The angle and platform height at which an implant is surgically placed can be corrected through various implant manufacturers’ components as well as by using custom abutments. Some implant companies have angle corrections built right into the implant fixture itself;
however, these require more exacting placement positions.
This month’s Implants Today topic is implant fixtures and abutment considerations. The choice of how a final prosthetic solution attaches to the dental implant(s) involves various factors and is a fundamental concept in implant treatment. The 2 main considerations for an abutment choice are (1) the angulations or platform height of the implant(s) and (2) the soft-tissue height around the implant(s).
The final prosthetic option, as determined by a properly prepared treatment plan, should dictate the positions and numbers of dental implants to support that prosthetic decision. This is called prosthetically driven implant dentistry. The abutment that connects the prosthesis with an implant can address the variability of a patient’s hard- and soft-tissue anatomy and is the buffer between a prosthetic goal and the patient’s hard- and soft-tissue anatomy.
The angle and platform height at which a im-plant is surgically placed can be corrected through various implant manufacturers’ components as well as by using custom abutments. Some implant companies have angle corrections built right into the implant fixture itself; however, these require more exacting placement positions. Multi-unit abutments are a way to correct the angle of an implant, allowing the screw hole to be redirected. Multi-unit abutments come in various angles and heights. The disadvantages of using a multi-unit abutment include the following: an additional microgap, increased costs, and a connection with the potential to loosen. Ultimately, ideal surgical placement should be performed to create optimal implant platform heights and angles based upon the desired prosthetic outcome.
The tissue height around an implant is also the result of the surgical technique used and correct treatment planning. If the ideal tissue height cannot be achieved after hard- and soft-tissue grafting and manipulation, then abutments can be used to bring an implant platform to a more coronal position. Ideally, an implant platform should be 1.0 to 3.0 mm below firm keratinized tissue. When an implant platform is more than 3.0 mm below the keratinized tissue, there is an increased propensity for soft-tissue problems and more pain with prosthetic try-ins. Ideally, it is better to achieve the correct platform height by employing correct surgical procedures than to gain that height through prosthetic parts (such as a tall multi-unit abutment).
In this month’s issue of Dentistry Today, we have a cover-featured article by Implants Today Advisory Board member, Dr. Jack Piermatti. Dr. Piermatti expertly discusses the details of different abutment choices in implant dentistry. Dr. Daniel Drake has contributed an article on the latest technologies in implant dentistry. Lastly, our editor-in-chief Dr. Damon Adams and I would like to announce the addition of Drs. Charles Babbush, Paul Fugazzotto, and David Little to our distinguished list of Implants Today Advisory Board members.
Also in Implants Today
Listening to Carl lecture was not only educational but entertaining. He was humorous, answered questions quickly and accurately, and always exhibited total confidence. Every time I heard Carl lecture, it was always a different experience, even when the topic was the same. He was a gifted orator who made learning fun.
So many of our lives have been positively affected by Dr. Carl Misch’s presence on this planet. His passing early in January was a great loss to our profession and many will miss him dearly. I will remember Carl for the incredible positive impact he made on my career and in my life. I know I am not alone in feeling this way, because he had such an influence on so many of my colleagues and their patients. Carl exemplified focus, commitment, and passion for not only implant dentistry but also for dedication to excellence in life.
As I look back on his accomplishments during his 69 years, the breadth of his work is nothing short of amazing, with a CV that could be a book itself. Carl was a prosthodontic specialist with an implant certificate and master’s degree from the University of Pittsburgh School of Dental Medicine. The Misch International Implant Institute has educated more than 4,500 dentists and has been the primary educational venue for 6 dental school specialty residences with an ongoing physical presence in 9 countries. As a Fellow of the Misch International Implant Institute, I can personally say that this is one of the best educational venues for surgical and prosthetic dental implant training available anywhere. The reason, I feel, that the Misch Institute is so successful is the consistent principles that are taught, all based on Carl’s benchmark textbook Contemporary Implant Dentistry, now in its third edition, and on his book Dental Implant Prosthetics, now in its second edition. Contemporary Implant Dentistry has been published in 9 languages and is the go-to reference book for students taking their fellowship and diplomate exams with the International Congress of Oral Implantologists and American Academy of Implant Dentistry. Carl was also politically involved, honored, and a leader in all the major implant organizations.
Carl was not only an educator at his institute but was also a clinical professor and director of oral implantology in the department of periodontology at the Maurice H. Kornberg School of Dentistry at Temple University. Beyond that, Carl had lectured in every state in the United States as well as 47 countries. Listening to Carl lecture was not only educational but entertaining. He was humorous, answered questions quickly and accurately, and always exhibited total confidence. Every time I heard Carl lecture, it was always a different experience, even when the topic was the same. He was a gifted orator who made learning fun. In 2004, I had the honor to co-author with Carl one of his 250 articles, which was published in Dentistry Today.
I first met Carl in 1999, and when he signed his textbook and wrote “let the force/area be with you,” I knew I had met a special person. Eighteen years later, I can say my life has been enhanced by his presence on this earth and I will miss my mentor and am grateful for his gifts to all of us.
Dr. Damon Adams, our editor-in-chief, and our editorial team, who have all worked with Carl on numerous articles published in Dentistry Today, will sincerely miss this true icon in dentistry.
Article By Dr. Misch
The aesthetic zone represents the center stage for implant placement. This is true in a patient with a high lip-line when smiling as all aspects of implant treatment are immediately visible to the patient and all others who may interact with the patient. Treatment in the aesthetic zone is even more scrutinized than other areas of the mouth.
This month’s Implants Today focuses on dental implants in the aesthetic zone. The aesthetic zone represents the center stage for implant placement. This is true in a patient with a high lip-line when smiling as all aspects of implant treatment are immediately visible to the patient and all others who may interact with the patient. Treatment in the aesthetic zone is even more scrutinized when compared to treatment in other areas of the mouth. For example, the steps for provisionalization are a crucial aspect of treatment since the type of provisional and shape of the provisional can help set up the emergence profile of an implant site.
Implant Site Development (March 2012, Wiley-Blackwell) by Drs. Michael Sonick (an Implants Today advisory board member) and Debby Hwang covers the concept of setting up sites for implant placement in depth. It also includes chapters by other prominent experts, such as Drs. Craig Misch and Scott Ganz (also advisory board members). I recommend this textbook because site development is so important; just like constructing a building, each foundational step sets up for the success desired in the final result.
The multidisciplinary topics that must be taken into account with implant treatment in the aesthetic zone include but are not limited to: soft-tissue site development, vertical and horizontal bone augmentation concepts, socket preservation materials, immediate versus delayed placement, the role of a CBCT scan, growth factors, provisionalization options, emergence profile and abutment considerations, soft-tissue biotype assessment, and implant spacing and depth. This is a true merging of surgical and prosthetic principles, as treating a patient for tooth replacement in the aesthetic zone requires a sound understanding of many principles that must come together for success. This is why I personally enjoy implant dentistry so much—there is so much to know and implement clinically. When you approach treatment with this kind of respect, treatment becomes a true passion as a clinician. Our patients’ lives are being changed and everyone benefits. This is certainly an endeavor worth pursuing!
While the principles for implant treatment success in the aesthetic zone are used in other areas of the mouth, the anterior region mandates that almost every principle be used. As Dr. Carl Misch said, “Don’t place your first implant on a central incisor in a patient with a high lip-line!” Learn dental implant principles in less demanding areas of the mouth while building expertise and clinical skills. Lastly, don’t just read and watch; step in and do it! The best way to learn is to do and to experience.
This issue presents an outstanding article by Dr. Michael Sonick et al that sums up the many aspects of success mentioned here. Also, Drs. Todd Schoenbaum and Chandur Wadhwani contribute excellent content that focuses on the screw-retained versus cement-retained restorative options in the aesthetic zone, and Dr. Dino Javaheri presents a simplified chairside technique for both temporary fabrication and impression taking.
We would like to focus on the various CBCT-generated implant guides that are available and look at their advantages and disadvantages. A CBCT-based implant guide is a state-of-the-art concept that represents the highest aspects of implant technological advancements.
This month’s section revisits guided implant surgical applications, a topic that will appear in each December issue. We will focus on the various CBCT-generated implant guides that are available and look at their advantages and disadvantages. A CBCT-based implant guide is a state-of-the-art concept that represents the highest aspects of implant technological advancements.
Of the 3 categories of guides available, tooth-supported guides for quadrant implant dentistry is the most predictable and simple of the guided implant scenarios. A tooth-supported guide has little room for error, as it is a hard-tissue-supported guide that is supported by teeth that are visible and accessible. This is different than a bone-supported guide, which is more complex surgically and more involved to create.
Soft-tissue-supported guides for full-arch implant dentistry are appropriate when the final full-arch implant-supported prosthesis does not required alveoloplasty. If alveoloplasty is required for prosthetic thickness or to hide the prosthetic smile interface, then a bone-supported guide is needed. A soft-tissue-supported guide can be used when extractions are being done concurrently at the time of surgery, but extractions can create complexities with a soft-tissue-supported guide. An example of extractions causing a complexity with a soft-tissue-supported guide is if extractions cause the ridge shape to change during the process, rendering an inaccurate fit of the preplanned guide on the ridge.
Bone-supported guides for full-arch implant placement are by far the most technically advanced guide in both the presurgical planning and during the procedure itself. Bone-supported guides in full-arch treatment require that aggressive flaps be done in order for the guide to fit. When extractions are being performed, in addition to alveoloplasty, the complexities are furthered. In the situation of extractions and alveoloplasty, these full-arch guides are either stackable guides or multiple guides. These advanced guides are, in general, associated with higher costs for the doctor and require more time to plan and have delivered to an office.
Another scenario that has become more popular as technology has improved, are the dynamic navigation systems based on motion tracking technology. There are a few systems available now for this that are FDA approved. The concept is to take a prosthetically driven plan from a CBCT scan, and then place the implants in the correct position freehand with the assistance of an on-screen program guiding with precise feedback. While there is a learning curve with this technique, the concept certainly offers some exciting potential.
Implants Today advisory board member Dr. Randolph Resnik offers an excellent article that exemplifies many of the points I presented here. Randy’s dual-scan technique shows an accurate way to represent the prosthetic end result on a CBCT scan. As time goes on, guided-implant surgery and its related technologies will become even more innovative.
Also featured this month, Dr. L. Stephen Buchanan addresses today’s need for general practitioners to learn how to start placing and restoring dental implants in their own office.
Also by Dr. Michael Tischler
Everything related to implant dentistry involves a strong understanding of human craniofacial anatomy. To treatment plan, a clinician must have knowledge of anatomical concerns such as the sinuses and the locations of the mental foramens, the incisal foramen, the mandibular nerve....
November’s Implants Today topic is bone grafting for implant placement. If you are a dentist focusing on dental implants as a treatment modality, then bone anatomy, bone physiology, and bone grafting should be understood on every level. Every aspect of implant dental treatment—from treatment planning and surgery to prosthetics—is dependent upon the clinician having adequate knowledge about bone science. Even a medical history review is related to understanding many things about bone science. An example of this is the relationship between the osteoporosis drugs (bisphosphonates) and the risks of osteonecrosis. Understanding the science behind why there is a risk with respect to how bisphosphonates work, allows for an optimal medical history review and improved treatment planning with the patient. This is just one example of many that justify the importance of a good understanding of bone science on the part of the clinician who places implants.
Understanding Bone Anatomy and Physiology
It is important for the clinician to have a strong of understanding bone anatomy and physiology. Everything related to implant dentistry involves a strong understanding of human craniofacial anatomy. To treatment plan, a clinician must have knowledge of anatomical concerns such as the sinuses and the locations of the mental foramens, the incisal foramen, the mandibular nerve, the infraorbital foramens, and much more. As I reference in many of these editorials throughout the year, a CBCT scan is imperative for the true understanding of anatomical relationships and pathology. The patient’s anatomy dictates both bone grafting and implant placement surgery. Understanding bone physiology is also important. When placing a bone graft material into an extraction site, or to graft the lateral wall of a ridge, the clinician should understand the physiological process that is happening at the site. Through understanding the actual process, the clinician can make the right surgical and grafting material choices. When a clinician chooses a graft material, that choice should be based on the size of the defect. The larger a defect is, the more osteoinductive properties a graft should have. Through understanding that defects with less walls of bone have less vascularity, the choice to use autogenous or an alloplastic bone would be made. This shows how knowledge of both bone anatomy and bone physiology is important and how they both interrelate.
Grafting Quadrant Dental Regions
Not only is gross anatomy important, but understanding the soft- and hard-tissue anatomy of different regions of the mouth is as well. An example is the anterior maxillary region versus the posterior mandibular region. The anterior maxilla is the most demanding area to graft in the mouth. If there is 2 mm of papilla loss in a patient with a high smile-line, it could affect the entire case. That 2 mm of papilla height loss can be associated with extraction technique, implant spacing, soft-tissue concerns, and more. Successful bone grafting is also related to knowledge of prosthetics. In the anterior region, ovate pontics at the time of grafting can create improved hygiene and aesthetics.
The posterior regions of the mouth create challenges other than aesthetic concerns. In the maxillary posterior region, the sinus is the main concern and how to manage it when grafting. Both lateral wall sinus grafts and osteotome lifts are common ways to graft for implant placement. These could occur during implant placement or may be staged before, depending on the case. In the mandibular posterior regions, the mandibular nerve is the dictating factor. In general, both the maxillary and mandibular regions are anatomically wide due to the ridge size. The width of the ridges affects the choice of graft materials and membranes that might be needed. As with all bone grafting, the blood supply is an important consideration.
Grafting in Relation to Full-Arch Treatment
When a full arch is being treated for tooth replacement, the considerations are different than with quadrant grafting and implant placement. The prosthetic choice for the full-arch treatment plan dictates the grafting protocol. If the treatment plan is for a screw-retained prosthesis that has pink gingiva (Misch fixed prosthesis 2 [FP2] and FP3) then, more than likely, the clinician will be reducing the height of bone and grafting in any extraction site defects. This is because adequate prosthetic height is needed and in the maxilla the high smile-line should hide the gingival prosthetic junction. When the prosthesis doesn’t require a pink gingival area (Misch FP1), then bone is not taken away but instead grafted to be maintained or increased. Different prosthetic choices dictating the grafting treatment plan.
This month, Implants Today advisory board member Dr. Craig Misch presents an outstanding article that shows how advanced the science of bone grafting has become. Craig is both an oral surgeon and a prosthodontist, and as a dual specialist, his article brings out many key concepts that are involved with bone grafting and implant dentistry. The tissue engineering advancements that he presents, tied in with advantages of an autogenous bone block, show a true blending of concepts. Between what has been presented above, and the excellent content of Craig’s comprehensive article, the reader can begin to grasp how successful interdisciplinary bone grafting is.
Also this month, Dr. Ahmad Soolari and Mr. Amin Soolari exemplify the principles of the need to graft bone to support implant placement. This article also shows the clinical choices of grafting materials, membranes, and the timing of an implant case.
More From Implants Today
Treatment planning is about communicating treatment recommendations clearly to a patient. Unless the doctor and team are united in a common direction and culture, the many facets of presenting a treatment plan may not appear to be coordinated, and therefore, will not be as effective to a patient.
This month’s Implants Today topic is treatment planning for implant dentistry. Of all of the topics we revisit each year, treatment planning is the most important, since it requires a combination of practice management and clinical disciplines. It is the starting point of many things that affect our patients’ lives.
THE IMPORTANCE OF A MISSION STATEMENT
When a dentist treatment plans an implant case, whether it is one implant or an entire arch, there are many clinical decisions and core individual philosophical opinions behind the plan. I believe a clinician should have a core practice vision, also known as a mission statement, that backs up any presented treatment plan. This vision statement defines the goals and culture of the dental practice, and from that vision statement, all interactions with a patient are driven. The reality is that most dental practices do not have a written vision statement. The reason for that is perplexing, as the concept of setting goals, writing them down, and committing to a vision statement is recommended in almost every New York Times best-selling leadership and business book. As dentists, we are running a business, and the core philosophy of having a vision statement for your dental practice for success is ubiquitous to all businesses.
A mission statement is not just about the bottom line of your practice. It is about representing your personal vision as a committed statement that affects your employees, your treatment decisions, and ultimately the business as a whole. I believe patients can sense the culture of a dental practice when they first call the office and again once they arrive. The vision statement and practice culture sets the tone for everything that occurs in a dental practice. Think about the vision and culture of the Ritz Carlton Hotel chain, or Lexus as a car manufacturer. These companies are both committed to excellence, and everything that they do, from their products to customer services, represents their vision and mission statements. Their visions create choices such as the quality of the towels Ritz customers touch to the leather the Lexus customers sit on. As a dentist, having a defined vision will translate to the front desk employees’ communication skills, to the efficiency of clinical care, and even to the quality of materials a doctor chooses to use on his or her patients. I believe that without a strong vision statement, treatment planning will not be as effective. Treatment planning is about communicating treatment recommendations clearly to a patient. Unless the doctor and team are united in a common direction and culture, the many facets of presenting a treatment plan may not appear to be coordinated, and therefore, will not be as effective to a patient.
Treatment Plans Solve Problems
Our patients usually come to us with a problem needing a solution. The problem could be replacing failing teeth or replacing missing teeth. We are honored with that responsibility and should appreciate the vulnerability of our patients’ feelings as they come to us for help. There are many subliminal background factors involved when we communicate our treatment plans with the goal of a patient accepting and also affording that treatment. A vision statement, which is put in writing and committed to, is the backdrop behind the implementation of every treatment plan given to a patient. When presenting a treatment plan, there are many facets to consider: clinical decisions, material choices, staff involvement choices, technology choices, and office environment choices that directly affect your patient’s life. Behind all of those components are marketing decisions for your practice that help bring that patient in for treatment. Again, I recommend that every dental practice, whether an implant-focused one or not, define their practice with an individualized, written vision statement that incorporates the identity of the practice and owner’s core beliefs.
A practice vision statement affects many aspects of attracting patients and treating them. This starts from the first contact a patient has with a dental practice. This could be the front desk staff or an advertisement a patient may have seen. A vision statement of excellence, appointed by the leader (owner) of the practice that a staff collectively commits to, will affect the decisions that shape advertisement choices and staff dialogue that helps a patient choose a dental practice for his or her treatment. This vision statement also affects the patient’s experience after arriving at the practice.
A vision statement might incorporate a focus of providing the latest technology in a practice. That commitment directly affects the quality of treatment. I have often highlighted the important role of technology with respect to ideal implant treatment in these monthly Implants Today introductions. Choosing the latest technology is based on core choices. This directly affects treatment planning. For instance, having an in-office CBCT machine has many benefits to both treatment planning and actual treatment. In my practice, I see a higher treatment plan acceptance rate since we often take a CBCT at a patient’s first implant treatment visit. By doing this, I feel a patient shows his or her level of commitment to treatment, as well as my commitment to being current and state of the art. This means a lot to patients, as they are making financial decisions and are feeling vulnerable.
Core practice visions should also incorporate scheduled communication between staff and the practice leaders. When a dental team is well coordinated with respect to communication of a proposed plan and practice values, there are many benefits. First, the patient is more likely to accept treatment. Beyond that, all informed consent forms are adequately presented, the financial arrangements are clearly communicated, and in the end, there is increased medical legal protection and reduced problems as a case is planned.
Standard operating protocols (SOPs) should be established with all aspects of patient communication and treatment. A leading dental consultant, Dr. Bill Blatchford, often recommends checklists similar to what an airplane pilot does. SOPs and good staff communication through scheduled meetings, as well as defined coordinated staff roles, creates an ideal treatment plan presentation for a patient. I have found, once again, in my practice that presenting implant cases and following up on the plans are best done with a team. My practice incorporates a philosophy of having me, as the implant surgeon, build trust and confidence with the patient, then having my clinical assistants and financial treatment coordinator follow up with the details. It makes sense from a practice management standpoint. None of this happens by chance; it has to be preplanned through core practice vision commitments.
This month, one of our Implants Today advisory board members, Dr. Scott Ganz, presents an article entitled “Enhanced Diagnosis and Treatment Planning for Implants.” This article exemplifies the principles outlined in this introduction by demonstrating how a commitment to excellence in technology and continuing education translates to ideal treatment planning. Scott’s commitment to providing the absolute highest level of CBCT-based treatment results in his patients receiving the best care possible. This month’s other offering under the topic of implants is by Dr. Rick Winter et al and describes a multidisciplinary case that demonstrates how to treat a patient with a severely atrophied mandible, vastly improving the patient’s function and self-esteem.
If you hoped to read this introduction and see more clinically based treatment planning steps, then I might have disappointed you. My intention was to use this venue to share core concepts behind those clinical steps. Our goal as implant dentists is to provide clinical excellence; however, without a core plan to communicate those clinical steps, financial steps, appointment steps, follow-up hygiene steps, etc, those clinical steps may either not be chosen by the patient, or miscommunications could hamper a great treatment experience for the patient, thus creating possible subsequent patient relation issues.
In summary, treatment planning is done from a core practice vision that is created by the clinician as a leader of the practice. As a leader who has created a solid written vision, your treatment team will then help your patients who are looking for the best solutions to their clinical problems get the ideal treatment they deserve. Treatment planning, as I have laid out, involves so many things. Under your direction and leadership, everyone involved, from the team to the patient, will benefit.
Also From Implants Today
As clinicians, we are replacing teeth that have evolved and changed throughout thousands of years. Maxillary molars, for example, have 3 roots instead of 2, because the bone is softer and the forces are greater in the posterior of the mouth.
It has already been one year since the Implants Today section was first published. I want to thank Dentistry Today’s editor-in-chief, Dr. Damon Adams, for the invitation to be the editor of the implant section and for fostering a shared vision between us for this exciting new content. The support and encouragement of the entire editorial team and the positive feedback from our readers are also very much appreciated. I would also like to acknowledge and thank all the members of our world-class Implant Advisory Board who, during the past year, have contributed excellent and clinically relevant articles aimed at the GP reader. It takes dedication and a lot of time to write a quality clinical article and, through those efforts, Dentistry Today has been able to offer an abundance of solid information this past year that should have the potential to make a positive impact on your practices and patients. Damon and I would also like to encourage our clinician readers to submit implant articles to Dentistry Today for editorial review and, if accepted, publication. When our readers and colleagues contribute interesting clinical case report articles, a culture of shared knowledge is created. It is this concept of shared knowledge upon which our editorial content in Dentistry Today was founded.
The “Future of Implant Dentistry” was the inaugural topic last September. This, along with the other 11 topics that were covered throughout the year, will be revisited each year. By revisiting the specified topics that cover the many aspects of implant dentistry, a fresh annual retrospective can be realized. Implant dentistry is an evolving discipline and, through re-examining, these same well-rounded topics and fresh perspectives can be presented. With our potentially content-rich topics, such as guided implant surgery, implants in the aesthetic zone, implant overdentures, cone beam CT (CBCT) for implant dentistry, and 8 other exciting implant-related topics, new information will be updated and discussed each year.
The future of implant dentistry continues to be exciting, evolving, and more predictable. The dental implant industry a billion-dollar enterprise that is supported by improved materials, technologies, and various clinical procedures every year. I would like to look at the future of dental implant treatment with the grounding perspective of first looking at the past. As clinicians, we are replacing teeth that have evolved and changed throughout thousands of years. Maxillary molars, for example, have 3 roots instead of 2, because the bone is softer and the forces are greater in the posterior of the mouth. Cuspids have longer roots to support the forces of occlusion in extrusive movements. Through this historical and evolutionary perspective, one can appreciate any future progress with dental implants with respect of the daunting task and responsibility at hand. Dr. Carl Misch has been speaking on this perspective for many years. The future of successfully replacing what nature has created—and then sometimes fails—with implants requires the latest technologies, techniques, materials, and continuing education (CE).
As computer technology advances, there is a direct impact on implant dentistry and the potential for increased success. There are a growing number of companies that offer CBCT machines and software planning programs. Better resolution, faster scans, and the availability of virtual planning are examples in the arena of technology improvement. More sophisticated Internet technology at higher speeds has allowed clinicians and laboratory teams to share treatment planning information and to foster better collaboration among clinicians as well as those professionals representing different specialties who work together on the patient’s behalf. CBCT scanning and associated CAD/CAM technologies can now be used to plan and mill an entire case, with digital files following the surgical positions all the way to the provisional and final prosthesis. This is true for both quadrant implant dentistry and full-arch replacement teeth. The technological advances to measure the initial and post-integrated stability of dental implants have also impacted the success of treatment. The Implant Stability Quota (ISQ) measures the true bone-to-implant contact, as opposed to the perceived torque value. Through having an ISQ reference number, clinical loading decisions can be made with an objective value behind them. This information is especially useful for decisions related to immediately loaded implants.
Intraoral scanning technologies have evolved to a level that can totally replace manual tray impressions with dental implants. A digital scan of an implant requires an appropriate impression coping that correlates to the appropriate implant system library. Currently available scan copings are affiliated with closed systems specific to an implant company. In the future, open digital impression systems will allow for more dentists to utilize this technology. Once a digital intraoral impression is made, that information can be used to design a custom abutment, the provisional, and final crowns. Through digital intraoral scanning, the entire workflow can be digital with great accuracy. Models that are either CAD/CAM milled or 3-D printed can be used. The availability of chairside box scanners allow a clinician to scan a prosthetically approved full-arch bridge provisional so that a zirconia duplicate can be milled as the permanent restoration. Box scanners have substantially reduced in price and size of the units, making them easier for clinicians to obtain.
Surgical and prosthetic techniques for implant dentistry are closely related to technological advances as well as materials and CE. When a clinician adapts a new technique for implant treatment, it is often tied into advancements in other areas of implant dentistry. Immediate loading of dental implants is an example. Through advancements in implant design, and the availability of measuring implant stability with an ISQ reading, immediately loaded implants have become more predictable. As immediate loading becomes more mainstream, there will be more case studies upon which to grow our knowledge base, then to share that information through educational venues.
Another example of a technique that is based on technology is the increased use of growth factors in everyday implant treatment. Years ago, it was expensive and cumbersome to obtain platelet growth factors. Now, via technological advances and the ability to share information, platelet-based growth factors, such as platelet-rich plasma and fibrin, can be obtained and processed in a simple and inexpensive manner. Many other techniques are trending with the advancement of implant dentistry: conservative sinus grafting techniques, extraction techniques, soft-tissue grafting, and hard-tissue grafting are all areas that have evolved and will continue to do so, from technology, materials, and advancements in education.
Implant dentistry is a material-oriented discipline. From the implant itself to prosthetic parts, materials impact the success rates of implant treatment. In the past few years, there has been a trend toward innovative implant designs to help stabilize hard and soft tissue around implants. There are more choices from implant manufacturers as far as different heights and widths of implants. Manufacturers have offered an increase in shorter implant options in the past year, due to material designs and time-tested proof of success in the industry. Materials are also partially dictated by demand, with manufacturers listening to trends in the industry.
Zirconia continues to increase in the implant industry as a material for both implant design and prosthetic options. There are now 2-piece zirconia implants available allowing for 2-stage options and increased clinical applications. Major implant companies are also starting to create zirconia implant options, showing a trend and a real presence of increased use of zirconia in the implant world. CAD/CAM technology, which has led to the creation and use of zirconia implant bridges and crowns, continues to grow. In addition, there is a trend toward increased acceptance of zirconia, as this material shows continued success as a prosthetic option. There is also an increase in the use of 3-D printing for provisionals and models, as this technology has demonstrated increased accuracy during the past few years, while becoming more affordable. This also ties into the trend of a total digital workflow. There is even a milled-then-sintered metal option that is awaiting US Food and Drug Administration approval and should be available soon. This would further simplify designing and creating metal bars for smaller laboratories.
The collaboration of clinical experience based on technology, materials, and techniques is really what the future of implant dentistry is grounded upon. The sharing of information in journals, courses, and online is where true growth in this industry occurs. With digital technologies advancing, this will become even more prevalent and will assist the growth and success of implant dentistry as time goes on. Webinars, online planning sessions, and live online telecasts are just a few venues available for implant education. The many online education groups such as Dental XP and VuMedi offer thousands of hours of CE that were not available just a few years ago. Technology has also increased the quality of these presentations, allowing for an even higher level of quality education. Online planning and case sharing are also becoming mainstream, even furthering treatment planning collaborative efforts. All of this exchanging of information will propagate growth in the implant field, and I believe this will exponentially increase as time goes on.
This month, Implants Today Advisory Board member Dr. Natalie Wong’s article exemplifies the future of implant dentistry and how the collaboration of technology, materials, and techniques can create excellence in dental implant treatment. The guided case presented truly shows how advanced the industry has become, where a digital plan is physically implemented based on milled guides and a pre-created provisional restoration is delivered at the time of surgery.
It is from the publication of excellent cases like these that clinicians from all over the world can share and learn about the latest technology, techniques, and materials to further advance the future of implant dentistry. Here at Dentistry Today, we envision this collaboration of science and technology only increasing and leading to even more predictable implant treatment for the future.
Also from Implants Today
Since its invention and the ability to look at the human body in a 3-D perspective, advancements have made it practical for clinicians to either own a CBCT or have access to a mobile CT unit. Scan times and radiation levels have decreased, making CTs safer and more practical to have in a clinical setting.
This month’s Implants Today topic focus is on cone beam computed tomography (CBCT) planning for implant dentistry. In 2012, Implants Today Advisory Board member Dr. Scott Ganz and I authored a 3-part article series in Dentistry Today entitled, “The CT-Based Team Approach to Care” (Part 1, Part 2, Part 3). This series discussed how treatment planning, surgery, and prosthetics relate to a CBCT scan and the team approach. I bring up that article series to remind us how important CBCT has become for every aspect of implant dentistry including treatment planning, surgery, and prosthetics. In the time since the its inventors, Hounsfield and Cormack, received the Nobel Prize for Medicine in 1979, CT technology has greatly impacted implant dentistry and is a large part of the current success with dental implants.
Since its invention and the ability to look at the human body in a 3-D perspective, advancements have made it practical for clinicians to either own a CBCT or have access to a mobile CT unit. With multiple CBCT companies in competition with one another, the scan times and radiation levels have decreased substantially and the size of the CT units have all decreased during the past 37 year as well, making CTs safer and more practical to have in a clinical setting.
TO BUY OR NOT TO BUY?`
I am often asked for advice on which CBCT machine to purchase, and if a practitioner can support the costs involved and realize a decent return on investment (ROI) from the CBCT equipment. Choosing the right CBCT machine for a dental practice is a decision that mandates investigation of the style and size of the unit, ease of operating features, cost, associated software, and how fast the unit could be serviced, if needed. These are all somewhat subjective considerations, dependent on each clinician’s situation. Only after through research can that decision be made; doing this research will educate the clinician on many levels to ensure that the right choice has been made, making it easier to introduce this new technology into the practice and to patients.
So, how does a clinician know if a practice can financially support a CBCT machine, or if it would make more sense to utilize a mobile CT unit that comes directly to the dental facility after making an appointment? The answer to that is based upon various considerations, with the most important being: “Where does the clinician want to be in a year or so, from a vision standpoint?” If one has a vision to do more implants, and the clinician has the skills to perform implant dental treatment, then an on-premises CBCT machine has a high potential to make a positive ROI. One should know that the ROI for a CBCT machine is not calculated as simply as how many CT scans are being taken and how much a clinician is being paid for the scan itself. The immediate information to which a clinician can have access, and discuss with a patient by having a CBCT machine right on premises, offers many benefits that are sometimes overlooked when looking at ROI. As an example of the efficiency brought to the table by having this technology readily available, a CBCT can be taken on a new patient and the clinician can then review the information and offer a treatment plan at the first visit. It is not only impressive to the patient but also offers a large convenience factor. In my practice experience, having an on-site CBCT has led to an increased treatment acceptance rate.
There are other clinical advantages that can make having an on-site CBCT a good choice. In my practice, we often take a post-extraction CBCT before immediate implant placement, either in a full arch or in a quadrant. Having a CBCT machine on the premises allows for immediate placement of implants with CBCT guidance. Although a mobile CBCT unit could provide the same result, it would be logistically more cumbersome. Another clinical advantage of an on-site CBCT are follow-up CBCT scans on bone grafts, pathology, and complications. Having an on-site CBCT for these purposes offer many advantages to a practice.
CBCT Scans Routinely in Implant Dentistry: The Standard of Care?
In my opinion, a CBCT scan should become the standard of care for implant placement. There is not yet a full consensus among dental implant experts that use of a CBCT in implant dentistry is the standard of care. While many dental implants can be placed successfully without a CBCT scan, if there is a complication, a clinician could be asked why a CT was not taken. There is really not a defendable answer, since mobile CBCT units and other CBCT machines are now so readily available. I simply do not believe a clinician should take the chance of delivering implant dentistry without the detailed information that CBCT technology provides.
Furthermore, I also believe that there is no area of the mouth of which a clinician can justify that a CBCT should not be taken. The inferior alveolar nerve in the posterior mandible can be identified in CBCT software programs so that it can be properly avoided. A CBCT scan in the posterior mandible can also identify the angulations of the lingual wall so as to avoid perforations. The information offered in the CBCT scan can be utilized with either a guided or nonguided approach. In the posterior region of the maxilla, a CBCT scan can offer information to the location of the sinus wall, allowing the clinician to utilize osteotomes or lateral wall grafting, as indicated. In the process of making the most educated decisions possible, a panoramic radiograph does not offer the detailed information that CBCT technology provides. The anterior mandible presents many challenges that a CBCT scan can help navigate. A CBCT scan in the anterior mandible can not only help avoid lingual cortical plate perforations, but can also help prevent many other prosthetic and surgical complications. The anterior maxilla offers many challenges for the clinician, as the final prosthetic result is visible in most cases, depending on the patient’s smile-line. Bottom line? Having a CBCT scan for evaluation in the anterior maxilla can help avoid a multitude of prosthetic and surgical complications.
Professional Evaluation of the CBCT Scan
Once a CBCT scan is taken, I recommend that an evaluation of the CT scan is done with a formal report by a board-certified radiologist. It once again negates any risk of missing pathology on a scan that one, as a clinician, is (or may be) responsible to see and relay to a patient. After utilizing radiology reports as a standard for many years, I have seen many pathological situations that I would not have found on my own. These include carotid artery blockages, tumors and cysts in the cranial area, airway issues, vertebral pathology, and more. The minimal fee for the radiology report is justified in my opinion, and it is a real plus simply for peace of mind. Most dentists are not educated enough in the arena of radiological findings and interpretation to match the training and knowledge of a radiologist.
DICOM Data: CBCT Software Programs
The Digital Imaging and Communications in Medicine, or DICOM, data from a CBCT scan must be read by a CBCT software program for planning and diagnosis. Most CBCT companies have a resident software program that is part of the CBCT purchase. There are also independent company software CBCT programs that are more robust than standard software programs and come with a CBCT purchase. These “after-market” programs that read the DICOM data can offer advantages such as accurate anatomic implant placement on the program, advanced nerve mapping, improved detail 3-D mapping of prosthetic structures, portals to order surgical guides, and more. It is an advantage for a clinician to be able to utilize the CBCT software program in planning an implant case. Adept utilization of a CBCT program allows the clinician to offer a patient valuable and immediate information.
It is clear that CBCT scans are the backbone to successful dental implant treatment. I find this topic extremely important in the realm of implant treatment. CBCT scans offer an advantage to success for implant placement in every area of the mouth, for single implant placement or full arch and for bone grafts. As a clinician involved with implant dentistry, I recommend you embrace this technology that is safe, accurate, and offers a substantial tool toward successful implant treatment for patients.
This month, we have selected exceptional implant articles for our readers. Dr. Ara Nazarian presents a full-arch cement-retained zirconia implant case in which CBCT information played a vital role. Ara utilized information/data from CBCT scans to create 3-D models and surgical guides. The process that he showcases demonstrates the ultimate in the utilization of the CBCT process using digital technology to ensure a predictable prosthetic success.
Implants Today Advisory Board member, Dr. Michael Scherer, also presents an excellent article that shows how a CBCT scan can be used to plan for an overdenture case. This further shows how CBCT scans translate to success when executing both removable and fixed implant prosthetic options.
I have also authored an article on CBCT scans related to full-arch implant restorations. This article incorporates many of the principles mentioned in this section and it is my hope that it helps stress the points introduced above in this month’s introduction to Implants Today.
Also From Implants Today
When clinicians present the available treatment options to patients, they must be able to convey the process of how that case will be provisionalized. The type of provisional and how it will affect a patient’s lifestyle during treatment is often a part of whether or not a patient accepts a treatment plan.
This month’s topic is Provisionalization for Implant Dentistry. This is, in my opinion, one of the most important topics that Implants Today covers throughout the year. How an implant case is provisionalized should be one of the first treatment planning and clinical decisions made. The method and timing of provisionalizing an implant case affects not only a patient’s lifestyle during the implant healing period but also the clinical success of the case.
The method of provisionalization needs to be known early on when treatment planning an implant case. When clinicians present the available treatment options to patients, they must be able to convey the process of how that case will be provisionalized. The type of provisional and how it will affect a patient’s lifestyle during treatment is often a large part of whether or not a patient accepts a treatment plan. Some considerations for provisionalization include how the provisional will affect a patient’s aesthetic, phonetic, and dietary situations as well as lifestyle with respect to appointment scheduling. As with all treatment planning in implant dentistry, a comprehensive dialogue with the patient is required. It is through this communication process that the clinician will gain a thorough understanding of each patient’s unique needs and desires, and only then be able to customize a provisionalization plan to properly match the situation at hand.
From a clinical standpoint, provisionalization starts with determining if a case is going to be a full-arch case or a quadrant case. The next question is whether or not the case will be an immediately loaded one-stage procedure or a 2-stage procedure. When a case consists of one implant or a quadrant of implants, nonfunctional immediate loading can be done. According to Dr. Carl Misch, nonfunctional immediate loading occurs when implants are placed out of occlusion and function during the 3- to 6-month implant healing period. This will allow a patient to have nonfunctional aesthetic teeth. The presence of either natural teeth or integrated implants is needed for this to happen. The patient will have to be cognitive of avoiding the area that is being nonfunctionally loaded and to chew only soft foods there. Nonfunctional immediate loading is often utilized in the aesthetic zone when a single tooth is being replaced. Various abutments can be used for this, ranging from plastic PEEK abutments (BioHorizons) to titanium-angled or straight stock abutments. Especially in the aesthetic zone, nonfunctional immediate loading offers an excellent way to form the soft tissue around an implant right from the time of surgery. It is obviously important to ensure there is adequate keratinization around the implant at the time of loading, since that is the only planned opportunity to do so. In my practice, I utilize a permanent cement, being sure not to allow any cement into the sulcus. Using a permanent cement avoids the micromovement from a loose provisional crown, which could lead to implant integration issues. If using a permanent cement, the removal of the provisional—when it is time to take impressions—will necessitate the clinician to drill through the provisional and then to unscrew the abutment.
If a single-implant or quadrant case is going to be done as a 2-stage procedure, then the options are as follows: (1) a flipper appliance, (2) Maryland bridge, or (3) bonded tooth (or teeth). If a flipper appliance is being used, then it is important that the appliance be relieved from the tissue surface to avoid interfering with implant integration. In the aesthetic zone, a flipper is not the ideal form of provisionalizing a case, as these appliances do not predictably form an ovate pontic as well as either a bonded tooth or Maryland bridge. While a bonded tooth or Maryland bridge offer stability toward ovate pontic formation and tissue shaping, there are disadvantages. The first disadvantage is the vulnerability of the bonded tooth or Maryland bridge debonding at an inopportune time. For this reason, I usually create a second (backup) flipper. The other issue with these bonded options is that more chair time is needed to rebond the tooth or Maryland bridge.
Full-arch provisionalization has 3 options consisting of (1) a denture, (2) immediately loaded implants, or (3) staging a full-arch case using existing teeth that will be later extracted.
A denture certainly offers simplicity from a full-arch provisionalization standpoint, but some patients are not amenable to wearing a denture. This is the point at which dialogue with a patient becomes important. When a denture is being utilized for full-arch provisionalization, a soft chairside reline of the denture (ie, COE-SOFT [GC America]) is done over the healing caps at uncovery.
Immediate loading of a full arch requires adequate implant stability. In my practice, I immediately load around 90% of the time on the mandible, and about 60% of the time on the maxilla. We use Implant Stability Quotient (ISQ) readings from the Osstell unit (Osstell). When we have a reading of 60 or higher and we are splinting implants, immediate loading is the chosen protocol. Otherwise, we do the case as 2-stage and bury the implants. Immediately loading a full-arch case can substantially reduce the amount of appointments needed for completion of the case. We often complete full-arch screw-retained immediate load cases in 4 total visits. As long as there is adequate implant stability at surgery, the literature shows success rates for immediate loading equal to, or better than, 2-stage with a full arch. When a patient is wearing an acrylic full-arch provisional, the patient’s diet must be soft in nature during the implant integration period. In my practice, I deliver the screw-retained full-arch provisional prosthesis the day after surgery instead of the same day.
After doing this next-day delivery for many years, my team and I have found 4 major advantages. First, by taking an impression at the time of surgery and placing healing caps, there is less chair time and less stress for the doctor and patient. Instead of spending the entire day with the patient delivering a chairside relined provisional, the patient is home at rest and the doctor is seeing other patients. Second, when a laboratory creates a full-arch provisional versus one fabricated at the chair, the provisional is more refined, aesthetic, and stronger than a chairside reline. Third, when this refined provisional is delivered the next day, the tissue at the surgical site has shrunk, there is no bleeding, the delivery is painless for the patient and, in general, the task takes less than an hour for the doctor. The fourth advantage is that the doctor’s schedule is now more controlled. An all-day surgery and delivery can be unpredictable with respect to the time needed. Through a next-day delivery, the appointment times are very predictable and can be scheduled appropriately for the doctor and patient.
The last option for full-arch implant provisionalization, which consists of utilizing existing teeth that will be extracted, can work very well. However, this clinical protocol makes the case more complicated, requires additional appointments, and often makes the provisionalization process more challenging. The option of saving teeth for full-arch provisionalization is better suited for cement-retained full-arch bridges where there is not any alveoloplasty being done. This is what Misch classifies as FP1. When alveoloplasty is needed, saving teeth becomes more of an issue and becomes problematic when timing the different stages of an implant case.
In this month’s Implants Today, we are featuring the work of 2 contributing authors. First, Implants Today editorial board member Dr. Justin Moody’s article entitled “Dental Implant Provisionalization Options” brings to light many of the points that I have made here in this and is backed up by excellent clinical images. Justin also offers even more insights related to this very relevant topic. In “Using an Integrated Digital Approach to Treatment Planning,” Dr. David Little presents an alternative to utilizing flippers for a complicated anterior extraction/implant case. The “snap-on” option allows for much more stability than a traditional flipper, with regard to forming soft tissue and also to avoiding stress on healing implants.
Clearly, as the reader can discern from the information presented here and in this issue’s Implants Today articles, provisionalization of implant cases is vital to the treatment planning protocol. Many considerations need to be taken into account, including how the case will be staged, the number of implants planned, the patient’s desires and lifestyle, and much more. The proper provisionalization plan for each unique case must be made early in the treatment planning process so that the parameters can be conveyed to a patient. The choice of how a case will be provisionalized can even be a factor in whether or not a patient will accept the recommended treatment. Treatment planning implant dental cases involves both surgical and prosthetic decisions.
One last thought about the importance of a provisional restoration is that often the provisional restoration becomes the guide for the final prosthesis with regard to aesthetics, occlusion, and more. Once again, provisionalization is a key component in dental implant treatment that affects the entire case.
It must be kept in mind how surgical decisions directly affect prosthetic results. Examples of this are correct spacing of implants, achieving adequate alevoloplasty for prosthetic thickness, and providing the correct implant angulations; all of these surgical steps directly affect prosthetic success and choices.
This month’s Implants Today topic is “Dental Implants: Prosthetic Options.” This is a very broad topic and yet an important one that relates to all aspects of implant treatment. Although I will be focusing on the many choices of prosthetic options for dental implants, it must be kept in mind how surgical decisions directly affect prosthetic results. Examples of this are correct spacing of implants, achieving adequate alevoloplasty for prosthetic thickness, and providing the correct implant angulations; all of these surgical steps directly affect prosthetic success and choices. Implant dentistry is truly a prosthetic discipline with a surgical base.
The various prosthetic options are also related to treatment planning. In my opinion, treatment planning is about knowing your patient and making a decision with that individual, after he or she is educated on all options in conjunction with a diagnostic exam. The decision of a prosthetic choice with the patient is related to his or her lifestyle, age, and health; the length of treatment; the financial costs; and more. While some patients put aesthetics as a priority, other patients just want to be able to eat without pain or discomfort. It is only through an interview process with the patient that the right decision can be made.
I would like to say a few words about the prosthetic options when treatment planning for both a quadrant of dentistry with one or more implants as well as the full-arch tooth replacement options for a patient.
When you are treatment planning a quadrant of implant-supported prosthetics, there are various options to consider as an implant dentist. The first consideration is whether the crown will be screw- or cement-retained. Screw-retained crowns offer the advantage of predictable retrievability. One consideration of screw-retained prosthetics, especially in the anterior region, is the location of the screw hole. This is directly related to the surgically placed angle of the implant. Another consideration with screw-retained prosthetics is the material of which the crown is being made. PFM crowns tend to have less aesthetic access hole openings than zirconia crowns. Zirconia crowns with a screw access hole also tend to be less susceptible to chipping. When considering screw-retained crowns in the posterior region, the issue of accessibility can sometimes come into play for patients with a limited occlusal opening.
Cement-retained crowns offer the advantage, from an aesthetic standpoint, of not having a screw hole. There is also increased strength of a nonscrew-retained implant crown due to the lack of a screw hole. An issue of concern with cement-retained crowns or bridges is the risk of cement getting into the sulcus, causing peri-implant issues. There are various published methods to avoid this cement issue in the sulcus from happening. Retrievability of cement-retained crowns and bridges can be controlled by the type and amount of cement used, but this is often not predictable. The best way to control retention in cemented implant crowns and bridges is to use custom abutments that have adequate retention and a retentive path of draw. Custom abutments can also allow for corrected angulation when implants are placed in angled root areas. Another consideration, with respect to abutments, is whether to use a zirconia abutment in the aesthetic zone or a titanium abutment. My preference in the anterior region is to use a milled zirconia custom abutment with a titanium base inside for the connection.
When full-arch tooth replacement is being treatment planned for implant-supported prosthetics, there are additional considerations regarding quadrant treatment planning. There are 5 prosthetic options available to restore an entire arch of teeth, each one with advantages and disadvantages; they are as follows: implant-supported overdentures, cement-retained PFM bridges, acrylic hybrid bridges, screw-retained PFM bridges, and screw-retained zirconia bridges.
Implant-supported overdentures offer the most stability when supported by a bar versus being tissue-supported. Overdentures have the advantage of offering more occlusion with fewer implants and less grafting than other fixed options. The disadvantages of overdentures are that they are removable and are less natural-feeling for a patient than fixed alternative options. In addition, since they are acrylic, they will wear down and need replacement in the long term. In general, there are also maintenance issues with overdentures that require replacement of retentive parts. This maintenance of parts requires time and must take into account the associated financial considerations from a practice management standpoint.
From a functional and aesthetic standpoint, cement-retained PFM bridges offer the closest approximation to natural teeth. The same retrievability issues and cement peri-implant issues as with quadrant implant prosthetics exist. If porcelain were to chip, it could be due to the retrievability issues. This choice is one of the most demanding of all the full-arch options, due to the frequent need for extensive grafting and/or sinus grafting. A distal cantilever with a cement-retained bridge is not an ideal situation, because if that cantilever becomes loose, it can be a difficult issue to deal with prosthetically. One advantage of a full-arch cement-retained PFM bridge is that the cement can negate some of the casting distortions inherent in a long-span cast bridge.
Acrylic hybrid bridges are the most problematic prosthetic option of all full-arch choices. The difference between an acrylic overdenture and a hybrid bridge is that the hybrid bridge does not move, thus all the stress is taken up by acrylic teeth that will often chip and break off over time. Acrylic is porous, causing the material to pick up stains, also creating a higher potential for peri-implant issues. Another disadvantage of acrylic hybrid bridges are the screw holes, which are susceptible to chipping. Furthermore, the screw holes are not aesthetic when a composite is placed in them due to the show-through of the underlying metal framework.
Screw-retained PFM bridges can offer an excellent option for full-arch tooth replacement, featuring the advantages of a cement-retained PFM bridge with increased retrievability. Implants Today advisory board member Dr. Jack Piermatti has an exceptional example of this in his article. He clearly explains the prosthetic and dental laboratory steps for success. One key to success with this prosthetic option is to reduce any casting distortion so that stress is not put on the implants.
Screw-retained zirconia bridges have the advantage of being CAD-milled with no casting distortion issues. One reality when treatment planning this zirconia option is that it’s most predictable, from a prosthetic success standpoint, when the zirconia screw-retained bridge has adequate prosthetic thickness. This often mandates that the prosthesis be what Misch calls FP2 or FP3, with a pink gingival area present. This requires either surgical alveoloplasty or natural alveoloplasty from periodontal disease. Another advantage is that zirconia is resistant to chipping when presented without porcelain on the facial aspects of the teeth as a full-contour option. The aesthetics of zirconia allow for a full-contour option in most clinical cases.
While I have spelled out the basic advantages and disadvantages of both quadrant and full-arch prosthetic options, there are many other prosthetic considerations involved to ensure that any of these choices work out successfully. Dental implant prosthetics is a multidisciplinary combination of parts, pieces, and clinical steps that must come together in a coordinated manner.
Much has changed during the past 10 years with respect to SDIs. Years ago, they would have only referred to mini one-piece implants to support an overdenture. Now SDIs include one- and 2-piece implants, offering choices for both removable and fixed prosthetic options.
This month’s Implants Today topic is “Small-Diameter Implants,” or SDIs. Much has changed during the past 10 years with respect to this topic. Years ago, SDIs would have only referred to mini one-piece implants to support an overdenture. Now SDIs include one- and 2-piece implants, offering choices for both removable and fixed prosthetic options. SDIs can be broken up into 2 categories: the mini dental implants (MDIs) that range from 1.8 mm to 2.5 mm in width and 10 mm to 18 mm in length, and the SDIs ranging from 2.5 mm to less than 3.5 mm in width and 12.0 mm to 18.0 mm in length.
The US Food and Drug Administration (FDA) gave 510(k) approval for MDIs, and approval for certain brands can be found on fda.gov. The FDA approval of certain MDI brands is “for use as a self-tapping titanium screw for transitional or intrabony long-term applications.” The MDIs are also indicated, according to the FDA website, for “long-term maxillary and mandibular tissue-supported denture stabilization.”
SDIs also have FDA 510(k) approval. According to the FDA website, the 510(k) clearance for 3.0 mm-diameter-sized implants is stated as the following:
1. An artificial root structure for single-tooth replacement of mandibular central and lateral incisors and maxillary lateral incisors. The SDI may be immediately restored with a temporary prosthesis that is not in functional occlusion.
2. When splinted together as an artificial root structure for multiple-tooth replacement of mandibular incisors. The SDI may be restored after a period of time or placed in immediate function.
3. For denture stabilization using multiple implants in the anterior mandible and maxilla. The SDIs may be restored after a period of time or placed in immediate function.
It is apparent that there are approved indicated uses for dental implants in this size range. These FDA statements are only guidelines for the dental practitioner, and a clinician must make the final decision for his or her patient. Under the appropriate clinical conditions, both MDIs and SDIs have a definitive place in dental implant treatment planning.
When a clinician is formulating a treatment plan to replace missing teeth, spacing of dental implants is a high priority consideration. Implant spacing impacts issues such as number of implants and the proximal bone vascularity. If implants are closer than 2.0 to 3.0 mm, the propensity for bone loss increases, which in turn can create aesthetic issues through soft-tissue loss. Spacing implants too close together can even affect their survival rate. Previously, when the multitude of SDIs was not available, spacing issues were not as easily or adequately resolved by the clinician. Having the option of smaller diameter implants allows for more treatment planning choices as far as spacing issues. The option of different sizes also allows for creativity in treatment planning, with clinicians often combining traditional-sized implants with SDIs.
For the last 5 years or so, SDIs have been available as a 2-piece option. This has completely changed the scope of treatment planning options in a positive manner. There are advantages and disadvantages to one-piece implants. One advantage is the fact that there is not a microgap between the implant and the abutment, which (according to Dr. Carl Misch) allows for a closer proximity between implants and teeth. The disadvantages of one-piece implants, in general, are related to provisionalization and the need for more exact implant placement with respect to angles. If provisionalizing one-piece implants for less than a full-arch case, the implants should be out of occlusion during the healing period. If one-piece implants are used for a full-arch case, then the implants need to be splinted. The angulation of the implant is an issue for every one-piece implant, as angle correction abutments are not available. When a one-piece implant is used to support an overdenture, the patient is committing to the overdenture option. This long-term commitment is one that must be emphasized to the patient.
The surface area of the implant that contacts bone is a consideration of SDIs. With less surface area contacting the bone, the clinician should consider the loading forces on the implants with regard to the patient’s occlusal forces. The patient’s existing height or width of bone also relates to the forces on a dental implant. If there is an increased cantilever due to a lower bone height, this should be taken into consideration. A clinician’s choice to use longer implants, more implants, and implants with increased surface texture are all ways to reduce the forces on implants.
The emergence profile must be considered when treatment planning, especially in the aesthetic zone. If the diameter of an implant is too narrow, then the emergence profile will be too extreme, creating the possibility of hygiene and aesthetic issues. This is especially evident with one-piece dental implants. The multitude of width options from manufacturers and the use of a custom abutment help to negate this issue. It is important for a clinician to be knowledgeable of the manufacturers’ offered options for the various implant systems, as this directly pertains to ideal treatment for a patient. For instance, some manufacturers don’t make multiunit angle-correcting abutments for certain SDIs, which could be an issue for certain implant cases. The ramifications of a manufacturer’s inclusion of parts could also affect issues such as whether digital scans can be taken, if angled abutments are available, or if various healing cap sizes are available for the treatment planned SDI. Gaining in-depth knowledge of a manufacturer’s available parts is an important pretreatment step, especially with SDIs, as there are less parts made for this segment of the market, in general.
In this month’s issue, Implants Today presents 2 excellent articles that discuss the strategies of treatment planning with SDI and MDI options.
Implants Today advisory board member Dr. Steven Cutbirth has contributed a very informative article on using MDIs for full-arch tooth replacement. I especially like this case, as it was done with full reflection and not a flapless technique. This allowed Dr. Cutbirth to do the appropriate alveoloplasty, to see the surgical site, and to place grafting material and membranes. This article shows the utilization of the MDI option to support a denture with an adequate number of implant fixtures.
Dr. Charles Schlesinger has authored an enlightening overview on immediately loading dental implants. This article covers the principles of timing, surface area of an implant, and the appropriate length and width needed for immediate loading. These principles are appropriate for all sizes of dental implants, from MDIs to standard-size implants.
SDIs are another option we can offer our patients. As with every area of implant dentistry, it must be applied with the appropriate knowledge and put in context to both the treatment plan and all other available options. SDIs are holding a strong place in treatment options in implant dentistry.