The purpose was to evaluate histomorphometrically the early healing at implants installed in sites prepared with either a sonic device or conventional drills.

Sixteen volunteer patients will be recruited. Two titanium mini-implants will be installed in the distal segments of the maxilla in recipient sites prepared with either a sonic device or conventional drills. Biopsies containing the mini-implants will be retrieved after 2 weeks in eight patients, and after 6 weeks in the other eight patients. Histomorphometric analyses will be performed

Inclusion Criteria:

• presence of an edentulous atrophic zone in the posterior segment of the maxilla
• height of the sinus floor ≥10 mm
• ≥ 25 years of age;
• smoking ≤10 cigarettes per day
• good general health
• no contraindication for oral surgical procedures
• not being pregnant.

Exclusion Criteria:

• presence of systemic disorders
• chemotherapy or radiotherapy
• smokers >10 cigarettes per day
• previous bone augmentation procedures in the same region.

Will be shared after publication

Each patient will receive two mini-implants, installed in recipient sites prepared in the distal segments of the maxilla either with a sonic device or drills. The two recipient sites will be selected prior the surgery, while the type of site preparation will be randomly decided. A researcher, neither involved in the selection of the patients nor in the surgical and prosthetic treatment, carried out electronically the randomization (randomization.com). Sealed opaque envelopes will be prepared and opened at the time of surgery and they will report the position of the sonic sites so that the surgeon will be masked about site preparation type until the surgery. The site will be indicated as mesial or distal position if the two sites will be located in the same quadrant of the maxilla, or as right or left if they will be located in opposite quadrants of the maxilla.