Comparative evaluation of biologic, surgical and prosthetic success of Tissue level and bone level implants.

The choice between tissue-level (TL) and bone-level (BL) implants is dictated by a trade-off between biological stability and aesthetic flexibility. Tissue-level implants excel in the posterior regions due to their "one-stage" surgical protocol and a built-in transmucosal collar that shifts the implant-abutment interface away from the bone, effectively reducing crestal bone resorption and simplifying hygiene maintenance. Conversely, bone-level implants are the gold standard for the aesthetic zone, as their submerged placement allows for precise control over the emergence profile and soft-tissue contouring. While both systems demonstrate comparable high survival rates, TL implants offer superior protection against peri-implantitis via a machined smooth surface, whereas BL implants provide the surgical versatility required for complex grafting and high-demand anterior restorations.