[Effect of self-made colloid paste on gingival retraction in dogs]

To evaluate the efficiency of self-made paste on gingival retraction in dogs as well as its potential clinical application.Forty teeth from two mature dogs were prepared with 0.5 mm wide shoulder in the lip and buccal sides of the teeth, and then divided into four groups randomly. The gingival grooves of the four groups were filled with self-made colloid paste, Expasyl gingival retraction paste, gingival retraction cord, and medicated (15.5% Fe2SO4 solution) gingival retraction cord, respectively. The gingival grooves models before and after gingival retraction were analyzed using the image precise mapper instrument; the gingival width and height of the gingival groove were compared using SAS6.12 software package.The changes of gingival width of the gingival groove before and after gingival retraction were not significant between the four groups. However, the gingival height of the gingival groove in the medicated gingival retraction cord group increased significantly [(0.423 + or - 0.348) mm before gingival retraction and (0.623 + or - 0.278) mm after gingival retraction] compared with the other three groups.The self-made colloid paste for gingival retraction is efficient like Expasyl gingival retraction paste and gingival retraction cord with potential clinical application, while the medicated gingival retraction cord can induce gingival shrinkage. Supported by Research Fund of Science and Technology Bureau of Huangpu District,Shanghai.