Guided Implant Surgery and the Blind Skier

Trust and Vision on the Mountain

First chair! I am reaching the top of the chairlift ride on a sunny, crisp morning in the Colorado Mountains. It snowed 8 fluffy inches the night before. Its called a “bluebird day” in skiing terms. I cant wait to begin my decent from the top of the world down through the chutes, trees and bumps with  “freshies” hitting my face and the feel of your body “floating “through the new powder. It doesn't get much better than that!

As I reach the top and get myself together to start my run to the bottom, I look over to my side and I see a blind skier. I know this because she is wearing a vest with “Blind Skier” emblazoned upon it. Her “seeing eye friend” is next to her. Curious, I ski up next to them.

“Beautiful bluebird day, isn’t it?” I remarked.

“Yes. Perfect”, she replies.

“I am curious, what made you take up skiing as a blind person?” I asked. “Isn’t it scary to hurdle yourself through the unknown – down a treacherous, and steep mountain?”

“It could be,” she responded. “But because I have complete trust in my companion, I am able to concentrate on the feeling and beauty all around me.”

“But you can’t see!” I retorted inquisitively.

“Not true”, she remarked quickly. “I ‘see’ the perfection all around me. It’s beautiful, is it not?”

“Yes”, I stumbled.

“You just need to create a vision in your mind’s eye of what you want to see and picture that as the outcome!”

“Amazing”, I said.

“Remember the vision and enjoy your day,” she said as she skied away, leaving fresh tracks behind.

“I will.  Thanks. You enjoy yours.” I responded.

Beautiful!

Trust and Vision in the Clinic

I thought about my encounter with the blind skier all day. I kept thinking about the “vision” she talked about and how “trust” was the key to that vision. Although there is some significant life learning in that statement, there is also a very practical application of trust and vision when it comes to implant guided surgeries.

Guided implant surgery has become state of the art for predictable implant design and placement. Obtaining CBCT scans of the patient; creating diagnostic (digital design) wax-ups; utilizing design software (e.g., Simplant) to orient implants for precise size, angle and depth; and creating accurate surgical guides directly from the CAD designs are routine processes for many implants placed today. It’s almost become a “no- brainer!”

(Click this link for more articles on dental implants.)

Therein lies the problem! We can become so dependent (trustful) on the power of the new technologies that we may easily lose the “vision” of where we want to go and what the final outcome will be. We don't always use our brains (think). This may be bit of an editorial comment or viewpoint, but it is important to “stay the course” of predictability and outcome. New technology is fantastic, but we must apply knowledge, experience and skill to achieve expected results.

Guided surgical indices (Figure 1) are created from scanned models correlated to the CBCT scan of the patient. The guides are milled or printed to provide accuracy within 0.01 percent tolerance levels. Generally, three guides are fabricated with different-sized drill diameters to aide the placement of the implants to exact depth and angle based upon the original CAD design for the case. The sequencing of the guides allow for efficient and predictable results. There is significant “trust” inferred to these guides. But one may notice with the guides that because of the design, the outline and shape of the tooth to be replaced are no longer visible. The “structure” of the tooth has been replaced with the respective drill guides to aide in placement. Complete trust must reside in the planning and stability of guides to achieve any predictable outcome. Errors can happen through any of the steps in the process. The goal is not only to minimize error, but also to have the ability to evaluate if an error has occurred. Utilizing a second auxiliary guide is paramount for success.

Creating an implant surgical guide that maintains tooth contour and shape is critical to verify proper depth and angle of the implant during surgical placement. It’s your “backdoor” to predictable results. This article will demonstrate how to fabricate a simple but effective guide for implant placement. It provides the “vision” necessary for acceptable results.

In this patient, tooth #10 is to be removed and an implant is to be placed (Figure 2). Tooth #10 had previous endodontic therapy more than 20 years ago. It was restored with a large post and core followed by a porcelain to metal crown.  The patient was not pleased with her tooth esthetics and the “black line” around the crown. A maxillary reconstruction was recommended and begun. Upon removal of the existing crown on tooth #10, a fracture in the root was observed. Implant placement was recommended.

Prior to the implant surgery, a diagnostic wax-up was created. The patient also had a CBCT and the CAD design for implant placement was performed. To fabricate the surgical guide a Great Lakes Mini-star matrix (1.5 mm copyplast) was fabricated from a model of the wax-up (Figure 3).

The gingival margins were marked on the working model and tooth #10 was removed from the stone cast, creating an ovate shape of the ridge. The copyplast was then contoured precisely to the apical extent of the facial aspect of tooth #10 (Figures 4 and 5).

A palatal hole was drilled through the copyplast matrix to act as a guide for implant angulation at the time of surgery (limiting the facial angulation to the facial/incisal edge). This guide became part of the surgical armamentarium for implant placement.

At the time of surgery, the anterior provisional was removed and the surgical guide placed. The pilot hole was made through the palatal access of the guide. The periodontal surgeon placed the implant to its ideal depth – 3 mm apical to the facial margin of the proposed restoration. The depth was checked and the surgical site closed (Figure 6).

As can be seen from the post-surgical CBCT, the head of the implant was correctly placed 3 mm below the facial margin of the provisional present in the radiographic image. Ultimately, the implant was integrated and the final maxillary reconstruction was completed (Figure 7).

The emphasis of this article was to point out that “trust” in the surgeon and “trust” of guided surgery are necessary and harmonious. However, it is important to use the  “vision” of where the implant is to be placed, relative to the adjacent teeth. A simple surgical guide, fabricated from a wax-up, can easily provide that critical information. Using your eyes and trusting your judgment will help you achieve amazing results.

Nothing can take the place of clinical skill, judgment and experience, but don’t be “blinded” by the new technologies!

(Click this link for more articles by Dr. Jeff Bonk.)

Jeff Bonk, DDS, PC, Spear Contributing Author - http://jeffreybonkdds.com