Abstract
This study was designed to examine morphological changes of periodontally diseased root surfaces and determine the most effective root surface treatment for connective tissue reattachment and new cementum formation after flap operation.
Each of ten extracted human periodontally diseased teeth was split longitudinally into three pieces. The first group containing of ten root pieces was left untreated, the second was root-planed (RP) and the third was treated with (citric acid CA) following RP. The ultrastructure of the seroot surfaces was examined under transmission electron microscopy. The following results were obtained.
In untreated cementum, collagen fibers were frequently intact or whenever they were degraded, the change was limited to several micrometers in depth from the root surface. In the RP group, the number of specimens with cementum remaining was one -third of the total . In the CA group, the density of the denuded collagen fibers on the dentin surface was lower than that on the cementum surface, and the direction of denuded collagen fibers on cementum varied according to the surface structure. These findings show that collagen fibers of diseased root surfaces change a little morphologically and the almost intact collagen fibers lay bare on the CA treated root surfaces.
