The specialist society founded in Switzerland in 2018 is comprised of a Europe-wide network of scientifically renowned experts from clinical practice, universities and quality-oriented suppliers in the field of dental and ceramic implantology. In October 2018 the first joint official statement from science and industry was issued, outlining the current status of dental implantology with ceramic implants. Dr. Röhling, was there a specific occasion that marked the statement on two-piece ceramic implants issued some three years later?

Röhling: Essentially, one of the stated aims of the ESCI is to spark up conversations about topics and to develop concepts with which it can support its members in their work with ceramic implants in daily practice. The first official statement from the science and industry that you mentioned is considered a particular success of the first ESCI council, where specialists with a great deal of expertise in ceramic implantology held a round table discussion with representatives of the leading manufacturers. Our ESCI members very specifically looked at two-piece treatment concepts with ceramic implants with an aim to develop an argumentation that can also be used with the private health insurances when it comes to their obligation to reimburse costs.

We already have the scientific data; so now we need to take an evidence-based approach to discuss and address questions that remain open. We have found that treatment with one-piece ceramic implants has been agreed and the costs covered, but that treatment with two-piece ceramic implants is again and again rejected on the grounds that the data are too sparse.

What is the current data status for two-piece zirconia implants? To what extent can the argument brought forward by the insurance companies, that there is not enough data, be disproved?

Röhling: Even though a significant majority of data published to date reference one-piece implant systems from high-performance zirconia, and data on zirconia implants with a two-piece implant design are currently limited, the following is apparent: A meta-analysis performed by our study group into which clinical studies have been integrated has shown that there is no difference in terms of survival rates between one-piece and two-piece implant designs. Even though meta-analyses to estimate the survival rates currently only include 1 to 2 years of data, individual studies report on longer clinical follow-up periods. There are currently clinical data available for commercially available zirconia implants covering follow-up periods of up to five years that show functional loading with 95% survival rates. There are enough data, and we also believe there is enough experience, to be able to recommend two-piece components with zirconia implants. The surfaces have been very thoroughly examined and are the same for one-piece and two-piece implants. So, in other words, one-piece and two-piece zirconia implants have the same degree of osseointegration and biological integrity. Two-piece ceramic implant connections from leading manufacturers have since been scientifically tested and classified as suitable for clinical application, and so it can be concluded that two-piece treatment concepts are just as suitable for practical use, while experts agree that the two-piece zirconia implant concept is suitable for clinical use after properly assessing the indication and explaining the procedure to the patient. What is problematic here, however, is that the industry has different production standards and quality control standards, which then directly affect the reliability of the ceramic implants and prosthetic connection.

The ESCI statement is attached to the relevant literature sites...

Röhling: Correct. The statement provides an objective and independent statement on the data available for the one-piece and two-piece ceramic implants. We want our colleagues to be able to provide scientifically-based arguments and to be able to construct plausible arguments to present to the insurance. Basically, I think it is really important that users look into the products available on the market, to see if there are scientific data available on a specific product. For example, strength and mechanical stability of two-piece zirconia implants may vary depending on the production procedures, material properties, implant geometries and prosthetic connection concepts. Which therapy option and medical device are used is ultimately down to the attending clinician following a discussion with the patient about the available options. There are indications where a two-piece zirconia implant concept will offer a more reliable clinical outcome than a one-piece design.

What are the indications for a two-piece zirconia implant? Do you believe them to be specifically indicated as a reliable treatment option in the esthetic anterior region?

Röhling: I consider two-piece zirconia implants to be a generally reliable treatment option. I do not see them as especially indicated in the anterior region. They have advantages, for example if simultaneous bone augmentation is planned and the implant cannot be inserted with high primary stability. This can be in the anterior region, if a lateral bone augmentation is to be performed. But it could just as well be in the posterior region, if a simultaneous sinus lift is performed, where we build up height and where we want to avoid unexpected overload. Two-piece implants are easier to use in that case, because the abutment does not penetrate into the oral cavity and so unintended premature loading can be avoided.

Two-piece implants are also a reliable option for edentulous patients. Two-piece implants are also superior in that they have greater prosthetic flexibility, as the constructions can be better customized. That can have an advantage if, for example, the prosthetic axis has to be corrected. Also, cement-retention, considered to be prone to errors, is not required if using a two-piece system, as this allows a reversible screw-retained attachment, while in one-piece implants the supraconstruction can only be cemented. This quite clearly expands the range of treatment options provided by the two-piece implant design.

I also see another important consideration to be that many users of titanium implants are more familiar with the clinical handling of two-piece implant designs, and so are more confident using the ceramic implants.

Does this mean that the statement should also encourage new users to introduce ceramic implants into their practice portfolio?

Röhling: We would welcome being able to assuage any skepticism clinicians may have had about two-piece zirconia implants and for them to consider two-piece zirconia implants as a practical and promising concept. That doesn’t mean they should use products blindly and without due consideration. As I mentioned, treatment is at the discretion of the attending clinician who should know what they are working with and who should also explain the treatment to their patients. Essentially, for clinical success, the guidelines of the manufacturer should be observed when using the two-piece zirconia implant system. We want to also reassure users and, with the statement, help them give clear arguments they can use when seeking cost reimbursement from insurance providers, for instance.

How legally robust is this statement in terms of insurance?

Röhling: Guidance issued by a professional society or statements is not legally binding, unlike directives, which are based on a legal foundation. Statements from renowned scientific societies are, however a piece of the mosaic, and are a very important tool that helps to shape contractual recognition of a medical concept. In the current statement, our international independent professional society has compiled the latest evidence-based data and uses this information to comprehensibly and plausibly set out the experts' viewpoint of two-piece treatment concepts with zirconia implants.

We want clinicians to be aware of this information and to use it when deciding on a suitable treatment option and when presenting the case to private health insurances. From our point of view, insurances at least in Germany can no longer shirk their responsibilities when it comes to covering the cost of two-piece ceramic implants.

Of course, many more clinical studies are required to explore two-piece treatment concepts and to show that they are clinically reliable in practice. A task we as physicians and the ESCI as an evidence-based advocacy group face is to continue to translate treatment outcomes into a scientifically validated level of expertise so that there can also be recognition under contract law.

One thing is certain: Ceramic implants are going to continue to gain popularity among patients. In a demographic study conducted in Munich in Germany and Basel in Switzerland, we were able to show that some 40% of patients questioned would opt for a ceramic implant, while only around 10% would go for a titanium implant. We believe that there is a bright future ahead for ceramic implants because they are very good and well-thought-out products.

The ESCI strives to become a strong lobby for ceramic implantology. Which projects are in the pipeline that will help to achieve this goal?

We are currently working hard on the training centers with course and residency options for our members. The training centers are selected and certified by the scientific advisory board of the ESCI, allowing users to get to know zirconia as a material and to develop basic and advanced skills in handling ceramic implants from a scientific and clinical perspective. The uniform professional development concept we have devised is of great benefit: While each course is unique, the aim is to ensure that all participants attain the same standard of expertise after completing the courses at the various centers. The in-person events are supplemented by internet-based professional development, in a “blended learning” concept.

This year we are also focusing on our ESCI annual congress, which we unfortunately had to reschedule in the face of the pandemic. Even though the schedule is not yet fixed, we are in the concrete planning phase: It will be held here in Switzerland, in Horgen near Zürich, from October 21 to 22, 2022 and we hope that it will be an in-person event. The first invitations for our speakers have already been sent out.

Our first European Congress for Ceramic Implant Dentistry held back in October 2019 was already a marked success, with 170 participants from 23 countries traveling to Lake Zürich in Switzerland to find out the “Facts of Ceramic Implants”, as the congress was aptly titled. Even at this first event, the ESCI annual congress was one of the world’s largest and most relevant events on ceramic implantology. We want to build on this success and hope that as a strong community, we will continue to promote the connection between science and practice, as many users are looking for scientifically based and clinically recognized guidance in the field of ceramic implantology.

Many thanks for sharing your thoughts with us,
Dr. Röhling.

Tip: The ESCI statement is available to download here: