Root Canal revision procedure on a maxillary molar which implied a plastic carrier removal as well as the by-pass of a fractured instrument previously left in the root.
On July the 29th 2009, we have been presented with this mandibular second molar. Patient was experiencing pain. This radiographic image showed a huge radiographic J-shaped lesion in the mesial aspect of the mesial root. Back then, according to some experts, this type of lesion along with a deep narrow probing was considered as a pathognomonic sign of a vertical root fracture. Since vertical root fracture has a hopeless prognosis, standards of care would have commanded its extraction. In the presence of such a periradicular tissues loss, extraction would have also been indicated in the event we were dealing with a periodontal infection.
Still, what if we were dealing we an endodontic infection? If this was the case, an endodontic revision (endodontic retreatment) would suffice to preserve this tooth. The decision of extracting or saving that tooth has been based on a foundation of sound diagnosis, as we opened the existing PFM crown to confirm the presence of a crack which we could not find.
An endodontic revision which implied an interim calcium hydroxide has proven to be the correct approach, no dental implant needed here.
The patient was experiencing a daily constant nagging pain for the last 2 months. Pain increased along with some gum swelling the during last two days. Tooth is calcified thus its root canals are narrow and the pulp chamber is filled with pulp stones. Locating narrow root canals entries can be done in an much easier way under high magnification. In such instances a dental operative microscope is mandatory.
Palatal as well as DB could easily be located after pulp stones removal with Spartan BUC One ultrasonic tip and a P5. MB1 as been located by extending the access cavity toward buccal. Under full strength microscope magnification, MB2 canal entry has been located under a 2 millimeters thick layer of sclerotic dentin.
Since a purulent exsudat was present, root canal apical preparations are large. Ca(OH)2 dressing was left in place for ten days and root canals have then been filled in a subsequent appointment.
Instrumentation has been performed with Mani stainless K files and ProTaper Universal (Dentsply). Chelator: RC Prep. PUI Irrigation: NaOCl 5%. Sealer used: Pulp Canal Sealer. Obturation technique WVC. X Ray Sensors used: CareStream Kodak 6100. Magnification OPMI PROergo (Carl Zeiss)
An intricate endodontic therapy to perform in order to preserve a very painful tooth, patient was taking 3 X 200mg Ibuprofen Pills every 3 hours in order to get through the preceding night. Serous exudate accumulation resulted in mucosa swelling.
This type of root canal treatment has a high level of difficulty because calcified canal shaping is prone to endodontic file torsional fracture inside the tooth. Calcified root canals entries where located with the help of a Carl Zeiss Microscope. These where embedded in a mass of pulpstones and calcifications which had to be removed with ultrasonic tips. Shaping performed with stainless steel K hand files 06, 08, 10, 15, 20,25, 30 from Maillefer (Envelope of motion technique and lots of chelating agent). Calcium Hydroxide Antibacterial gel insertion was mandatory to control infection within the root canal system. This gel has been removed in a subsequent appointment and replaced by a permanent root canal filling. (Cold lateral condensation gutta + Pup Canal Sealer)
First appointment procedure: Access opening, copious NaOCl 2,5% irrigation, two canal entries located by pre bending and scouting through deep main canal constriction, followed by 06,08,10,15 K files from Many. Irrigation protocol: NaOCl 2,5%, absorbent paper points + EDTA 17%, absorbent paper points, CHX 2% for 1-2mn, absorbent paper points, intracanal medication: Ca(OH)2 loaded with Barium Sulfate + Iodine (Metapaste), Teflon, Cavit. Barium sulfate displays a third canal in post operative dental X Ray film.
Patient is seen 3 weeks later, no more symptoms, scouting with pre bent 08 K file could not be of any use in locating this third canal entry neither as high magnification with coaxial Xenon light. Two previously located canals are shaped up to a 20 K file, followed by ProTaper “original” NiTi file sequence up to F3 in order to allow for ultrasonication. Adding ultrasonication to same irrigation+drying protocol, Pulp Canal Sealer and cold lateral followed by warm vertical in order to maximize the odds of “sealing” what will remain, despite all my efforts, an accessory canal.
Orthograde Root canal Retreatment ? Apical Surgery with MTA Retrofilling ? or extraction and implant? Which of these options would better serve the patient?
Distal root is short, post is long so this might impair with adequate retrofilling. Adding to this statement the event of a second distal canal and we have a recipe for a potential surgery failure. At best, this second canal might make things even more difficult for the practitioner while performing a surgery.
We also have a symptomatic tooth presenting with an apical radiolucency and a small joint on mesial, thus we can assume some leakage and this would be my second justification for an orthograde revision instead of an apico. Even though apico does give a high success rate, it will not stop coronal leakage as an orthograde approach would. (assuming a good restorative replacement)
I am also quite often engaged with such teeth, and, to my opinion, removing such a post bares less failure risks than an apico in such an area.
For those who feel uncomfortable with big casted post removal or surgery, we all agree that referral is still a better option than a sad straightforward extraction and implant. Up until now this tooth with its redone root canal treatment has been functional for 4 years and is still doing just fine.
Preserving teeth with Endodontics and Post and Core Build up.
Case Study Number 504046
“according to the current way of thinking, the most important factors against tooth fractures are the preservation of as much as possible sound tooth structure as well as the use of full coverage. The amalgam coronal-radicular dowel and core technique…has been tested successfully in recent studies, both in vitro and in vivo. Its advantages are that it requires less sound tooth structure removal, involves uniform material for both the dowel and the core, is accomplished in a single chair side session and can be easily removed. It can accordingly be used as a complete crown build up in cases where prosthetic treatment has to be postponed for various reasons.”
“This study compared the fracture resistance of coronal-radicular restorations made from three different direct restorative materials. Sixty human premolars were selected, 45 of which were root treated and decoronated. Fifteen of these premolars were restored using amalgam, 15 with composite and 15 using resin-modified glass ionomer. The 15 unrestored teeth were used as a control group… The force required to fracture each core specimen was recorded as well as the proportion of core lost due to failure. The results showed dental amalgam as having the highest fracture resistance (mean 1.93kN, sd 0.22) followed by resin-modified glass ionomer (mean 1.05kN, sd 0.20), sound tooth (mean 0.79kN, sd 0.20) and composite (mean 0.75kN, sd 0.11). The differences among all groups were significant. These results demonstrate that, although resin-modified glass ionomer is significantly weaker than amalgam, these restorations were stronger than unrestored teeth and failed at forces in excess of those encountered in normal mastication. Amalgam cores, along with resin-modified glass ionomer, tended to fail less catastrophically than the other materials and, given their strength, would remain the material of choice in situations where abnormally high forces are expected.”
A study of the fracture resistance of nyyar cores of three restorative materials. Ferrier S, Sekhon BS, Brunton PA. Oper Dent. 2008 May-Jun;33(3):305-11.
A 70 year old patient complained about mastication difficulty due to the
loss of mandibular first and second molars for many years. He wanted a fixed
prosthesis to replace his removable one but did not want implant surgery
because his thin alveolar ridge would also imply a block bone grafting.
Patient knew that he could not overcome his dental surgery fear.
Throughout his life, he never wanted to pull out his badly worn wisdom tooth
and always insisted to have it filled over and over again. It turned out in
the end, that he was right because a root canal treatment allowed for this
tooth to be preserved and used as a fixed dental bridge abutment sparing him
the need for a wisdom tooth extraction and also two more implant related
His tooth position in the arch, tooth axis inclination, calcified canals
made this root canal treatment a difficult one to perform
An intricate endodontic therapy to perform in order to preserve a very painful tooth, patient was taking 3 X 200mg Ibuprofen Pills every 3 hours in order to get through the preceding night. Serous exudate accumulation resulted in mucosa swelling
This type of root canal treatment has a high level of difficulty because debridement of those ribbonlike C shape root canals is extremely painstaking to perform.
These pictures of a “C” shaped second mandibular molar from the rootcanalanatomyprojectblogspot.com have been taken by Dr Marco Versiani. They display the complex anatomy of such a root canal system. Those pictures give a better understanding on how difficult the cleaning and filling tasks of a “C” shape root canal may be.
Calcified root canals entries where located with the help of a Carl Zeiss Microscope. These where embedded in a mass of pulpstones and calcifications which had to be removed with an ultrasonic tip. Calcium Hydroxide Antibacterial gel insertion was mandatory to control infection within the root canal system. This gel has been removed in a subsequent appointment and replaced by a permanent root canal filling. Tooth corono apical build up is an amalgam Nayyar core. A permanent crown is planned.