Apex Location Method
- Apex location is a method of determining the length of the root canal of a tooth.
- The method can be done manually or with a mechanical canal instrument.
- The instrument passes a low intensity electric current through the tooth.
- The electrical characteristics of the tooth structure are measured.
- The exact position of the instrument in the tooth is determined.
Importance of Apex Location
- The apex is the tip of the tooth's root.
- The apical foramen is the opening on the apex.
- Blood vessels and nerves enter the tooth through the apical foramen.
- Different teeth have a different number of roots and apexes.
- Apex location helps in determining the depth of the root canal.
Sonada Method
- The method of Sonada measures the canals impedance using electric frequencies.
- It tracks the penetration of the instrument in the canal.
- It may be unreliable in the presence of fluid in the canal.
- Additional drying is required in such cases.
- The method provides information about the position of the instrument.
Kobayashi Method
- The method of Kobayashi calculates the ratio of the measured impedance.
- It is highly accurate even in the presence of fluid in the root canal.
- It does not provide good monitoring of the penetration before reaching the apex.
- Difficulties arise when working in a dry canal, requiring moistening.
- After measurement, the canal should be dried.
Adaptive Method
- The adaptive method of measurement is implemented by electronic apex locators.
- The device makes continuous measurements and selects a suitable method.
- In a dry canal, the device uses the method of Sonada.
- In a wet canal, the device automatically adjusts to the method of Kobayashi.
- The adaptive method is highly accurate and does not require moistening or drying the canal.
This article needs additional citations for verification. (July 2023) |
Apex location is a method of determining the length of the root canal of a tooth - manually or with a mechanical canal instrument that passes a low intensity electric current through the tooth.[citation needed]
The electrical characteristics of the tooth structure are measured and the exact position of the instrument in the tooth is determined. When the tool tip touches the top of the tooth, the instrument signals that the apical foramen is reached.[citation needed] Whenever the channel instrument is pulled out its length can be measured to determine the depth of the root canal and all other dental tools can be adjusted to this length.[citation needed]
The apex is the tip of the tooth’s root. On the apex, there is an opening called apical foramina. That is the place where all the blood vessels and nerves come inside the tooth. The apex is located on the tip of the root, or on the pointed end of it. Different teeth have a different number of roots. For example, the incisors have only one root and one apex. Teeth that have two roots have two apexes and so on.[citation needed]