The influence of storage conditions on the clonogenic capacity of periodontal ligament cells: implications for tooth replantation

Abstract

Viable periodontal ligament (PL) cells are required for PL healing of avulsed teeth following replantation. If immediate replantation cannot be accomplished, the ability of PL progenitor cells to reproduce (clonogenic capacity) and recolonize the wound may be extended by prevention of desiccation and storage in physiological media. This investigation examined the effects of storage in saliva, milk, Hank's balanced salt solution (HBSS) and Eagle's medium (alpha MEM) on the clonogenic capacity of human PL progenitor cells at 30 and 60 min extra-alveolar time. Twenty erupted human premolar teeth extracted as atraumatically as possible for orthodontic purposes were used in the present study. Fifteen premolars were placed immediately in freshly collected autologous saliva at room temperature, (+ 23 degrees C) for 15 min. These 15 premolars were next divided into three groups of five and stored in either saliva, milk or HBSS at + 4 degrees C in plastic cups surrounded by ice. The remaining five teeth served as positive controls and were immediately placed in alpha MEM at + 4 degrees C. PL tissue was scraped from one-half of the root surface with a scalpel at 30 and 60 min total extra-alveolar duration. Cells were released from the tissue sample with a 30 min enzymatic digestion procedure and the cells from the tissue samples analyzed for clonogenic capacity. There was a reduction in clonogenic capacity with time for all protocols. Periodontal ligament cells stored in alpha MEM showed the least reduction between 30 and 60 min and the greatest reduction was observed for PL cells stored in saliva. The difference in clonogenic capacity following transfer from saliva to milk or HBSS was not significant at 30 min. At 60 min, cells transferred from saliva to HBSS had a statistically higher percentage of clonogenic cells than those transferred to milk (5.9% vs. 3.5%; P < 0.05). We conclude that immediate storage of avulsed teeth in autologous saliva, followed by transfer to chilled milk, preserves the presence of sufficient progenitor cells in the PL to warrant replantation and the possibility of PL healing at 60 min extra-alveolar duration.

Tooth replantation: an update

“…As mentioned previously, vitality of periodontal ligament cell, affected by extraoral time and storage conditions, has greater effect on healing than splinting period or type [33].…”

Medios de almacenamiento y transporte para dientes avulsionados

“…Pero tanto el agua como la saliva alteran la estructura del fibroblasto, por lo que no son aconsejables como medio de transporte del diente, aunque son mejores que hacerlo en seco. 7,10,[12][13][14][15][16]18,20,21 • Suero fisiológico: Tiene una osmolalidad de 280 -285 mOsm/ Kg, un pH de 7,0 13,18 y es estéril, por lo que es un medio de conservación aceptable a corto plazo, manteniendo la vitalidad celular unas tres horas. 3,7,11,14,18,19,24,26 • Solución balanceada de HanK's (HBSS): Es un medio de cultivo estándar usado en la investigación biomédica para la conservación celular.…”

“…17 Sin embargo, sólo previene la muerte celular, pero no restituye la forma ni restablece la capacidad mitótica de las células. 2,21,25 Estudios recientes indican que a nivel celular el almacenamiento en leche es similar a la solución de Hank's, siempre que el período en seco no exceda de treinta minutos. Por tanto, la leche es un muy buen medio de almacenamiento a corto plazo, si se coloca el diente en ella como máximo media hora después del trauma.…”

“…3,12 Respecto a la temperatura de transporte, los estudios no son concordantes; pues unos aconsejan conservar en leche a temperatura ambiente (20°C) y otros proponen leche fría (4°C) para mantener l a c a p a c i d a d c l o n o g é n i c a celular. 3,19,21,22,27 Leche evaporada entera 6,1 313 1 25…”

Egg White-Milk Mixture as a Novel Biological Storage Media for Avulsed teeth Periodontal Ligament Cells: An In-Vitro Study

“…However, more than 15 min of dry storage, PDL stem cells are no longer able to differentiate into fibroblasts [11]. Furthermore, after 30 min all the remaining PDL and stem cells on the tooth root are likely to become necrotic [12,13]. Immediate replantation results in PDL healing up to 85% of mature teeth [14].…”