Where are carious lesions least likely to occur?

Carious lesions, commonly known as cavities, tend to occur in areas of the tooth that are more prone to plaque accumulation and less accessible for adequate cleaning. Fissures, proximal surfaces, and root surfaces are all locations where caries often develop due to their structural characteristics that can trap food particles and bacteria.

Fissures are small grooves in the enamel that are difficult to clean and can easily accumulate plaque. Proximal surfaces, which are the sides of adjacent teeth, can also trap food debris and plaque that is hard to reach with a toothbrush. Root surfaces may become exposed due to gum recession, leading to sensitivity and a higher likelihood of decay as they are not covered by enamel, making them more susceptible to caries.

Cusp tips, while they can develop carious lesions, are less likely to be sites where lesions occur compared to the aforementioned areas. This is because the cusp tips are more accessible to oral hygiene practices and often receive more cleaning attention from brushing and the action of chewing. Therefore, carious lesions are least likely to occur on cusp tips due to the combination of accessibility and lesser plaque retention compared to other areas of the tooth.