FIGURE 1--This is a 52 years old lady wearing a partial denture for her 4 anterior maxillary teeth. Her goal was only to have 'her...
FIGURE 2--The width of the ridge contraindicates implant placement. It would result in more palatal positioning; decreased diamete...
FIGURE 3--The chin is often the ideal intra-oral donor site for augmentation of this single walled bony defect. The symphysis has ...
FIGURE 4--A block is cut from the symphysis at least 5 mm below the apex of the mandibular teeth.
FIGURE 5--The graft can be detached from the lingual cortical plate.
FIGURE 6--This iatrogenic 5 walled bony defect can be easily filled with an osteoconductive material. A mixture of 50/50 demineril...
FIGURE 7--A collagen membrane (Collatape) keeps the mixture in place and helps maintain homeostasis.
FIGURE 8--The first incision line (made 5 mm below the mucosa-epithelial junction) is sutured with 2 deep and one horizontal mattr...
FIGURE 9--Measurements can be made over the soft tissues of the premaxilla so that the surgery on the Mentum can be completed befo...
FIGURE 10--This cortical and trabecular graft is an ideal osteoconductive source.
FIGURE 12--The bloc is adapted to the recipient site after the recipient site has been adapted to hold the block. This creates a g...
FIGURE 13--Four fixation screws were used to completely immobilize the block.
FIGURE 14--In order to produce a peri-implant sulcus of less than 3 mm, the distance from the future free gingival tissue border a...
FIGURE 15--All the autogenous bone particulate collected (with a sterile suction filter during the procedure in the chin) is place...
FIGURE 16--A thin layer of the residual 50/50 mixture from the symphysis is placed over the graft to increase bone density.
FIGURE 17--A barrier (Bioguide membrane) is placed over the bone particulate to stop the fibrous cells from invading the site fast...
FIGURE 18--Finally, a collagen membrane (Collatape) is placed before closure.
FIGURE 19--A horizontal mattress holds the first and the second incision at the mid line. A continuous non-locked suture on the cr...
FIGURE 20--Four months later, the block is healed & fixated with very little resorption. (The bone particulate can resorb an avera...
FIGURE 21--Optimal placement can be achieved giving due consideration to occlusion, aesthetics and a relative long term prognosis.
FIGURE 22--About 75% of each implant is placed in the graft. Bleeding in the osteotomy site is a good sign of the bone revitalizat...
FIGURE 23--The 4 implant bodies are below the tissues a minimum of 3 mm to give good support for the soft tissue.
FIGURE 24--Again 2.5 to 3 mm from the head of the implants to the future free gingival border makes a nice emergence profile possi...
FIGURE 25--The block graft will allow the implants to be placed more appropriately. This will allow them to handle the forces of m...
FIGURE 26--The bone particulate collected in the suction filter during the osteotomy procedure can be used to fill any small bony ...
FIGURE 27--The same closure as was used at the bone augmentation procedure is completed.
FIGURE 28--This x-ray shows the proximity of the apex of the implants to the nasal fossa as well as the minimum 3 mm distance betw...
FIGURE 29--Another 4 months is allowed for osseointegration in this density-2 bone. The healing of the donor site is completed. No...
FIGURE 30--The uncovery of the implants is done with the 'Split Finger Technique'.
FIGURE 31--The bone level is practically the same as it was at the time of placement.
FIGURE 32--The final abutments are prepared and torqued into position.
FIGURE 33--The provisional restoration is cemented on the abutments before suturing. It allows the soft tissues to heal with a spa...
FIGURE 34--Eight weeks later, it is time for the final impression (for cement retained individual restorations).
FIGURE 35--For ease of retrieval, the 'swedging-in technique' was used. The lab technician makes a hole on the palatal surface of ...
FIGURE 36--The crowns are cemented in place with weak cement (Temp-bond).
FIGURE 37--A round bur (# 4) is used to drill a 1 mm deep hole in the abutments through the opening in the crowns.
FIGURE 38--A composite filling is polymerilized in the holes to 'lock' the prosthesis in place. If we have to retrieve the crown(s...
FIGURE 39--This is the final result at the time of insertion. The 5 mm distance between the bone level and the first interproximal...
Implantology: How To Deal with the Most Challenging Area of the Mouth with Implants
INTRODUCTION
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'École Polytechnique de Montréal.
Oral Health welcomes this original article.
REFERENCES
1. Misch C. E., Contemporary Implant Dentistry, 1993, p. 419-444, p. 575-62.
2. Tarnow D, Magnew AW, Fletcher P., The effect of the distance from the contact point to the crest of bone on the presence or absence of the interpoximal dental papilla. J. Periodontal 1992;63 (12): 995-996
3. Poitras Y. Symphysis Graft and Implants: The Gold Standard for the Edentulous Premaxilla, Oral Health, August 2000 p 35-44.
4. Poitras Y, Benko Y., Caractéristiques de l'ancrage prothétique sur implants: visser ou sceller. Réalités cliniques, Vol. 13, No 4, 2002, pp. 367-376.
