Effects of immediate loadings with different forces on immediate implant-bone ossification / 中国组织工程研究

ABSTRACT

BACKGROUND:Animal studies showed that functional early load or immediate load on immediate implant did not affect the prognosis of implant. OBJECTIVE:To analyze the effect of immediate loading with different forces on the binding surface of immediate implant bone ossification. METHODS:Six adult healthy male dogs were selected. Al teeth (three premolars) between cuspid teeth of lower mandible and the first molar were pul ed out. One implant (OSSTEM GSII) was immediately implanted, total y 36 implants. The vertical immediate loading by device was used on the implants at 24 hours after implantation. Grouped by the loading force values0, 10, 20 N on the left three implants of each dog from front to back, 30, 40, 50 N on the contralateral three implants of each dog, at a frequency of 1 Hz for 10 minutes every day. The implant stability quotient (ISQ) was tested using resonance frequency measurement instrument (OSSTELL) at 0 day, 4, 8, and 12 weeks. RESULTS AND CONCLUSION: With increased load forces, serum osteocalcin expression increased, and peaked on 20 N, but decreased in 30 N group, and lowest in 50 N group. At 4 weeks after immediate implantation, the ISQ values were slightly less than pre-implantation in each group, especial y the 50 N group. At 8 weeks after immediate implantation, ISQ values were increased in each group to different degrees. The increased degree of the 20 N group was maximal. At 12 weeks, a peak value was detected in each experimental group. The implants could bind to bone tissues to different degrees. The range of implant-bone interface formation was positively associated with time. Results indicated that the smal force cannot impact implant-bone ossification, but promotes it in a manner, but large force value (≥ 20 N) wil affect the stability of the implant-bone ossification.