Toei Electric Co., Ltd.

The Yoshida Dental Mfg. Co., Ltd.

Shigeru Shoji

Masahiro Otsuka

Kazuaki Hara

Hiroshi Horiuchi

Root apex position model data associated with electrical characteristic values between a measurement electrode and a mouth electrode in a state in which the distal end of the measurement electrode is located at a root apex position of a root canal is stored in a storage unit. A power supply applies measurement signals of 500 Hz and 2 kHz between the measurement electrode and the mouth electrode. Two different current values flowing between the measurement electrode and the mouth electrode are detected. These current values are compared with the root apex position mode data stored in the storage unit. If the root apex position data includes any data which coincides with the current values, it is detected that the distal end of the measurement electrode is located at the root apex position.

Root apex position detection apparatus

A tooth mobility measuring apparatus of this invention includes an impact mechanism which injects or sucks a fluid to apply an impact to a tooth, a sensor which detects the displacement state of the tooth which is moved by the impact force from the impact mechanism, and a tooth mobility calculation mechanism which calculates the tooth mobility of the tooth on the basis of the output signal from the sensor. The displacement state of the tooth is measured without touching the tooth.

Tooth mobility measuring apparatus

A laser cutting apparatus is disclosed which includes a laser emitter capable of outputting a laser beam in pulses, a laser beam irradiation member, and a dental-crown polishing and washing member. The dental-crown polishing and washing member has an injection member through which air, water and polishing material are output toward a laser-beam-irradiated surface. A control member is provided which is capable of controlling the operation of laser emitter and dental-crown polishing and washing member. The laser beam irradiation member and injection member are combined with each other by means of an adapter disposed therebetween, thereby enabling both of laser beam irradiation member and injection member to be held and operated by a single hand. By employing this laser cutting apparatus, a high-energy laser beam can be used in the medical and dental fields for removing soft dentin to form a cavity. This apparatus does not have problems due to irradiation of a high-energy laser beam, such as the production and residue of a carbonized layer in the dentin, formation of a fused layer in the dentin, occurrence of a cavity margin having an irregular configuration, and cracking and damaging of the dental pulp attributed to a temperature rise.

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Sendai, Japan

Shigeru Shoji