The hidden caries is a sub-type of the occlusal pit and fissure caries type, and is defined as a dentinal caries lesion nearby the occlusal surface of the tooth, seen on a radiograph, where the occlusal enamel remains intact or is minimally perforated. Optical detective technology has great potential in early diagnosis of hidden caries, but it still needs further study and improvement. Hidden caries should be diagnosed by radiographs in clinic. Hidden caries present the dentist with challenges in prevention, diagnosis, treatment planning, research,
and patient education. This review was focused on the research progress of its pathophysiology mechanism, clinical diagnosis and treatment.
