Standard Implants With Bone Regeneration vs Short Implants

Inclusion Criteria: * All the patients with a distal edentulism Kennedy -Applegate Class II in the posterior mandible or maxilla, with residual bone height from the top of the crest to the opposite landmark (the alveolar nerve for the lower and the sinus cavity for the upper) between 5 and 7 millimeters. The bone peak on the last tooth before the edentulous space must be positioned from 2 to 4 mm from the CEJ. (X-ray evaluation by periapical film on a Rinn Holder). * All patients with at least 3 mm of keratinized tissue on the edentulous crest. In case of absence of this prerequisite, three months before the keratinized tissue is augmented by a ephytelium-connective tissue graft harvested from the palate. * Patients with edentulous distal sites Exclusion Criteria: * Heavy smokers (more than 10 cigarettes /day) * Patients with active periodontal disease: full mouth plaque index (FMPI \> 20%) and Full mouth bleeding index (FMBI \> 20%). * Patients with less of 5 mm of bone width. * Patients with systemic conditions or under prescription of medications that contraindicate oral surgery