oral compositions for the local administration of a therapeutic agent to a periodontal pocket of a patient for alleviating dental disease comprise a plurality of dry , discrete microparticles each of which comprise an effective amount of at least one therapeutic agent dispersed in a matrix comprising a biocompatible and biodegradable polymer of preferably , the dry microparticles and dispersed into the periodontal pocket whereby upon contact with the moist environment of the pocket , they hydrate , become tacky and adhere to one another and to the tissues surrounding the pocket so as to maintain intimate contact with the involved tissue so as to induce long term therapeutic benefits .