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Dentistry/pain in tooth after root canal treatment


QUESTION: Dear Dr. Finnk

    My # 14 had a root canal procedure but stayed extremely
painful for about ten days. On re-examination my dentist
adjusted occlusion and explained about ligaments,etc.
However a lesser pain persists. Re-examination disclosed no
cause. The pain persists to this day (3 years later) I seem
to be condemned to a life time of tooth ache, when I thought
the whole point of the expensive procedure ($1250 initial, then abt. $ 300 in re-exam fees !) was to get rid of that.
My uneducated guess is a small side channel was missed.
But what to do and who pays if re-treatment is needed ?

Thank you in advance for your advice.

Most sincerely,

Eyck Bernardy

ANSWER: Dear Eyck,

Bingo!  You may have a small canal that was not completed.  Or you may be a tooth clencher, in which case you may have to suffer a small amount of pain due to your clenching habit.  Or the bite may still be high, and the tooth may need adjusting.  Or you are having a reaction to the root canal filling material.  Or you may be having phantom pain.  Or you may be having a combination of any or all the above.

Sometimes an excellent xray will show the problem.  Sometimes not.  I wish I could help you more.  You may wish to contact an endodontist (a dentist who specializes in root canals) if you want more information.

---------- FOLLOW-UP ----------

QUESTION: Dear Dr. Finnk,

First, let me thank you for your very prompt and knowledgeable answer, but, I really doubt I have a combination of all the above. That's just too complicated.

Yet some combination seems possible to me. I do suffer from broxism, but
since occlusion was adjusted on three separate occasions would the tooth still be high? My dentist was very painstaking, especially the last time. He wanted that to be his answer - not a re-do.

An adverse reaction to the filling material is also unlikely since another tooth received the same material earlier w/o problems, unless
he's changed the filling material since...

But what appears to buttress the 'missed channel hypothesis' is a
sugar sensitivity,( indicating some access leakage? ).
Still, this office has nearly state of the art x-ray capability and nothing shows up. Can an endodontist really do much better ? Or should
I resign myself to the pain ? What is the tooth prognosis with a live
(though irritated nerve) ?

Suppose a missed channel is discovered, who do you feel should in fairness pay for any re -treatment ? I have no dental coverage and
I've already paid $ 1550.

Thank you again !

Eyck Bernardy

ANSWER: Your question is a good one.

The sugar sensitivity indicates that there is a live nerve in a tooth that is being exposed to saliva.  The dentist will need to test the teeth to make sure that the sweet sensitivity is coming from the tooth that had the root canal, or is coming from another tooth.  It is far more likely that the sweet sensitivity is coming from another tooth.

If the teeth are tested, and the root canal tooth is sensitive to sweet, that would indicate live nerve tissue in the tooth.  I cannot predict or assess what your dentist might charge to remake this root canal.  In my office, if a recent root canal does not perform as expected, and I decide to remake the root canal, I would not charge the patient.

However, my usual protocol for a root canal that I did, that is giving the patient problems that I cannot resolve prior to re-treat, is to send the patient to a root canal specialist.  If the specialist determines that my root canal requires re-treatment,  I will refund my fee to the patient, and let the specialist collect his fee from the patient.

This is not to say that every dentist does what I do.

---------- FOLLOW-UP ----------

QUESTION: Dear Dr. Finnk,

I may be stretching things by asking yet another follow up, but
your answer may make an important decision easier, so would you please
bear with me?

Can you tell me what, in general, a tooth prognosis is for an
incompletely treated tooth, that is a tooth with its main channels
properly treated, but with an overlooked (live) minor channel?

Will the remaining nerve simply get on, or will it likely die and become
infected with subsequent complications? Or will it die and, since isolated
not likely become infected. Or is this simply a "who knows..." ?

Since gutta-percha  may contain a bacteriostat, perhaps this is what has
been irritating and slowly killing the remaining nerve. The pain is gradually ebbing (from an initial high of about 8 to around 3).

And I promise I'll not pester you about this (x!//!!xx) tooth any more
after this - you've just been great !

Thank you again !

Eyck Bernardy

If the tooth is slowly getting better, let it slowly get better.  Stop being concerned with what's inside.  Because if it is an accessory canal (most molars have accessory canals which can never be reached by current endodontic techniques), and your root canal was well done, these canals usually die out and do not cause trouble for many years, if ever.

Back when I was learning to do root canals, our protocol was to open the tooth, open the known canals, clean with hypochlorite (a powerful disinfectant like chlorine bleach), dry the canals, then dip a small cotton pellet into Formalin or Creosote or Camphorated Phenol, and place it into the tooth and seal it with temporary filling for at least 2 days.  These are very powerful disinfectants that vaporize and kill every living thing inside the tooth, including accessory canals. And that was back before we know how many tiny canals there could be in the root complex.

Like most things that worked well in the good old days, these excellent disinfectants have since been banned for use in humans, as they were deemed too toxic.  It is my belief that this is one reason there are now more complications and more failures with root canals.

If you are still experiencing sweet sensitivity, this should be checked out.  It usually indicates tooth decay or a leaky filling that needs replacement.  And let me repeat my opening statement:

If the root canal tooth is slowly getting better, let it slowly get better.  Stop being concerned with what's inside.


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Howard Finnk, D.D.S., P.A., CEO


I am a Family, Implant and Cosmetic dentist. I will answer questions on any aspect of dentistry and matters relating to the smile, gums, jaws and lower face. Member American Dental Association, Florida Dental Association, Broward County Dental Association, and Atlantic Coast District Dental Association. I have served as District Council Member of Alpha Omega, as well as serving for one term as its President. I am also a member of The Vedder Honors Society, Broward Dental Research Clinic, and Mount Sinai Hospital Guild. I have served as a Volunteer for Project Dental Health and The Tri-County Dental Health Council.


Having attained over 30 years of clinical experience in private practice in Michigan, in 2001 I was re-certified by taking and passing the Florida State Dental Board Examination. After moving to Florida, I spent nearly 10 years re-honing my skills while working as an Associate Dentist for several large dental groups. In September, 2004, I was appointed Adjunct Clinical Professor at Nova University's College of Dental Medicine. I am certified in placement of Mini Dental Implants, and I am Director of The Florida Implant Center ( On March 1, 2010, at the age of 62, I began all over again by buying a dental practice near my home in the Fort Lauderdale area. As sole owner and Chief Dental Officer of the new Nob Hill Dental Center (, I can now carefully provide dental care to patients who care, all within a caring, joyful environment. Over my career lifetime, I have provided thousands of diagnoses, fillings, crowns, bridges, root canals, periodontal treatments, TMJ therapies, partials, dentures and extractions, and dozens of implants for my patients. The only aspect of dentistry with which I have very little experience is orthodontics.

American Dental Association, Florida Dental Association, Broward County Dental Association, Atlantic Coast District Dental Society, Vedder Honors Society, Broward Dental Research Clinic, Alpha Omega Alumni Association, and American Association of Dental Implantologists. Formerly, American Academy of General Dentistry, Michigan Dental Association, Macomb Dental Society, Detroit District Dental Society, Tri-County Dental Health Council (a charitable dental care organization)

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Bachelor of Arts and Sciences in Psychology from Wayne State University Doctor of Dental Surgery from University of Detroit College of Dentistry Adjunct Clinical Professor, Special Needs Department, Nova Southeastern University College of Dental Medicine, Fort Lauderdale, Florida

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