Study on the Changes of Dentinal Hypersensitivity and Surface Characteristics Following the Various Root Treatment / 대한치주과학회지

Exposure of the root surface due t o gingival recession after periodontal surgery, elicit pain response when exposed to mechanical, heat, chemical o r osmotic irritation. Especially patients treated with periodontal surgery, show high frequency. There have been reports that the 1 out of 7 patients complains of dentinal hypersensitivity. There have been many studies on the clinical effects of various materials on the treatment of dentinal hypersensitivity. The purposes of this study were to evaluate die effect of sodium chloride and potassium oxalate and to observe the relationship between the dentinal hypersensitivity and surface characteristics such as dentinal tubule size and number. This study included 20 teeth which were scheduled for extraction and had no pulpal disease. These teeth were divided into Root planing group, EDTA group, NaCl group and Oxalate group. Dentinal hypersensitivity is measured by tactile, pressured air and cold water using NRS (Numerical Rating Scales). Teeth were extracted under local anesthesia and each specimen was sectioned to a size about 3 X 5 mm and was examined under the scanning electron microscope (X2,000) The results were as follows, 1. The EDTA group exhibited significantly increased dentinal hypersensitivity comparing with the other groups. 2. The NaCl and Oxalate groups showed significantly reduced dentinal hypersensitivity comparing with the EDTA group. 3. As a method for dentinal hypersensitivity measurement, it was presumed that tactile sensitivity test was not sensitive method but air blast test and cold water test were adequate method. 4. In a SEM study, the root planing group exhibited amorphous smear layer and showed no dentinal tubule orifice, but the EDTA group showed the large number of dentinal tubules. On the other hand, the NaCl and Oxalate groups did not show exposed dentinal tubules. The NaCl group showed more rough root surface than the EDTA group, anti the Oxalate group showed many participates to be presumed as calcium oxalate particle. As the results from this study, root planing couldn't expose the dentinal tubule and NaCl and potassium oxalate occluded exposed dentinal tubule effectively. Dentinal hypersensitivity has close relationship with the exposure of dentinal tubules, especially with it's size and number.

Acute toxicity and acute skin stimulation of 250g/L potassium oxalate solution / 实用口腔医学杂志

?Objective:To study the toxicity of 250 g/L potassium oxalate solution.Methods:Acute toxicity test and acute skin stimulation test were carried out on Kunmin mice and rabbits.Results:Potassium oxalate solution at 250 g/L did not result in death of the mice even it had been administered at the dose of 10 000 mg/kg by stomach filling.The LD 50 was more than 5 475 mg/kg.The solution did not cause skin reaction in rabbits after application.Conclusion:250 g/L potassium oxalate solution is not toxic and not stimulative as a local applied drug.

ULTRASTRUCTURAL LOCALIZATION OF EPIDERMAL CALCIUM GRADIENT BY ION CAPTURE CYTOCHEMISTRY / 解剖学报

Objective To delineate the epidermal calcium ions distribution in normal and acetone-treated nude mouse skin. Methods acetone was applied on the nude mouse skin for 20*!min with cotton balls. The ion capture cytochemistry, i.e., the potassium oxalate-pyroantimonate method was employed to localize calcium ions in nude mouse epidermis for ultrastructural examination. Results Ultrastructural examinations demonstrate that abundant calcium ions displayed within the epidermis, with a low content of calcium in the basal and spinous layers, followed by a progressive increase with calcium content and reaching its maximal density within the outer stratum granulosum. Whereas, application of acetone to the nude mouse skin caused the loss of the epidermal calcium gradient.Conclusion The present results suggest that a calcium gradient exists within normal murine epidermis. Moreover, the ion capture cytochemistry is a potentially powerful investigative tool for the demonstration of epidermal ionic environment.