High Potential of Bacterial Adhesion on Block Bone Graft Materials

Experimental Study on the Application of Bioactive Xenogeneic Porcine Cancellous Bone for Cervical Intervertebral Fusion in Goats

STUDY DESIGN

An experimental study in a cervical intervertebral fusion goat model.

OBJECTIVE

To investigate the effect of bioactive xenogeneic porcine cancellous bone applied to the intervertebral fusion of goat cervical vertebrae.

SUMMARY OF BACKGROUND DATA

Although autogenous bone achieves satisfied outcome in cervical intervertebral fusion, it is limited and cause several complications. The application of xenogeneic bone has potential to solve these problems.

METHODS

Thirty local goats were randomly divided into 3 groups: group A (12 goats): autogenous tricortical iliac bone group; group B (6 goats): polyetheretherketone (PEEK) cage with autologous bone; and group C (12 goats): PEEK cage with bioactive xenogeneic porcine cancellous bone. C3-C4 discectomy was performed in each group and the above bone graft and bone graft substitutes were implanted. Lateral cervical spine x-rays were taken at preoperative; immediately postoperative; and 4, 8, 12, and 24 weeks postoperatively every goat. Disc space heights (DSHs) were measured on lateral x-rays. CT examination was performed at 12 and 24 weeks after surgery for the fusion score. After 4 and 8 weeks after surgery, 3 goats were euthanized in both groups A and C to evaluate the immune rejection response through histology. At 12 and 24 weeks after surgery, 3 goats were euthanized in each group. The cervical implants fusion outcome was evaluated through specimen histology observation.

RESULT

As time extended, the immune rejection of bioactive xenogeneic porcine cancellous bone gradually subsided. Radiology, specimen observation, and histology manifested that the C3-4 vertebral bodies of goats in each group gradually fused. All the goats in each group achieved bony fusion at 24 weeks after surgery. In terms of preventing intervertebral space collapse, the PEEK cage could achieve better results. There was no significant difference in the remaining experimental data (P>0.05).

CONCLUSIONS

Bioactive xenogeneic porcine cancellous bone can obtain satisfied fusion outcomes in cervical intervertebral fusion and is an ideal intervertebral fusion material in goats.

Traumatic Fracture Treatment: Calcium Phosphate Bone Substitute Case-Control Study in Humerus, Radius, Tibia Fractures-Assessing Efficacy and Recovery Outcomes

To date, insufficient investigation has been carried out on the biocompatibility of synthetic bioactive bone substitute materials after traumatically induced bone fractures in clinical conditions. This study encompasses the safety, resorption, healing process, and complications of surgical treatment. Our current hypothesis posits that calcium phosphate-based bone substitutes could improve bone healing. In this retrospective case-control study, over 290 patients who underwent surgical treatment for acute fractures were examined. Bone defects were augmented with calcium phosphate-based bone substitute material (CP) in comparison to with empty defect treatment (ED) between 2011 and 2018. A novel scoring system for fracture healing was introduced to assess bone healing in up to six radiological follow-up examinations. Furthermore, demographic data, concomitant diseases, and complications were subjected to analysis. Data analysis disclosed significantly fewer postoperative complications in the CP group relative to the ED group (p < 0.001). The CP group revealed decreased risks of experiencing complications (p < 0.001), arthrosis (p = 0.01), and neurological diseases (p < 0.001). The fracture edge, the fracture gap, and the articular surface were definably enhanced. Osteosynthesis and general bone density demonstrated similarity (p > 0.05). Subgroup analysis focusing on patients aged 64 years and older revealed a diminished complication incidence within the CP group (p = 0.025). Notably, the application of CP bone substitute materials showed discernible benefits in geriatric patients, evident by decreased rates of pseudarthrosis (p = 0.059). Intermediate follow-up evaluations disclosed marked enhancements in fracture gap, edge, and articular surface conditions through the utilization of CP-based substitutes (p < 0.05). In conclusion, calcium phosphate-based bone substitute materials assert their clinical integrity by demonstrating safety in clinical applications. They substantiate an accelerated early osseous healing trajectory while concurrently decreasing the severity of complications within the bone substitute cohort. In vivo advantages were demonstrated for CP bone graft substitutes.

Role of periosteum during healing of alveolar critical size bone defects in the mandible: a pilot study

OBJECTIVES

Minipigs present advantages for studying oral bone regeneration; however, standardized critical size defects (CSD) for alveolar bone have not been validated yet. The objectives of this study are to develop a CSD in the mandibular alveolar bone in Aachen minipigs and to further investigate the specific role of periosteum.

MATERIALS AND METHODS

Three female Aachen minipigs aged 17, 24, and 84 months were used. For each minipig, a split-mouth design was performed: an osteotomy (2 cm height × 2.5 cm length) was performed; the periosteum was preserved on the left side and removed on the right side. Macroscopic, cone beam computed tomography (CBCT), microcomputed tomography (µCT), and histological analyses were performed to evaluate the bone defects and bone healing.

RESULTS

In both groups, spontaneous healing was insufficient to restore initial bone volume. The macroscopic pictures and the CBCT results showed a larger bone defect without periosteum. µCT results revealed that BMD, BV/TV, and Tb.Th were significantly lower without periosteum. The histological analyses showed (i) an increased osteoid apposition in the crestal area when periosteum was removed and (ii) an ossification process in the mandibular canal area in response to the surgical that seemed to increase when periosteum was removed.

CONCLUSIONS

A robust model of CSD model was developed in the alveolar bone of minipigs that mimics human mandibular bone defects. This model allows to further investigate the bone healing process and potential factors impacting healing such as periosteum.

CLINICAL RELEVANCE

This model may be relevant for testing different bone reconstruction strategies for preclinical investigations.

Bioengineering Approaches to Fight against Orthopedic Biomaterials Related-Infections

One of the most serious complications following the implantation of orthopedic biomaterials is the development of infection. Orthopedic implant-related infections do not only entail clinical problems and patient suffering, but also cause a burden on healthcare care systems. Additionally, the ageing of the world population, in particular in developed countries, has led to an increase in the population above 60 years. This is a significantly vulnerable population segment insofar as biomaterials use is concerned. Implanted materials are highly susceptible to bacterial and fungal colonization and the consequent infection. These microorganisms are often opportunistic, taking advantage of the weakening of the body defenses at the implant surface–tissue interface to attach to tissues or implant surfaces, instigating biofilm formation and subsequent development of infection. The establishment of biofilm leads to tissue destruction, systemic dissemination of the pathogen, and dysfunction of the implant/bone joint, leading to implant failure. Moreover, the contaminated implant can be a reservoir for infection of the surrounding tissue where microorganisms are protected. Therefore, the biofilm increases the pathogenesis of infection since that structure offers protection against host defenses and antimicrobial therapies. Additionally, the rapid emergence of bacterial strains resistant to antibiotics prompted the development of new alternative approaches to prevent and control implant-related infections. Several concepts and approaches have been developed to obtain biomaterials endowed with anti-infective properties. In this review, several anti-infective strategies based on biomaterial engineering are described and discussed in terms of design and fabrication, mechanisms of action, benefits, and drawbacks for preventing and treating orthopaedic biomaterials-related infections.

Bio-Interactive Zwitterionic Dental Biomaterials for Improving Biofilm Resistance: Characteristics and Applications

Biofilms are formed on surfaces inside the oral cavity covered by the acquired pellicle and develop into a complex, dynamic, microbial environment. Oral biofilm is a causative factor of dental and periodontal diseases. Accordingly, novel materials that can resist biofilm formation have attracted significant attention. Zwitterionic polymers (ZPs) have unique features that resist protein adhesion and prevent biofilm formation while maintaining biocompatibility. Recent literature has reflected a rapid increase in the application of ZPs as coatings and additives with promising outcomes. In this review, we briefly introduce ZPs and their mechanism of antifouling action, properties of human oral biofilms, and present trends in anti-biofouling, zwitterionic, dental materials. Furthermore, we highlight the existing challenges in the standardization of biofilm research and the future of antifouling, zwitterated, dental materials.