The symbols on a dental chart indicate what types of repairs a person has had performed on their teeth and what problems require treatment. Dentists usually differentiate prospective repairs from completed ones using two different colors, often blue and red. Which two colors the dentist uses, as well as the particular symbols she uses to indicate certain problems and procedures, can vary across individual dentists. Some dentists also use a third color, typically green, to indicate calculus, hardened plaque.
One of the most common symbols on a dental chart is an outlined tooth. This symbol indicates a porcelain-fused-to-metal crown if the lines are parallel, while crosshatching denotes a steel crown, and no lines at all indicate a ceramic or all porcelain crown. Several outlined teeth connected together indicate a Maryland bridge. Dentists indicate completed crowns and bridges with blue and prospective work using red. A similar symbol is an outline drawn inside the edge of the tooth, which corresponds to a porcelain veneer.
Letters are a common symbol found on dental charts. A red "X" that covers an entire tooth indicates that the tooth requires removal, while a blue "X" symbolizes an absent tooth. Red and blue "S" symbols indicate required and completed sealant applications, respectively.
With one exception, arrows indicate a tooth that is out of place. Horizontal arrows are always red, and they indicate that a tooth is horizontally impacted. A red arrow pointing up indicates a tooth is extruded, while a downward pointing red arrow denotes impacted food.