endomontreal

Clinical endodontic case study number: 505146 

A peculiar anatomical variation can be noticed on this mandibular first molar. What appeared to look like hypercementosis on apical aspect of distal root could in fact be a supernumerary root fused to the distal one (Radix Entomolaris). Careful removal of dentine with ultrasonic tips under high magnification of a dental operative microscope helped in locating this extra canal.  

Preoperative X ray dental film shows a "furcation defect" encompassing the entire width of the tooth (no probing). A root canal treatment implying a few Calcium Hydroxyde dressings (and being patient) helped this patient in saving what appeared to be a hopeless tooth.

Last scan shows a seven years post operative control X ray dental film. The four units fixed bridge has been cemented shortly after complete regeneration of periradicular tissues. 

Patient was told seven years ago to remove lower right premolar and replace this tooth by an implant supported crown. Lack of periradicular tissues implied a guided tissue regeneration wich, in turn implied a bone curetage close to the mental foramen. Estimated health risk: A possible permanent nerve paresthesia caused by a curetage or by an implant surgery close to the mental foramen on a patient with a narrow crestal mandibular bone. A possible failure of guided tissue regeneration wich in turn, would impair implant osseointegration (or simply make the implant surgery impossible). Clinical examination revealed a mobility level of 2 and a sinus tract. Our findings on radiographic appearance: a large but a localised bony defect and a tooth that needed a root canal retreatment. Our suggestion to the patient: To put aside the implant surgery and to invest in a root canal retreatment with a few Ca(OH)2 replacements. The patient had to be patient (and faithful) for a few months in order to monitor progressive periradicular tissue healing. Results: Per and post operative control X ray films show a progressive, then complete healing of periradicular bone tissue. In this case, root canal retreatment proved to be a safe predictable way of saving that tooth at half the cost of an agressive implant surgery. Now, 7 years later, the tooth has it’s own casted post, a PFM crown and it’s mobility level came back to zero. And above all, patient is now completely safe from any paresthesia risk.

A new Dental Operative Microscope (D.O.M.) assisted root canal treatment in a calcified maxillary lateral incisor. Case study in microendodontics number: 501812

Radiographic findings: Dystrophic calcifications in the whole canal system are completely obliterating the pulp chamber as well as the root canal itself. It can be expected that the root canal entry is completely embedded in a mass of adherent pulp stones. 

Endodontic procedure problem number one to solve: Locating root canal entry without lateraly perforating the root and without destroying to much sound tooth structure in order to keep tooth restorable.

Endodontic procedure problem number two to solve: Cleaning and shaping located root canal without loosing patency, without breaking an endodontic file and without perforating the root. 

This is an extreme endodontic procedure. A few years back, when there was no surgical operating microscope in our dental practices and only a handfull of daring (and caring)  pioneers in microendodontics trained by Dr Garry B. Carr (who is an endodontist acknowledged to me as the "father of microendodontics"), removing this tooth and replacing it  by an implant supported crown would have been a good option to consider in most instances. 

Times have changed. In order to save that tooth, calcified dentin must be carefully removed with long thin ultrasonic tips under the high magnification of dental operating microscope (OPMI PROergo from Carl Zeiss). No rapid technique exists for dealing with calcified root canal system. In this specific case ultrasonic tip went off centered creating a groove in canal toward distal, X ray dental film taken during the root canal procedure alowed us to notice this and alowed us to correct the tip orientation before making a perforation. This groove has been filled within the canal itself with Geristore from DenMat. Root canals has been shaped and  cleaned with Protaper endodontic files and 06, 08,10  K in combination with chelating agent (RC PREP). Canal system has then been filled with Pulp Canal Sealer and Gutta percha laterally and vertically condensed. Provisional filling material: ProTemp (A provisional crown with anchorage).

Last X Ray dental film is a post operative control, the referring dentist asked us to make and cement a casted post in order for him to cement a planned fixed crown. 

Case study in endodontics number: 498946

Endodontist case study of root canal procedure number: 362515

Pecora al. in 1993 reported second maxillary premolars (among 435 studied) to have one root in 90,7%. The typical maxillary second premolar may be considered having only one root with a single canal among the Caucasians (Pitt Ford, 1997). According to Vertucci's study in 1984 on 200 maxillary second premolars, in 75% of the cases, a second maxillary premolar will present with only a single canal at the apex. The type V configuration occured only in 6% of the teeth examined by Vertucci and 9% of the teeth examined by Sert (2004) 

A Vertucci type V pulp space configuration can be described as follow: One canal leaves the pulp chamber and divides short of the apex into two separate distinct canals with two distinct foramina (1-2).

Preoperative radiological findings that might help us in suspecting such a pulp space configuration: root canal abruptly becomes invisible short of the apex. 

Only one file at a time could pass through the narrower root canal part in apical third, each root canal branch has been shaped cleaned and filled individually with lateral and vertical condensation. Root canal system is having canal curvature with an s form. 

Armamentarium: OPMI PROergo dental operative microscope from Carl Zeiss, Rubber dam and rubber dam clamp and frame, Stainless steel K endodontic files, gutta percha and Pulp Canal Sealer, finger plugger.

The name comes from the letter "C" shape appearance of a very large isthmus in the pulp chamber floor when viewed from above. This isthmus or groove is the result of the merging of some or all of the root canals at the cervical area near the pulp chamber floor. Incidence is 2,7% in Caucasian and up to 13% in asian population. Pre operative X Ray dental film shows a blurred image of the canal system, canals are not visible and pulp chamber is almost not visible. Looking at these features it may not be possible to diagnose a C shape canal but we must suspect either this canal configuration or severe fibrosis/calcification.

"C" shape canals are a real challenge to preparation and may cause technical complications such as transportation, steps, stripping with perforation in the thin wall area or blockage of the canal.

This procedure requires a full understanding of this anatomy to prepare an optimal access cavity to pulp chamber through a PFM abutment,  to know where to look for the root canal entries and to be cautious about the thin wall area. This endodontic procedure also requires much more operating chair time for debridment. No rapid techniques does exist to shape clean and fill those peculiar root canal shapes. This specific endodontic procedure also justifies the use of a dental operative microscope to better see what we are doing. 

Case number 319947

This 3D video of a "C" shaped second mandibular molar from the rootcanalanatomyprojectblogspot.com displays the complex anatomy of such a root canal system. In just a few second the video gives a better understanding on how difficult the cleaning and filling tasks of a "C" shape root canal may be.  

Last september, a new generation of endodontic file has been presented at the CAE meeting in Quebec city-Canada by Dr Zvi Metzger, Professor and Chair Department of Endodontology school of Dental Medicine at Tel Aviv University. Although at the moment, the Self Adjusting File System (SAF System) is not yet readily available everywhere in Canada, this innovative endodontic file adapts to root canal shape thus, may represent in a near future, a valuable approach to more efficient debridement in C shape canals and a safer way to address thin wall section that is always present in this anatomical variation. Here is a promotional video showing how it works. 

Endodontic procedure case study number: 449927

To treat such a tooth in endodontics we needed to deal with:

• Difficult access
• Long tooth (24 mm)
• Calcified canals (root canal system with dystrophic calcifications) to locate, shape clean and fill 
• Second mesiovestibular (Mb2) to strive for with the help of a dental operative microscope
• Canal curvature with an "S" form (Bayonet shaped root canal) 

Armamentarium:

PRO Taper endodontic files from Dentsply, OPMI PROergo dental operative microscope from Carl Zeiss, Gutta Percha from META, Pulp Canal Sealer from KERR 

Case report in microendodontics number: 500047

Canal curvatures are a challenge to preparation and can be the origin of many technical complications leading to failure of treatment. Canals that curve in the mesio-distal direction are usually readily detected in radiographic dental films. However, as it is the case here, many canals curve also in the bucco lingual direction.  The bucco lingual aspect of this sharp curvature has been displayed using a mesio distal angulation of our X ray cone beam.

A new Dental Operative Microscope (D.O.M.) assisted root canal treatment in a calcified maxillary incisor. Case study in microendodontics number: 237122

Tooth is asymptomatic patient wants to replace this existing crown for esthetic purposes. Replacing this crown without doing any endo might just be the way. But after prosthesis removal, high magnification under a dental operative microscope abutment shows an horizontal crack close to the margin on its buccal aspect. Hence we do have to find a way to put a casted post in place. Creating a space for the post might create an open gate for bacteria or might disturb the microflora balance within the root canal. So what options do we have here?

Apicoectomy and a post space? Crown to length ratio on this tooth would become a problem if we had to resect last apical 4mm in order to do an apicoectomy and we cannot be certain to have obturated portal of exit with a retro prep and a retrograde filling. Not good enough to my opinion. 

Extraction with an implant surgery? The great classical solution! Why bother? BUT, patient wants to keep her own tooth and cannot invest in an implant surgery. 

Last but not least: The not yet embraced but very effective microendodontic approach. The dental operative microscope OPMI PROergo from Carl Zeiss with its magnified and coaxial Xenon illumination allowed for a great operative field observation and unequaled precise hand micro movements.  As it can be seen in the last postoperative X ray dental film, root canal procedure as been performed with no collateral damage, a casted post is planned with a brand new PFM crown by the referring dentist.