Dental Assisting MN Licensure Exam
Review 2025/2026 Graded A
Chlorahexadine Stain - Found in Chewing Gum and Mouthrinses, Yellowish to green
brown in color
Endogenous Stains - Originate within the tooth through developmental and systemic
disturbances and CAN'T be removed
Exogenous Stains - Those that originate outside the tooth and are caused by
environmental agents
Extrinsic Stains - Are those stains that appear on the exterior of the tooth and CAN be
removed
Intrinsic Stains - Are caused by environmental source but CAN'T be removed because
the stain has become incorporated into the tooth structure
Black Stain - Thin Black line on the teeth near the gingival margin, Frequently found in
clean mouths. Extrinsic
Tobacco Stain - A very tenacious dark brown or black stain - Extrinsic
Brown or yellow stain - Most commonly found on the buccal surfaces of the maxillary
molars and the lingual surfaces of the lower anterior Incisors - Extrinsic
Dental plaque agents - Reddish brown stain on the interproximal and cervical areas of
the teeth. Caused by prescription mouth princes that contain chlorhexidine - Extrinsic
Nasmyths membrane - Light green or brownish stain caused by food stains in the
residue of epithelium, on newly erupted teeth - Extrinsic
Natural rubber polishing cups - More resilient and do not stain the teeth
Synthetic polishing cups - should be used for patients with latex allergies
Zirconium Silicate - Good for Gold, Exposed dentin, tooth colored restorations
Tin Oxide - Good on enamel and metallic restorations, mixed with water, alcohol,
glycerin
Flour of pumice - to Remove stains from enamel, High abrasiveness