Are Implants the Future of Dentistry or Just a Step Along the Way?

The real future in medicine and dentistry is in regenerative therapy. While restorative materials including cements, resins, rubbers, metals, titanium etc. are the best materials we currrently have to replace damaged, diseased or missing teeth, the big picture is to replace damaged tissue with regenerated tissues. The dental pulp stem cell has been identified as a source undifferentiated mesenchymal stem cells which may have ability to differentiated into cardio-myocytes, neurocytes, myocytes, osteocytes, chondrocytes and adipocytes. So while our current restorative materials/techniques are the best available in the world, the future of dental care is tissue based rather than titanium based.

While regenerative treatments in dentistry are still years, perhaps decades away, endodontists are beginning to explore this area with what is called pulpal revascularization. This concept of taking a necrotic pulp in an immature root and stimulating revascularization of the pulp canal to allow for continued root development. Yes, I said continued root development. That is a completely new concept.

Here's another case report.


This 9 year old was at home and jumping on the bean bag and someone pulled it away, caught his tooth and completely avulsed tooth #8. It was out of the mouth for 20 minutes and properly replanted by the pediatric dentist.

A couple weeks later, symptoms presented. The tooth was opened, debrided and pasted with Ca(OH)2 paste.

Shortly after (<2 weeks) the tooth was reopened, instrumented lightly to apex, irrigated with 5.25% NaOCl, rinsed with saline and dried with paper point. A file was then used to pierce the periapical tissues to induce bleeding into the canal. An MTA coronal barrier was placed with wet cotton and IRM temporary. PLEASE NOTE THE PA LESION

At 3 month recall the tooth is asymptomatic and pa lesion has resolved.

At 9 month recall the tooth is asymptomatic and fully functional. No percussion pain, normal probings and NORMAL RESPONSE TO EPT. While there is no reaction to thermal testing, there is definitely a normal response to ept.

Looking closely at the radiograph you can see that the dentin walls in the apical portion of the root have thickened and there appears to be dentinal bridging forming in the mid-root area.

While this procedure has also been called pulpal regeneration, some argue that it should be called pulpal revascularization. It is not completely known what type of tissue that is growing into the canal or the source of that tissue (cells from within the canal or migrating in from the periapex). The continued development of the root and healing of the lesion however, is not debatable.

This type of novel treatment may give us a glimpse of the future of dental treatment using tissue regenerative techniques rather than artificial tooth replacement with traditional restorative materials.

For more information regarding the considerations of this procedure, click here.

To see more cases of pulpal revascularization, click here.

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.

Apexification after Avulsion

This 11 year old kid took a fall at the swimming pool and knocked out #8. It was out of his mouth for over an hour. It was re-implanted by his general dentist and splinted for some time.

When he came to my office the tooth was still sensitive to pressure, percussion & no response to pulpal testing. I diagnosed it with a necrotic pulp, acute apical periodontitis with immature apex. My recommended treatment was traditional apexification using Ca(OH)2. Apexification is done when the tooth is no longer vital and we are trying to create a calcific barrier at the root end, allowing us to obturate the canal.

Ca(OH)2 placed and repeated again 4 months later.

After one year of treatment with Ca(OH)2 paste, (you can see the paste resorbs over time) I was concerned that the calcific barrier at the root end had not formed. I planned to go in an obturate the whole canal with MTA, but found that a calcific barrier had formed and I was able to obturate the tooth in normal fashion.

This is the final film. As you can see, once the tooth has been obturated, the apex of the tooth looks completely normal. The next issue that this young guy will have to deal with is the possibility of ankylosis. When the tooth was originally reimplanted, it was fixated for too long of a time. For instructions on treating an avulsed tooth, click here.

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