16. Anatomic apex and Radiographic apex Anatomic apex : Is the tip or the end of the root determined morphologically, Radiographic apex : Is the tip or end of the root determined radiographically
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21. GROSSMAN’S METHOD Actual length of tooth = Actual length of instrument X radiographic length of tooth Radiographic length of instrument Actual length of tooth Actual length of instrument Radiographic length of instrument Radiographic length of tooth =
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23. 2. Subtract at least 1.0 mm “safety allowance” for possible image distortion or magnification. 3. Set the endodontic ruler at this tentative working length and adjust the stop on the instrument at that Level. 4. Place the instrument in the canal until the stop is at the plane of reference unless pain is felt.
29. Paper point evaluation Indications : Root canal with immature apex Cases in which apical constriction has been lost. Paper point evaluation, by addition of mm markings 18, 19, 20, 22, 24mm from tip and can be used to estimate working length.
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32. Electronic apex locators Connections of the electrodes To file & cheek File placed to length indicated at “zero” by apex locator Apex indication in different apex locators
43. Techniques of pulp space preparation Hybrid technique Step back step down combination procedure Apical coronal preparation technique Step back preparation & modifications. Coronal to apical preparation technique Step down tech
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47. WL established ,1 st active instr 8,10, 15 lubricated Motion- watch winding Apical preparation upto the file #25(MAF)to full WL With recapitulation using prior size
48. Stepping back in increments with recapitulation using # 25 file to ensure patency to the constriction with irrigation (step back up the canal 1mm and 1larger instr at a time)
49. For coronal and mid root preparation Gates Glidden drills Nos 2,3,4 along with lubrication
50. Return to # 25 last file (MAF) Short of working length to smooth the step back with vertical push- pull strokes (circumferential filing) H files used.
57. Step down technique Principle- coronal aspect of the root canal is prepared and cleaned before the apical part coronal preparation using gates glidden, smaller hand instruments to the apex
58. K-File Series Step-Down Technique. Starting with a No. 50 instrument (for example) and working down the canal to, say, a size No. 15, the instruments are used in a watch-winding motion until the apical constriction (or working length) is reached. When resistance is met to further penetration, the next smallest size is used. Irrigation should follow the use of each instrument and recapitulation after every other instrument. To properly enlarge the apical third, and to round out ovoid shape and lateral canal orifices, a reverse order of instruments may be used starting with a No. 20 (for example) and enlarging this region to a No. 40 or 50(for eg).