![]() | Only 14 pages are availabe for public view |
Abstract The aim of this study was to evaluate the effect of silica gel on dentin permeability, surface topography and leakage pattern in endodontically treated teeth as well as to assess its biocompatibility. The study was divided into 4 parts, in the first part, twenty dentin discs were prepared and divided into two equal groups which were treated with either silica gel or CO2 laser. A fluid transport apparatus was used to assess dentin permeability before and after surface treatment that was measured immediately and after 5, 15 and 30 minutes.The statistical comparison of the percentage change in dentin permeability showed that immediately, there was no statistically significant difference between the two groups. While after 5, 15 and 30 minutes, the mean percentage change of dentin discs treated with bioactive silica gel was lower than that recorded with the Laser treatment, and this difference was statistically significantly.The second part of the study was conducted to qualitatively evaluate the effect of bioactive silica gel and CO2 laser application on the resected root-end with and without the preparation of a retro-cavity using SEM. The selected samples were cleaned; shaped and obturated then root-end resection was Summary & Conclusions - 110 - performed. The samples were finally classified according to the method of root-end management into two equal groups. In the first group samples were left intact without performing a retrocavity after the root end resection and they were either left without surface treatment, treated with bioactive silica or with CO2 laser.For group I the root end resection resulted in creation of amorphous smear particles all over the resected surface. These particles partially obliterated the dentinal tubules. Application of the bioactive silica gel over the resected root end revealed even precipitation and full coverage of the surface entire at low magnification. However, at higher magnifications; there was evident discrepancy in the size of the silica crystals with some voids between them and even some patent dentinal tubules. While, when CO2 Laser was applied on the resected surface, there was evident dentinal melting and occlusion of the dentinal tubules. While in the second group samples were filled with either IRM only, treated with bioactive silica gel or treated with CO2 laser before IRM placement. SEM examination revealed the typical architecture of a zincoxide based filler dispersed in a homogenous matrix, with almost no evidence of any dentinal structures. |