Mini-implant stability analysis at different healing times before loading

This study aims to biomechanically analyze a mini-implant at different healing times before loading. Sixty-four mini-implants with (12 +/- 1) N x cm insertion torque were placed in the low jaw of eight beagle dogs. The test mini-implants remained in the low jaw for 0, 1, 3, and 8 weeks of bone healing and for an additional 10 weeks under a force of 0.98 N. The unloaded control implants were further divided into four groups (1, 3, 8, and 10 weeks). Maximum removal torque (MRT) testing was performed to evaluate the interfacial share strength of each group. Surface analysis of the removed implants was performed by scanning electric microscope (SEM). The MRT for the loading implants at 0, 1, 3, and 8 weeks of healing were 4.10, 4.25, 2.42, and 4.42 N x cm, respectively. During the healing process, the removal torque values of the 3-week implants were significantly lower than those of the other healing groups (P < 0.05). The unloaded 3-week implants also had lower removal torques (P < 0.05). The implant surface of