Osteogenic Activity of Odontoblasts in Transplanted Tooth Pulps

Abstract

SYNOPSIS IN INTERLINGUA ACTIVITATE OSTEOGENIC DE ODONTOBLASTOS IN TRANSPLANTATE PULPA DENTAL.-Intacte pulpa dental ab incisores de rattos adulte esseva transplantate subcutaneemente ad in animals homologe de un a quatro dies de etate con le objective de studiar le formation de tissu calcificate per le odontoblastos. Post le transplantation e le restauration de odontoblastos intacte, tanto spiculas de osso compacte como etiam osso spongiose de characteristicas simile a dentina esseva formate. Post 24 dies, le odontoblastos esseva circumferentiate de stratos de iste genere de osso. Odontoblastos que habeva previemente formate dentina comenciava producer osso quando illos esseva non plus in contacto con tissu oral. Formationes cellular simile a immatur structures dental esseva inducite per le odontoblastos in tissu fibrose de sito adjacente al transplantas.The ability of the osteoblast to form calcified tissue is not unique, and this capacity is shared with other mesenchymal cells under suitable conditions. The odontoblast is important in the formation of dentin, and its activity is similar to that of the osteoblast in intramembranous bone formation.1 After calcification of dentin, odontoblasts strongly resemble osteoblasts2 and, when grown in vitro, they are similar morphologically and cytochemically.3A 4Bone and dentin are closely related in both organic and inorganic composition,5 and information about odontoblasts can serve as another approach to the study of calcification.Dental transplants in a variety of sites have been observed to participate in the formation of hard tissues.5'-" These studies have been limited to tooth germs before calcification has begun. The tooth germ is a mixed organ of ectodermal and mesodermal derivatives with different nutritional requirements.noted. Adult odontoblasts that had been active in the formation of hard tissue were transplanted to animals to define further their role in the formation of calcified tissue and to make comparison with bone formation under other experimental conditions. Materials and MethodsThe incisors were removed from adult Sprague-Dawley strain rats, weighing 100 to 150 Gm., that had been killed by an overdose of ether. The surrounding bone was dissected away and the enamel organs, removed according to the technic of Reith,'2 were preserved for another study. The teeth were then split and the pulps removed. These were stored briefly in petri dishes containing phosphate-buffered saline solution with streptomycin and penicillin at 150 C.The pulps were transplanted to littermate Sprague-Dawley rats as follows: Group Ithree litters of 32 newborn rats; Group IItwo litters of 24 rats, 1 day old; Group IIIthree litters of 30 rats, 2 days old; Group IV-two litters of 28 rats, 3 days old, and Group V-two litters of 24 rats, 3 days old, thymectomized at birth.In each of the 138 rats, two transplants were made (a) in right and left groins, (b) in right and left neck regions, between the clavicle and mandible, or (c) in the groin and in the neck. The rats were anest...

Differences in the osteoinductive potential of transplanted isogeneic dental structures of the rat

“…Osseous tissue had formed following the transplantation of the pulpal tissue which is in accord with earlier similar studies [Zussman, 1966;Zerosi and Ossido, 1972]. The observation that such structures were found more often in the subcutaneous trans plantation site than in the brain substance may be related to the difficulties encountered in the intracerebral transplantation (see Material and methods).…”

“…The observation that such structures were found more often in the subcutaneous trans plantation site than in the brain substance may be related to the difficulties encountered in the intracerebral transplantation (see Material and methods). Transplanted pulp tissue and the structure developed as a result of the transplantation have both been found to become resorbed within a relatively short time [Zaleski et a i, 1966], As compared to earlier experiments of pulp transplantation [Zaleski et a i, 1966;Zussman, 1966], the observation periods in the present experiment were considerably longer, and consequently some of the transplants together with the tissues evoked by the transplantation may have been resorbed before the time of attemps to recovery.…”

“…Falconer, 1966], The way the pulp tissue was removed from the pulp chamber evidently left the major part of the odontoblasts on the pulp surface [Rockert, 1964;Hanson et a!., 1975]. Such odontoblasts have been found to become necrotic following allogeneic transplantation of the pulp [Zussman, 1966], possibly as a result of a disruption of the odontoblastic processes at removal of the cells from the pulpal wall. On the other hand, damage to the pulp possibly provokes embryonal po tencies in its tissue components [Waldhard and Linares, 1972] and thus a mesenchymal blastema would be available for a renewed dentinogenesis.…”

“…Because no such tissues came in contact with the transplanted pulp tissue in the present experi ment it would be against expectations to find any odontoblasts at recovery of the trans plants. The designation of cells developing from transplanted pulps as odontoblasts [Zussman, 1966] thus seems unfounded.…”

Capacity of Dental Pulp Differentiation in Mouse Molars as Demonstrated by Allogenic Tooth Transplantation

“…Other studies have shown that isolated pulp tissue contributes to bone tissue formation in transplants (Zussman 1966;Luostarinen and Ronning 1977;Yamamura 1985;Takei et al 1988;Inoue and Shimono 1992;Laino et al 2005). In contrast, the pulpal mesenchymal cells from postnatal mouse incisors can give rise to odontoblasts and osteoblasts and functionally produce matrix when transplanted into kidney capsules (Braut et al 2002(Braut et al ,2003.…”