Abstract: In the field of dental care, diagnoses have been and being made by means of X-ray images, visual observation, explorer, palpation, fluorometery, insertion of a pocket probe and observation, observation by means of a root canal meter and the use of a Doppler flood flowmeter. However, such diagnoses are invasive and not very clear and three-dimensional X-ray CT apparatus that are being used for diagnoses are very large and complex. Additionally, OCT apparatus for obtaining optical tomographys by using reflection light that are being used by ophthalmologists give rise to problems because of the profile of the detection probe and operability when such an apparatus is used in an oral cavity that contains hard tissues such as teeth and soft tissues such as gingiva for dental care. The present invention dissolves the above identified problems and provides a non-invasive and high resolution dental optical diagnostic apparatus.

Abstract: A dental treatment apparatus having a sterilized water producing unit placed in a water circuit of a dental chair unit. The sterilized water producing unit electrolyzes water mixed with sodium chloride and hydrochloric acid in a diaphragmless electrolytic cell to produce sterilized water having a residual free chlorine concentration adjusted in the range of from 1.0 ppm to 200 ppm and a pH adjusted in the range of from 3 to 7. The dental treatment apparatus further has a water circuit switching controller that alternately switches between raw water and feed water from the sterilized water producing unit.

Abstract: A method to continuousky harden light-curable resins, by irradiating at least one shaped article made of a light-curable resin by continuously moving the article past a multiplicity of light sources while changing the flux of the irradiated light in multiple steps corresponding to the moving positions of the object and an apparatus to accomplish this method including means to continuously move the article relative to the multiple irradiation sources and means to adjust the flux density in multiple steps corresponding to the moving positions of the article. Specifically, the flux density of the light irradiated on the moving article is changed stepwide depending upon the position and the location of the article and the polymerization speed of the article and the hardening depth can be controlled in relation to its position and time.

Abstract: A method and apparatus to continuously harden articles made of visible light-curable resins, including continuously moving the articles to be hardened relative to a multiplicity of sources of visible light which are independently controllable to be able to vary the radiation to which the articles is exposed during its passage while independently controlling the temperature at which this takes place; and apparatus to accomplish this such that a large number of the objects to be irradiated passing through the hardening apparatus have the same exposure history to the visible light and to heating or cooling respectively. As the result, there is substantially no variation in the physical properties of these photo-polymerized products.