Enriched collagen solution as a pulp dressing in pulpotomized teeth in monkeys.

The purpose of this study was to assess the pulp healing process in baboon teeth after pulpotomy using an enriched collagen solution (ECS) as a pulp dressing. Twenty-five noncarious permanent teeth of two young baboon monkeys were pulpotomized under a rubber dam. After coronal pulp resection and hemostasis, ECS was applied on the pulp stumps and covered with sterile dental wax. The controls were covered with wax only. The cavities were sealed with IRM. The ECS was prepared from native, acid-soluble monkey skin collagen. The concentrations used were 0.25-0.3% solution in neutral 0.4M NaCl buffered with O.O05M tris. Two months after treatment the animals were sacrificed by perfusion with 10% formalin so!ution and the teeth prepared for histologic examination. The results indicated that 80% of the treated teeth had vital pulps, as compared to 20% of control teeth. In the ECS-treated pulps, dentin bridges were present in 73% of the teeth vs. 30% in the controls. In many of the ECS-treated pulps, cells were seen proliferating through the incomplete dentin bridge into the pulp chamber. More than half of the ECS-treated teeth showed no pulpal inflammation after two months. Although preventive measures have reduced the incidence of dental caries, ~ pulp involvement still remains a common clinical problem. In permanent teeth, pulp exposures usually are treated by conventional endodontic procedures. The formocresol pulpotomy is the treatment of choice for pulp exposure in vital primary teeth. 2-7 However, despite the widespread use of this procedure, its usefulness had been questioned; histological examination of dental pulps in dogs, ~ monkeys,9 and humans~° revealed inflammation, internal resorption, fibrosis, and necrosis of the residual radicular pulp following formocresol treatB. Sofer-Saks, MSc ment. Moreover, the mutagenic and carcinogenic potential of formocresol has been demonstrated.ll Thus, the need for a more biologically acceptable pulp dressing following pulpotomy in primary teeth became evident. Several investigators have tested glutaraldehyde and a diluted (4%) solution of formocresol. Although both materials appeared to be less deleterious to pulp tissue than the original Buckley’s formula, neither resulted in a normal histologic appearance of the residual pulp tissue. 12,13 Recently, complete pulpal healing has been achieved in the dog 30 days after pulpotomy using an enriched collagen solution (ECS) as a pulp dressing. 14 This article reports results obtained from further examination of the efficacy of ECS as a dressing agent using the baboon monkey as a test animal for a protracted period of time (two months). Methods and Materials The native ECS preparation was made as previously described, is Acid-soluble native collagen was extracted with cold 0.5M acetic acid from the skin of a young monkey and further purified using the trichloroaceticethanol method, lyophilized, and kept at -20°C in vacuo until used. Before use, a 0.4% collagen solution in 0.4M NaC1-001M tris, pH 7.6 was prepared, to which an equal volume of Medium 199 was added. All procedures were performed under sterile conditions. The experiments were carried out in 29 noncarious permanent teeth of two young baboon monkeys. Preoperative radiographs were taken to assess the state of root development and the absence of pulpal or periapical pathology. All the teeth had complete roots and closed apices. Treatments were done under sterPEDIATRIC DENTISTRY: December 1984Nol. 6 No. 4 243 TABLE. The Effect of ECS on Pulpotomized Teeth: Histologic Findings Number of Teeth Treated