Effect of MBCP block as carrier of rhBMP-2 in combination with ePTFE membrane on bone formation in rat calvarial defects / 대한치주과학회지

PURPOSE: The carrier used as delivery agent for bone morphogenetic proteins(BMPs) should also act as a scaffold for new bone formation. Moreover, bone formation should be predictable in terms of the volume and shape. This study examined the osteogenic effect of macroporous biphasic calcium phosphate (MBCP) block combined with ePTFE membrane as a carrier for recombinant human bone morphogenetic proteins (rhBMP-2). In addition, the additive effect of ePTFE membrane on bone formation was evaluated. MATERIALS AND METHODS: Eight-millimeter critical sized calvarial defects were created surgically in 28 male Sprague-Dawley rats. The animals were divided into 2 groups containing 14 animals each. The defects were treated with either rhBMP-2/MBCP block (rhBMP-2/MBCP group) or rhBMP-2/MBCP block/ePTFE membrane (rhBMP-2/MBCP/ePTFE group). A disc-shaped MBCP block (3 mm height and 8 mm diameter) was used as the carrier for the rhBMP-2 and ePTFE membrane was used to cover the rhBMP-2/MBCP block. The histologic and histometric parameters were used to evaluate the defects after 2- or 8-week healing period (7 animals/group/healing interval). RESULTS: The level of bone formation in the defects of both groups was significantly higher at 8 weeks than that at 2 weeks (P < 0.05). The ePTFE membrane has no additional effect compared with the rhBMP-2/MBCP block only. However, at 8 weeks, rhBMP-2/MBCP/ePTFE group showed more even bone formation on the top of the MBCP block than the rhBMP-2/MBCP group. CONCLUSION: These results suggest that the ePTFE membrane has no additive effect on bone formation when a MBCP block is used as a carrier for rhBMP-2.

Comparison of Black-pigmented Bacteroides using 16S rRNA analysis between Chronic periodontitis and Aggressive Periodontitis / 대한치주과학회지

The purpose of the research is to compare the distribution of Black-pigmented Bacteroides between Chronic Periodontitis and Aggressive Periodontitis. P. gingivalis, P. intermedia and P. nigrescens were examined in order to evaluate their distribution in patients with Chronic Periodontitis(CP) and Aggressive Periodontitis(AP). PCR and dot-blots hybridization of 16S rRNA gene were used to compare bacterial distribution of two groups - CP group and AP group, which were divided into two subgroups. Subgingival plaque taken from the diseased sites(pocket depth> or =6 mm) and healthy sites(pocket depth< or =3 mm) were grouped into the experimental group and the control group. The result are as follows ; 1. The distribution of P. gingivalis was 98.33% for chronic Periodotitis(CP), 94.17% for Aggressive Periodontitis(AP), the distribution of P. intermedia was 77.50% for CP, 64.17% for AP, and the distribution of P. nigrescens was 35.00%, 29.17%. In all 3 types of bacteria, CP group showed higher distribution compared to AP group, but only P. intermedia showed statistically significant difference. 2. In the case of CP, every type of bacteria showed higher distribution in the experimental group with statistically significant difference. 3. In the case of AP, every type of bacteria also showed higher distribution in the experimental group, but P. gingivalis and P. .intermedia showed the result with statistically significant difference, and the other did not 4. In 3 all bacteria type, N-AP showed higher distribution than N-CP without statistically significant difference These results suggest that the comparison of the distribution of Bacteroides between Chronic Periodontitis and Aggressive Periodontitis has no statistically significant difference, except P. intermedia.

The effect of newly designed toothbrush on plaque control, treatment of gingivitis and periodontitis / 대한치주과학회지

The present study investigate the effect of newly designed toothbrush(Chess tip : experimental group , conventional toothbrush(control group) on plaque control, gingivitis, and peridontitis. The results of 4weeks post-research by clinical comparison between the two groups are as follows. 1. In analysis of plaque index between groups there was significant difference in the experimental group at 2, 4 week. 2. In analysis of gingival index between groups there was significant difference in the experimental group at 1, 2, 4 week. 3. Both experimental group and control group showed decrease in periodontal pocket depth after 4week, but there was significant difference in the experimental group at 4 week. 4. Both experimental group and control group showed decrease in bleeding on probing after 4week, but there was significant difference in the experimental group at 4 week. These results indicate that newly designed toothbrush has beneficial effects as additional aid of mechanical treatment at the point of periodontal pocket, plaque control, and bleeding on probing.