Just like you said, teeth decay on the biting surfaces. This usually happens in children. Because children's teeth are spaced apart, this type of teeth only decay on the chewing part. After the age of 12, when the teeth start to come together, that is, when contacts are formed, they decay on the interfacial surfaces. In other words, they decay on the interfacial surfaces in addition to the chewing surface. Over time, especially after the age of 35, the gums begin to recede and the roots of the teeth are exposed, and in this case, root caries occur. In other words, there is decay on the cheek surface of the tooth. In rare cases, decay can also occur on the parts of the tooth facing the tongue.