Endo Cheat Sheet Some Definitions Will White 0.15 0.45 0.90
You Yellow 0.20 0.50 0.100
Really Be Going Back? Red Blue Green Black 0.25 0.30 0.35 0.40 0.55 0.60 0.70 0.80 0.110 0.120 0.140 SSK Hand Files: all have 0.02 mm/mm increase up to 16 mm of flute w/ 0.32 mm max increase in taper Watch wind technique: turn clockwise and counterclockwise Balanced force: 1. Watch wind until stall 2. CW 90˚ to engage dentin 3. CCW 1-‐3 times w/ light apical pressure 4. CW 90˚ to load flutes with debris 5. Pull and inspect file (clean on sponge) 6. Repeat until to desired length (marked with stopper) Circumferential filing: in canal where one dimension is wider, may be necessary to flex to that dimension to smooth and shape GT series rotary Ni-‐Ti Files: each series has varied taper (.20/.10; .20/.08, .20/.06 etc); MFD is 1 mm so different length for different diameter increase: LARGE TAPER = SHORTER FILE MFD for accessory rotary file is 1.25 mm (used withOUT torque converter) After each file, IRRIGATE with NaOCl!!!! and gain patency (.08 SSK hand file) -‐ Irrigating needle stops 2 mm short of WL, if bind in canal, NaOCl can easily be forced out and harm PA tissues NO WAY TO UNDO A NAOCL ACCIDENT! Apical Control Zone: physically exists w/in roots, if taken outside à BLOW-‐OUT à post-‐op pain, irritated PA and pt; compromises healing/success 1. Retains gutta percha w/in root 2. Provides resistance form in apical region 3. Facilitates proper compaction of GP Apical Constriction: 0.5-‐1 mm short of radiographic apex (too long: blow-‐out; too short: residual debris)
Cleaning and Shaping
Must use lubricant to negotiate or blockage will result and patency will never be gained (esp if VITAL pulp)
1. ACCESS and find all canals a. See access prep tables in lab notebook b. Catch canal with endo explorer c. Start w/ #15 file then change to #8 or #10 to negotiate (esp if there is a curve) 2. Get PATENCY in all canals a. Lubricate hand file ALWAYS b. 1 mm past radiographic apex w/ #10 or 15 only c. Patency is necessary b/c canal is not clean, not under control, and apical foramen not defined until patency d. If #10 or #15 gets LOOSE resistanceàpossible curve: bend last flute to negotiate 3. Determine WORKING LENGTH a. Use #15 or larger to see on XR (10 won’t show up) b. ETL (estimated TOTAL length) on radiograph (from reference point to apex) i. white dot = 2 mm – use as key to estimate length
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c. TL (TRIAL length) = ETL – 1 mm *this is the length that you TRY in the canal i. Put #15 or #20 file 1 mm short of ETL and take XR d. Adjust TL until it is 1 mm short of the radiographic apex…this is your WORKING LENGTH! Create a GLIDE PATH a. Watchwind #20 to WL i. Clears way for rotary files (for crown down) – relieve stress so they don’t break CROWN DOWN a. .35/.12 (accessory rotary file) – MFD = 1.25 “flare” .35/.12 to flare i. No torque converter .20/.10 to begin ii. Take no deeper than length of flute or shorter if small root .20/.08 b. “.20/.10 to begin” à .20/.08 à .20/.06 à .20/.04 .20/.06 c. Take these to 4 mm short of WL .20/.04 to 4 mm short of WL d. Do not violate apical control zone! e. Use lubricant, irrigate, and find patency between each file INITIAL APICAL GAUGE a. Smallest file that will NOT pass apical constriction w/ light apical tapping (NO ROTATION!!!!) b. Open 3 files sizes i. File X is used for patency (IE: #15) ii. #(X + 1 file size larger) stops at AC (IE: #20 @ AC) à this is your IAG! *could be bigger! iii. Must remain throughout and be reproducible at completion of shaping! Determine MAF (Maximum Apical File) a. Increase 3-‐4 file sizes from IAG (IE: IAG was #20, 3 sizes bigger would be #35) b. Minimum MAF is #35 Create APICAL CONTROL ZONE (serial step back) shaping of the last 4 mm
File MAF MAF + 1 file size bigger MAF + 2 file sizes bigger MAF + 3 file sizes bigger MAF + 4 file sizes bigger MAF + 5 file sizes bigger MAF + 6 file sizes bigger MAF + 7 file sizes bigger MAF + 8 file sizes bigger
Length WL WL – 0.5 mm WL – 1 mm WL – 1.5 mm WL – 2 mm WL – 2.5 mm WL – 3 mm WL – 3.5 mm WL – 4 mm
Example #35 #40 #45 #50 #55 #60 #70 #80 #90
9. Final canal prep a. 17% EDTA 1 min to remove smear layer b. Final NaOCl rinse c. Fit master cone wet and X-‐ray
20 mm 19.5 mm 19 mm 18.5 mm 18 mm 17.5 mm 17 mm 16.5 mm 16 mm
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1 mm step back = 0.05 mm taper 0.5 mm step back = 0.10 mm taper ●
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