the continued erosion and replacement of bone tissue is called
bone remodeling
6524731
in the resorption process. High levels of calcium, magnesium, phosphate and products of collagen will be released into the extracellular fluid as the osteoclasts tunnel into the mineralized bone. Osteoclasts are prominent in the tissue destruction found in psoriatic arthritis and rheumatological disorders. The human body is in a constant state of bone remodeling. Bone remodelling is a process which maintains bone strength and ion homeostasis by replacing discrete parts of old bone with newly synthesized packets of proteinaceous matrix. Bone is resorbed by osteoclasts, and is deposited by osteoblasts in a process called ossification. Osteocyte activity plays a key
Bone resorption
11287880
osteoblasts. Together, the cells that are responsible for bone remodeling are known as the basic multicellular unit (BMU), and the temporal duration (i.e. lifespan) of the BMU is referred to as the bone remodeling period. Bone remodeling Bone remodeling (or bone metabolism) is a lifelong process where mature bone tissue is removed from the skeleton (a process called "bone resorption") and new bone tissue is formed (a process called "ossification" or "new bone formation"). These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity. Remodeling responds also to
Bone remodeling
11287877
Bone remodeling Bone remodeling (or bone metabolism) is a lifelong process where mature bone tissue is removed from the skeleton (a process called "bone resorption") and new bone tissue is formed (a process called "ossification" or "new bone formation"). These processes also control the reshaping or replacement of bone following injuries like fractures but also micro-damage, which occurs during normal activity. Remodeling responds also to functional demands of the mechanical loading. In the first year of life, almost 100% of the skeleton is replaced. In adults, remodeling proceeds at about 10% per year. An imbalance in the regulation of bone
Bone remodeling
4480283
Ossification Ossification (or osteogenesis) in bone remodeling is the process of laying down new bone material by cells called osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in the formation of normal, healthy bone tissue: Intramembranous ossification is the direct laying down of bone into the primitive connective tissue (mesenchyme), while endochondral ossification involves cartilage as a precursor. In fracture healing, endochondral osteogenesis is the most commonly occurring process, for example in fractures of long bones treated by plaster of Paris, whereas fractures treated by open reduction and internal fixation with metal plates, screws, pins,
Ossification
4480288
evolving as an osmotic barrier, or as a protective structure. Ossification Ossification (or osteogenesis) in bone remodeling is the process of laying down new bone material by cells called osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in the formation of normal, healthy bone tissue: Intramembranous ossification is the direct laying down of bone into the primitive connective tissue (mesenchyme), while endochondral ossification involves cartilage as a precursor. In fracture healing, endochondral osteogenesis is the most commonly occurring process, for example in fractures of long bones treated by plaster of Paris, whereas fractures treated by
Ossification
9574379
declines to zero approximately 6 months after injection. Bone remodeling is the process by which the body continuously removes old bone tissue and replaces it with new bone. It is driven by various types of cells, most notably osteoblasts (which secrete new bone) and osteoclasts (which break down bone); osteocytes are also present in bone, but their role is still not well understood. Precursors to osteoclasts, called pre-osteoclasts, express surface receptors called RANK (receptor activator of nuclear factor-kappa B). RANK is a member of the tumor necrosis factor receptor (TNFR) superfamily. RANK is activated by RANKL (the RANK-Ligand), which exists
Denosumab
19475095
constriction is called negative remodeling. Tissue remodeling occurs in adipose tissue with increased body fat. In obese subjects, this remodeling is often pathological, characterized by excessive inflammation and fibrosis. Tissue remodeling Tissue remodeling is the reorganization or renovation of existing tissues. Tissue remodeling can be either physiological or pathological. The process can either change the characteristics of a tissue such as in blood vessel remodeling, or result in the dynamic equilibrium of a tissue such as in bone remodeling. Macrophages repair wounds and remodel tissue by producing extracellular matrix and proteases to modify that specific matrix. A myocardial infarction induces
Tissue remodeling
6524731
in the resorption process. High levels of calcium, magnesium, phosphate and products of collagen will be released into the extracellular fluid as the osteoclasts tunnel into the mineralized bone. Osteoclasts are prominent in the tissue destruction found in psoriatic arthritis and rheumatological disorders. The human body is in a constant state of bone remodeling. Bone remodelling is a process which maintains bone strength and ion homeostasis by replacing discrete parts of old bone with newly synthesized packets of proteinaceous matrix. Bone is resorbed by osteoclasts, and is deposited by osteoblasts in a process called ossification. Osteocyte activity plays a key
Bone resorption
15347942
the bone will become less dense and weaker due to the lack of the stimulus required for continued remodeling. This reduction in bone density (osteopenia) is known as stress shielding and can occur as a result of a hip replacement (or other prosthesis). The normal stress on a bone is shielded from that bone by being placed on a prosthetic implant. The remodeling of bone in response to loading is achieved via mechanotransduction, a process through which forces or other mechanical signals are converted to biochemical signals in cellular signaling. Mechanotransduction leading to bone remodeling involve the steps of mechanocoupling,
Wolff's law
1801476
the granulation tissue develop into chondroblasts which also form hyaline cartilage. These two new tissues grow in size until they unite with each other. These processes culminate in a new mass of heterogeneous tissue known as a fracture callus. Callus formation peaks at day 14 of fracture. Eventually, the fracture gap is bridged. The next phase is the replacement of the hyaline cartilage and woven bone with lamellar bone. The replacement process is known as endochondral ossification with respect to the hyaline cartilage and bony substitution with respect to the woven bone. Substitution of woven bone happens before substitution of
Bone healing
48475
made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization of bone; osteoclasts are involved in the resorption of bone tissue. Modified (flattened) osteoblasts become the lining cells that form a protective layer on the bone surface. The mineralised matrix of bone tissue has an organic component of mainly collagen called "ossein" and an inorganic component of bone mineral made up of various salts. Bone tissue is a mineralized tissue of two types, cortical bone and cancellous bone. Other types of tissue found in bones include bone marrow, endosteum, periosteum, nerves, blood
Bone
6288756
lingual to the functional tooth in the incisors and postcanines. While a replacement canine does exist, more often than not it is not erupted and the original functional canine remains. The bone tissue of "Thrinaxodon" consists of fibro-lamellar bone, to a varying degree across all the separate limbs, most of which develops into parallel-fibred bone tissue towards the periphery. Each of the bones contains a large abundance of globular osteocyte lacunae which radiate a multitude of branched canaliculi. Ontogenetically early bones, of which are mostly fibro-lamellar tissue, possessed a large amount of vascular canals. These canals are oriented longitudinally within
Thrinaxodon
8255696
not replaced, but is allowed to heal and develop its own fibrous scar tissue so that the joint is no longer bone-to-bone, a pseudoarthrosis (also called a "false joint"). The neck of the femur is usually removed at the same time as the head. This prevents the post operative complication of bone rubbing on bone and continued pain. This has led to the procedure often also called "Femoral head and neck ostectomy". Animals who have had the operation are required to maintain a lower weight to compensate for the loss of skeletal integrity, and typically have excellent functional outcomes with
Femoral head ostectomy
13137845
Nonossifying fibroma A nonossifying fibroma (also called fibroxanthoma) is a common benign bone tumor in children and adolescents. However, it is controversial whether it represents a true neoplasm or rather a developmental disorder of growing bone. Radiographically, the tumor presents as a well marginated radiolucent lesion, with a distinct multilocular appearance. These foci consist of collagen rich connective tissue, fibroblasts, histiocytes and osteoclasts. They originate from the growth plate, and are located in adjacent parts of the metaphysis and diaphysis of long bones, most often of the legs. No treatment is needed in asymptomatic patients and spontaneous remission with replacement
Nonossifying fibroma
48496
immobile, then the joint is called a "suture". The formation of bone is called ossification. During the fetal stage of development this occurs by two processes: intramembranous ossification and endochondral ossification. Intramembranous ossification involves the formation of bone from connective tissue whereas endochondral ossification involves the formation of bone from cartilage. Intramembranous ossification mainly occurs during formation of the flat bones of the skull but also the mandible, maxilla, and clavicles; the bone is formed from connective tissue such as mesenchyme tissue rather than from cartilage. The process includes: the development of the ossification center, calcification, trabeculae formation and the
Bone
4621427
It is one of the myeloproliferative disorders, diseases of the bone marrow in which excess cells are produced at some stage. Production of cytokines such as fibroblast growth factor by the abnormal hematopoietic cell clone (particularly by megakaryocytes) leads to replacement of the hematopoietic tissue of the bone marrow by connective tissue via collagen fibrosis. The decrease in hematopoietic tissue impairs the patient's ability to generate new blood cells, resulting in progressive pancytopenia, a shortage of all blood cell types. However, the proliferation of fibroblasts and deposition of collagen is a secondary phenomenon, and the fibroblasts themselves are not part
Myelofibrosis
17739889
2001). He is a strong supporter of FC Porto. Reis began his research into biomaterials in 1990. He studies the development of biomaterials from natural origin polymers and their possible biomedical applications, including bone replacement and fixation, drug delivery carriers, partially degradable bone cements and tissue engineering scaffolding. His team works under his leadership in the tissue engineering of many different tissues, namely: bone, cartilage, osteochondral, skin, tendon and ligaments, meniscus, intervertebral disks, as well as on peripheral and central nervous systems regeneration, diabetes treatment and cancer 3D disease models. In 2015 Reis' research team developed a new type of
Rui L. Reis
48483
exclusively with red marrow or hematopoietic marrow, but as the child ages the hematopoietic fraction decreases in quantity and the fatty/ yellow fraction called marrow adipose tissue (MAT) increases in quantity. In adults, red marrow is mostly found in the bone marrow of the femur, the ribs, the vertebrae and pelvic bones. Bone is a metabolically active tissue composed of several types of cells. These cells include osteoblasts, which are involved in the creation and mineralization of bone tissue, osteocytes, and osteoclasts, which are involved in the reabsorption of bone tissue. Osteoblasts and osteocytes are derived from osteoprogenitor cells, but
Bone
8980111
Endosteum The endosteum (plural endostea) is a thin vascular membrane of connective tissue that lines the inner surface of the bony tissue that forms the medullary cavity of long bones. This endosteal surface is usually resorbed during long periods of malnutrition, resulting in less cortical thickness. The outer surface of a bone is lined by a thin layer of connective tissue that is very similar in morphology and function to endosteum. It is called the periosteum, or the periosteal surface. During bone growth, the width of the bone increases as osteoblasts lay new bone tissue at the periosteum. To prevent
Endosteum
8312595
Epiphyseal plate The epiphyseal plate (or epiphysial plate, physis, or growth plate) is a hyaline cartilage plate in the metaphysis at each end of a long bone. It is the part of a long bone where new bone growth takes place; that is, the whole bone is alive, with maintenance remodeling throughout its existing bone tissue, but the growth plate is the place where the long bone grows longer (adds length). The plate is not only found in children and adolescents; in adults, who have stopped growing, the plate is replaced by an epiphyseal line. This replacement is known as
Epiphyseal plate
14311558
Bone mineral Bone mineral (also called inorganic bone phase, bone salt, or bone apatite) is the inorganic component of bone tissue. It gives bones their compressive strength. Bone mineral is formed from carbonated hydroxyapatite with lower crystallinity. Bone mineral is formed from globular and plate structures distributed among the collagen fibrils of bone and forming yet a larger structure. The bone salt and collagen fibers together constitute the extracellular matrix of bone tissue. Often the plural form "bone salts" is used; it reflects the notion of various salts that, on the level of molecular metabolism, can go into the formation
Bone mineral
14311560
problems with those glands (such as hypo- or hyperparathyroidism or hypo- or hyperthyroidism) can create problems with bone mineral density (as well as hypo- or hypercalcemia). Bone mineral Bone mineral (also called inorganic bone phase, bone salt, or bone apatite) is the inorganic component of bone tissue. It gives bones their compressive strength. Bone mineral is formed from carbonated hydroxyapatite with lower crystallinity. Bone mineral is formed from globular and plate structures distributed among the collagen fibrils of bone and forming yet a larger structure. The bone salt and collagen fibers together constitute the extracellular matrix of bone tissue. Often
Bone mineral
4319636
interconnect. This becomes the canaliculi of osteons. Since bone spicules tend to form around blood vessels, the perivascular space is greatly reduced as the bone continues to grow. When replacement to compact bone occurs, this blood vessel becomes the central canal of the osteon. Intramembranous ossification Intramembranous ossification is one of the two essential processes during fetal development of the gnathostome (excluding chondrichthyans such as sharks) skeletal system by which rudimentary bone tissue is created. Intramembranous ossification is also an essential process during the natural healing of bone fractures and the rudimentary formation of bones of the head. Unlike endochondral
Intramembranous ossification
48513
can either destroy bone (called a "lytic" cancer) or create bone (a "sclerotic" cancer). Cancers of the bone marrow inside the bone can also affect bone tissue, examples including leukemia and multiple myeloma. Bone may also be affected by cancers in other parts of the body. Cancers in other parts of the body may release parathyroid hormone or parathyroid hormone-related peptide. This increases bone reabsorption, and can lead to bone fractures. Bone tissue that is destroyed or altered as a result of cancers is distorted, weakened, and more prone to fracture. This may lead to compression of the spinal cord,
Bone
138616
skull. This is a special form of cast and mold formation. If the chemistry is right, the organism (or fragment of organism) can act as a nucleus for the precipitation of minerals such as siderite, resulting in a nodule forming around it. If this happens rapidly before significant decay to the organic tissue, very fine three-dimensional morphological detail can be preserved. Nodules from the Carboniferous Mazon Creek fossil beds of Illinois, USA, are among the best documented examples of such mineralization. Replacement occurs when the shell, bone or other tissue is replaced with another mineral. In some cases mineral replacement
Fossil
14051301
Magnetic Resonance Imaging, is considered the imaging study of choice in identifying Tarlov cysts. MRI provides better resolution of tissue density, absence of bone interference, multiplanar capabilities, and is noninvasive. Plain films may show bony erosion of the spinal canal or of the sacral foramina On MRI pictures, the signal is the same as the CSF one. If MRI made with a contrast medium: A computed tomography (CT) scan is another examination method often used for the diagnosis of Tarlov cyst. Unenhanced CT scans may show sacral erosion, asymmetric epidural fat distribution, and cystic masses that have the same density
Tarlov cyst
8980112
the bone from becoming unnecessarily thick, osteoclasts resorb the bone from the endosteal side. Endosteum The endosteum (plural endostea) is a thin vascular membrane of connective tissue that lines the inner surface of the bony tissue that forms the medullary cavity of long bones. This endosteal surface is usually resorbed during long periods of malnutrition, resulting in less cortical thickness. The outer surface of a bone is lined by a thin layer of connective tissue that is very similar in morphology and function to endosteum. It is called the periosteum, or the periosteal surface. During bone growth, the width of
Endosteum
5224219
increasingly used to make bone grafting materials as well as dental prosthetics and repair. Some implants, e.g. hip replacements, dental implants and bone conduction implants, are coated with HA.. As the native dissolution rate of hydroxyapatite in-vivo, around 10 wt% per year, is significantly lower than the growth rate of newly formed bone tissue, in its use as a bone replacement material, ways are being sought to enhance its solubility rate and thus promote better bioactivity. Microcrystalline hydroxyapatite (MH) is marketed as a "bone-building" supplement with superior absorption in comparison to calcium. It is a second-generation calcium supplement derived from
Hydroxyapatite
4319633
consisting of mineralized osteoid that contains osteocytes and is lined by active osteoblasts. The nidus, that began as a diffuse collection of MSCs, has become rudimentary bone tissue. The first step in the process is the formation of bone spicules which eventually fuse with each other and become trabeculae. The periosteum is formed and bone growth continues at the surface of trabeculae. Much like spicules, the increasing growth of trabeculae result in interconnection and this network is called woven bone. Eventually, woven bone is replaced by lamellar bone. Embryologic mesenchymal cells (MSC) condense into layers of vascularized primitive connective tissue.
Intramembranous ossification
8022146
cover the recession (called a pedicle graft) or use of a free graft of gingival or connective tissue from the roof of the mouth (called a "free gingival graft" or a Subepithelial connective tissue graft). Alternatively, a material called acellular dermal matrix (processed donated human skin allograft) may be used instead of tissue from the patient's own palate. Recent advances have seen the introduction of platelet derived growth factor (PDGF) infused bone graft material. This material is usually combined with the cellular matrix to form a soft bone paste that is then covered by the allograft. The development of this
Gingival recession
20723972
to achieve close fixation with the bone and will decrease patient recovery time considerably. Essentially, the foam becomes an extracellular matrix in the body as tissue is integrated into it. Today, the implants most commonly used for bone replacement lack the ability to promote these characteristics, which are found in natural bone and, as a result, the implants have limited lifetimes. This phenomenon of osseointegration works similarly to direct fracture healing. However, instead of a bone fragment-end reconnecting to bone, the fragment-end connects to an implant surface. In a study on fibroblastic interactions with high porosity Ti6Al4V, the metal foam
Titanium foam
6126977
Reticular connective tissue Reticular connective tissue is a type of connective tissue with a network of reticular fibers, made of type III collagen ("reticulum" = net or network). Reticular fibers are not unique to reticular connective tissue, but only in this type are they dominant. Reticular fibers are synthesized by special fibroblasts called reticular cells. The fibers are thin branching structures. Reticular connective tissue is found around the kidney, the spleen, and lymph nodes, Peyer's patches as well as in bone marrow. The fibers form a soft skeleton (stroma) to support the lymphoid organs (lymph node stromal cells, red bone
Reticular connective tissue
5453611
growth factors which activate receptors close to primary afferent neurons. Activation of these neural receptors is a contributing factor to pain sensation. Additionally, inflammatory lipids called prostaglandins, which are produced at high rates by cancer cells within tumors, activate nociceptors when they bind together. Stimulation of specialized pain-sensitive nerve fibers (nociceptors) that innervate bone tissue leads to the sensation of bone pain. Bone pain originates from both the periosteum and the bone marrow which relay nociceptive signals to the brain creating the sensation of pain. Bone tissue is innervated by both myelinated (A beta and A delta fiber) and unmyelinated
Bone pain
775195
is commonly called an alveolus, or "socket". Lying over the bone is the gingiva or gum, which is readily visible in the mouth. The periodontal ligament is a specialized connective tissue that attaches the cementum of a tooth to the alveolar bone. This tissue covers the root of the tooth within the bone. Each ligament has a width of 0.15–0.38mm, but this size decreases over time. The functions of the periodontal ligaments include attachment of the tooth to the bone, support for the tooth, formation and resorption of bone during tooth movement, sensation, and eruption. The cells of the periodontal
Human tooth
18743803
called a neural arch. The body is composed of cancellous bone, which is the spongy type of osseous tissue, whose micro-anatomy has been specifically studied within the pedicle bones. This cancellous bone is in turn, covered by a thin coating of cortical bone (or compact bone), the hard and dense type of osseous tissue. The vertebral arch and processes have thicker coverings of cortical bone. The upper and lower surfaces of the body of the vertebra are flattened and rough in order to give attachment to the intervertebral discs. These surfaces are the vertebral endplates which are in direct contact
Vertebra
102668
rex" leg bone from the Hell Creek Formation in Montana. After recovery, the tissue was rehydrated by the science team. When the fossilized bone was treated over several weeks to remove mineral content from the fossilized bone-marrow cavity (a process called demineralization), Schweitzer found evidence of intact structures such as blood vessels, bone matrix, and connective tissue (bone fibers). Scrutiny under the microscope further revealed that the putative dinosaur soft tissue had retained fine structures (microstructures) even at the cellular level. The exact nature and composition of this material, and the implications of Schweitzer's discovery, are not yet clear. In
Dinosaur
12487639
person who suffered severe infection, septic shock, underwent dialysis and ultimately paralysis due to having received an implant made from infected cadaver tissue from Mastromarino's company. Although a recent judicial ruling has increased the difficulty of patients in proving pain and suffering from receiving bad donor tissue in cases like these, Pfaff’s lawsuit is still pending. Other patients who received BTS-derived tissue and body parts include a Colorado woman who had to repeat her ACL replacement surgery after her first BTS tendon failed, an Ohio woman who developed syphilis after receiving a bone from BTS, and an Ohio man who
Biomedical Tissue Services
3880038
times a day. Another problem lack of mobility can cause is loss of bone density and changes in bone structure. Loss of bone density (bone demineralization), thought to be due to lack of input from weakened or paralysed muscles, can increase the risk of fractures. Conversely, a poorly understood phenomenon is the overgrowth of bone tissue in soft tissue areas, called heterotopic ossification. It occurs below the level of injury, possibly as a result of inflammation, and happens to a clinically significant extent in 27% of people. People with SCI are at especially high risk for respiratory and cardiovascular problems,
Spinal cord injury
8395299
(glass-like) table. These bones are composed of two thin layers of compact bone enclosing between them a variable quantity of cancellous bone, which is the location of red bone marrow. In an adult, most red blood cells are formed in flat bones. The intervening cancellous tissue is called the diploë, and this, in the nasal region of the skull, becomes absorbed so as to leave spaces filled with air–the paranasal sinuses between the two tables. Ossification is started by the formation of layers of undifferentiated connective tissue that hold the area where the flat bone is to come. On a
Flat bone
11170004
ultimate goals of tissue engineering is the creation of organs, such as the kidney, from basic constituents. A scaffolding is necessary to grow the entity into a functioning organ, after which the polymer scaffold would degrade and be safely eliminated from the body. There are reports of using polyglycolic acid and polylactic acid to engineer vascular tissue for heart repair. The scaffold can be used to help create undamaged arteries and vessels. In addition to tissue engineering, biodegradable polymers are being used orthopedic applications, such as bone and joint replacement. A wide variety of non-biodegradable polymers have been used for
Biodegradable polymer
8230301
enzyme inadequacy and glycoprotein accumulated. "Cleidocranial dysostosis" is a general skeletal condition named for the collarbone (cleido-) and cranium deformities which people with it often have. Common features include: "Fibrous dysplasia" causes bone thinning and growths or lesions in one or more bones of the human body. These lesions are tumor-like growths that consist of replacement of the medullary bone with fibrous tissue, causing the expansion and weakening of the areas of bone involved. Especially when involving the skull or facial bones, the lesions can cause externally visible deformities. The skull is often, but not necessarily, affected, and any other
Osteochondrodysplasia
2069770
developments in the multidisciplinary field of tissue engineering have yielded a novel set of tissue replacement parts and implementation strategies. Scientific advances in biomaterials, stem cells, growth and differentiation factors, and biomimetic environments have created unique opportunities to fabricate tissues in the laboratory from combinations of engineered extracellular matrices ("scaffolds"), cells, and biologically active molecules. Among the major challenges now facing tissue engineering is the need for more complex functionality, as well as both functional and biomechanical stability and vascularization in laboratory-grown tissues destined for transplantation. The continued success of tissue engineering, and the eventual development of true human replacement
Tissue engineering
2087278
or "tables") of cortical bone tissue between which is the cancellous bone tissue known in the cranial bones as diploë. The bone is especially thick at the ridges, protuberances, condyles, and anterior part of the basilar part; in the inferior cerebellar fossae it is thin, semitransparent, and without diploë. Near the middle of the outer surface of the squamous part of the occipital (the largest part) there is a prominence – the external occipital protuberance. The highest point of this is called the inion. From the inion, along the midline of the squamous part until the foramen magnum, runs a
Occipital bone
2489567
damage. This is called elastic deformation. Forces that exceed the capacity of bone to behave elastically may cause failure, typically bone fractures. Bone is a dynamic tissue that is constantly being reshaped by osteoblasts, which produce and secrete matrix proteins and transport mineral into the matrix, and osteoclasts, which break down the tissues. Osteoblasts are the major cellular component of bone. Osteoblasts arise from mesenchymal stem cells (MSC). MSC give rise to osteoblasts, adipocytes, and myocytes among other cell types. Osteoblast quantity is understood to be inversely proportional to that of marrow adipocytes which comprise marrow adipose tissue (MAT). Osteoblasts
Osteoblast
19111982
are lightweight yet strong and hard, and serve multiple functions. Mineralized osseous tissue or bone tissue, is of two types – cortical and cancellous and gives it rigidity and a coral-like three-dimensional internal structure. Other types of tissue found in bones include marrow, endosteum, periosteum, nerves, blood vessels and cartilage. Bone is an active tissue composed of different cells. Osteoblasts are involved in the creation and mineralisation of bone; osteocytes and osteoclasts are involved in the reabsorption of bone tissue. The mineralised matrix of bone tissue has an organic component mainly of collagen and an inorganic component of bone mineral
Hard tissue
9060903
the tissue linking the structures is ligamentous. A gomphosis is a specialized fibrous joint in which a conical process or peg of one bone fits into a hole or socket in another bone. (gomphos is a Greek word meaning bolt). Small quantity of fibrous tissue holds the bones together. No movement is possible at such peg-and-socket joints. Fibrous joint Fibrous joints are connected by dense connective tissue, consisting mainly of collagen. These are fixed joints where bones are united by a layer of white fibrous tissue of varying thickness. In the skull the joints between the bones are called sutures.
Fibrous joint
6008469
the different bioavailabilities of the different calcium salts. It can be used as a tissue replacement for repairing bony defects when autogenous bone graft is not feasible or possible. It may be used alone or in combination with a biodegradable, resorbable polymer such as polyglycolic acid. It may also be combined with autologous materials for a bone graft. Porous beta-Tricalcium phosphate scaffolds are employed as drug carrier systems for local drug delivery in bone. Tricalcium phosphate Tricalcium phosphate (sometimes abbreviated TCP) is a calcium salt of phosphoric acid with the chemical formula Ca(PO). It is also known as tribasic calcium
Tricalcium phosphate
7557726
to mature ultimately to megakaryocytes which cells shed membrane-enclosed fragments of their cytoplasm, i.e. platelets, into the blood. GATA1-inactivating mutations may thereby result in reduced levels of and/or dysfunctional blood platelets. Reduced levels of GATA1 due to defective translation of GATA1 mRNA in human megakaryocytes is associated with myelofibrosis, i.e. the replacement of bone marrow cells by fibrous tissue. Based primarily on mouse and isolated human cell studies, this myelofibrosis is thought to result from the accumulation of platelet precursor cells in the bone marrow and their release of excessive amounts of cytokines that stimulate bone marrow stromal cells to
GATA1
788327
would open an investigation of Macchiarini's work and publications. Several bioengineering approaches have been tested to repair and replace the trachea, indicating extraordinary difficulties in a successful graft due. A 2016 article cited the tremendous difficulties of tracheal revascularization as a major challenge to any form of tracheal replacement. The study also notes that on top of the revascularization issue, there is no evidence that using bone-marrow stem-cells on a de-cellularized native trachea or synthetic scaffold will induce airway tissue regeneration, and such a method remains hypothetical. Ligaments Trachea The trachea, colloquially called the windpipe, is a cartilaginous tube that
Trachea
4931396
storage which gives bone tissue its strength. In mature compact bone most of the individual lamellae form concentric rings around larger longitudinal canals (approx. 50 µm in diameter) within the bone tissue. These canals are called haversian canals. Haversian canals are contained within osteons, which are typically arranged along the long axis of the bone in parallel to the surface. The canals and the surrounding lamellae (8-15) form the functional unit, called a haversian system or osteon. Haversian canal Haversian canals (sometimes canals of Havers, named after British physician Clopton Havers) are a series of microscopic tubes in the outermost
Haversian canal
11580415
Guided bone and tissue regeneration Guided bone regeneration or GBR, and guided tissue regeneration or GTR are dental surgical procedures that use barrier membranes to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics or prosthetic restoration. GBR is similar to guided tissue regeneration (GTR) but is focused on development of hard tissues in addition to the soft tissues of the periodontal attachment. At present, guided bone regeneration is predominantly applied in the oral cavity to support new hard tissue growth on an alveolar ridge
Guided bone and tissue regeneration
11580423
in the aesthetic zone in terms of facial bone thickness. There are several uses of bone regeneration: Guided bone and tissue regeneration Guided bone regeneration or GBR, and guided tissue regeneration or GTR are dental surgical procedures that use barrier membranes to direct the growth of new bone and gingival tissue at sites with insufficient volumes or dimensions of bone or gingiva for proper function, esthetics or prosthetic restoration. GBR is similar to guided tissue regeneration (GTR) but is focused on development of hard tissues in addition to the soft tissues of the periodontal attachment. At present, guided bone regeneration
Guided bone and tissue regeneration
2489568
are found in large numbers in the periosteum, the thin connective tissue layer on the outside surface of bones, and in the endosteum. Normally, almost all of the bone matrix, in the air breathing vertebrates, is mineralized by the osteoblasts. Before the organic matrix is mineralized, it is called the osteoid. Osteoblasts buried in the matrix are called osteocytes. During bone formation, the surface layer of osteoblasts consists of cuboidal cells, called "active osteoblasts". When the bone-forming unit is not actively synthesizing bone, the surface osteoblasts are flattened and are called "inactive osteoblasts". Osteocytes remain alive and are connected by
Osteoblast
48474
Bone A bone is a rigid organ that constitutes part of the vertebrate skeleton. Bones support and protect the various organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, and enable mobility. Bones come in a variety of shapes and sizes and have a complex internal and external structure. They are lightweight yet strong and hard, and serve multiple functions. Bone tissue (osseous tissue) is a hard tissue, a type of dense connective tissue. It has a honeycomb-like matrix internally, which helps to give the bone rigidity. Bone tissue is
Bone
10432203
out in appearance. This destruction occurs as a result of the effect of bacterial endotoxins on bone tissue. Because the bone is alive, it contains cells in it that build bone, known as osteoblasts, and cells that break down bone, called osteoclasts. Usually these work at the same speed and keep each other in balance. In periodontitis, however, the chemical mediators, or by-products, of chronic inflammation stimulate the osteoclasts, causing them to work more rapidly than the cells that build bone. The net result is that bone is lost, and the loss of bone and attachment tissues is called periodontal
Scaling and root planing
4319158
Endochondral ossification Endochondral ossification is one of the two essential processes during fetal development of the mammalian skeletal system by which bone tissue is created. Unlike intramembranous ossification, which is the other process by which bone tissue is created, cartilage is present during endochondral ossification. Endochondral ossification is also an essential process during the rudimentary formation of long bones, the growth of the length of long bones, and the natural healing of bone fractures. The cartilage model will grow in length by continuous cell division of chondrocytes, which is accompanied by further secretion of extracellular matrix. This is called interstitial
Endochondral ossification
6489232
Myeloid tissue Myeloid tissue, in the bone marrow sense of the word "myeloid" ("myelo-" + "-oid"), is tissue of bone marrow, of bone marrow cell lineage, or resembling bone marrow, and myelogenous tissue ("myelo-" + "-genous") is any tissue of, or arising from, bone marrow; in these senses the terms are usually used synonymously, as for example with chronic myeloid/myelogenous leukemia. In hematopoiesis, myeloid or myelogenous cells are blood cells that arise from a progenitor cell for granulocytes, monocytes, erythrocytes, or platelets (the common myeloid progenitor, that is, CMP or CFU-GEMM), or in a narrower sense also often used, specifically
Myeloid tissue
3383952
periosteum. Additionally, the outer shell of the long bone is compact bone, then a deeper layer of cancellous bone (spongy bone) which contains in the medullary cavity the bone marrow. The outer shell of the long bone is made of cortical bone also known as compact bone. This is covered by a membrane of connective tissue called the periosteum. Beneath the cortical bone layer is a layer of spongy cancellous bone. Inside this is the medullary cavity which has an inner core of bone marrow, it contains nutrients and help in formation of cells, made up of yellow marrow in
Long bone
11286101
problem is particularly common, giving soft, white, 'corky' tissue. Spongy tissue is also a type of animal tissue which contains smooth muscles, fibrous tissues, spaces, veins, and arteries. An example is the corpus spongiosum penis. In bone, the spongy tissue is called cancellous tissue. Spongy tissue Spongy tissue is a type of tissue found both in plants and animals. In plants, it is part of the mesophyll, where it forms a layer next to the palisade cells in the leaf. The spongy mesophyll's function is to allow for the interchange of gases (CO2) that are needed for photosynthesis. The spongy
Spongy tissue
4621423
Myelofibrosis Primary myelofibrosis is a relatively rare bone marrow cancer. It is currently classified as a myeloproliferative neoplasm, in which the proliferation of an abnormal clone of hematopoietic stem cells in the bone marrow and other sites results in fibrosis, or the replacement of the marrow with scar tissue. The term "myelofibrosis" alone usually refers to primary myelofibrosis (PMF), also known as chronic idiopathic myelofibrosis (cIMF); the terms idiopathic and primary mean that in these cases the disease is of unknown or spontaneous origin. This is in contrast with myelofibrosis that develops secondary to polycythemia vera or essential thrombocythaemia. Myelofibrosis
Myelofibrosis
5453055
glasses from different laboratories and institutions around the world. The first successful surgical use of Bioglass 45S5 was in replacement of ossicles in middle ear as a treatment of conductive hearing loss, and the material continues to be used in bone reconstruction applications today. Bioactive glass offers good osteoconductivity and bioactivity, it can deliver cells and is biodegradable. This makes it an excellent candidate to be used in tissue engineering applications. Although this material is known to be brittle, it is still used extensively to enhance the growth of bone since new forms of bioactive glasses are based on borate
Bioglass
12167933
bone formation, or decreased risk of osteoporosis or other bone disorders in post-menopausal women." Femarelle has been tested in small clinical trials. One studied its effect on the tissue lining the vagina, another on relief of hot flashes in menopause, and another on the risk of causing blood clots, which is a risk of hormone replacement therapy. While results were promising, the studies were too small and too short in duration from which to draw conclusions. Femarelle Femarelle is a dietary supplement that is a mixture of DT56a (a tofu extract) and flaxseed powder, that may act as a selective
Femarelle
13130384
Nano-scaffold Nano-scaffolding (or nanoscaffolding) is a medical process used to regrow tissue and bone, including limbs and organs. The nano-scaffold is a three-dimensional structure composed of polymer fibers very small that are scaled from a Nanometer (10 m) scale. Developed by the American military, the medical technology uses a microscopic apparatus made of fine polymer fibers called a scaffold. Damaged cells grip to the scaffold and begin to rebuild missing bone and tissue through tiny holes in the scaffold. As tissue grows, the scaffold is absorbed into the body and disappears completely. Nano-scaffolding has also been used to regrow burned
Nano-scaffold
14407539
Primary bone Primary bone is the first bone tissue that appears in embryonic development and in fracture repair. It is characterized by its random position of collagen fibers. In most places in adults this tissue is replaced by secondary bone tissue except, for example, near the sutures of calvara or tooth sockets. The secondary bones have lower amounts of osteocytes so primary bone is much more easily penetrated by x-ray. Primary bone or the primary ossification center is the beginning of the bone building process during the first trimester. Calcificed cartilage is basophilic and new bone being made is more
Primary bone
13137846
by bone tissue is to be expected. Multiple nonossifying fibromas occur in Jaffe-Campanacci syndrome in combination with cafe-au-lait spots, mental retardation, hypogonadism, ocular and cardiovascular abnormalities. Nonossifying fibroma A nonossifying fibroma (also called fibroxanthoma) is a common benign bone tumor in children and adolescents. However, it is controversial whether it represents a true neoplasm or rather a developmental disorder of growing bone. Radiographically, the tumor presents as a well marginated radiolucent lesion, with a distinct multilocular appearance. These foci consist of collagen rich connective tissue, fibroblasts, histiocytes and osteoclasts. They originate from the growth plate, and are located in adjacent
Nonossifying fibroma
8170830
Bone density Bone density, or bone mineral density (BMD), is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to optical density per square centimetre of bone surface upon imaging. Bone density measurement is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk. It is measured by a procedure called densitometry, often performed in the radiology or nuclear medicine departments of hospitals or clinics. The measurement is painless and non-invasive and
Bone density
16669890
nucleus replacement devices, and artificial discs, through the retractor. Robot-assisted surgery is another technique that is used occasionally in minimally invasive spine surgery. When the procedure is done the tube is removed, and the wound is stitched, stapled, or glued shut. There are many spinal procedures that make use of minimally invasive techniques. They can involve cutting away tissue (discectomy), fixing adjacent vertebrae to one another (spinal fusion), and replacing bone or other tissue. The name of the procedure often includes the region of the spine that is operated on, including cervical spine, thoracic spine, lumbar spine. These procedures include:
Minimally invasive spine surgery
4621438
for Herbert Assmann, who published a description under the term "osteosclerosis" in 1907. It was characterised as a myeloproliferative condition in 1951 by William Dameshek. The Leukemia and Lymphoma Society describes myelofibrosis as a rare type of blood cancer, manifesting as a type of chronic leukemia. Myelofibrosis Primary myelofibrosis is a relatively rare bone marrow cancer. It is currently classified as a myeloproliferative neoplasm, in which the proliferation of an abnormal clone of hematopoietic stem cells in the bone marrow and other sites results in fibrosis, or the replacement of the marrow with scar tissue. The term "myelofibrosis" alone usually
Myelofibrosis
1678677
head, processes, and the thickened parts of the bone contain cancellous tissue; the rest consists of a thin layer of compact tissue. The central part of the supraspinatus fossa and the upper part of the infraspinatous fossa, but especially the former, are usually so thin in humans as to be semitransparent; occasionally the bone is found wanting in this situation, and the adjacent muscles are separated only by fibrous tissue. The scapula has two surfaces, three borders, three angles, and three processes. The front of the scapula (also known as the costal or ventral surface) has a broad concavity called
Scapula
19111989
of the pulp canal. Hard tissue Hard tissue (also termed calcified tissue) is tissue which is mineralized and has a firm intercellular matrix. The hard tissues of humans are bone, tooth enamel, dentin, and cementum. The term is in contrast to soft tissue. Bone is a rigid organ that constitutes part of the vertebral skeleton. Bones support and protect the various organs of the body, produce red and white blood cells, store minerals and also enable mobility. Bone tissue is a type of dense connective tissue. Bones come in a variety of shapes and sizes and have a complex internal
Hard tissue
19111981
Hard tissue Hard tissue (also termed calcified tissue) is tissue which is mineralized and has a firm intercellular matrix. The hard tissues of humans are bone, tooth enamel, dentin, and cementum. The term is in contrast to soft tissue. Bone is a rigid organ that constitutes part of the vertebral skeleton. Bones support and protect the various organs of the body, produce red and white blood cells, store minerals and also enable mobility. Bone tissue is a type of dense connective tissue. Bones come in a variety of shapes and sizes and have a complex internal and external structure. They
Hard tissue
15465287
only onto the material but also into its pores, and in some cases interconnecting within the material’s structure, in a process called "osseoincorporation". In some cases, the patient has periodontal defects (damaged or poor bone structure) which hinder osseointegration. Guided tissue and/or bone regeneration may be necessary before the bone can osseointegrate with the dental implant. In this case a combination of barrier membranes, bone tacks, and supplemental autogenous bone may be required to promote proper osseointegration. In addition, implant surface modification has been studied and now integrated, thus promoting an optimal tissue-implant interface (i.e. osseointegration, implant-gingival seal) Osseoincorporation Osseoincorporation
Osseoincorporation
3112085
also known as burned-out Paget's disease. A later phase of the disease is characterized by the replacement of normal bone marrow with highly vascular fibrous tissue. Sir James Paget first suggested the disease was due to an inflammatory process. Some evidence suggests that a paramyxovirus infection is the underlying cause of Paget's disease, which may support the possible role of inflammation in the pathogenesis. However, no infectious virus has yet been isolated as a causative agent, and other evidence suggests an intrinsic hyperresponsive reaction to vitamin D and RANK ligand is the cause. Further research is therefore necessary. The first
Paget's disease of bone
48480
and functional unit of cortical bone is the osteon. Cancellous bone, also called trabecular or spongy bone, is the internal tissue of the skeletal bone and is an open cell porous network. Cancellous bone has a higher surface-area-to-volume ratio than cortical bone because it is less dense. This makes it weaker and more flexible. The greater surface area also makes it suitable for metabolic activities such as the exchange of calcium ions. Cancellous bone is typically found at the ends of long bones, near joints and in the interior of vertebrae. Cancellous bone is highly vascular and often contains red
Bone
48478
as osteoblasts and osteoclasts. Within any single bone, the tissue is woven into two main patterns, known cortical and cancellous bone, and each with different appearance and characteristics. The hard outer layer of bones is composed of cortical bone also called compact bone being much denser than cancellous bone. It forms the hard exterior (cortex) of bones. The cortical bone gives bone its smooth, white, and solid appearance, and accounts for 80% of the total bone mass of an adult human skeleton. It facilitates bone's main functions: to support the whole body, protect organs, provide levers for movement, and store
Bone
11855446
because less bone is removed. Also, a quicker operation and shorter recovery period may be a result of less bone being removed during the operation and the soft tissue may sustain less trauma. Also, the rehabilitation process may be more progressive. More specific benefits of UKA are that it may improve range of motion, reduce blood loss during surgery, reduce the person’s time spent in the hospital, and decrease costs. In 2018, two of the most significant benefits of UKA or partial knee replacements are: 1. Partial knee replacement subjects report that their replaced knee feels more like their original
Unicompartmental knee arthroplasty
16730738
Healey has received awards from the Japanese Orthopaedic Association, and Peking University. Throughout his career, he has held various leadership positions in the Association of Bone and Joint Surgeons (past President, 2010-2011), and the Musculoskeletal Transplant Foundation. Healey has written more than 250 research articles and book chapters on the topics of osteosarcoma; Ewing sarcoma; Paget’s disease; soft tissue sarcomas; giant cell tumor of bone; joint replacement techniques in the surgical treatment of bone tumors; and the use of musculoskeletal surgery to improve pain and function in patients with advanced cancers. He has served as Deputy Editor of "Clinical Orthopaedics
John H. Healey
9483306
tissue consisting of fibrous tissue, fibrocartilage or hyaline-like cartilage. The quality of the repair tissue after these "bone marrow stimulating techniques" depends on various factors including the species and age of the individual, the size and localization of the articular cartilage defect, the surgical technique, e.g., how the subchondral bone plate is treated, and the postoperative rehabilitation protocol. The surgery was developed in the late 1980s and early 1990s by Dr. Richard Steadman of the Steadman-Hawkins clinic in Vail, Colorado. Steadman slowly refined the procedure through research (including tests on horses). The surgery was soon called "controversial" by many sportswriters,
Microfracture surgery
14087541
Mitochondrial replacement therapy Mitochondrial replacement therapy (MRT, sometimes called mitochondrial donation) is the replacement of mitochondria in one or more cells to prevent or ameliorate disease. MRT originated as a special form of in vitro fertilisation in which some or all of the future baby's mitochondrial DNA comes from a third party. This technique is used in cases when mothers carry genes for mitochondrial diseases. The therapy is approved for use in the United Kingdom. A second application is to use autologous mitochondria to replace mitochondria in damaged tissue to restore the tissue to a functional state. This has been
Mitochondrial replacement therapy
3039553
Bisphosphonate Bisphosphonates are a class of drugs that prevent the loss of bone density, used to treat osteoporosis and similar diseases. They are the most commonly prescribed drugs used to treat osteoporosis. They are called bisphosphonates because they have two phosphonate () groups. They are thus also called diphosphonates ("bis-" or "di-" + "phosphonate"). Evidence shows that they reduce the risk of fracture in post-menopausal women with osteoporosis. Bone tissue undergoes constant remodeling and is kept in balance (homeostasis) by osteoblasts creating bone and osteoclasts destroying bone. Bisphosphonates inhibit the digestion of bone by encouraging osteoclasts to undergo apoptosis, or
Bisphosphonate
19333327
components have different x-ray attenuating properties. The standard in bone mineral density scanning developed in the 1980s is called Dual X-ray Absorptiometry, known as DXA. The DXA technique uses two different x-ray energy levels to estimate bone density. DXA scans assume a constant relationship between the amounts of lean soft tissue and adipose tissue. This assumption leads to measurement errors, with an impact on accuracy as well as precision. To reduce soft-tissue errors in DXA, DXL technology was developed in the late 1990s by a team of Swedish researchers led by Prof. Ragnar Kullenberg. With DXL technology, the region of
Dual X-ray absorptiometry and laser
2489589
Osteoid In histology, osteoid is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the osteoid as several specific proteins. When the osteoid becomes mineralized, it and the adjacent bone cells have developed into new bone tissue. Osteoid makes up about fifty percent of bone volume and forty percent of bone weight. It is composed of fibers and ground substance. The predominant fiber-type is Type I collagen and comprises ninety percent of the osteoid. The ground substance is mostly made up of
Osteoid
2489591
to as growth spurts). Osteoid In histology, osteoid is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the osteoid as several specific proteins. When the osteoid becomes mineralized, it and the adjacent bone cells have developed into new bone tissue. Osteoid makes up about fifty percent of bone volume and forty percent of bone weight. It is composed of fibers and ground substance. The predominant fiber-type is Type I collagen and comprises ninety percent of the osteoid. The ground substance is
Osteoid
3112084
The osteolysis is followed by a compensatory increase in bone formation induced by the bone forming cells, called osteoblasts, that are recruited to the area. This is associated with accelerated deposition of lamellar bone in a disorganized fashion. This intense cellular activity produces a chaotic picture of trabecular bone ("mosaic" pattern), rather than the normal linear lamellar pattern. The resorbed bone is replaced and the marrow spaces are filled by an excess of fibrous connective tissue with a marked increase in blood vessels, causing the bone to become hypervascular. The bone hypercellularity may then diminish, leaving a dense "pagetic bone",
Paget's disease of bone
8866002
tissue there is a homeostasis between bone resorption and bone apposition. Diseased or damaged bone is resorbed through the osteoclasts mediated process while osteoblasts form new bone to replace it, thus maintaining healthy bone density. This process is commonly called remodelling. However, osteoporosis is essentially the result of a lack of new bone formation in combination with bone resorption in reactive hyperemia, related to various causes and contributing factors, and bisphosphonates do not address these factors at all. In 2011, a proposal incorporating both the reduced bone turnover and the infectious elements of previous theories has been put forward. It
Osteonecrosis of the jaw
2991701
Petrifaction In geology, petrifaction or petrification is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals. Petrified wood typifies this process, but all organisms, from bacteria to vertebrates, can become petrified (although harder, more durable matter such as bone, beaks, and shells survive the process better than softer remains such as muscle tissue, feathers, or skin). Petrifaction takes place through a combination of two similar processes: permineralization and replacement. These processes create replicas of the original specimen that are similar down to the
Petrifaction
3833601
article in "PNAS", "Human embryonic stem cells have the potential to differentiate into various cell types, and, thus, may be useful as a source of cells for transplantation or tissue engineering." However, embryonic stem cells are not limited to cell/tissue engineering. Current research focuses on differentiating ESCs into a variety of cell types for eventual use as cell replacement therapies (CRTs). Some of the cell types that have or are currently being developed include cardiomyocytes (CM), neurons, hepatocytes, bone marrow cells, islet cells and endothelial cells. However, the derivation of such cell types from ESCs is not without obstacles, therefore
Embryonic stem cell
2041781
of donor hair, and the quality and thickness of the scar tissue. Areas of significant scarring and/or tissue atrophy, which is likely to make hair grafting unsuccessful, are best excised and replaced by normal expanded scalp skin. Theoretically, there is no limit to the amount of tissue that can be created with tissue expansion, provided the process is conducted gradually. Bone is another tissue that can be expanded relatively easily, by using external devices which are slowly separated using mechanical contraptions, so that bone grows in response to elongation (bone distractor). Other techniques and external devices have been studied and
Tissue expansion
2803443
side. Removing just a small wedge of bone can "swing" the knee open, pressing the healthy tissue together as space opens up between the femur and tibia on the damaged side so that the arthritic surfaces do not rub against each other. Osteotomy is also used as an alternative treatment to total knee replacement in younger and active patients. Because prosthetic knees may wear out over time, an osteotomy procedure can enable younger, active osteoarthritis patients to continue using the healthy portion of their knee. The procedure can delay the need for a total knee replacement for up to ten
Osteotomy
6524730
Bone resorption Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood. The osteoclasts are multi-nucleated cells that contain numerous mitochondria and lysosomes. These are the cells responsible for the resorption of bone. Osteoclasts are generally present on the outer layer of bone, just beneath the periosteum. Attachment of the osteoclast to the osteon begins the process. The osteoclast then induces an infolding of its cell membrane and secretes collagenase and other enzymes important
Bone resorption
2849453
episodes of painful swelling of the masses and pain that ended spontaneously within 3 days. Pelvic radiography showed multiple soft-tissue masses and some bone erosion. Other traits included mild facial changes, acquired short stature as seen in other MPS disorders, and normal joint movement and intelligence. Currently there is no cure for these disorders. Medical care is directed at treating systemic conditions and improving the person's quality of life. Physical therapy and daily exercise may delay joint problems and improve the ability to move. Changes to the diet will not prevent disease progression, but limiting milk, sugar, and dairy products
Mucopolysaccharidosis
7016535
noun use of feminine of διπλόος ("diplóos", “double”) Diploë Diploë ( or ) is the spongy cancellous bone separating the inner and outer layers of the cortical bone of the skull. In the cranial bones, the layers of compact cortical tissue are familiarly known as the tables of the skull; the outer one is thick and tough; the inner is thin, dense, and brittle, and hence is termed the "vitreous table". The intervening cancellous tissue is called the diploë. In certain regions of the skull this becomes absorbed so as to leave spaces filled with liquid between the two tables.
Diploë
4593462
Avascular necrosis Avascular necrosis (AVN), also called osteonecrosis or bone infarction, is death of bone tissue due to interruption of the blood supply. Early on there may be no symptoms. Gradually joint pain may develop which may limit the ability to move. Complications may include collapse of the bone or nearby joint surface. Risk factors include bone fractures, joint dislocations, alcoholism, and the use of high-dose steroids. The condition may also occur without any clear reason. The most commonly affected bone is the femur. Other relatively common sites include the upper arm bone, knee, shoulder, and ankle. Diagnosis is typically
Avascular necrosis
7016534
Diploë Diploë ( or ) is the spongy cancellous bone separating the inner and outer layers of the cortical bone of the skull. In the cranial bones, the layers of compact cortical tissue are familiarly known as the tables of the skull; the outer one is thick and tough; the inner is thin, dense, and brittle, and hence is termed the "vitreous table". The intervening cancellous tissue is called the diploë. In certain regions of the skull this becomes absorbed so as to leave spaces filled with liquid between the two tables. From Ancient Greek διπλόη ("diplóē", “literally, a fold”),
Diploë
7371448
These bioactive materials should ideally be osteoinductive, osteoconductive, and osseointegratable. Bone substitute materials intended to replace autologous or allogeneic bone consist of bioactive ceramics, bioactive glasses, and biological and synthetic polymers. The basis of bone tissue engineering is that the materials will be resorbed and replaced over time by the body’s own newly regenerated biological tissue. Tissue engineering is not only limited to the bone: a large amount of research is devoted to cartilage, ligament, skeletal muscle, skin, blood vessel, and neural tissue engineering as well. Successful delivery of therapeutics to the intended target largely depends on the choice of
Nanofiber
16120801
adherent to other structures within the middle ear. Some retractions continue to progress and grow more deeply into the ear. This can result in erosion of bone. As the middle ear is only a narrow space, the eardrum only has to retract a short distance before it touches boney structures within the middle ear such as the ossicles. It may become adherent to these bones and in some cases, this contact leads to erosion of the bone. As well as ossicular erosion, the bone of the ear canal (e.g. the scutum) and even bone over the cochlea (the promontory) can
Tympanic membrane retraction
10579970
the touch. Diffuse PVNS symptoms are often confused with those of rheumatoid arthritis. While pigmented villonodular synovitis can occur in both pediatric and geriatric patients, it is more common with ages 20–50. PVNS is locally aggressive and can spread to surrounding tissues, causing bone erosion and tissue damage. If not treated early, it can spread to areas outside the joint, and potentially cause permanent loss of range as well as intense pain. The disorder also has, on average, a 45% rate of recurrence. The exact cause is unknown. Some doctors believe it is caused by abnormal metabolism of fat. Others
Pigmented villonodular synovitis
4010642
excellent long-term durability when properly placed and are still widely used in slightly modified versions. Early implant designs had the potential to loosen from their attachment to the bones, typically becoming painful ten to twelve years after placement. In addition, erosion of the bone around the implant was seen on x-rays. Initially, surgeons believed this was caused by an abnormal reaction to the cement holding the implant in place. That belief prompted a search for an alternative method to attach the implants. The Austin Moore device had a small hole in the stem into which bone graft was placed before
Hip replacement
19148521
only with rheumatic fever, it has since been shown to occur also in SLE, Sjögren syndrome, scleroderma, dermatomyositis, psoriatic arthritis, vasculitis, ankylosing spondylitis, mixed connective tissue disease, and pyrophosphate deposition disease. It is distinct from bone erosion which is commonly associated with rheumatic arthritis, and also distinct from mild deforming arthropathy which is associated with SLE. There have also been cases of non-rheumatic JA associated with Lyme disease, HIV-infection and a number of other conditions. Treatment focuses toward alleviating pain and in maintaining functionality of the affected joints through use of nonsteroidal anti-inflammatory drugs, corticosteroids, antimalarial drugs and physiotherapy. Surgery
Jaccoud arthropathy
14471530
ultraviolet light, and then degrade predictably over time. Such materials could be used to for orthopedic repairs, functioning as a replacement for damaged areas of bone and then slowly being replaced by regrowth of natural material as the body heals. Her pioneering approach applies photopolymerization and photodegradation to enable precise control in space and time of hydrogels' structure and composition. This research involves fundamental investigations into the molecular dynamics of processes at the cell-biomaterial interface. Anseth is also working on the tissue engineering of biomaterials for the replacement of cartilage and heart valves. By combining photopolymers and lab-grown cartilage her
Kristi Anseth
48487
large multinucleate cells that are responsible for the breakdown of bones by the process of bone resorption. New bone is then formed by the osteoblasts. Bone is constantly remodelled by the resorption of osteoclasts and created by osteoblasts. Osteoclasts are large cells with multiple nuclei located on bone surfaces in what are called "Howship's lacunae" (or "resorption pits"). These lacunae are the result of surrounding bone tissue that has been reabsorbed. Because the osteoclasts are derived from a monocyte stem-cell lineage, they are equipped with phagocytic-like mechanisms similar to circulating macrophages. Osteoclasts mature and/or migrate to discrete bone surfaces. Upon
Bone