17: Zygomatic Implant Surgery and Prosthodontics

CHAPTER 17 Zygomatic Implant Surgery and Prosthodontics

ARMAMENTARIUM

Brånemark System Zygoma TiUnite Implants Regular Platform (RP)

Implants: 30, 35, 40, 45, 50, 52.5 mm (All Brånemark System Zygoma TiUnite implants are delivered with the implant mount premounted. Each package also includes a cover screw.)

Zygoma implants: RP machined

Implants: 30, 35, 40, 45, 50, 52.5 mm

Zygoma healing abutments (40-degree angle, 3-mm diameter; 40-degree angle, 5-mm diameter)

Multiunit abutments RP

Multiunit: 3, 15 mm

17-degree angle, multiunit: 2 and 3 mm

Twist drill: 2.9 mm

Twist drill: 2.9 mm short

Pilot drill: 3.5 mm

Pilot drill: 3.5 mm short

Twist drill: 3.5 mm

Twist drill: 3.5 mm short

Zygoma instruments

Surgical drill guide: NobelGuide (If the NobelGuide is used, the guided surgery kit for the Zygoma implants must be used.)

Forceps: Gerald (toothed)

Hemostats: long, curved (i.e., tonsillar)

Hemostats: mosquito

Impression material and adhesive: Impregum PVS

Needles: hypodermic 20 gauge, 1½-inch

Pliers: crimping

Retractors: beaver tails (Henahan), Army-Navy

Scalpel: long handle

Suture: 2-0 black silk

Suture: 4-0 dyed Vicryl

Tissue conditioner: Coe-Comfort, Viscogel

OSSEOCONDUCTIVE IMPLANT SURFACES

The TiUnite surface on Nobel Biocare implants has been shown to support the healing process and to maintain initial implant stability better than machined titanium implants. TiUnite is a highly osseoconductive surface.

Indications

The indications for Zygoma implants are as follows:

• When sufficient anterior bone remains for installation of standard implants and the posterior alveolar crest has resorbed to the extent that additional implants would require the support of onlay or inlay grafts.

• In areas where an anterior onlay graft is required for implant placement and the need to extend the graft posteriorly can be eliminated by placement of the Zygoma implant.

• For partially edentulous maxillae with unilateral or bilateral loss of premolars and molars, combined with severe bone resorption. In such cases, a Zygoma implant, in combination with at least two regular implants, offers adequate support for a fixed restoration.

Preoperative Prosthetic Considerations

Many factors contribute to the long-term success of zygomatic implant surgery. As many of these factors as possible must be carefully evaluated before the surgical procedure is started. An effective team approach must be established for proper treatment planning and long-term success. The preoperative prosthetic examination and evaluation should include the following:

• Facial profile and contours

• Parafunctional habits

• Horizontal and vertical jaw relationships

• Occlusal plane orientation

• Occlusal relationships

• Status of the opposing dentition

Position and Angulation of the Implants

The tooth positions for the planned restoration should be decided preoperatively. The ideal length and angulation of implants are best achieved by using the NobelGuide (see Chapter 4). This allows selection of the most appropriate position and angulation for each implant. The existing removable prosthesis often serves as a guide for these positions. In some cases, a diagnostic wax-up is necessary. The prosthetic team must ensure that the surgical team clearly understands the tooth positions required for the final prosthesis. A good means of doing this is to provide a surgical guide. A surgical guide can be fabricated quickly and simply by making a clear acrylic resin replica of the existing removable denture or the waxed-up try-in (see Chapter 4). Except for a supporting posterior connection, the palatal area of the replica is cut away, leaving only the buccal contours of the teeth.

BRÅNEMARK SYSTEM ZYGOMA IMPLANTS

The process for implanting the Brånemark Zygoma implant follows these steps.

1. The alveolar crest, including the palatal side, is exposed, and a 10 × 5-mm window is created on the lateral wall of the sinus, close to the infrazygomatic crest. Ideally, the sinus mucosa is kept intact during this process.

2. The sinus mucosa is carefully lifted away from the area where the implant will pass through the sinus, from the floor of the sinus to the roof, with care taken not to penetrate the mucosa (Fig. 17-1). Ideally, the implant is placed as posteriorly as possible, with the implant head as close to the alveolar crest as possible.

The implant must simultaneously pass through the sinus close to the crest of the zygomatic bone and perforate the cortical bone of the zygomatic bone close to the incisura previously described. Anatomic variations may require adjustment of this ideal placement.

3. The exact point on the alveolar crest to start the drilling sequence is determined, as is the direction of the long axis of the implant based on the known anatomy of the sinus, the zygomatic bone, and its processes.

4. A retractor is placed at the previously described incisura to facilitate the correct three-dimensional orientation of the implant bone site, with special emphasis on preventing penetration of the orbital floor. The drills used to prepare the bone site for the Zygoma implant are quite long, therefore it is important to protect all oral soft tissues along the drill shaft during drilling. The drill guard must always be used, to prevent contact between the rotating drill shaft and soft tissue.

FIGURE 17-1. Caldwell-Luc approach to visualize the sinus cavity and elevate the membr/>

Only gold members can continue reading. Log In or Register to continue

Related

Stay updated, free dental videos. Join our Telegram channel

Tags: Atlas of Oral Implantology 3e

Jan 5, 2015 | Posted by mrzezo in Implantology | Comments Off

VIDEdental - Online dental courses

Get VIDEdental app for watching clinical videos

Get VIDEdental app for watching clinical videos