Plaque and calculus are the two types of deposits that adhere to teeth and are the primary causes of gum disease. While they may sometimes be discussed interchangeably, there is a clear difference between the two forms of buildup and how they affect your oral health. Plaque is characterized as a soft, sticky layer of acid producing bacteria that constantly forms on the teeth and along the gum line as a result of normal function and food consumption. It is easily removed from the teeth with regular brushing and flossing. However, when not removed regularly with proper oral hygiene, the acid secretions eventually cause irritation and inflammation to the gum tissue and can result in tooth decay. If the plaque is allowed to remain for too long, it combines with minerals in the saliva and hardens on the teeth and becomes what is known as calculus, also referred to as tartar. Calculus, unlike plaque, is a hard mineralized substance that deposits on the teeth, which builds up in layers and thickness over time. It creates an uneven surface on the teeth that allows for additional plaque and ultimately calculus to form over it. Like plaque, it harbors toxin emitting bacteria that can irritate and inflame the gum tissue and over time, cause gum disease and recession of the gum tissue. Unlike plaque, once calculus has formed on the teeth, it cannot be removed by everyday brushing and flossing, and requires a professional dental procedure to remove. Depending on the extent of calculus buildup, a specialized multi visit procedure may be required to remove it all. If plaque and eventually calculus are allowed to remain on the teeth, over time, the irritation and inflammation of the gums can progress to gingivitis and eventually periodontitis. It is important to practice good oral hygiene at home and maintain regular hygiene appointments so your doctor can monitor any potential risks.