The invention provides a composition containing particulate calcium carbonate composed of primary particles which are scalenohedral and which have an average size of 2 microns or less； for the treatment of hypersensitivity arising in natural human teeth by application of the composition thereto. The scalenohedral calcium carbonate particles are effective as dentinal tubule occluding agents. Furthermore they can provide a smooth and pleasant mouth- feel when formulated into products such as dentifrices. They may also play a dual role of desensitizer and gentle tooth whitener, when incorporated into a dentifrice product form.
