Did you know that pores can be categorized into 3 types? Different factors cause various pore shapes. Here's a breakdown of each one so that you can find the right skincare products and ingredients to address them. (1) U-shaped pores. If you notice your pores are u-shaped, they're likely caused by reduced skin elasticity and dehydration. (2) O-shaped pores. This pore type often appears on the T-zone and is caused by inflammation from acne and increased sebum production. (3) Y-shaped pores. Gravitational effects on the skin and reduced elasticity cause Y-shaped pores. They also tend to appear on the cheeks and can take the shape of a water drop.