What is the correct term for a yellow-coloured, hard deposit often visible in the oral cavity due to poor hygiene?

The term "supragingival calculus" refers to the hard yellowish deposit that often forms above the gum line due to inadequate oral hygiene. This type of calculus develops from mineralized dental plaque, which is composed of bacteria, food particles, and saliva. When plaque is not regularly removed through brushing and flossing, it can harden and become calculus.

Supragingival calculus is typically found on the teeth, especially on the buccal surfaces of the molars and the lingual surfaces of the lower incisors, where saliva flows. Its presence is a visible indicator of poor oral hygiene practices, as it becomes more prominent when brushing and flossing are neglected.

In contrast, biofilm refers to a thin, sticky film of bacteria that forms on teeth, but it is not specifically a hard deposit and can describe a wider range of microbial growth. Plaque is a soft, sticky accumulation of bacteria that can lead to the formation of calculus if not cleaned properly; however, it is not the hard deposit itself. Subgingival calculus forms below the gum line and may not be visible without clinical examination, distinguishing it from the supragingival type that is readily seen.