Supracrestal tissue attachment (STA) is a relatively new term that was introduced in 2017 following the World Workshop on the Classification of Periodontal and Peri-implant Diseases and Conditions, co-sponsored by the American Academy of Periodontology (AAP) and the European Federation of Periodontology (EFP), which included expert participants from all over the world. It has replaced the term biological width, and refers to the junctional epithelium and supracrestal connective tissue. This article provides an updated review of the anatomy of STA, highlights the negative effects of violation and discusses its clinical relevance in restorative dentistry, including the use of crown lengthening. The impact of implants on STA is highlighted, and a summary of the relevance of STA in implant dentistry is also discussed. CPD/Clinical Relevance: To allow dental practitioners to have more confidence providing adequate function, comfort, and aesthetics in the dentition, while maintaining periodontal health.