Periodontal repair using PerioGlas in nonhuman primates: Clinical and histologic observations
The purpose of this study was to examine the clinical and histologic properties of PerioGlas when placed in surgically created intraosseous defects in a primate model. The researchers took six monkeys and established gingival health by mechanical and chemical oral-hygiene procedures. Four-millimeter osseous defects were created after raising full-thickness flaps. These defects were planed with burs and curettes to remove existing PDL and cementum. Most of the sites were two-walled; some were three-wall lingual or palatal. The animals each received PerioGlas, tricalcium phosphate (TP), and two hydroxyapatite implants (HA).There were also two sites in each animal that served as control. After the surgery the animals were given IM injections of Achromycin. Oral hygiene was performed three times a week for the remainder of the study.
Healing was uneventful and the monkeys maintained gingival health through the study. Some particle exfoliation was observed with the tricalcium phosphate and HA. This was not apparent with Perio Glas. After one month no new bone or cementum was seen in any of the specimens. There was minimal epithelial downgrowth in the PerioGlas specimens as compared to the considerable downgrowth in the other sites. Root resorption was a consistent finding in the PerioGlas sites; however, this did not appear to be aggressive and was self-limiting. No differences in material performance were seen when comparing four- to six-month specimens. Histologic measurements of PerioGlas in the four- to six-month specimens showed a 68% defect repair when measuring for new attachment. TP had 55% repair, HA 34%, and controls had 34%. Bone repair with PerioGlas was 47% of the original bone height, while TP was 31%, HA 18%, and control 21%. The results showed no difference between materials and particle size. PerioGlas demonstrated two clinically favorable characteristics. Ease of compactability and hemostasis were reported by the operators. The material packed well into defects, was strongly adherent, and appeared to harden as a solid after it was packed. These properties were different from HA and TP, which were frequently difficult to manage in hemorrhagic sites.
Within the limits of this study, the results suggest that intraosseous defects appear to be partially repaired with the use of PerioGlas. PerioGlas also appears to retard epithelial downgrowth, seems to have clinical properties that allow favorable packing and may have hemostatic properties in intraosseous defects. The size was not related to the healing response of all materials tested. [M.C.R.]
Fetner, A., M. Hartigan, and S. Low, Compendium, 7:932, 1994