Quantification of lactate-dehydrogenase and cell viability in postmortem human dental pulp.
Understanding pulp repair and regeneration requires being familiar with this tissue's behavior under extreme conditions, such as postmortem state where an abrupt interruption of tissue blood supply occurs. The purpose of this study was to quantify cell viability and the amount of lactate-dehydrogenase (LDH) expressed in human pulp tissue 6, 12, and 24 hours postmortem to establish how long dental pulp remains viable after death. Pulp samples were obtained from 14 unidentified corpses of people who had received lethal injuries in car accidents or from gunshot wounds; they had at least three caries- and restoration-free incisors. Half of each sample was used for determining cell viability at three different time intervals. The rest of each sample was used for quantifying LDH expression at the same time intervals. Another 14 pulp samples were obtained from live patients' healthy premolars where extraction was indicated for orthodontic reasons to assess normal LDH value in pulp tissue. The results showed cell viability decreasing from 89 to 68 to 41% measured 6, 12, and 24 hours postmortem, respectively. LDH expression in healthy pulps was 246 U/mg pulp weight. Expression increased after death from 249 U/mg at 6 hours to 337 U/mg at 12 hours. LDH expression decreased to 131 U/mg 24 hours postmortem. These findings are valuable in understanding dental pulp survival capability under extreme conditions that may have important clinical significance in terms of repair and regeneration.
Caviedes-Bucheli
Javier
J
Department of Graduate Studies, School of Dentistry, Pontificia Universidad Javeriana, Bogotá, Colombia. javiercaviedes@cable.net.co
Avendaño
Nuvia
N
Gutierrez
Rhina
R
Hernández
Sandra
S
Moreno
Gloria Cristina
GC
Romero
María Consuelo
MC
Muñoz
Hugo Roberto
HR
D000704:Analysis of Variance; D002470:Cell Survival; D003782:Dental Pulp / Q000166:cytology / Q000201:enzymology*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000096:biosynthesis; D011180:Postmortem Changes; D013997:Time Factors
D007770:L-Lactate Dehydrogenase