Espertise CONTENT EDITORIAL 23 FEB 2013

Transcription

1 Espertise magazine No. 23 FEB 2013 Cmon Fotolia.com EDITORIAL Dear Readers, Similar to edges of a forest, sea, lake or river and field borders which characterize a landscape, margins in the oral environment have a huge impact on the appearance of an individual. A beautiful smile is obtained only if natural soft tissue contours are preserved or restored after implant insertion or restoration placement. Moreover, restoration longevity and a healthy soft tissue strongly correlate with the quality of the restoration margin. In order to support you in obtaining perfect margins, 3M ESPE offers a whole variety of innovative products, which will all be presented in Cologne at the world s largest dental trade fair and meeting place of the dental industry: the IDS. This is the place to be for all those who want to be informed about the latest trends and approaches in dentistry. You are invited to visit the IDS booth of 3M ESPE to obtain first-hand information about new materials and devices e.g. from the product developers and pilot users. On the spot, you may test the innovations and compare them to each other. Additional insights are given in this issue of the Espertise Magazine. It is composed of articles written by researchers, clinicians and developers who love to share their personal perspectives and clinical experience with you. Enjoy reading! Gerhard Kultermann, Editor 3M ESPE, Seefeld, Germany CONTENT It s all about the margin...2 Improved marginal accuracy through standardization...3 Quality is an integral part of 3M ESPE!...4 Direct restorations: lifelike appearance, perfect margins...6 New generation cement with efficient marginal adaptation...8 Faster, easier and more convenient!...9 The effect of different retraction techniques on the gingiva...10 Practise-based research results on handling properties The impact of soft tissue management on marginal quality of restorations...12 Optimized features for even higher accuracy...14 How digital technologies may contribute to marginal quality...16 A conservative approach to indirect restorations...18 Dentistry in the Kingdom of Belgium Dentistry in Israel The solution for compromised patients... 22

2 Scientific Activities Espertise Experts Roundtable 2012 It s all about the margin Frédéric van Vliet, 3M ESPE, Seefeld, Germany 2 In restorative dentistry, there are different kinds of margins which have a decisive impact on the aesthetics and functioning of the final result, including the finishing line of the preparation, the edge of the restoration and the gingival margin. Event location at Lake Starnberg in Germany. The preparation and its finishing line have to comply with certain preparation guidelines in order to ensure that a precisely fitting restoration can be produced and placed that remains stable over time. At the edge of the restoration, precision and smoothness are of utmost importance: Irregularities at this margin may result in an improper fit and may lead to tissue inflammation, bone resorption and ultimately to failure of the restoration. Apart from accuracy, a tight seal of the interface between the tooth and the restoration must be obtained, no matter whether direct or indirect restorations are placed. Only with a strong bond is it possible to prevent the occurrence of discolouration, microleakage, secondary caries and post-operative sensitivities. The gingival margin influences pink and white aesthetics, which is strongly dependent on perfect tissue management. These and additional topics around the margin were addressed by renowned speakers and an exclusive group of dental professionals which were invited by 3M ESPE to attend an Espertise Experts Roundtable at Lake Starnberg near Munich, Germany in November Here, e.g. Various topics were discussed during the lecture programme and in the breaks.... about recently conducted studies and their outcomes. different approaches towards an improved quality of the restoration margin and techniques for soft tissue management were presented from both, a clinical and a scientific viewpoint. After two days of lectures, poster presentations and discussions with colleagues, the participants agreed that the margin influences restorative dentistry in many ways. It was concluded that a high quality of the final result can only be ensured through exact planning of a treatment, the use of advanced materials and devices and a standardization of workflows in practice and laboratory. Renowned speakers reported on their clinical experience and research findings. During the poster presentations, young researchers provided information... Exchange of ideas and opinions. No. 23 FEB 2013

3 Ask the Expert Espertise magazine Restorative dentistry Improved marginal accuracy through standardization Bernd Wöstmann, Giessen, Germany The striving for a perfect margin in restorative dentistry is a well-known phenomenon: scien- Original dimension of the tooth immediately after tooth preparation if the area can be dried successfully. If this is not possible, a 3 tific-based knowledge indicates that inflam- Impression latency of approximately ten days is recommended mation of gingival tissues and bone destruc- to ensure complete healing of the soft tissue. The tion correlate directly with a poor quality of the restoration margin. However, in the production process of an indirect restoration, there are many different factors that may lead to marginal inaccuracies. Strategies to avoid the occurrence of these imperfections are dis- smaller a) d) b) e) c) larger Cast production impression technique may be selected depending on the indication and individual preferences. Standardization of processes What should also be taken into account is that the cussed in the following article. Original dimension of the tooth altering of process steps, materials and production conditions in the treatment workflow may lead to Factors influencing accuracy Impression differences in the accuracy of the final result. For example, using more than one impression material The first sources of inaccuracies evolve from tooth or different types of plaster for cast production in the preparation which, in clinical reality, often does not smaller larger restorative processes makes the result less predict- meet all criteria with regard to the perfect finishing able, since e.g. the polymerization shrinkage or line. Irregularities in the margin and a restoration Cast production expansion factors are different. Only the use of the placed closer than 3 mm to the alveolar crest, for same materials and the same work steps in every example, foster tissue inflammation. According to in-vitro and clinical studies, the margin design is d) e) process reduces the variability of the results. This standardization should be carried out in the dental also important for accurate restorations. A chamfer Original dimension of the tooth practice and laboratory and even should involve design seems to lead to the best results. equal production conditions. For example, a uniform Impression temperature in the plaster room to always induce In addition, inaccuracies are created in the pro- the same material expansion is very important. cess of transferring information from the patient s mouth into the dental laboratory. Errors resulting from one step in the treatment and laboratory workflow are usually not compensated by another smaller larger Cast production Conclusion The aim of modern restorative dentistry is the crea- but persist through the whole process and may tion of long-lasting restorations which perform like even add up to a greater error. d) e) the natural teeth they replace. For a reliable perfor- The impression The impression taking process is particularly chal- Effects of inaccuracies in the fabrication process of a crown. In a first approximation, the size distribution of the represented crown lumina in an impression may be regarded as the normal distribution (above). The same applies to the master cast (below). (e) represents the acceptable range for the crown lumen. mance, accuracy of a restoration and marginal quality play a decisive role. In order to create restorations with perfect margins, not only high-quality dental biomaterials and techniques are needed. A well- lenging due to the moist oral environment and anaesthesia reduces the risk for failure by a factor structured management of the patient, the tissues potential bleeding of the sulcus. Studies have of five. In order to lay the foundation for an accu- and the biomaterials used is highly important as well. revealed that taking the impression under local rate impression, the process should be carried out

4 Ask the Expert Looking behind the scenes... Quality is an integral part of 3M ESPE! Frédéric van Vliet, 3M ESPE, Seefeld, Germany 4 Quality means doing it right when no one is looking, says a quote attributed to the American industrialist Henry Ford, the founder of Ford Motor Company. Indeed, the quality of a product is defined by people and processes Dr. Viehbeck, in Research & Development of dental materials, Quality Management is of major importance. Why is quality so crucial for 3M ESPE? are launched, perform the way they are intended to perform. Please describe the different stages of product development from the initial idea to that are usually invisible to the common user. In the company s laboratory, developers collect ideas, translate customer wishes into technological specifications and combine various technologies and ingredients to obtain a new material or device. The quality of the final product is determined by how every step in this process is performed and monitored. The confidence our dental professional customers have in us is at stake every single time they use one of our products. Because of that we are committed to the highest standards in everything we do. Our customers know that they can count on our products to work right the first time, and the same way time after time. product introduction. We use a process for new product development which includes Ideation, Concept, Feasibility, Development/Scale-up, and Launch phases. Essentially, new ideas are taken through a maturation process, where questions of technical viability, market viability, manufacturing, commer- In order to learn more about these invisible processes and the internal measures that are implemented at 3M ESPE to ensure an excellent product performance, we had a conversation with Dr. Alfred Viehbeck, Vice President, R&D Materials of the 3M ESPE Dental Products Division. As the head of the global R&D laboratory with locations In order to ensure that the highest quality standards are met, we have a separate Quality Management Department that includes Regulatory Affairs, Product Safety and Quality Assurance. However, Quality Management touches every individual employed at 3M ESPE. Quality Assurance, for example, is an integral part of our New cialization, and of course product quality are addressed. We have a highly disciplined gate review process involving the leaders from each function in order to ensure that all key questions and concerns are appropriately addressed before allowing the program to proceed. As part of our efforts to make sure we get things right, we are not afraid to stop, or delay, a program before in St. Paul, Minnesota and in Seefeld, Ger- allowing the team to proceed. many he has responsibility for the material and technological innovations that are cre- Please give a few exam- ated within the company and is able to pro- ples of what kinds of vide insight into the role of quality at quality assurance tests 3M ESPE. are performed during the different phases. To gain the true voice of the market and the voice of the customer we do surveys, inter- Left: St. Paul, USA. Top: Seefeld, Germany views, focus groups, application tests, and field evaluations throughout the Product Introduction process. product development cycle. During actual product It is of significant importance development, numerous tests are performed. In in making sure new products, vitro testing is usually done in our certified ISO from the very moment they approved laboratory. For a material like 3M ESPE No. 23 FEB 2013

5 Espertise magazine Employee working in the research laboratory And there is evidence that this strategy leads to success: data from independent third-party surveys we conduct suggests overall satisfaction with 3M ESPE is the highest among the dental manufacturing companies we survey. This is how we are rewarded for our efforts. What are your plans for the future? We will continue to develop products that benefit the dental industry, oral care providers, and patients with faster, easier, and better dentistry. For the eighth consecutive year, 3M ESPE was named the most innovative dental company in the industry by the Anaheim Group in its independent evaluation published in the Dental Industry Review 5 of 3M ESPE in Seefeld, Germany. RelyX Ultimate Adhesive Resin Cement, e.g. extraction tests to assess product safety, mechanical property and adhesion tests to evaluate product performance are conducted. In addition, the process includes shelf life tests and accelerated aging to determine the strength, durability and reliability of the product. Stain testing serves as a means of checking the product s resistance to discolouration, a factor that is important for long-lasting aesthetics. After launch, the product performance is continuously monitored. In addition many thirdparty in vivo clinical studies are commissioned to substantiate all product claims. Determination of the 3-point bending strength of a zirconia specimen with a Zwick universal testing machine. Is it this reward that makes you like your job at 3M ESPE? There are different factors that make my job satisfying. For me, the close interactions with customers are the most enjoyable. Another aspect is that we are part of the bigger 3M Company and have access to technologies and expertise across our many businesses and the 3M Corporate Research Laboratory. Making a difference in the lives of our customers and having satisfied patients due to our products is also highly rewarding. Dr. Alfred Viehbeck 2012, and hopefully our future new products will sustain this legacy. My mission will be to ensure that this laboratory delivers the highest quality products, invests in technology development for differentiation, and has the most highly motivated, dedicated workforce. Dr. Viehbeck, thank you for providing insights into internal processes at 3M ESPE.

6 Clinical Excellence 3M ESPE Filtek Supreme XTE Universal Restorative Direct restorations: lifelike appearance, perfect margins Hein de Kloet, Arnhem, the Netherlands 6 Figure 1: A 37-year-old male patient with severely eroded teeth presenting in the dental practice. The maxillary anterior teeth are only just visible when the patient is smiling. The cause of the erosion remains unclear even after anamnesis. Figure 2: The existing restorations are insufficient due to discolouration and microleakage. After a presentation of possible treatment outcomes on the basis of digital imaging, the decision is reached to restore the maxillary anterior teeth with 3M ESPE Filtek Supreme XTE Universal Restorative. Figure 3: From an occlusal view, the discolouration is particularly intensive. The erosion is most severe at the lingual and incisal areas of the central incisors. Figure 4: Situation after removal of a large part of the old fillings. Tooth structure at the lingual surface has to be removed as well to create sufficient space for composite material. Wherever possible, an equigingival preparation margin is designed in order to protect the soft tissue. Figure 5: A metal band is used for build-up of the lateral incisors with 3M ESPE Filtek Supreme XTE Universal Restorative in the shade A2B. The bonding procedure is performed using the etch & rinse technique with etchant and 3M ESPE Scotchbond Universal Adhesive. Due to low caries activity, the initial caries at the central incisors is not treated. Figure 6: The lingual areas of the two central incisors are built up in the same manner employing an etch & rinse bonding procedure. The same composite material in the shade A2B is applied. Then, the occlusion and articulation are checked. No. 23 FEB 2013

7 Espertise magazine 7 Figure 7: Buccal view of the situation. The lingual build-up in this primary stage is performed to enable the placement of rubber dam for further direct restorative procedures. Figure 8: Rubber dam is placed and the prepared teeth are sandblasted to ensure a proper adhesion to the residues of old composite material. After the adhesive procedure, the core restorations are created using 3M ESPE Filtek Supreme XTE Universal Restorative in the shades A3B on the canines and A2B on the incisors. Figure 9: Directa Matrix Strips (Directa) are utilized for good marginal adaptation of the filling material. In this stage, the correct definition of the midline is particularly important. During build-up of the approximal contours, care should be taken not to have too much excess material in the cervical area. Figure 10: After removal of the excess material the planned shape of the new restorations is already visible. Figure 11: The occlusion is checked and a small amount of grey colour liquid (Kolor + Plus, Kerr) added before the composite facings are created. For isolation of the cervical part of the teeth, AutoMatrix metal bands (Dentsply) are used. Subsequently, the adhesive procedure is performed again. Figure 12: With the metal band in place, the canines are restored with composite material of the shade A3.5B in the cervical and A3B in the incisal area. A3B and A2B are used on the lateral incisors and on the central incisors a layer in the shade A2B is applied. A natural appearance of the incisal edge is obtained by the use of white colour liquid imitating white spots and small enamel cracks. Figure 13: Situation after finishing of the vestibular areas using a flame shaped diamond bur and a fine diamond instrument. For polishing, 3M ESPE Sof-Lex Contouring and Polishing Discs and a buffing wheel are employed. Relatively deep bite conditions are visible, but these are perceived as comfortable by the patient. Figure 14: Several months after the treatment: a natural surface structure including grooves and a subtle translucency in the cutting edge are obtained. Together with the imitated micro cracks and white spots and a smooth transition between the restorations and the soft tissue, this ensures a lifelike appearance of the restorations.

8 News and Innovations 3M ESPE Ketac Cem Plus Resin Modified Glass Ionomer Cement New generation cement with efficient marginal adaptation Eva-Maria Popp, 3M ESPE, Seefeld, Germany 8 Since January 2013, a new generation of 3M ESPE Ketac Cem Plus Resin Modified ated. Scanning electron microscopy and a dye penetration test were used to assess marginal seal Glass Ionomer Cement is available. The fluo- perfection before and after thermocycling and ride-releasing luting material is indicated for mechanical loading (TCML). the cementation of metal and PFM crowns, bridges, inlays and onlays as well as oxideceramic restorations, endodontic posts and orthodontic appliances. In addition, it can be used for luting of restorations to implant Tack-curing of 3M ESPE Ketac Cem Plus Resin Modified Glass Ionomer Cement. This procedure facilitates the removal of excess cement. Results Ketac Cem Plus revealed 100% perfect margins to dentin before and after TCML when the tack-cure abutments. Dentists can choose between two different delivery systems an automix Efficient marginal seal feature was used for excess removal [1]. The marginal integrity of Ketac Cem Plus to dentin and enamel syringe and the Clicker Dispenser. The efficient marginal seal to enamel and dentin of before and after TCML was closer to perfect than for Ketac Cem Plus after tack-curing could be con- other resin-modified glass-ionomer cements [1, 2]. firmed in an in-vitro study at the University of Regensburg, Germany [1]. In order to assess the With the new tack-cure clean-up feature that now quality of the margin, ceramic inlays were cemented offers easy excess cement removal, Ketac Cem on human molars using different materials. Plus cement provides efficient marginal seal to After application of each cement according to each dentin and enamel. 3M ESPE Ketac Cem Plus Resin Modified Glass Ionomer Cement is available in the Clicker Dispenser and in an automix syringe. manufacturer s recommendations, e.g. tack-curing of Ketac Cem Plus, as well as subsequent removal of excess cement, the interface between the restoration and enamel respectively dentin was evalu- [1] Sawaljanow A, Lang R, Handel G, Behr, M, Rosentritt M. Invitro Marginal Adaptation of Resin-Modified Glass Ionomer Cements to dentin and enamel. Abstract #170549, IADR [2] Partially cited from: Rosentritt M, Behr M, Lang R, Handel G. Influence of cement type on the marginal adaptation of all-ceramic MOD inlays. Dent Mater Jun; 20(5): Tack-cure clean-up feature Dentin Enamel Based on the clinically proven formulation of its predecessor, the new generation cement was optimized not only to offer an easier application with the automix option: the major improvement is the new tack-cure feature that allows for easy excess cement removal after application of Ketac Cem Plus cement and placement of the restoration. By light-curing each restoration surface for five seconds, the excess cement reaches the gel state and can easily be removed in large sections from the margins. Alternatively, the user can wait two minutes after seating for the excess to selfcure. Median Perfect Margin (%) , ,3 90,2 87,3 Before TCML After TCML Before TCML After TCML Before TCML After TCML 3M ESPE Ketac Cem Plus Automix [1] no conditioner GC Fuji CEM Automix [1] no conditioner 92,8 86, GC Fuji PLUS Powder/Liquid with GC Fuji Plus Conditioner [2] Schematic representation of the study results (source: A. Sawaljanow, R. Lang, G. Handel, M. Behr, M. Rosentritt [1] ). No. 23 FEB 2013

9 Backstage Report Espertise magazine 3M ESPE Astringent Retraction Paste Faster, easier and more convenient! Andreas Maurer, 3M ESPE, Seefeld, Germany As a company with a long tradition in the development of products for impression tak- sule had to be developed that enabled placement of the paste directly into the sulcus without dam- very small. Since the transmission of the dispenser could not be altered, the task had to be 9 ing, 3M ESPE knows that it is not the impres- aging the tissue. A very small tip and an ergo- accomplished by optimizing the selection and sion material alone that ensures a precise nomic capsule design were the solution. In order ratio of fillers. The compatibility of the new paste result. An important precondition for an to achieve best possible astringent properties dif- with impression materials and its suitability for the accurate reproduction of marginal details is ferent paste formulations were developed, tested digital impression taking process were verified by the retraction of the gingiva and an open, dry and compared. The one with outstanding astrin- extensive testing. sulcus. Having identified the need for an gent effect was finally chosen containing alumin- easy-to-use paste for gingival deflection, 3M ESPE decided to initiate a development ium chloride and other coagulation accelerators. Product quality project in Since there are no existing ISO norms for testing retraction pastes, the team developed different Development goals analytical measurement systems and procedures to obtain detailed information about the product s Formulating the goals of the project, it became performance. For example, data was collected on clear that its realization would be anything but the time required for removal of the material, the easy: many different features were regarded as important in order to enhance the process of soft Dr. Anrdreas Maurer, Research Chemist at 3M ESPE, Seefeld. ability of opening the sulcus and the flow resistance. The results were also compared to those tissue retraction. achieved with other pastes and in the last step The task of developing a paste that is dispensed prior to product launch, a field test was initiated The basic goal was to invent a product that offers without the need of a new device was particularly worldwide. Here, 80% of the respondents stated mechanical retraction and enables control of exu- challenging. The idea was to enable application that 3M ESPE Astringent Retraction Paste was dation during impression taking as well as cemen- with a common composite dispenser that is avail- easier to use than the paste they usually utilized in tation. The development team was also in agree- able in every dental practice. The problem: the their dental office. Together, the test results con- ment about needing a material that is suited for paste has to be stiff to remain in the sulcus, albeit firmed that the new paste is indeed faster, easier digital and conventional impression taking. A a low extrusion force is essential for precise and more convenient than other available prod- decisive factor for user convenience was the intraoral application and the tip of the capsule is ucts. development of a material that could be applied without the necessity of purchasing an additional dispenser. Last but not least, the innovation should be faster, easier and more convenient for both, dentist and patient, than any existing product available on the market. A tough nut to crack 3M ESPE Astringent Retraction Paste is the only stiff retraction paste that can be applied with a common composite dispenser. Having defined these goals, the team set to work. In order to achieve mechanical retraction, a cap-

10 Ask the Expert Soft tissue management The effect of different retraction techniques on the gingiva Ralph G. Luthardt, Ulm, Germany 10 Soft tissue management is an important procedure to allow for exact capture of the preparation margin during impression taking. Diverse techniques and materials are available to induce the effect of gingival retraction, ranging from retraction cords to the use of lasers. In many dental practices, impregnated retraction cords are applied in the double-cord technique to obtain the desired effect. However, this method is highly complex as well as time-consuming, so that alternative techniques and materials are developed and tested. Study design In order to measure the gingival displacement capacity of the paste versus two cords under healthy soft tissue conditions and with mild artificial gingivitis, a split-mouth study design was adopted. An impression was taken and a saw model produced after application of either two retraction cords (double-cord technique) or the paste containing aluminium-chloride on the maxillary premolars of one quadrant. The other maxillary quadrant served as control. The intervention was the same at baseline under healthy soft tissue conditions and after six months, when the quadrant was changed and mild artificial gingivitis was induced by refraining from tooth brushing. Impressions were taken prior to and after each intervention as well as after three and six months. For three-dimensional analysis of the produced models, the casts were digitized with a laboratory scanner and the amount of vertical displacement of the soft tissue measured and analyzed using specific software. Prof. Dr. Ralph G. Luthardt, University of Ulm, Germany. Against the background of the development of an astringent retraction paste, the company 3M ESPE sponsored research of the Department of Prosthetic Dentistry at Ulm University (Germany). The aim of the project was to assess and compare the effect of an existing paste containing aluminium-chloride with that achieved with impregnated retraction cords used in the doub le-cord technique on the gingiva. This comparison should help to find out if a paste is a suitable alternative to cords in the clinical environment. The benefit of using a paste is the ease of use of the product and a less time-consuming procedure. Results and conclusions It was found that neither the application of the paste nor the use of cords for soft tissue management did lead to permanent recession of the gingiva. Mild artificial gingivitis did not have a negative effect on retraction when the paste was used. A deeper penetration of the impression material was achieved with the cords (source: webprogram/paper html). Additional study results will be published at the IADR/AADR/CADR General Session in Seattle on March 20 to 23, The available information, however, indicates that retraction pastes may be a suitable alternative to cords in many situations. The new 3M ESPE Astringent Retraction Paste might even be capable of achieving a greater depth of penetration since it is applied into instead of on the sulcus. No. 23 FEB 2013

11 Ask the Expert Espertise magazine 3M ESPE Astringent Retraction Paste Practise-based research results on handling properties Trevor Burke, Birmingham, United Kingdom Scientific studies whether in vitro or in vivo are conducted to provide evidence of a product s suitability for a defined purpose. However, even clinical studies are usually carried out under idealized conditions so that the results are not always applicable to the common dental practice. Therefore, practisebased research is highly important. The term indicates that general dental practitioners conduct clinical research in the busy practice environment. They evaluate products in respect of their handling or their long-term clinical performance. This kind of assessment by independent practitioners reflects real life and thus helps dentists to find a material or device that suits their needs. On the basis of this idea, the PREP panel (Product Research and Evaluation by Practitioners) was founded by five colleagues and me in Birmingham in By now, the group consists of 33 experienced dental practitioners mainly based in the United Kingdom who test and evaluate new materials and devices in their own dental office. In the past years, numerous reports have been published by the group and provide a useful source of information for colleagues. Recently, the new 3M ESPE Astringent Retraction Paste was tested and evaluated by members of the panel. Handling properties in focus Since existing gingival retraction techniques e.g. using cords, kaolin or aluminium chloride and astringent solutions have not gained total acceptance so far, the introduction of a new solution in this field was generally appreciated by the members of the PREP panel. In order to obtain information about the handling properties of the new product, a study was initiated and the paste tested by twelve evaluators. They were asked to use the new retraction capsules for ten weeks in their dental practice environment and complete a questionnaire afterwards. Easy-to-use product During the ten weeks of testing, the new paste was used for more than 150 impressions and Prof. Dr. Trevor Burke, University of Birmingham, United Kingdom. several restorations. The questionnaire included information on what kind of gingival retraction system was usually employed so that the performance of the previously preferred product and the new paste could be compared. Other questions focused e.g. on dispensing, the suitability of the paste for gingival retraction, capsule design and the efficiency of the whole retraction procedure. 11 The 3M ESPE Astringent Retraction Paste obtained good scores across all criteria. In comparison with the retraction system that was originally used by the evaluators, the new paste in the innovative capsule received high ratings with regard to its ease of use. The detailed scientific results of the study will be published in the very near future. The new retraction paste comes in a single-use capsule.

12 Clinical Excellence 3M ESPE Astringent Retraction Paste The impact of soft tissue management on marginal quality of restorations Rafał M dzin, Gryfino, Poland 12 Soft tissue management has a huge impact on the marginal quality of indirect restorations. The gingiva has to be deflected in such a way that a detailed record of the preparation margin can be captured with the impression material or the intraoral scanner if a digital procedure is chosen. Traditionally, soft tissue retraction is achieved with retraction cords. They are available in different designs and some of them are impregnated with haemostatic agents. Retraction paste systems and surgical methods such as laser tissue sculpting or electro-surgery have been adopted more recently. Figure 1: Initial situation: the maxillary left central incisor of the young female patient is restored with an insufficient porcelain-fused-to-metal restoration Figure 5: A provisional is produced using 3M ESPE Protemp 4 Temporization Material and fixed with 3M ESPE RelyX Temp NE Temporary Cement. The new 3M ESPE Astringent Retraction Paste for gingival deflection and haemostasis presents a suitable alternative to the existing cords in many cases. It is applied directly into the sulcus to open it mechanically and to stop exudation. Depending on the depth of the preparation and the level of sulcular exudate flow, it may eliminate the need for a cord completely or may replace the second retraction cord when the double cord technique is indicated. The innovative product proves its worth especially in situations with a minimally invasive preparation. The benefits of its use are a quicker and more comfortable procedure as compared to the traditional workflow. Figure 2: the right lateral incisor and canine previously received endodontic treatment and show discolouration. The right central and left lateral incisors are slightly discoloured as well. Figure 3: After removal of the crown on the left central incisor, a heavily discoloured abutment tooth restored with a metal post is revealed. Figure 6: The temporary crown helps the patient to assess the appearance of the planned restoration. Beyond that, it is used to support proper healing of the soft tissue. Figure 7: Tooth preparation: the left central incisor and right canine are prepared for all-ceramic crowns, while a minimally invasive preparation is carried out on the other maxillary incisors, where porcelain adhesive restorations are planned. In the following article, a patient case is presented to illustrate the combined use of retraction cords and the innovative astringent retraction paste that has been introduced by 3M ESPE. Figure 4: Whenever possible, a restoration margin should be placed on an equigingival level. Due to severe discolouration, however, a subgingival preparation is required on this tooth. The stump with the old post is prepared, sandblasted, treated with 3M ESPE Scotchbond Universal Adhesive and covered with a composite opaquer. Figure 8: The double-cord technique is indicated for the teeth with crown preparations due to the subgingival margin and severe exudation. The non-invasive retraction method using 3M ESPE Astringent Retraction Paste is chosen for the right central incisor and both lateral incisors. No. 23 FEB 2013

13 Espertise magazine 13 Figure 12: Retraction effect on all prepared teeth. At the teeth with crown preparations, one cord is removed while the other one is still in place. Figure 16: Final restorations in place, immediately after cementation with 3M ESPE RelyX Ultimate Adhesive Resin Cement in combination with 3M ESPE Scotchbond Universal Adhesive. Figure 9: Close-up view of the minimally invasive preparations on the right central and lateral incisors before Figure 13: An impression is taken in the monophase technique using 3M ESPE Impregum Penta Soft Polyether Impression Material. All details of the finishing line are perfectly visible in the impression. Figure 17: Thanks to the accurate record of marginal detail obtained by soft tissue management prior to impression taking, the fit of the crowns and veneers is excellent. Highly aesthetic restorations are obtained which are indistinguishable from natural teeth. Figure 10: and after the use of 3M ESPE Astringent Retraction Paste. The paste was removed after 2 minutes by rinsing with water. Figure 14: The effect of the preparation and the efficient gingival retraction are visible on the plaster model: the finishing lines were precisely transferred to this replica of the situation in the patient s mouth. Figure 18: This is partly due to perfect margins: the soft tissue is healthy and has a natural shape. The patient is very happy with the beautiful treatment result. Figure 11: The retraction effect is clearly visible: the preparation margins are exposed on both teeth since the tissue is displaced. Furthermore, an open, dry and clean sulcus is obtained. There is a visible change in distance between the soft tissue and the preparation margin. Figure 15: The final restorations: three glass ceramic veneers and two crowns fabricated using the refractory die technique after etching of the inner surface with hydrofluoric acid and application of 3M ESPE Scotchbond Universal Adhesive. Dr Rafał M dzin Dentura Clinic & Lab Poland gabinet@dentura.pl

14 Ask the Expert 3M ESPE Imprint 4 VPS Impression Material Optimized features for even higher accuracy Julia Farr, 3M ESPE, Seefeld, Germany 14 On the occasion of the International Dental Show in Cologne in 2013, an innovation in nents would have to be added or changed to reach our goals. We decided to alter the colours impression taking is presented by a leading for enhanced readability of the impressions and company in this field, 3M ESPE. The new add flavour for an improved patient experience. 3M ESPE Imprint 4 VPS Impression But the optimization of hydrophilicity and the set- Material stands out due to optimized features ting behaviour were in the centre of attention. Dif- and attracts the dentist s attention with its ferent approaches on how to proceed were dis- bright colours. Insights into material development and an overview of the benefits of Impressions with the new materials: 3M ESPE Imprint 4 Penta Heavy with Imprint 4 Regular cussed and the team of researchers developed the basic technologies, one to enhance hydrophi- Imprint 4 are given by Dr. Peter Osswald, licity and the other improving the setting behav- Research & Development Impression Materi- iour. als at 3M ESPE. How did you proceed in order to change the Dr. Osswald, addition silicone impression setting behaviour? materials are available since the 1970 and have been subject to continuous improve- What was difficult was not to just shorten the ments ever since their introduction. After such a long time, it might be assumed that 3M ESPE Imprint 4 Penta Putty with Imprint 4 Super Quick Light whole setting regime, but to reduce time required for the setting reaction in the patient s mouth, a material with the optimum composition is while the working time had to remain the same. already available. So for what reason did After an intensive ideation process and testing of you decide to initiate another product different approaches, we reached the goal by development project for a VPS impression adding a self-warming mechanism to the existing material? formula of VPS materials. I believe that there always is and will be room for improvement of any material. The perfect composition does not exist, partly because trends and and 3M ESPE Imprint 4 Penta Super Quick Heavy with Imprint 4 Super Quick Light. user preferences change over time and technological progress never stops. In order to deliver products that are tailored to ideally suit the needs What were the first steps of product development? Ordinary VPS impression material Imprint 4 Impression Material of our customers, we are always collaborating with users and do never stop analyzing which features might be worth altering. For VPS materials, We did not have to start from scratch, but were able to build on existing knowledge and experi- The rise in temperature of 3M ESPE Imprint 4 is clearly visible with the thermographic camera. we found that a different setting behaviour with ence from developing vinyl polysiloxane impres- The reaction that initiates warming starts after the faster intra-oral setting but identical working sion materials. Furthermore, we have within 3M working time and the rise in temperature leads to times as existing VPS materials from 3M ESPE the unique ability to get access to a large variety accelerated setting. This property results in a would be beneficial. In addition, an even higher of different technologies. We focused on the exist- more efficient workflow, increased patient com- hydrophilicity is desired by dentists. ing composition and determined which compo- fort and less stress for the practice team. No. 23 FEB 2013

15 Espertise magazine Product TRAY MATERIALS Dispensing system Viscosity Setting version Working time (23 C) Intra-oral syringing time (37 C) Intra-oral setting time (37 C) Imprint 4 Penta Putty Putty Regular Set 1:30 2:30 Imprint 4 Penta Heavy Heavy Body Regular Set 2:00 2:00 Imprint 4 Penta Super Quick Heavy Heavy Body Fast Set 1:15 1:15 WASH MATERIALS low high Due to the highly motivated team and Imprint 4 Light Regular Set 2:00 1:00 2:00 with all individuals acting in concert, we succeeded in developing not one, Imprint 4 Super Quick Light Fast Set 1:15 0:35 1:15 but ten new impression materials with Imprint 4 Regular Regular Set 2:00 1:00 2:00 highly beneficial features. Due to Imprint 4 Super Quick Regular Fast Set 1:15 0:35 1:15 higher hydrophilicity and a faster setting in the mouth, an accurate reproduction Overview of the product portfolio of 3M ESPE Imprint 4 VPS Impression Materials. of details is possible. The results of an application test in Western Europe and the United How was it possible to develop a VPS impression material that is even more hydrophilic than existing materials? So, you succeeded in developing two new basic technologies. Was it difficult to combine them with each other and the other components? States confirmed the high level of user satisfaction which makes us very confident that we have addressed the right issues for our customers: for example, the intra-oral setting time received high We know that hydrophilicity is one of the most important properties of an impression material: the more hydrophilic it is, the better is its potential for precise detail reproduction in a wet environment. Detailed impressions, in turn, lead to restorations with accurate margins. Therefore, we spent a lot of time focusing on The two basic technologies were just merged and it turned out that they did not have a negative effect on each other or the whole composition. However, it was more challenging to work out all the different variants of the impression material. A whole portfolio of Imprint 4 products was developed, consisting of materials in ratings. Furthermore, 80% of the respondents in Western Europe and 88% of the US-respondents stated that they will or will probably use the new materials in their own dental office. Dr. Osswald, thank you for the conversation. this topic. Many different technologies and with different additives were tested, but the addition of the viscosities and 70 novel modified polyalkylene oxide wetting enabler setting times in 60 % 50 turned out to be the best solution. This order to satisfy 40 component in combination with our long-term all customers proven surfactant leads to an outstanding preferences 10 0 hydrophilicity of the material even in the and requirements. Much too long Somewhat too long Just Perfect Somewhat too short Much too short uncured state immediately after mixing, so right Exten- Dentist s ratings for intra-oral setting time of 3M ESPE Imprint 4 Tray Materials. Source: Field evaluation from the start. sive develop- EU and US conducted by 3M ESPE and Key Group Research (total sample size: 300). ment and laboratory testing under involvement of a lot of different functions within our company was required to prove the outstanding performance of all materials. What is your conclusion regarding the success of the project? 15 Imprint 4 Super Quick Ultra-Light Fast Set 1:15 0:35 1:15

16 Ask the Expert Digital Dentistry How digital technologies may contribute to marginal quality Albert J. Feilzer, Amsterdam, the Netherlands 16 Many different digital technologies are used in dentistry today: practice management soft- Impression. Since then, diverse companies have focused on the development of devices that are essential to train dentists and dental technicians in how to use the new hardware and software prop- ware runs on every computer, digital radio- capable of capturing precise three-dimensional erly. This starts with basic dental education e.g. at graphs are taken, implant positions are planned data in the oral cavity. Several years ago, they university or a vocational school. However, it has to in computer-aided procedures and CAD/CAM finally succeeded in introducing practicable solu- be taken into account that it takes most students of processes are employed for the production of tions that met the requirements regarding the dentistry about five or six years before they begin dental restorations. The idea behind the intro- precision of the procedure and its suitability for practicing the profession. Thus, universities should duction of digital technologies is that conveni- the production of multi-unit restorations. not only teach digital techniques: they should even ence and efficiency of processes is increased be ahead of dental practices, implement technolo- and highly accurate results are obtained. When comparing the workflows of conventional gies before they are available in the field and give and digital impression taking, it becomes clear their students the opportunity to learn what they will In restorative dentistry for example, improvement that the procedure involving intraoral scanners need after graduation. of accuracy is a topic of high importance, since a like the 3M ESPE Lava Chairside Oral Scanner precise fit of a restoration contributes decisively C.O.S. has several advantages as opposed to When new curricula for dental education are to its long-term success. However, the question impressions taken with trays and polyether or being developed, it is also important to know that arises whether the implementation of digital tech- vinyl polysiloxane materials. For example, the pro- digital technologies have transformed the way nologies does indeed lead to higher precision of cess is faster, just as easy, and highly precise. In information is obtained in everyday life. Therefore, processes in the dental practice and laboratory. addition, some challenges associated with tradi- the learning behaviour of individuals has changed The current advantages of digital techniques, tional impressions such as the dimensional stabil- as well. Reading books and listening to a lecture their future potential and the measures that still ity of the material and compatibility with model for more than an hour is not what young individu- have to be taken in order to benefit from it are materials like gypsum are eliminated. It is still a als are used to do. Modern students like to be discussed in the following article. matter of opinion if the technique is indeed better educated as entertainment, when they do not like than the traditional one, but it does already lead to Impression taking highly satisfying results. Other advantages arise from the digital workflow beginning with impres- Since they belong to the most recent innovations sion taking and ending with milling of the restora- for the dental practice, taking a closer tion. Material-related factors influencing accuracy look at intraoral scanners and e.g. the expansion of gypsum during model their capability to enhance the production, deformation of a bite registration and quality and fit of a restoration imprecision of the wax set-up due to relaxation of may be particularly interesting. the material are not relevant here. First considerations to take optical impressions in the patient s mouth were published by Prof. New approaches to dental education Francois Duret in For successful implementation of intraoral scanning 1973 in his thesis technologies or even complete digital workflows in titled The Optical the dental practice and laboratory, however, it is Dental education with a simulator. Prof. Dr. Albert J. Feilzer, Dean of the Academic Center for Dentistry Amsterdam. No. 23 FEB 2013

17 Espertise magazine Training course at the Academic Center for Dentistry Amsterdam. 17 the lecture they want to zap to another channel, however for lecturing that is not possible. Thus, education for this new generation of students should become edutainment in order to successfully impart knowledge to them. This approach of offering edutainment and using technologies that are new for dental practices is followed at the Academic Center for Dentistry Amsterdam (ACTA). For example, students currently learn intraoral scanning techniques using the Lava C.O.S. In the near future it will be possible to import the captured data into their simulator with haptic burs (Simodont), where tooth preparation skills are acquired before the techniques are used on patients. The simulator uses force sensors for realistic rendering of drill and contact forces. The hardness of different tooth structures like enamel, dentin and the pulp has been replicated as well. Thereafter, the scans of the real treatment will not only be used for the production of a restoration but also to compare the preparation executed in the simulator with the real one. In this way, the evaluation of the student's skills will be more objective. Need for infrastructure This simulator is only one example showing that digital dentistry involves much more than CAD/ CAM processes. Together, the available technologies have a huge potential of leading to increased efficiency of processes and improved quality of treatment not only by employing them at university, but also through their use in the dental practice. kynny istockphoto.com Standardized interfaces are needed to connect different digital technologies with each other. In order to make full use of this potential, however, some work still needs to be done: complete compatibility (standardization) of data produced in different digital systems is important to ensure quick exchange of all available data between treatment partners. This undisturbed transfer of digital information which has to be made possible through standardization of data formats will be the first step towards the development of a digital system that integrates the whole oral care process. After successful integration of all available technologies, e.g. data from the practice management system could be directly imported into the intraoral scanning system. Furthermore, optical impressions could be matched with digital or conventional radiographs or real masticatory movements simulated in a threedimensional model of the patient to evaluate the shape of a planned restoration. Interruptions of the digital process e.g. through use of a physical model would no longer be required in this future workflow. Another prerequisite for this, however, is a powerful infrastructure to facilitate data transfer via secure channels and make it possible to store large amounts of digital information. This is important for universities as well as for every dental practice. In order to help accelerate this development, the ACTA has become part of a consortium of organizations that has set itself the target of building up a national infrastructure for digital dentistry in the Netherlands. If other countries follow this scanrail istockphoto.com Infrastructure for data storage and secure channels for date transfer will help accelerate further development of digital dentistry. example, the way will soon be paved for digital dentistry to become an integrated process that leads to improved quality of dental care including much more than restorations with perfect margins.

18 Clinical Excellence 3M ESPE Lava Ultimate CAD/CAM Restorative A conservative approach to indirect restorations Paulo Monteiro, Caparica, Portugal 18 Figure 1: Initial situation: insufficient glass ionomer filling on a maxillary right second premolar. The goal is to achieve maximum preservation of natural tooth structure and to avoid damaging the periodontium. Figure 2: Tooth preparation for an overlay. The preparation margin is created at or above the level of the soft tissue. Figure 3: Application of 3M ESPE Astringent Retraction Paste prior to impression taking. The paste leads to gingival retraction and a clean, dry sulcus for a precise reproduction of marginal details. Figure 4: Scanning of the preparation using the CEREC Bluecam (Sirona Dental Systems). Figure 5: Milled overlay made of 3M ESPE Lava Ultimate CAD/CAM Restorative in the shade A2 HT (high translucency). Figure 6: Removal of the sprue and polishing with Renfert Opal L Polishing Paste (Renfert). Figure 7: Final polish using a Soft-Chamois Polishing Brush (VH Technologies). A natural, lasting glossy surface is obtained. Figure 8: Finished overlay made of the new resin nano ceramic. Apart from polishing, no further steps are necessary to obtain this beautiful result. Figure 9: Due to the beneficial properties of the material such as very low antagonist wear and good polish retention, extensive characterization or individualization is not necessary and even possible after restoration placement. Paulo Monteiro DMD, MSc Assistant Professor, Oral Rehabilitation Department Instituto Superior de Ciências da Saúde Egas Moniz Caparica Portugal No. 23 FEB 2013

19 Espertise magazine 19 Figure 10: Sandblasting of the inner surface of the overlay with aluminium oxide. This procedure is recommended to increase the bond between the restoration and the adhesive. Figure 11: Application of 3M ESPE Scotchbond Universal Adhesive on the sandblasted surface of the restoration. Figure 12: 3M ESPE Scotchbond Universal Adhesive is applied on the prepared tooth. In this case, the selective enamel etching technique is used, since in this way the highest bond strengths are obtained. Figure 13: Intraoral application of 3M ESPE RelyX Ultimate Adhesive Resin Cement in the shade Translucent (TR). Figure 14: Situation after placement of the resin nano ceramic restoration. A natural gloss is obtained. Figure 15: In order to achieve an even better optical integration, it is decided to characterize the overlay intraorally using white and brown pigments (Kolor + Plus Resin Colour Modifier, Kerr). Figure 16: Final result after sandblasting of the occlusal surface of the restoration and subsequent application of 3M ESPE Scotchbond Universal Adhesive, the pigments and a thin layer of 3M ESPE Filtek Supreme XTE Flowable Restorative.

20 Country Insights Dentistry in the Kingdom of Belgium Bart Soetaert, Ternat, Belgium 20 In the Kingdom of Belgium, a degree in dentistry can be obtained at five different dental treatments are covered by the national insurance. Since these basic costs are covered by the insur- ees. What is also highly interesting is that dental hygienists are by law prohibited in Belgium: only schools. Two of them are located in Flanders, ance independent of the institution that provides it dentists are allowed to work in the oral cavity. As two in Wallonia and one in Brussels. At the (private practice versus policlinics), most patients dental practitioners, we hope that this situation Flemish universities, students have to pass choose to receive dental care in practices, where will change, because we are convinced of the an entrance exam, while there is no such the quality of treatments is high. Approximately positive impact of dental hygienists work on the restriction at the French-speaking universities. In order to obtain a degree as a Master of Bart Soetaert oral health of patients and the efficiency of our practices. Science in dentistry, five years of combined theoretical and practical dental training at university are required. Afterwards, one year of practical training has to be followed. Only then, registration with the Federal Ministry of Health is possible in order to obtain a license to practice the profession. 25% of the patients in Belgium have After graduation, specialist training can be under- an additional private insurance which taken in orthodontics and periodontology, how- is becoming increasingly popular ever, the proportion of specialized dentists is low this is also the case in my two twin in the country: 7,878 general dentists and only practices in Ternat (near Brussels) 137 periodontists and 398 orthodontists were and Melle (near Ghent) in Flanders. registered in 2011 according to the Federal Public Service (FPS) Health, Food Chain Safety and Environment. Many general dentists follow postgraduate training which is offered in endodontics, Dental workforce and practice organization The dental practice in Ternat, Belgium. My own business model is slightly different. In implantology, paediatric dentistry and aesthetic In 2011, approximately 45% of the 8,300 dentists 2008, I have established a twin practice with two dentistry. Continuing education is mandatory in in Belgium were female. In the younger age locations. Each of the five dentists works in both order to keep the accreditation. groups, however, the proportion of women is locations, since we have different special interests much larger (almost 70%) (FPS Health, Food (e.g. I have completed postgraduate education in Insurance system Chain Safety and Environment). prosthodontics and aesthetic dentistry) and we want our patients in Melle and Ternat to benefit Public health insurance in Belgium is financed by Within the country, the single practice remains the from this knowledge. The treatment focus is on taxes paid by the citizens, the amount of payment most popular business model with 83.5% of all prevention, endodontics, periodontics, prostho- being dependent on their income. Patients have to dentists having adopted it. Only 16.5% work in dontics as well as aesthetic and paediatric den- pay for all dental services directly and then claim joint practices. 43% of all dentists work with an tistry. For implant surgery, orthodontic treatments reimbursement from the insurance. A large pro- assistant and in more than 40% of the cases, the and periodontal surgical procedures, patients are portion of the fees for basic treatment, such as dentists with a single practice work with their wife referred to partner practices. Together, three paediatric dentistry, prevention and conservative as an assistant due to the high costs of employ- assistants support us in the two locations. No. 23 FEB 2013