Wear of Glass-ceramic-veneered Zirconia Posterior FPDS After 10 Years

Abstract BackgroundThe abrasion behavior of various ceramics is rarely investigated, though it is relevant for the clinical success of such restorations. The aim of this in vivo study was to evaluate the wear of glass-ceramic-veneered zirconium oxide frameworks over a period of 10 years.MethodsThe abrasive behavior of the restorations was examined in a total of 15 patients after a period of 3, 5, and 10 years using plaster models, which were then subjected to a scanning process on the Atos II industrial scanner and digitized for three-dimensional evaluation of the abrasion by the corresponding software (ATOS Professional 7.6). The individual post-examination models were compared to the baseline model and deviations calculated in the sense of the largest, punctual loss of material in millimeters ("minimal distance"), the average abrasion in millimeters ("mean distance"), and the volume decrease in cubic millimeters ("integrated distance"). Statistical analyses were performed using the Wilcoxon sign rank test or mixed regression models. Multiple testing was considered by Benjamini-Hochberg correction. The significance level was set at 0.05.ResultsWe found steadily increasing wear of the ceramic. The average volume decrease was significant (P < 0.001) at 3 years and 10 years (-3.25 mm3 and − 8.11 mm3, respectively).ConclusionsDespite the increasing wear of the glass-ceramic-veneered zirconium oxide frameworks in this study, the use of this class of materials can be regarded as clinically acceptable.This study is registered in DRKS - German Clinical Trials Registerwith the Register number 00021743

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Wear of glass-ceramic-veneered zirconia posterior FPDs after 10 years

10.21203/rs.3.rs-41587/v2 ◽

2020 ◽

Author(s):

Ragai Edward Matta ◽

Constantin Motel ◽

Elena Kirchner ◽

Simon Stelzer ◽

Werner Adler ◽

...

Keyword(s):

Glass Ceramic ◽

Multiple Testing ◽

Clinical Success ◽

Three Dimensional ◽

Rank Test ◽

Minimal Distance ◽

Significance Level ◽

The Individual ◽

Volume Decrease

Abstract Background: The abrasion behavior of various ceramics is rarely investigated, though it is relevant for the clinical success of such restorations. The aim of this in vivo study was to evaluate the wear of glass-ceramic-veneered zirconium oxide frameworks over a period of at least 10 years.Methods: The abrasion behavior of 15 bridge constructions from 15 different participants was examined after a period of 3, 5, and 10 years using plaster models, which were then subjected to a scanning process on the Atos II industrial scanner and digitized for three-dimensional evaluation of the abrasion by the corresponding software (ATOS Professional 7.6). The individual post-examination models were compared to the baseline model and deviations calculated in the sense of the largest, punctual loss of material in millimeters ("minimal distance"), the average abrasion in millimeters ("mean distance"), and the volume decrease in cubic millimeters ("integrated distance"). Statistical analyses were performed using the Wilcoxon sign rank test or mixed regression models. Multiple testing was considered by Benjamini-Hochberg correction. The significance level was set at 0.05.Results: We found steadily increasing wear of the ceramic. The average volume decrease was significant (P < 0.001) at 3 years and 10 years (-3.25 mm3 and -8.11 mm3, respectively).Conclusions: The results of this study indicate that the rate of volume loss in glass-ceramic-veneered zirconia frameworks in the posterior region increases significantly over time. An increasing frequency of parameters was observed, particularly in the second half of the study period. However, the use of this class of materials can be considered clinically acceptable.

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Wear of feldspathic-ceramic-veneered zirconia posterior FPDs after 10 years

10.21203/rs.3.rs-41587/v3 ◽

2020 ◽

Author(s):

Ragai Edward Matta ◽

Constantin Motel ◽

Elena Kirchner ◽

Simon Stelzer ◽

Werner Adler ◽

...

Keyword(s):

Multiple Testing ◽

Clinical Success ◽

Three Dimensional ◽

Rank Test ◽

Minimal Distance ◽

Significance Level ◽

Mixed Regression ◽

The Individual ◽

Volume Decrease

Abstract Background: The abrasion behavior of various ceramics is rarely investigated, though it is relevant for the clinical success of such restorations. The aim of this in vivo study was to evaluate the wear of feldspathic-ceramic-veneered zirconium oxide frameworks over a period of at least 10 years.Methods: The abrasion behavior of 15 bridge constructions from 15 different participants was examined after a period of 3, 5, and 10 years using plaster models, which were then subjected to a scanning process on the Atos II industrial scanner and digitized for three-dimensional evaluation of the abrasion by the corresponding software (ATOS Professional 7.6). The individual post-examination models were compared to the baseline model and deviations calculated in the sense of the largest, punctual loss of material in millimeters ("minimal distance"), the average abrasion in millimeters ("mean distance"), and the volume decrease in cubic millimeters ("integrated distance"). Statistical analyses were performed using the Wilcoxon sign rank test or mixed regression models. Multiple testing was considered by Benjamini-Hochberg correction. The significance level was set at 0.05.Results: We found steadily increasing wear of the ceramic. The average volume decrease was significant (P < 0.001) at 3 years and 10 years (-3.25 mm3 and -8.11 mm3, respectively).Conclusions: The results of this study indicate that the rate of volume loss in feldspathic-ceramic-veneered zirconia frameworks in the posterior region increases significantly over time. An increasing frequency of parameters was observed, particularly in the second half of the study period. However, the use of this class of materials can be considered clinically acceptable.This study is registered in DRKS - German Clinical Trials Register with the register number 00021743.

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Wear of feldspathic-ceramic-veneered zirconia posterior FPDs after 10 years

BMC Oral Health ◽

10.1186/s12903-020-01336-8 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Ragai-Edward Matta ◽

Constantin Motel ◽

Elena Kirchner ◽

Simon Paul Stelzer ◽

Werner Adler ◽

...

Keyword(s):

Multiple Testing ◽

Clinical Success ◽

Three Dimensional ◽

Rank Test ◽

Minimal Distance ◽

Significance Level ◽

Mixed Regression ◽

The Individual ◽

Volume Decrease

Abstract Background The abrasion behavior of various ceramics is rarely investigated, though it is relevant for the clinical success of such restorations. The aim of this in vivo study was to evaluate the wear of feldspathic-ceramic-veneered zirconium oxide frameworks over a period of at least 10 years. Methods The abrasion behavior of 15 bridge constructions from 15 different participants was examined after a period of 3, 5, and 10 years using plaster models, which were then subjected to a scanning process on the Atos II industrial scanner and digitized for three-dimensional evaluation of the abrasion by the corresponding software (ATOS Professional 7.6). The individual post-examination models were compared to the baseline model and deviations calculated in the sense of the largest, punctual loss of material in millimeters (“minimal distance”), the average abrasion in millimeters (“mean distance”), and the volume decrease in cubic millimeters (“integrated distance”). Statistical analyses were performed using the Wilcoxon sign rank test or mixed regression models. Multiple testing was considered by Benjamini-Hochberg correction. The significance level was set at 0.05. Results We found steadily increasing wear of the ceramic. The average volume decrease was significant (P < 0.001) at 3 years and 10 years (− 3.25 mm3 and − 8.11 mm3, respectively). Conclusions The results of this study indicate that the rate of volume loss in feldspathic-ceramic-veneered zirconia frameworks in the posterior region increases significantly over time. An increasing frequency of parameters was observed, particularly in the second half of the study period. However, the use of this class of materials can be considered clinically acceptable. Trial registration This study is registered in DRKS - German Clinical Trials Register with the register number DRKS00021743. https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00021743

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In-Vivo Degradation Behavior and Osseointegration of 3D Powder-Printed Calcium Magnesium Phosphate Cement Scaffolds

Materials ◽

10.3390/ma14040946 ◽

2021 ◽

Vol 14 (4) ◽

pp. 946

Author(s):

Katharina Kowalewicz ◽

Elke Vorndran ◽

Franziska Feichtner ◽

Anja-Christina Waselau ◽

Manuel Brueckner ◽

...

Keyword(s):

Three Dimensional ◽

Bone Substitutes ◽

Magnesium Phosphate ◽

Degradation Behavior ◽

Micro Computed Tomography ◽

Calcium Magnesium ◽

Interest In Research ◽

In Vivo Degradation ◽

Volume Decrease

Calcium magnesium phosphate cements (CMPCs) are promising bone substitutes and experience great interest in research. Therefore, in-vivo degradation behavior, osseointegration and biocompatibility of three-dimensional (3D) powder-printed CMPC scaffolds were investigated in the present study. The materials Mg225 (Ca0.75Mg2.25(PO4)2) and Mg225d (Mg225 treated with diammonium hydrogen phosphate (DAHP)) were implanted as cylindrical scaffolds (h = 5 mm, Ø = 3.8 mm) in both lateral femoral condyles in rabbits and compared with tricalcium phosphate (TCP). Treatment with DAHP results in the precipitation of struvite, thus reducing pore size and overall porosity and increasing pressure stability. Over 6 weeks, the scaffolds were evaluated clinically, radiologically, with Micro-Computed Tomography (µCT) and histological examinations. All scaffolds showed excellent biocompatibility. X-ray and in-vivo µCT examinations showed a volume decrease and increasing osseointegration over time. Structure loss and volume decrease were most evident in Mg225. Histologically, all scaffolds degraded centripetally and were completely traversed by new bone, in which the remaining scaffold material was embedded. While after 6 weeks, Mg225d and TCP were still visible as a network, only individual particles of Mg225 were present. Based on these results, Mg225 and Mg225d appear to be promising bone substitutes for various loading situations that should be investigated further.

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Modeling the Efficacy of Oncolytic Adenoviruses In Vitro and In Vivo: Current and Future Perspectives

Cancers ◽

10.3390/cancers12030619 ◽

2020 ◽

Vol 12 (3) ◽

pp. 619 ◽

Cited By ~ 1

Author(s):

Mary K. McKenna ◽

Amanda Rosewell-Shaw ◽

Masataka Suzuki

Keyword(s):

Immune Responses ◽

Clinical Success ◽

Three Dimensional ◽

Model Systems ◽

Gene Therapies ◽

Oncolytic Adenoviruses ◽

Limited Success ◽

Clinical Models

Oncolytic adenoviruses (OAd) selectively target and lyse tumor cells and enhance anti- tumor immune responses. OAds have been used as promising cancer gene therapies for many years and there are a multitude of encouraging pre-clinical studies. However, translating OAd therapies to the clinic has had limited success, in part due to the lack of realistic pre-clinical models to rigorously test the efficacy of OAds. Solid tumors have a heterogenous and hostile microenvironment that provides many barriers to OAd treatment, including structural and immunosuppressive components that cannot be modeled in two-dimensional tissue culture. To replicate these characteristics and bridge the gap between pre-clinical and clinical success, studies must test OAd therapy in three-dimensional culture and animal models. This review focuses on current methods to test OAd efficacy in vitro and in vivo and the development of new model systems to test both oncolysis and immune stimulatory components of oncolytic adenovirotherapy.

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A CBCT evaluation of molar uprighting by conventional versus microimplant-assisted methods: an in-vivo study

Dental Press Journal of Orthodontics ◽

10.1590/2177-6709.23.3.35.e1-9.onl ◽

2018 ◽

Vol 23 (3) ◽

pp. 35.e1-35.e9

Author(s):

Sergio Martires ◽

Nandini V. Kamat ◽

Sapna Raut Dessai

Keyword(s):

Prospective Study ◽

Three Dimensional ◽

Vertical Plane ◽

Statistical Analyses ◽

Significance Level ◽

Second Molar ◽

Dimensional Effects ◽

The Mean

ABSTRACT Objective: The aim of this prospective study was to compare the three-dimensional effects of the conventional helical uprighting spring (CA) and the mini-implant assisted helical uprighting spring (MIA), using CBCT scans. Methods: Twenty patients with mesially tipped second mandibular molars were divided into two groups: CA group, in which 10 patients were treated using a conventional helical uprighting spring with conventional anchorage; and MIA group, in which 10 patients were treated using a mini-implant supported uprighting spring. Molar uprighting was observed in both groups for a period of four months. Two standardized 11×5-cm CBCT sections of the mandible were taken, being one prior to uprighting and one at the end of the four month follow-up. Statistical analyses at the beginning of treatment and after a 4 month follow-up were performed, with a significance level of p< 0.05. Results: The mean amount of change in mesiodistal angulation in the MIA group was 8.53 ± 2.13o (p< 0.001) and in the CA group was 9.8 ± 0.5o (p< 0 .001). Statistically significant differences were found between the two groups with regard to buccolingual inclination of canine, first and second premolars (p< 0.05), second molar (p< 0.001) and extrusion of second molar (p< 0.05). Conclusions: The mean amount of change in the mesial angulation of the second molar in the CA as well as the MIA groups was similar. MIA, which used mini-implant as a source of anchorage, was more effective in preventing movement of the anchorage teeth as well as preventing extrusion of the second molar in the vertical plane, when compared to the CA group, which used dental units as a source of anchorage.

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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Three-Dimensional Subcellular Organization of Hepatocytes in Intact Liver: Simultaneous Visualization of Cytoskeletal and Membrane Markers by Confocal Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163903 ◽

1996 ◽

Vol 54 ◽

pp. 288-289

Author(s):

Greg V. Martin ◽

Ann L. Hubbard

Keyword(s):

Three Dimensional ◽

Integral Membrane Proteins ◽

Polarized Secretion ◽

Microscope Images ◽

Computer Aided ◽

Intracellular Organelles ◽

Cytoskeletal Elements ◽

Simultaneous Visualization

The microtubule (MT) cytoskeleton is necessary for many of the polarized functions of hepatocytes. Among the functions dependent on the MT-based cytoskeleton are polarized secretion of proteins, delivery of endocytosed material to lysosomes, and transcytosis of integral plasma membrane (PM) proteins. Although microtubules have been shown to be crucial to the establishment and maintenance of functional and structural polarization in the hepatocyte, little is known about the architecture of the hepatocyte MT cytoskeleton in vivo, particularly with regard to its relationship to PM domains and membranous organelles. Using an in situ extraction technique that preserves both microtubules and cellular membranes, we have developed a protocol for immunofluorescent co-localization of cytoskeletal elements and integral membrane proteins within 20 µm cryosections of fixed rat liver. Computer-aided 3D reconstruction of multi-spectral confocal microscope images was used to visualize the spatial relationships among the MT cytoskeleton, PM domains and intracellular organelles.

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