Root Canal Therapy on a Calcified Root Canal With an S Form Curvature. Advanced Endodontics Case Number: 525214

Root canal on calcified maxillary first premolar pre-therapy. Advanced Endodontics case number 525214-1  Root canal on calcified maxillary first premolar per-therapy. Advanced Endodontics case number 525214-1  Root canal on calcified maxillary first premolar post-therapy. Adavanced endodontics case number 525214-3

Locating both root canal entries without lateraly perforating the root and without destroying to much sound tooth structure in order to keep tooth restorable, then, cleaning and shaping those root canals without loosing patency, without breaking an endodontic file and without perforating the root represent the two major endodontic procedure problems to overcome when treating calcified canals with an S form.

Removing a tiny fractured instrument fragment from a root canal system.

Preserving teeth, pre-operative condition     (1) Mass of embedded pulp stones is still present in pulp chamber and it must be removed to increase both retention and strength of planned core (2) Big chunk of metal must be removed from mesio vestibular root canal (3) Patency must be recovered in all 3 blocked canals in order to shape, clean and fill those to the apex

Huge pulp stone removal under high magnification in order to preserve a maxillary molar


Endodontic procedure with high magnification case study number: 479527

Maxillary second left molar presenting with an acute pulpitis.

Root canal system preoperative condition: Calcified canals and a huge attached pulp stone obliterating 80% of the pulp chamber precludes any possible root canal procedure.

Procedure done under high magnification (Micro endodontics): An access cavity is made to uncover pulp stone coronal part, then a groove surrounding the attached stone is carved with a Buc 3 Ultrasonic Tip until it gets loose enough for complete removal. Unfortunately pulp stone was firmly attached to pulp chamber walls, thus, it had to be cut into pieces to allow for its removal.

Following pulp stone removal procedure, narrow calcified canals had to be located with the help of a microscope. At last, canals could then shaped, cleaned, disinfected and filled.

Opmi Proergo dental operative microscope, a cutting edge technology to save a key tooth. Overcoming an against all odds clinical pre operative condition.


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

In order to be preserved and used as an abutment for a fixed bridge replacement, this tooth must have a casted post space preparation in its coronal third. Thus apical endodontic surgery cannot be considered as the best option for the patient.


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

While being a less straightforward approach than implant therapy, this successful endodontic procedure outcome strongly suggests that, nowadays, a complex root canal retreatment does not necessarily 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. 



Pitfalls in Endodontic re-treatment on a painful Maxillary First Molar

1 Untreated calcified and contaminated canal segments

2 Hidden (thus untreated) second calcified root canal to locate and treat

3 Sargenti Paste filling material to remove













Completed root canal re-treatment procedure. Dental operative microscope and root canal re-treatment procedure case number: 448716

Calcified canals and pulp chamber filled with pulps stones, a more demanding root canal procedure











A new Dental Operative Microscope (D.O.M.) assisted root canal treatment in a calcified mandibular molar. Microendodontics case study for endodontists number: 433336

Broken lingual wall, extended deep restauration, patient has been referred for endodontic therapy with the help of a dental operating microscope because of highly calcified canals.

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

Root canal procedure is so difficult because of calcified canals that not so long ago, we would have had to remove this symptomatic tooth and replace it by an implant supported crown. Nowadays, with help of a microscope things have changed a lot.

Microscope can help us to solve Endodontic procedure problem number one: 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. 

Microscope can help us to solve Endodontic procedure problem number two: Location of root canal entries.

Endodontic procedure problem number three cannot be solved by high tech alone, only experience can help: Cleaning and shaping located root canals without loosing patency, without breaking an endodontic file and without perforating the root. 

In order to avoid implant therapy, 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 is planned by the referring dentist to prevent fracture and leakage.

Carl Zeiss OPMI PROergo dental microscope root canal procedure versus completely calcified canal

Microendodontics case study number: 514722 

Pulp canal obliteration: an endodontic diagnosis and treatment  challenge P.S. McCabe & P.M.H. Dummer International Endodontic Journal 2011

Carl Zeiss opmi PROergo microscope to locate root canal entries with calcified root canals
















Root canal procedure on calcified canals, case study number: 513546 

First preoperative X ray dental image displays a previously started root canal. This tooth was referred by a clinician who could not locate the four calcified canal entries. 

Careful removal of calcification with ultrasonic tips (BUC3) under high magnification, allowed for this root canal treatment to be completed. There is at the present time no other way than the use of a microscope to preserve such a calcified tooth. 

Root canal procedure on Radix Entomolaris presenting a severe dilaceration


Microscope in endododontics case study number 513236

We have been confronted to this three rooted mandibular first molar (Radix Molar or Radix Entomolaris), a rare anatomical variation of teeth, where a third supernumerary root is located distolingually in mandibular molars. Root canal system calcifications and a small radius root canal curvature with an "S" form made this endodontic procedure a complex one.

"The prognosis of dilacerated teeth that require endodontic treatment … is difficult to predict before treatment, and in many cases, the prognosis will not become evident until the practitioner has undertaken initial endodontic treatment to determine wether the canal can be negotiated completely and then adequately disinfected and filled."  Dilaceration: Review of an endodontic challenge  Jafarzadeh and Abbott   JOE — Volume 33, Number 9, September 2007    

In that specific case, endodontist  operative microscope was most helpful when striving to find the fourth canal entry in distal root, allowing for us not to omit the fourth deeply embedded root canal. This microendodontic case study enlightens how dental operative microscope may assist the practicing dentist into a more secure root canal procedure for his patient.

Root canal preparation and filling as been completed with stainless steel K endodontic files in conjunction with the Pro Taper system from Dentsply.

Root canal obturation as been completed with gutta percha and Pulp canal Sealer from Kerr using the Schilder-Yu condensation technique.

Pushing back the limit to save teeth with Opmi Proergo dental operative microscope. Dental operating microscope assisted root canal procedure on a completely stenosed canal system.

Endodontist (microendodontics) case study number: 44994

7 Pulp chamber and root canals are not visible on pre operating X Ray of second mandibular molar. Diffuse calcifications preclude easy canal entries location. Despite its highly calcified canals, this tooth must not be extracted, it can be saved with a dental operating microscope assisted root canal procedure. 

 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.