title: [Dissolution of metronidazole stilus].
abstract: Metronidazole stilus is a new preparation to be inserted into periodontal pockets for treatment of periodontitis. The certificate and file number of approval given to this new product were issued by the Ministry of Public Health in August, 1989. Its shape looks like a toothpick and the width, thickness and length are 1.5mm, 0.7mm and 3 cm, respectively. The content of metronidazole in each cm of the stilus is 2.2 mg. We have studied the dissolution of the new preparation by rotation basket method. The kinetic process of dissolution approximates first order kinetics. The K, t0.5 and t0.9 are 0.0624 min-1, 12.8 and 38.6 minutes, respectively. The requirement is that the dissolved percentage should not be lower than 60% of the added amount in 30 minutes. In order to have a dissolution test similar to that of the stilus in dental pockets, we examined the dissolution in static condition. The results showed that a very high dissolution rate appeared in the beginning, but it decreased quickly, and 71.76% of metronidazole was not dissolved until 48 hours. So one insertion per two days for clinical use is suggested.
authors.forename: T
authors.initials: T
authors.lastname: Li
authors.forename: Y
authors.initials: Y
authors.lastname: Yan
authors.forename: Y
authors.initials: Y
authors.lastname: Xiang
authors.forename: R
authors.initials: R
authors.lastname: Gu
authors.forename: L
authors.initials: L
authors.lastname: Yang
mesh_terms: D008795:Metronidazole; D012995:Solubility
chemical_list: D008795:Metronidazole