lec 1 introduction to endodontics
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Introduction To Endodontics Mona Marashdeh Tasneem & Hana'a Sun. 10-2-2013
Introduction To Endodontics Endodontic Instruments Endodontics is the specialty of dentistry that manages the prevention, diagnosis, and treatment of the dental pulp and the periradicular tissues that surround the root of the tooth. "Endo" is the Greek word ="inside "odont" is Greek ="tooth". Endodontic treatment =treats the inside of the tooth. *The pulp is located Inside the tooth, under enamel and dentin. *The pulp Extends from the crown of the tooth to the tip of the roots where it connects to the tissues surrounding the root. *It Contains blood vessels, nerves and connective tissue .
* The pulp Creates the surrounding hard tissues of the tooth during development . * The pulp is important during a tooths growth and development. * Once a tooth is fully mature it can survive without the pulp, because the tooth continues to be nourished by the tissues surrounding it.(Mean when the
tooth is fully mature ,no problem to do root canal, it can survive without the pulp bcz of reason mentioned above)
*The objectives of Endodontic Treatment : -To relief the pain (to make the patient symptom free). - To render the affected tooth biologically acceptable and functioning without a diagnosable pathosis - Removal of pulp from root(s) of tooth - Disinfections of root and surrounding bone - The Root canal treatment is an attempt to retain a tooth which may otherwise require extraction. ** The Indicationes For Endodontic Therapy : 1. Teeth with pulpal and /or priapical pathosis 2. Teeth with no pulpal or periapical pathosis may need endodontic treatment due to: The need for post and core construction to rebuild the missing coronal portion of the tooth Traumatic pulp exposure due to dental work or accidental fracture. Esthetic requirement
*** Contraindications for Endodontic Therapy :1-Teeth with insufficient periodontal support. (If the teeth is periodontal invoved with bone loss ,the extraction is better than Root Canal treatment. 2-Teeth with vertical root fracture.(Also for extraction) 3-Non restorable teeth which can not properly function after endodontic treatment. 4-Non strategic teeth which can not serve in occlusion or as abutments after endodontic treatment.
- Phases of Endodontics treatment : Diagnostic phase : you have to make agood diagnosis to know if the tooth need root canal treatment or not ,then Preparatory phase include access cavity,cleaning and shaking then Obturation phase
(1) (2) (3) (4) (5) (6)
In this phase you have to diagnose the condition of tooth and determined the plan of treatment You have to do radiography exam,clinical examination to make agood diagnosis so we need akit for examination for endodontic. The kit of examination include : a front surface mouth mirror a periodontal probe an explorer spoon excavator the Glick No. 1 instrument cotton forceps
*Endodontic Explorer ,it is different from that we used in CONS Lab. * Explorers are double-ended instruments with long tapered tines at either a right or an obtuse angle.
* This design facilitates the location of canal orifices
* They are very stiff and should not be inserted into canals or used for condensing gutta-percha *Dont heat it. We use Explorer for diagnosis to locate the canal only .
The same to what we use in the CONS Lab . The excavator is used to remove caries, deep temporary cement, or coronal pulp tissue. The endodontic excavator has a right or left orientation Also you shouldnt heat the exvator to cut the gutta percha ,only we heat the plugger .
*Not nessary but it is good to have it . * 2 tips: One tip (Plugger for cutting and condensation of gutta percha and the paddle tip looks like plastic instrument for putting the temporary filling.
_The second phase of the endodontic after you did agood diagnosis and the tooth need root canal treatment is the
- We do the treatment ,open the access cavity and we do the cleaning and shaping. - (In this lecture we not go to talk about the steps of shaping and cleaning ). - During this phase the condition of the tooth is determined and the plan of treatment is developed. - Instruments used for access and cleaning and shaping include : (1)hand pieces (slow and high speed) High speed to enter through the enamel and slow speed through the dentine. (2) burs (slow and high speed burs ) (3)rubber dam ,after we open the access cavity of tooth ,we put the rubber dam ,sometimes if the access is simple we can put the rubber dam before the access but usually we open the access and before instrumination we have to put the rubber dam . (4)We need a special syringe called Luer-Lok syringe with a 27-gauge needle to do irrigation . (5) We need locking cotton pliers (6) rotary instruments (Gates-Glidden drills) (7) a plastic instrument (Glick No. 1) for temporary placement (8) broaches and files (9) a lentulo spiral drill (10)Endodontic ruler or a millimeter ruler to measure the length of the file.
*This is the rubber dam ,we use it to isolate the tooth from the saliva ,you cant root canal without putting rubber dam .
(In the lab you will not put the rubber dam but you have to learn how to put it ).
*This is the rubber dam kit and it concerned the rubber dam sheets (green sheets). *This is the Punchior ,we make the punchior inside the rubber sheets.And this is the foreceps ,this is the frame ,it can be metal frame or plastic frame .we can see also the Clamos in different sizes and shapes for different teeth (Anterior or Posterior ,right or left ,and Molar or Premolar ). *This is the rubber dam kit (Forceps, Punchior,Frame,Rubber dam sheets and Clamps).
with different gauges.
*look to the tip ,this is safety tip ,the opening from the side not from the tip,dont allow the irrigants to go outside the apex .In the other side we use standard syringe bcz we are not using the sodium hypochloride irrigants (this is safety tip syringe).
* The nomenclature follows the recommendations of the International Organization for Standardization (ISO): 1. Hand-operated include K-type reamers and files, broaches, and Hedstrom-type files. 2. Engine-driven are hand types that have a latch that inserts into a slow-speed handpiece. These include rotary (GatesGlidden and Peeso) engine-driven reamers and files and reciprocating files or reamers.
3. Ultrasonic and sonic are diverse in design. 4. Nickel-titanium is a cross-over design and has been adapted both for hand instruments and rotary applications
To debride a region of the canal space completely, the instrument must contact and plane all walls. Despite continual improvements in design and physical properties, there are still no instruments that totally clean and shape all root canal spaces. Stainless steel instruments are relatively inflexible, which renders them not particularly adaptable to canal curvatures. (Mean if you have acurve canal it is difficult to use the stainless steel file) Nickel-titanium instruments are more flexible and adapt more readily to fine, curved canals but have no advantage over stainless steel files in irregular canal spaces.(Mean the canal not round ,(it is Oval ) ,no one file can clean the canal walls ,you have to cross the file against all wall bcz the shape of the canal is oval .
A hand-operated reamer or file begins as a round wire that is modified to form a tapered instrument with cutting edges. The instrument is used with a twisting (reaming ,rotation ) or pulling (filing , push out side ) motion in an attempt to produce clean, smooth, symmetrical canal walls. *Several cross-sectional shapes of files are commercially available
The FIRST File is flex and we not use it . The SECOND File is that we are using . The cross section is square in small files and rhomboid with large files . The fourth File is the H-File
* Two techniques for manufacturing these instruments have been developed: 1- Machined 2- Ground Twisted
Machined:- One technique involves machining (grinding) the instrument directly on a lathe(They dont do twistint to file ,the wire was square ,they do grinding). - H-File (Hedstrom file is machined ,we will not use it ). - All the nickel-titanium instruments are machined. - Sometimes K-type files which is ground twisted ,they do machined to them and the properties of them become different . - This change from the grinding and twisting manufacturing process results in different physical and working properties from the original K-type file - The machined file has less rotational resistance to breakage than a ground-twisted file of the same size.(Mean when we used the machined file for twisting ,it can break )
- H-Files ,we cant use it for reaming or twisting ,they are used only for filling(pulling) motion,they are liable to fracture for that H-files not use for treatment ,they are only used for retreatment bcz the cutting edges sharpe ,so it is useful to remove thr gutta percha in retreatment ,but in treatment we use the K-files bcz they are flexible ,we can do reaming and filling . - H- file only used for filling (pulling)motion.
The Ground twisted (The second way of manufacturing)Another technique consists of first grinding, then twisting. Raw wire is ground into tapered geometric blanks: square, triangular, and rhomboid with different cross section according to the type of the file, as we said the small K-files are square cross section ,and the large K-files are rhomboid (They do grinding accordint to the shape then twisting) The blanks are then twisted counterclockwise to produce helical cutting edges. These are K-type files and reamers(the number of flutes in the files are more than in the rreamers and the number of twisting for files more than reamers). K-files have mor