COMPARATIVE-ANALYSIS OF TETRACYCLINE-CONTAINING DENTAL GELS - POLOXAMER-BASED AND MONOGLYCERIDE-BASED FORMULATIONS

The aim of the paper was to develop tetracycline-containing formulatio ns for the treatment of periodontitis by direct periodontal intrapocke t administration. Two different semi-solid formulations were prepared, based on poly(oxyethylene)poly(oxypropylene) block copolymer (poloxam er) and monoglycerides, respectively. Both formulations possess intere sting properties as delivery systems. They are easily administered by syringe equipped with needles appropriate for intrapocket delivery, th ey are characterized by a sol-gel transition, becoming semi-solid once in the periodontal pocket and, finally, they represent biocompatible formulations eliminated from the body by normal routes. A rheological characterization of both formulations was performed in the presence or in the absence of tetracycline, determining the sol-gel transition te mperature (T-c) by 'time cure tests' and the z coefficient by 'frequen cy sweep test'. In addition, the in vitro tetracycline release from fo rmulations was determined. Comparative in vivo studies were conducted, in order (a) to compare the persistence of the gels on the gum and (b ) to evaluate the clinical performances of the gels. These latest stud ies indicated that both poloxamer and monoglycerides gels, when applie d subgingivally, produce a significantly improved outcome in moderate to deep periodontal pockets.