OBJECTIVETo investigate the osteointegration of with self-drilling and self-tapping microscrew implants under immediate loading histomorphometrically.

METHODSThe buccal side of upper and lower jaws of three dogs was chosen as implant receipt site. Each dog accepted 8 implants (4 self-drilling and 4 self-tapping implants). Approximately 1.47-1.96 N continuous and constant forces were immediately applied between two microscrew implants with nickel-titanium coil spring for 9 weeks. Undecalcified sections of implants and surrounding tissue were studied with light microscope and fluorescent microscope.

RESULTSOsteointegration was seen in all samples and no fibrous tissue was seen between bone and implant. More original bone was seen in self-drilling group. Modeling and remodeling were more active in self-tapping group. Bone-to-implant contact values were statistically significant higher in self-drilling group [(41.7 +/- 10.7)%] than in self-tapping group [(25.9 +/- 8.0)%, P<0.01].

CONCLUSIONSImmediate loading had no influence on osteointegration in both self-drilling and self-tapping groups. The rates of bone-to-implant contact were higher in self-drilling group.