Neutralizing effects of an anti-vascular endothelial growth factor antibody on tooth movement.

Our recent studies demonstrated that local administration of recombinant human vascular endothelial growth factor (rhVEGF) during experimental tooth movement enhanced the number of osteoclasts and the rate of tooth movement. The purpose of this study was to examine the effect of anti-VEGF polyclonal antibody on osteoclastic differentiation, the amount of tooth movement, and the degree of tooth relapse in 30-day-old mice. First, these mice were subjected to various doses of anti-VEGF polyclonal antibody, with tooth movement for three days. In the next study, daily injections of 10-microg antibody were administered for 18 days during the experimental tooth movement. The amount of tooth movement was measured as in our previous study. Furthermore, in the third study, we administered daily injection of 10-microg antibody and measured tooth relapse after the experimental tooth movement for 45 days. The osteoclasts number in 10- and 50-microg antibody two-time injection group was significantly smaller than that in the controls (P < .05). The number of osteoclasts was decreased more substantially by daily injection of 10-microg antibody, showing more significant differences from the controls (P < .01). The amount of tooth movement was significantly less in the experimental group than in the controls on days 15 and 18 (P < .05). Furthermore, the amount of relapse in the experimental group was significantly less than that in the controls on days 9 and 11 after removal of the appliance (P < .05). These results show that the treatment of anti-VEGF polyclonal antibody markedly reduced the osteoclasts number and inhibited the amount of tooth movement and relapse of moved teeth.

Guided bone regeneration to repair an alveolar bone defect in a girl whose cleft lip and palate had been repaired.

We report the case of a girl aged 10 years whose alveolar bony defect was closed with a polytetrafluoroethylene membrane, which was incorporated in bone after 4 months. We suggest that the principle of guided bone regeneration can be used to repair cleft defects provided that the mucoperiosteal flaps are handled carefully and that good anti-infective measures are taken to prevent early exposure and microbial contamination of the membrane barrier.

Bactericidal effects of acidic electrolyzed water on the dental unit waterline.

Many studies have been conducted in the United States regarding the microbial contamination of dental unit waterline, but not in Japan. Recently, acidic electrolyzed water has been used in the medical and dental fields. In this study, we investigated the bactericidal effects of the temporary inflow of acidic electrolyzed water on microbial contamination of the dental unit waterline. First, in order to observe the daily bacterial contamination of the dental unit waterline, water samples were collected at the end of handpieces and three-way syringes before the inflow of acidic electrolyzed water. They were cultured to detect viable bacteria. Later, the inflow of acidic electrolyzed water was conducted through the piping box of the dental unit. Before starting operation on next day, water samples were collected and cultured, as described above. The mean viable bacteria count was 910 -/+ 190 CFU/ml at the end of handpieces, and 521 -/+ 116 CFU/ml at the end of three-way syringes before the inflow of acidic electrolyzed water. However, bacteria were detected in only small numbers at the end of handpieces and three-way syringes on the next day. These results indicated that acidic electrolyzed water could be applied as an appropriate measure against bacterial contamination of the dental unit waterline.

Effect of insulin-like growth factor-I (IGF-I) on femoral bone modeling in growing mice.

The time-dependent effects of daily dosing of IGF-I (1.21 mg/g) on the linear growth of the femur were investigated in mice. The femoral length and volume and the number of osteoclasts were significantly greater after IGF-I injection as compared to the non-injected control, suggesting that the IGF-I imbalance might cause a quick turnover cycle of the bone resulting in the altered femoral modeling.