• The korean journal of orthodontics
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• v.31 no.6 s.89
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• pp.601-610
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• 2001

The purpose of this retrospective study was to evaluate the level oi alveolar bone support of the erupted Permanent canine through the reconstructed cleft region compared to the contralateral canine on the non-cleft side. This study was limited to children with complete unilateral cleft lip and palate who underwent secondary alveolar iliac bone gvaft and the apices of the erupted canine roots were closed at the time of evaluation. With these criteria the study included 21 children whose average age at the time of bone graft reconstruction was 9.8 years, with a minimum of 12.4 years of age at the time of the evaluation. The study was limited to the use of iliac cancellous bone as the autograft material for reconstruction of the alveolar cleft. Cranial bone graft and other autogenous bone sources were excluded. The periapical radiographs were used to evaluate alveolar bone level of each canine. The percentages of root supported by the bone were established by dividing the amount of root covered with the bone by the anatomic root length. The canine oi the non-cleft side was used as an internal control and the canine on the cleft side was used as an experimental. There was a statistically significant difference in the alveolar bone support ratio between the control ($92.9\%$) and experimental canines ($8.7\%$). An average of $95\%$ level of alveolar bone support was achieved for the experimental canine in comparison to the control canine. Neither the presence of lateral incisor, nor the stage of root development of the canine at the time of the bone graft appeared to have affected the alveolar bone support ratio of the canine after the secondary bone graft.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.524-531
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• 2012

The objective of this study was to investigate the organic solubilization (SCOD) and improvement of methane production for pig slurry by thermal hydrolysis. A sludge cake was pretreated by thermal hydrolysis at different reaction temperatures (200, 220, 250, $270^{\circ}C$). Ultimate methane potential (Bu) was determined at several substrate and inoculum (S/I) ratios (1:9, 3:7, 5:5, 7:3 in volume ratio) by biochemical methane potential (BMP) assay for 73 days. Pig slurry SCOD were obtained with 98.4~98.9% at the reaction temperature of $200{\sim}270^{\circ}C$. Theoretical methane potentials ($B_{th}$) of thermal hydrolysates at the reaction temperature of $200^{\circ}C$, $220^{\circ}C$, $250^{\circ}C$, $270^{\circ}C$ were 0.631, 0.634, 0.705, $0.748Nm^3\;kg^{-1}-VS_{added}$, respectively. $B_u$ of $200^{\circ}C$ thermal hydrolysate were decreased from $0.197Nm^3\;kg^{-1}-VS_{added}$ to $0.111Nm^3\;kg^{-1}-VS_{added}$ with the changes of S/I ratio from 1:9 to 7:3, and also $B_u$ of different thermal hydrolysates ($220^{\circ}C$, $250^{\circ}C$, $270^{\circ}C$) showed same tendency to $B_u$ of $200^{\circ}C$ thermal hydrolysate according to the changes of S/I ratio. Anaerobic biodegradability ($B_u/B_{th}$) of $200^{\circ}C$ thermal hydrolysate at different S/I ratios was decreased from 32.2% for S/I ratio of 1:9 to 17.6% for S/I ratio of 7:3. $B_u/B_{th}$ of $220^{\circ}C$, $250^{\circ}C$, and $270^{\circ}C$ thermal hydrolysat were decreased from 36.4% to 9.6%, from 31.3% to 0.8%, and from 26.6% to 0.8%, respectively, with the S/I ratio change, respectively. In this study, the rise of thermal reaction temperature caused the decrease of anaerobic digestibility and methane production while organic materials of pig slurry were more solubilized.