August 1, 2007
by Blake Nicolucci, BSc, DDS
When a patient is interested in having implant therapy to replace any teeth in the esthetic zone (especially in the premaxilla), I get a sudden shiver down my spine. Completing the treatment is never the problem, but attaining an esthetic result is always a challenge. There are many items that must be considered on the pre-implant checklist before you even begin. Is there enough bone? What type of bone do we have (D1, D2, D3, or D4)? What is the condition of the soft tissue? Is it possible to develop symmetry between the implant crown and its contra-lateral crown? Is there a high, medium, or low smile line? How thick is the mucosa? Is it attached, carrotinized, or free and moving tissue? What are the oral hygiene practices of the patient?
After analyzing all of the physiological aspects of the treatment plan, then we must consider the biomechanical aspects and question marks. Will the implant be placed in an A, B-w, B-h, C-w, C-h, C-a, or D ridge? Will we use an internal hex, an external hex, a single stage implant, or an immediate load implant? Is this the place for a platform shift? Although there has been a huge advancement in all areas of implant dentistry, we can’t lose track of the fact that the basic premise in placing an implant is that we want a solid foundation on which a functional crown can be placed. Unfortunately in the esthetic zone, function is not the only variable that counts. As a matter of fact, the patient assumes that their implant will not just work, but it will be there for life. This is another item that should be addressed before the treatment is started.
If the patient has a high smile line, and you are dealing with a C-h ridge, pink porcelain can be used to ‘reconstruct’ the lost hard and soft tissues of the mouth using an FP3 prosthesis. This will look quite nice and is relatively esthetic. Of course reconstructing the hard and soft tissues in advance of implant placement is a more desirable approach. There is no one method of treating all patients in the esthetic zone, since each one differs with what he or she presents. If there is generalized horizontal bone loss on the adjacent teeth, longer looking crowns with a crown/root ratio of 1 (or greater) can be addressed with an FP2 prosthesis (one in which the tooth looks more elongated clinically — emulating root exposure or a periodontal condition).
If there is sufficient bone available for implant placement (either without or after bone grafting), then an FP1 prosthesis or crown can be used (where the crown/root ratio is greater than 1).
The following case presentation will go through the entire process of working up a patient to place an implant in the premaxilla.The following case may not ‘wow’ you with a spectacular result, but it is certainly an acceptable result. This case will illustrate a more complicated in-depth work up — to establish an adequate implant site, as well as an esthetically acceptable result.
Dr. Nicolucci is president of the Canadian Society of Oral Implantology and is Oral Health’s editorial board member for Implantology.
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