Preliminary study on transformation of the biological function of the cryopreserved osteoblasts cultured in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To culture and amplify the young rabbit's bone marrow stromal cells (BMSCs) in vitro, and to observe the effect of hypothermia on the cells' growing behavior and biological function.</p><p><b>METHODS</b>BMSCs were acquired from the rabbit' tibia bone marrow and induced to mature osteoblasts in vitro. The cultured cells growing well in vitro were preserved in liquid nitrogen. The anabiotic cells having cryopreserved for 1 week were chosen as the experimental group, and the routine 7th generation as the control group. Their biological function in comparion by the examination of morphological changes, cells' proliferation ability, colone forming ratio, synthesis ability of ALP and protein, mineralized nodes forming ability were observed.</p><p><b>RESULTS</b>As contrast to the control groups, the anabiotic cells also grew and proliferated well in vitro except a little more slowly than before. They had the similar general shape in all the time segments, but a little differences in cells' ultrastructure. The experimental groups also had the typical characters of mature osteoblasts, and high abilities of the synthesis of ALP and proteins. The statistic data showed that these two groups had no significant difference (P > 0.05).</p><p><b>CONCLUSION</b>The cryopreserved osteoblasts had the same biological functions and the similar growing behaviors as before. These results suggest that it is practical to use the cryopreserved osteoblasts for further study on bone tissue engineering.</p>

Clinical effect of minocycline as adjunctive therapy to scaling and root planning on treatment of chronic periodontitis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of minocycline as an adjunct to scaling and root planning (SRP) in treating chronic periodontitis.</p><p><b>METHODS</b>64 male smokers with moderate to advanced periodontitis were randomly divided into two groups: SRP alone (SRP) and SRP plus minocycline (SRP+M). All clinical parameters including plaque index (Pll), gingival index (GI), bleeding on probing (BOP), probing depth (PD) and attachment gain were recorded at baseline, 3 and 6 months after treatment.</p><p><b>RESULTS</b>According to PlI, GI and BOP, there was no significant difference between the two groups at 3 and 6 months after periodontal therapy (1 > 0.05). However, PD reduction and attachment gain were significantly greater for SRP+M than that for SRP (P < 0.05). For SRP+M and SRP groups, PD reduction were 1.98 mm and 1.32 mm, and attachment gain were 1.87 mm and 1.14 mm respectively. Deep pockets in SRP+M group showed more obvious PD reduction (3.48 mm versus 2.21 mm, P < 0.01) and attachment gain (2.62 mm versus 1.23 zmm, P < 0.01) than that in SRP group.</p><p><b>CONCLUSION</b>Treatment with SRP plus locally delivered minocycline is more effective than SRP alone in male smokers with chronic periodontitis. Mechanical debridement plus locally delivered antibiotics are recommended especially for smokers with deep pocket periodontitis.</p>