<prompt> RootZX or TriautoZX are examples of which type of apex locator:Resistance based apex locator.Multiple frequency apex locator.High-frequency apex locator.Dual frequency apex locator.  <response>: Multiple-frequency apex locator: A newer apex locator was introduced Root ZX by J. Morita, Japan that uses two wavelengths: one high 8 kHz and one low 400 Hz frequency. They assess the apical terminus by the simultaneous measurements of the impedance of two different frequencies that are used to calculate the quotient of the impedances. The other apex locators which follow the similar principle include Propex II Dentsply Maillefer;, Elements Diagnostic EAL Sybron Endo, Formatron D 10 Parkell Co. and the Apit 7 Osada. 