Influence of cryopreservation on the pulpal tissue of immature third molars in vitro

Abstract

The purpose of this study was to evaluate in vitro the viability of isolated and non-isolated pulpal tissue of immature third molars after cryopreservation. This study was divided in three different experiments. Experiment 1: Pulpal tissue isolated from 19 third molars was divided in horizontal segments. Each segment was cultured separately in order to evaluate whether differences in growth capacity within the tissue could be found. Experiment 2: Pulpal tissue isolated from 27 third molars was divided in a mesial and a distal part. One part was cryopreserved before culturing, the other part was cultured immediately. Growth capacity of cryopreserved and non-cryopreserved tissue was evaluated and compared. Experiment 3: 43 third molars were cryopreserved. After thawing, the dimension of the apical foramen was measured and the pulp was isolated and segmented horizontally. The different parts were cultured and growth capacity was evaluated and compared. Results of experiment 1 and 2 showed no significant difference in growth capacity between fibroblasts originating from different pulpal segments of the same tooth without cryopreservation and between fibroblasts originating from cryopreserved and non-cryopreserved isolated pulpal tissue. In experiment 3 it was demonstrated that the dimension of the apical foramen and pulpal viability after cryopreservation are positively correlated. A minimum dimension of 9.42 mm(2) enables the cryoprotective agent to penetrate sufficiently and to protect the pulpal tissue from apex to crown. This study proved that cryopreservation of human pulpal tissue is possible if the cryoprotective agent can reach the entire pulp.

Human dental pulp stem cells derived from different cryopreservation methods of human dental pulp tissues of diseased teeth

“…Temmerman et al. (5) proved that cryopreservation of human pulp tissue would be possible if the cryoprotective agent could reach the entire pulp. Consequently, if a novel cryopreservation modality could be invented, as demonstrated by Lee et al.…”

“…Reviewing the English-language literature, to our knowledge, previous research into the cryopreservation of hDPSCs has chiefly focused on healthy permanent third molars and premolars (3)(4)(5)(6)(7). To our knowledge, there is a lack of detailed data focusing on the exploration of hDPSCs from the other types of tooth, Cryopreserved hDPSC from diseased vital teeth particularly for diseased but vital teeth.…”

“…Although there have been low rates of successful isolation of hDPSCs from intact teeth after cryopreservation, whole teeth have been successfully cryopreserved and thawed for the purpose of reimplantation (17,18). Temmerman et al (5) proved that cryopreservation of human pulp tissue would be possible if the cryoprotective agent could reach the entire pulp. Consequently, if a novel cryopreservation modality could be invented, as demonstrated by Lee et al (7), improvements in cryopreservation efficiency could be attained.…”

Influência de um protocolo de criopreservação no rendimento in vitro de células-tronco derivadas do tecido adiposo

“…Several studies have suggested different cryopreservation times, which vary from one day to longer periods 11,12 . The time used in the current article for our experiments corresponds to what we found in the literature, as several authors evaluated the cryopreservation effect after 30 days 9,13,14 without observing significant differences in proliferation and differentiation capacity between cryopreserved cells and non-cryopreserved cells.…”

Dental-Related Stem Cells and Their Potential in Regenerative Medicine

“…In the case of teeth or dental tissues cryopreservation, minimal processing may needed for banking. There are some evidences which are demonstrated the successful cryopreservation of healthy and diseased teeth as well as dental tissues [72][73][74][75][76][77][78]. On the other hand, cryopreservation of DSCs still has been considered as an active area of the researches.…”