Elimination of Elyzol® 25% Dentalgel matrix from periodontal pockets

Abstract Elyzo® 25% Dentalgel (EDG) which is developed for use in the treatment of periodontitis is a suspension of metronidazole benzoate (40%) in a mixture of glyceryl monooleate (GMO) and triglyceride (sesame oil). Metronidazole can be detected in the periodontal pockets 24–36 h after application. The aim of the present study was to estimate the period of time that the gel matrix persists on periodontal pockets after 1 application of EDG. 12 patients were included in the study. From each patient, 1 sample was taken before and immeditely after, and 1, 2, 3, 4, 5, 6, 8, 12 and 24 h after application. Subgingival scaling followed by absorption of gingival crevicular fluid with filter paper was used for sampling. The sampling unit was 1 tooth. Each sample was assayed for the amount of GMO and oleic acid (a degradation product of GMO) by means of high‐performance liquid chromatography (HPLC) with UV detection. To allow determination of the GMO dose applied into the pockets and to estimate the recovery rate of the sampling method, 1 tooth in each patient was selected for sampling as soon as the gel had set, i.e., about 10 min after application. Only in 1 patient was a detectable amount of GMO within the pocket revealed 24 h after application. This amount was approximately 0.5% of the mean GMO dose applied around 1 tooth. GMO was found no longer than 12 h in the remaining patients.