Final answer:
The brushing method described is called lateral movement of the cheeks, which is taught to children but not recommended for adults.
Step-by-step explanation:
The brushing method described, where the teeth are clenched together, the brush is moved in a circular motion over both arches, and brushing is done in and out on linguals, is called lateral movement of the cheeks. This method is often taught to children, as their teeth are closely spaced and they may have difficulty using other brushing techniques. However, it is not recommended for adults, as it can be damaging if done too vigorously.