Coronal breakdown of the involved tooth. Evaluation of the condition of the tooth in question and of the potential for success requires clinical judgment. If the chance of success of endodontic therapy is questionable, extraction of the tooth may be a better alternative than leaving the tooth in the mouth. If at least one-half of the coronal tooth structure is remaining and the root canal anatomy does not present an atypical appearance, endodontic therapy probably is the best choice.⁸. A candid discussion of the possibility for endodontic therapy success should be held with the patient before making a decision.

Type of bone supporting the questionable tooth. Usually, the best chance for implant success is in the mandible or the premolar and anterior portions of the maxilla. The posterior maxilla usually has poor bone density and, therefore, a reduced chance of implant success. A tooth in the posterior maxilla with a reasonable chance of endodontic success should be retained, since successful placement and long-term service of implants are less likely in the posterior maxilla than in other parts of the mouth. Any area with questionable or abnormal bone density or the presence of potentially problematic anatomical structures should persuade practitioners to retain teeth and choose the endodontic alternative.

Is the tooth to support a single crown or a fixed prosthesis? If the tooth in question is planned to retain a single-tooth restoration, strength requirements are lower than those for a tooth planned to support a fixed prosthesis. For optimum longevity expectations, highly questionable nonvital teeth that are planned to provide support to fixed prostheses probably should be replaced with implants.

Occlusion. Practitioners know well that a significant percentage of the population experiences bruxism or clenching.⁹ Teeth in these patients are required to resist enormous chewing forces. In such situations, teeth that have a questionable prognosis for success of endodontic and restorative therapy probably should be removed. However, in bruxers and clenchers, tooth replacement with implants and crowns also has questionable clinical success potential, because of the extreme forces placed on the teeth in such patients.

If it is elected to remove a tooth and place an implant in a bruxer or clencher, the dentist should consider occlusal equilibration, followed by placement of a postoperative occlusal splint for nighttime wear to reduce the expected occlusal trauma to the implant and restoration.

Periodontal condition. One of my pet peeves is being asked to treat patients who have received implants and who also have periodontally treated teeth with mobility classifications of 1+ to 2 (on the 0-to-3 scale). In such cases, the teeth move significantly under occlusal stress, while the implants move only slightly during chewing. Long-term acceptability of the restorative/prosthodontic therapy is extremely questionable.

The negative restorative considerations related to the differences between the stability of implants and mobile periodontally treated teeth should indicate retention of questionable nonvital teeth, if at all possible. Teeth in such patients often do not have to support extreme forces. Teeth that may not be strong enough to survive in the mouths of clenchers or bruxers may have adequate strength to serve in periodontally treated patients.

Patients’ perception of treatment. Many patients fear both endodontic therapy and even the mere thought of surgery. The dentist should describe candidly the potential discomfort to be expected with each type of therapy to ensure that the patient understands what to expect during treatment.

Patients’ perception of the psychological and physiological trauma related to each therapy may be one of the key factors in their decision.

Overall health. Many factors—such as smoking, poor systemic health and major systemic diseases—may contraindicate the placement of implants. Similarly, some of these factors may influence the potential success of endodontic therapy. Patients should be advised of these negative factors in relation to their planned therapy.

Overall health must be considered in any decision between implants or endodontic therapy. It has been my observation that on the basis of overall health characteristics, endodontic therapy may be indicated over implant surgery in some cases.

Time needed for treatment. Although some implant placement situations allow immediate loading with the restoration, many implant situations require several months for adequate osseointegration to occur before the restoration can be placed.

Patients’ perception of the psychological and physiological trauma related to each therapy may be one of the key factors in their decision.

If the dentist anticipates a major difference between the two types of therapies in terms of the time required to complete them, patients should be encouraged to express their opinions related to selection of one or the other treatment on that basis.

The practitioner’s proficiency. Practitioners have differing degrees of expertise in the various areas of dentistry. Unfortunately, many patients do not want to be referred to other practitioners for a portion of their treatment. In such cases, general dentists should advise the patient about the expected potential for success for each of the therapies if they were to accomplish the treatment themselves without referral to specialists.

If the patient feels that because of the clinical expertise of the practitioner, one or the other therapy has the greatest chance for success, that therapy is the one to choose in that situation.

Potential esthetic result. Sometimes implant/restorative therapy can be accomplished with the expectation of adequate or even excellent esthetic acceptability, while other clinical situations appear to be difficult with regard to esthetic acceptability using implants and implant-supported crowns. When the potential for esthetic acceptability appears to be questionable if implants and restorative therapy are used, retention of the affected tooth may be a better choice.

Overall postoperative expectations. When all of the preceding characteristics are considered and weighed together, experienced practitioners can estimate the overall potential for success of either implant/restorative or endodontic/restorative therapy, and they can arrive at an educated prognosis. Consideration of any one factor alone may lead to an illogical conclusion about the best therapy.

All of the factors discussed above must be considered to make a valid conclusion about whether to extract a tooth, place an implant and restore it, or accomplish endodontic therapy and the required restorative therapy.

	SUMMARY

TOP CHOOSING BETWEEN IMPLANT AND... SUMMARY REFERENCES

 
The decision to accomplish endodontic therapy and restore a tooth or to extract it was a relatively easy decision in the past. However, in 2006, a complicating factor is present: the observable success of dental implant therapy. Many factors discussed in this article relate to whether a tooth should be retained, treated endodontically and restored, or replaced with an implant and an implant-supported restoration.