Abstract: A composition for use in dental tissues includes hydroxyapatite having a particle size in a range from about 0.05 .mu.m to about 1.0 .mu.m. The amount of the hydroxyapatite is preferably a minimum of 0.1 percent by weight.

Abstract: An antibacterial ceramic contains an antibacterial material produced by loading an antibacterial metal such as silver on a calcium ceramic carrier and an inorganic material such as cordierite, and has a bulk density of 0.6-1.2 g/cm.sup.3. An antibacterial ceramic filter contains an antibacterial material produced by loading an antibacterial metal such as silver on a calcium ceramic carrier, an aggregate such as mullite, and a binder such as frit, and has a porosity of 20% or more. The light-weight antibacterial ceramic is suitably applicable to a roof garden or the like. The antibacterial ceramic filter can remove and extirpate various bacteria and suspensions.

Abstract: A medicine injection device capable of continuously administrating a medicine to the body of a patient over a long period of time while keeping the patient from being restrained during administration. The medicine injection device includes a medicine container and at least one medicine passage each arranged in at least one of a root and a crown, so that a medicine stored in the medicine container is administrated through the medicine passage to the body of a patient.

Abstract: A dentifrice (tooth paste) having an antibacterial effect to prevent production of carious tooth and generation of periodontal diseases such as alveolar blennorrhea. The dentifrice contains hydroxylapatite powder. The hydroxylapatite powder carries therein an antibacterial metal such as silver, copper and/or zinc. The antibacterial metal is adsorbed to and/or combined, under ion exchange, with the hydroxylapatite powder.