Internal Bleaching of VITAL Teeth

With the recent advances in regenerative endodontics, we have come to see the pulpal tissue in a new light.  This has encouraged us to treat healthy pulpal tissue in ways that would seem counter-intuitive.  For example, in the treatment of a decayed tooth, with immature roots - when the pulpal tissue is completely healthy, we may try an MTA pulpotomy on a permanent tooth, and give the tooth a chance to finish its development. We are finding new ways to perform apexogenesis procedures. The apexification procedure is becoming a thing of the past. In fact, I haven't performed an apexification in several years.

This new approach to the pulpal tissue has brought up a new questions.  In a mature tooth, with calcific metamorphosis causing discoloration, is it really necessary to perform a root canal before internal bleaching?  Conventional wisdom would say yes.  But our understanding and respect for the pulpal tissue and its capacity to repair itself has changed my view on this procedure.

First off, teeth with calcific metamorphosis are often misdiagnosed as necrotic because they do not respond to thermal pulp testing.  Electric pulp testing (EPT) is required to determine vitality on these teeth.  If these discolored teeth are determined to have vital, normal pulps and periapices - why not perform internal bleaching without RCT?

The following case is an example of this procedure.

History of trauma to #8 with gradual discoloration

Close up of the color difference

Radiograph shows pulpal obliteration - complete calcification

Normal endo access with stain removal under microscope without entering canal.  Glass ionomer barrier placed at the CEJ and Opalescence Endo placed in pulp chamber. Access closed with Cavit and bleach left for 1 week. Fresh bleach reapplied for a second week.

Access filling placed.

Before & After

With no exposure of the canal system on a vital tooth, internal bleaching can be performed WITHOUT prior endodontic therapy.

Root Canal Retreatment or Implant?

Stan, a recent reader of the blog, commented, "I'm 66 and have an abscessed pre-molar that had rct and a cap 25 years ago. Went to my dentist (who does implants) and was told rct retreatment had a 50% failure rate and the implant-cap was my best option. I had agreed and he injected anesthetic. 15 minutes later, prior to the extraction I commented on the amount of $$ that had already gone into the tooth. Shortly thereafter, after giving me Amoxicillin he said he'd do the extraction in a week. Then on my way out I learned the implant-cap would be a $2700 cost out of my pocket! I'm guessing even he felt that $4K for one tooth is a little much."

About 9 years ago I attended an implant seminar where the lecturer told the audience, "endodontic surgery is only successful about half of the time. So if endodontic surgery is being considered, you should consider extraction and implant". At the time I wondered when they would say retreatment is not successful, so you should place an implant...

3 weeks ago, the following patient presented to our office at Superstition Springs Endodontics.

This 41 year old male patient came to our office for a second opinion regarding an implant. In 5th grade he had trauma to his front tooth #9. He had root canal treatment at that time and has never had a problem until 3 months ago.

The discoloration of #9 is very obvious, however, it has never really bothered the patient.

Not a surprising root canal on a 5th grader. The apex is open, root is short, and the clincian probably did the best he could to obturate this tooth on such a young patient. Please note the normal bone and gingival tissues around the tooth. So this root canal has survived 30 years without symptoms and preserved the periodontium.

3 months ago, the tooth flared up for the first time. He had pain and swelling while on a business trip. He consulted with his general dentist regarding the issue and was presented the options:

1. Retreat RCT - which will probably not work

2. Extract & Implant - This was treatment recommended by his dentist

The patient was concerned about the cost and loss of a tooth which had given him so little problem for so many years. He sought out another general dentist for a second opinion. The next dentist sent him to our office for consultation.

Our diagnosis was: Prior RCT w/ Asymptomatic Apical Periodontitis. The tooth was currently symptom free, but had slight mobility and an obvious apical lucency.

We discussed options of:

1. Retreat RCT - confident we could improve the prior fill, we also discussed the shortness of the root and the mobility issue. We would expect apical lesion to heal, which might help with mobility, but the shortness of the root is still a factor. Nevertheless, its still the same length root he has been using for the last 30 years...

2. Extract & Implant - This is an option, but you may want to consider the short term and long term esthetic issues associated with this implant. Short-term esthetic issues would be making a single implant match the adjacent natural teeth. Long term esthetic issue would be loss of crestal bone over time.

We recommended saving the tooth.

Retreatment elected. The old, poorly condensed gutta percha was removed.

Because of the open apex, MTA was selected as the obturation material. Coronal barrier placed to allow for internal bleaching.

After course of antibiotics and bleaching treatment, the tooth is asymptomatic, less mobile and fully functional again.

I can't imagine anyone arguing that an extraction an implant is a better approach for this patient, but unfortunately there are some with that opinion. I think this may be partly due to a misinformed view of endodontic retreatment. In this particular case, you can see that the original RCT, which lasted only 30 years, without any crestal bone loss was a porous obturation. With normal probing depths and no signs of fracture, retreatment is obviously the best choice. If there are any of you with differing opinions, please share them with us.

UPDATE: 6 month recall of this tooth shows complete periapical healing. Patient reports no symptoms and full function.

In an effort to help all of us understand the treatment outcomes associated with endodontic retreatment and to properly inform our patients regarding endodontic retreatment, I hope you find this information useful.

As explained previously, the historical endodontic literature has reported the success of endodontic retreatment ranging from 100% to as low as 40%. (1) Of course with a range of data like this, you can pick out a study to support whatever argument you want to make! With a paradigm shift towards evidence based medicine and dentistry came the desire to identify the best available evidence with which to make clinical decisions. In a 2004 article by Paik et. al., it was shown that of the published endodontic literature since 1970, there were very few high level studies that had been published on endodontic retreatment. (1)

A study by Torabinejad et al. (2) in 2008 did a systematic review of research from 1970 to 2008 which reviewed outcomes date for surgical treatment as well as non-surgical retreatment in an effort to compare the two treatment modalities. Studies reviewed had to meet a certain criteria for inclusion and were rated for the quality of the study. This included details such as study type, number of patients, experience of clinician, use of magnification, materials used, age of patients etc. An interesting point was there were 3 times as many studies for endodontic surgery that met the inclusion criteria as there were for non-surgical retreatment. This review reported that the overall weighted success rate for nonsurgical retreatment was 78%. (2)

Another well-known outcome assessment study is known as the Toronto Study (3). Their evaluation of endodontic retreatment included 523 teeth on 444 patients. Of the 34% of patients who were able to be recalled at 4-6 years, 81% were considered "healed". "Healed" being defined as absence of apical periodontitis, signs or symptoms. This study points out that patients who did not have apical periodontitis PRIOR to retreatment had the highest "healed" rate at 97%, while those with apical periodontitis prior to retreatment had a "healed" rate at 78%. Another predictor found in this study was perforations. Retreatments done without a perforation had a "healed" rate at 89%, while retreatments with a perforation had a "healed" rate at 43%.

Another retrospective study looking at the success of endodontic treatment (initial RCT and retreatment) performed by a single endodontist in private practice over a 30 year period had similar results. Imura et. al. selected 2000 teeth from a 30 year career for evaluation of success.(4) The success rate for teeth treated with initial endodontic therapy was 94% and the success rate for teeth treated with endodontic retreatment was 85.9%.

In an epidemiological study of 4744 teeth that had been retreated by endodontists in US, participating in Delta Dental Insurance, 89% of teeth were functioning at 5 years. (5)

These articles are just a start. I will try to add more to this body of evidence. Please feel free to suggest any additional articles that should go along with these.

In my opinion, when considering retreatment, consider the quality of the initial treatment. Was it well cleaned and shaped? Are there missed canals? Is the obturation good length? Performed under microscope? Level of expertise of the clinician? If these things can be improved upon with retreatment, then you have a good chance for success with retreatment. I think a fair estimate would be between 80-85% success rate.

We owe it to our patients to give them the option of retreatment. It is not fair to assume a tooth has a 50% success rate with retreatment. If you are concerned about the prognosis with endodontic retreatment, consult with an endodontist. Endodontists are specialists in saving teeth.

REFERENCES

1. Paik, S, Sechrist, C, Torabinejad, M. "Levels of Evidence for the Outcome of Endodontic Retreatment". 2004, JOE 30:11, 745-750.

2. Torabinejad, M, Corr, R, Handysides, R, Shabahand, S. "Outcomes of Nonsurgical Retreatment and Endodontic Surgery: A Systematic Review". 2008, JOE 35:7, p930-937.

3. Farzaneh, M, Abitbol, S, Friedman, S. "Treatment Outcome in Endodontics: The Toronto Study. Phases I and II: Orthograde Retreatment". 2004, JOE 30:9, p627-633.

4. Imura, N, Pinheiro, E, Gomes, B, Zaia, A, Ferraz, C, Souza-Filho, F. "The Outcome of Endodontic Treatment: A Retrospective Study of 2000 Cases Performed by a Specialist". 2007, JOE 33:11, p1278-1282.

5. Salehrabi, R, Rotstein, I. "Epidemiologic Evaluation of the Outcomes of Orthograde Endodontic Retreatment". 2010, JOE 36:5, p790-792.

• 
  

Internal bleaching makes us smile!

This 13 yr old young lady had some trauma to #8 during a softball game. As you can imagine, the discoloration is of significant concern to the patient.

At the time of the exam, tooth #8 is non-responsive to thermal testing, normal to probing and mildly percussion sensitive. DX: Necrotic w/ SAP. RCT recommended with internal bleaching for esthetic purposes.

RCT completed under microscope assuring that all internal staining is removed from the pulp horns. A coronal barrier is placed in the cervical portion of the tooth. The purpose of this barrier is to prevent bleach from entering the root, passing through dentinal tubules and causing an inflammatory reaction in the pdl. Bleach (Ultradent - Opalescence Endo) is placed in the pulp chamber with a thin, button cavit temporary. Pt is rescheduled for 1 week.

Pt is excited with the new appearance of her tooth.

Final restoration is placed. Endodontists can be a valuable team member in your cosmetic cases!

Calcific Metamorphosis (Pulpal Obliteration) and Internal Bleaching

It has been reported that 11.6% - 33% of boys and 3.6% - 19% of girls suffer some kind of dental trauma before age 12. Internal staining is common following a traumatic injury to a tooth. Calcific metamorphosis is the partial or complete obliteration of the pulp following dental trauma. An interesting study of 168 traumatized, discolored, anterior teeth found that 47.6% were partially obliterated, 31.6% were totally obliterated, and 20.8% were found necrotic. Necrosis was more associated with fractured teeth, while pulpal obliteration was associated with subluxation and concussion injury. It was also noted that injuries suffered in the 1st and 2nd decades of life resulted in more pulpal obliteration, while those suffered in the 3rd decade resulted in necrosis more often.
To remove this discoloration, typically endodontic therapy is performed and internal, non-vital bleaching is performed. The following case is a variation of this procedure.

This 13 year old boy previously suffered a traumatic injury. Tooth #8 has discolored. The tooth is asymptomatic. Non-responsive to thermal testing, normal to percussion and probing.
It was decided to perform endodontic therapy, prior to internal bleaching to improve the esthetics of this tooth.

Partial pulpal obliteration is noted. A 1mm thick calcific barrier is found just below the level of the CEJ.

RCT is initiated and a complete calcific barrier is noted. It was decided to perform the internal bleaching without endodontic therapy.

A standard internal coronal barrier (glass ionomer) is placed over the calcific barrier to prevent internal bleach from exiting through cervical dentinal tubules and causing an inflammatory reaction in the pdl. A walking bleach technique is used. (Opalesence Endo)


After 1 week, pt returns and the internal bleach is removed. This tooth will be recalled to monitor vitality over time.

If pulpal obliteration occurs without necrosis, there may not be a need for endodontic therapy prior to internal bleaching. If a coronal barrier can be placed, without exposure (and possible contamination) of the pulpal tissue, then it would seem that internal bleaching could be performed without the need for complete endodontic therapy. Long term recall to monitor vitality will be done with this type of approach.

SOURCE:
Adeleke O Oginni and Comfort A Adekoya-Sofowora "Pulpal sequelae after trauma to anterior teeth among adult Nigerian dental patients", BMC Oral Health 2007, 7:11doi:10.1186/1472-6831-7-11.

Getting the Stain Out!

Following trauma, tooth discoloration is very common. The discoloration comes from the bleeding inside the pulpal chamber. The dentin becomes stained as the blood gets into the dentinal tubules and trapped in the pulp horns. The first step in restoring the natural color to the tooth is good endodontic therapy with adequate removal of the stained facial dentin and complete removal of the pulp horns. If the natural tooth color is not restored with this procedure, then the additional treatment of non-vital internal bleaching is indicated.

A common error is incomplete removal of the pulpal horns due to a small apically placed access. Care must be taken to remove stained dentin and pulpal horns while trying to preserve maximum tooth structure.

The following case shows how to "get the stain out".

Tooth #9 & #10 sustained traumatic injury.

Note the discoloration on #9.

After opening the access, staining can be seen in #9. #10 looks normal.


A round bur is used to remove the stain from the facial surface of the pulp chamber. Careful examination with magnification reveals remaining stain in pulp horns. The access is carefully refined to remove stain from pulp horns while keeping access as conservative as possible.


Following removal of rubber dam, the change in coloration is noted. Patient is informed that the tooth is dehydrated and will continue to change color until rehydration is complete. At that time, evaluation can be made if additional internal bleaching procedures will be needed.

Obturation completed.

Adequate endodontic therapy alone will often resolve the patient's esthetic concerns. Non-vital bleaching is a good adjunct for teeth requiring additional whitening.