Tartar, also known as dental calculus, is a hardened form of dental plaque that adheres firmly to the surfaces of teeth.
From Oral Bacteria to Plaque
The journey to tartar begins with dental plaque, a sticky, colorless or pale yellow biofilm on teeth. This film is a complex community primarily composed of bacteria, along with food particles, salivary proteins, and other oral debris.
Within minutes of cleaning teeth, a thin layer of salivary proteins and glycoproteins, known as the acquired pellicle, forms on the tooth surface, providing an initial attachment site for bacteria. Oral bacteria, notably Streptococcus mutans and other anaerobic species, are initial colonizers of this pellicle. These bacteria feed on sugars and starches consumed from food and drinks, metabolizing them and producing acids. This bacterial activity and the sticky extracellular matrix they produce contribute to the thickening and spreading of the plaque biofilm along the gumline and between teeth. At this stage, plaque remains soft and can be effectively removed through daily brushing and flossing.
The Hardening Process
If dental plaque is not consistently removed, it undergoes a mineralization process. This calcification occurs when minerals, primarily calcium phosphate, calcium carbonate, and magnesium phosphate, from saliva deposit into the plaque matrix. These inorganic salts precipitate within the organic framework of the plaque, becoming strongly bonded to the tooth enamel.
Plaque can begin to calcify into tartar within 24 to 72 hours if left undisturbed. However, the average time for mineralization is 10 to 12 days. Once the plaque has calcified into tartar, its rough and porous surface provides an even more favorable environment for additional plaque accumulation, which can then undergo further mineralization. Unlike soft plaque, tartar cannot be removed by regular brushing or flossing and requires professional dental instruments for removal.
Factors Influencing Formation
Several factors can influence the rate and extent of tartar formation. Inadequate oral hygiene, such as infrequent or ineffective brushing and flossing, is a primary contributor, allowing plaque to remain on tooth surfaces long enough to mineralize.
Dietary habits also play a role, as frequent consumption of sugary and starchy foods provides the necessary fuel for oral bacteria to produce plaque. Individual variations in saliva composition significantly affect tartar development. Saliva with higher concentrations of calcium and phosphate ions can accelerate the mineralization process. Additionally, certain genetic predispositions can influence an individual’s susceptibility to tartar formation. Habits like smoking are also associated with a higher risk of tartar buildup. Tartar commonly accumulates in areas close to salivary gland openings, such as the lingual surfaces of the lower front teeth and the buccal (cheek) surfaces of the upper molars, due to increased mineral exposure from saliva in these regions.