5^th American Dental Congress

Biography

Biography: Miroslav Tolar

Abstract

Tissue bioengineering/regeneration is becoming a valid treatment modality in medicine and dentistry. It is making its way into oral and maxillofacial surgery, implantology, endodontics, orthodontics, prosthodontics. Patients like a regenerated own tissue that is maintained by its homeostatic mechanisms much more than artificial materials. It is clear that, at present, only adult mesenchymal stem cells (MSC) isolated from the patient and re-implanted to the same patient qualify for a clinical use. rnResearch into biology and physiology of MSC revealed a number of interesting, sometimes surprising, features, by which MSC communicate with other cells. In response to tissue damage, MSC can synthesize and release growth factors and chemoattractants of immune cells, both supporting tissue regeneration. MSC can respond to biophysical clues in their environment (like oxygen tension and pH). MSC can also sense and respond to attachment substrate’s elasticity variations and external mechanical forces. Of course, MSC can undergo their own tissue-specific differentiation process and become a source of regenerating cells. New findings show that MSC can form and release exosomes influencing behavior of neighboring cells when endocytosed. rnIn situ microenvironment of MSC needs to be replicated as much as possible after explantation in vitro, namely physiological tissue normoxia and three-dimensional structure of cultures. Platelet-rich plasma or fibrins are often beneficial for both multiplication and differentiation of MSC. rnRecently, a number of clinical studies reported successful uses of bioengineered implants, thus showing possible ways for further investigations. Large mandibular defects were healed by bioengineered bone implants. Alveolar clefts were filled by bioengineered implants, sometimes in combination with distraction osteogenesis or guided bone regeneration. Dental pulp regeneration bioengineering technique has entered a clinical trial. Other clinical applications of MSC include engineering of soft-tissue, PDL, cartilage and skeletal muscle. Neural crest-derived MSC may differentiate into neurons or glia and support healing of spinal cord injuries. Promising developments indicate that an engineered bioroot may be available in a not very far future.