Should General Practitioners Place Implants?

L. Stephen Buchanan, DDS

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INTRODUCTION
My favorite reply, when asked why an endodontist also places implants, is, “Even orthodontists place implants now, and they don’t even like to use sharp, pointy instruments!” At this stage in the dental implant revolution, there are clinicians in every specialty (except pediatric dentistry) who provide implant surgical services to their patients. It was the well-known prosthodontist, Dr. Tom McGarry, who mentored me through my first 2 implant procedures. So, the answer to the question “Should general dentists place implants?” is absolutely! With that said, let’s walk through the reasons that there has never been a better time for general practitioners (GPs) to add this procedure to their skill sets (Figures 1 to 5).

The field of implantology has solved an enormous number of challenges during the last 30-plus years since Dr. P. I. Brånemark launched this amazing technology, raising the probability of success and reducing the difficulties of placement for all of us.

Surface Engineering
While the first implant fixtures had no surface engineering to speak of (they were smoothly machined), today, every implant company knows that increasing the surface area on implant fixtures results in more effective osseointegration. While most implant manufacturers claim that their surface engineering is unique and better, the most significant difference in outcomes is between machined and roughened surface fixtures.1-3

Figure 1a. Surgical guide on 3-D printed stereolithic model. Notice facial entry sleeve for patients with limited opening (SimPlant [Dentsply Sirona Implants]). Figure 1b. Healing abutment removed after osseointegration showing healthy soft tissue and conical connection.
Figure 1c. Final restoration. Figure 1d. Radiograph showing the Ankylos implant (Dentsply Sirona Implants) with final abutment and prosthesis.

Tapered Connections
The expectation of losing bone down to the first or second thread after implant placement is becoming less common as more manufacturers have followed the tapered design of Ankylos Implants (Dentsply Sirona Implants) at the connection point between fixtures and abutments. What is now known is that this bone loss was primarily caused by flexure of butt-joint abutments during occlusal loading, causing percolation of fluids and bacteria in and out of the internal spaces of fixtures. It is no surprise that crestal bone loss used to be expected. Implants with Morse-taper connections create nearly a cold weld between parts, eliminating this continuing source of bacterial bone destruction.4-6

Platform Switching
When I began the training to do implant surgery 12 years ago, Dr. McGarry explained to me that there was a fair bit of controversy about platform switching and whether having an abutment stalk narrower than the platform of the fixture was an advantage. Currently, there are so many exceptional results with platform-switched implant systems, especially in anterior aesthetic areas, that most dentists use only implants with this feature.7,8 When combined with conical connections, anterior implants can be more predictably placed without papilla and crestal bone loss between them.

Figure 2a. Healed extraction site. Figure 2b. Pilot drill (Golden Dental Solutions) with guide cylinder to ensure centered osteotomy.
Figure 2c. Osteotomy preformed with multi-drill. Figure 2d. Post-placement radiograph of ideally postioned implant.

Subcrestal Platform Design
Implants that were designed to be placed with their platforms level with the buccal bone crest inevitably ended up in the subcrestal position in the interproximal areas, especially when implants were placed immediately after extraction of the tooth being replaced. Again, with Ankylos Implants’ roughened surface engineering over the edge of their fixture platforms, combined with a tapered implant-to-abutment connection (a design that preceded any similar implants by 20-plus years), we found that implant aesthetics and bone retention were more predictable when implants are designed to be placed subcrestally; more so in the anterior than the posterior region.9-11

GUIDED IMPLANT DRILLING
For almost 2 decades, we have had the tools to do model-based and CT-based (SimPlant [Dentsply Sirona Implants], NobelGuide [Nobel Biocare], and others) virtual treatment planning with fabricated drill guides, dramatically reducing the risk of cutting deep and wide osteotomies in our patients’ jaws. While guided drilling is eschewed by most experienced implant surgeons in cases requiring fewer than 2 or 3 implants, this tool is excellent for neophytes. Nobel Biocare’s model-based drill guide system allows dentists to carefully secure an implant analog exactly where desired in a stone model of the patient’s jaw, with a drill guide abutment that screws into the analog to hold a guide ring exactly 10.0 mm superior to the implant analog’s platform, making it a simple procedure for the clinician or a dental laboratory technician to hand fabricate a light-cured acrylic base that captures the guide ring. All told, it takes an experienced dentist 15 to 30 minutes to make one of these guides that will save much time and dramatically reduce stress when doing these new procedures. CT-guided implant placement is the gold standard—especially for complex placement challenges—and prices for treatment planning centers to make these have dropped significantly. The latest advance has been image-guided systems (X-Guide [X-Nav Technologies]) that allow dynamic drill guidance with a 3-D tracking cam­era system that reconciles a fiduciary (registration device) attached to the patient’s jaw with a fiduciary on the handpiece attachment and provide a computer-generated video image depicting the drill, the jaw, and the osteotomy in real time. All of these tools allow newbie implant surgeons to place their first and every implant in the perfect, predefined position.12-15

Figure 3a. Pre-op radiograph showing 4 mm of bone height under sinus floor. Figure 3b. Osteotome in position after upfracture of sinus floor and bone graft.
Figure 3c. Final implant placement after sinus floor was lifted another 8 mm.

BONE GRAFTING TECHNIQUES AND MATERIALS
Bone grafting, like the rest of this list, has at the same time become simpler, more predictable, and less expensive. Human bone banks now offer freeze-dried grafting material at less expensive ($85 per 7 oz) price points (BaseBone [OsteoReady Implant]), and Teflon (polytetrafluoroethylene) grafting membranes have made it possible to ideally prepare implant sites at the time of tooth extraction.

Figure 4a. Virtual treatment plan showing ideal implant position, custom abutment, and provisional prosthesis designed before the surgical placement of the fixture. Figure 4b. Immediate provisionalization of upper right and left lateral incisors.
Figure 4c. Final restorations seated on zirconia abutments.

Costs
The most fundamental implant patents have expired, so fixture costs (OsteoReady implant fixtures at $120) are coming down, setting prices at levels more in line with the general dentist’s more modest implant placement fees. Because most dental insurance companies do not cover implant procedures, it is a free market for implant fees; and credit companies (such as CareCredit) can finance these procedures for patients with no interest payments for 2 years.

Trainers
Continuing education in implant surgery has never been this good, with top-flight training available at many venues. One of the most enjoyable aspects of my entry into implant surgery has been the opportunity to be a student again, rather than always the instructor. Dr. Sascha Jovanovic (faculty at gIDE Institute in Los Angeles), my surgical mentor for the first 2 years of this trek, is a brilliant surgeon and an exceptional teacher—one of a long list of implant training gurus available to those of us walking this road to implant excellence (such as Richard Sullivan, DDS, clinical director at Nobel Biocare in Yorba Linda, Calif; Dr. Michael Pikos, DDS, bone-grafting savant whose institute is in Trinity, Fla; David Little, DDS, clinical director at OsteoReady from San Antonio, Tex; and the list goes on).

Figure 5a. Intraoral photo of preoperative condition. Figure 5b. Photo of upper and lower full monolithic zirconia restorations.
Figure 5c. Postoperative panoramic radiograph showing each prosthesis supported by 4 implant fixtures.

3-D Printed Training Replicas
Perhaps one of the most helpful tools for training dentists to place implants in their practices has come out of the 3-D printing realm. Until the introduction of TrueJaw Surgical Training Replicas (Dental Cadre) (Figure 6), dentists were left to practice on injection-molded jaw models that did not reflect the real anatomic challenges clinicians meet on a day-to-day basis. Using pig jaws, a common implant surgical training tool, is less than ideal. Pig jaw tooth morphology is very foreign to what clinicians will encounter when placing implants for their patients (notwithstanding veterinarians with pig-implant practices) and even their soft tissues handle differently than those of our patients. Cadaver heads are the real deal, but expensive and sometimes unsettling to train with, and real human patients in third-world countries offer the best surgical training experiences; however, the expenses for training in that venue are quite high for beginners. With state-of-the-art multi-ink 3-D printing, it is now possible to marry CT volumes with digital impressioning scans of real implant patients’ dental structures, to segment the teeth, perio­dontal ligaments, cortical and cancellous bone, and of course the soft tissues overlying osseous structures, so clinicians can have the most authentic training experiences short of human tissues that bleed. TrueJaw Surgical Training Replicas have soft, elastic gingival and mucosal tissue replicas that can be incised, reflected, and sutured, teeth that can all be extracted (with roots that will fracture if mishandled), bone replication that can be printed with varying degrees of density, and even sinus anatomy with Schneiderian membranes that can be used to learn crestal and lateral sinus lift procedures. Just introduced by Dental Cadre, these new teaching tools hold the potential to transform dental surgical education—including endo­dontic surgery—from an expensive and difficult process to a more accessible experience that can even be used in remote hands-on training setups.

Figure 6a. TrueJaw 3-D-printed Surgical Training Replicas (Dental Cadre) with polytetrafluoroethylene socket graft after extraction of tooth No. 30 and beginning extraction of tooth No. 28. Figure 6b. TrueJaw Replica after immediate placement of an implant fixture in the No. 28 extraction socket. These jaws have gingival and mucosal tissue replication that can be incised, reflected, and sutured; the tooth replicas have periodontal ligaments so the teeth can be extracted (with roots that will fracture if mishandled); the bone replication can be printed with varying degrees of density; and the sinus anatomy has Schneiderian membranes that can be used to learn crestal and lateral sinus lift procedures.

CLOSING COMMENTS
We are entering the age of the Super GP, a trend that has been going on for decades outside of the United States in countries with less postgraduate specialty training than available here. I have had the great opportunity to teach many young dentists who have decided to be serial students of each and every dental discipline. First, they spend time acquiring the endodontic skills that were not taught in their dental school. Then, many of them seek further continuing education for high-level aesthetic dentistry, oral surgery, periodontics, and increasingly, for implant surgical training. With dedication, they invariably become more and more competent in delivering these services for their patients, in many cases on a level matching specialty care for straightforward clinical challenges. Frankly, with drill guides, any dentist who has learned how to do a top-level root canal therapy can certainty place his or her first implant and every implant thereafter in perfect position.

Upgrading clinical skill sets is the best investment dentists can make in their career. Associates who add to their repertoire become more valuable to owners of practices, as do those in practice for themselves. Not only are patients happier when they can get implant services in the practice they know already, dentists on this path can meet their financial objectives much sooner. With that said, learning new dental procedures is perhaps the most terrifying thing we do as dentists. We are literally licensed to do dangerous things safely in human beings without causing pain to anxious patients, and our procedures must work virtually every time. So, the experience of bringing a new set of tricks to the operatory is a serious challenge for all of us.

The irony is that all experienced dentists I have trained at Dental Education Laboratories (Santa Barbara, Calif) during the last 30 years who are still passionate about their profession have continually sought training to increase their procedural capabilities throughout their careers. For those of you who are ready for the next frontier, and are willing to train up to place implants for your patients, the future is so bright you’ll need to wear shades! Those of you who are just beginning this journey will be blown away by what you will be capable of after 5 years of experience in this incredible field of dentistry.

Acknowledgment
The author thanks Dr. David Little (San Antonio, Tex) for providing the clinical cases.


References

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  2. Albrektsson T, Wennerberg A. Oral implant surfaces: Part 1—review focusing on topographic and chemical properties of different surfaces and in vivo responses to them. Int J Prosthodont. 2004;17:536-543.
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  11. Al Amri MD. Crestal bone loss around submerged and nonsubmerged dental implants: a systematic review. J Prosthet Dent. 2016;115:564-570.
  12. Parel SM, Funk JJ. The use and fabrication of a self-retaining surgical guide for controlled implant placement: a technical note. Int J Oral Maxillofac Implants. 1991;6:207-210.
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  14. van Steenberghe D, Naert I, Andersson M, et al. A custom template and definitive prosthesis allowing immediate implant loading in the maxilla: a clinical report. Int J Oral Maxillofac Implants. 2002;17:663-670.
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Dr. Buchanan maintains a private practice limited to endodontics and implant surgery in Santa Barbara, Calif, and is the founder of Dental Education Laboratories, a hands-on training center serving general dentists and endodontists upgrading their skills in new endodontic and implant technology. He is a Diplomate of the American Board of Endodontics and an assistant clinical professor at the postgraduate endodontic programs at the University of Southern California and the University of California, Los Angeles. He can be contacted via his business, Dental Education Laboratories, via the website delendo.com, or via the email address info@endobuchanan.com.

Disclosure: Dr. Buchanan reports no disclosures.

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