Multifactorial Contributions to Central Incisor Tooth Morphology and the Presence of Black Triangles: A Case Study

Steven E. Kohane, Katelyn C. Means


Abstract: Dentists are often faced with patient concerns of smile esthetics in addition to oral health and should be equipped to help patients manage both.  Black triangle disease, or a lack of interdental papilla, is esthetically displeasing particularly in the central incisor region and has a hoard of etiologies ranging from gum disease to inherited tooth morphologic features.  Addressing patients’ esthetic concerns must first be met with understanding the causation of the black triangles before treatment can be rendered.  Genetic contributions are multifactorial, and this case report provides evidence for a case of a central incisor black triangles without other affected family members.

Background:   Black triangles are a prominent feature for those experiencing a lack of interdental papilla between central incisors and may dramatically affect the presentation of a person’s smile.  The aim of this case report is to convey the importance of managing patients’ esthetic chief complaints while addressing the etiology of the esthetic concern.

Case Description:  A 24-year-old man presented to his dental colleague with concern of his black triangle spaces.  The patient does not have gingival recession in the area of interest, and his biological mother and brother do not have black triangle spaces.  Pathology is not an issue, but instead inadequate length of the central incisor mesial contact area prevents the interdental papilla from reaching the contact.  Esthetics are a concern, but the patient is not interested in irreversible treatment for his healthy tissue.

Practical Implications: Dentists should be aware of the multifactorial contributions to patients’ esthetic concerns. Dentists should also be aware that meeting a patient’s expectations may require a more complex treatment plan than the patient expected.


black triangles; multifactorial inheritance; cosmetic dentistry; esthetics; gingival embrasures; interdental papilla; contact point; tooth morphology; odontometry

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