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UNIVERSITY HOSPITAL

Psychogenic impact/quality of life andcomplementary medical procedures indental questionsPI: Prof. Dr. S. EitnerThis area of research is divided in two main focalpoints. The first focal point evaluates psychoge-nic influence on treatment planning and out-come of dental disease patterns with a psycho-genic background. Among other factors, thesubject’s appraisal of his own body can influ-ence dental questions. Besides, the etiologicalcorrelation of gag reflexes during dental treat-ment, the influence of stress and clinical pictureson fear, depressive states, and social parametersare evaluated, too.The second focal point concerns the therapeuticintervention with medical hypnosis and acu-puncture in dental treatment and their influ-ence on psycho-social factors as well as pain inabove mentioned dental problems.

Optical 3D-measurement technique indentistryPI: Dr. R. Matta, L. WolfQuantitative assessment of biomechanical ef-fects in vivo intraorally required highly complexresearch set-ups due to lack of adequate mea-surement technology in the past. The aim of theresearch group is to establish and evaluate full-field three-dimensional (3D) optical inspectionsystems for clinical application in biomechanicresearch. The system will allow real time quan-titative depiction of biomechanical influences inthe oral cavity. 3D-image correlation providesstrain measurements in all dimensions which arecritical for accurate strain and loading responsemeasurements in objects. The results of theseoptical measurements are compatible with finiteelement analysis software and facilitate verifica-tion and iteration of models that cannot be usedsolely to draw general conclusions regardingspecific questions related to biomechanics. Thesystem available at the Department of Prostho-dontics uses photogrammetric principles. Rele-vant parameters for future in vivo applicationswere identified in current and completed studies, and first in vivo applications revealedpromising results.

CAD/CAM research laboratoriesPI: Dr. R. Matta, ZA G. SkibinskiIndustrial CAD/CAM manufacturing technolo-gies have gained significant market share in pro-ducing dental restorations in recent years, pri-marily due to standardized product quality andprecision as well as economic processing rou-tine in dental laboratories. To achieve high qual -

Dental biomechanicsPI: PD Dr. M. KarlMechanical parameters of the components usedare decisive co-factors determining long-termtreatment outcomes in implant dentistry. Duringthe past year, an in vitro study measuring micro-motion between implants and abutments wasconducted using a specially designed test setup.Clinical failures such as fractured implants are ofgreat importance in this context as they allow foranalyzing potential design and material relatedissues. Using a clinically fractured diameter re -duced screw-type implant, the possibilities offractographic analysis were shown. Broadeningthe potential applications of the recently devel -oped diagnostic tool for quantifying bone qualityon the basis of intraoperative compressive test -ing, finite element analyses were performed sim -ulating an acetabular cup endoprosthesis.

In vitro test setup for measuring micromotion between im-plant and abutment

Finite Element Analysis showing an acetabular cup endo-prosthesis under torsional load

SEM image showing the fracture surface of a clinically failed dental implant

AddressGlückstraße 1191054 ErlangenPhone: +49 9131 8533604Fax: +49 9131 8536781www.prothetik.uk-erlangen.de

DirectorProf. Dr. med. dent. Manfred Wichmann

ContactClaudia EhrhardtPhone: +49 9131 8533604Fax: +49 9131 8536781claudia.ehrhardt@uk-erlangen.de

Research Focus• Dental biomechanics• Psychogenic influence/quality of life and com-plementary medical procedures in dentalquestions

• Optical 3D-measurement technique in den -tistry

• CAD/CAM research laboratories• Prosthodontics and implant therapy based on3D-imaging

Structure of the Department

Professorships: 1Personnel: 50• Doctors (of Medicine): 19• Scientists: 13 (thereof funded externally: 0)• Graduate students: 10

Clinical focus areas• Implant prosthetics• Fixed and removable prosthetic• Diagnosis and treatment of temporomandibu-lar joint dysfunction (TMJD)

• Hypnosis and acupuncture treatment • Esthetic dentistry• Prosthetic rehabilitation with epithesis• Prosthetic rehabilitation of children

Research

Due to the high demands and quality standardsof research projects, synergistic effects of highlyqualified specialists are mandatory. This is re-flected in the general orientation and a focus onfuture demands as well as in extensive cooper -ation with other fields of research. One keyfocus of research is the aging population andthe resulting demographic changes and the in-vestigation of the relationship between oral andgeneral health.

Department of ProsthodonticsChair of Dental, Oral, and Maxillofacial Medicine – especially Prosthetic Dentistry

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of dental restoration will be taught only exem-plarily.A unique opportunity for all dental students atthe FAU Dental School is the opportunity to par-ticipate in a three-year extra-curricular implantprogram. The ”i.Lect” program is funded bythird parties and provided in cooperation withthe Department of Oral and Cranio-Maxillofa-cial Surgery. The i.Lect program has become anessential part of the elective and interdiscipli-nary education of dental students. The first stu-dents passed successfully their examination in2012 and finished their i.Lect pre-graduate pro-gram and started the post-graduated programwhich is also provided in cooperation with theDepartment of Oral and Cranio-MaxillofacialSurgery.The Department of Prosthodontics supervisesMD theses.

Selected PublicationsKarl M. In vitro studies on CAD/CAM restorations fabrica-ted with Procera technology: an overview. QuintessenceInt. 2015; 46(7): 561-574

von Wilmowsky C, Bergauer B, Nkenke E, Neukam FW,Neuhuber W, Lell M, Keller A, Eitner S, Matta RE. A new,highly precise measurement technology for the in vitroevaluation of the accuracy of digital imaging data. J Cra-niomaxillofac Surg. 2015; 43(8):1335-1339

Nickenig HJ, Wichmann M, Eitner S,Zöller JE, Kreppel M.Lingual concavities in the mandible: a morphological studyusing cross-sectional analysis determined by CBCT. J Cra-niomaxillofac Surg. 2015; 43:254-259

Matta RE, von Wilmowsky C, Neuhuber W, Lell M, NeukamFW, Adler W, Wichmann M, Bergauer B. The impact of dif-ferent cone beam computed tomography and multi-slicecomputed tomography scan parameters on virtual three-dimensional model accuracy using a highly precise ex vivoevaluation method. J Craniomaxillofac Surg. 2016 ;44(5):632-636

Nkenke E, Agaimy A, Vairaktaris E, Lell M, von WilmowskyC, Eitner S .Case History Report: Immediate Rehabilitationwith a Prefabricated Fibula Flap Following Removal of a Lo-cally Aggressive Maxillary Tumor. Int J Prosthodont. 2016Jan-Feb;29(1): 53-58

Schmitt CM, Matta RE, Moest T, Humann J, Gammel L,Neukam FW, Schlegel KA. Soft tissue volume alterationsafter connective tissue grafting at teeth: the subepithelialautologous connective tissue graft versus a porcine colla-gen matrix - a pre-clinical volumetric analysis. J Clin Peri-odontol. 2016; 43(7):609-617

International CooperationsProf. T.D. Taylor, Prof. J.R. Kelley, PhD, University of Con-necticut, Farmington: USA

Dr. H. Leblebicioglu, PhD, Erciyes University, Kayseri: Tur-key

ity and precision, product aligned processroutes are a mandatory prerequisite. The re-search group focuses on segmenting CAD/CAMprocesses and assessment of the impact on theoverall quality. In addition to recently developedmethodologies for 3D-display and analysis ofmicrogaps in conventional dental restorations,new protocols are in development for a clinicalassessment of fit of implant retained super-structures. The research laboratories are equippedwith state-of-the-art industrial non-contactscanners and necessary analytical software pro-grams. As high strength oxide ceramics are ap-plied more frequently as framework materials indentistry, several research projects assess theclin ical application and factors influencing long-term success.

Prosthodontics and implant therapybased on 3D-imagingPI: Dr. R. Matta, L. Wolf, Dr. C. MotelThe three dimensional imaging becomes moreand more important for the modern implantand prosthodontic therapy plan. This includesthe Computer Tomography (CT), the ConeBean Computer Tomography (CBCT) and theintraoral digital impression.Two research groups handle this research topic;the first one is concerned with the digital intra -oral impression taking and compares it with theconventional method. The second group fo -cuses on the three dimensional accuracy of theX-ray imaging. In addition the impact of differ -ent dental implant materials on the appearanceof artifacts in the three-dimensional virtualmodel is investigated by this group.In this context a new method for the three-dimensional evaluation of CT and CBCT imageshas been developed. The research in this area is of great importanceand interest because the long-term clinical suc-cess of prosthodontic and implant restorationsdepends on the accuracy of the three dimen -sional transfer of oral structures in “virtual” illus-trations.

Teaching

The main focus of traditional prosthodonticeducation has shifted from a technically ori-ented towards an interdisciplinary treatment ap-proach. Prophylaxis and biology are in the focusas well as minimally invasive treatment con-cepts. Clinically relevant topics are introducedinto the preclinical curriculum, focusing on bio-logic interactions and material properties.While theoretical knowledge remains integralpart of dental education, manual manufacture

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