Cons Last Lecture

‫ممم مممم مممممم مممممم‬ Today we will talk about procedural accidents, this subject has independent chapter in the book, every thing I said –the dr. -is covered by the book except some simple clinical cases, attendance is good so I will give you the slides but for last time I wont. So lets start : What is procedural accident? It is any unforeseen circumstances that occur during root canal preparation or root canal obturation or in getting access that will affect the prognosis . Many things that could happen such as defect in placing rubber dam ,but any thing doesn’t affect the prognosis is not really important ,coz we care about things are revel ant to our work the problems may start from placing rubber dam , then getting the access , you may perforate the tooth very early in the start of root canal ,1st sometimes perforation occurs in the crown and its not very big deal , you can replace it by composite ‫مم مممم‬ You should perclay strength of the tooth and still negligible 2nd perforation some where around the chamber, means you miss direct the bur, so you should evaluate the tooth before you start, coz not all people teeth are straight , you cant easily draw triangle on the palatal surface of upper central incisor, it could be rotated so your access also will be rotated ,that means you should make sure from this, and if you are afraid from forgetting the angulation of the tooth , you could do multiple isolation which means you expose multiple teeth by your rubber dam ,how? By doing 4-5 holes in the rubber dam, so you expose and isolate from canine to canine , you see intier arch and remain oriented with angulation of tooth, now if you are drilling and you are not sure where you are drilling , what is the direction ? right or wrong direction? and you were deep specially in molars, what should you do? You can place your bur high or slow round in where you were drilling then take a radiograph and see the

angulation of the bur where it goes,mesially? Distally? Or in the direction of the roof of pulp chamber? and here you should stop. You can have a clue from radiograph about size of pulp chamber, how much you need to drill ? we said if mesial ,young between 10-25 years so he has large pulp chamber means 4 mm drilling then you will be in the roof o pulp chamber, but if he was over 50 years you need to drill 6 mm and sometimes there is no room! no pulp chamber so the roof and the floor too close on each other less than 0.5mm! So you know how mm ,you can measure it from radiograph by ruler from occlusal to the start of pulp chamber , then you get the bur down the same depth. Now we will start,1st perforation during access , 2nd cleaning and shaping , and 3rd during obturation. Now we said 1st you should study your radiograph very well, 2nd split technique for rubber dam , I will show you a picture about it , it is easy like regular rubber dam, has 4-5 holes or even 6, 3rd you can use magnification loop it is very useful for dentist , in the beginning our vision will be good then after years you cant concentrate and there will be problems in the vision, so every body should use the magnification loop coz microscope is a little bit expensive not every one can get it.. So 1st study radiograph , 2nd split technique ,3rd use magnification loops. Slide # 6 page 1: this picture multiple isolation for bleaching not for endo, see the clamp on premolar , so premolar clamp and premolar clamp and all this side is free , here we have floss connected between every 2 teeth to ensure that the rubber dam is down ,so this critical floss is for bleaching coz bleaching material irritate the gingiva but in endo we don’t need floss! We can see all the teeth, we will not forget that this tooth tilted so we need to tilt our access , so if it was tilted and I have to make it perpendicular so the access will go out, labially !!!!

Now sometimes early while we are getting our working length we start having suddenly bleeding or sever pain or when we are iirigating,the patient feels bad taste in his mouth ,so from where the sodium hypochlorite came from? if your rubber dam seals very well it means that there is a pore that sodium hypochlorite can escape to the patient mouth , a hole in the tooth , you can created a hole out side the canal . Those are indication for perforation ( bleeding , bad taste during irrigation , sever pain) 2nd thing you have to verified it ,if there is perforation even if there where bleeding out of the canal , pain , it could be remnant of pulp tissue , how could be sure? We put the file as far as it goes and Take radiograph and see if the file goes out side the root or not , centered in the canal or not. Or you can use apex locator , what is apex locator? It is a machine used to locate apex without using radiograph, its method to put the file inside the canal, and the apex locator has clip connected to the file then it will give you readings on the screen. Example: you measured your estimating working length (EWL) by radiograph and it was 23 but when you used apex locator the reading was 12 or 15 which is in the in the middle of the root , and you are sure that your measurement are correct so what does the reading from the locator means? It is perforation means it is artificial apex you created by perforation . You need to know how to confirm your perforation from 1- signs 2- symptoms of patient 3- radiograph 4- apex locator if available and im sure that all of you will bring apex locator after graduation .

Now if we had perforation how the prognosis or management would be???? Management depends on 1- site of perforation, if it is in the crown or in the root 2- size where you can repair or not or you still can go in the main canal and continue your RCT Or not. Back to the site ,1st in the crown if it was above the level of bone we replace it by glass inomer easily , or put cavity and continue the RCT then remove it ,replace it by GIC , MTA is the best but if not exists put GIC , if it was below the level of the bone it has the worst prognosis ,because there will be attachment loss, bone resorption, pocket may get infected.. and this is true in the crown or the coronal third of root canal, so in this part above the level of the bone is better in the root ,the more we get down apically we get better why? Because the more you go to the apex means that you can cleaned more of the canal and that for site, now the size, the bigger , the chance of contamination is higher so small size better , now for the time , if you detected it and discover it early you can mange it quickly before infection ,and this prognostic factor , but if someone else did it and you only discover , it will be contaminated and already we have periodontal pocket and this has worst prognosis . Now you will say it is complicated case so extract the tooth or not???? This depends on the patient , if the tooth was important ( like for RPD abutment or for bridge )so here it is critical tooth we should keep it , but if the patient has multiple extraction and elderly ( 60-70 years) we extract it. so if perforation was 1- large size 2- lead to perio pocket 3- not important to the patient , we extract it . Now we said if it was below the level of the bone “ intra bony” has worst prognosis unless it was anterior teeth and patient is young ,we do orthodontic extrusion , here the orthodontist puts bracket on the tooth it will extrude it a little bit , then we polish

the tooth so the perforation will become above the level of the bone, so we can replace the perforation easily. Crown lengthing just in perio here we contour the gingiva so can revel the perforation so we can solve the problem . So if it was 1- intra bony 2- young patient 3- anterior tooth we use : 1- orthodontic extrusion 2- crown lengthing . So if it was 1intra bony 2- young patient 3- anterior tooth we use : 1orthodontic extrusion 2- crown lengthing . The material will be 1- MTA 2- GIC sure not amalgam. Now there is something called furcation perforation , which means direct perforation in the furcation area for the roots , its advantage : accessible, you can see it directly and repair it easily specially if early discovered ,and what material you will repair ? in the past people used to repair it by amalgam but nowadays by GIC,MTA,cavit temporary until we finish the obturation then GIC or MTA, but when we place the GIC or MTA in the perforation( when we replace), how can we be sure that we are not closing the canal? We place paper point or gutta percha temporarily in the canal until we out the replacement material in the perforation . Stripping perforation, you took it third year which is perforation in the canal toward the furcation, in the danger zone , during preparation and those are difficult to be repaired coz you cant control the bleeding ,you cant negotiate the canal any more , so anyone do a perforation should ask the dispensary to give him MTA ,we stopped using privet and if there is no MTA ,there something called calcium hydroxide powder not dycal which comes in tubes ,so we pack it in the perforation . We hold it by plastic instrument and pack it by plugger or paper point or gutta percha and try to send it to the canal as much as we can but usually it has worse prognosis .

Page 2 slide #9 is picture of working length radiograph what is the radio opaque area on the tooth???? It is a crown ,and what is the problem with the crown ?? 1- it has metal ( pin as I guess) you cant see it clearly while drilling 2- the crown may change the angulation of the tooth ,so higher incidence of perforation in case of crowns. If the furcation perforation was too small we leave it and continue our endo treatment ,coz it will heals ,the bone deposits in the small hole during 6 months , any way this is under direct vision not inside the canal and you don’t know where the perforation is ?so it can be prepared not surgically by GIC,MTA. Furcation perforation :1-direct perforation 2- stripping perforation in the danger zone, and we repair it by GIC , MTA – non surgical methodIf there is 1- symptoms 2- lead to sinus track or used MTA or 3GIC and get out the furcation you will need to surgical treatment to do some recontouring or reflecting of the gum, or if it doesn’t work we cut the molar from the middle and this is what we called hemi section of one root , or bicuspbization( as I heard) for molar, and now they no longer do it ,we just extract it and implant it . Page 2 slide #11 repaired MTA if we have another tooth like this which has large apex so the largest file we have #120 can enter easily (loss) and we do irrigation by NaOCL it will easily go beyond the apex , this case happened with me ( dr.nisren)yesterday for the first time, the needle was small 27 gage entered along the canal length and by mistake entered all so the patient felt sever pain reached her eye , and came today with swilling ,she was hot “ has fever” so open apex you should be careful during irrigation ,means the depth of the needle , the 2nd concern we don’t want the gutta percha to go any where during obturation so we do apixification , create artificial step by calcium hydroxide for 3-6 months or MTA then continue your

obturation easily either conventional or injectable ,hot gutta percha by syringe no problem. Open apex : 1st concern during irrigation , 2nd concern during obturation by gutta percha. Ledge ,the most prone canals for ledge formation are : 1-long 2small 3- curved canals, so from the start you will see this type of canals from your radiograph , and when you start your endo treatment for this type you should start 1st by small files like size 8 or 10 not 15 ,then 2nd make sure not to move from size 10 to size 15 until its completely loss , then 3rd we do recapitulation ,some of you do it by master apical file which is wrong coz it is very big file so you will enlarge each time the canal and it wont be the master apical file any more ( coz it is not the largest file any more)the recapitulation should be by small file usually one size smaller than M.A.F or I ( dr.)do it by file #10 , you can also use lubricant like glyde , anyone is doing endo specially in premolar he will make a ledge !rarely for central incisor . Look at this patient he has symptoms , abscess , and crown , look at the quality of RCT ,sometimes you do it short filling or long filling and you want to use composite ,you will say ok I will skip this situation and put composite and if he had pain I will retreat him, but if the patient has appointment for crown and bridge it is unfair to do crown on like this root filling , like very short of course due to ledge and there is a space due to poor condensation or presence of second canal , and here is for presence of 2nd canal. Page 2 slide #10 this is a 2nd case which we have too short ,and under prepared ,almost here we have perforation and it get out of the root , now we decide to retreat ,how can I get the gutta percha out ???? we should talk about this subject because in the clinic we face some cases need to be retreated .so 1st gate Glidden like when we are getting our straight line access ,they should be carefully used specially in premolar ,2nd then solvent chloroform

it dissolve rubber ,coz gates glidden wick provide reservoir pool for the solvent ,how we use the solvent ?we irrigate the canal by the solvent ,leave It ,don’t make suction for the access , leave it 1 mint until become muddy ,then 3rd use headstrom file , it will engage the gutta percha and take it out , then 4th use paper point to dry and absorb the mud then irrigate and insert the file and take a radiograph to make sure that all gutta percha get out , usually it wont success from the first time , you re irrigate again until gutta percha melts and the canal becomes clean ,if there was only one void in the middle of the filling or long in the apex 1mm or short 2mm its acceptable you don’t want to re do it unless your patient complains from symptoms later on , if you make a ledge it is not easy to by pass it. How to get the gutta percha out???? 1-gates glidden 2-chloroform solvent 3- headstrom files 4 – paper points. again what is a ledge ???? Its artificial step , you missed your main canal , and we will have shorting for working length ,so you must get back for smaller file , pre care , try to negotiate the canal , if you couldn’t refer it to specialist , so if early discovered the ledge you refer it ,coz the canal is not cleaned yet , but if you made the ledge in the apical third you don’t refer it . that’s fine…. Now fractured instruments , there are a lot of instruments that fractured during working even nickel titanium that we have now in the markets they can fracture, stainless steel more prone to fracture! Why the file could fracture????? 1st - Over use of the file ,you have been using it for 10 canals ,so observe the file before using it ,look at it ,if there is unwideing for an area of the file ,the normal file is twisted in one direction so if there is any area of un twisting this is sign of fracture and it will break if you use it ….

2nd - if it was narrow don’t start with file # 20 or 25 even we say don’t use headstrom file coz it will engage and break ,and the most important thing if the a file broke and W.L= 20 and suddenly 16 so take radiograph if not a ledge so it is fractured instrument ,how I will get it out ???? either by pass it by small file or walk beside it and prepare it and get it out which needs special technique and specialist and if that doesn’t work you need to use the ultra sonic then you continue and fill the canal over it and you follow the case up, now according to the position of the fracture instrument in the canal , if it was in the apical third it has good prognosis and we consider it part of the root filling ,if it was in the middle third of the canal , and still you couldn’t clean the apical part yet, that will lead to complication for the patient see this radiograph ,you can see the radio opaque area on the mesial root on the curve ,this is fractured nickel titanium file fractured on the canal at the curve this is difficult than if it was above the curve , so you try to gain the correct length from upper mesial canal and clean as much as you can . this case see how much open apex , irrigation will easily go beyond the apex , see how much the lesion is big , and here we don’t immediately send it to surgery .no even if it is a cyst , but we use the same sequences , W.L ,endo treatment ,MTA , and continue obturation , follow up and last for 6 months to year , then you will see the bones build normally , if there was symptoms or swelling after obturation then we refer to surgery . someone asked the dr. how much MTA we will give ???? 2-3 mm try to put normal amount not much coz MTA crown more expensive than gold 1 gm costs 25 jd !!!! example if W.L= 18 and you want to put 2mm MTA , first you put 1 mm MTA and push it by the plugger and don’t enter at 18 coz by logic 18+1=19 more than the W.L so it will come out from the apex ,so you enter the plugger to 16 (16 +2=18) take radiograph you will have 2-3 radiograph during MTA placement , if there were a lot of abscess , the MTA will escape in the

abscess and this is very complicated case happened with me last year and the I opened a flap and after I opened the flap I put cavit in the root area then I back the flap ,I put the rubber dam , and I put the MTA and when I push MTA it hits the cavit and when I finished putting MTA I opened the flap removed the cavit and cleaned it , someone said that you can do implants instead of this ? this is right but not all patient can pay 300 jd for implant! Apical perforation : If you drill a lot in the canal , means that your W.L = 20 and after prepare it becomes 25 ,this is apical perforation , its al right adjust the master cone and do the obturation no problem. Over filled: if 1mm over filled its ok no problem ,more will have problems coz its sealer so 1st 24 ours will irritate and coz sensivity but after that it becomes normal ,how to avoid???? 1- make sure always from working length 2- make sure that the master cone has tug back 3- your spreader during obturation should not go to all W.L it should go shorter and if it go to the full working length leave it , change the master cone or use larger spreader 4- make sure that you are using right size accessory cone , so if the spreader enter a lot to the canal and the accessory cones enter 2-3 mm only we should go to smaller spreader . finish !!!! Dina sameir kamal

This was my 1st lecture , so I hope all of you benefit from it, it was only 32 mints and I wrote every thing the dr. said I tried my best, if you find any mistake please tell me  Enjoy reading it ,and wish me luck !

‫م ممممم ممم ممم مممم مممممم مممم مممم‬ ‫ممم مممممم م مم ممم مممم ممممم ممممم‬ ‫مممم مممم مم مممم ممم م ممم ممم ممممم‬ ‫‪ :‬ممممممم مممم ممم‬ ‫ممم مممممم م ممممم ممممم )مم ممم مممممم‬ ‫مم مممم !! ( مممم مممم ) ممممم ممممم مم‬ ‫ممممم ( م ممممم ممممم م مممم ) مممممم ممم(‬ ‫م ممممم ممممممم م ممممم م مممم م ممم‬ ‫ممممم )ممممم ممممم مممممم ( م ممم )مممم!‬ ‫ممم ممم ممم ممم مممم( م ممممم ممممم‬ ‫) ممممم( م ممممم م ممممم م ممممم مممم‬ ‫) م‪.‬ممممم( مممم مممممم م مم مممم مممم‬ ‫ممممم ممممم م ممممم ممممم م مممم‬ ‫ممممممم م ممممم م مممم مممم م مم ‪group C 2‬‬ ‫ممممم ممممم ممم م مممم م ممممم ممم ممممم‬ ‫) ممم ممم مممم مم مممم ( م مممم ممممم مم‬ ‫مم مممممم م ممممم ممممم ممممممم‬ ‫ممممممم مممممم مممم مم ممم مممم ‪......‬‬ ‫م ممممم ممم مممم م ممم مممم ممم مممممم‬ ‫‪ CONS‬مممم ممممم ممم ممم مممم مممم‬ ‫مممممم ممم ‪..   ‬‬ ‫مممم مممم ممممم مم مم ممم ممممم‬ ‫مممممممم مممم ممممممم ممم ممم مممم‬ ‫مممم مممم ممممم مممممم مم ‪... 2009 -2 -8‬مممم‬ ‫ممممم مم ممم مممم‬ ‫م مم مممم ممم ممممم ممممممم مم مممممم ‪,‬‬ ‫مممم ممم ممممممم !‬