What classification of decay is located on the gingival third on the facial or lingual surfaces of teeth

Smooth-surface decay.

Explanation:

Dental caries is a multifactorial infectious disease of the hard tissues of the tooth (enamel and dentin) that arises on the surface of the tooth and can spread to the pulp. Smooth-surface decay are dental caries that originate on the smooth surfaces of the proximal general teeth, or in the gingival third of the facial and lingual surfaces. This cavity forms when plaque builds up and bacteria are not killed on the flat surface of the teeth.

blood enters the heart through two large veins, the inferior and superior vena cava, emptying oxygen-poor blood from the body into the right atrium of the heart. as the ventricle contracts, blood leaves the heart through the pulmonic valve, into the pulmonary artery and to the lungs where it is oxygenated.