endomontreal

Case study number: 461716

Patient came to our office with spontaneous intermittent pain on maxillary right side. He can readily identify the tooth, he is showing the first molar. Patient is taking many Aspirin tablets per day and is tired of suffering.

Tooth history: first attempt of root canal treatment which ended up with a broken instrument.The patient was then seen two years ago by another practitioner who succeeded in the broken instrument surgical retrieval. Even thought, at the time, a complete retreatment has been performed, the tooth remained sensitive. Since then, painful episodes became more and more frequent with a growing pain intensity. 

Tooth is sensitive to palpation with a mobility of level 2. A new crown is protecting the cusps and occlusion looks fine. Pre operative Xray shows an apical periodontitis on mesio vestibular root and something that might be a perforation with a bunch of wispy gutta percha points into it. Patient is informed of this concern prior to starting anything. Patient is informed of the high incidence rate of a fourth canal in those first maxillary molars (Studies shows up to a whopping 92% rate). He is also made aware that this fourth canal may have been omitted. After the exam, patient knows that at least two concerns have to be addressed in order to solve his problem. Implant is suggested but patient is reluctant, he is 25 years old and he wants to keep his real tooth. 

The two first X Rays are preoperative

Third X rays show the recovered MB2 with a first instrument (number 08 ISO file) reaching its apex, the fourth X ray film shows the repaired perforation with MTA and intracanal medication (Ca(OH)2 dressing) in MB2. 

Fifth image shows immediate post operative outcome with the Pulp Canal sealer overfill which has no impact on the overall prognosis. An amalgam has been placed as a long term provisional for one year. Symptoms subsided almost immediately after the intra canal dressing. The monitored tooth has been fine all along for one year. The last Xray is a one year post operative control with a brand new crown in place.

Access made through crown makes the treatment much more difficult in that the landmarks that direct the clinician to the pulp chamber are removed. Our microscope integrated video camera recorded a short movie showing treated MB2 and the MTA repair, the position of the repaired perforation site (dark grey shade) in relation to the real position of the MB2, clearly stresses out what can happen while you are looking for the MB2 with external contour of the tooth being altered by a PFM crown. 

Case study number: 434426

Patient was refered to us to locate MB2 and DB canal entries with the help of a dental operative microscope. Calcifications had to be removed with ultrasonic diamond coated tips from the pulpal chamber floor in order to expose those canal entries. 

Patient came in our office with this very well conducted root canal (Left picture). The tooth had a radiolucid kind of filling for one year and was still symptomatic. The patient was experiencing a daily constant nagging pain to an extreme severe pain during last two flights take off. Careful examination under high microscope magnification helped us in locating a very discrete purulent leakage on pulpal chamber floor in the mesio-buccal root area. After 60 minutes of intensive labor work under full strength microscope magnification the MB2 canal access has been fully exposed. It was located under a 3 millimeter thick layer of sclerotic dentin, thus well below pulpal floor level. It took another 20 minutes to clean and shape this canal to the apex. Since a purulent exsudat was present, a Ca(OH)2 dressing was left in place for ten days. The canal was then obturated with Pulp Canal Sealer and a Shilder-Yu approach for packing Gutta Percha (Picture on the right). Tooth is now completely asymptomatic.

Upper left first molar still symptomatic after root canal therapy. Dental operating microscope allowed us to locate second mesiovestibular canal (Blue arrow) under a 2 mm layer of sclerotic dentine. This canal alone took 2 hours to treat to save this tooth.

Symptomatic apical lesion on mesio vestibular root of first upper left molar. Pre operative X ray film shows a tough post to remove and a pre-existing root canal treatment performed 20 years ago. First appointment: Crown and casted post removal: MB1,P, DB retreatment and MB2 locating cleaning and shaping. Complete canal system is then filled with Ca(OH)2 and a provisionnal post and crown cemented with Temp Bond insure a good seal for the next ten days.  Second appointment : Final obturation with Pulp Canal sealer lateral and vertical packing of gutta percha One year post-op X Ray shows nice bone healing It's worth it to note that in this case, MB and MB2 apex anastomosis did not prevent this patient from getting an AAA. In first upper molars, an MB2 is present in 93% of the cases. Thus, to always strive to find, clean and shape MB2 should be the standard of care.