Dentin sealers' effect on the diameter of pulpal microvessels: a comparative vitalmicroscopic study

After crown preparation, exposed and untreated dentinal tubules can result in bacterial penetration into pulp. Treating the exposed dentin involves closing the tubules. Dentin sealers are often applied on a very thin dentin layer that covers the pulp chamber. In these cases, the sealers may have some effect on local micro-circulation through dentin. This study examined the acute effects of different dentin sealers on the vascular-diameter of pulpal vessels measured by vitalmicroscopic technique in rats. Gluma Desensitizer in Group 1 (n = 10), Seal & Protect with acid etching in Group 2 (n = 10) and Seal & Protect without acid etching in Group 3 (n = 10) were applied on a very thin layer of dentin in the left lower incisor of male Sprague-Dawley rats weighing 336 +/- 93SE/g. Saline served as the untreated control. After one-hour equilibration time, changes in vessel diameter were recorded with a digital camera connected to a microscope at baseline and at 5, 15, 30 and 60 minutes after the investigated materials were administered on dentin. The results were evaluated by ANOVA. In each group, diameter changes were averaged (compared to the baseline diameters) and standard errors of the mean were calculated for each examined time. The results suggest that Gluma Desensitizer caused the most severe pulpal vessel-diameter changes, followed by Seal & Protect with acid etching, while the least change was recorded in Seal & Protect without acid etching.