In mandibular posterior sextants an insufficient bone quality or volume may contraindicate implant placement. Crestal bone resorption, supra-eruption of teeth, and minimal bone coronal to the mandibular canal are the principal reasons for not placing dental implants. The available prosthetic space is also a major factor in determining surgical and prosthetic treatment. Various surgical approaches are used to create adequate bone volume in the posterior mandible, thereby allowing the possibility for implant placement. The therapeutic choice is made depending upon residual bone volume and available prosthetic space. The risks and disadvantages of the various techniques must be seriously evaluated and explained to the patient.