• Journal of dental hygiene science
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• v.16 no.2
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• pp.176-182
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• 2016

The purpose of this study was to evaluate the in-vitro efficacy of the active ingredients of dentifrice following treatment time. The whitening effect was evaluated by a change in lightness value relative to the contact time of hydrogen peroxide, by using artificially stained hydroxyapatite discs. The anti-calculus effect was assessed based on the amount of calcium eluted from the human dental calculus by sodium pyrophosphate. Remineralization was evaluated by the Vickers hardness test following the application of sodium fluoride to bovine enamel. In order to view dentinal tubules occlusion, the formation of insoluble calcium salts by bovine dentin specimens was observed using scanning electron microscopy. Change in lightness value (${\Delta}L$) was $5.50{\pm}1.51$ after 1 min of treatment, $5.73{\pm}0.43$ after 3 min, $8.64{\pm}0.24$ after 10 min, $18.93{\pm}0.76$ after 30 min, and $27.35{\pm}0.54$ after 60 min. The amount of calcium eluted from the human dental calculus was $4.23{\pm}0.14ppm$ after 1 min of treatment, $4.51{\pm}0.04ppm$ after 3 min, $12.12{\pm}0.16ppm$ after 10 min, $17.85{\pm}0.81ppm$ after 30 min, and $25.15{\pm}0.32ppm$ after 60 min. The Vickers hardness change value (${\Delta}VHN$) was $1.96{\pm}1.44$ after 1 min, $1.52{\pm}1.06$ after 3 min, $9.06{\pm}0.15$ after 10 min, $10.83{\pm}5.13$ after 30 min, and $12.55{\pm}2.09$ after 60 min. Partial dentinal tubules occlusion was observed at 10 min and complete occlusion was evident at 60 min. In summary, the use of patch type dentifrices for 10, 30, or 60 min were 1.57 to 8.26 times more effective than using the paste type dentifrices for 1 to 3 min. Based on these findings, it is reasonable to expect that the use of patch type dentifrices for 10 min would lead to remineralization, anti-calculus and dentinal tubules occlusion effects, and that use for 30 min would result in a whitening effect.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1118-1122
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• 1996

From January 1990 through December 1995, 43 patients underwent diaphragmatic plication for the management of phrenic nerve palsy .complicating various pediatric cardiovascular surgery. Their mean age at plication was 11.1 months and sex ratio was 31 males to 12 females. In order of decreasing incidence, the primary cardiovascular procedures included modified Blalock-Taussig shunt (7), total correction for the Tetralogy of Falloff (7), arterial switch operation (6), unifocalization for the pulmonary atresia with VSD (3), modified Fontan operation (3), VSD patch closure (3) and others. The involved sides of diaphragm were right in 17, left in 2) and bilateral in 3. Extensive pericardial resection with electocauterization of resected margin was thought to be the most common cause of phrenic nerve palsy (20). The interval between primary operation and plication ranged from the day of operation to 98 days (median 11 days). The methods of plication were central pleating technique(plication with phrenic nerve branch preservation) in 41, and other technique In 2. 10 patients died after plication (7: early, 3; late), and the causes of death were thought to be unrelated to plication itself. Among the 36 early survivors, extubation or cessation of positive pressure ventilation could be accomplished between 1 and 24 days postoperatively(mean : 4.5). Cumulative follow-up was 92 patient years without major complications. Postoperative follow-up fluoroscopy was performed in 6 patients, and the location and movement of plicated diaphragms were satisfactory in 5 patients. We concluded that diaphragmatic plication with preservation of phrenic n rve branch could lead to cessation of positive pressure ventilation and complete recovery of diaphragmatic function in the long term, unless the phrenic nerve was irreversibly damaged.