Dental question about taxonomy:condition:dental-calculus
Dental calculus is hardened plaque bonded to tooth surfaces; professional scaling removes it because brushing cannot remove the deposit.
The short answer
Dental calculus, also called tartar, is plaque that has hardened through mineral deposition from saliva and cannot be removed reliably with ordinary brushing.

What is the direct answer?
What does this question mean?
Plaque is a soft bacterial film that collects at the gumline; calculus is the rough, firmly attached mineralised form. Its uneven surface retains more plaque and can irritate the gingiva, causing redness, swelling, or bleeding.
What can you do next?
Brush twice daily with fluoride toothpaste and clean between teeth with floss or interdental brushes to control new plaque. Book a professional scale and polish when deposits are present, and do not scrape them with household tools because the enamel and gum can be injured.
When should you seek dental care?
Arrange care when deposits are visible, gums bleed repeatedly, breath odour persists, or teeth feel loose. The dentist or hygienist may measure gum pockets after scaling to check whether calculus has contributed to periodontal disease.
What should you ask the dentist?
Ask where the deposits are located, whether gum pockets or bone loss are present, and which interdental tool fits each space. Ask how often your gum health should be checked and whether root-surface cleaning is needed below the gumline.
Frequently asked questions
Can tartar be brushed off?
No. Brushing controls soft plaque but attached calculus requires professional scaling.
Why do my gums bleed around tartar?
Plaque retained around the rough deposit can inflame the gingival tissue and make it bleed when touched.
