18 Theories and techniques of oral implantology Blade implants

The blade implant, or blade-vent, is totally unlike the previous endosseous implants in both design and technique of insertion. It is wedge-shaped, rather than round like the post or pin type implants. It has a very broad face, which is aligned with the long direction of the alveolar crest. It is extremely narrow in profile, and the profile itself tapers from the shoulders of the implant toward the base to form the characteristic wedge. The body of the implant comes in various shapes suitable for different sites and contains holes through which bone can grow. Unlike the post or pin type implants, whose sites are created before insertion with drills and taps, the blade is inserted in a cut groove, then tapped deeper into position.

The blade implant has several advantages. Be-cause it is wedge-shaped and can be tapped into place, it exactly fits its site. Its broad face prevents it from being rotated on its axis by undue lateral stresses. The implant may be very long, and its wide shoulders bear two, rather than the standard one, abutment posts. Thus a single implant may support a long-span prosthesis. If an implant is needed in an area of the jaw that curves, the implant may be bent to follow the curve without weakening it. The blade may be tall or short to fit the alveolar bone height or specially cut to fit an atypical site.

In this sample presentation, the blade will be used as an abutment for a mandibular unilateral restoration.

Materials and equipment required. To insert a blade implant, a No. 700L tapered fissure bur set in a contra-angle (preferably air-driven) with a water spray attachment, a special inserting instrument to hold the blade, a plastic-headed mallet, a scalpel, hemostats, a periosteal elevator, suturing materials, and a local anesthetic are needed.

Procedures. The number of operative visits necessary for the blade implant depends on whether or not a temporary splint or prefabricated prosthesis is to be worn over the implant until final cementation. However, the protection from the temporary splint is not essential when using the blade-vent unless the implant has been set in extremely thin bone that might fracture under even moderate stress. Also, a temporary splint might be desirable for esthetic reasons, particularly when an anterior restoration is involved. Otherwise the blade may be left unsplinted. Not only will exposure of the site speed healing, but the danger of the splint's impinging

on the unhealed, swollen soft tissues is obviated. The ability to leave the blade unsplinted is unique, for other endosseous implants must be splinted be-cause they loosen as bone dies back after their insertion. The blade, however, because of its method of insertion, shape, and large surface contact with bone, rarely loosens enough to impair bone regeneration. Thus, unless some form of temporary splint is desired for some other reason, three to five visits are all that are necessary for a blade implant restoration.

First visit. In this case, the first visit involves radiographic studies and preparing a single natural tooth for a full crown restoration. Impressions are made for a veneer crown casting.

Second visit. The casting is fitted over the anterior abutment tooth and properly trimmed for occlusion and gingival fit, then the implant itself is inserted. With a scalpel, a long incision is made along the fibromucosal tissue on the crest of the ridge. This incision should be slightly longer than the anteroposterior length of the blade (Fig. 1-48). It should go right through the periosteum to the bone. No cross incisions are necessary, as they delay healing.

The tissue is reflected buccally and lingually with a periosteal elevator. A No. 700L tapered fissure bur in a contra-angle with a water spray attachment is used to make a groove in the bone along the crest of the ridge. This groove should be the same depth as that of the blade portion of the implant and its mesiodistal length should correspond to that of the blade (Fig. 1-49).

The implant is placed into the groove with an inserting instrument (Fig. 1-50). A plastic-headed

Fig. 1-48. A sharp, clean incision is made with a scalpel along the fibromucosal tissue covering the crest of the ridge.