Therapies using human mesenchymal stem cells (MSCs) combined with three-dimensional (3D) printed scaffolds are a promising strategy for bone grafting. But the harvest of MSCs still remains invasive ...for patients. Human synovial fluid MSCs (hSF-MSCs), which can be obtained by a minimally invasive needle-aspiration procedure, have been used for cartilage repair. However, little is known of hSF-MSCs in bone regeneration. Polyetherketoneketone (PEKK) is an attractive bone scaffold due to its mechanical properties comparable to bone. In this study, 3D-printed PEKK scaffolds were fabricated using laser sintering technique. hSF-MSCs were characterized and cultured on PEKK to evaluate their cell attachment, proliferation, and osteogenic potential. Rabbit calvarial critical-sized bone defects were created to test the bone regenerative effect of PEKK with hSF-MSCs. In vitro results showed that hSF-MSCs attached, proliferated, and were osteogenic on PEKK. In vivo results indicated that PEKK seeded with hSF-MSCs regenerated twice the amount of newly formed bone when compared to PEKK seeded with osteogenically-induced hSF-MSCs or PEKK scaffolds alone. These results suggested that there was no need to induce hSF-MSCs into osteoblasts prior to their transplantations in vivo. In conclusion, the combined use of PEKK and hSF-MSCs was effective in regenerating critical-sized bone defects.
Pediatric patients with Osteogenesis Imperfecta (OI), a heritable connective tissue disorder, frequently suffer from long bone deformations. Surgical correction often results in bone non-unions, ...necessitating revision surgery with autogenous bone grafting using bone-marrow-derived stem cells (BM-SC) to regenerate bone. BM-SC harvest is generally invasive and limited in supply; thus, adipose tissue's stromal vascular fraction (SVF) has been introduced as an alternative stem cell reservoir. To elucidate if OI patients' surgical site dissected adipose tissue could be used as autologous bone graft in future, we investigated whether the underlying genetic condition alters SVF's cell populations and in vitro differentiation capacity. After optimizing SVF isolation, we demonstrate successful isolation of SVF of pediatric OI patients and non-OI controls. The number of viable cells was comparable between OI and controls, with about 450,000 per gram tissue. Age, sex, type of OI, disease-causing collagen mutation, or anatomical site of harvest did not affect cell outcome. Further, SVF-containing cell populations were similar between OI and controls, and all isolated SVF's demonstrated chondrogenic, adipogenic, and osteogenic differentiation capacity in vitro. These results indicate that SVF from pediatric OI patients could be used as a source of stem cells for autologous stem cell therapy in OI.
Autogenous partially demineralized dentin matrix (APDDM) has been reportedly used as a superior bone graft material. A 52-year-old Japanese man who exhibited severe periodontitis was referred for ...oral rehabilitation. He underwent wide-range anterior maxillary alveolar bone and bilateral sinus floor augmentation by grafting of a mixture of APDDM and particulate cancellous bone and marrow (PCBM); subsequently, he underwent implant-supported full arch rehabilitation. He has been followed up for 4 years after placement of the final restoration without any complications, and his physiological bone volume has been maintained. APDDM constitutes an alternative treatment that may increase the volume of graft material and might prevent rapid resorption of PCBM, because APDDM served as a scaffold for osteoblasts from PCBM. When possible, it may be useful to apply APDDM as a graft material with PCBM for large-volume alveolar bone regeneration.
Abstract
Gene-activated matrix (GAM) has a potential usefulness in bone engineering as an alternate strategy for the lasting release of osteogenic proteins but efficient methods to generate non-viral ...GAM remain to be established. In this study, we investigated whether an atelocollagen-based GAM containing naked-plasmid (p) DNAs encoding microRNA (miR) 20a, which may promote osteogenesis in vivo via multiple pathways associated with the osteogenic differentiation of mesenchymal stem/progenitor cells (MSCs), facilitates rat cranial bone augmentation. First, we confirmed the osteoblastic differentiation functions of generated pDNA encoding miR20a (pmiR20a) in vitro, and its transfection regulated the expression of several of target genes, such as Bambi1 and PPARγ, in rat bone marrow MSCs and induced the increased expression of BMP4. Then, when GAMs fabricated by mixing 100 μl of 2% bovine atelocollagen, 20 mg β-TCP granules and 0.5 mg (3.3 μg/μl) AcGFP plasmid-vectors encoding miR20a were transplanted to rat cranial bone surface, the promoted vertical bone augmentation was clearly recognized up to 8 weeks after transplantation, as were upregulation of VEGFs and BMP4 expressions at the early stages of transplantation. Thus, GAM-based miR delivery may provide an alternative non-viral approach by improving transgene efficacy via a small sequence that can regulate the multiple pathways.
To date, therapeutic method for in vivo gene delivery has not been established on bone engineering though its potential usefulness has been suggested. For clinical applications, an effective ...condition should be developed to transfer the genes in vivo without any transfection reagents or virus vectors. In this study, to facilitate the clinical setting of this strategy, particularly aimed at atrophic bone repair, we simply investigated whether manufactured gene-activated matrix (GAM) with atelocollagen containing a certain amount of plasmid (p) DNA encoding osteogenic proteins could augment the cranial bone in rat. GAMs were manufactured by mixing 0.02, 0.1, or 1 mg of AcGFP plasmid vectors harboring cDNA of BMP4 (pBMP4) or Runx2 (pRunx2) with 2% bovine atelocollagen and β-tricalcium phosphate granules. Before manufacturing GAMs, to determine the biological activity of generated pDNAs, we confirmed GFP expression and increased level of alkaline phosphatase activities in MC3T3-E1 cells transfected with pBMP4 or pRunx2 during culture. Then, GAMs were lyophilized and transplanted to onlay placement on the cranium. At 2 weeks of transplantation, GFP-expressing cells could be detectable in only GAMs containing 1 mg of AcGFP plasmid vectors. Then, at 4 weeks, significant bone formation was recognized in GAMs containing 1 mg of pDNAs encoding BMP4 or Runx2 but not in 0.02 or 0.1 mg of GAMs. These newly formed bone tissues surrounded by osteocalcin-stained area were augmented markedly until 8 weeks after transplantation. In contrast, minimal bone formation was observed in GAMs without harboring cDNA of osteogenic proteins. Meanwhile, when GAMs were transplanted to the cranial bone defect, bone formation was detectable in specimens containing 1 mg of pBMP4 or pRunx2 at 8 weeks as well. Thus, atelocollagen-based GAM reliably could form the engineered bone even for the vertical augmentation when containing a certain amount of plasmid vectors encoding osteogenic proteins. This study supports facilitating the clinical application of GAM for bone engineering.
Posterior disc displacement (PDD) is a rare temporomandibular joint disorder. PDD without reduction sometimes causes malocclusion. Splint therapy, arthrocentesis and manipulation are sometimes ...undertaken to reposition the disc in PDD without reduction. However, these treatment strategies are not always effective for chronic PDD without reduction. Here, we report a case of a 36-year-old Japanese male who presented with malocclusion with an anterior open bite. He was diagnosed with chronic PDD without reduction, and underwent a discectomy. His occlusion improved after surgery and became stable. This case suggests that a discectomy is an effective treatment option for malocclusion with anterior open bite caused by chronic PDD without reduction.
Purpose
Metal removable partial dentures (RPDs) are often considered long‐term treatment options for partially edentulous patients, while acrylic resin RPDs are considered interim treatments. The aim ...of this review was to compare metal and acrylic resin RPDs regarding patient‐reported outcomes for partially edentulous individuals.
Materials and Methods
Four databases (MEDLINE, EMBASE, CENTRAL, and Web of Science) were systematically searched for observational studies and randomized controlled trials comparing patient‐reported outcomes between metal and acrylic resin RPDs. The primary outcome was patient satisfaction. Included studies were assessed for risk of bias using the Cochrane risk of bias in nonrandomized studies of interventions tool (ROBINS‐I) and the Cochrane Collaboration Risk of Bias Tool for Randomized Controlled Trials. The level of evidence was evaluated using Oxford Center for Evidence‐based Medicine tool. A random‐effects model was used to analyze the data.
Results
A total of 15 studies were included in the systematic review; 10 in the meta‐analysis. The pooled effect size for patient satisfaction and oral health‐related quality of life showed no statistical significant difference between metal and acrylic resin dentures (0.22, 95% confidence interval –0.01, 0.45, p = 0.06; 1.45, 95% confidence interval –2.43, 5.33, p = 0.46, respectively). Compliance with using RPDs was significantly higher in patients with metal compared to patients with acrylic resin dentures (pooled odds ratio = 0.57, 95% confidence interval 0.45, 0.73, p < 0.001). Most studies had critical to serious risk of bias and low level of evidence.
Conclusions
The reviewed studies showed that there was no significant difference between metal and acrylic resin RPDs in patient satisfaction and oral health‐related quality of life. Metal dentures were associated with higher patient compliance rates and were preferred more by patients compared to acrylic resin dentures. However, the reviewed studies had low levels of evidence and therefore, high‐quality randomized controlled trials are needed to conclusively address the question of this review.
Highlights • The current study is the first report referring to onlay bone augmentation using ReFit® with TB or PRP. • Both PRP and TB are equally effective for augmenting the bone with ReFit®. • We ...believe this study really contributes not only dental implant treatment but also bone reconstruction/regeneration after trauma, tumor resection and so on.
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