BIO MECHANICAL PREPARATION IN ROOT CANAL TREATMENT.pptx

BIO MECHANICAL PREPARATION

1. BIOMECHANICAL Preparation Presented by: Dr. Archana pai I st Mds Department of Public health dentistry

2. INTRODUCTION The successful endodontic therapy depends on correct access opening followed by thorough biomechanical cleaning and a three-dimensional obturation...

3. The preparation of the root canal space involves three separate procedures: Cleaning Shaping Apical preparation These procedures are challenging and constitute a major portion of the effort in root canal treatment. In addition to the removal of the irritants, the preparation of the canal is important to ensure adequate canal obturation.

4. CLEANING / DEBRIDEMENT The cleaning refers to the removal of all contents of the root canal system before and during shaping. Organic substances, micro flora, bacterial by-products, food, caries, denticles, pulp stones, dense collagen, previous root canal filling material and dentinal fillings resulting from root canal preparation.

5. SHAPING Shaping refers to a specific cavity form with specific objectives. The shape permits vertical pluggers to fit freely within the root canal system and to generate the hydraulics required to transform and capture a maximum cushion of the gutta percha and a micro film of sealer into all foramina.

6. APICAL PREPARATION It is critical to prepare an apical matrix or barrier at proper working length.. This barrier has two functions: To serve as a stop against which to condense gutta-percha. To prevent materials, irrigants, and instruments from extruding into the periapical tissues, with resultant irritation & inflammation.

7. DEFINITION BIO MECHANICAL PREPARATION It is the attainment of free access to the apical foramen, through the root canal, by mechanical means without injuring the periapical tissue.

8. RULES FOR ROOT CANAL CLEANING AND SHAPING Direct access should be obtained along the straight lines The length of the tooth should be accurately determined Instruments should be used in a sequence of sizes with periodic recapitulation and without skipping of the sizes Instruments should be used with a quarter to half turn and withdrawn with a full stroke The barbed broaches should be used cautiously and only when the root canal is wide enough to permit their insertion and rotation without binding Instruments should be fitted with stoppers

9. PRECAUTIONS DURING INSTRUMENTATION A root canal instrument should not be forced if it binds Always only controlled finger pressure should be used in manipulating an instrument in the root canal. Always instrumentation of root canal should be done in a wet canal. Instruments must be used extravagantly particularly in the smaller sizes Once the working length of a tooth is determined, all instruments must be kept within the confines of the root canal.

10. DIFFERENT MOVEMENTS OF INSRUMENTS

11. Reaming In endodontic practice, reaming is commonly done by use of reamers , though files can also be used. It involves clockwise rotation of an instrument. The instrument may be controlled from insertion to generate a cutting effect

12. FILING The term filing indicates push-pull motion with the instrument. But this active insertion of instrument with cutting force is a combination of both resistance to bending and apically directed hand pressure. This may lead to canal ledging, perforation and other procedural errors.

13. COMBINATION OF FILING AND REAMING In this technique file is inserted with a quarter turn clockwise and apically directed pressure (i.e. reaming) and then is subsequently withdrawn (i.e. filing). File edges get engaged into dentin while insertion and breaks the loose dentin during its withdrawal. By performing this combination of reaming and filing repeatedly, canal enlargement takes place. But this technique has also shown the occurrence of frequent ledge formation, perforation and other procedural errors

14. WATCH WINDING MOTION It is back and forth oscillation of the endodontic instrument (file or reamer) right and left as it is advanced into the canal. The angle of rotation is usually 30 to 60 degrees

15. Circumferential Filing Used for canals that are larger and are not round. The file is placed in the canal and withdrawn in a directional manner sequentially against the mesial, distal, buccal and lingual walls

16. TECHNIQUES OF ROOT CANAL PREPERATION STEP BACK PREPERATION CROWN DOWN PRESSURE-LESS TECHNIQUE PROFILE SYSTEM PROTAPER SYSTEM

17. STEP BACK PREPARATION

18. ADVANTAGES It is less likely to cause periapical trauma It facilitates the removal of more debris The greater place that results from instrumentation facilitates packing of additional gutta percha cones by either the lateral or vertical condensation method The development of apical matrix or stops, prevents over filling of the root canal.

19. DISADVANTAGES The pulpal debris and bacteria may be pushed apically. Irrigation, critical part of debridement stage, cannot penetrate to the apex because of narrowness of the canals. Increased chances of errors like ledge formation

20. CROWN DOWN PRESSURE-LESS TECHNIQUE

21. ADVANTAGES Removal of coronal interference Straighter access to the apical third of the root Removal of canal contents and micro-organisms before apical preparation Increased space for instrumentation and irrigation of the apical third of the root Minimal apical extrusion of the debris

22. DISADVANTAGES Coronal portion can be over prepared and under irrigated. Could results in ledges and blockages, and with over zealous use of the files a perforation or strip may be created on the inner curve In calcified teeth, working length has to be obtained first.

23. BALANCED FORCE TECHNIQUE

24. ADVANTAGES Effective removal of debris Effective in reducing canal transportation, instrument breakage and stripping perforations Minimal apical extrusion of the debris

25. ENGINE DRIVEN PREPARATION WITH Ni-Ti INSTRUMENTS Before using these instruments, one should take care to have a straight-line access to the canal system. Canals should be thoroughly explored and passively enlarged before using rotary instrument. Instruments should be constantly moving and speed of rotation of each instrument should be known. All of these Ni-Ti rotary systems incorporate: • Crown down preparation. • Apical preparation as finale. • Increasing taper instruments

26. PROFILE SYSTEM 1. Make a straight- line access to the canal orifice. 2. Estimate the working length of the canal from preoperative radiograph. 3. Create a glide path before using orifice shapers. Establish this path with a small, flexible, stainless-steel number 15 or 20 file.

27. 4. Use orifices shapers sizes 4, 3, 2, and 1 in the coronal third of the canal. 5. Perform crown down technique using the profile instruments 6. Now determine the exact working length by inserting conventional number 15 K-file 7. After establishing the exact working length complete the crown down procedure up until this length. Use profile 25, 30 for apical preparation

28. PROTAPER FILES 1. The foremost step is gaining straight line access to the canal orifices. 2. Establish a smooth glide path before doing any instrumentation with ProTaper system. 3. Now prepare the coronal third of the canal by inserting S1 into the canal using passive pressure. Don’t go more than third fourth of the estimated canal length. 4. Irrigate and recapitulate the canal using number 10 file.

29. 5. In shorter teeth, use of Sx is recommended. 6. After this S2 is worked up to the estimated canal length. 7. Now confirm the working length using small stainless steel K- files up to size 15 by electronic apex locators and/or with radiographic confirmation. 8. Use F1, F2 and F3 (if necessary) finishing files up to established working length and complete the apical preparation. Then refine the apical preparation using corresponding stainless steel file to gauge the apical foramen and to smoothen the canal walls

30. ULTRASONIC INSTRUMENT 1. After activation, ultrasonic file is moved in the circumferential manner with push-pull stroke along the walls of canal. 2. File is activated for one minute. This procedure is repeated till the apex is prepared to at least size 25.