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The aim of this article is to introduce and illustrate the "Teflon tape technique," which provides good lucidity in combination with excellent isolation of the working field. It is intended to serve as a supplement to the gold standard rubber dam for the adhesive working dental practitioner. Primarily, the Teflon tape technique (Teflon is a registered trademark, and not affiliated with Teflon tape) is particularly suitable for the adhesive cementation of restorations with very thin margins. It allows free access to subgingival areas with variable gingival retraction. Furthermore, this principle can also be applied to other indications, such as Class V restorations or deep core buildups. The technique described is therefore flexible and easy to use. This combination allows a fast integration of the Teflon tape technique into the daily workflow of the dental practitioner. [ABSTRACT FROM AUTHOR]

Purpose: To investigate whether hemostatic agents have any detrimental effects on polyether impressions and plaster casts after a clinically viable cleaning protocol.Materials and Methods: A total of 60 human molar teeth were manually standardized, prepared, and subdivided into five groups (G): G0 (control/no contamination); G1 (ViscoStat Clear); G2 (ViscoStat); G3 (Astringedent); and G4 (Astringedent X). Each tooth was contaminated with a hemostatic agent for 3 minutes and cleaned with a 30-second air/water spray. Before and after contamination, an impression was taken and a plaster cast was poured. The impressions and plaster casts of all teeth were scanned using a light scanner. Data were matched using a three-dimensional analysis software that displayed color-coded maps. Means of the maximum positive/negative values and of the mean deviations in each group were calculated and compared. All color-coded maps were interpreted descriptively using the program's color scale, and all impressions and plaster casts were microscopically evaluated.Results: Values of mean deviations throughout all matched scans showed maximum values ranging from -30.1 to +17.5 μm. None of the groups showed significantly different deviation values or patterns when compared to each other. Impressions showed a thin, discontinuous coating for G2, G3, and G4; no changes were found for plaster casts.Conclusion: Presented deviations showed the same values and distribution patterns within all groups. A cleaning protocol of 30 seconds of air/water spray is sufficient to remove hemostatic agents, preventing effects to polyether impressions and plaster casts. However, ferric sulfate-containing hemostatic agents left discontinuous coatings on impression surfaces. [ABSTRACT FROM AUTHOR]

The purpose of this topic review is to give a general overview of gingival retraction agents used during prosthodontic treatment, and the possible difficulties connected to them that may be faced by the dentist. Hemostatic agents are important for successful gingival retraction and in achieving hemostasis. However, these agents may show numerous negative effects on the prosthodontic treatment and oral tissues of which the practicing dentist must be aware, and which will be elucidated in this review. PubMed and Google Scholar databases were searched for publications up to and including 2017. The following key words were used in different combinations: "hemostatic agent," "astringent," "astringency," "epinephrine," "ferric sulfate," "aluminum chloride," "hemorrhage control," "soft tissue," "hard dental tissue," "self-etch adhesive," "total-etch adhesive," "bond strength," "impression," "gypsum," "plaster cast," and "dental cast." In the last three decades the hemostatic agents used by practicing dentists have changed from epinephrine towards astringents, with AlCl3 and Fe2(SO4)3 now the most popular. All of the currently known hemostatic agents cause some local, temporary gingival tissue damage, but only epinephrine is known to elicit negative systemic effects. Studies concerning the influence of hemostatic agents on impression materials show highly contradictory results regarding the possible polymerization-inhibiting properties of hemostatic agents, probably due to the lack of standardization of methodology. Hemostatic agents seem to alter the dentinal surface properties making it more resistant to acid etching. Therefore the relatively low acidity of self-etch adhesives when compared to total-etch systems may not be strong enough to sufficiently etch a more resistant dentinal surface, and consequently may result in lower adhesive bond strengths. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate whether hemostatic agents (HA) show an effect on the retention strength (RS) of zirconia crowns luted to dentin abutments after cleaning with an air/water spray. Human molars (N = 60/n = 12) were prepared and zirconia crowns were milled. Prior to luting (Scotchbond Universal/RelyX Ultimate), molars were pretreated using HA: i. 25% AlCl3 (VSC), ii. 20% Fe2(SO4)3 (VS), iii. 15.5% Fe2(SO4)3 (AS), iv. 12.7% iron ion solution (ASX) and v. no pretreatment (control). Mastication simulation and pull-out tests were performed. Failure types were defined: cohesive 1—tooth root; cohesive 2—tooth crown; adhesive 1—cement on tooth; adhesive 2—cement on tooth and crown; mixed—adhesive/cohesive. Data were analyzed using 1-way ANOVA, post-hoc Scheffé, Pearson's chi-square-test and Ciba–Geigy table (p = 0.05). No RS differences between the tested groups were observed (p = 0.200). ASX fractured more cohesive 2 than the control group. VSC showed more cohesive 2 than adhesive 1 fractures. VS showed more adhesive 2 than mixed fractures. AS showed more cohesive 2 than adhesive 1 and more adhesive 2 than mixed fractures. ASX showed predominantly cohesive 2 fractures. RS was not affected when HA were cleaned off by 30 s of air/water spray prior to luting. HA still seem to weaken the dentin abutment, making it prone to cohesive fractures. [ABSTRACT FROM AUTHOR]