the Master Apical Rotary (MAR) File
TOOTH TYPE
OR GROUP FLSB MAR
References
1. Turek T, Langeland K: A light microscopic study of the efficacy of the telescopic and the Giromatic preparation of root canals, J En-dod 8:437, 1982.
2. Walia H, Brantley WA, Gerstein H: An initial investigation of bending and torsional properties of nitinol root canal files, J En-dod 14:346, 1988.
3. Kazemi RB, Stenman E, Spangberg LS: Machining efficiency and wear resistance of nickel-titanium endodontic files, Oral Surg Oral Med Oral Pathol Oral Radiol Endod 81:596, 1996.
4. Busslinger A, Sener B, Barbakow F: Effects of sodium hypochlorite on nickel-titanium Lightspeed instruments, Int Endod J 31:290, 1998.
5. Stokes OW et al: Corrosion in stainless-steel and nickel-titanium files, J Endod 25:17, 1999.
6. Mize SB et al: Effect of sterilization on cyclic fatigue of rotary nickel-titanium endodontic instruments, J Endod 24:843, 1998.
7. Canalda-Sahli C, Brau-Aguade E, Sentis-Vilalta J: The effect of sterilization on bending and torsional properties of K-files manu-factured with different metallic alloys, Int Endod J 31:48, 1998.
8. Hilt R et al: Torsional properties of stainless steel and nickel-titanium files after multiple autoclave sterilization, J Endod 26:76, 2000.
9. Zmener O, Balbachan L: Effectiveness of nickel-titanium files for preparing curved root canals, Endod Dent Traumatol 11:121,
1995.
10. Royal JR, Donnelly JC: A comparison of maintenance of canal curvature using balanced-force instrumentation with three differ-ent file types, J Endod 21:300, 1995.
11. Glossen CR et al: A comparison of root canal preparations using Ni-Ti hand, Ni-Ti engine-driven, and K-Flex endodontic instru-ments, J Endod 21:146, 1995.
12. Esposito PT, Cunningham CJ: A comparison of canal preparation with nickel-titanium and stainless steel instruments, J Endod 21:173, 1995.
13. Pertot WJ, Camps J, Damiani MG: Transportation of curved canals prepared with Canal Master U, Canal Master U NiTi, and stainless steel K-type files, Oral Surg Oral Med Oral Pathol Oral Radiol Endod 79:504, 1995.
14. Shadid DB, Nicholls Jl, Steiner JC: A comparison of curved canal transportation with balanced force versus Lightspeed, J Endod 24:651, 1998.
15. Short JA, Morgan LA, Baumgartner JC: A comparison of canal centering ability of four instrumentation techniques, J Endod 23:503, 1997.
16. Portenier 1, Lutz F, Barbakow F: Preparation of the apical part of the root canal by the Lightspeed and step-back techniques, Int En-dod J 31:103, 1998.
17. Thompson SA, Dummer PM: Shaping ability of Quantec Series 2000 rotary nickel-titanium instruments in simulated root canals:
part 1, Int Endod J 31:259, 1998.
18. Siqueira JF, jr, et al: Histological evaluation of the effectiveness of five instrumentation techniques for cleaning the apical third of
root canals, J Endod 23:499, 1997.
19. Tucker DM, Wenckus CS, Bentkover SK: Canal wall planning by engine-driven nickel-titanium instruments, compared with stainless-steel hand instrumentation, J Endod 23:170, 1997.
20. Dalton BC et al: Bacterial reduction with nickel-titanium rotary instrumentation, J Endod 24:763, 1998.
21. Shuping GB et al: Reduction of intracanal bacteria using nickel-titanium rotary instrumentation and various medications, J En-dod 26:751, 2000.
22. Glickman GN, Koch KA: Twenty-first century endodontics, JADA 131:39S, 2000.
23. Pruett JP, Clement DJ, Carnes DL: Cyclic fatigue testing of nickel-titanium endodontic instruments, J Endod 23:77, 1997.
Chapter Five Rotary Canal Preparation 89
24. Bonetti Filho I et al: Microscopic evaluation of three endodontic files pre-and postinstrumentation, J Endod 24:461, 1998.
25. Boonrat S et al: Defects in rotary nickel-titanium files after clinical use, J Endod 26:161, 2000.
26. Deitz DB et al: Effect of rotational speed on the breakage of nickel-titanium rotary files, J Endod 26:68, 2000.
27. Gabel WP et al: Effect of rotational speed on nickel-titanium file distortion, J Endod 25:752, 2000.
28. Bortnick KL, Steiman HR, Ruskin A: Comparison of nickel-titanium file distortion using electric and air-driven handpieces, J Endod 27:57, 2001.
29. Roane JB: Crown-down nickel-titanium and endodontics, Endod Pract 2:16, 1999.
30. Hinrichs RE, Walker WA, 111, Schindler WG: A comparison of amounts of apically extruded debris using handpiece-driven nickel-titanium instrument systems, J Endod 24:102, 1998.
31. Beeson TJ et al: Comparison of debris extruded apically in straight canals: conventional filing versus Profile .04 Taper series 29, J En-dod 24:18, 1998.
32. Blum JY, Machtou P, Micallef JP: Location of contact areas on ro-tary Profile instruments in relationship to the forces developed dur-ing mechanical preparation on extracted teeth, Int Endod J 32:108,1999.
33. Kanavagh D, Lumley PJ: An in vitro evaluation of canal prepara-tion using Profile .04 and .06 taper series instruments, Endod Dent Traumatol 14:16, 1998.
34. Swartz S, McSpadden JT. The Quantec rotary nickel titanium in-strumentation system, Int J Epidemiol 2:14, 1999.
9 2 Color Atlas of Endodontics
FIGURE 6-2 Left, Characteristic ultrasonic movement, showing a longitudinal motion. Right, A file set at an angle to the driver has a transverse oscillation with nodes (N) and antinodes (A).
FIGURE 6-4 A sonic handpiece.
FIGURE 6-3 Photomicrograph of an activated Mile (#20). FIGURE 6-5 The oscillation pattern of a sonic instrument. The i nitial transverse motion in air changes to a vertical action when the file contacts the root canal wall.
Sonic instruments (Figure 6-4) produce an elliptical pattern of transverse oscillation when operated in air, a pattern similar to those powered ultrasonically.
How-ever, this large transverse motion is eliminated entirely and replaced by a true longitudinal vibration of the file when the file is activated and loaded in the root canal ( Figure 6-5). 4 This longitudinal file motion may offer a superior action within the root canal.
FILE DESIGN
Different file designs are used with sonic and ultrasonic i nstruments, and different manufacturers have unique designs of files for use with endosonic instruments. The Cavi-Endo (Dentsply, York, Pennsylvania) uses small K-files (#15, #20, #25). Sonic instruments are supplied with two file types: Rispisonic and Shaper (Micro-Mega, Prodonta, Geneva, Switzerland) (Figure 6-6). These files
Chapter Six Sonics and Ultrasonics in Endodontics 9 3
FIGURE 6-6 Files used in sonic instruments. From left to right are displayed the Heliosonic file (Micro Mega Prodonta, Geneva, Switzerland) (based on a triple file), the characteristic Shaper file, and the Rispisonic file.
FIGURE 6-7 Photomicrograph showing the characteristic ridging pattern made in the canal by a K-type file. (Courtesy Dr. K.V. Krell, West Des Moines, Iowa.)
FIGURE 6-8 Cavitational activity.
have spiral blades protruding along their lengths and non-cutting tips. The Rispisonic spirals are closer to-gether than.those of the Shaper file. In addition, the Rispisonic file does not follow International Standards Organization (ISO) standards and has a thicker cross-section toward the coronal part of the file.
Although canals prepared with ultrasonics are smooth, the cutting edges of the file produce character-istic markings in a diagonal wave pattern on the canal walls (Figure 6-7). This pattern is caused by the action of the K-file flutes because the distance between the crests produced in the dentine and the cutting edges is similar.7