An apical foramen locator that a dental or medical practitioner can use to
quickly and accurately identify the location of a patient's apical foramen
during a dental/medical procedure is provided. The apical foramen locator
determines the location of the apical foramen relative to a tool inserted
into the patient's tooth by sensing an impedance--typically the voltage
across two electrodes--and a stimulus voltage, and retrieving from an
impedance map apical foramen location data that corresponds to the sensed
impedance. The apical foramen locator can include a power circuit operable
to apply a stimulus voltage across two electrodes and a reference
resistor, an impedance-sensing circuit operable to read the stimulus
voltage, a first voltage across the electrodes and a second voltage across
the reference resistor and a processing component operable to derive first
and second voltage indices from the stimulus, first and second voltages.
Impedance maps can be generated using the apical foramen locator on
reference teeth and can be stored in a memory used by the processing
component.
