For undergrad BDS students

1. ROTARY SYSTEM IN ENDODONTIC
TREATMENT
Modern technique of root canal preparation
Dr K M Abdullah Al
Harun
Lecturer
Dental Unit
Sylhet MAG Osmani Medical College,

2. CONTENT
 Introduction
 History of rotary endodontic instruments
 Components of rotary system
 Endomotor
 Stainless steel hand K-files
 NiTi rotary files
 Lubricating and irrigation solutions
 Procedure
 Isolation
 Access cavity preparation
 Canal negotiation, Working length determination and glide path
preparation
 Cleaning and shaping of root canal/ Root canal preparation
 Canal obturation

3. INTRODUCION
Endodontics is the branch of dentistry concerning
dental pulp and tissues surrounding the roots of a
tooth.
“Endo” is the Greek word for “inside” and “odont” is
Greek for “tooth.”
Endodontic treatment, or root canal treatment, treats
the soft pulp tissue inside the tooth…..American Dental Association

4. INTRODUCTION
Root canal treatment (RCT) at a glance

5. INTRODUCTION
Why Rotary System?
Rotary shaping instruments are replacing the conventional hand
file systems after the introduction of NiTi files to endodontics
almost two decades ago. Advantages of this system are---
 Enables more complicated root canal systems to be shaped with
fewer procedural errors.
 Enhances the shaping ability of the canal.
 Reduces clinical mishaps like blocks, ledges, transportation and
perforation.
 Shortens the cleaning and shaping time.

6. HISTORY OF ROTARY ENDODONTIC
INSTRUMENTS

7. HISTORY OF ROTARY ENDODONTIC
INSTRUMENTS

8. COMPONENTS OF ROTARY SYSTEM
Endomotor
Generations of Motors—
 • First generation motor without torque
control.
 • Second generation motor with torque
limiter.
 • Third generation motor with simple
torque control.
 • Forth generation motor with apex
locator and torque control.

9. COMPONENTS OF ROTARY SYSTEM
Stainless steel (SS) hand K-files are
used to negotiate the root canal
initially and to maintain the patency
of the canal after use of every
cycle of NiTi file.
 #06, #08, #10, #15 and #20 SS K-files
are used for initial canal negotiation
and preparation of glide path for rotary
files.
 #10 SS K-file is used to maintain the
patency.

10. COMPONENTS OF ROTARY SYSTEM
NiTi rotary files (First introduced in 1990s)
The Nickel titanium rotary instrument systems have
2 main categories:
 Active instruments: Have active cutting
blades similar to K flexo file. They have the
ability to cut more efficiently, aggressively
and tendency to straighten the canal
curvature.
 Passive Instruments : These instruments
have a radial land between cutting edges
and flute. The radial land touches the
canal wall on its entire surface, guiding the
instrument – stable and balanced with in
the canal.
All of them having non-cutting tips to avoid
transportation.

11. COMPONENTS OF ROTARY SYSTEM
Advantage of NiTi over SS files
Nickel titanium Stainless steel
Excellent flexibility Less flexible
Conforms to canal curvature Straightens and transports canal
Plastic deformation Permanent deformation

12. COMPONENTS OF ROTARY SYSTEM
NiTi rotary files

13. COMPONENTS OF ROTARY SYSTEM
Lubricating and irrigation solutions
Objectives of irrigation:
 Mechanical & Chemical functions
 Flushing
 Lubrication
 Dissolution
 Smear layer removal
 Biological functions
 Antimicrobial

14. COMPONENTS OF ROTARY SYSTEM
Commonly used irrigating agents used in
endodontics
 Chemically Inactive Solutions
 Normal saline
 Local anaesthetic solution
 Chemically active solutions
 Main solutions:
Sodium hypochlorite (NAOCL) (0.5-5.25%)
Chlorhexidine (CHX) (0.2-2%)
 Decalcifying solutions:
17% Ethylene diamine tetra acetic acid(EDTA)
Citric acid
Hydroxy ethylidene-bisphosphonate(HEBP)
Qmix (químico MECÁNICA MIX
 Other irrigating agents : A. Hydrogen peroxide. B. Iodine based
compounds.
 Recent advances in irrigation: A. Carisolv. B. Ruddles solution. C.
Bioactive materials like bio(active) glass D. Chitosan.. E. Cetrexidine

15. PROCEDURE
Isolation with Rubber Dam

16. PROCEDURE
Access cavity
preparation
 Gain access in to the
pulp chamber using
diamond bur (Round in
special endodontic bur)
 Diamond D Bar
 Endo Access bur
 Endo Z bur
 Endo two bur

17. PROCEDURE
 After access cavity preparation a # 10 SS k
file (#06 and #08 for very narrow canal) is
introduced into the canal with watch-
winding motion.
 If the canal was calcified, deposited a small
amount of EDTA preparation in to the pulp
chamber to soften the dentin in those area.
 Irrigate the canal with NaOCl.
 Use # 15 to determine working length with
the help of Apex locator and x-ray.
 Then # 20-SS K-file.
 This step ensure sufficient space for
accommodation of NiTi rotary file in a
reproducible glide path.
Canal negotiation, Working length
determination and Glide path preparation

18. PROCEDURE
Cleaning and shaping of root canal/ Root canal
preparation with NiTi Rotaty files
The “Golden Rules” for NiTi Rotary Preparation
1. Assess case difficulty
2. Provide adequate access
3. Prepare with hand files up to size #20 prior to rotary use
4. Use light touch and low rpm
5. Proceed with crown-down sequence
6. Replace rotary instruments frequently

19. PROCEDURE
Clinical Strategies
 Access Preparation
 Straight line access is necessary prior to use
NiTi Rotary file.
 Don’t Force File
 Respect Difficult Canal Anatomy
 Don’t Overuse Files
 Avoiding Breakage Takes Practice
 Don’t Try to Bypass Ledges
 Avoid Cutting With the Entire Length of File
 Don’t Start and Stop suddenly
 Length Control is Critical
 Check Canal Patency After Every Cycle
 Use NiTi Rotary Files With Copious Irrigation
Solution
 Should be done in two phases
 Phase-i Coronal flaring
 Phase-ii Apical shaping
Cleaning and shaping of root canal/ Root canal
preparation with NiTi Rotaty files

20. PROCEDURE
Obturation