Robotic-assisted dental implant placement technology: overview, implementation, and case report

Dr. Bruce Smoler discusses the clinical benefits of robotic-assisted implant surgery

Abstract

Background/Purpose

This article aims to highlight the evolution of robotic haptic dental implant technology — the advances, implementation, and review of a case study.

Results

Robotic-guided implant placement can effectively help save significant patient treatment time while offering high precision with predictable outcomes.

Conclusion

Robotic haptic-guided implant surgery provides unique clinical benefits for patient care presently unavailable with any other type of technology.

Introduction

Dental implant therapy has always been considered a prosthetically driven modality with the final tooth position supported by implant services. In 2022, the majority of FDA-cleared dental implants have relatively good survival and clinical success rates.¹ Interestingly enough, the marketplace has placed a focus on precise implant placement in 3D, unlike 20 years ago when the focus was on osseointegration itself. The proper positioning of implants seems to be of paramount importance to the long-term success more so than the implant-to-bone interface. Proper implant placement seems critical to achieving the most pleasant esthetic outcome.²

Moreover, the survivability of implants vis-à-vis peri-implantitis relative to the correct positioning of the fixture has also been studied. One study estimated that nearly half of the peri-implantitis cases could be caused by implant malpositioning.³

Certainly through the years, advances in technology have helped both the visualization of the prosthetic outcome and surgical implantation. One key factor is the increased use of computer-aided planning for implant surgery. The ability to simply preplan a case on software in three dimensions combining the surgical and prosthetic components before any treatment has been started has been quite revolutionary.⁴ Improved scanning technologies and surgical procedures have evolved to offer today’s clinicians ways to increase efficiencies and ensure accurate implant placement while helping to drive restorative options. This has resulted in ways to increase case acceptance and deliver same-day procedures.

The surgical guide bonanza

For decades, implant surgeons performed freehanded placement based upon what some have termed “brain guides.” The optimal implant position, long-term survivability, and esthetics were directly related to the surgeon’s capabilities, experience, and knowledge. This required a large amount of preplanning and workup with photos, bite evaluation, clinical observation, and in some cases a wax-up of the proposed implant placement. Subsequently, the explosion of available software packages to help connect the patient’s clinical parameters with the expected surgical outcome allowed for an increase in surgical predict-ability with the advent of surgical guide options.

Surgical guides can be classified as the following: static guides (tooth-borne, soft tissue-borne, stackable; i.e., NDX^®, Chrome™), dynamic guides (X-Nav Technologies, Navident), and most recently, robotic-assisted implant placement (Yomi^® by Neocis) (Figure 1). To be sure, not all guides are created equally. One study found a significant variation between the accuracy of a tooth-supported guide and tissue-supported guide.⁵ Increasing the ease-of-use of various computer software diagnostic systems has increased the ease-of-use and availability of surgical guides. As recently as a few years ago, obtaining a static surgical guide often required days if not weeks, due to the lead time necessary for impressions, scans, guide design, and fabrication.

With 3D printing and more intuitive software, static surgical guide fabrication has reduced the workflow consistently to days not weeks. Aside from the ease of fabrication of surgical guides, the mainstream acceptance of this workflow has only added to the widespread use of surgical guides in implant surgery. However, one often overlooked subject is “Who is guiding the guide?” Some practitioners have felt a higher level of confidence, a phenomenon known as “risk homeostasis,” not due to their increased skill set, but simply relying upon a guide to allow them the predictability they seek. Extensive evidence has shown the fallibility of static guides requiring the use of freehanded surgical procedures if and when a guide goes wrong.⁶ Ill-fitting and poorly designed guides can occur with static guides. Additionally, static guides are made for just one preplan and cannot be altered if the clinical conditions change, rendering the guide useless. Physical guides can decrease visualization and limit the cooling of the drilling sequence through the guide. Overheating has been shown as a risk of static guides, which block access to the surgical site.⁷ The inability to reliably place or seat the guide due to variations in clinical conditions and a myriad of unexpected surgical complications are all reasons a surgeon should not substitute knowledge and experience in lieu of the use of a guide. It’s been said that guided surgery can make the experienced surgeon better, but it cannot make a beginner surgeon accomplished. A clear understanding of the limitations, goals, and objectives of using static guides is required to accurately assess the risks, benefits, alternatives, and complications. Once done, the distinct advantages of an alternative protocol of robotic-assisted implant placement will become evident (Figure 2).

Robotic-aided procedures in healthcare and the dawning of haptically guided technology

Robotic-assisted procedures started in the late 1990s in the medical field. Today it has become the standard of care in a multitude of minimally invasive surgical procedures in medicine globally.⁸ One key to understanding the differences between the first and only FDA-cleared, robotic-assisted dental implant device and other robotic devices in medicine is knowing about the technology. In dental applications, the Yomi^® allows the surgeon to guide the drill based upon the intended surgical preplan. It is not remote-controlled (called telerobotics), but directly under the control of the surgeon. This direct involvement allows the surgeon to be in control to confirm that the execution of the implantation is indeed following the desired placement. The robotic guidance is designed to prevent any iatrogenic-induced errors or variations of the intended plan. Dynamic guidance without haptic robotics still requires the surgeon to follow the plan. With dynamic guidance, the surgeon is not restricted physically from inducing errors such as off-angle drilling, chatter of drills in the osteotomy, as well as overpreparing the implant site in depth or angulation. The surgeon must focus on a screen and cannot directly observe the drill site while utilizing the benefits of dynamic placement. Robotic-assisted placement allows for visual, audio, and haptic guidance during the osteotomy preparation and the implant placement. These are the main differences between dynamic guidance and robotic-assisted implant placement.

Robotic-assisted implant surgery allows the surgeon to guide the handpiece directly to match the preplanned surgical implant position. The specific technology that sets robotic-assisted guided surgery apart from dynamic guidance is the use of haptically guided stereotactic guidance. There is no other technology available on the market today that allows the control and precision to follow a preplanned surgical plan as intuitively. The ability not only to have visual and audio cues, but also most importantly to provide tactile feedback is unique. One of the only drawbacks of Yomi is that it is contraindicated for use with patients who have insufficient bone or teeth to retain a splint rigidly throughout a surgical procedure.

Implementation of new technologies

One of the most challenging roles of a business owner who happens to be a dentist is incorporating new technologies in the dental office. All too often the dentist embarks on a journey without holistically including the rest of the organization. The result is that often new technology becomes less likely to be used on a consistent basis. Moreover, if the technology happens to have a higher learning curve, cost or staff involvement, and training, the return on the investment is even less likely to occur. Taking a page from other industries to implement new technologies can be quite useful when incorporating robotic-assisted implant procedures. Without a game plan to have the whole office staff involved and excited, the owner operator is left to feel like Sisyphus pushing a boulder uphill day after day.

One technique is to tie the benefits of the new technology to the core values of the office. Once the team can see the value of the new technology and how it benefits patients, there should be fewer hurdles to overcome. Given the ability to get the team onboard with an open mind, the next step is to have clear-cut ways to build systems to help utilize and optimize the new technology. In business the use of the Eisenhower Matrix is an effective way to eliminate, delegate, plan, and do (Figure 3). Typically, this is achieved once the training allows for systems to become grooved in, and the “flow” of the procedures can become very smooth. Finally, once having the systems in place and the team onboard, the office will be able to realize maximize efficiency and performance.

Our team utilizes the concept of “name it, want it, get it” when formulating plans to bring new technologies into the practice. The clear focus of being able to name what it is we want to achieve, the reasons we want to achieve it, and a way to get it are all central to the successful use of new technology. Two apropos quotes from author Napoleon Hill follow:

“Success is good at any age, but the sooner you find it, the longer you will enjoy it.”

“A goal is a dream with a deadline.”

Case review

A 51-year-old female patient presented at the end of business day with hopeless tooth No. 30 (Figure 4). The patient had a previous history of endodontic therapy with a 10-year-old full crown placement. Recently, she had lost the crown restoration, and the area around the tooth was irritated. She wanted a replacement. Initial images of the tooth, CBCT scan, as well as intraoral examination, revealed hopeless tooth No. 30 with presentation of immediate implant replacement with minor bone grafting and PRGF bone graft modifications. A review of the patient’s health history, as well as informed consent and financials, was performed. The patient had a history of implant replacement 10 years ago and desired immediate placement due to her hectic work schedule.

Panoramic CBCT view shows the robotic tooth-borne splint in place on the patient’s lower left side (Figure 5). This link allows for both the registration of the preplan to the intraoperative 3D space as well as the direct connection of the patient to the robot via the tracker arm. This connection allows the real-time movements of the patient to be precisely tracked by the robot, so minor movements of the patient do not reduce the accuracy of the implant placement from the preplanned idealized placement. In other words, no patient immobilization is required, and the 3D plan moves with the patient during the procedure. The evaluation of the implant placement site was 10.5 mm in width and had a residual intraseptal width of 3.6 mm at the coronal portion. Additionally, the remaining bone above the inferior alveolar nerve was abundant with 17.7 mm of bone (Figure 6). A BioHorizons^® 4.6 x 12 mm tapered internal implant was selected in the Yomi Plan software.

Clinical notes

The patient was adamant to have work done at the same visit due to her past experience, although her upper-left implant replaced a single-rooted tooth. Obviously, an immediate placement of a two-rooted molar poses more challenges for initial stability than a single-rooted bicuspid. We discussed the use of our Yomi. The patient was agreeable to have her surgery done all at one time. The requirement to place an implant in an immediate extraction site requires a higher level of precision for a number of reasons: Osteotomy drill chatter can lead to an over expansion of the site preparation leading to poor initial implant stability. Poor access and visibility as well as implant location, which can migrate to the mesial root or the distal root, are all common occurrences. The need to have a guided approach is central to a predictive, successful outcome.

However, the desire to offer not only a same-day guide, but also a guided approach immediately for an emergency patient meant the only way to achieve this was with a robotic-assisted device. The before-and-after periapical views show a clear representation of what is possible with immediate molar replacement with the robotic-assisted implant device (Figure 7). The preplanned surgery was followed precisely with the implant being placed in a predetermined position mesial to distally as well as apically. The initial insertion torque was measured at 40Ncm. The patient had no desire to have an immediate provisional placed. The patient returned at the 2-week mark for suture removal with uneventful healing. At the 3-month mark, she will be evaluated with an Osstell^® reading for implant stability and an intraoral scan for her final prosthetic.

Robotic workflow

There are several steps in the sequence of the delivery of robotic-assisted procedures. Proper training and guidance are providing new technologies promptly, efficiently, and effectively. The start-to-finish of the presented case was less than 45 minutes from the time of the new patient arrival to case conclusion. The steps are as follows for the orchestrated movements of the team to be able to provide such a high level of care promptly, efficiently, and expeditiously:

• Complete removal of tooth as atraumatically as possible.
• Attach tooth-borne splint to opposite side of same jaw to allow for linking the patient to the robot.
• Take CBCT with fiducial array in place attached to the splint.
• Load CBCT to the planning work station to virtually plan the placement of the implant to the extraction site.
• With advanced features, a dynamic plan can allow for desired placement and planning of the implant based upon clinical conditions.
• Attach patient to the robot with the tracker arm end effector attached to the splint once the fiducial array is removed from the splint.
• A few steps to “landmark” and guide the handpiece and arm to the surgical site.
• Changes to the plan can be made by simply selecting “Place Implant at Tip” mode to confirm the clinical position and the preplanned virtual position. A critical differentiator when comparing the robotic-assisted guidance to any static-guided technology is the ability to change the virtual plan during the case.
• Once ready for the drilling sequence, the robot is placed in the “Guided” mode, and the drill/handpiece is moved with haptic feedback to mirror the virtual plan precisely.
• When the drill sequence is complete, the placement mode is selected to place the implant in the exact location with no deviation, chatter, or skiving (bouncing) of the virtually planned placement.

With a well-trained team, the process becomes smooth and seamless. The surgeon’s time is limited to just the actual placement of the implant with the setup and preplan work delegated to the robotic coordinators. The bottom line is a huge advantage over any other static guide as well as any other dynamic system due to the haptic feedback allowing for the placement of the implant precisely where planned. All in all, this service had greatly increased our ability to deliver precise implant placement in a predictable, efficient manner.

Conclusion

If surgical guides can improve the accuracy of implant dentistry, and robotic-assisted haptically guided implants offer a distinct advantage over any other guided system, a closer evaluation of this advanced technology is suggested to provide the highest level of precision in guided dental implant placement.