Horizontal bone augmentation: the decision tree.

The emergence of implant dentistry has led to the need for bone augmentation procedures. With the removal of a tooth, there is an inevitable three-dimensional (3D) loss of alveolar bone. More often than not, horizontal bone loss occurs at a faster rate and to a greater extent compared to vertical bone loss. This led to the development of several horizontal bone augmentation techniques, such as guided bone regeneration, ridge expansion, distraction osteogenesis, and block grafts. These proposed augmentation techniques aim to place the implant in an ideal 3D position for successful restorative therapy. The literature has shown that horizontal bone augmentation is fairly predictable if certain criteria are fulfilled. However, with numerous techniques and materials currently available, it is difficult to choose the most suitable treatment modality. A search of the literature available was conducted to validate the decision-making process when planning for a horizontal ridge augmentation procedure. The decision tree proposed in this paper stems from the 3D buccolingual bone width available at the site of implant placement (⋝ 3.5 mm, < 3.5 mm, or 4 to 5 mm). In each dimension, techniques are advised after considering factors such as the tissue thickness, the arch position, and the availability of autogenous bone. The decision tree provides insight on how clinicians can choose the most appropriate and predictable horizontal ridge augmentation procedure to minimize unnecessary complications.