These combined CBCT and prosthetic disciplines go one step further; when technology allows clinicians to have interactive communication through online modalities...the surgeon, the radiologist, and the prosthetic doctors can collaborate as a team, producing a plan implemented through surgical guides.
This month’s Implants Today is focused on dental implant surgical guides. A surgical guide for implant placement is a comprehensive blend of many technologies that translates to improved care for our patients. It was only in 1979 that Hounsfield and Cormack received the Nobel Prize for Physiology and Medicine for developing the diagnostic technique of x-ray computed tomography (CT). Here we are, 36 years later, and we can routinely place dental implants through a guide that that is computer assisted designed (CAD) and computer assisted milled (CAM), created from information obtained by a CBCT scan. Not only is this a blend of technologies, but the true success of a surgical guide for dental implant placement is the combination of taking those technologies and making them work in concert with a plan for the prosthetic end result. Because of this melding of a prosthetic goal with technologies that support it, implant dentistry treatment planning has now entered a stage that is extremely predictable and safe on every level. These combined CBCT and prosthetic disciplines go one step further; when technology allows clinicians to have interactive communication through online modalities (ie, Skype and GoToMeeting), now the surgeon, the radiologist, and the prosthetic doctors can collaborate as a team, producing a plan that can be implemented through surgical guides. This, in my opinion, is ideal treatment planning through a team approach and treatment.
One important key to success with a surgical implant guide is to create a guide, or a series of guides, starting with accurate diagnostic records. This includes detailed impressions especially for tooth-supported guides and accurate face-bow transfers for larger and full-arch cases. One key starting point for guide cases is capturing a CBCT scan with radiopaque teeth on a prosthesis, then being able to see the tooth positions on a CBCT scan for a surgical plan based on the prosthetic position desired. Another option is to take a dual-scan technique where radiopaque markers are placed on a prosthesis, then a CBCT scan of the prosthesis is taken both inside and outside of the mouth. The 2 scans are then correlated in a CBCT software program and then a prosthetic-based surgical plan can be made. The information from either type of these 2 scan techniques, allows planning not only for implant positions but also to determine if either grafting or alveoloplasty are needed. These diagnostic records and radiopaque scans are the starting point for either an online meeting planning session or planning session within a clinician’s office using one of the many available CBCT planning software options.
Surgical guides are planned either from a tooth- or soft-tissue-supported (eg, when a patient is edentulous) clinical situation. A tooth-supported guide offers the most stable reference for a surgical guide. Accurate impressions are important so that a surgical tooth-supported guide fits accurately over the existing teeth. Impressions for this can also be taken with one of the many optical scanners available, and a working model can then be made from the scan. When teeth are stable and support a guide well, the guide can provide a very simple and accurate implant placement for one or multiple teeth. Utilizing an implant manufacturer’s or guide company’s kit, implants can be placed through a guide using guide sleeves. The option also exists to utilize a guide for the initial osteotomy preparation, and place the implants freehand, gaining an improved tactile sense. This has been labeled template-assisted surgery in the literature by Dentistry Today’s implant advisory board member Dr. Scott Ganz.
When a full dentulous or an edentulous arch is being treatment planned for dental implants, surgical guides become more complex on every level, from the planning to implant placement and alveoloplasty, if needed. In the maxilla, a patient’s aesthetics and lip-line become an integral part of the planning process that will then be related to implant positions. When creating a prosthetically based surgical plan for a full arch, occlusion, the anterior-posterior spread, aesthetics, alveoloplasty, bone augmentation, provisionalization (and more), become topics that need to be more seriously considered than when treatment planning simply a quadrant of implants.
In my opinion, the biggest challenges in full-arch reconstruction and treatment planning with a surgical guide are with the treatment of cases that involve removing an entire arch of teeth and then relying on a guide for alveoloplasty and implant placement. Once an entire arch of teeth are removed, the occlusal reference is now eliminated and all of the pre-planning with a guide becomes dependent on the accuracy of the plan and how the guide fits onto the remaining bone after tooth removal. Surgical guide systems now exist that address this challenging issue.
With the refinement of CBCT scan technology and adjunctive CAD/CAM and communication technology, implant surgical guides can offer many solutions to assist in varying clinical situations. The current surgical guide systems address every situation, from partial- to full-arch edentulism. As technology improves even more, guided surgical assistance will further the clinical successes that we see now.
From an anatomical standpoint, it is important for the clinician to clearly understand the anatomical landmarks of bone and the innervation points that are associated with them. This is especially true for more advanced grafting cases and sites. There are plenty of continuing education venues available....
Ideal bone support affects the health of dental implants in many ways. Not only is bone around a dental implant needed to support the implant, but the surrounding bone also supports the soft tissue, which in turn affects hygiene, aesthetics, and the overall health of the implant itself. Bone grafting, to support deficient bone for implant placement and health, is often a concurrent discipline of dentistry that goes hand in hand with implant treatment. This month’s Implants Today has an outstanding article by Dentistry Today’s implant advisory board member Dr. Randy Resnik on bone grafting for oral implantology. This article highlights the main concepts and materials related to grafting bone.
In order to be able to graft bone for implant health and support, various aspects of grafting science and adjunctive principles need to be understood.
It is important to understand bone biology, and the basic cellular process that occurs in bone. For example, through understanding the role of osteoblasts, osteoclasts, and osteocytes, the clinician can better visualize what is happening when a graft material is placed into a site and remodels into mature bone. Understanding bone biology also helps to gleam insight into how newer grafting concepts such as recombinant version of bone morphogenetic protein-2 (rhBMP-2) works. Dr. Resnik talks about this in his article and shows examples.
It is important to understand bone anatomy. Through understanding the different Misch division classifications of bone—D1, D2, D3, D4—including their respective hardness and where they are found in the mouth, many clinical decisions can be made. For instance, the posterior maxilla usually has soft D4 bone, where longer healing times and less osteotomy preparation is needed. From an anatomical standpoint, it is important for the clinician to clearly understand the anatomical landmarks of bone and the innervation points that are associated with them. This is especially true for more advanced grafting cases and sites. There are plenty of continuing education venues available covering these topics, including cadaver and grafting courses offered by the implant organizations, such as the American Academy of Implant Dentistry.
It is important to understand the available grafting materials and properties of each. There are various choices of grafting materials available and Dr. Resnik’s article spells out the choices of autografts and allografts very clearly. Every graft material choice is osteconductive, meaning it is a basic scaffold allowing bone cells to take over and grow bone. Allografts (donor bone) can be osteoinductive, meaning these help induce bone growth from surrounding bone. Only an autograft, a patient’s own bone, has osteogenic properties, meaning it can initiate bone growth on its own. Through understanding these principles, a clinician can choose the appropriate material, depending on the size of the defect. The handling properties of the various available materials have to also be taken into consideration. Whether the material is a particulate material or a putty creates a different clinical treatment for a grafting site. The handling properties of a material can also influence whether or not a membrane needs to be used. The purpose of a membrane is to exclude soft tissue and contain the graft material. For example, often times with some grafting putties, because of their rigidity and containment, a membrane is not necessary.
It is important to understand how to handle the soft tissue around a graft site and suturing techniques. An important aspect of bone grafting is getting closure of soft tissue around a graft site, and obtaining good keratinized tissue in the area. Even though bone grafting is about hard tissue, the surrounding soft tissue plays a large part of the graft’s success. Flap design, suturing techniques, and even soft tissue augmentation comes into play when grafting bone. It is beneficial for a clinician to be adept at manipulation of the soft tissue and suturing procedures, especially in more advanced bone grafting cases.
It is important for a clinician to utilize information from CBCT scanning technology. For many reasons, a CBCT comes into the picture when a bone graft is being treatment planned and done. From a medical/legal standpoint, a preoperative CBCT before grafting is done can offer ideal protection; with respect to visualizing variant anatomy, relating the graft to the prosthetic end point, and helping visualize the proposed implant position. While this may not be needed for a 5-wall extraction site defect, it becomes more important as increased walls of bone are missing. A postoperative CBCT scan done after the graft has healed is also important before placing implants so that the clinician can see the volume of bone generated, the quality of bone generated, and the final planned implant position.
This important area of implant dentistry, bone grafting, requires many considerations for success. While at first glance it appears to be a hard-tissue-focused discipline, for true success, a clinician needs to have an understanding of the following: the biology of bone; bone anatomy itself and the surrounding anatomy being grafted; the various materials that are available and properties of them; the soft tissue around the graft and how to handle the tissue and suture it; and be able to utilize CBCT scan information to tie it all together. Once these principles are combined, bone grafting becomes a real science and art for treatment success.
The role as a dentist to replace a missing tooth or multiple teeth involves an immense collaboration of information and skills. It is a large responsibility. As with any goal, a plan needs to be in place for successful execution. With respect to effectively replacing millions of years of evolution of human dentition, implant dentists need to take into consideration many disciplines of dentistry. To replace a tooth or teeth with dental implants in a dental practice, a dentist must understand the many surgical, prosthetic, and practice management areas of dentistry. These topics include occlusion, hard tissue considerations, implant positions, anatomical considerations, phonetics, appointment logistics for the patient, financial considerations for the patient, and more. This is what treatment planning is all about.
This month’s Implants Today article, by Dentistry Today’s implant advisory board member Dr. Craig Misch, is an excellent example of how treatment planning concepts come into play in the aesthetic zone. The aesthetic zone is one of the most demanding areas of the mouth to plan, place, and restore dental implants. All treatment performed in the anterior region is front and center stage with regards to aesthetics, soft-tissue contour, and function. Dr. Misch shows how— through a comprehensive assessment of a patient’s lip-line, bone level, soft-tissue condition, and more—a treatment plan based on a prosthetically driven approach can be made.
A large component of treatment planning, as Dr. Misch mentions, is incorporating a CBCT scan. A CBCT scan is imperative to ideally treatment plan for tooth replacement with implants. A CBCT plan offers information on anatomy, implant location, bone density, pathological conditions, and much more. Additionally, a CBCT scan offers ideal medical legal protection that is unparalleled by any other treatment planning modality. Combining a CBCT scan with a radiographic presurgical prosthetic template allows for a true presurgical plan based on the prosthetic end result.
A CBCT scan becomes even more important when a full arch of dental implants is being planned. The complexities of full-arch tooth replacement with implants are numerous, and a CBCT scan can help navigate these complexities and solidify a final plan. A prosthetically approved radiopaque denture used for a CBCT scan can offer invaluable information that relates the implant position to the final prosthesis. This prosthetic surgical relationship can also optionally be translated to a surgical guide that helps facilitate implant positions based on the planned prosthetic goal. A surgical guide can be used to facilitate implant placement with the guide directly through the guide sleeves, or the guide can be removed after initial osteotomy preparations and the implants can be placed freehand. I often use a guide for a full arch of implant treatment, but only use the guide for the initial implant osteotomy positions. I then remove the guide and place the implants freehand using the preplanned initial osteotomy sites. The initial osteotomy sites can then offer a direct guidance for either further osteotomy preparation and/or implant placement. Dentistry Today’s implant advisory board member Dr. Scott Ganz has termed this Template Assisted Surgery. Using this Template Assisted Surgery technique, I then have better tactile sensation to gauge the bone density and proceed accordingly. When a clinician spends the time to plan an implant case online, for instance, with a radiologist to create a surgical guide, this is the start of ideal prosthetically based surgical treatment planning. Once a treatment plan is created through this collaboration with a radiologist, options exist for the surgical execution of the plan. Also through this presurgical treatment planning, the clinician has the opportunity to commit to the final prosthetic end result. This could range from an overdenture to a screw-retained or cement-retained fixed implant bridge.
Lastly, an ideal treatment plan takes into consideration a patient’s needs and desires, and clinically fits the situation. To do this, a clinician must listen carefully to the patient, then educate the patient on the available options. At times, this sequence toward ideal treatment may involve staging phases of treatment because of financial considerations of the patient. An example of this is placing dental implants to support an overdenture, then at some point in the future converting that overdenture to a screw-retained fixed prosthesis. Treatment planning for dental implants is truly multidisciplinary, with one of the biggest challenges being how to provisionalize a patient during treatment. Only through understanding the patient’s lifestyle, needs, and desires, can the correct provisionalization sequence be chosen. The myriad of choices for treatment planning for dental implants can be made manageable for a clinician, when a defined treatment goal is determined, the patient is listened to, and a CBCT scan is used to implement that plan, either guided or nonguided.
|Michael A. Pikos, DDS|
Dentistry Today’s implant editor, Dr. Michael Tischler, interviews Michael A. Pikos, DDS
What are your thoughts regarding continued global dental implant market growth?
Dr. Pikos: A definite trend that we have been seeing involves continued global dental implant market growth as a direct result of increased patient demand for implant treatment, in addition to the increased number of restorative-based clinicians offering surgical as well as restorative implant services. These clinicians will need to seek out implant-based continuing education courses that will provide adequate surgical training to allow for safe patient treatment and predictable long-term results with minimal complications. Another driving force for increased revenue growth will be the advent of new dental implant technologies that will command higher prices. Finally, the largest demographic group—the baby boomers (born between 1946 and 1964)—is moving into middle age and later middle age. This group has been very instrumental in developing a youth-based culture, and now have a desire to maintain that youth.
According to the US Census Bureau, the United States alone has approximately 78 million baby boomers, which means that each year, more than 4 million Americans turn 60 years old. That’s 11,000 people each day, more than 450 every hour, and 100 every 13 minutes, every hour of the day until 2024. As a result, the market trend shows continued double-digit growth in the implant market.
Do you see a continuing demand for immediate full-arch fixed restorations?
Dr. Pikos: There is an increased public awareness now of the availability of full-arch immediate fixed restorations. Of course, these are provisional restorations to be followed by the final prosthesis some 4 to 6 months later. The 2 population groups that this treatment modality addresses involves both the edentulous arch patient, as well as the terminal dentition patient, many of which are true dental phobics who have not been to a dentist in a number of years.
There are many technological advances that have contributed to the predictability of these fixed full-arch immediate implant-supported restorations. These include advances in implant surface technology and aggressive thread design that accelerate healing times, in addition to abutment design and nature of the restorative material. Finally, the use of CBCT with third-party software allows for virtual treatment planning, as well as for the application of a fully guided surgical approach that includes the fabrication of a monolithic polymethyl methacrylate bar-supported hybrid prosthesis in advance of the surgical procedure to be used as a provisional prosthesis.
What advances in bone grafting do you see shaping the future of implant dentistry?
Dr. Pikos: Bone grafting in implant dentistry is critical to provide adequate 3-D bone volume for implant placement and long-term success of the implant abutment crown complex. That said, autogenous bone grafts remain the proverbial “gold standard” for bone regeneration as they provide osteogenic cells, osteoinductive growth factors, and an osteoconductive scaffold; all essential for new bone growth. However, autografts carry the limitations of harvest site morbidity and limited availability. As a result, tissue engineering has emerged as a technology to manage bone loss.
I have utilized rhBMP-2/ACS and rhPDGF-BB for the past 9 years with stable and predictable bone volume maintenance after loading. We will continue to see advances in tissue engineering and biomaterials that will provide appropriate tools to promote the migration, proliferation, and differentiation of bone cells, and to enhance bone graft healing. New strategies such as gene therapy, polytherapy by using scaffolds, growth factors, and stem cells along with the use of 3-D printing may offer new exciting options in the near future.
Do you see a trend toward increased training in virtual reality?
Dr. Pikos: The impact of virtual reality for the dental implant surgeon and his or her patient will be unprecedented in the near future. We are entering a world that will provide real-time, 3-D anatomic situational awareness with simultaneous interfacing with surgical planning, 3-D imaging, and technical/educational databases. The surgeon will be able to efficiently optimize real-time anatomical findings during surgery. As more advanced imaging technologies come online, interactive artificial intelligence programs will combine to monitor, direct, and assess operative progress and ultimately direct robotic surgical implantology applications.
The implications for surgical implant training are limitless. Quality control and 3-D visualization of the anatomic soft- and hard-tissue architecture as it relates to an optimal implant or regeneration protocol can allow repetitive virtual experience prior to actual patient surgery. Virtual surgical implant simulation, as in, “fly the mission before you actually perform the case” will become reality. Our new generation of experienced 3-D enthusiasts will be the dental surgeons of the future.
Do you see guided surgeries being used more as we head toward the future?
Dr. Pikos: I do see digital diagnostics, treatment planning, and guided surgery becoming the future standard instead of the present options. Indeed, sophisticated and successful full-arch prosthetic outcomes depend on careful computer-driven treatment planning and implant placement. This means that guides will be the norm. A full-arch implant-supported prosthesis, for example, is expected to be functional, extremely aesthetic, and hygienic. Anything less than precise preplanning and equally precise implant placement may result in a compromised final prosthesis. The smile-line, midline, and incisal edge positions must be correct. Screw access holes must emerge in the proper locations, especially in conjunction with tilted implants and multiunit abutments. Cantilevers and hygienic intaglio surfaces must be by design. There is simply no guarantee that a “freehand” placement of implants will allow for a predictable final prosthetic outcome, especially with full-arch immediate load prostheses.
Disclosure: Dr. Pikos reports no disclosures.
Welcome to the inaugural month of Dentistry Today’s dedicated implant section entitled Implants Today. As implant editor for Dentistry Today, my goal is to create a monthly venue based on a dedicated topic in implant dentistry. Editor-in-chief Dr. Damon Adams and I have assembled advisory board members who represent the best in implant dentistry. These advisory board members will be submitting articles in this monthly section throughout the year, adding their expertise to the topic at hand. Another goal of this section is to highlight pertinent continuing education venues for our readers, and also to involve relevant manufacturer partners who will introduce and advertise products that can bring greater success to your practice.
This month we are focusing on future trends in implant dentistry. We have Dr. Michael Pikos offering a brief but informative interview to share his views on this. As you read Dr. Pikos’ interview, it becomes clearly evident that the future of implant dentistry has potential for continued growth on many levels.
The demographics alone boldly indicate that the need for dental implants will increase due to the baby boomer segment of the population. This group is, better than any other, beginning to understand the advantages of dental implants and how they can benefit from this treatment. The years of evolution of dental implant science, thanks to pioneers such as my mentor, Dr. Carl Misch, and many other clinicians and researchers, have brought the success rate for dental implants to a level not seen when compared to other prosthetic replacements in the human body. This 95% industry-wide success rate often touted for dental implants has created a bold confidence for patients knowing that dental implants are here to stay as the foundation for tooth replacement. In my own practice, patients now present to us requesting dental implants; 20 years ago, it was an entirely different situation. This trend for increased acceptance for implants will only improve as the success rate increases even more throughout time. Now is the time to educate and involve more general practitioners in this exciting treatment arena to meet the increased patient demand.
We feel another trend for implant dentistry is going to be in making this ideal treatment modality more financially available for patients. There seems to be a slow trend of more insurance companies covering some implant procedures for patients, as compared to 5 years ago. This is most likely based on the widespread success of dental implants and the various prosthetic options. Our hope is that insurance companies see the long-term clinical benefits of implant treatment translating to actuarial decisions that further implant coverage for patients. Another avenue to enable patients to accept implant-based treatment are the various finance companies available. With the option of third-party financing, a patient can make payments over time, allowing the practitioner to be paid, minus a finance fee. When more complex and higher-cost treatment plans are presented, this outside financing, combined with maximizing a patient’s insurance benefits, often makes sense from a practice management standpoint.
A large part of implant dentistry’s success during the past 20 years has been on increased technology on many levels. The core technological success platform has been the advance of computer technology. Improved technology, advancements in educational venues, and communication have allowed for better sharing of knowledge within the implant field. This includes not only improved research available via the Internet, but also better audiovisual presentations and web-based venues that allow clinicians to present their knowledge. As Dr. Pikos points out in his interview, this trend will only continue as time progresses as education is leading toward virtual training.
Behind the future of implant dentistry will be the continued growth of CT imaging technology and integration with other adjunctive technologies that complement it. The merging of digital photo imaging with hard-tissue CT data that leads to prosthetically driven CT guides is an example of this merging of technology that is currently being used. This merging of technologies is furthered when prosthetically driven implant guides then lead to CAD/CAM milled prosthetics such as a zirconia implant bridge and other newer engineered nanoceramics and acrylics. The integration of accurate optical scanning of scanning jigs that create CAD/CAM milled abutments even further this entire digital workflow. The end result of this digital workflow is safer treatment with improved prosthetic success and predictability. As this improves, even greater success and predictability is expected in the future.
The future trends in implant dentistry, as a surgical and prosthetic part of dental treatment, are very bright. The demographics, proven success rate, financial treatment accessibility, and technological aspects that are available show a very positive trend. It will be interesting as we revisit this topic each September in this section to see how this trend continues. I look forward to this opportunity to steward this section and to share my passion for implant dentistry.
Implant Advisory Board