- Purpose: To clinically evaluate two types of commercial devices currently available for electronically locating the apical foramen of a root canal as an aid in determining canal length. (audible VS. meter type).
- 65 teeth with 103 canals (planned for extraction)
- Local anesthesia, RD isolation, Access, Pulpal debridement.
- WL determined using with two commercially available electronic measuring devices (Fig).
- With the lead clips of each unit attached, the file was inserted into the canal until the unit indicated that the apical foramen had been reached:
- Sono-Explorer: when a single steady tone was heard and when the needle of the meter entered the red zone and registered its highest reading.
- Endometer: this occurred when the meter read 40.
- Direct file measurements were made after teeth extraction.
- The difference between measurements obtained electrically and directly was determined as the error.
Most highlighted Results:
- Both electronic devices performed within acceptable limits in 85% (Endometer) and 89% (Sono-Explorer) of the canals tested.
- acceptable limits: a difference up to 0.2 mm from the control measurements.
- No significant difference between the two devices.
Such measuring devices have a definite place in the armamentarium of dentists engaged in endodontic therapy