Tooth Replacement Options
Dental Implants
Replacing Teeth with Dental Implants
The final method of tooth replacement to be considered is the dental implant. An implant is a titanium replacement for the root of a tooth. The implant fuses with the bone. A crown is then attached to the implant. The implant crown does not depend on the adjacent teeth for support or longevity. The implant crown does not invade or damage the adjacent teeth. Another major advantage of the implant is that it stimulates the bone much like a natural root does. By replacing both the root and the crown of the missing tooth we do not see the loss of that segment of the jaw bone like we do with a tooth supported restoration.
In contrast with the success rate of the tooth supported fixed bridges over extended periods of time, implant supported teeth have a much higher survival rate and have become very predictable. Immediate success rates are 98%+ and once the implants achieve osseointegration (fusion with the bone) the failure rate is extremely low. As opposed to failure of tooth supported fixed bridges, implant failure does not compromise the adjacent teeth and increase the risk of their loss.
The two most significant advantages of implant replacement teeth over tooth supported fixed bridges are that healthy adjacent teeth do not need to be ground down and the bone in the missing tooth site is preserved. Other advantages include: decreased risk of decay and root canal treatment on abutment teeth, improved ability to clean the front and back surfaces of adjacent teeth (with single tooth replacement), decreased risk of cold or contact sensitivity of abutment teeth and decreased risk of abutment tooth loss.
These advantages are so significant to the health of the adjacent teeth and maintenance of the arch form that implant prostheses have become the treatment of choice in most situations.
Since the late 1950’s the use of dental implants has developed into a routine method for treatment of the jaw with no teeth at all. Numerous studies have been published going back to the 1970’s indicating success rates in these cases of over 98%. Although long-term documentation is still not as extensive as for the jaw with no teeth, the results for single tooth replacement are excellent. The following is just a sample of the results for single tooth replacement.
- Priest 1999: 99 patients, 116 implants 10 year survival 97.4%. Dr. Priest commented that
The use of implants to support dental prosthesis (replacement teeth) demonstrated a tooth preserving effect by avoiding the use of intact teeth as abutments.
- Engquist 1995: 58 patients, 82 implants, 97.6% survival at 5 years
- Krenmair 2002: 112 patients, 146 implants 7 years 97.3% survival
- Gomes 1997: 376 patients 696 implants 5 years 96% survival
- Lindhe 1998: Combined the data of 19 studies for a total of 2686 implants, 570 single crowns and 2116 in implant bridges, 6-7 year survival of 93.6% for implant bridges and 97.5% for single implant crowns.
If we compare the data on survival of implant supported restorations versus tooth supported restorations we can see that the success rate for implant supported restorations is significantly higher.
Retreating a Root Canal Tooth or Extracting it and Placing an Implant.
Sometimes a tooth that has a root canal becomes re-infected or never became healthy after root canal therapy. The patient and clinician must then decide whether to retreat the root canal, or replace the tooth with an implant. Success rates for root canal therapy are as low as 53% and as high as 95% according to Eriksen 1991. A root canal infected with bacteria will develop a hollow space in the bone at the tip of the root. If this occurs, the success rate for the root canal retreatment is reduced 10-20% according to Sjorgren 1997.