Conventional and Ultrasonic Implant Site Preparation

Inclusion Criteria: indications for two implant-supported single crowns with immediate loading in the upper or lower arch (in the incisor, canine or premolar area), based on accurate diagnosis and treatment planning; 2) implants can be in the same or in different quadrants; 3) implant sites must be performed in similar bone quality (i.e. both maxillary or mandibular); 4) the bone crest must be healed (at least three months elapsed after tooth loss); 5) presence of a residual bone crest with an adequate volume to allow the insertion of a 3.8x11.5 mm implant without any kind of regenerative procedure; 6) age of the patient \>18 years; 7) patient willing and fully capable to comply with the study protocol; 8) written informed consent given; Exclusion Criteria: 1. acute myocardial infarction within the past 2 months; 2. uncontrolled coagulation disorders; 3. uncontrolled diabetes (HBA1c \> 7.5%); 4. radiotherapy to the head/neck district within the past 24 months; 5. immunocompromised patient (HIV infection or chemotherapy within the past 5 years); 6. present or past treatment with intravenous bisphosphonates; 7. psychological or psychiatric problems; 8. alcohol or drugs abuse Local exclusion criterion is the presence of uncontrolled or untreated periodontal disease (full mouth plaque score and full mouth bleeding score \> 25%)