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Objectives: To evaluate and compare an experimental surgical navigation system (ESNS) in implant placement accuracy to static planning and transfer systems. Material and Methods: Partially edentulous, surgical typodonts were used to simulate prosthetically-driven osteotomies in preclinical setting. After cbCT acquisition the DICOM files were used to reverse plan and fabricate surgical guides. Manual placement, three static guiding systems and ESNS were compared. Eight osteotomies per jaw were transferred to 10 typodonts in five series, resulting in 400 osteotomies by 3 operators, each modality. Lateral, vertical, total and angular deviations were measured and compared. Results: Computer-assisted systems were comparable and provided superior precision laterally and in angulation, but not vertically; implants placed in free-end positions were less accurate. Conclusions: All computer-aided methods showed less than 2 mm or 5 degrees error on average, which needs to be considered in clinical practice.

Objectives: To evaluate and compare an experimental surgical navigation system (ESNS) in implant placement accuracy to static planning and transfer systems. Material and Methods: Partially edentulous, surgical typodonts were used to simulate prosthetically-driven osteotomies in preclinical setting. After cbCT acquisition the DICOM files were used to reverse plan and fabricate surgical guides. Manual placement, three static guiding systems and ESNS were compared. Eight osteotomies per jaw were transferred to 10 typodonts in five series, resulting in 400 osteotomies by 3 operators, each modality. Lateral, vertical, total and angular deviations were measured and compared. Results: Computer-assisted systems were comparable and provided superior precision laterally and in angulation, but not vertically; implants placed in free-end positions were less accurate. Conclusions: All computer-aided methods showed less than 2 mm or 5 degrees error on average, which needs to be considered in clinical practice.

Aim: To investigate retrospectively the outcome of surgical peri-implantitis treatment taking potentially relevant parameters into account. Material and method: Patients being treated for peri-implantitis during 2013-2019 by a single specialist with sufficient radiographic and clinical documentation and at least a nine-month follow-up were considered herein. Patient-, prosthodontic-, and implant-related data were collected from the journals and available radiographs at baseline and follow-ups. Surgical procedures were divided into open flap debridement (OFD), resective, regenerative and combined treatments. Treatment outcome was defined as: good (PPD≤5mm+no BoP); acceptable (PPD>5mm without BoP or BoP+PPD≤5mm); bad (PPD>5mm+BoP and/or suppuration); and failure (explantation or re-operation). Descriptive statistics, chi-square or Fisher’s exact test were performed to assess potential predictors for the combined outcomes good and acceptable, coined as “successful”, and bad and failure, coined as “unsuccessful”. Results: Thirty-seven patients and 69 implants with a follow-up of 9 to 63 months fulfilled the inclusion criteria. Overall, 71% of the treated implants showed a good outcome and 13% an acceptable outcome, i.e., in 84% of the cases a successful outcome was achieved. Regenerative treatment had the highest success rate (87%) followed by resective (84%), OFD (83%) and combined treatment (83%). One of the predictors (i.e., smoking) affected the successful outcome negatively with >10%. However, statistical analysis failed to prove significance. Conclusion: Based on this retrospective analysis of a relatively limited number of implants, surgical treatment of peri-implantitis was successful in 84% of the cases. For defining risk factors affecting the treatment outcome a larger sample size is required. The results were of no statical significance. / Syfte: Retrospektivt undersöka resultatet av kirurgisk peri-implantitbehandling med hänsyn till potentiellt relevanta parametrar. Material och metod: Alla patienter som kirurgiskt behandlades för peri-implantit under tidsperioden 2013-2019 av en enda specialist med minst nio månaders uppföljning beaktades här. Patient-, protes- och implantatrelaterade data samlades in retrospektivt från journaler och tillgängliga röntgenbilder pre- och postoperativt. Kirurgiska ingrepp delades in i open flap debridement (OFD), resektiv, regenerativ och kombinerad behandling. Behandlingsresultatet definierades som: good (PPD≤5mm+ingen BoP); acceptable (PPD>5mm utan BoP, eller BoP+PPD≤5mm); bad (PPD>5mm+BoP och/eller suppuration); och failure (explantering eller re-operation). Beskrivande statistik, chi-square eller Fisher’s exact test utfördes för att bedöma potentiella prediktorers påverkan på resultatet. För ”lyckat” kombinerades resultaten good och acceptable, medan för ”misslyckat” kombinerades resultaten bad och failure. Resultat: Trettiosju patienter och 69 implantat med en uppföljning på 9 till 63 månader uppfyllde inklusionskriterierna. Sammantaget visade 71% av de behandlade implantaten ett bra resultat och ytterligare 13% ett acceptabelt resultat, dvs. i 84% av fallen uppnåddes ett lyckat resultat. Regenerativ behandling hade den bästa lyckandefrekvensen (87%) följt av resektiv (84%), OFD (83%) och kombinerad behandling (83%). En av prediktorerna, mer specifikt rökning, påverkade lyckandefrekvensen negativt med >10%. Statistisk analys misslyckades dock med att bevisa statistisk signifikans. Slutsats: Baserat på denna retrospektiva analys av ett relativt begränsat antal implantat lyckades kirurgisk behandling av peri-implantit i 84% av fallen. För att definiera riskfaktorer som påverkar behandlingsresultatet krävs en större provstorlek. Resultaten visade ingen statistisk signifikans.

Background and Aim: „CI-Wizard“ is a new, three-dimensional software planning tool for cochlear implant surgery with manual and semi-automatic algorithms to visualize anatomical risk structures of the lateral skull base preoperatively. Primary endpoints of the study represented the evaluation of the CI Wizards usability, accuracy, subjectively perceived and objectively measured time in clinical practice. Materials and Methods: In a period from January 2014 to March 2015, n=36 participants were included in this study. These members were divided into three groups of equal number (n=12), but different level of experience. Senior doctors and consultants (group 1), residents (group 2) and medical students (group 3) segmented twelve different CT-scan data sets of the CI Wizard (four per participant). In total, n=144 data sets were collected. The usability of the CI Wizard was measured by the given questionnaire with an interval rating scale. The Jaccard coefficient (JT) was used to evaluate the accuracy of the anatomical structures segmented. The subjectively-perceived time was measured with an interval rating scale in the questionnaire and was compared with the objectively mean measured time (time interact). Results: Across all three groups, the usability of the CI Wizard has been assessed between 1 ('very good') and 2 ('with small defects'). Subjectively, the time was stated as 'appropriate' by questionnaire. Objective measurements of the required duration revealed averages of n=9.8 minutes for creating a target view. Concerning the accuracy, semi automatic anatomical structures such as the external acoustic canal (JT=0.90), the tympanic cavity (JT=0.87), the ossicles (JT=0.63), the cochlea (JT=0.66) and the semicircular canals (JT=0.61) reached high Jaccard values, which describes a great match of the segmented structures between the partcipants and the gold standard. Facial nerve (JT=0.39) and round window (JT=0.37) reached lower Jaccard values. Very little overlap tendency was found for the chorda tympani (JT=0.11). Conclusion: This software program represents a further important step in the development of pre-operative planning tools in cochlear implant surgery. The study revealed a high level of satisfaction in the usability. The subjectively required time was considered as „appropriate“ and the objectively mean measured time was n=9.8 minutes short enough, so that a clinical application seems realistic. Particularly for semi-automatically segmented structures, it represented a good accuracy. For purely manual segmented structures, further improvements are desirable. Finally, this program also provides a good learning tool for medical students and residents to become familiar with the anatomy of the lateral skull base.:1 Einführung 1 1.1 Cochlea Implantate (CI) 1 1.2 Bildverarbeitungsprogamme zur präoperativen Planung eines Cochlea Implantates 2 1.2.1 Segmentierung in der Medizin 2 1.2.2 CI-Wizard 4 1.3 Fragebogen 6 1.4 Zielsetzung 6 1.5 Zusammenfassung der Ergebnisse 7 2 Publikation 8 3 Zusammenfassung 19 4 Literaturverzeichnis 23 Anlagen 26 Beitrag der Promovendin bei geteilter Erstautorenschaft 34 Erklärung über die eigenständige Abfassung der Arbeit 35 Lebenslauf 36 Danksagung 37

Extrações de terceiros molares inferiores e colocações de implantes são cirurgias comuns na prática clínica Odontológica que podem proporcionar, mesmo com as devidas precauções, a parestesia. A terapia de fotobiomodulação com laser de baixa potência estimula a reparação tecidual a partir da absorção dessa luz pelo tecido irradiado. Essa terapia pode ser realizada com a aplicação do laser sobre trajetória do nervo comprometido (laserterapia) ou, sobre pontos de acupuntura da face (laseracupuntura). Este ensaio clínico randomizado, cego, controlado, em paralelo, avaliou o retorno sensitivo do nervo alveolar inferior quando utilizadas uma das duas técnicas de fotobiomodulação em pacientes com parestesia, pós-extração de terceiros molares inferiores ou cirurgia de implantes. Foram selecionados 60 participantes que tiveram a deficiência sensitiva, após o procedimento cirúrgico, acometendo o nervo alveolar inferior. Os participantes da pesquisa foram aleatoriamente divididos em três grupos (n=20): Grupo 1 - medicação sistêmica - composto de ribonucleotídeos pirimidínicos, uridina trifosfato trissódio, citidina monofosfato dissódio (ETNA®, 01 cápsula de 8/8 hrs, 30 dias); Grupo 2 - laserterapia - 808 nm, 100 mW, 40s/ponto, 4 J de energia/ponto, distância de 1 cm entre cada ponto de irradiação, intra e extra-oral, modo contínuo, diâmetro do feixe de 0,0434 cm2 no trajeto do laser alveolar inferior lado comprometido; Grupo 3 - laseracupuntura - irradiação nas mesmas condições que grupo 2, porém apenas na região extra-oral, nos pontos de acupuntura do lado comprometido: E-4 (dicang), M-CP-18 (Jiachengjiang), VC-24 (chengjiang), E-5 (daying), E-6 (jiache) e ponto A1 (YNSA). Em seguida, foram submetidos a um protocolo padronizado de avaliação, que consistiu em 6 testes de limiares de: percepção de parestesia; térmica ao quente/frio; percepção mecânica vibratória; discriminação de dois pontos; percepção de superfície de dor e tatil. A avaliação do grupo 1 foi realizada na primeira sessão clínica (pré-intervenção terapêutica), imediatamente após a finalização da intervenção da medicação sistêmica (após 4 semanas) e 1 mês após o término das intervenção (após 8 semanas da primeira avaliação). Os Grupo 2 e 3 foram avaliados na primeira sessão clínica (pré-intervenção terapêutica), após 10 sessões de tratamento (5 semanas) e após 20 sessões de tratamento (10 semanas da primeira avaliação). Os dados coletados nas avaliações foram transcritos para fichas específicas e considerados para análise estatística. O único limiar que apresentou efeito de interação entre grupo e tempo (primeira, segunda e terceira avaliação) foi o limiar de percepção de parestesia, p=0,002. A partir de Tukey foi constatada diferença estatistica significante entre os grupos nos testes de limiares de percepção: térmica ao frio (grupo 1=3; 1 ?2; 2=3), p=0,04; de superfície de dor na mucosa anterior (grupo 1=2=3), p=0,04; corpo mandibular posterior (grupo 1=2; 1?3,2=3), p=0,01; lábio (grupo 1=2;1?3; 2?3), p=0,04; e mento (grupo 1=2;1?3;2?3), p=0,05. Não foram encontradas outras diferenças significativas nos outros testes de comparação de grupo. Tais resultados apontam que ambas as terapias de fotobiomodulação foram benéficas no tratamento de parestesia. / Mandibular third molar extractions and implant surgeries are common in the dental clinical practice and can promote, even with precautions, paresthesia. Photobiomodulation Therapy (PBMT) using low power laser stimulates tissue repair due to the absorption of light. The PBMT can be performed with the laser application over the entire trajectory on the compromised nerve (laser therapy) or only in acupuncture\'s face points (laser acupuncture). This randomized, blinded, parallel, controlled trial study aimed to evaluate the sensitive return when one of the two PBM techniques were used in patients with paresthesia caused by mandibular third molar extraction or implant surgery. Sixty volunteers reporting sensory deficiency on the inferior alveolar nerve were selected. Volunteers were randomly divided into three groups (n=20): Group 1 - systemic medication: pyrimidine ribonucleotides, uridine triphosphate trisodium, dissodium cytidine monophosphate (ETNA®, 01 capsules, 8/8 hrs, 30 days); Group 2 - laser therapy: 808 nm, 100 mw, 40s /point, 4 J energy /point, 1 cm distance between each irradiation point, intra- and extra-oral, continuous mode, beam diameter of 0.0434 cm2, following the injured alveolar laser pathway; Group 3 - laseracupuncture: irradiated in the same conditions as group 2, but only at the extra-oral region, in acupuncture points of the compromised side: E-4 (dicang), M-CP-18 (Jiachengjiang), VC-24 (chengjiang), E-5 (daying), E-6 (jiache) e ponto A1 (YNSA). Then, volunteers underwent a standardized protocol of evaluation, which consisted of 6 tests: test of perception of paresthesia; thermal perception (hot/cold); mechanical vibration perception; two-point discrimination test; and threshold of pain and tatil surface perceptions. Group 1 was evaluated at the first clinical session (pre-intervention), immediately after the end of the intervention (after 4 weeks) and 1 month after the end of the intervention (after 8 weeks of the first evaluation). Groups 2 and 3 were evaluated at the first clinical session (pre-intervention), after 10 treatment sessions (5 weeks) and after 20 treatment sessions (10 weeks of the first evaluation). The data collected in the evaluations were transcribed for specific records and considered for statistical analysis. The only threshold that presented interaction effect between group and evaluation (first, second and third) was the perception threshold of paresthesia, p = 0.002. From Tukey statistically significant difference was found between the groups in the tests of perception thresholds : thermal to cold (group 1 = 3; 1 ? 2; 2 = 3), p = 0.04; of surface of anterior mucosal pain (group 1 = 2 = 3), p = 0.04; posterior mandibular body (group 1 = 2; 1 ? 3,2 = 3), p = 0.01; lip (group 1 = 2; 1 ? 3; 2 ? 3), p = 0.04; (group 1 = 2; 1 ? 3; 2 ? 3), p = 0.05. No other significant differences were found between the groups in other tests. These results indicate that both photobiomodulation therapies have been beneficial in the treatment of paresthesia.

The implant surgery replaces missing tooth to regain functionality and look of the normal tooth after dental operation. Improper placement of implant increases recuperation periods and reduces functionality. The aim of this thesis is to design a passive haptic robotic arm to guide dentist during the implant surgery. In this thesis, the optimum design of the 6R passive haptic robotic arm is achieved. The methodology used in optimization problem involves minimization of end-effector side parasitic forces/torques while maximizing transparency of the haptic device. The transparency of haptic device is defined as realism of forces generated by device in real world compared to forces in virtual world. The multivariable objective function including dynamic equations of 6R robotic arm is derived and the constraints are determined using kinematic equations. The optimization problem is solved using SQP and GA. The link lengths and other relevant parameters along with the location of tool path are optimized. The end-effector parasitic torques/forces are significantly minimized. The results of two optimization techniques have proven to be nearly the same, thus a global optimum solution has been found in the search space. Main contribution of this study is to take spatial nonlinear dynamics into consideration to reduce parasitic torques. Also, a mechanical brake is designed as a passive actuator. The mechanical brake includes a cone based braking system actuated by DC motor. Three different prototypes are manufactured to test performance of the mechanical brake. The final design indicates that the mechanical brake can be used as passive actuators.

Les objectifs de cette thèse étaient de1/ carctériser la douleur post-opératoire chez des patients ayant reçu un implant dentaire mandibulaire. 2/examiner la relation entre facteurs individuels, facteurs chirurgicaux et douleurs post-operatoire chez patients ayant reçuun implant dentaire mandibulaire. 3/déterminer les incidences de la douleur neuropathique chez des patients ayant reçu un implant dentaire mandibulaire.Cette thèse a montré que la douleur post-opératoire aigüe après un implant dentaire allait d'une intensité douce à modérée((inférieur à 3 sur l'échelle visuelle analogique) et de courte durée. Une anlyse univariée a montré que l' intensité de la douleur post-operatoire était en lien avec l'âge, le souvenir de la douleur ayant fait suite à une précédente chirurgie orale, le nombre d'implants et la distance entre la fraise et le canal neurologique alvéolaire inférieur(IAN). En revanche aucun lien n'a été démontré avec le sexe, des facteurs psychologiques ou le procédé chirurgical. Une analyse multivariée a montré une association significative entre une douleur post-opératoie aigüe et la distance entre l'implant et le canal neurologique alvéolaire inférieur mémoire de la douleur après une précédente chirurgie orale. / This prospective study investigates the clinical characteristics and time course of postoperative pain after placement of dental implants in the mandible over a 6-month period. We also examined the influence of preoperative physical and psychological factors, as well as surgical factors, on acute postoperative pain. Postal questionnaires built to assess the existence neuropathic features of pain at the site of surgery (with the Douleur Neuropathique 4 Questions [DN4]) were sent two weeks, and one, three and six months after surgery.Acute postoperative pain was of mild-to-moderate intensity and had a short duration. Univariate analyses showed that the intensity of postoperative pain was related to age, remembrance of pain after a previous oral surgery, the number of implants, and the distance between the drill and the inferior alveolar nerve (IAN) canal. But, there was no relationship with gender, psychological factors, or surgical procedure (buccal flap). Besides the number of implants (P=0.013), and the distance between the end of the drill and the IAN canal (P=0.004), multivariate analyses showed a significant interaction between the acute postoperative pain and: i) the distance between the implant and the IAN canal (P=0.0005), ii) remembrance of pain after a previous oral surgery (P=0.003), iii) previous oral surgical pain (P=0.005). Among the patients who completed follow-up, only 0.7% (n = 1) scored positive on neuropathic symptoms (DN4 ≥ 3).This prospective observational study provides the characteristics of acute postoperative pain after placement of dental implants in the mandible and the risk factors for developing severe oral postoperative pain. It also provides the incidence rate of neuropathic pain occurring within the 6 months after dental implant surgery.

Image segmentation plays an important role in medical image analysis. Many segmentation algorithms exist. Most of them produce data which are more or less not suitable for further surface extraction and anatomical modeling of human tissues. In this thesis, a novel segmentation technique based on the 3D Delaunay triangulation is proposed. A modified variational tetrahedral meshing approach is used to adapt a tetrahedral mesh to the underlying CT volumetric data, so that image edges are well approximated in the mesh. In order to classify tetrahedra into regions/tissues whose characteristics are similar, three different clustering schemes are presented. Finally, several methods for improving quality of the mesh and its adaptation to the image structure are also discussed.

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