August 1, 2003
by Yvan Poitras, DMD
Ten to 15 years ago, the majority of our implants cases involved the completely edentulous mandible. We gained a lot of experience restoring those cases. Now the demand is directed more toward partially edentulous situations. Actually, it is not rare now that we are challenged with reconstructing ‘the aesthetic zone’, which can be quite difficult. Through our previous cases, we have now gained the knowledge to manage these new situations with relative confidence.
The time when the residual ridge dictated the number and the position of the implants is history. Today, aesthetics is important to both patients and practitioners. This has driven the development of surgical and prosthetic technologies through innovation and research — as well as competition among manufacturers. This case presentation will illustrate our technique for restoration of the partially edentulous maxilla using autogenous bone and dental implants.
Beyond the Limits of the Anatomical Structures
The replacement of failing anterior teeth in the premaxilla with implants is, aesthetically, one of the most difficult treatments to perform. In fact, following tooth extraction, a long interruption of the functional loading on the alveolar bone leads to the reduction of the trabecular and vascular density of the surrounding bone tissues, as well as its volume. For this purpose, many methods such as the use of substitutes for filling bone defect, growth factors, membranes known as guided tissue regeneration or their combinations were used. Autogenous hard and soft tissue grafts are superior to allogenic and xenogenic filling materials. They do not involve immunologic reactions and are replaced by the resorption/bone formation mechanisms of the host. The intra-oral bone grafts used in the atrophied alveolar ridge treatment are standard method for the re-establishment of bone dimension. Intra-oral donor sites for autogenous bone harvesting include: the maxillary tuberosity; the symphysis of the mandible; the external oblique ridge; the ramus and any available exostosis. The use of these intra-oral sites reduces the risk of scarring, minimises resorption of the graft, maintains the osseous density, allows intra-oral access, ensures proximity of the donor and recipient sites, reduces morbidity, allows for maximum comfort, and avoids dermal scarring.
Visualization of the Result Prior to Initiating Treatment
It is generally known that using implants to restore the normal contour, comfort, function, aesthetics, speech, and oral health of a patient requires visualization of the result prior to initiating treatment. The diagnosis must be the basis of any therapeutic approach, whereas, unfortunately, the morphology of the osseous defect is still generally regarded as the basis of the decision-making for implant placement. On this basis, the techniques for restoration of hard and soft tissues allow the creation of the conditions necessary for the maintenance of the results desired. Indeed, the regeneration of the osseous ridge will regenerate more ideal conditions by restoring the desired initial contour.
Dr. Yvan Poitras is Founder and Director of the Canadian Implant Institute (Recognized provider ADA CERP), which provides training in both surgical and prosthetic aspects of implantology. He divides his time between his private practice, limited to implantology, teaching and international lectures. He is affiliated with the research group in Biomechanics/Biomaterials at l’cole Polytechnique de Montral.
Oral Health welcomes this original article.
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