Photobiomodulation (PBM) is a noninvasive therapeutic technique using nonionizing light sources, such as lasers and LEDs, within the visible and near-infrared spectrum. The therapeutic effects depend on the interaction between specific light wavelengths and biological tissues, influenced by the tissue’s optical properties and the light system’s characteristics. PBM is nonthermal, relying on endogenous light-absorbing molecules like chromophores and cytochromes to induce beneficial photophysical and photochemical reactions at various biological levels. Widely used in dentistry to enhance conventional treatments, PBM can also be a primary intervention for conditions like oral mucositis in cancer patients. The primary goals of PBM are pain management, immunomodulation, and tissue repair through wound healing or regeneration. PBM’s mechanisms include enhanced ATP production, activation of transcription factors and signaling pathways, and effects on cell proliferation and differentiation. Understanding the intricate processes and factors influencing PBM is essential for optimizing its clinical efficacy.