To determine whether you have dental calculus, you can use a mirror to observe the lingual side of the lower front teeth or the buccal side of the maxillary back teeth for yellow-brown or gray-yellow plaque. 1. Calculus is mineralized plaque and soft scale deposited in the oral cavity similar to the shape of the teeth, with a hard texture and sometimes a bad taste. 2. Dental calculus is easy to be attached to a large number of bacteria, secretion of toxins on the tartar, corrosion of dentin to invade the gums as well as periodontal tissues, while combined with the mechanical stimulation of the calculus itself, resulting in gingival damage, resulting in loosening of the teeth, periodontal disease. Since calculus itself is hard and cannot be removed by brushing alone, it is recommended that you seek medical attention as soon as possible to have your teeth cleaned or undergo periodontal treatment using ultrasonic waves or other means.