| 摘要 |
A dental paralleling system in which a Hall Effect sensor is carried by a dental handpiece and magnet is detachably fastened to a patient's set of teeth and so oriented that the lines of force in the magnetic field are parallel to the cutting axes of converging or non-converging base surfaces and cylindrical bores to be prepared in one or more of the set of teeth. During cutting of the base surfaces or drilling of the bores, the Hall Effect sensor is positioned within the field of the magnet. Control means responsive to a Hall Effect potential condition detected in the sensor generates an audible or visible (or both) signal enabling the dentist to guide the cutting tool up and down and from side to side while the Hall Effect sensor remains positioned at some location within the magnetic field and aligned with the magnetic lines of force which are substantially parallel throughout a range of positions enabling the cutting tool to be used on opposite sides of a tooth or on different teeth in the set. By manipulating the dental handpiece to maintain the Hall Effect sensor aligned with these lines of force in response to the signal or signals during the cutting or drilling procedure, the axis of the rotary cutting tool can thereby be kept parallel with these lines of force enabling the dentist to prepare base surfaces on the sides of the teeth which either are parallel or converge in a precisely controlled manner, as desired, for positively supporting crowns and bridges, and enabling the dentist to drill precisely parallel cylindrical bores for receiving supporting pins. |
