COMFOUR Special Issue

12 13 now the COMFOUR ™ System, regarding sourc- es of error. We were therefore able to resolve as a team all those surgical and prosthetic difficulties that arose. MDT S. Schuldes, M.Sc.: When providing treatment using the Maló concept, you must un- derstand the principle and have a precise under- standing of the prosthetic challenges you will face. Pre-implantation planning taking into account the surgical and prosthetic requirements is given special priority. Computer-aided, three-dimensional planning in the form of backward planning has proven its worth here. The implants can be posi- tioned in the planning software in the precise 0°, 17°, or 30° angle relative to one another. From the prosthetic perspective, it is particularly important to position the implants so that the screw chan- nels of the screw-retained immediate restoration – but even more importantly those of the subse- quent definitive restoration – do not negatively impact either the esthetics or the function. On this basis, we then fabricate a CAD/CAM bridge from a polymer that is bonded free of tension in the mouth of the patient following the fully gui- ded insertion of the implants using the CAMLOG ® Guide System. In our opinion, this procedure in- volves considerably fewer compromises than the traditional procedure in which impressions are tak- en of the inserted implants intraoperatively and a temporary restoration is then prepared using cold- curing acrylic resin. How often did something go wrong? Dr. F. Steidl: The implant loss rate during the healing phase with VARIO SR in our patient pop- ulation does not differ significantly from that of other implant treatment modalities. We will defi- nitely be able to maintain this success rate using the COMFOUR ™ System. The COMFOUR ™ System offers us even more treatment options. We do not consider there to be an increased risk associated with fully guided, immediate temporary restora- tions after 3D planning. Tricky and important is the question regarding the reproducible fixation of the drill templates in- traorally if provisional implants are not used. We had a considerable learning curve in this area go- ing from fixation by the assistant to osteosynthesis screws to multiple template operations. MDT S. Schuldes, M.Sc.: As already mentioned, thorough planning prior to the implantation is very important. A fracture in the immediate resto- ration can also lead to complications during the osseointegration. In light of this, materials with a high fracture toughness should be used. This is the only way to reduce failures to a minimum. You actively participated in the develop- ment of the new angled bar abutments in the COMFOUR ™ System and even treated some of the first patients with this system. Could you describe your impressions of the implementation from a surgical and technical perspec- tive, and what are the differences to VARIO SR? Dr. F. Steidl: From a implant surgery perspective, nothing has changed in the treatment sequence. The insertion of the angled bar abutments is fun. This is because of the handle that ensures safe transfer of the abutments into the mouth and makes correct alignment easier. The flexibility of the handle and the help of the sophisticated screw- driver means that the abutment screws can be screwed in without any difficulty. MDT S. Schuldes, M.Sc.: The 17° and 30° angled bar abutments in the A and B versions with various gingival heights provide a generous leeway for the treatment. All the components of the COMFOUR ™ System have a slender design and low profile. This makes the prosthetic resto- ration considerably easier. For improved soft tissue augmentation, the new design of the abutment with the “bend” makes itself felt. Thanks to the impression posts and the titanium caps with the anti-rotation mechanism, occlusal screw-retained single-tooth and telescope restorations at the abutment level are also possible. If the implants are not inserted under full guidance, the new aligning tools to make fine adjustments of the rotation cams during implantation are an excep- tional tool. Will this type of therapy establish itself extensively in practices? Dr. F. Steidl: Certainly not extensively. Angled implantation, where necessary also with an imme- diate restoration, is surgically, prosthetically, and technically demanding. I therefore believe that practices and clinics with a focus on implantology should at least carry out the surgical part. For general practitioners, the COMFOUR ™ System is an interesting option if they are involved in prosthetics. To be able to rehabilitate an edentulous patient not just dentally but also often psychosocially in a single treatment session without repeated impression taking or fittings is an inspirational therapeutic tool. Thank you for the interview. [1] Ledermann, P., D.: Über 20-jährige Erfahrung mit der sofor- tigen funktionellen Belastung von Implantatstegen in der Regio interforaminalis. Z Zahnärztl Implantol 12, 123–136 (1996). [2] Malo P, de Araujo Nobre M, Lopes A, Moss SM, Molina GJ. A longitudinal study of the survival of All-on-4 implants in the mandible with up to 10 years of follow-up. J Am Dent Assoc 2011;142:310–320. [3] Schley J-S, Terheyden H, Wolfart S. Implantatprothetische Versorgung des zahnlosen Oberkiefers S3-Leitlinie AWMF-Regis- ternr. 083–010: DZZ 08/2013. [4] Crespi R, Vinci R, Capparé P, Romanos GE, Gherlone E. A cli- nical study of edentulous patients rehabilitated according to the "all on four" immediate function protocol. Int J Oral Maxillofac Implants. 2012 Mar-Apr;27(2):428-34. The concept popularized by Professor Paulo Maló for occlusal screw-re- tained immediate restorations requires at least four implants in the edentulous lower jaw and edentulous upper jaw. The Implantology Consensus Con- ference recommends six implants in the lower jaw and eight implants in the upper jaw for fixed restorations. Dr. Steidl, what should guide the clinician’s choices here? Dr. F. Steidl : The Consensus Conference draws up principles or guidelines for implantology treatment. In our opinion, these form a therapeutic corridor with flexible limits which vary depending on the individual situation of a patient and/or clinician. For example, the “one implant per tooth” concept favored and publicized by some colleagues for fixed restorations with eight implants in some cas- es and ten or twelve in others must be mentioned. This is contrasted by fixed reconstructions with four implants, which is a therapeutic option that saves both effort and costs. The scientific foundation of these treatment strategies ranges from studies conducted by P. Ledermann on immediate restora- tions on four implants in the interforaminal region in the lower jaw [1] to studies by Professor P. Maló with obliquely inserted distal implants in the up- per and lower jaws [2]. The current S3 guidelines from the DGI/ DGZMK (AWMF REGISTER NO. 083- 010) do not include any recommendations for or against the Maló concept [3]. The authors believe this to be a highly promising approach. We consider the Maló treatment method to be a valid concept for fixed immediate oral rehabilitation in our practice and clinic [4]. Consequently, we provide a full 5-year warranty for restorations using the COMFOUR ™ System, as we do for other implant treatments. Many years ago you and your team started to treat your patients using this concept. How steep was the learn- ing curve for this type of treatment? Dr. F. Steidl: Like every new therapeutic approach, there are details of the surgery and den- tal prosthesis that are only worked out over many treatments. What was surprising to us, however, was the tolerance of the VARIO SR System, and CAMLOG has worked closely with its customers and invested in new machinery in order to expand the range of bar abut- ments by adding angled versions with a slender, pointed design. This new system is called COMFOUR ™ . Dr. Ferenc Steidl and MDT Sebastian Schuldes M.Sc., users during the test phase, were asked by the logo editorial team about their impressions of and their first experience with the new system. FIRST EXPERIENCE WITH THE COMFOUR ™ SYSTEM LITERATURE PRODUCTS PRODUCTS