Dental operating microscope assisted root canal procedure on a completely stenosed canal system.  endodontist case study number: 506712

Pre operative condition:

1. Canal is not visible on dental X ray film until last few millimeters because the root canal anatomy system does not begin before last few millimeters, this means an extremely narrow canal diameter for the practioner to locate in last apical third of root. Remaining canal diameter can be 3 times smaller than a single strand of human hair diameter. Remaining within  tooth long axis when accessing canal entry is of the utmost importance not to create a iatrogenic perforation.
2. Two previous failed attempts  to locate tooth single canal entry, this means complete loss of landmarks when looking through dental operative microscope lens to find it
3. Number 12 tooth is a 12X21 bridge abutment, this means loss of external landmarks to locate canal entry
4. Dentine shade composite completely fills up the access cavity, this means even more challenge, when drilling to expose canal entry, not to create additional tooth substance loss (thus increasing tooth weakness.

Tooth and prosthesis survival relies solely on endodontic procedure success, if canal cannot be found thus treated, tooth cannot be preserved.  

Nevertheless, a complex root canal retreatment does not have to mean extraction and replacement by a dental implant. 

Surgical operating microscopes have a steep learning curve and require training, as well as patience and practice to master. Still this piece of equipment and the learning effort it implies is well worth it since cases that once seemed impossible can now be treated with a high degree of confidence and clinical success. 

Case number: 482036

Twenty five years old patient presenting with an abscessed maxillary molar. Diagnosis: Persisting disease after root canal treatment. Etiology: untreated second mesio vestibular root canal (MB2).

Two appointments were required to preserve that tooth:

First appointment: Crown and post removals plus root canal filling retrieval, MB2 location and calcium hydroxide insertion as a medicament. 

Second appointment: Calcium hydroxide removal, irrigation, drying, final canal obturation gutta percha and Pulp Canal Sealer. Provisional filling material: Cavit.

Abutment is now symptom free and it is now all set for a casted post and permanent crown replacement.

A 6 months follow up dental Xray film shows an impressive  regeneration of periradicular tissues. Compared to its initial size, apical lesion on mesio vestibular root shrunk up to 80%. Tooth is aymptomatic and functional.

A complex root canal retreatment does not have to mean extraction and replacement by a dental implant. A research study by Farzaneh et al. on treatment outcome in endodontic found an orthograde root canal retreatment success rate of 93% . (Farzaneh M., Abitbol S., Friedman S. Treatment outcome in endodontics: The Toronto Study. Phases I and II: Orthograde retreatment. J Endod 2004; 30(9):627-633)

An endodontist case report. Microendodontics case study number: 511536

Sixty years old patient presenting with an abscessed mandibular molar. Diagnosis: Persisting disease after (25 year old) root canal treatment. A crown and two post removal where necessary in order to gain access to root canal system for retreatment. 

Only two apointments required to save that tooth:

First apointment: Crown and post removals plus root canal filling retrieval and calcium hydroxide insertion as a medicament. 

Second apointment: Calcium hydroxyde removal, irrigation, drying, final canal obturation gutta percha and Pulp Canal Sealer. Provisional filling material: Clip (not radiopaque) from Voco. 

Tooth is now symptom free and it is now ready for a post and a PFM crown.

A complex root canal retreatment does not have to mean extraction and replacement by a dental implant. A research study by Farzaneh et al. on treatment outcome in endodontic found an orthograde root canal retreatment success rate of 93% . (Farzaneh M., Abitbol S., Friedman S. Treatment outcome in endodontics: The Toronto Study. Phases I and II: Orthograde retreatment. J Endod 2004; 30(9):627-633)

 Progressive abrasion of attached pulp chamber calcifications with ultrasonic tips led to the canal entries. Required state of mind: No pushing but resolution. 

  First mandibular molar has an apical external root resorption in distal root making it difficult to obturate because of the absence of apical constrictions

   Post operative X ray dental film displaying final root canal obturation with gutta percha and Pulp Canal Sealer

 Amalgam post and core build up.

This last X ray dental film is a three years post operative control and is showing a complete regeneration of periradicular tissues, teeth are still functional and symptoms free. 

Should an implant have been put there in the first place to replace this second mandibular molar simply because this root canal procedure is extremely difficult to perform? Maybe, maybe not!

Both implant therapy and endodontics show excellent prognosis. To let the informed patient decide for himself  whether or not he want's to save his tooth instead of having a dental implant is simply common sense. 

Endodontist case study number: 197337

The recent addition of dental operative microscope (DOM) to endodontic therapy can allow better visualization and management of the intricate morphology of the root canal system during endodontic procedures through magnification and greatly improved high intensity lighting. Dental Microscope typically magnifies in the 4X to 25X range. The other commonly used magnification aide, through lens eyeglass mounted surgical telescopes, provides 2.5X to 4.5X magnification. 

We have been presented with this second mandibular molar that has only two canal entries on pulpal chamber floor. At first sight one could have easily concluded the presence of only two canals. In fact, the mesial root has a Vertucci's type 5 canal configuration. 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). Without magnification the root canal apical "split" could have been under seen, treating one branch out of two and leaving  pulp tissue inside the other branch. 

Surgical operating microscopes have a steep learning curve and require training, as well as patience and practice to master. Still this piece of equipment and the learning effort it implies is well worth it since cases that once seemed impossible can now be treated with a high degree of confidence and clinical success. 

"As the saying goes:"A picture is worth a thousand words", Click here to have a look at what can be seen at an operative field under magnified observation (10X to 25X range)." 

Microendodontics case study number: 508126

Root canal procedure case study number: 29537

Source: 

Case study in microendodontics number: 506846

Patient referred for endodontic treatment on this mandibular first molar. Coronal-radicular access was already done but canal entries are embedded in a mass of calcified dentine and could not be found.

Preoperative X ray dental film shows a complete mineralization of both mesial and distal canals coronal third. This is an intricate root canal procedure, because this pre operative condition involves dealing with complete canal stenosis caused by dystrophic calcifications. 

Dental operative microscope (Opmi Proergo from Carl Zeiss) and ultrasonic tips where most helpful in locating both mesial and distal canal entries.

Once located, our first instrument in four canals were K files number 06 (second X ray dental film). Then, mesial and distal canals have been shaped and cleaned with the Pro Taper system (Maillefer) and lots of RC PrepTM. They were subsequently filled with gutta percha (lateral and vertical condensation) and Pulp Canal Sealer EWT ^TM

Third X ray dental film (Clark's rule) shows all four treated canals. 

Amalgam corono apical core build up is shown in last post operative X ray dental film. A crown is planned by patient regular dentist.