Takehiro Watanabe

Assessment of the Quality of Newly Formed Bone around Titanium Alloy Implants by Using X-Ray Photoelectron Spectroscopy

The aim of this study was to evaluate differences in bones quality between newly formed bone and cortical bone formed around titanium alloy implants by using X-ray photoelectron spectroscopy. As a result of narrow scan measurement at 4 weeks, the newly formed bone of C1s, P2p, O1s, and Ca2p were observed at a different peak range and strength compared with a cortical bone. At 8 weeks, the peak range and strength of newly formed bone were similar to those of cortical bone at C1s, P2p, and Ca2p, but not O1s. The results from this analysis indicate that the peaks and quantities of each element of newly formed bone were similar to those of cortical bone at 8 weeks, suggestive of a strong physicochemical resemblance.

Potential for acceleration of bone formation after implant surgery by using a dietary supplement: an animal study

Dental implant treatment is an effective modality to restore lost aesthetic and masticatory functions. However, healing after implant surgery takes at least 3-6 months. This prolonged healing period poses several difficulties for individuals with a large edentulous area and decreases their quality of life. Consequently, shortening the healing period and accelerating final prosthesis placement after surgery is very clinically important. Peri-implant bone formation may be enhanced by systemic approaches, such as the use of osteoporosis supplements, to promote bone metabolism. To confirm whether intake of a supplement developed for osteoporosis, synthetic bone mineral (SBM), was effective in accelerating peri-implant bone formation as part of the healing process after implantation. Twenty-four 5-week-old female Wistar rats were randomly assigned to receive a standardised diet without (control group, n = 12) or with SBM (n = 12). The rats had implant surgery at 8 weeks of age under general anaesthesia. The main outcome measures were bone mineral density (BMD) and pull-out strength in the implant and femur, which were compared between the groups at 2 and 4 weeks after implantation using the Mann-Whitney U test. BMD was significantly greater in the SBM group at 2 and 4 weeks after implantation compared to the control group. Pull-out strength was significantly greater in the SBM groups at 2 and 4 weeks after implantation compared to the control group. This study demonstrated that SBM could be effective in accelerating peri-implant bone formation during the healing period after implantation.

Changes in Bone Quality of the Femoral Diaphysis Induced by High-Level Fluorine Ingestion in Ovariectomized Rats

Ovariectomized rats were fed a diet containing minerals at high concentrations, such as Ca, P, and F (high-mineral diet), and changes in the femoral diaphysis were investigated after 24 weeks. The femur was mainly red and partially orange on the color scale of the 3D-map in Groups A and B, showing a high BMD. The region adjacent to the marrow cavity was yellow, showing a lower BMD than that in the outer region of the femur. In Group C, the red area was small in the outer region and the inner region was mainly yellow and green on the color scale. The inner region adjacent to the marrow cavity showed a view of unevenly resorbed bone, and the BMD was lower than those in Groups A and B. Incorporation of F into the body influences the apatite crystal structure and crystal growth, which subsequently influences adsorption of F to crystals and structural changes. Therefore, it is important to ingest F at the optimum concentration.

Effect of a dietary supplement on peri-implant bone strength in a rat model of osteoporosis

PURPOSE Osteoporosis contributes to impaired bone regeneration and remodeling through an imbalance of osteoblastic and osteoclastic activity, and can delay peri-implant bone formation after dental implant surgery, resulting in a prolonged treatment period. It poses several difficulties for individuals with large edentulous areas, and decreases their quality of life. Consequently, prompt postoperative placement of the final prosthesis is very important clinically. Peri-implant bone formation may be enhanced by systemic approaches, such as the use of osteoporosis supplements, to promote bone metabolism. We aimed to confirm whether intake of synthetic bone mineral (SBM), a supplement developed for osteoporosis, could effectively accelerate peri-implant bone formation in a rat model of osteoporosis. METHODS Thirty-six 7-week-old ovariectomized female Wistar rats were randomly assigned to receive a standardized diet with or without SBM (Diet with SBM group and Diet without SBM group, respectively; n=18 for both). The rats underwent implant surgery at 9 weeks of age under general anesthesia. The main outcome measures, bone mineral density (BMD) and pull-out strength of the implant from the femur, were compared at 2 and 4 weeks after implantation using the Mann-Whitney U test. RESULTS Pull-out strength and BMD in the Diet with SBM group were significantly greater than those in the Diet without SBM group at 2 and 4 weeks after implantation. CONCLUSIONS This study demonstrated that SBM could be effective in accelerating peri-implant bone formation in osteoporosis.

A New Synthetic Diet Increased Bone Mineral Density and Strength of Ovariectomized Rat

This study aimed to determine changes in Bone Mineral Density (BMD) and bone strength of ovariectomized rats fed a synthetic diet of Mg, Zn, and F incorporated with carbonate apatite. Group 1 (n=4) was fed a Normal Mineral Diet (NMD) and Group 2 (n=4) was fed the Synthetic Diet (SD: 0.74% Ca, 0.48% P, 0.10% Mg, 365.4 ppm Zn, 51.01 ppm F and 0.27% CO3). Rats were sacrificed after eight weeks and the femur was isolated. The micro-CT results showed that values of BMD for Group 2 were higher than those of Group 1. Bone strength values of Group 2 measured by a 3-point bending test were significantly higher than those of Group 1. These results indicated that Group 2 stimulated bone quality, increased BMD and bone strength. The SD has the potential to prevent bone loss and as an osteoporosis therapy.