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Unkovskiy A, Spintzyk S, Axmann D, Engel EM, Weber H, Huettig F. Additive Manufacturing: A Comparative Analysis of Dimensional Accuracy and Skin Texture Reproduction of Auricular Prostheses Replicas. J Prosthodont 2017; 28:e460-e468. [PMID: 29125215 DOI: 10.1111/jopr.12681] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2017] [Indexed: 11/29/2022] Open
Abstract
PURPOSE The use of computer-aided design/computer-aided manufacturing (CAD/CAM) and additive manufacturing in maxillofacial prosthetics has been widely acknowledged. Rapid prototyping can be considered for manufacturing of auricular prostheses. Therefore, so-called prostheses replicas can be fabricated by digital means. The objective of this study was to identify a superior additive manufacturing method to fabricate auricular prosthesis replicas (APRs) within a digital workflow. MATERIALS AND METHODS Auricles of 23 healthy subjects (mean age of 37.8 years) were measured in vivo with respect to an anthropometrical protocol. Landmarks were volumized with fiducial balls for 3D scanning using a handheld structured light scanner. The 3D CAD dataset was postprocessed, and the same anthropometrical measurements were made in the CAD software with the digital lineal. Each CAD dataset was materialized using fused deposition modeling (FDM), selective laser sintering (SLS), and stereolithography (SL), constituting 53 APR samples. All distances between the landmarks were measured on the APRs. After the determination of the measurement error within the five data groups (in vivo, CAD, FDM, SLS, and SL), the mean values were compared using matched pairs method. To this, the in vivo and CAD dataset were set as references. Finally, the surface structure of the APRs was qualitatively evaluated with stereomicroscopy and profilometry to ascertain the level of skin detail reproduction. RESULTS The anthropometrical approach showed drawbacks in measuring the protrusion of the ear's helix. The measurement error within all groups of measurements was calculated between 0.20 and 0.28 mm, implying a high reproducibility. The lowest mean differences of 53 produced APRs were found in FDM (0.43%) followed by SLS (0.54%) and SL (0.59%)--compared to in vivo, and again in FDM (0.20%) followed by SL (0.36%) and SLS (0.39%)--compared to CAD. None of these values exceed the threshold of clinical relevance (1.5%); however, the qualitative evaluation revealed slight shortcomings in skin reproduction for all methods: reproduction of skin details exceeding 0.192 mm in depth was feasible. CONCLUSION FDM showed the superior dimensional accuracy and best skin surface reproduction. Moreover, digital acquisition and CAD postprocessing seem to play a more important role in the outcome than the additive manufacturing method used.
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Affiliation(s)
- Alexey Unkovskiy
- Department of Prosthodontics, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
| | - Sebastian Spintzyk
- Medical Material Science and Technology, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
| | - Detlef Axmann
- Department of Prosthodontics, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
| | - Eva-Maria Engel
- Department of Prosthodontics, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
| | - Heiner Weber
- Department of Prosthodontics, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
| | - Fabian Huettig
- Department of Prosthodontics, Tüebingen University Hospital, Tübingen, Baden-Württemberg, Germany
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Kittel G, Axmann D. Deterioration in hearing caused by hearing aids in children? Adv Otorhinolaryngol 2015; 27:130-7. [PMID: 7325055 DOI: 10.1159/000400335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
(1) There were 7 children among 55 afflicted with severe hearing impairment or with residual hearing (approximately 13%) who exhibited mostly unilateral progression which was ascertained by accurate pure tone audiometric tests during an observation period of several years. (2) Instrument-caused deterioration, however, could not be confirmed in these children. Except for 1 case, deterioration was rather attributable to intercurrent diseases and hearing-aid-independent progression. However, a higher sensitivity to additional auditory damage appears to exist. (3) According to the results of the present studies, the use to super-power hearing aids is indicated in cases of residual hearing although the hearing aid should not be used during the period of intercurrent diseases. In early childhood, intensive speech hearing training should in any case be limited to about three periods of 20 min each daily. This also applies when speech is not understood because experience demonstrates that the acquisition of speech rhythms is a major aid in the process of learning to speak.
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Tsiflikas I, Thomas C, Fallmann C, Schabel C, Mangold S, Ketelsen D, Claussen C, Axmann D, Schroeder S, Burgstahler C. Prevalence of Subclinical Coronary Artery Disease in Middle-Aged, Male Marathon Runners Detected by Cardiac CT. ROFO-FORTSCHR RONTG 2015; 187:561-8. [DOI: 10.1055/s-0034-1399221] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- I. Tsiflikas
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - C. Thomas
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - C. Fallmann
- Sports Medicine, University Hospital of Tuebingen, Germany
| | - C. Schabel
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - S. Mangold
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - D. Ketelsen
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - C. Claussen
- Diagnostic and Interventional Radiology, University Hospital of Tuebingen, Germany
| | - D. Axmann
- Center of Dentistry Oral Medicine and Maxillofacial Surgery, University Hospital of Tuebingen, Germany
| | - S. Schroeder
- Internal Medicine, Klinikum am Eichert, Goeppingen, Germany
| | - C. Burgstahler
- Center of Dentistry Oral Medicine and Maxillofacial Surgery, University Hospital of Tuebingen, Germany
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Huettig F, Axmann D. Reporting of dental status from full-arch radiographs: Descriptive analysis and methodological aspects. World J Clin Cases 2014; 2:552-564. [PMID: 25325067 PMCID: PMC4198409 DOI: 10.12998/wjcc.v2.i10.552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Revised: 07/11/2014] [Accepted: 08/31/2014] [Indexed: 02/05/2023] Open
Abstract
AIM: To identify standards, how entities of dental status are assessed and reported from full-arch radiographs of adults.
METHODS: A PubMed (Medline) search was performed in November 2011. Literature had to report at least one out of four defined entities using radiographs: number of teeth or implants; caries, fillings or restorations; root-canal fillings and apical health; alveolar bone level. Cohorts included to the study had to be of adult age. Methods of radiographic assessment were noted and checked for the later mode of report in text, tables or diagrams. For comparability, the encountered mode of report was operationalized to a logical expression.
RESULTS: Thirty-seven out of 199 articles were evaluated via full-text review. Only one article reported all four entities. Eight articles reported at the maximum 3 comparable entities. However, comparability is impeded because of the usage of absolute or relative frequency, mean or median values as well as grouping. Furthermore the methods of assessment were different or not described sufficiently. Consequently, established sum scores turned out to be highly questionable, too. The amount of missing data within all studies remained unclear. It is even so remissed to mention supernumerary and aplased teeth as well as the count of third molars.
CONCLUSION: Data about dental findings from radiographs is, if at all possible, only comparable with serious limitations. A standardization of both, assessing and reporting entities of dental status from radiographs is missing and has to be established within a report guideline.
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Fischer P, Battes S, Axmann D, Engel E. Geschlechtsspezifische Unterschiede bei Haltung und Rückenschmerz an Computer-Arbeitsplätzen. physioscience 2013. [DOI: 10.1055/s-0033-1335468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Lachmann S, Stehberger A, Axmann D, Weber H. The peri-implant health in patients attending an annual recall program. A clinical and microbiological study in 74 patients from the Tübingen Implant Registry. Clin Oral Implants Res 2012; 24:1300-9. [DOI: 10.1111/j.1600-0501.2012.02573.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2012] [Indexed: 11/29/2022]
Affiliation(s)
- Stefan Lachmann
- Department of Oral and Maxillofacial Surgery; Center of Dentistry; Oral Medicine and Maxillofacial Surgery; University Hospital Tübingen; Tübingen Germany
- Department of Prosthodontics and Medical Material Sciences; Center of Dentistry; Oral Medicine and Maxillofacial Surgery; University Hospital Tübingen; Tübingen Germany
| | - Anna Stehberger
- Department of Orthodontics; Center of Dentistry; Oral Medicine and Maxillofacial Surgery; University Hospital Tübingen; Tübingen Germany
| | - Detlef Axmann
- Department of Prosthodontics and Medical Material Sciences; Center of Dentistry; Oral Medicine and Maxillofacial Surgery; University Hospital Tübingen; Tübingen Germany
| | - Heiner Weber
- Department of Prosthodontics and Medical Material Sciences; Center of Dentistry; Oral Medicine and Maxillofacial Surgery; University Hospital Tübingen; Tübingen Germany
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Hansel J, Burgstahler C, Medler S, Axmann D, Niess AM, Tetzlaff K. Effect of simulated diving trips on pulmonary artery pressure in healthy men. Clin Res Cardiol 2012; 101:947-53. [DOI: 10.1007/s00392-012-0482-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 05/30/2012] [Indexed: 10/28/2022]
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Rupp F, Saker O, Axmann D, Geis-Gerstorfer J, Engel E. Application times for the single-step/double-mix technique for impression materials in clinical practice. INT J PROSTHODONT 2011; 24:562-565. [PMID: 22146256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Hydrophilicity of unset impression materials underlies changes occurring during working time. Hence, the clinical application time when impression materials contact oral tissues after mixing may play a critical role in successful impressions. The aim of this study was to analyze the clinical time course of impression taking applying the single-step/double-mix technique. Application times of 86 impressions, comprising 265 prepared teeth and 46 implants, taken by 14 different clinicians at a university dental clinic were analyzed. The mean time from loading the impression tray until its final position in the patient's mouth (total application time) was 51.2 seconds; confidence intervals were 46.9 (lower limit) and 55.5 (upper limit). The number of registered teeth and implants did not influence the duration of impression taking. Related to wettability data, several polyvinyl siloxane impression materials show decreased hydrophilicity with respect to estimated application times. The authors suggest considering clinically relevant application times for impression taking in future in vitro studies on physicochemical characteristics of impression materials.
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Affiliation(s)
- Frank Rupp
- Section Medical Materials and Technology, Department of Prosthodontics, University Hospital Tuebingen, Germany.
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Koos B, Horn H, Schaupp E, Axmann D, Berneburg M. Lip and tongue movements during phonetic sequences: analysis and definition of normal values. Eur J Orthod 2011; 35:51-8. [DOI: 10.1093/ejo/cjr082] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Maiwald C, Axmann D, Grau S. Measurement error in footwear research biomechanics. Footwear Science 2011. [DOI: 10.1080/19424280.2011.614280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Grau S, Krauss I, Maiwald C, Axmann D, Horstmann T, Best R. Kinematic classification of iliotibial band syndrome in runners. Scand J Med Sci Sports 2011; 21:184-9. [DOI: 10.1111/j.1600-0838.2009.01045.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Lachmann S, Laval JY, Axmann D, Weber H. Influence of implant geometry on primary insertion stability and simulated peri-implant bone loss: an in vitro study using resonance frequency analysis and damping capacity assessment. Int J Oral Maxillofac Implants 2011; 26:347-355. [PMID: 21483888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023] Open
Abstract
PURPOSE To investigate the influence of implant geometry on primary stability and on peri-implant bone loss in an in vitro model using the Periotest and Osstell devices. MATERIALS AND METHODS Screw-type implants of various diameters and lengths were inserted into bovine bone blocks of different densities, and the primary insertion stability was recorded. To study the influence of implant geometry on implant stability with different levels of peri-implant bone loss, implants were inserted into acrylic resin blocks to mimic osseointegration, and different amounts of the peri-implant acrylic resin were removed. Measurements with both devices at each millimeter step yielded the threshold for the least detectable attachment loss. RESULTS The predominant factors influencing implant stability were bone quality and attachment loss. Implant type and length exerted some influence on implant stability values, while variations in implant diameter produced only minor alterations in the measurements. In simulations of peri-implant attachment loss, implant stability decreased more dramatically for the shorter and narrower implants. The inclusion of more variables in the analyses resulted in less focused measurements. CONCLUSIONS The results of this study clearly show that the outcome of implant stability assessment depends on environmental factors such as bone quality and implant geometry. While the authors do not recommend the use of the Periotest or Osstell devices for a comparison of the stability of two individual implants, both should be useful to monitor the state of an individual implant over time.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics and Medical Material Sciences, Faculty of Medicine, University Hospital, Eberhard-Karls-University of Tübingen, Germany.
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Boeer J, Mueller O, Krauss I, Haupt G, Axmann D, Horstmann T. Effects of a sensory-motor exercise program for older adults with osteoarthritis or prosthesis of the hip using measurements made by the Posturomed oscillatory platform. J Geriatr Phys Ther 2010; 33:10-15. [PMID: 20503728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
OBJECTIVES To assess changes in balance capacities after a 12-week sensory-motor training program for older adults with osteoarthritis or prosthesis of the hip. BACKGROUND Sensory-motor training is recommended to help aging adults with osteoarthritis maintain activity, avoid injurious falls, and improve functioning. Up to now, however, there has been no standard training protocol for sensory-motor training. METHODS AND MEASURES Thirty-five participants in a hip exercise group who had a mean age of 58 years (SD 12) were quasi-randomized into a training group (TG) and a control group (CG) by the month they applied for the Hip School program. The TG performed balance exercises using balance pads and received Hip School training once a week. The CG did not receive any training intervention. Balance was measured by recording center-of-pressure excursion while participants were in 1-legged stance on the oscillatory Posturomed platform. Outcome measures were the total path of center of pressure on the platform during balance recovery and the percentage of failed attempts. RESULTS The TG had a lower percentage of failed attempts (TG 5%, CG 18%, P = .001) and required fewer balance recovery movements to maintain balance (TG: mean [SD] measurement is 59 [36] mm; CG: 96 [68] mm, P = .036] after completing the 12-week training program. After the training period, participants in the TG compensated better for perturbations in the nondisplaced medial-lateral (ML) direction (pretest [SD] measurement was 48 [18] mm; posttest, 36 [14] mm; P= .001]. CONCLUSIONS Participants could successfully cope with more disturbances and improved their reactions to sudden displacements after training intervention. This exercise setting improves balance abilities and should be included in Hip School programs for patients with osteoarthritis.
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Affiliation(s)
- Johannes Boeer
- Medical Clinic, Department of Sports Medicine, University of Tübingen, Tübingen, Germany.
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Grau S, Maiwald C, Krauss I, Axmann D, Horstmann T. The influence of matching populations on kinematic and kinetic variables in runners with iliotibial band syndrome. Res Q Exerc Sport 2008; 79:450-457. [PMID: 19177946 DOI: 10.1080/02701367.2008.10599511] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The purpose of this study was to assess how participant matching influences biomechanical variables when comparing healthy runners and runners with iliotibial band syndrome (ITBS). We examined 52 healthy runners (CO) and 18 with ITBS, using three-dimensional kinematics and pressure distribution. The study population was matched in three ways and compared with the biomechanical findings: ITBS versus CO I (unmatched), ITBS versus CO II (matched to gender) and ITBS versus CO III (matched to gender height, and weight). The final number of participants in each group was n = 18. The kinematic variables showed a dependency on the matching process. The largest statistically significant differences (after Bonferroni adjustment) in the frontal and transverse planes were between ITBS and CO III (p = .008). Pressure measurements were also dependent on the matching process, with decreasing and nonsignificant differences (p = .006) between ITBS and CO after refining the process (ITBS vs. CO III). The results of this study and the necessity of matching seem to be plausible (lever arms, different running styles). Data matching is important for understanding overuse injuries in running.
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Affiliation(s)
- Stefan Grau
- Department of Sports Medicine, University of Tübingen, Germany.
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Giedke H, Axmann D, Gaertner H, Rein W, Rötzer-Zimmer F. Psychophysiological Predictors of Antidepressant Therapy Response? Pharmacopsychiatry 2008. [DOI: 10.1055/s-2007-1017224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Deuster CV, Axmann D. Zur Objektivität der Hirnstammaudiometrie bei Teilleistungsstörungen (sensorischen Integrationsstörungen)*. Laryngorhinootologie 2008. [DOI: 10.1055/s-2007-997797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lachmann S, Kimmerle-Müller E, Axmann D, Gomez-Roman G, Weber H, Haas R. Reliability of findings around healthy implants in association with oral hygiene measures: a clinical, microbiological, and immunological follow-up in edentulous patients. Clin Oral Implants Res 2008; 18:686-98. [PMID: 17991251 DOI: 10.1111/j.1600-0501.2007.01399.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To assess the performance of clinical, microbiological, and immunological diagnosis of peri-implant health and the influence of professional hygiene measures on them. MATERIAL AND METHODS Twenty-one edentulous patients with oral implants supporting a lower overdenture were followed up over 3 months beginning 1 week before their annual recall visit. Hygiene scores, probing depth, bleeding on probing (BOP), implant stability, gingival crevicular fluid (GCF) volume, sulcular interleukin-1beta (IL-1beta) and prostaglandin E2 (PGE2) concentrations, and relative concentrations of five bacterial species (polymerase chain reaction) were investigated. Measurement variation was assessed as a function of (a) intra- and (b) inter-examiner reliability, (c) inter-implant variation in each patient, (d) time, and (e) effect of hygiene measures by accuracy, repeatability, reproducibility, and visualization with the Bland and Altman Plot. RESULTS Measurement means and accuracy (in parentheses) were as follows: GCF volume 1.5 microl (1.5), Interleukin-1beta 8 ng/ml (26), PGE2 63 ng/ml (185), bacteria sum score 0.2 (0.7), plaque score 1 (1), BOP score 0 (1), Periotest value -4 (3), resonance frequency analysis ISQ 66 (11), and pocket probing depth 2.3 mm (0.7). No finding exhibited any statistically significant measurement variation as explained by accuracy, repeatability, or reproducibility. Bland and Altman Plots revealed insufficient agreement for replicated BOP assessments. A short post-treatment reduction in plaque and BOP scores was visually apparent. Still, professional oral hygiene measures exerted no sustained influence on the clinical and biochemical appearance of the peri-implant tissues. CONCLUSION All findings except BOP showed statistically acceptable repeatability and moderate vulnerability to influences present 'chairside' in clinical practice.
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Affiliation(s)
- Stefan Lachmann
- Department of Oral Surgery, Bernhard Gottlieb University Dental School, Medical University of Vienna, Vienna, Austria.
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Rupp F, Axmann D, Geis-Gerstorfer J. Effect of relative humidity on the hydrophilicity of unset elastomeric impression materials. INT J PROSTHODONT 2008; 21:69-71. [PMID: 18350951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This study aimed to analyze the effect of relative humidity (RH) on the initial hydrophilicity of unset elastomeric dental impression materials. Initial water contact angles were studied on thin unset films of 1 polyether and 4 polyvinyl siloxane (PVS) impression materials at 20%, 50%, and 80% RH by high-resolution drop shape analysis. One of 4 PVS materials reached the polyether's initial hydrophilicity. This PVS showed increased hydrophilicity with increasing RH. The initial hydrophilicity of impression materials can be influenced by the RH level. Accounting for RH will enhance the clinical relevance of hydrophilicity studies.
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Affiliation(s)
- Frank Rupp
- Department of Prosthodontics, Section Medical Materials and Technology, University Hospiral Tuebingen, Germany.
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Grau S, Maiwald C, Krauss I, Axmann D, Janssen P, Horstmann T. What are causes and treatment strategies for patellar-tendinopathy in female runners? J Biomech 2008; 41:2042-6. [DOI: 10.1016/j.jbiomech.2008.03.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2008] [Accepted: 03/12/2008] [Indexed: 10/22/2022]
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Decker EM, Maier G, Axmann D, Brecx M, von Ohle C. Effect of xylitol/chlorhexidine versus xylitol or chlorhexidine as single rinses on initial biofilm formation of cariogenic streptococci. Quintessence Int 2008; 39:17-22. [PMID: 18551212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVES Oral bacteria implying a natural resistance may deteriorate the antibacterial efficacy of chlorhexidine on cariogenic microorganisms. Xylitol, mostly applied via chewing gum, is known to possess favorable plaque-reducing properties. The aim of this study was to investigate the effect of a xylitol rinse formulated as pure solution or combined with chlorhexidine on the viability of Streptococcus sanguis (early colonizer of human teeth) and Streptococcus mutans (the most causal strain for caries) during initial steps of biofilm formation. METHOD AND MATERIALS After exposure to the test solutions, the bacteria suspended in human sterile saliva were allowed to attach to human enamel slides for 60 minutes in a preclinical flow chamber system. The bacterial vitality of suspended and attached cells was monitored using 2 fluorescent DNA stains by epifluorescence microscopy. Further parameters measured were the total bacterial cell counts on enamel slides and growth of suspended streptococci. RESULTS The sensitivity of S mutans to pure chlorhexidine or in combination with xylitol is contrary to the natural resistance of S sanguis to chlorhexidine. The combination of xylitol/chlorhexidine showed a statistically significant antivital effect on S sanguis cells compared to the pure agents xylitol and chlorhexidine. The bacterial cell density on enamel and bacterial reproduction on agar plates were similarly affected by the combination of xylitol/chlorhexidine or the single substances. CONCLUSION The newly discovered synergistic antivital effect of xylitol combined with chlorhexidine may contribute to the favorable potential of xylitol use for the improvement of new formulations of caries-preventive mouthrinses.
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Affiliation(s)
- Eva-Maria Decker
- Department of Conservative Dentistry, School of Dental Medicine, University of Tübingen, Tübingen, Germany.
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Affiliation(s)
- I. Krauss
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
| | - S. Grau
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
| | - S. Rombach
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
| | - P. Janssen
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
| | - C. Maiwald
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
| | - D. Axmann
- Department of Prosthodontics and Section Medical Materials and Technology, University of Tueningen, Germany
| | - T. Horstmann
- Medical Clinic, Department of Sports Medicine, University of Tuebingen, Germany
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Lachmann S, Kimmerle-Müller E, Axmann D, Scheideler L, Weber H, Haas R. Associations between peri-implant crevicular fluid volume, concentrations of crevicular inflammatory mediators, and composite IL-1A ?889 and IL-1B +3954 genotype: A cross-sectional study on implant recall patients with and without clinical signs of peri-implantitis. Clin Oral Implants Res 2007; 18:212-23. [PMID: 17348886 DOI: 10.1111/j.1600-0501.2006.01322.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES To assess possible relationships between peri-implant crevicular fluid (PICF) volumes, biochemical markers of the peri-implant immune response, and periodontitis-associated genotype. MATERIAL AND METHODS PICF samples from 29 implant maintenance patients, 24 wearing overdentures, five having single crowns and bridgework (11 patients with peri-implantitis and 18 individuals with healthy peri-implant conditions), were analyzed for per site and per crevicular-fluid-volume concentrations of interleukin-1beta, plasminogen activator inhibitor type 2, and prostaglandin E2 by ELISA. Associations between the three substance concentrations and to crevicular fluid flow rate were analyzed by linear regression analysis. The possible differentiating influence of the composite interleukin-1A and -1B genotype on the patients' peri-implant health and biochemical inflammatory status was checked formally with t-test statistics and the Wilcoxon' test. One implant per patient was chosen for analysis. RESULTS In patients with healthy peri-implant conditions, genotype-positive individuals showed elevated crevicular fluid flow rates and at the same time reduced mediator concentrations. In patients with an implant affected from peri-implantitis, no statistically significant influence of the periodontitis-associated genotype around the fixture can be stated. There was no statistical difference between per site and per crevicular-fluid-volume concentration analyses. All three mediator concentrations were positively related to each other, while there was a strong negative correlation between crevicular fluid volume and plasminogen activator inhibitor 2 or prostaglandin E2. CONCLUSIONS The Interleukin-1 polymorphism investigated exerted only little influence on the peri-implant crevicular immune response, and this influence appeared to be of limited impact in sites with established peri-implantitis lesions.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics, University of Tübingen, Tübingen, Germany.
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Lachmann S, Kimmerle-Müller E, Gehring K, Axmann D, Gomez-Roman G, Watzek G, Weber H. A comparison of implant-supported, bar- or ball-retained mandibular overdentures: a retrospective clinical, microbiologic, and immunologic study of 10 edentulous patients attending a recall visit. INT J PROSTHODONT 2007; 20:37-42. [PMID: 17319360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
PURPOSE Clinical, microbiologic, and immunologic comparisons of the peri-implant health in edentulous volunteers wearing long-standing implant-supported ball- or Dolder bar-retained mandibular overdentures were performed. MATERIALS AND METHODS Ten age- and gender-matched individuals (mean age, 71 years) with either ball- or bar-retained complete mandibular overdentures, scheduled for an annual implant recall examination, were investigated an average of 7 years after implant placement. Plaque and gingival crevicular fluid samples were obtained from the peri-implant sulcus. The groups were compared with regard to peri-implant probing depth; plaque and bleeding on probing scores; sulcular fluid flow rates; implant stability measurements (Periotest device); relative concentrations of Actinobacillus actinomycetemcomitans, Prevotella intermedia, Fusobacterium nucleatum, Porphyromonas gingivalis, Tannerella forsythensis, and Treponema denticola assessed by polymerase chain reaction analysis; and sulcular concentrations of interleukin-1beta and prostaglandin E2, assessed by enzyme-linked immunosorbent assay. RESULTS No statistically significant differences were found for any of the examined parameters between both study groups. CONCLUSION Within the limitations of this study, both ball attachments and Dolder bars can be recommended for overdenture retention, with either one showing satisfying clinical, microbiologic, and immunologic findings in the peri-implant tissues after several years of service in healthy recall patients with good oral hygiene habits.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics and Dental Material Science, Eberhard-Karls-University, Tuebingen, Germany.
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Mesquita RV, Axmann D, Geis-Gerstorfer J. Dynamic visco-elastic properties of dental composite resins. Dent Mater 2006; 22:258-67. [PMID: 16143383 DOI: 10.1016/j.dental.2005.04.019] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2004] [Revised: 03/17/2005] [Accepted: 04/04/2005] [Indexed: 11/25/2022]
Abstract
OBJECTIVES This study aimed to examine the visco-elastic properties of dental composites by dynamic mechanical analysis under the influence of clinically relevant temperatures and variable frequencies, after being stored in air or distilled water for up to 3 months. METHODS Two direct (Diamond Lite and Grandio) and two indirect (Artglass and Vita Zeta LC) composites were used. Samples were immediately tested (baseline) or stored at 37 degrees C, either in air or distilled water for 1 day, 7 or 90 days before testing. During dynamic testing, elastic modulus, viscous modulus and loss tangent were determined over a frequency range from 0.1 to 10 Hz at constant temperatures between 5 and 55 degrees C. RESULTS Results were analyzed by one-way ANOVA and Turkey's-test. Elastic and viscous moduli were higher for direct than for indirect composites. No such evidence was found for loss tangent. Only the elastic modulus showed statistically relevant differences in the direct and indirect materials groups: Grandio showed higher modulus than Diamond Lite, while Artglass had higher modulus than Vita Zeta LC. The elastic modulus reduced with increasing temperature and decreasing frequency, while the loss tangent showed the opposite trend. The influence of temperature and frequency on viscous modulus was not conclusive. The elastic modulus was more sensitive to moisture than viscous modulus and loss tangent but all three properties showed no overall consistent trend in the results following the storage periods. SIGNIFICANCE Dynamic mechanical analysis was a valuable tool to characterize the visco-elastic properties of dental composites, thus giving us a greater insight into material behavior.
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Affiliation(s)
- Renata V Mesquita
- Department of Prosthodontics, Section Medical Materials and Technology, University Hospital Tuebingen, Osianderstr. 2-8, D-72076 Tuebingen, Germany.
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Abstract
OBJECTIVES The aims of this in vitro study were to evaluate reliability of the Osstell and Periotest devices in the assessment of implant stability and to perform a method comparison. MATERIAL AND METHODS Commercial dental implants were inserted into bovine rib segments of different anatomical origins and densities. Repeated measurements were performed, varying (a) the torque-in force of the devices' attachment screw (the Osstell transducer and the ball attachment, insert for the Periotest device), (b) the insertion site bone quality, and (c) the thread exposure in simulated peri-implant bone defects. RESULTS Both methods were comparably reliable and showed a strong association to each other in the classification of implant stability. As opposed to torque-forced screw attachment, the variations in bone composition, differences in inter-implant stability of adjacent implants, and peri-implant bone reduction were statistically significant for both methods. CONCLUSIONS Both non-invasive diagnostic devices seem to be useful in the long-term follow-up of implant integration.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics, University of Tübingen, Tübingen, Germany.
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Abstract
OBJECTIVE We compared the performance of damping capacity assessment (Periotest device) to resonance frequency analysis (Osstell device) in the assessment of peri-implant bone loss in an in vitro experiment. MATERIAL AND METHODS Screw-type oral implants were polymerized into acrylic blocks. Peri-implant bone loss was simulated by successively removing defined portions of material surrounding the implants in millimeter increments. Measurement values of both devices were compared by assessing the associated measurement errors, by calculating correlation analyses and drawing scatterplots, and by means of regression analysis referring to increasing bone loss. RESULTS Both devices produced comparable results suggesting agreement of the measured implant stability values to the actual loss of peri-implant resin. There was a noticeable correlation of the Periotest and Osstell implant stability values. CONCLUSION The results of this experiment suggest agreement in predicting the actual implant stability with both the instruments with the Osstell instrument being the more precise device.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics, University of Tübingen, Tübingen, Germany.
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Rupp F, Axmann D, Jacobi A, Groten M, Geis-Gerstorfer J. Hydrophilicity of elastomeric non-aqueous impression materials during setting. Dent Mater 2005; 21:94-102. [PMID: 15681007 DOI: 10.1016/j.dental.2004.02.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2003] [Revised: 01/19/2004] [Accepted: 02/19/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVES Clinically relevant accuracy of dental impressions depends on flowing and wetting properties of the applied impression materials. The major objective of this study was to develop an experimental set-up and an analysis strategy for wettability measurements of impression materials during their working time. METHODS High-resolution drop shape analysis was used to study contact angles on thin unset films of two polyether and two vinyl polysiloxane (VPS) impression materials. Qualitative and quantitative analysis of the contact angle evolution in terms of initial values and the equilibrium state of hydrophilicity, as well as in terms of kinetics of hydrophilization were extended using a mathematical model approach. RESULTS Compared to VPS impression materials, polyethers show pronounced and constant initial hydrophilicity throughout prescribed working time. The kinetics of the VPS impression materials towards more hydrophilic equilibrium surface states is very fast compared to polyethers. This possibly balances the disadvantage of the initial VPS impression materials hydrophobicity. Generally, the experimental and analytical methods have proven to yield detailed insights into the wetting characteristics during setting. SIGNIFICANCE Both, high initial and a fast kinetics towards increased hydrophilicity may improve flowing and wetting processes during impression taking. Therefore, time-resolved wettability studies should be regarded when developing advanced impression materials and defining working times. They may supplement rheological studies.
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Affiliation(s)
- Frank Rupp
- Section of Medical Materials and Technology, Department of Prosthodontics and Medical Materials, University of Tuebingen, Osianderstr. 2-8, D-72076 Tuebingen, Germany.
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Kournetas N, Jaeger B, Axmann D, Groten M, Lachmann S, Weber H, Geis-Gerstorfer J. Assessing the Reliability of a Digital Preparation Assistant System Used in Dental Education. J Dent Educ 2004. [DOI: 10.1002/j.0022-0337.2004.68.12.tb03872.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Nikos Kournetas
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Berthold Jaeger
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Detlef Axmann
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Martin Groten
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Stefan Lachmann
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Heiner Weber
- Department of Prosthodontics, Medical Materials, and Technology; University Hospital; Tuebingen Germany
| | - Juergen Geis-Gerstorfer
- Section of Medical Materials and Technology, Department of Prosthodontics; Clinic for Dental, Oral, and Maxillary Medicine; University Hospital; Tuebingen Germany
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Kournetas N, Jaeger B, Axmann D, Groten M, Lachmann S, Weber H, Geis-Gerstorfer J. Assessing the reliability of a digital preparation assistant system used in dental education. J Dent Educ 2004; 68:1228-34. [PMID: 15576811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
Use of a digital preparation assistant system may improve considerably the quality of preclinical dental education, provided the system works reliably. Thus, the purpose of this pilot study was to quantitatively assess the reliability of a new preclinical digital preparation assistant system (PREPassist, KaVo, Germany). The system was used to repeatedly scan four different unprepared and four different prepared teeth both with and without repositioning. Corresponding measurements were made to quantify accuracy, repeatability, and reproducibility. This was done by estimating the measurement error. Based on this estimation, respective limits of agreement were calculated. We used these ranges, along with assessments of the measurement's accuracy, to judge whether the results satisfy our expectations for clinically acceptable measurements. For preclinical laboratory instruction, the results indicate an acceptable accuracy (mean accuracy of 89 microm) of the measurements. This assessment applies as well to repeatability, given by the range of the respective limits of agreement (range <200 microm). However, in the case of reproducibility, the limits revealed discrepancies of practical importance (range >200 microm). Reproducibility of tooth repositioning in the available mounting device is unacceptable for preclinical laboratory instruction because of the observed range >200 microm. Thus, there is a need for the manufacture of new and more reliable mounting devices because reproducibility procedures are mostly encountered in preclinical instruction in restorative techniques. In contrast to reproducibility, accuracy and repeatability are acceptable for practical purposes. Balancing advantages and disadvantages, we conclude that, in general, the PREPassist system delivers reliable results.
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Affiliation(s)
- Nikos Kournetas
- Department of Prosthodontics, Medical Materials, and Technology, Clinic for Dental, Oral, and Maxillary Medicine, University Hospital, Osianderstrasse 2-8, 72076 Tuebingen, Germany
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Groten M, Axmann D. Time needed for data collection in clinical studies on fixed prosthodontics. INT J PROSTHODONT 2004; 17:651-6. [PMID: 15686092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
PURPOSE Realistic appraisals of time and costs are crucial for research grants and financing of clinical studies by sponsors, but little is known about the time actually needed for clinical data collection in dental studies. This survey evaluated the net time of patient contact necessary for collection and documentation of clinical data to establish an empirical base for more efficient study management and budgeting. MATERIALS AND METHODS The time needed for the clinical examination of 41 prosthodontic patients in systematic follow-up was recorded. Examination covered dental status, oral hygiene status, and quality assessment of restorations by modified CDA criteria. Completion of the case report forms, data check, and provisions for data retrieval were also included. The recorded times were analyzed to obtain empirical estimates of the time actually needed for specific examination blocks and to detect potential variables of influence. RESULTS Predominant time records were 5 to 10 minutes for dental status (according to status complexity) or hygiene. The time needed for CDA ranking showed a linear correlation to the number of units, approximately 1 minute each. Documentation times were similar to the total contact times of all examination blocks, between 15 and 30 minutes per patient. CONCLUSION The overall time for collection and documentation of retrievable data is considerable (about 30 minutes, up to 1 hour). The data provide an empirical base for sound managing and budgeting of follow-up periods in clinical investigations, which is of major importance for the quality of clinical data, and thus for the success and value of clinical investigations.
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Affiliation(s)
- Martin Groten
- Department of Prosthodontics, Dental Clinic, University of Tübingen, Germany.
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Lachmann S, Engel EM, Axmann D, Weber H. Radiographic study of changes in the mandibular condyle after implant prosthodontic rehabilitation. INT J PROSTHODONT 2004; 17:565-70. [PMID: 15543912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
PURPOSE The aim of this follow-up investigation was to assess the influence of clinical variables after implant prosthodontic rehabilitation in patients without temporomandibular disorders on alterations of condylar morphology as seen radiographically. MATERIALS AND METHODS In 167 patients, the condylar findings of flattening, erosion, osteophytes, and sclerosis were scored according to severity on rotational panoramic radiographs. Findings were followed up on images taken before and on average 5 years after implant prosthodontic rehabilitation. Changes were analyzed in relation to age, gender, initial radiologic status, and occlusal support pre- and posttreatment, according to Eichner groups, by logistic regression analysis. RESULTS The majority of patients did not show structural alterations over the follow-up period, regardless of whether the condyle was already affected at the outset of the investigation. Condyles unaffected at the time of the first radiograph made up the majority of increases in radiographic score. Flattening and sclerosis were cumulative, whereas erosions and osteophytes had a more transient character. There was no influence of the mentioned clinical or radiographic findings on the development of changes. CONCLUSION Over the investigated period, the incidence of all four noted findings doubled. However, the statistical methods employed could not detect any influence of patient variables or the insertion of implant-retained prosthodontics on the development of condylar changes in this specific patient group. Both assertions reflect the complexity of the topic.
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Affiliation(s)
- Stefan Lachmann
- Department of Prosthodontics and Dental Material Sciences, Center for Oral Medicine and Dentistry, Eberhard Karls University Tübingen, Germany.
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Abstract
Dynamic contact angle analysis (DCA) was used to investigate time-dependent wettability changes of sandblasted and acid-etched commercially pure (cp) titanium (Ti) implant modifications during their initial contact with aqueous systems compared to a macrostructured reference surface. Surface topography was analyzed by scanning electron microscopy and by contact stylus profilometry. The microstructured Ti surfaces were found to be initially extremely hydrophobic. This hydrophobic configuration can shift to a completely wettable surface behavior with water contact angles of 0 degrees after the first emersion loop during DCA experiments. It is suggested that a hierarchically structured surface topography could be responsible for this unexpected wetting phenomenon. Roughness spatial and hybrid parameters could describe topographical features interfering with dynamic wettability significantly better than roughness height parameters. The Ti modifications which shift very sudden from a hydrophobic to a hydrophilic state adsorbed the highest amount of immunologically assayed fibronectin. The results suggest that microstructuring greatly influences both the dynamic wettability of Ti implant surfaces during the initial host contact and the initial biological response of plasma protein adsorption. The microstructured surfaces, once in the totally wettable configuration, may improve the initial contact with host tissue after implantation, due to the drastically increased hydrophilicity.
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Affiliation(s)
- F Rupp
- Department of Prosthodontics and Medical Materials, Section of Medical Materials and Technology, University of Tuebingen, Osianderstr. 2-8, D-72076 Tuebingen, Germany.
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Rupp F, Axmann D, Ziegler C, Geis-Gerstorfer J. Adsorption/desorption phenomena on pure and Teflon AF-coated titania surfaces studied by dynamic contact angle analysis. J Biomed Mater Res 2002; 62:567-78. [PMID: 12221705 DOI: 10.1002/jbm.10198] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
As a result of inflammatory processes, plaque formation on dental titanium implants often leads to clinically pathogenic situations. This special biofilm formation on (bio)materials in contact with saliva is initiated by ionic and protein interactions. In this interfacial process, albumin becomes a main constituent of dental pellicle. Interfacial reactions change the surface characteristics. They determine the following steps of macromolecular adsorption and bacterial adhesion. This work focuses on the dynamic contact angle analysis (DCA), which is a tool for online measurements of dynamic changes of wettability without disturbing the interface during detection. Repeatability of the DCA method has been assessed according to the Bland and Altman method. The kinetics and equilibrium data of shifts in the wetting tension hysteresis indicate ionic influences at the titanium/bovine serum albumin (BSA) interface: the Ca-mediated increase of the BSA adsorption on titanium and the adsorption maximum at the isoelectric point (IEP) of BSA. Ti was surface modified by Teflon AF polymeric coatings. The result of the assessment gives reason to consider Teflon AF as a reference material for DCA repeatability studies. This surface modification caused drastic changes in the dynamic interfacial reactions. Shifts in the wetting tensions during DCA adsorption-desorption experiments clearly demonstrated the partially irreversible adsorption of BSA on Teflon AF. In contrast, reversible adsorption behavior was detected on pure Ti surfaces. These findings strengthen the hypothesis that the analysis of dynamic changes in wetting tension and wetting tension hysteresis is a sensitive analytical method for the detection of dynamic interfacial changes at biomaterial/biosystem interfaces during the initial steps of biofilm formation.
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Affiliation(s)
- F Rupp
- Department of Prosthetic Dentistry, Medical Materials and Technology, University of Tuebingen, Osianderstrasse 2-8, D-72076 Tuebingen, Germany.
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Mayer F, Axmann D, Horstmann T, Martini F, Fritz J, Dickhuth HH. Reciprocal strength ratio in shoulder abduction/adduction in sports and daily living. Med Sci Sports Exerc 2001; 33:1765-9. [PMID: 11581564 DOI: 10.1097/00005768-200110000-00023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Functionally, the shoulder is considered a ball joint, whereby high mobility is attended by low stability. Therefore, muscular balance is decisive for stability. Altered strength ratios are frequently described as "muscular dysbalances" and considered one of the causes of shoulder pathologies, whereby objective quantification is difficult. METHODS In order to quantify physiological muscle balance, the strength ratio of shoulder abduction/adduction (AB/AD) was determined in 166 untrained men (UM) concentrically at 60 degrees.s-1 (LIDO-Active). The influence on this norm of one-sided (25 high-performance (TPH), 18 leisure tennis players (TPL)) and two-sided athletic exercise (32 gymnasts (GY)), altered daily exercise (11 paraplegics with paralysis time < 4 months (PP), 11 paraplegics with paralysis time > 2 yr (PU)), and a combination of altered daily exercise and athletic activity (16 trained paraplegics (PT)) was examined (ANOVA, alpha = 0.05). RESULTS Determination of the AB/AD quotient in UM was 0.82. Shoulder stress in sports led to a decrease in quotients compared with UM because of a relatively increased torque in AD (P < 0.01). At the beginning of a paraplegia, the quotient of AB/AD is elevated (P < 0.05). This altered ratio decreases with duration of paralysis (PU) and athletic activity (PT). CONCLUSION With increased shoulder stress, the altered strength ratios reflect specific requirements of the performance attained. However, the importance of muscular dysbalances for the onset of shoulder complaints must be considered more important than their influence on athletic performance capacity.
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Affiliation(s)
- F Mayer
- Medical Clinic and Policlinic, Department of Sports Medicine, Eberhard-Karls-University of Tübingen, Tübingen, Germany.
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Horstmann T, Mayer F, Heitkamp HC, Merk J, Axmann D, Bork H, Dickhuth HH. [Individual isokinetic strength training in patients with gonarthrosis]. Z Rheumatol 2000; 59:93-100. [PMID: 10868015 DOI: 10.1007/s003930050210] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
PROBLEM To date, therapy of osteoarthritis of the knee is aimed at relieving pain and changing behavior patterns, which usually leads to reduced activity. The weakening of the quadricep's musculature leads to an increase in both joint instability and arthritis. Walking time is prolonged and the pain-induced reaction of knee angle velocity is onset by increased stress on other joints. The progressive muscle atrophy correlates to the degree of pain. The aim of this study was to demonstrate an improvement in strength and pain based on 4-week isokinetic strength training in gonarthritis patients. METHOD During a conservative hospitalization period, isokinetic strength training was performed by 19 randomized patients with gonarthritis in addition to regular physiotherapy. Another 19 patients functioned as a control group. The work was examined at 60 degrees/s and 180 degrees/s and rated using a pain questionnaire at the start and end of the investigation. RESULTS In addition to the expected increase of strength and strength endurance in the test group, the degree of pain could also be statistically significantly decreased compared to the control group. Activities of daily living, such as climbing stairs and standing-up, were also performed more easily. CONCLUSIONS The therapeutic strategy for patients with osteoarthritis of the knee should be reconsidered to include less expensive therapeutic sport measures. Anglo-american and Scandinavian studies support this statement. Overuse and pain can be avoided by precise and low-dose strength training. Objective and reproducible measurements in the patients are essential to make individual training possible.
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Affiliation(s)
- T Horstmann
- Medizinische Klinik und Poliklinik, Abteilung Sportmedizin, Eberhard- Karls- Universität Tübingen
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Abstract
STATEMENT OF PROBLEM Gap measurements along margins are frequently used to assess the quality of single crowns. However, the number of gap measurements required for clinically relevant results in laboratory studies is not known. PURPOSE This study estimated the minimum number of gap measurements on margins of single crowns to produce relevant results for gap analysis. METHODS AND MATERIAL Ten all-ceramic crowns were fabricated on a master steel die. Gaps along crown margins were investigated in a scanning electron microscope on the master steel die without cementation and on replica dies after conventional cementation. Measurements were made in 100 microm steps according to 3 gap definitions. The initial number of measurements per crown (n = 230) was reduced to smaller subsets using both systematic and random approaches to determine the impact on the quality of results. RESULTS On the data of gap definition 1, reduction from 230 to about 50 measurements caused less than +/-5 microm variability for arithmetic means. Analysis of standard errors showed slowly increasing values smaller than 3 microm, both indicating no relevant impact on the quality of results. Smaller data sizes yielded accelerated increase of standard errors and divergent variabilities of mean. The minimum of 50 measurements did not depend on gap definition or on cementation condition. CONCLUSION Fifty measurements are required for clinically relevant information about gap size regardless of whether the measurement sites are selected in a systematic or random manner, which is far more than what current in vitro studies use.
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Affiliation(s)
- M Groten
- Dental Clinic, Department of Prosthodontics, University of Tübingen, Tübingen, Germany.
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Mayer F, Axmann D, Horstmann T, Niess A, Striegel H, Ruf J, Dickhuth HH. Metabolic and cardiocirculatory reactions after concentric and eccentric exercise of the shoulder. Int J Sports Med 1999; 20:527-31. [PMID: 10606216 DOI: 10.1055/s-1999-8846] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Lower metabolic and cardiocirculatory reactions to eccentric compared to concentric exercise are known for large muscle groups. The extent of exercise reaction depends on the muscle mass involved and moreover differs between the various muscle groups, while it is unclear to which extent cardiovascular and metabolic reactions and differences between the types of work exist in the shoulder, also it is not known whether these reactions differ according to training status. Lactate production (LA), heart rate (HR), and blood pressure (BP) were examined following eccentric and concentric shoulder movements in 16 male gymnasts (GN) and 15 male untrained subjects (US). Differentiation was made according to the types of work for peak torque (PT) and local muscle endurance (LME). Following eccentric exercise, the increase of LA and HR was clearly lower than following concentric exercise (p<0.05). No difference was observed between the groups. Diastolic BP showed no changes, whereas systolic BP was higher following concentric exercise. Eccentric PT was higher than concentric PT in GN within a test-retest variability of 15%. LME showed a lower degree of fatigue under eccentric conditions, independent of the group. It is concluded that eccentric exercise of the shoulder leads to lower metabolic and cardiocirculatory reactions than concentric exercise, in spite of higher peak torque and less fatigue. Exercises consisting of a high proportion of eccentric movement may thus be beneficial in the therapy of shoulder complaints, especially in patients with cardiovascular disease.
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Affiliation(s)
- F Mayer
- Medical Clinic and Policlinic, Department of Sports Medicine, Tübingen, Germany.
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von Deuster C, Axmann D. [Reliability of brain stem audiometry in specific learning disorders (disorders of sensory integration)]. Laryngorhinootologie 1995; 74:539-42. [PMID: 7495434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Diagnostic audiological tests performed in ten children from 1985 to 1991 showed remarkable differences between the results of behavioral audiometry (free field or pure tone audiometry) and those of auditory evoked response audiometry. Auditory brainstem response (ABR) was absent in seven children with sensory neural hearing loss. Neuropsychological evaluation was performed on four children, neuropsychological observation was performed on two children, pediatric examination was performed on three children and one child showed signs of neuropediatric disorder. The results of neuropsychological evaluation showed moderate to severe learning disabilities (sensory integration disorders, learning disorders) in all four children tested. Available neuropsychological observation also indicated the presence of sensory integration disorders in two children. Two children had multiple handicaps with cerebral abnormalities, two further children were diagnosed as suffering from "minimal cerebral dysfunction," one of which was mentally retarded. The fact that ABRs were absent in seven children indicates that a response desynchronisation in the auditory pathway may exist in these disorders. Thus, ABR might not be a reliable method for audiological testing in children with learning disabilities or other cerebral dysfunctions, but serves as an adjunct to conventional testing methods.
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MESH Headings
- Audiometry, Evoked Response
- Auditory Pathways/physiopathology
- Auditory Perceptual Disorders/diagnosis
- Auditory Perceptual Disorders/physiopathology
- Brain Damage, Chronic/diagnosis
- Brain Damage, Chronic/physiopathology
- Child
- Child, Preschool
- Deafness/diagnosis
- Deafness/physiopathology
- Diagnosis, Differential
- Education, Special
- Evoked Potentials, Auditory, Brain Stem/physiology
- Female
- Follow-Up Studies
- Hearing Loss, Central/diagnosis
- Hearing Loss, Central/physiopathology
- Humans
- Infant
- Language Development Disorders/diagnosis
- Language Development Disorders/physiopathology
- Learning Disabilities/diagnosis
- Learning Disabilities/physiopathology
- Male
- Neuropsychological Tests
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Affiliation(s)
- C von Deuster
- Abteilung für Phoniatrie und Pdaudiologie der Univ.-HNO-Klinik Würzburg
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Brenner P, Krause-Bergmann A, Axmann D, Berger A. [Fournier gangrene: therapy with a pedicled rectus abdominis flap]. Chirurg 1995; 66:537-40. [PMID: 7607021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This paper describes the technique to reconstruct the genitals after an episode of Fournier's gangrene using the rectus abdominis muscle flap. A 44-year-old diabetic man felt ill with a Fournier's gangrene following inguinal herniotomia. The infection could be treated by aggressive débridement and by muscle flap coverage. Then we reconstructed the genitalia.
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Affiliation(s)
- P Brenner
- Klinik für Plastische, Hand- und Wiederherstellungschirurgie, Medizinische Hochschule Hannover
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Giedke H, Gaertner H, Breyer-Pfaff U, Rein W, Axmann D. Amitriptyline and oxaprotiline in the treatment of hospitalized depressive patients. Clinical aspects, psychophysiology, and drug plasma levels. Eur Arch Psychiatry Neurol Sci 1986; 235:329-38. [PMID: 3527706 DOI: 10.1007/bf00381001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Amitriptyline (AT) and the noradrenaline reuptake inhibiting antidepressant oxaprotiline (OT = hydroxymaprotiline) were compared in 59 primary depressive inpatients in a 4-week double blind parallel group design. In the Hamilton Depression Rating Scale and 2 self-rating scales AT proved to be more efficient than OT, mainly with respect to disturbances of appetite and sleep. Agitated patients receiving OT needed more additional tranquilizing medication. The number of side-effects did not differ. Both drugs increased heart rate and skin resistance level (SRL) to about the same degree and did not influence the number of spontaneous fluctuations of SRL, habituation of SRL orienting responses (OR), frequencies of respiration and blinking. Salivation was temporarily more impaired by AT. All physiological variables differed between patients and 30 healthy controls during the whole 4-week trial. Clinical outcome showed a linear relation to OT plasma levels. For AT a therapeutic window was confirmed for concentrations of AT and its metabolite nortriptyline between 125 and 200 ng/ml. Patients whose SRL-OR habituated rapidly had a better outcome than slow habituators. Urinary excretion of 3-methoxy-4-hydroxyphenylglycol was lower in patients than in controls but could not predict outcome with either drug.
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Abstract
Event-related cortical potentials were recorded in 11 patients with primary depression and 11 healthy control subjects during a serial choice reaction task. Each new trial was voluntarily initiated when the subject pressed a microswitch; an acoustic go or no-go signal followed after a fixed interval. This elicited a Bereitschaftspotential (BP), a contingent negative variation (CNV), acoustically evoked potentials (N1, P2, P3), and a post-imperative negative variation (PINV) in direct succession. These were evaluated conventionally and by principal component analysis (PCA). Patients exhibited significantly longer reaction times and more negative PINVs. BP and CNV did not differ between groups. In conventional amplitude measurement small P3 amplitudes in depressives may be feigned by markedly negative PINVs.
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