Alveolar regeneration

BACKGROUND: Alveolar bone is a critical tissue for tooth retention; however, once alveolar bone is lost, it may not spontaneously regenerate. Currently, bone grafts or artificial bone are commonly used for alveolar bone regeneration therapy. However, these therapies require surgical procedures, which present risks, particularly in aged patients. Therefore, the development of alveolar bone regeneration techniques that do not require surgical procedures is critical. It is well known that stem cells present in the periosteal and periodontal ligament may be induced to differentiate into osteogenic cells...

PURPOSE: The primary aim of the study was to describe a novel technique to evaluate volumetric hard tissue dimensional changes after ridge augmentation procedures. The secondary aim was to apply this newly developed measuring method to compromised alveolar sockets grafted with a slowly resorbing biomaterial covered with a collagen membrane. MATERIALS AND METHODS: Eleven patients (6 men and 5 women, mean age 52.7 ± 8.3 years) requiring extraction of one hopeless tooth for severe periodontitis in the maxillary anterior area were consecutively treated with a ridge augmentation procedure...

Alveolar echinococcosis is a chronically progressive and potentially fatal disease. Patients with multiple giant alveolar echinococcosis have a poor prognosis when radical resection cannot be achieved, but curative resection can be limited by low future remnant liver volumes. In these cases, 2-stage liver resection may be a better choice: after a first-stage hepatectomy with partial resection, liver regeneration is allowed in the residual liver before proceeding to the second-stage hepatectomy. In this study, we therefore retrospectively reviewed and evaluated the safety and feasibility of two-stage hepatectomy in patients with multiple giant alveolar echinococcosis...

It is complicated to decide the treatment plan of hopeless anterior teeth in esthetic zone due to severe periodontitis, periodontal-endodontic combined lesion or teeth trauma. The optional treatment plan for this kind of teeth includes retention after periodontal treatment, extraction and implant treatment, extraction and prosthodontic treatment and so on. To make an appropriate treatment plan, patients' periodontal conditions, periodontal biotype, local anatomy, esthetic demand, economic condition and social psychological status should be comprehensively considered...

Bioengineered lungs consisting of a decellularized lung scaffold that is repopulated with a patient's own cells could provide desperately needed donor organs in the future. This approach has been tested in rats, and has been partially explored in porcine and human lungs. However, existing bioengineered lungs are fragile, in part because of their immature vascular structure. Herein, we report the application of adipose-derived stem/stromal cells (ASCs) for engineering the pulmonary vasculature in a decellularized rat lung scaffold...

The aim of this study was to examine the efficacy and safety of autogenous partially demineralized dentin matrix (APDDM) prepared onsite, for clinical application in bone regeneration procedures related to implant dentistry, including socket preservation, alveolar ridge augmentation, and maxillary sinus floor augmentation. In this study, 16 patients underwent dental implant placement using APDDM transplantation. There were no systemic or local complications (including surgical site infection) in any of the cases, and oral rehabilitation using dental implants was successful in all cases for at least 2 years after attachment of the suprastructure...

The human periodontium is a uniquely complex vital structure, supporting and anchoring the teeth in their alveolar sockets, playing thereby a decisive role in tooth homeostasis and function. Chronic periodontitis is a highly prevalent immune-inflammatory disease of the periodontium, affecting 15% of adult individuals and is characterized by progressive destruction of the periodontal tooth-investing tissues, culminating in their irreversible damage. Current periodontal evidence-based treatment strategies achieve periodontal healing via repair processes, mostly combating the inflammatory component of the disease, to halt or reduce prospective periodontal tissue loss...

The epithelial cells lining the mammalian lung are subjected to constant interaction with the external environment, necessitating robust regeneration strategies to deal with cell loss due to natural turn over or damage arising via inhaled agents or disease. Since lung epithelium function extends beyond respiratory gas exchange to include roles such as immune defense and mucocillary clearance, a diverse complement of epithelial cell types exists that are regionally distributed along the respiratory tree and extensive surface area of the alveolar interface...

Platelet-derived growth factor (PDGF)-A, which only signals through PDGF-receptor-alpha (PDGFRα) is required for secondary alveolar septal formation. Although PDGFRα distinguishes mesenchymal progenitor cells during the saccular stage, PDGFRα-expressing alveolar cells persist through adulthood. PDGF-A sustains proliferation, limits apoptosis, and maintains alpha-smooth muscle actin (αSMA) containing alveolar cells, which congregate at the alveolar entry ring at postnatal day (P)12. PDGFRα-expressing, αSMA-containing, alveolar cells re-distribute in the elongating septum, suggesting that they migrate to the alveolar entry rings where mechanical tension is higher...

For years, in order to improve bone regeneration and prevent the need of a second stage surgery to remove non-resorbable membranes, biological absorbable membranes have gradually been developed and applied in guided tissue regeneration (GTR). The present study's main objective was to achieve space maintenance and bone regeneration using a new freeze-dried developed porcine collagen membrane, and compare it with an already commercial collagen membrane, when both were used with a bovine xenograft in prepared alveolar ridge bone defects...

Cementum formation on the exposed tooth-root surface is a critical process in periodontal regeneration. Although various therapeutic approaches have been developed, regeneration of integrated and functional periodontal complexes is still wanting. Here, we found that the OCCM30 cementoblasts cultured on fibrin matrix express substantial levels of matrix proteinases, leading to the degradation of fibrin and the apoptosis of OCCM30 cells, which was reversed upon treatment with a proteinase inhibitor, ε-aminocaproic acid (ACA)...

function between the circulation and the atmospheric environment. Lung diseases, including lung cancer, are among the leading causes of death in the modern society. Research on lung development, regeneration and cancer could provide significant insights for the development of therapeutic approaches on lung diseases. Hippo/YAP/TAZ signaling pathway regulates cell proliferation and differentiation, controls organ size, and plays an important role in response to mechanical forces. YAP/TAZ are expressed in many cell types and serve various regulatory functions in the embryonic and adult lungs...

Cells, scaffolds, and growth factors play important roles in bone regeneration. Bone morphogenetic protein 9 (BMP9), a member of BMP family, could facilitate osteogenesis by regulating growth factors and promoting angiogenesis. Similar to other stem cells, rat dental follicle stem cells (rDFCs), the precursor cells of cementoblasts, osteoblasts and periodontal ligament cells, can self-renew and exhibit multipotential capacity. Coralline hydroxyapatite (CHA) has good biocompatibility and conductivity required for bone tissue engineering...

The canine mandible is useful for studying bone regeneration after dental implant placement. However, it is limited in investigations of peri-implant osteogenesis under osteoporotic conditions due to the insignificant osteoporotic effect of ovariectomy. This study aimed to establish a local osteoporotic model without ovariectomy using receptor activator of nuclear factor kappa-B ligand (RANKL) in a canine mandible model. This new model was used to evaluate the effects of injectable β-tricalcium phosphate microsphere bone grafts (TCP) on peri-implant bone regeneration under osteoporotic conditions with combinations of human recombinant bone morphogenetic protein-2 (rhBMP-2)...

After influenza infection, lineage-negative epithelial progenitors (LNEPs) exhibit a binary response to reconstitute epithelial barriers: activating a Notch-dependent ΔNp63/cytokeratin 5 (Krt5) remodelling program or differentiating into alveolar type II cells (AEC2s). Here we show that local lung hypoxia, through hypoxia-inducible factor (HIF1α), drives Notch signalling and Krt5(pos) basal-like cell expansion. Single-cell transcriptional profiling of human AEC2s from fibrotic lungs revealed a hypoxic subpopulation with activated Notch, suppressed surfactant protein C (SPC), and transdifferentiation toward a Krt5(pos) basal-like state...

BACKGROUND: The reconstruction of alveolar ridges for implant placement is still a challenging surgical procedure, especially in the case of extensive vertical and horizontal bone atrophy. OBJECTIVE: The objective of the present study was to evaluate the quantity and quality of newly regenerated bone; clinically by means of direct clinical measuring, ridges augmented by autogenous cortical bone associated with autogenous particulate bone graft in the posterior lower jaw defect...

Regenerative therapies of pathogenic tissue defects are gaining increasing importance in periodontology. Among others, the osteogenic effect of BMP-7 seems to play a major role in the development of teeth and alveolar bone. Human periodontal ligament stem cells (hPDLSC), as well as human mesenchymal stem cells (hMSC), show the ability to differentiate into various types of tissues. Regarding prostaglandin E2, many studies have confirmed that it is involved in the inflammation associated to periodontitis stimulating osteoclasts, which ultimately leads to resorption of tooth supporting bone...

The aim of this systematic review was to evaluate instrumentation procedures of the alveolar ridge expansion technique (ARST) with or without Guided Bone Regeneration (GBR) and to identify the most used instruments for successful outcome. An electronic as well as manual literature search was conducted in several databases including Medline, Embase, and Cochrane Central Register of Controlled Trials, for articles written in English up to September 2016. The question in focus was to identify the type of device for ridge expansion that is most frequently used and provides adequate bone expansion and implant success rate...

Trauma to the adjacent hard and soft tissue is the most common iatrogenic injury during extraction of the mandibular third molar. As every functional component of the dental arch is of prime importance in contemporary dental practice, the major concern must be in conserving the tooth and its structure as much as possible. The present case discusses the application of this conservative approach for management of iatrogenically damaged distal root of the mandibular second molar during extraction of impacted third molar, in which excessive guttering of alveolar bone and fractured apical third of distal root of 37 was observed radiographically...

BACKGROUND: The role of simvastatin in lowering serum cholesterol level is well described. However, recent findings suggest they have a role in bone formation as well. AIM AND OBJECTIVES: The present prospective study was conducted to evaluate the efficacy of simvastatin on bone formation in extraction sockets. MATERIALS AND METHODS: 15 patients undergoing all four first premolar extraction were selected based on inclusion and exclusion criteria...