Healing Of Periapical Tissues Research Articles

Histological study of periapical tissue healing in the rat molar after retrofilling with various materials

We histologically examined the effects on the periapical tissue of various dental filling materials applied as retrofillings in rats and compared them with those of amalgam. The 4-META-TBB resin Superbond and the light-cured composite resin produced the least severe inflammatory reaction, with the greatest amount of new bone. In these specimens, regeneration of a part of the periodontal ligament was also observed. These results indicate that these materials might be very biocompatible and thus foster the natural regeneration of the periapical tissue.

Irritating effect of formocresol after pulpectomy in vivo.

A study was carried out to investigate the effect of formocresol (formalin-creosote) on the periapical tissue after pulpectomy in rats. A pulpectomy was performed on the mesial root of the right mandibular first molar, and, in group A, a paper point containing saline was inserted into the root canal. In group B, a paper point containing formocresol was inserted, and in group C, a drop of formocresol was applied and a paper point containing formocresol was inserted into the root canal. The periapical tissue was examined histologically and histometrically at 3, 7, 14, and 28 days after insertion, and the inflammatory cells and fibroblasts in the apical granulation tissue were also counted. Histologically, in group A, the inflammation observed was slight at 14 and 28 days, while in groups B and C, a moderate inflammation remained. Histometrically, the area of the apical periodontal ligament in groups B and C was increased significantly compared with that in group A at 14 and 28 days. The inflammatory cell count in groups B and C increased significantly compared with that in group A at 7, 14, and 28 days, whereas the fibroblast count in Groups B and C decreased compared with that in Group A at 7, 14, and 28 days. These results demonstrate that formocresol delayed the healing of periapical tissue after pulpectomy.

Biologic properties of eugenol and zinc oxide-eugenol: A clinically oriented review

Eugenol-containing dental materials are frequently used in clinical dentistry. When zinc oxide-eugenol (ZOE) is applied to a dentinal cavity, small quantities of eugenol diffuse through the dentin to the pulp. Low concentrations of eugenol exert anti-inflammatory and local anesthetic effects on the dental pulp. Thus use of ZOE temporary filling may facilitate pulpal healing; on the other hand, high eugenol concentrations are cytotoxic. Direct application of eugenol to pulp tissue may result in extensive tissue damage. The ability of ZOE-based endodontic sealers to influence periapical tissue healing is considered in view of eugenol's anti-inflammatory and toxic properties.