How the use of Opmi PROergo dental operative microscope prevented an unnecessary molar extraction. An Endodontist case study


An intricate root canal procedure. Case study number 524236

Two successive root canal procedure attemps failed on this mandibular molar. In the past three years patient had to take many courses of antibiotics to control pain and swelling. Patient is unable to chew on that tooth. An extraction and an implant supported crown has been suggested but patient wants to keep his own tooth despite all this.

Clinical examination shows vestibular swelling, probing does not show any narrow deep pocket. On radiographic examination filling material is overextended in distal root and a large bone rarefaction area is present on distal root tip. 

Retreatment of the root canal on distal root is suggested because an untreated  fourth canal is suspected. Once  filling material has been removed no extra canal could be found, instead, with the help of high magnification an apical delta or Vertucci's type V pulp space configuration could be noticed. 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 distinct foramina (1-2). According to Vertucci’s study in 1984 on a 100 mandibular molars sample, the type V configuration in distal root, occurred only in 8% of the teeth examined. 

Consequently the untreated branch is filled with necrotic pulp and bacteria releasing toxins into the surrounding bone area. An ISO files number 08 is inserted into the untreated branch, then, a NiTi file is also inserted into the retreated branch through the same canal entry and a second Xray is taken. The second Xray clearly displays the apical split in last apical third of distal single canal. Each part of the split in distal root has been individually cleaned and shaped. NiTi files allowed us to follow both curved branches. Root canals have been filled with calcium Hydroxide and patient came back 8 days later to have those filled with Pulp Canal Sealer and gutta percha. (Lateral and vertical condensation). Last (Angulated) X ray to the right shows the two branches after final obturation. 

Tooth symptoms have subsided shortly after calcium hydroxide have been inserted into the root canal system. Two months have passed and tooth is still symptoms free. Being able to get magnification and bring illumination to the root canal tip allowed for that tooth to be preserved. Patient was told to protect his tooth with cusp coverage. 

Carl Zeiss OPMI PROergo insured enough visual accuracy to prevent a missed apical split in a calcified mesial root.


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)." 

An endo retreatment with four MTA (Mineral trioxide aggregate) apical plugs helped in preserving this second mandibular molar


Case study number: 397137

Tooth history: First attempt of RCT on this mandibular second molar in 2005 did not eliminate symptoms, a second attempt in 2006 did not turned out to be any better, tooth was still having episodes of severe pain (preoperative X ray dental film taken in January 2007). Patient was told by the second practitioner to remove that tooth but she would rather try to save it for the third time. 

Patient was already aware of the tooth poor prognosis and that implant therapy would be the safest way to eliminate symptoms. Still she agreed to retreat the tooth endodontically.

During the procedure, a zip with perforation and apex blunderbuss could be noted on mesial root canals as well as in distal root canal. An apical split (with no existing apical constrictions) was also noted by probing in the distal canal. Serous exsudate was coming out of those root canals in such an amount that it could not be dried even with lots of paper points. Calcium hydroxide was inserted into the canals and patient came back 8 days later. By then symptoms had subsided. After removal of calcium hydroxide into the canals, serous exsudate was still present but in lesser amount. Another attempt with calcium hydroxide replacement was made. Patient came back, symptoms free, 2 weeks later. At this point, almost no exsudate was remaining. All canals, including apical split in distal root, were "plugged" with MTA (Mineral trioxide aggregate) under high magnification. Coronal part of the tooth was sealed with a posterior composite and no promises where made to the patient who decided not to invest in a crown considering the prognosis. This procedure has been achieved in August 2007, the X ray dental film on the right shows a 4 years post operative outcome. Even though circumscribe apical radiolucency is still present the tooth remained symptom free and functional.

In this specific case, MTA used as a root-end filling material proved so far to be effective in promoting regeneration of the original tissues when it is placed in contact with the periradicular tissues. High magnification with excellent coaxial illumination insured a better placement of this material. 

To read more about MTA applications please go to: 

Clinical applications of mineral trioxide aggregate

Mahmoud Torabinejad DMD, MSD, PhD1Corresponding Author Contact Information and Noah Chivian DDS, FICD, FAC2


1 Dr. Torabinejad is professor of Endodontics and director of Graduate Endodontics. Loma Linda University School of Dentistry, Loma Linda, CA.
2 Dr. Chivian is director of Dentistry. Newark Beth Israel Medical Center, Newark, NJ. 

A Vertucci’s type V canal configuration on a second maxillary premolar


Case study number: 473515 

OPMI PROergo from Carl Zeiss allowed us to clearly see the apical split. Each branch has been shaped, cleaned and filled with Pulp Canal Sealer and gutta percha using vertical condensation technique. 

Carl Zeiss Opmi Proergo microscope vs complete stenosis of an apical root canal split

Case study number: 487445 (calcified canals)

Clinical examination: Sinus tract, mobility: 0, deciduous amalgam restoration. 

Radiographic examination: Alveolar bone with circumscribed lucency, apical root canal split, hypertaurodontism (bull's tooth), apical root canal split branches not visible on X ray dental film, hypercementosis 

Diagnosis: pulpal necrosis with chronic periapical infection,

Etiology: marginal leakage, caries

Root canal procedure:

First appointment: gaining access to the split, locating entries, shaping and cleaning apical root canal branches inserting intracanal medication for 8 days.

Second appointment: intracanal medication retrieval, copious CHX 2% irrigation, drying canals and permanent root canal obturation with Pulp Canal Sealer and gutta percha (lateral and vertical condensation).

In that specific case, microscope was most helpful during all the following steps necessary to insure a better prognosis for this patient:

1) Locating and gaining access to buccal and lingual root canal entries (apical split was clearly visible under magnified observation) 

2) Striving to find a third branch in apical split minimizing the chances of omitting an untreated canal 

3) Aiming at the right root canal orifice when:

  • Inserting the two first endodontic files to confirm canal lengths 
  • inserting a file sequence to shape and clean each canal 
  • Positioning irrigating syringe needle tip and calcium hydroxide syringe tip toward the right canal entry 
  • Inserting absorbent paper points in both canals when drying canals 
  • Inserting master, accessory gutta percha cones and finger plugger when doing final obturation with lateral and vertical condensation  

4) Checking for pulpal tissue remnants prior to final obturation to minimise the chances of pushing them back into the apical area

Two distinct right-angled root canals exits in first molar distal root (Case 455336)

Irreversible pulpitis, deep carie, deciduous restoration, broken lingual wall. First molar with 4 root canals. Two mesial root canals no longer visible in middle and apical third with a curvature into "C" form. A file number 08 ISO follows a 90 degrees curvature in one of two distal root canals (per op. X ray dental film).

These canals in the distal root are presenting a dilaceration or sudden angular bend, according to Dr John Ide Ingle: "The major problem in these cases is the exploration, hence the pathfinder curve in the instrument". To my opinion, the main problem is the complete files sequence. These curves require much more endodontic expertise to deal with than the mesial root gradual curve.

Pulpitis irreversible, caries profunda,restauracion obsoleta(caduca, en pesimas condiciones), pared lingual fracturada(quebrada). Primer molar con 4 canales radiculares. Dos canales radiculares mesiales no visibles de lejos en tercio medio y un tercer canal radicular con una curvatura interna en forma de "C". Una lima 08 ISO  seguida con una curvatura de 90 grados en uno de los dos canales radiculares distales.

Vertucci’s type V configuration in disto vestibular root canal in maxillary molar 446826

MB1, MB2 and a very rare type V configuration in disto vestibular root canal.

Vertucci type V pulp space configuration in mandibular mesiovestibular root canal (Case 442546)

Vertucci type V pulp space configuration in maxillary second premolar (Case 439915)

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 distinct foramina (1-2). 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. Preoperative radiological findings that might help us in suspecting such a pulp space configuration: root canal abruptly becomes invisible short of the apex and not one but two areas of PDL thickening. We can see one of those two areas on top of the root apice and another one slightly below the 80 degree curved root tip. Many thanks to the refering dentist for sending me such an interesting case.

‘S’ shape canal with a Vertucci’s type V configuration in distal root

An intricate root canal procedure, case study number: 49736

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 distinct foramina (1-2). According to Vertucci’s study in 1984 on a 100 mandibular molars sample, the type V configuration in distal root, occured only in 8% of the teeth examined. In the apical third of distal root, each part of the split as been individually cleaned, shaped and filled with gutta Percha and Pulp Canal Sealer. 

Please note the bayonet shaped root canal in distal root.