240 participants attending Osteology Switzerland

The year had just started, when on 12-13 January 2018, the 4th National Osteology Symposium in Switzerland took place. 240 participants, and not only from Switzerland, attended the excellent Scientific Programme on Saturday, 13 January. And also the four Osteology and industry workshops on the pre-congress day on Friday were almost sold out.

The four hands-on workshops on Friday were held by Goran Benic and Nadja Nänni, Simone Janner, Marco Zeltner and Samuel Huber, as well as Beat Wallkam. Each workshop was repeated once to allow participant to attend two different workshops.

A research forum was held on the evening of the pre-congress day, where the best four of the submitted research projects were presented on-stage. The excellent presentation by Lucrezia Paterno Holtzman with the title “Treatment of gingival recession defects using a coronally advanced flap combined with acellular dermal matrix graft in two biotype populations: a controlled clinical study” received the 1st price. The 2nd price was awarded to Jordi Caballé Serrano for his presentation “A novel volume-stable collagen matrix supports fibroblast invasion and proliferation and collagen deposition”. Congratulations to the winners.

In the main programme on Saturday, some of the most renowned experts on oral tissue regeneration from Switzerland were on-stage, as well as international experts, such as Karin Jepsen, Germany, Daniele Cardaropoli, Italy, or Frank Schwarz, Germany. The Chairmen, Daniel Buser and Ronald E. Jung, had put together an excellent programme covering all aspects of oral tissue regeneration therapies. True to the motto of the Osteology Foundation “Linking Science with Practice in Regeneration”, the latest insights from research were presented and their relevance for the practice was highlighted. Unfortunately, Chairman Ronald E. Jung had to stay at home on Saturday due to illness and had to miss the presentations in the outstanding programme that he had helped to set up, and Claude Andreoni took over Jung’s moderation part in addition to his.

The first session addressed the topic soft-tissue management. Anton Sculean talked about different techniques for recession coverages. He explained that Miller Classes I and II are not distinguished anymore. In single recessions he recommended coronally advanced flap (CAF) or tunnel (CAT) technique, without a split-flap in order to avoid perforations. In the lower jaw, 96% coverage can be achieved with a connective tissue graft (CTG) only. He also presented a novel technique with a laterally moved flap, which showed good and predictable results (Sculean & Allen, accepted).

Rino Burkhard presented in the same session different options for soft-tissue harvesting, and discussed which is the best. His answer: it depends on the indication and the patient. He explained about the composition of the tissue in the different areas on the palate, and different harvesting techniques. Based on his long experience and illustrated with cases, he gave several recommendations for the practice, such as that the interposition of a CTG or a collagen matrix enhances the wound stability (Burkhardt et al, 2015). In the case of a buccal recession after tooth extraction, he prefers a CTG to close the augmented extraction socket, since it allows to thicken the tissue on the buccal side at the same time. And a combined, inlay-onlay graft, i.e. with some remaining epithelium, can allow an easier handling and is easier to suture, in particular in vertical augmentations.

Karin Jepsen talked about aesthetics and function in implantology, and whether bone augmentation alone is sufficient. The answer is no. She gave a short introduction into an ongoing multicenter study with a novel collagen matrix in comparison with CTG, and presented 3 clinical cases. Six months after crown placement, 3 mm (transmucosally measured) soft tissue gain was recorded in the two cases treated with the collagen matrix, which is a valuable alternative for soft tissue increase at implants, she explained, since the main drawback of CTG is the limited availability.

Whether autologous bone- and soft-tissue grafts are still necessary, was discussed by Daniel Thoma. For sinus floor augmentations his answer was a clear: autologous bone and bone substitutes lead to comparable implant survival rates. In smaller Guided Bone Regeneration (GBR) cases, he also sees no need for autologous bone. In larger GBR cases, autologous bone is beneficial, but the results are also not very different, and the drawback is the increased morbidity through harvesting. For soft tissue augmentation procedures, novel collagen matrices are an alternative to autologous grafts. There are no significant differences in the treatment results (Sanz et al. 2016), but the morbidity is significantly lower. However, autologous tissue is still the gold standard, Thoma explained.

In the second session, hard-tissue management was addressed. Simone Janner started the session with a presentation about predictable and long-term-stable bone augmentation. The type of approach depends on the type of the defect, he explained: 1-wall defects are more demanding than other defects (3-4-wall defects), and therefore require more complex approaches. The selected approach has to ensure not only long-term stability but also long-term esthetics. The combination of autologous bone and deproteinized bovine bone mineral (DBBM) for bone regeneration has provided good results in terms of long-term stability and aesthetics. He presented an in-vivo study (Janner et al. 2017) comparing the combination of autogenous bone and DBBM (in 2 layers, DBBM covering autologous bone) with and without membrane, as well as DBBM alone with and without membrane. It was observed that autogenous bone has the power to accelerate the formation of new bone and the membrane ensures undisturbed bone regeneration and better volume stability.

Daniele Cardaropli discussed which decisions practitioners have to take at the time of tooth extraction. There is quite a lot of knowledge about the intra-alveolar and extra-alveolar healing process after tooth extraction, he explained, and this helps to make a decision after a tooth is extracted.  Based on this, it is clear that absorption cannot be avoided; however, it can be compensated. It has been demonstrated that spontaneous healing prior to implant placement might compromise the final results. Different approaches based on different timing of implant placement (immediate, early, delayed and late) and the use of biomaterials can be applied in order to meet patient expectations.  The status of the buccal bone and soft tissue have to be considered in order to make a decision about the type of approach. He presented a clinical case classification as decisional tree as follows: if the buccal bone is intact and there is an optimal soft tissue level, immediate implant placement can be done with the following recommendations: 1) flapless extraction, 2) prostetically driven implant placement (the implant should be placed towards the lingual side), 3) grafting of the gap between implant and bone, 4) delivering of immediate restoration in order to ensure the soft tissue contouring. If there are both hard and soft tissue deficiencies at the post-extracted site a staged approach is recommended taking into account that 1) ridge preservation can compensate socket resorption, and 2) that the implant can be placed after 4 to 6 months.
CAD supported techniques for the augmentation of deficient ridge with autologous bone were presented by Martin Rücker. He stressed that it is immanent to plan backwards, i.e. from the final position of the crown via the correct position of the implant to the augmentation of the bone. Different harvesting techniques and areas for autologous bone were presented, and limitations and advantages discussed.

The last presentation was held by Frank Schwarz. He discussed different treatment options for periimplantitis, and when to remove an implant, when to regenerate, and when debridement is sufficient. It mainly depends on the implant surface and the defect type, he explained. Open flap debridement alone is only suitable for machined implants. In implants with rough surfaces, implantoplasty is superior. The success of regenerative approaches is best in intrabony defects, and the outcome is influenced by the defect type, the material used, and the implant surface. Mucosal recessions are always a problem when a flap is raised. He recommended therefore to perform always a simultaneous volume augmentation with a CTG. Combined therapy is indicated in advanced defects with minor mucosal recessions, and a resective therapy in advanced defects, combined with major mucosal recession. The removal of the implant is also indicated in the case of the loss of osseointegration, technical complications, and when complex implant designs are present.

The Osteology Foundation thanks all presenters, moderators, industry partners, exhibitors, participants, and the local organisers, who have made this event such a big success! We are already looking forward to a repetition.

More photos from the event can be found online on THE BOX.