Long-term cryopreservation of dental stem cells

Cryopreservation is a procedure of a long-term storage of cells and/or tissues at a temperature that prevents cell divisions and metabolic processes. Due to ability to self-renewal and differentiation into more specialised cells, stem cells may be helpful in repairing of other damaged organs or tissues. Cryopreservation allows the frozen genetic material to maintain its biological properties for a long time. Therefore, there is a real chance for some samples to be used in the future therapy of the pathological conditions that at present remain incurable because of the current state of knowledge. The purpose of this review is to describe the modern methods of extraction, preservation, and storage of dental stem cells at low temperatures in particular procedure of collecting and transporting tissues intended for freezing, precise characteristics of stem cells of dentary origin and methods of their isolation using Enzymatic Digestion and Spontaneous Outgrowth. In the paper are also presented technical details of the protocols of rapid rate freezing, controlled rate milling and freezing in a magnetic field (magnetic freezing) which provides precise information about procedures of thawing cells and unfavourable effect of negative temperature on the biological properties of stem cells. Dental tissues may constitute a rich source of stem cells. The inexpensive, simple and quick procedure of their extraction is minimally invasive and does not pose a threat to the donor's organism. Transferring autologous cells within the same organism does not present a potential risk of transplant rejection and thereof does not raise ethical controversies. Laboratory procedures including cell preparation, its characteristics and genetic features, basics on the process of freezing, thawing, as well as quality control essentials have been also outlined.

Application of stem cells in dentistry for bone regeneration

Stem cells constitute a non-specialised cell pool able for proliferation, self-renewal and differentiation into progeny constantly replacing used up tissue and/or organ fragments. They have been observed to be present in many tissue reservoirs, including stomatognathic system. Oral cavity seems to be a particularly attractive stem cells' source as these cells are richly present and easily accessible in dental and periodontal tissues and they can be used for therapeutic purposes. Their application is also morally and ethically non-controversial. Bone tissue structure restoration together with restoring its weight-bearing and nutritive function depend on the proper function of stem cells supported with other techniques including tissue engineering. Traditionally, bone regeneration means bone restoration supported by newly formed bones supplied by stem cells of tissue reservoir. It may be also indispensable to create a scaffold which may support the bone formation facilitating the transportation of cells and cell stimulating molecules involving both the matrix and bone-forming cells. The regenerative potential of stem cells present in oral cavity can be used, for instance, to restore maxillary and mandibular bones. The bones support natural teeth or prostheses and regress as soon as at least the one tooth is lost or extracted. Bone mass loss makes it difficult to conduct effective dental treatment and reduces the chances of obtaining positive, long-lasting therapeutic effects. It seems that modern and innovative therapies based on stem cells application may bring spectacular effects especially in patients in whom routine medical activities did not lead to satisfactory results.