Abstract

Conventionally, sleep duration has been considered the primary metric for evaluating the impact of sleep on overall health and pain modulation. Extensive evidence exists demonstrating a bidirectional relationship between sleep duration and pain where both sleep deprivation and excessive sleep contribute to hyperalgesia, neuro inflammation, and central sensitization resulting in a U-shaped relationship. This relationship is particularly evident in pain conditions of the orofacial region which are governed by the trigeminal nerve complex, such as temporomandibular disorders, burning mouth syndrome, headaches, and neuralgias. However, recent studies suggest a critical paradigm shift towards sleep regularity which reflects the consistency of the sleep-wake cycle that could be a more fundamental and independent determinant of systemic homeostasis than absolute sleep quantity itself. Irregular sleep patterns and circadian misalignment disrupt endogenous pain inhibitory systems and exacerbate one’s vulnerability to physical pain, psychiatric disorders, and even mortality, regardless of total sleep hours. Various metrics, including social jetlag, standard deviation of midsleep timing, interdaily stability, sleep regularity index, and composite phase deviation have been developed to quantify these variations. This review highlights the emerging clinical significance of sleep regularity in overall well-being and its relationship with pain management. To effectively manage chronic orofacial pain in dentistry, future research should focus on standardizing regularity metrics, utilizing digital healthcare wearables for long-term objective monitoring, and developing personalized chronotype-based interventions. Establishing sleep regularity in a dental patient could serve as a core therapeutic milestone in breaking the vicious cycle of chronic orofacial pain. (J Korean Dent As soc 2026; 64(9): 319-330)