endomontreal

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. 

Microendodontics case study number: 508126

Root canal procedure case study number: 29537

        509217

Source: 

  A new Dental Operative Microscope (D.O.M.) assisted root canal treatment in a calcified maxillary second molar. Case study in microendodontics number: 506317

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

Endodontic procedure problem number one to solve: Locating all four root canal entries 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 canals without loosing patency, without breaking an endodontic file and without perforating the root. 

Thus, the difficulty level of this endodontic procedure can be considered as very high. A few years back, when there was no surgical operating microscope in our dental practices and only a handfull of daring pioneers in 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. 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: Cavit ^TM.

Root canal procedure with surgical operative microscope, microendodontics case number: 156037. Pre operative film shows a large bony defect reminding us the alleged pathognomonic "J" type lesion. Still, there was no deep and narrow pocket probing. Root canals are not visible neither  in mesial or distal root.

First appointment post operative X ray dental film shows shaped and cleaned canal system with inserted intracanal calcium hydroxide. 

Post operative control X ray film in December 2011 shows a nice healing of surrounding hard tissues. Endo treatment finished on 2007 with surgical operative microscope Opmi PROergo from Carl Zeiss.This root canal therapy attempt once more enlightens the huge advantages of microendodontics and calcium hydroxide therapy in order to save teeth with an apparent very bad prognosis.

Treatment protocol:

First appointment: Opening through metal bridge abutment, gaining access to pulp chamber, adherent pulpstones and embedded pulpstones removal, root canal entries locations, cleaning and shaping, rinsing, drying, intracanal medication insertion and provisional obturation material.

Second appointment: Intracanal medication removal, rinsing and final obturation with Pulp Canal Sealer from Kerr and gutta percha

Endodontic material and equipment:

Shaping and debridment instruments: Stainless steel ISO files, Pro taper files (Dentsply) 

Rinsing solution: sodium hypochlorite 6%

Drying: sterile paper points

Calcium hydroxide 

Obturation material: gutta percha lateral and vertical condensation

Dental operative microscope: OPMI PROergo microscope from Carl Zeiss

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.  

Root canal procedure case study number: 49821617

Note on the post operative Xray dental film, the dilacerated apical curves in both vestibular roots on second maxillary molar and disto vestibular root of first maxillary molar. The values of those root canal curvature radius based on three mathematical points are all below 4 mm, these are very small radius. Thus, those cuvatures can be defined as severe. For the endodontist, choosing the right endodontic file is of the utmost importance in order to avoid damaging consequences such as: apical transportations, loss of working length, zip and perforations and fracture of instruments.

An interesting point has been raised by Drs Pruett, Clement and Carnes affiliated with the Department of Endodontics/Dental School of University of Texas Health Science Center at San Antonio:" These results indicate that, for nickel-titanium, engine-driven rotary instruments, the radius of curvature, angle of curvature, and instrument size are more important than operating speed for predicting separation".  

Much more can be learned on small curvature radius by reading the following article:  Method for determination of root curvature radius using cone beam computed tomography images                  Carlos Estrela, Mike Reis Bueno, Manoel Damiao Sousa Neto, Jesus Djalma Pécora Braz Dent J (2008) 19(2): 114-118 ISSN 0103-6440

A new Dental Operative Microscope (D.O.M.) assisted root canal treatment in a calcified maxillary molar abutment. Case study in microendodontics number: 27526

Acute pain on this maxillary molar is keeping the patient awake all night long. Pain started following a recent filling replacement.  This is an irreversible pulpitis diagnosis, patient has been referred for endodontic therapy with the help of a dental operating microscope. 

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

Endodontic procedure problem number one to solve: Exposing color map of dentin prior to locating root canal entries without perforating pulpal chamber floor 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 canals without loosing patency, without breaking an endodontic file and without perforating the root. 

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 symptomatic molar and replacing it  by an implant supported crowns would have been a good option to consider for most of us. 

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 systems. Root canals where 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: Cavit.

Last X Ray dental film is a post operative control, a crown with a perfect fit that was done by the referring dentist will warrant a good seal. 

Case study number: 497935

Patient has already been treated on an emergency basis for an acute apical periodontitis with an irreversible pulpitis on second mandibular premolar. Access opening through bridge abutment  allowed for pulpectomy and calcium hydroxide insertion at a specialist office. A provisional filling sealed the opening on occlusal. Still, as it happens often, huge leakage occurred from second bicuspid abutment margin although molar abutment was still rock hard cemented.

On pre operative Xray dental film, molar abutment shows a canal system filled with calcification and a PDL widening on its mesial root, this tooth is asymptomatic. Patient wanted to save her bridge, she understood that in order to do so, her bridge had to be removed with minimum damage in order to cement it back. By the same token, molar endodontic condition could be assessed prior to the final bridge re-cementation. 

Bicuspid bridge abutment cement has been washed out for a long time now. Existing bridge has been safely removed with minimum damage in a matter of minutes using Metalift crown and bridge removal system^TM on molar. An endodontic procedure has been performed on the bicuspid. After removal of deciduous occlusal glass ionomer filling on molar abutment, a recurrent tooth decay reaching the pulp justified a second endodontic procedure. Opmi PROergo dental operative microscope has been usefull in denticles safe  removal. Endodontic procedures have been performed using the ProTaper system endodontic files from Maillefer, root canal systems have been filled with Pulp Canal Sealer (Kerr) and gutta percha.

X ray dental film on the right shows a post endodontic outcome with existing bridge back in its original position (not cemented), that fixed prosthesis has been autoclaved and had its inner part sandblasted. Referring dentist will cement it back on abutments once he will be done with posts and cores build up of his choice. Not having to bore a large hole in the bridge abutments will definitly contribute a lot in rescuing it.

To look at a video on Metalift removing a PFM restoration please go to: http://www.metalift.com/video_downloads.html