Plastic and metal combs have sharp tooth and therefore not always smooth. They are actually harsh and may scratch your scalp. Wooden combs, on the other hand, are soft and polished. When you comb with wooden combs you experience a much softer feel than plastic or metal combs. - Wooden combs always helps to distribute oil from your scalp to hair and this prevents your hair from dying out. People with sensitive scalp must use wooden comb only.