absorbable Implants ; Male ; Bone Regeneration ; Tissue Engineering/methods* ; Cells, Cultured

OBJECTIVE: To observe the long-term health condition of the single-tooth dental implant at the first molar site, and to evaluate the related factors affecting the peri-implant health. METHODS: In this study, 82 patients who were treated in the Second Clinical Division, Peking University School and Hos-pital of Stomatology from January 2008 to December 2020 were enrolled. Peri-implant tissue conditions were assessed by clinical and radiographic examination. The peri-implant probing depth (PPD), modified sulcus bleeding index (mSBI), modified plaque index (mPLI) and papilla index (PI) were recorded for 278 implants. The X-ray analysis included the restoration emergence angle (REA), the clinical crown-implant ratio (cC/I), the horizontal tooth-implant distance (HTID), the contact point level (CPL) and the embrasure surface area (ESA), etc. Kruskal-Wallis rank sum test and generalized estimation equation were used for statistical analysis. RESULTS: The average age of the patients was (40.2±9.5) years (19 to 84 years), with 33 males and 49 females. The follow-up time was (4.9±3.3) years (1 to 10 years). According to the diagnostic criteria in 2018, the prevalence of peri-implantitis in this study was 14.03% on the implant level and 21.95% on the patient level. The peri-implant health rate was 19.06% on the implant level and 18.29% on the patient level. The prevalence of peri-implant mucositis was 66.91% on the implant level and 59.75% on the patient level. At the baseline, there were statistically significant differences between the peri-implant health group and peri-implantitis group in PPD, distal HTID and mesial/distal CPL, cC/I (P < 0.05), while there was no statistically significant difference in mSBI, mPLI, PI, mesial HTID, mesial/distal REA and mesial/distal ESA between the two groups. Among the differences between follow-up and baseline, there were statistically significant dif-ferences between the two groups in PPD, mesial/distal HTID, mesial/distal CPL and mesial/distal ESA (P < 0.05). Generalized estimation equation showed that PPD, mesial/distal HTID, mesial CPL, and mesial ESA had significant positive correlations with the risk of peri-implantitis in the difference between baseline and follow-up. CONCLUSION Based on the results of this study, the peri-implant health rate is still unsatisfied, and the PPD, HTID, CPL, ESA may be related to the long-term health of the implant.
Humans ; Male ; Female ; Middle Aged ; Adult ; Dental Implants, Single-Tooth/adverse effects* ; Aged ; Aged, 80 and over ; Periodontal Index ; Young Adult ; Peri-Implantitis/epidemiology*

OBJECTIVE: To assess the osteogenesis height in maxillary sinus segment one year after zygomatic implantation by imaging methods, and evaluate the influence of patient factors, maxillary sinus anatomical factors and surgical factors on postoperative osteogenesis height. METHODS: This study is a retrospective study, including patients who underwent zygomatic implantation and whose zygomatic implants passed through the maxillary sinus at the Department of Implantology, Peking University School and Hospital of Stomatology from July 2017 to January 2022. Preoperative and postoperative cone beam CT (CBCT)was taken to measure and calculate the average osteogenesis height (AOH) in maxillary sinus segment of the zygomatic implants, then the residual bone height, the width and morphology of the maxillary sinus floor in the buccal and palatal directions were measured. Besides, the integrity of Schneiderian membrane during implant surgery, and the general information of the patients and zygomatic implants were recorded. By comparing anatomical situations and surgical characteristics, the differences of AOH under different conditions were analyzed. Then AOH was divided into two groups (obvious osteogenesis group and non-obvious osteogenesis group) using the median as the threshold, and the influencing factors of osteogenesis were evaluated using mixed effect generalized linear model univariable and multivariable analysis. RESULTS: A total of 47 zygomatic implants were implanted in 24 patients. During the average follow-up period of 12.1 months, there was no implant failure, and the implant survival rate was 100%. Postoperative CBCT showed that 43 zygomatic implants had osteogenic images in the maxillary sinus segment, most of which originated from the floor of the maxillary sinus, and the median AOH was 3.1 mm [interquartile range (IQR): 4.0 mm]. In terms of maxillary sinus width, there were 31 cases (66.0%) of wide type and 16 cases (34.0%) of narrow type. In the aspect of buccal and palatal morphology, 17 cases were taper (36.2%), 20 cases were round (42.6%), and 10 cases were flat (21.3%). The median of residual bone height was 2.8 mm (IQR: 2.2 mm) before operation. Univa-riate analysis of mixed effect generalized linear model showed that postoperative obvious osteogenic rate was related to the residual bone height (OR=2.09, P=0.006). Multivariate analysis showed that the resi-dual bone height (OR=2.55, P=0.022) and the shape of a taper maxillary sinus (OR=11.44, P=0.040) had a significant impact on the postoperative obvious osteogenic rate. CONCLUSION The maxillary sinus floor showed osteogenic images 1 year after the zygomatic implantation surgery. Larger residual bone height and the shape of a taper maxillary sinus may be favorable factors for osteogenesis.
Humans ; Maxillary Sinus/surgery* ; Cone-Beam Computed Tomography ; Retrospective Studies ; Zygoma/diagnostic imaging* ; Male ; Female ; Osteogenesis/physiology* ; Middle Aged ; Adult ; Dental Implants ; Aged ; Dental Implantation, Endosseous/methods*

Cleaning process validation is an important guarantee for implantable medical devices to ensure product cleanliness. In the manufacturing process, implantable devices usually need to control pollution through cleaning process to achieve a certain cleanliness to ensure the effectiveness of sterilization and product safety. This paper discusses the cleaning process validation of the manufacturing process of the implantable devices based on relevant regulations and technical standards, and proposes the influencing factors and principles to be considered in the cleaning process validation, so as to provide technical reference for the design of the cleaning process validation.
Prostheses and Implants ; Sterilization ; Equipment and Supplies