Integrative review on the use of hyaluronic acid for closing black triangles

Abstract

Interdental papilla loss is an aesthetic concern often referred to as black triangles. These black triangles can result from periodontitis, orthodontic treatment, and anatomical differences due to the effects of these factors on the critical distance between the contact point and the bone crest. The visible interproximal space in the cervical region below the contact point, caused by incomplete filling of the interdental embrasure by the papilla, plays a significant role in smile aesthetics and is a common source of patient complaints. Various treatment options exist, both invasive and non-invasive, for this issue. Non-surgical approaches for restoring lost interdental papillae are being developed, including hyaluronic acid injections, which are minimally invasive treatments. This study conducted a literature analysis to demonstrate the relationship between the biological properties of hyaluronic acid and the clinical predictability of volumetric papilla restoration. The method consisted of analyzing articles such as literature reviews, dissertations, and full scientific studies published in Portuguese between 2019 and 2025. Hyaluronic acid injection into the interdental papilla may help restore soft tissue volume and improve patient satisfaction by reducing black triangles that compromise aesthetics. In conclusion, this study suggests that hyaluronic acid injection can increase soft tissue volume and reduce black triangles, promoting better aesthetic outcomes.