Preliminary report: laboratory-induced stain removal as assessed by environmental scanning electron microscopy

Environmental scanning electron microscopy (ESEM) was employed to observe stain removal during brushing with Arm & Hammer Dental Care and Crest Regular Toothpaste. ESEM allows serial examinations of the same sample, and does not require a destructive preparative process. Three extracted molars were cleaned, placed into a 96-hour broth culture of Streptococcus mutans, and stain was produced with undiluted chlorhexidine rinse, concentrated coffee and tea for a period of 23 days. After staining, the teeth were examined by ESEM, then brushed using a toothbrushing machine. Imaging was repeated after 5, 10, 15 and 30 seconds of brushing. As seen with ESEM, the Arm & Hammer product had different effects than those from the distilled water control, suggesting something other than that expected from abrasive and mechanical forces alone. There were also differences from the Crest dentifrice removal on this single sample, suggesting a possible difference between the two products. Further studies are needed to confirm and explain these effects.