Regenerative Endodontics

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Regenerative Endodontics "A Review of Current Status and A Call for Action."

Text of Regenerative Endodontics

  • 1.Dr. Sarjeev Singh Yadav Professor & Head. Dept of conservative Dentistry & Endodontics. Presented by: GOVERNMENT DENTAL COLLEGE & HOSPITAL HYDERABAD. 08/13/13 1YES YES WHY

2. Regenerative EndodonticsRegenerative Endodontics A Review of Current StatusA Review of Current Status and A Call for Actionand A Call for Action 08/13/13 2YES YES WHY 3. Each year approx $400 billion is spent treating Americans suffering some type of tissues loss. This includes 20000 organ transplants, 5,00000 joint replacement, and millions of dental and oral craniofacial procedures, ranging from tooth restorations to major reconstruction of facial soft and mineralized tissues. INTRODUCTION 08/13/13 3YES YES WHY 4. I. The regeneration or replacement of oral tissues affected by inherited disorders, trauma, and neoplastic or infectious diseases is expected to solve many dental problems with in next 25 years. II. As well as ability to stimulate endodontic regeneration III. Replace diseased tissue IV. Vaccinations against virus V. Genetically altered diseased pathogens to help eradicate caries and periodontitis VI. Patient demand for tissue engineering therapy. NEED FOR DEMAND 08/13/13 4YES YES WHY 5. Regenerative endodontic procedures can be defined as biologically based procedures designed to replace damaged structures, including dentin and root structures, as well as cells of the pulp-dentin complex. Definition of tissue engineering LANGER & VACANTI stated that it was an interdisciplinary field that applies the principle of engineering and life sciences towards the development of biological substitutes that restore, maintain, or improve tissue function. Langer & vacanti tissue engineering, science 1993:260.920-6 08/13/13 5YES YES WHY 6. The objectives of regenerative endodontic procedure, are to Regenerate pulp like tissue, ideally. The pulp -dentin complex Regenerate damaged coronal dentin, such as following a caries exposure Regenerate resorbed root, cervical or apical dentin. OBJECTIVE 08/13/13 6YES YES WHY 7. The counterargument to the development of regenerative endodontic procedures is In terms of esthetics. there is a potential risk that endodontic filling materials and sealers may discolor the tooth crown. van der Burgt TP. Plasschaert AJ .Tooth discoloration induced be dental materials. Oral Surg Oral Med Oral Pathol 1995b, 666-9 In addition, an in vitro studies of endodontically treated human teeth found the long-terns intracanal placement of calcium hydroxide may reduce the fracture resistance of root dentin. Doyon GE. Dumsha T, von Fraunhofer jA. Fracture resistance of human root dentin exposed to intracanal calcium hydroxide J Endod 2005.31-895-708/13/13 7YES YES WHY 8. A retrospective study of tooth survival times following root canal filling versus tooth restoration found that although root canal therapy prolonged tooth survival, the removal of pulp in a compromised tooth may still lead to tooth loss in comparison with teeth with normal tissues Caplan DJ, cai J, yin G, While BA Root canal filled versus non-root canal filled teeth, a retrospective comparison of survival times J Public Health Dent 2005;65; 9o-6 08/13/13 8YES YES WHY 9. 08/13/13 9YES YES WHY 10. Stem Cell 08/13/13 10YES YES WHY 11. What Is a Stem Cell? Unspecialized cells Give rise to more than 250 specialized cells in the body Serve as the bodys repair system Renew itself Replenish other cells 08/13/13 11YES YES WHY 12. A stem cell is commonly defined as a cell that has the ability to continuously divide and produce progeny cells that differentiate (develop) into various other types of cells or tissues The plasticity of the stem cell defines its ability to produce cells of different tissues 08/13/13 12YES YES WHY 13. What Are the Sources of Mature Stem Cells? Mature Body Tissues 08/13/13 13YES YES WHY 14. What Is a Treatment Example? 08/13/13 14YES YES WHY 15. Umbilical Cord & Placenta SC Research Isolated immediately following birth Whartons Jelly showing promise as a source More flexibility = some pluripotent characteristics Research is limited but growing 08/13/13 15YES YES WHY 16. What Are the Sources of Early Stem Cells? Somatic Cell Nuclear Transfer (SCNT) 08/13/13 16YES YES WHY 17. Where Are Early Stem Cells Found? 5 days of development Who did it first? In 1998, U. Wisconsin research team isolates stem cells from IVF-blastocysts 08/13/13 17YES YES WHY 18. How Big Is a Blastocyst? 08/13/13 18YES YES WHY 19. What Are the Characteristics? Early stem cells are pluripotent Retain the special ability to develop into nearly any cell type 08/13/13 19YES YES WHY 20. How Would SCNT Treat Disease? 08/13/13 20YES YES WHY 21. In Summary: Two Major Types of SC Mature Stem Cells Early Stem Cells Adult (includes umbilical cord & placenta) Embryonic; blastocystic Cells obtained from specific mature body tissues, umbilical cord, placenta Cells obtained from inner cell mass of a blastocyst Multipotent Give rise to multiple but limited cell types Pluripotent Flexible, give rise to any cell type in the body 08/13/13 21YES YES WHY 22. Both Kinds of SCR are Needed Mature Stem Cells Early Stem Cells First isolated in 1960s First isolated in 1998 50+ years of research 9+ years of research Federal Funding = >$2.7 Billion (FY02-06) Federal Funding = $132 Million (FY02-06) Results: 50+ human therapies Results: Only in animal trials; No human trials 08/13/13 22YES YES WHY 23. Preserve This Ban This 08/13/13 23YES YES WHY 24. However, the sourcing of embryonic stem cells is controversial and is surrounded by ethical and legal issues, which reduces the attractiveness of these cells for developing new therapies. This explains why many researchers are now focusing attention on developing stem cell therapies using postnatal stem cells donated by the patients themselves or their close relatives. 08/13/13 24YES YES WHY 25. The application of postnatal stem cell therapy was launched in 1968, when the first allogenic bone marrow transplant was successfully used in the treatment of severe combined immunodeficiency Kenny AB, Hitzig WH. Bone marrow transplantation for severe combined immunodeficiency disease. Reported from 1968 to 1977. Eur J Pediatr 1979;131:15577. 08/13/13 25YES YES WHY 26. Since the 1970s, bone marrow transplants have been used to successfully treat leukemia, lymphoma, various anemias, and genetic Disorders Postnatal stem cells have been sourced from umbilical cord blood, umbilical cord, bone marrow, peripheral blood, body fat, and almost all body tissues including the pulp tissue of teeth Tsukamoto Y, Fukutani S, Shin-Ike T, et al. Mineralized nodule formation by cultures of human dental pulp-derived fibroblasts. Arch Oral Biol 1992;37:104555. 08/13/13 26YES YES WHY 27. One of the first stem cell researchers was Dr. John Enders, who received the 1954 Nobel Prize in medicine for growing polio virus in human embryonic kidney cells In 1998, Dr. James Thomson, isolated cells from the inner cell mass of the early embryo and developed the first human embryonic stem cell lines In 1998, Dr. John Gearhart derived human embryonic germ cells from cells in fetal gonadal tissue (primordial germ cells) 08/13/13 27YES YES WHY 28. There is increased interest in autogenous postnatal stem cells as an alternative source for clinical applications, because these cells are readily available and have no immunogenicity issues, even though they may have reduced plasticity. Stem cells are often categorized by their source: The most practical clinical application of a stem cell therapy would be to use a patients own donor cells. Autologous stem cells are obtained from the same individual to whom they will be implanted. 08/13/13 28YES YES WHY 29. Stem cells could be taken from the bone marrow peripheral blood fat removed by liposuction the periodontal ligament oral mucosa, or skin. An example of an autologous cell bank is one that stores umbilical cord stem cells It may be possible to use neuronal stem cells from adipose fat as part of regenerative medicine instead of bone marrow cells, possibly providing a less painful and less threatening alternative collection method. Seo BM, Miura M, Sonoyama W, Coppe C, Stanyon R, Shi S. Recovery of stem cells from cryopreserved periodontal ligament. J Dent Res 2005;84:90712. 08/13/13 29YES YES WHY 30. concern applies to very ill or elderly persons. One potential disadvantage of harvesting cells from patients is that surgical operations might lead to postoperative sequelae, such as donor site infection To accomplish endodontic regeneration, the most promising cells are autologous postnatal stem cells, because these appear to have the fewest disadvantages that would prevent them from being used clinically Nakashima M, Iohara K, Ishikawa M, et al. Stimulation of reparative dentin formation by ex vivo gene therapy using dental pulp stem cells electrotransfected with growth/differentiation factor 11 (Gdf11). Hum Gene Ther 2004;15:104553.08/13/13 30YES YES WHY 31. Allogenic cells originate from a donor of the same species Examples of donor allogenic cells include blood cells used for a Blood transfusion Bone marrow cells used for a bone marrow transplant Donated egg cells used for in vitro transplantation However, the most serious disadvantages of using preexisting cell lines from donors to treat patients are the risks of immune rejection and pathogen transmission 08/13/13 31YES YES WHY 32. The use of donated allogenic cells, such as dermal fibroblasts from human foreskin, has been demonstrated to be immunologically safe and thus a viable choice for tissue engineering of skin for burn victims The FDA has approved several companies producing skin for burn victims using donated dermal fibroblasts The same technology may be applied to replace pulp tissues after root canal therapy, but it has not yet been evaluated and published. Slifkin M, Doron S, Snydman DR. Viral pro