Evaluation of efficacy of non-resorbable membranes compared to resorbable membranes in patients undergoing guided bone regeneration

Magnesium-Impregnated Membrane Promotes Bone Regeneration in Rat Skull Defect by N-Linked Glycosylation of SPARC via MagT1

Autograft has long been the gold standard for various bone surgeries. Nevertheless, the increasing usage of synthetic implants is taking over the operation rooms due to biosafety and standardized protocols. To fulfill such tremendous needs, a magnesium-impregnated membrane is devised that steadily releases magnesium ions to stimulate osteogenesis. The compatibility of Magnesium oxide (MgO) particles is enhanced through hydration and grafting, characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). With detailed degradation profiles, an in-depth investigation of Magnesium transporter 1 (MagT1) for magnesium intake is carried out and engaging in the N-linked glycosylation by using RNAi and inhibitors. The glycosylation of secreted protein acidic and rich in cysteine (SPARC) affected extracellular secretion and mineral deposition, demonstrated by immunostaining and density-dependent color-SEM (DDC-SEM). Skull defects are treated by implanting magnesium-impregnated membranes in rats and evaluated them by micro-CT and histological exams. This study revealed the compatible integration of grafted magnesium hydroxide (g-MH) particles is the key to functional performance and critical to applicability in vivo; meanwhile, it opens the door to a biological rationale for designing biomimetic materials.

Guided Bone Regeneration in the Posterior Mandible Using a Resorbable Metal Magnesium Membrane and Fixation Screws: A Case Report

Background: Due to bone loss, implant placement in the posterior mandible is often impossible without prior augentative procedures. The reconstruction of bone defects with horizontal and vertical components using particulated bone grafts requires the placement of a mechanically stable structure for stabilization of the grafting material. Although titanium-reinforced membranes and titanium meshes have been shown to be effective in this indication, the necessity of their removal, often in a separate surgical procedure, is seen as a disadvantage. Since the introduction of a new resorbable magnesium metal membrane and fixation screw, a mechanically stable and resorbable system might provide an alternative option for guided bone regeneration (GBR) in the posterior mandible. Case Presentation: A 61-year-old patient was presented with large edentulous areas in all posterior regions and requested fixed dentures in Areas 34-36. Tooth 33 was extracted and treated with an immediate implantation of a ceramic implant, whereas Positions 34-36 were treated with a two-stage approach. The site was augmented horizontally, with a slight vertical component using autologous and allogenic bone and a new completely resorbable magnesium metal membrane and fixation screw. During the initial healing period, the patient reported a tingling sensation at the site of the augmentation. This is an observation that is specific to the magnesium products and is potentially caused by the release of hydrogen gas as the metal degrades and is resorbed. Upon re-entry at 3 months, it was clinically observed that there was a very dense and vascularized bone that was sufficient for placing two 5.5 × 10 mm ceramic dental implants. Conclusion: A completely resorbable magnesium membrane and fixation screw were able to support the bony regeneration in a large GBR situation in the posterior mandible. Due to the use of a new material for GBR, different clinical observations were made compared to the standard material choices.

Dental implant placement with simultaneous localized ridge augmentation using L-shaped titanium mesh in the esthetic zone: a case report

The aim of this case report is to illustrate a successful technique for dental implant placement in the esthetic zone using simultaneous localized ridge augmentation with L-shaped titanium mesh. A 35-year-old patient presented with a single missing tooth in the esthetic zone requiring dental implant placement. The treatment plan was made to place a dental implant in conjunction with a guided bone regeneration procedure using a prefabricated L-shaped titanium mesh. The procedure achieved successful reconstruction of the deficient ridge, providing ample volume and contour for implant placement. Implant osteointegration was achieved, resulting in a satisfactory functional and esthetically pleasing outcome. The use of L-shaped titanium mesh offers superior stability and biocompatibility, ensuring optimal support and containment of graft material. This case report highlights the feasibility and clinical effectiveness of dental implant placement with simultaneous localized ridge augmentation using L-shaped titanium mesh in the esthetic zone. Further studies are warranted to assess the long-term success and esthetic outcomes of this technique.

Recent Advances in Scaffolds for Guided Bone Regeneration

The rehabilitation of alveolar bone defects of moderate to severe size is often challenging. Currently, the therapeutic approaches used include, among others, the guided bone regeneration technique combined with various bone grafts. Although these techniques are widely applied, several limitations and complications have been reported such as morbidity, suboptimal graft/membrane resorption rate, low structural integrity, and dimensional stability. Thus, the development of biomimetic scaffolds with tailor-made characteristics that can modulate cell and tissue interaction may be a promising tool. This article presents a critical consideration in scaffold's design and development while also providing information on various fabrication methods of these nanosystems. Their utilization as delivery systems will also be mentioned.

Assessment of Postoperative Edema in Different Bone Graft Cases in Vertical Defects in Periodontal Surgery: An Original Research

Background

To replace missing periodontal tissues in vertical defects during periodontal surgery, bone graft materials are frequently used. A frequent occurrence that can affect healing outcomes is postoperative edema. The purpose of this study was to evaluate postoperative edema in various vertical bone graft defects following periodontal surgery.

Materials and Methods

50 participants were split into two groups for a prospective study: Group A received xenografts, whereas Group B received synthetic grafts. Up to 14 days after surgery, baseline and routine postoperative edema measurements were made. Edema levels in each group were compared using statistical analysis.

Results

At all postoperative time points, Group A showed substantially more edema than Group B (P < 0.05). Furthermore, edema persisted longer in Group A than it did in Group B.

Conclusion

In conclusion, the substance of the bone graft used in vertical defects during periodontal surgery affects postoperative edema. Compared to synthetic grafts, xenografts caused swelling to last longer and at higher levels. To maximize healing results, clinicians should take these findings into account when choosing graft materials.

Resorbable GBR Scaffolds in Oral and Maxillofacial Tissue Engineering: Design, Fabrication, and Applications

Guided bone regeneration (GBR) is a promising technique in bone tissue engineering that aims to replace lost or injured bone using resorbable scaffolds. The promotion of osteoblast adhesion, migration, and proliferation is greatly aided by GBR materials, and surface changes are critical in imitating the natural bone structure to improve cellular responses. Moreover, the interactions between bioresponsive scaffolds, growth factors (GFs), immune cells, and stromal progenitor cells are essential in promoting bone regeneration. This literature review comprehensively discusses various aspects of resorbable scaffolds in bone tissue engineering, encompassing scaffold design, materials, fabrication techniques, and advanced manufacturing methods, including three-dimensional printing. In addition, this review explores surface modifications to replicate native bone structures and their impact on cellular responses. Moreover, the mechanisms of bone regeneration are described, providing information on how immune cells, GFs, and bioresponsive scaffolds orchestrate tissue healing. Practical applications in clinical settings are presented to underscore the importance of these principles in promoting tissue integration, healing, and regeneration. Furthermore, this literature review delves into emerging areas of metamaterials and artificial intelligence applications in tissue engineering and regenerative medicine. These interdisciplinary approaches hold immense promise for furthering bone tissue engineering and improving therapeutic outcomes, leading to enhanced patient well-being. The potential of combining material science, advanced manufacturing, and cellular biology is showcased as a pathway to advance bone tissue engineering, addressing a variety of clinical needs and challenges. By providing this comprehensive narrative, a detailed, up-to-date account of resorbable scaffolds' role in bone tissue engineering and their transformative potential is offered.

In vivo evaluation of bone regeneration using ZIF8-modified polypropylene membrane in rat calvarium defects

AIM

The profound potential of zeolitic imidazolate framework 8 (ZIF8) thin film for inducing osteogenesis has been previously established under in vitro conditions. As the next step towards the clinical application of ZIF8-modified substrates in periodontology, this in vivo study aimed to evaluate the ability of the ZIF8 crystalline layer to induce bone regeneration in an animal model defect.

MATERIALS AND METHODS

Following the mechanical characterization of the membranes and analysing the in vitro degradation of the ZIF8 layer, in vivo bone regeneration was evaluated in a critical-sized (5-mm) rat calvarial bone defect model. For each animal, one defect was randomly covered with either a polypropylene (PP) or a ZIF8-modified membrane (n = 7 per group), while the other defect was left untreated as a control. Eight weeks post surgery, bone formation was assessed by microcomputed tomography scanning, haematoxylin and eosin staining and immunohistochemical analysis.

RESULTS

The ZIF8-modified membrane outperformed the PP membrane in terms of mechanical properties and revealed a trace Zn+2 release. Results of in vivo evaluation verified the superior barrier function of the ZIF8-coated membrane compared with pristine PP membrane. Compared with the limited marginal bone formation in the control and PP groups, the defect area was almost filled with mature bone in the ZIF8-coated membrane group.

CONCLUSIONS

Our results support the effectiveness of the ZIF8-coated membrane as a promising material for improving clinical outcomes of guided bone regeneration procedures, without using biological components.