Evaluation of osseointegration of dental implant with and without primary stability: An experimental study on sheep

Abstract

Background and objective: Primary implant stability is a prerequisite for reaching and maintaining osseointegration. This study aimed to check the amount of osseointegration of dental implant when placed with and without primary stability, clinically, radiological, and histologically. Methods: The experimental study includes four male sheep with a weighted mean of 50 kg and 2 to 4 years old. Forty implants placed, divided into two groups, 20 implants without primary stability as a study group and other 20 implants with primary stability. After intramuscular sedation and local anesthesia, the implant site performed in the inferior border of the basal bone of mandible drilling to 4.3 mm in diameter and 8 mm in length. Forty implants were inserted, 20 implants in the study group (3.3 mm diameter and 8 mm length) and 20 implants in the control group (4.3 mm diameter and 8 mm length), after 3 months the 4 sheep were sacrificed and the universal torque ratchet and Periotest was used to measure the stability of the dental implants clinically. Radiologically, Cone Beam Tomography (CBCT) was taken using ImageJ software for measuring density in both groups. Histologically also ImageJ software used for measuring thread width, the distance between threads and amount of cortical bone at bone-implant contact. Results: Non-significant difference between both groups. Forty implants successfully tolerated a 30 N/cm reverse torque test, and the results of the Periotest were nonsignificant. Cone Beam Tomography (CBCT) showed no sign of bone radiolucency, and the density result was non-significant. The histological evaluation confirmed the formation of bone around dental implants in both groups and ImageJ software measurement showing no significant difference between study and experimental groups in depth of threads, the distance between threads and amount of cortical bone in the area of bone-implant contact. Conclusion: Dental implants had the same chance to Osseointegrate in the absence or presence of primary stability at three months follow up.