Shiva has always been referred to as Triambaka because he has a third eye. The third eye does not mean someone’s forehead cracked and something came out! It simply means another dimension of perception has opened up.
Oṁ Namaḥ Śivāya (Sanskrit ॐ नम शिवाय) is believed to be a powerful healing mantra, beneficial for all physical and mental ailments. Soulful recitation of this mantra, especially during meditation can bring peace to the heart and joy to the [Ātman] or soul