Many clinicians encounter the dark staining of a patient’s tissues after the use of a hydrophobic cement. Fortunately, this is a challenge that is treatable, and even better, preventable! First, let’s take a look at the reasons behind why this pesky staining occurs in the first place. It’s all about the chemistry. Non-sealing cements allow saliva and bacteria to move between the temporary and preparation. Coagulum within cut tissues is a source of iron, which reacts with the hydrogen sulfide gas (rotten egg gas, H2S) produced by anaerobic bacteria in this septic environment. The reaction yields ferric sulfide—the harmless, yet annoying dark surface stain shown in the photo below.

All clinicians encounter challenges when it comes to tissue management. Even with high-quality, predictable tissue management products and techniques out there (such as Astringedent® X or ViscoStat® used with the Metal Dento-Infusor® tip), it helps to know a few tips and tricks for the extraordinary cases that inevitably come about from time to time.