Abstract
Objective: Low-intensity pulsed ultrasound (LIPU) treatments have been used for intractable fractures in the orthopedics field. In this study, we examined the influence of LIPU for osseointegration in bone defects between titanium implants and bone tissue after primary operation for two-stage dental implants and then evaluated whether the LIPU is effective in reducing the period between the first and second operations.
Materials and methods: Both sides of the mandibular premolars of beagle dogs were extracted prior to the primary dental implant operation. After three months, titanium implants were placed in both sides. One week after implantation, the irradiation was started for the left sides. The right sides (controls) were not LIPU. Two kinds of irradiation pattern (1.0 MHz or 3.0 MHz) were administered 15 minutes per day for seven days. The dogs were sacrificed the day after the final irradiation was performed. The specimens were fixed with 10% neutral buffered formalin and embedded with MMA resin. The quantity of newly formed bone was analyzed by a color image system with 30μm thin sections after histochemical staining.
Results: No inflammation was observed for control and experimental sites. According to the color image analysis, with the 3.0 MHz irradiation newly formed bone occupied 34.7% of the new bone measurement area and 17.3% with the 1.0 MHz irradiation, while only 11.2% of the new bone measurement area was occupied for the control sides, indicating that the irradiation with 3.0 MHz LIPU was almost three times as effective as non LIPU for osseointegration.
Conclusion: These results suggested that 3.0 MHz LIPU treatment was useful to reduce the period between primary and secondary operation of dental implants.
