Definitive diagnosis of early enamel and dentin cracks based on microscopic evaluation.

UNLABELLED: The diagnoses of cracked teeth and incomplete coronal fracture have historically been symptom based. The dental operating microscope at 16x magnification can fundamentally change a clinician's ability to diagnose such conditions. Clinicians have been observing cracks under extreme magnification for nearly a decade. Patterns have become clear that can lead to appropriate treatment prior to symptoms or to devastation to tooth structure. Conversely, many cracks are not structural and can lead to misdiagnosis and overtreatment. Methodic microscopic examination, an understanding of crack progression, and an appreciation of the types of cracks will guide a doctor to make appropriate decisions. Teeth can have structural cracks in various stages. To date, diagnosis and treatment are very often at end stage of crack development. CLINICAL SIGNIFICANCE: This article gives new guidelines for recognition, visualization, classification, and treatment of cracked teeth based on the routine use of 16x magnification. The significance of enamel cracks as they relate to dentinal cracks is detailed.