Avoiding Root Canal Therapy with MTA

Dr. Hale's excellent post on pulp canal obliteration inspired me to share these few cases where a coronal barrier was also used to avoid root canal therapy. The most recognized reason to avoid complete pulpal debridement is biological, to maintain pulpal vitality, and thus continue root formation, subsequently improving fracture resistance, but there also exist technical limitations on the debridement procedure, imposed by anatomy or resorptive defects, that might prevent success of conventional root canal therapy.

This first example is a straightforward partial pulpotomy (or Cvek pulpotomy) with an MTA direct pulp cap. This patient had cerebral palsy and toppled out of his wheel chair causing a complicated (pulpal involvement) crown fracture of #10. You will note #9 was treated at this time as well, and if I recall correctly, was discolored and non-vital from a previous similar trauma. Multiple dental injuries (and traumatic injuries of all kinds) are very common in CP patients due to negative effects on balance. Fortunately, working with a pediatric dentist who scheduled OR time, the patient was seen within two days of the incident and the pulp vitality of #10 was maintained. Remember, inflammation in traumatic exposures very slowly spreads apically, and immature pulps with large vascular supplies are largely resistant to necrosis in the short term.

PreOp

Post-op

1-Year Recall

Please note the complete root formation.

At a 1 year recall, #10 responded normally to vitality testing. Radiographs revealed a complete formed root and a dentin barrier beneath the MTA. Astute viewers will note this success is amazingly in the absence of a coronal restoration (unfortunately, not the only time I've seen bare, unrestored MTA pulp caps succeed at 1 year recalls).

This next case is similar, although a little less conventional. As you can see in the preoperative radiograph, the root is severely dilacerated. While certainly it is possible to perform root canal therapy on this type of root (see my previous post for an arguably more challenging S curve), the difficulty level is unquestionably high. This treatment plan not only reduces the risk of instrument separation, but also saves the patient time and money, and the operator from fatigue.

PreOp

Post-Op

The key here is that this was an asymptomatic carious pulp exposure. In the case of symptoms of irreversible pulpitis, it is generally thought that an MTA pulpotomy is a more risky procedure. It is certainly contraindicated in cases with symptomatic apical periodontitis (although I have had success direct pulp capping an immature tooth with apical periodontitis).

This last case is open to the most controversy. This patient had multiple large composite restorations across the anterior maxillary dentition. He admitted to being far more motivated by financials than esthetics. His previous composite restoration and crown had sheered off unconventionally at an oblique angle to the buccal leaving a substantial cingulum. The fractured portion had been rebonded by his general dentist. This tooth had a history of trauma over 40 years ago and some extensive external resorption is visible overlapping an obliterated pulp chamber and canal. The PDL is definitely in tact and there is no history of symptoms. The option of extraction and implant placement was discussed and encouraged. The alternative treatment plan chosen by the patient is less than ideal and the patient was more than okay with a compromised long-term prognosis. I intentionally described a grim outlook to the patient, as I do with most unconventional treatments, although here I can admit that I am confident in the predictability of the patient's choice. As you can see from the preop radiographs, conventional root canal therapy is impossible due to the irregular resorptive defect sandwiched between obliterated canal space.

PreOp

PostOp

I am still waiting on the general dentist to forward over a restored recall radiograph. Hopefully I will have the image to edit in by the end of the week. You can see the post space that I prepared using a 2 round bur and a gates-glidden with the tip flattened. The post space communicated with the resorptive more coronal than I anticipated, necessitating the use of MTA as a sort of resorptive cap. I feel as long as the area remains aseptic, it is reasonable to assume a successful result.

Here is a bonus case posted on our facebook page, http://www.facebook.com/pages/Alpharetta-Endodontics/137382942943581 . I'd encourage everyone to follow there (and check the backlog of case photos) for more interesting cases.

The patient's symptoms were intermittent, spontaneous, a 6 or 7 out of 10 on the pain scale, occasionally throbbing, and worse with mastication and pressure. The key history here is the patient's remark, "it feels like my gums are coming loose from my tooth."

Make the diagnosis. I have obviously helped by circling the key components.

Intentional Replantation

Replantation of an avulsed tooth is a well known and accepted treatment following a traumatic dental injury. Preservation of vital cells in the periodontal ligament allow reattachment of the tooth in the alveolar socket. Rates of success at 5 years reported in the literature ranges between 70% - 91% (1).

The main factors limiting the success of this treatment are the amount of time the tooth is out of the mouth, disruption of the periodontal ligament and bacterial contamination.

Although not common or well known, intentional removal and replantation of a tooth is an effective mode of treatment for teeth that cannot be treated with traditional endodontic surgery. This strategy can be particularly helpful in lower second molars where proximity to the mandibular nerve and thickness of the buccal bone make endodontic surgery difficult.

Intentional replantation allows the clinician to control the variables that would limit the success of a replantation following traumatic avulsion. Atraumatic extraction, minimal time out of the mouth and aseptic technique, allow a clinician to perform apical procedures that otherwise could not be performed.

Again, while not commonplace, intentional replantation is a treatment option that can be considered in special cases. It may offer your patient a final opportunity to retain a natural tooth, when endodontic surgery is not an option.

This case was actually an UNintentional, intentional replantation. Let me explain. This patient presented to our office with a bridge from #27 to #29. Significant buccal decay was present. The general dentist and the patient wanted to try and maintain this bridge.

Her dentist placed an amalgam root surface filling under the buccal margin of the bridge. A distal periapical radiolucency developed. I was then asked to complete the RCT on the tooth. Since the anterior abutment was loose, we decided that to remove the bridge, complete the endodontic treatment, and retrofit a post and core back to the bridge. Hardly an ideal restorative solution, but a solution that worked for the patient in her particular circumstance.

While attempting to remove the bridge, the entire tooth came out. At this point, this became an intentional replantation case.

Within a matter of minutes, we did a retroprep and MTA retrofill.

The anterior abutment of the bridge was then permanently cemented on and the posterior abutment replanted into the socket.

This patient returned last week for a 3 month re-evaluation. The tooth was sensitive for a while, but she now reports no sensitivity or swelling and she can now chew nuts on that side!
If you look closely you can see that the distal lesion has healed. While this is a very short term result, the healing of the apical lesion, lack of symptoms would indicate initial success. We will continue to monitor this tooth over time. Look forward to updates!

Sources:

1. Nuzzolese E, Ciruli N, Lepore MM, et. al. Intentional Dental Reimplantation: A Case Report. J Contemp Dent Pract 2004. August;(5)3:121-130.

Catching a baseball with your teeth

This youngster tried to catch a baseball with his teeth. Tooth #9 was partially avulsed. Luckily his neighbor is a dental hygenist and knew to re-implant the tooth immediately. They called the general dentist and were at his office within 30 minutes of the accident. I got the call from the doctor to review the guidelines for treatment. As you can see, this is an immature root. Here are the guidelines for treatment of a tooth like this.

ON SITE TX:

• Immediately rinse/gently remove foreign objects. If unable to replant tooth at site of injury then use a transport media to get to dentist - milk, saline or saliva.


• If the tooth is not reimplanted, and a transport media is not used, the emergency treatment by the doctor must be done within 1 hour. (If the tooth is dry for greater than an hour, reimplantation by the dentist is generally not indicated)

AT DR'S OFFICE:

• Clean off affected area (water, saline or chlorhexidine) - don't extract tooth if it has been re-implanted.


• If the tooth is out of the mouth, prepare it for reimplantation by: cleaning with saline, soak in 1mg/20ml doxycycline, remove coagulum from socket with saline, reposition the socket wall if fractured, gently replant the tooth with finger pressure.


• Take radiograph to verify position


• Flexible splint (fishing line, mild steel wire)


• Antibiotic Rx: Doxycyline 2x/day for 7 days or Penicillin 4x/day for 7 days


• Tetnus booster

7-10 DAYS LATER:

• Remove splint


• Begin to monitor for re-vascularization (thermal testing baselines)

3-6 MONTHS:

• Continue to monitor - avoid endodontic treatment unless obvious signs of non-healing are present (pain, swelling, increasing radiolucency). It may take 3 months for the tooth to respond to thermal testing again.


• If endodontic treatment is necessary, follow guidelines for Apexification.

For more information regarding treatment of traumatic injuries: click here