Die Autoren danken der Zahntechniker Nicola Lanfranconi zur Herstellung der Master-Referenzmodell und die Alicona Company für ihre anhaltende Unterstützung mit der Verbesserung der Scan-Software.

1. Probenvorbereitung / Basis <ol><li> Tragen Sie eine flache Basis um die Probe. Legen Sie die Probe auf dem Scan-Tisch. Orientieren die Kaufläche der horizontalen Ebene (Fig. 1). </li></ol> 2. Analysis Software <ol><li> Starten Sie das Programm und dann die Labor-Messmodul (Bild 2) </li><li> Positionieren Sie die Probe in der Mitte des Scantisch. </li><li> Wählen Sie den richtigen Vergrößerungslinse. Für große Objekte, wie Rundbogen Scans, verwenden Sie die 5X Ziel. </li><li> Bewegen der Scan-Optik unter Verwendung der 3D-Maus, bis die Oberfläche der Probe wird auf dem Live-Ansichtsfenster (Fig. 3) angezeigt. </li><li> Verwenden Sensorsteuerung, um Belichtung und Kontrast eingestellt, um eine optimale Scan-Parameter zu erreichen. Für Metalloberflächen, verwenden Sie eine Exposition zwischen 400 und 800 Mikrosekunden und einem Kontrast zwischen 0,3 und 0,8 (Abbildung 4). </li><li> Überprüfen Sie die Bildqualität, indem Sie die Taste&quot;Show-Bildqualität in der Live-Vorschau&quot;. </li><li> Stellen Sie die richtigen Parameter im Bereich &quot;Mess-Steuerung&quot;. Die Messtyp ist &quot;3D-Datensatz&quot;; Imagefield-Typ ist &quot;General Imagefield&quot; (Abbildung 5). </li><li> Klicken Sie auf &quot;Neue Imagefield&quot;. </li><li> Definieren Sie die Scanvolumen. Die Software muss die Begrenzungskoordinaten der Maßnahme Lautstärke. <ol><li> Bewegen Sie die Probe in die höchsten und niedrigsten Scan-Ebene, und klicken Sie auf &quot;Hinzufügen Position&quot; an beiden Punkten. Das &quot;Z Range&quot;-Wert zeigt die aktuelle Höhe der Scan-Volumen (Abbildung 6). </li><li> Bewegen Sie die Probe auf die XY Boundings der Scanvolumen. Auf &quot;In Position&quot; auf der X-Achse und Y-Achsenlängen definieren. Die Dimension des Scanvolumen wird auf der Registerkarte &quot;Information&quot; dargestellt und sollten die Abmessungen der Probe von 1 cm in der X-Achse und Y-Achse übersteigt. </li></ol></li><li> Überprüfen Sie die &quot;Punkte&quot;-Nummer. Die Software ist in einer &quot;Imagefield&quot; Abtastung in der Lage Scanoberfläche 100 Millionen Punkten. Die tatsächliche AnzahlPunkte überschreitet diese Grenze. Der Messpunkt Nummer &quot;Dezimieren&quot; von einem &quot;Lateral Downsampling&quot; der Punktgröße. <ol><li> Klicken Sie auf &quot;Erweiterte Einstellungen&quot; (Abbildung 7). </li><li> Bewegen Sie den &quot;Lateral Downsampling&quot; Schieberegler nach rechts, bis die &quot;Punkte&quot;-Nummer wird unter 100 M (Abbildung 7) reduziert. Downsampling reduziert die laterale Auflösung der Oberflächenpunkte, was zu größeren Pixelgröße des gescannten Objektes. Um eine optimale Scanergebnisse zu gewährleisten, wird die vertikale Auflösung erhöht. </li></ol></li><li> Klicken Sie auf &quot;Start Measurement&quot;. Dies wird die &quot;Preview Mode&quot; starten. Die Software führt eine Vorabtastung mit den ausgewählten X-und Y-Achsen-Abmessungen. </li><li> Nach der Prescan abgeschlossen ist, wählen Sie die Region von Interesse. Dies hilft, die Dateigröße und Scan-Zeit (Abbildung 8) zu reduzieren. </li><li> Wählen Sie alle Teile der Prescan mit Ausnahme der Probe und zwei Maß Feldern rund um die Probe, mit der flachen Basis (Abbildung 9). </li><li> Klicken Sie auf &quot;Start&quot;, um den Scanvorgang zu starten. </li><li> Steuern Sie den Scan in der mit der Maus &quot;Imageviewer&quot; und drücken Sie die linke Maustaste (Abbildung 10). </li><li> Schließen Sie das Fenster, und klicken Sie auf &quot;Ansicht Pseudo Color Only&quot;. </li><li> Klicken Sie auf &quot;Einstellungen&quot; und &quot;Pseudo Coloring&quot;, und wählen Sie &quot;Wiederholbarkeit&quot;. </li><li> Stellen Sie die &quot;Max&quot;. Wert auf 0,2 und klicken Sie auf &quot;Übernehmen Range&quot;. </li><li> Steuern Sie die Wiederholbarkeit, sollte es gleich für Bereiche mit der gleichen Steigung und Material sein. Insbesondere sollte die Basis um die Probe eine homogene Wiederholbarkeit (Abbildung 11) anzuzeigen. </li><li> Klicken Sie auf &quot;Datenbank&quot; und speichern Sie den Scan in den entsprechenden Ordner. </li><li> Exportieren Sie die Suche auf verschiedene Dateiformate, wenn nötig. Klicken Sie auf &quot;File/Export/3D Daten As / ....&quot; Das Protokoll kann an dieser Stelle angehalten und später fortgesetzt werden. </li></ol> 3. Differenzanalyse <ol><li> Mit der &quot;3D-Editor&quot; wegschneiden die Basis. Dieser Bereich wird nicht für die Differenz verwendet werdenAnalyse. </li><li> Zu vergleichen und zu analysieren, zwei Scans, starten Sie den &quot;Differenzmessung&quot; Software (Abbildung 12). </li><li> Wählen Sie das zweite Modell zu vergleichen. </li><li> Klicken Sie auf &quot;Automatische Grobausrichtung&quot;, um eine erste Spiel der Modelle durchzuführen. </li><li> Klicken Sie auf &quot;Manuelle Einstellung&quot; und richten Sie die Modelle mit Drehen und Bewegen, bis sie in der gleichen Orientierung (Abbildung 13). </li><li> Klicken Sie auf &quot;Automatische Ausrichtung&quot; und &quot;Apply&quot;, um die beste Passform-Algorithmus für die optimale Modellanpassungs starten. </li><li> Klicken Sie auf &quot;Unterschiede&quot;, um den Unterschied der beiden Karte abgestimmt Modelle zu sehen. </li><li> Wählen Sie einen geeigneten Farbpalette, um die Abweichungen (Abbildung 14) anzuzeigen. Speichern Sie die visuelle Abweichungsmuster als Screenshot für die Analyse. </li></ol> Klicken Sie auf &quot;Statistik&quot;, um die statistischen Werte der Differenzen anzuzeigen. Wählen Sie 1 um die Klassengröße und speichern Histogramm-Daten in eine Textdatei zu statistischen Vergleich (Abbildung 15).

<ol>
	<li>Wettstein, F., Sailer, I., Roos, M., H&#228;mmerle, C. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+study+of+the+internal+gaps+of+zirconia+and+metal+frameworks+for+fixed+partial+dentures.">Clinical study of the internal gaps of zirconia and metal frameworks for fixed partial dentures.</a> Eur. J. Oral Sci. 116 (3), 272-279 (2008).</li><li>Persson, A. S., Oden, A., Andersson, M., Sandborgh-Englund, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Digitization+of+simulated+clinical+dental+impressions:+virtual+three-dimensional+analysis+of+exactness.">Digitization of simulated clinical dental impressions: virtual three-dimensional analysis of exactness.</a> Dent. Mater. 25 (7), 929-936 (2009).</li><li>Del'Acqua, M. A., Arioli-Filho, J. N., Compagnoni, M. A., Mollo, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=de+A+Accuracy+of+impression+and+pouring+techniques+for+an+implant-supported+prosthesis.">de A Accuracy of impression and pouring techniques for an implant-supported prosthesis.</a> Int. J. Oral Maxillofac. Implants. 23 (2), 226-236 (2008).</li><li>Schneider, D., Grunder, U., Ender, A., H&#228;mmerle, C. H. F., Jung, R. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Volume+gain+and+stability+of+peri-implant+tissue+following+bone+and+soft+tissue+augmentation:+1-year+results+from+a+prospective+cohort+study.">Volume gain and stability of peri-implant tissue following bone and soft tissue augmentation: 1-year results from a prospective cohort study.</a> Clinical Oral Implants Research. 22 (1), 28-37 (2011).</li><li>Windisch, S. I., Jung, R. E., Sailer, I., Studer, S. P., Ender, A., H&#228;mmerle, C. H. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+optical+method+to+evaluate+three-dimensional+volume+changes+of+alveolar+contours:+a+methodological+in+vitro+study.">A new optical method to evaluate three-dimensional volume changes of alveolar contours: a methodological in vitro study.</a> Clinical Oral Implants Research. 18 (5), 545-551 (2007).</li><li>Caputi, S., Varvara, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dimensional+accuracy+of+resultant+casts+made+by+a+monophase,+one-step+and+two-step,+and+a+novel+two-step+putty/light-body+impression+technique:+an+in+vitro.">Dimensional accuracy of resultant casts made by a monophase, one-step and two-step, and a novel two-step putty/light-body impression technique: an in vitro.</a> 99 (4), 274-281 (2008).</li><li>Hoyos, A., Soderholm, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+tray+rigidity+and+impression+technique+on+accuracy+of+polyvinyl+siloxane+impressions.">Influence of tray rigidity and impression technique on accuracy of polyvinyl siloxane impressions.</a> Int. J. Prosthodont. 24 (1), 49-54 (2011).</li><li>Luthardt, R. G., Kuhmstedt, P., Walter, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+method+for+the+computer-aided+evaluation+of+three-dimensional+changes+in+gypsum+materials.">A new method for the computer-aided evaluation of three-dimensional changes in gypsum materials.</a> Dent. Mater. 19 (1), 19-24 (2003).</li><li>Mehl, A., Ender, A., M&#246;rmann, W., Attin, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+testing+of+a+new+intraoral+3D+camera.">Accuracy testing of a new intraoral 3D camera.</a> International Journal of Computerized Dentistry. 12 (1), 11-28 (2009).</li><li>Fickl, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dimensional+changes+of+the+ridge+contour+after+socket+preservation+and+buccal+overbuilding:+an+animal+study.">Dimensional changes of the ridge contour after socket preservation and buccal overbuilding: an animal study.</a> J. Clin. Periodontol. 36 (5), 442-448 (2009).</li><li>Vlaar, S. T., vander Zel, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+dental+digitizers.">Accuracy of dental digitizers.</a> Int. Dent. J. 56 (5), 301-309 (2006).</li><li>Ender, A., Mehl, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+complete-arch+dental+impressions:+a+new+method+of+measuring+trueness+and+precision.">Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision.</a> 109 (2), 121-128 (2013).</li><li>Ender, A., Mehl, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Influence+of+scanning+strategies+on+the+accuracy+of+digital+intraoral+scanning+systems.">Influence of scanning strategies on the accuracy of digital intraoral scanning systems.</a> Int. J. Comput. Dent. 16 (1), 11-21 (2013).</li><li>Ender, A., Mehl, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Full+arch+scans:+conventional+versus+digital+impressions--an+in-vitro+study.">Full arch scans: conventional versus digital impressions--an in-vitro study.</a> Int. J. Comput. Dent. 14 (1), 11-21 (2011).</li><li>Meer, W. J., Andriessen, F. S., Wismeijer, D., Ren, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Application+of+intra-oral+dental+scanners+in+the+digital+workflow+of+implantology.">Application of intra-oral dental scanners in the digital workflow of implantology.</a> PLoS One. 7 (8), (2012).</li></ol>

Die Autoren erklären, dass sie keine finanziellen Interessen konkurrierender oder andere Interessenkonflikte.

Genauigkeit ist eine Grundforderung in der Zahnmedizin. Der Referenz Scanner ist in der Lage Scannen kleine und große Objekte mit hoher Richtigkeit und Präzision. Mit der optimalen Scan-Methode können sogar einzelne morphologische detaillierte Zahnoberflächen mit einer hohen Auflösung und Wiederholgenauigkeit gescannt werden. Mit den verschiedenen Vergrößerungsstufen des Scanners können Makro-und Mikro morphologischen Strukturen gewonnen werden. Es ist möglich, eine Vielzahl von Modellmaterialien scannen. <...

Genauigkeit ist ein großes Interesse in vielen Bereichen der Zahnmedizin. Ersetzen Zahnhartsubstanz muss eine exakte Prothese, um die ordnungsgemäße Funktion zu gewährleisten und weitere Zerstörung der Restzahnsubstanz 1,2 verhindern. Festteilprothesen und Totalprothese sind für eine genaue Anpassung an unterstützenden Strukturen wie präparierten Zähnen oder Implantaten 3 besonders kritisch. Deshalb ist eine sehr genaue Wiedergabe erforderlich ist, insbesondere im Bereich der Zahnabdrücke und Zahn Workflow. Aber auch andere Bereiche der zahnärztlichen Behandlung auch von einem echten und präzise metrische Ergebnis profitieren können, um den Behandlungserfolg zu überprüfen und neue Behandlungsstrategien, z. B. Hart-und Weichgewebevermehrung, Erosion und Abrasion Überwachung, Zahnbehandlungen und kieferorthopädische Behandlungen 4,5 bewerten. In vielen dieser Felder aktuellen Validierungsverfahren sind lineare Abstandsmessungen mit Messschieber oder Mikroskope 6,7. Diese MethODS sind nur wenige Messpunkte und begrenzte Daten von dreidimensionalen (3D-) Veränderungen in der Testfläche begrenzt. Neuere Methoden schließen die Messung der optischen oder radiologischen Erfassung der gesamten Oberfläche des Testobjekts 8,9. Hier wird die gesamte Oberfläche oder Volumen wird gemessen und als 3D-Objekt auf dem Computerbildschirm angezeigt. Lineare Messungen möglich sind, sowie Überlagerungen von Modellen aus verschiedenen Scan-Zeiten. Mit dieser Überlagerung ist eine Bewertung der Oberflächenveränderungen bei jedem Scanpunkt möglich. Dies ermöglicht die Möglichkeit der Überwachung eines bestimmten Bereichs oder Anzeige Verformungen in alle drei Koordinatenachsen. Auch können Volumenänderungen gemessen 10 werden. Der Grenzpunkt mit diesen neuen Verfahren ist die Genauigkeit der Scanner verwendet, um das Testobjekt zu erfassen. Keine der Änderungen in der Genauigkeit der Referenz Scanner kann in Veränderungen des Testobjekts oder Scanfehler unterteilt werden. Scan-Genauigkeit ist oft ein Wert vom Hersteller angegebensteller abgeleitet vom Scannen klein, kalibriert 11 Objekte. Diese minimale Scan-Fehler ist anders, wenn das Scannen von großen Objekten wie ein Zahnbogen. Genauigkeit aus Richtigkeit und Präzision. Richtigkeit ist die Abweichung des gescannten Objekts von seiner realen Geometrie. Präzision ist die Abweichung zwischen wiederholten Scans (ISO 5725-1). In dieser Studie, eine neue optische Referenz Scanner, basierend auf der Fokusvariation Scanning-Technik wurde eingeführt, um Proben von Einzelzahn mit höchster Genauigkeit scannen bis zur vollen Bogen-Modelle. Diese Referenz-Scanner wurde als Basis für mehrere Studien, Vergleich Zahnabdruckgenauigkeit von konventionellen und digitalen Techniken 12-14 und für konkrete Projekte zur Okklusion und Abrieb von Dentalmaterialien. Das Ziel dieser Studie war es, grundlegende Informationen über die Genauigkeit der Referenz Scanner und einige Möglichkeiten bieten, dieses Gerät im Bereich der zahnmedizinischen Forschung zu verwenden.

<table border="0" cellpadding="0" cellspacing="0" width="669">
	<tbody>
		<tr>
			<td>Reference model</td>
			<td></td>
			<td></td>
			<td>individual non-precious metal model, derived from a patient impression</td>
		</tr>
		<tr>
			<td>Araldit repair</td>
			<td>Huntsmen Advanced Material, Basel, Switzerland</td>
			<td></td>
			<td>used for making the base of the reference model</td>
		</tr>
		<tr>
			<td>CamBase</td>
			<td>Dentona, Dortmund, Germany</td>
			<td></td>
			<td>Type IV dental ston for pouring conventional impressions</td>
		</tr>
		<tr>
			<td>Identium</td>
			<td>Kettenbach, Eschenburg, Germany</td>
			<td></td>
			<td>Vinylsiloxanether impression material for conventional impression</td>
		</tr>
		<tr>
			<td>inEOS model holder</td>
			<td>Sirona Dental Systems, Bensheim, Germany</td>
			<td></td>
			<td>used for fixing stone models at the reference scanner</td>
		</tr>
		<tr>
			<td>Accutrans</td>
			<td>Coltene Whaledent, Altst&#228;tten, Switzerland</td>
			<td></td>
			<td>used for making the base of thestone models</td>
		</tr>
		<tr>
			<td>President putty</td>
			<td>Coltene Whaledent, Altst&#228;tten, Switzerland</td>
			<td></td>
			<td>mix with accutrans for betterstability of the base</td>
		</tr>
		<tr>
			<td>Alicona Infinite Focus</td>
			<td>Alicona Imaging, Graz, Austria</td>
			<td></td>
			<td>Reference scanner&#160;</td>
		</tr>
	</tbody>
</table>

accuracy in dental medicine, a new way to measure trueness and precision

Bezugs Scanner sind in der Zahnmedizin verwendet, um eine Menge von Verfahren zu überprüfen. Das Hauptinteresse ist es, Methoden zu überprüfen Eindruck, da sie als Basis für Zahnersatz dienen. Die Strombegrenzung von vielen Referenz Scanner ist die mangelnde Genauigkeit Scannen von großen Objekten wie volle Zahnbögen oder die begrenzte Möglichkeit, detaillierte Zahnoberflächen zu beurteilen. Ein neuer Referenz Scanner, basierend auf Fokusvariation Scanning-Technik wurde im Hinblick auf höchste lokale und allgemeine Genauigkeit ausgewertet. Eine spezifische Scan-Protokoll wurde getestet, um ursprüngliche Zahnoberfläche aus Zahnabdrücke scannen. Auch wurden verschiedene Modellmaterialien überprüft. Die Ergebnisse zeigten eine hohe Scan-Genauigkeit der Referenzscanner mit einer mittleren Abweichung von 5,3 ± 1,1 um für Richtigkeit und 1,6 ± 0,6 um für Präzision bei Vollbogen-Scans. Aktuelle Zahnabdruckverfahren zeigten viel höhere Abweichungen (Richtigkeit: 20,4 ± 2,2 um, Präzision: 12,5 ± 2,5 um) than die interne Lesegenauigkeit des Referenz Scanner. Kleinere Objekte wie einzelne Zahnoberfläche kann mit einer noch höheren Genauigkeit gescannt werden, sodass das System erosive und abrasive Zahnoberfläche Verlust zu beurteilen. Die Referenz Scanner kann verwendet werden, um Unterschiede für viele zahnForschungsFeldern zu messen. Die verschiedenen Vergrößerungsstufen kombiniert mit einer hohen lokalen und allgemeinen Genauigkeit können Änderungen einzelner Zähne oder Zahnersatz bis zur vollen Bogen Veränderungen zu beurteilen.

Fig. 16A zeigt die Abtastung einer Gipsprobe. Um eine optimale Scan-Parameter überprüfen, steuern die Wiederholbarkeit für das Material. Ein Teil der Probe wird mit unterschiedlichem Kontrast-und Helligkeitseinstellungen gescannt und die Wiederholbarkeit wird nach jedem Scan überprüft, um die optimalen Scaneinstellungen finden. Metalloberflächen zeigen die besten Ergebnisse mit einem geringeren Kontrast 1.0 und Gips-oder Kunststoffmaterialien mit einem höheren Kontrast. 16B zeigt...

Watch this Scientific Journal Video about Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision at JoVE.com

Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision

Genauigkeit ist eine wichtige Forderung in der Zahnmedizin. Um die Genauigkeit zu überprüfen, werden Referenz Scanner benötigt. Dieser Artikel stellt eine neue Referenz-Scanner mit einer eingestellten Scan-Methode, um eine breite Vielzahl von zahnärztlichen Morphologien mit hoher Richtigkeit und Präzision zu erwerben.

Genauigkeit in Zahnmedizin, einen neuen Weg zu Richtigkeit und Präzision messen

Reference scanners are used in dental medicine to verify a lot of procedures. The main interest is to verify impression methods as they serve as a base ...

accuracy-dental-medicine-new-way-to-measure-trueness

Research

JoVE Journal

Medicine

13.3K Aufrufe.  University of Zürich.  Genauigkeit ist eine wichtige Forderung in der Zahnmedizin. Um die Genauigkeit zu überprüfen, werden Referenz Scanner benötigt. Dieser Artikel stellt eine neue Referenz-Scanner mit einer eingestellten Scan-Methode, um eine breite Vielzahl von zahnärztlichen Morphologien mit hoher Richtigkeit und Präzision zu erwerben. 

Serie: Accuracy in Dental Medicine, A New Way to Measure Trueness and Precision

Technique to Collect Fungiform (Taste) Papillae from Human Tongue

The sense of taste is critical for human life. It informs the body about the quality of food that will be potentially ingested and stimulates metabolic processes that prepare the alimentary canal for digestion. Steady progress is being made towards understanding the early biochemical and molecular events underlying taste transduction (for a review, Breslin and Spector, 20081). However, progress to date has largely resulted from animal models. Yet, since marked differences in receptor specificity and receptor density vary among species, human taste transduction will only be understood by using human taste tissue. Here we describe a biopsy technique to collect human fungiform papillae, visible as rounded pink anterior structures, about 0.5 mm in diameter that contain taste buds. These biopsied papillae are used for several purposes including the isolation of viable taste bud cells, in situ hybridization, immunohistochemistry and, through techniques of molecular biology, the identification of taste-specific novel proteins.

Technique to Collect Fungiform Taste Papillae from Human Tongue

Knowledge of molecular mechanisms underlying gustatory transduction has recently enjoyed significant advances, largely due to using animal models. However, the wide diversity in taste sensitivity and specificity among mammals warrants studies in human tissue. We describe a biopsy technique to collect living taste cells from the papillae on human tongue.

Technik zu pilzförmigen (Taste) Papillen aus menschlichen Zunge sammeln

The sense of taste is critical for human life. It informs the body about the quality of food that will be potentially ingested and stimulates metabolic ...

Forschung

Medizin

Construction of Vapor Chambers Used to Expose Mice to Alcohol During the Equivalent of all Three Trimesters of Human Development

Exposure to alcohol during development can result in a constellation of morphological and behavioral abnormalities that are collectively known as Fetal Alcohol Spectrum Disorders (FASDs). At the most severe end of the spectrum is Fetal Alcohol Syndrome (FAS), characterized by growth retardation, craniofacial dysmorphology, and neurobehavioral deficits. Studies with animal models, including rodents, have elucidated many molecular and cellular mechanisms involved in the pathophysiology of FASDs. Ethanol administration to pregnant rodents has been used to model human exposure during the first and second trimesters of pregnancy. Third trimester ethanol consumption in humans has been modeled using neonatal rodents. However, few rodent studies have characterized the effect of ethanol exposure during the equivalent to all three trimesters of human pregnancy, a pattern of exposure that is common in pregnant women. Here, we show how to build vapor chambers from readily obtainable materials that can each accommodate up to six standard mouse cages. We describe a vapor chamber paradigm that can be used to model exposure to ethanol, with minimal handling, during all three trimesters. Our studies demonstrate that pregnant dams developed significant metabolic tolerance to ethanol. However, neonatal mice did not develop metabolic tolerance and the number of fetuses, fetus weight, placenta weight, number of pups/litter, number of dead pups/litter, and pup weight were not significantly affected by ethanol exposure. An important advantage of this paradigm is its applicability to studies with genetically-modified mice. Additionally, this paradigm minimizes handling of animals, a major confound in fetal alcohol research.

We demonstrate the construction of alcohol vapor chambers using readily available materials that simultaneously house 6 mouse cages. We further describe their use in a mouse model of fetal alcohol exposure equivalent to all 3&#160;trimesters of human pregnancy. This paradigm exposes animals during gestation and postnatal days 1-12.

Bau von Dampfkammern verwendet, um Mäuse zu Alkohol Expose Während der Equivalent aller drei Trimester der Human Development

Exposure to alcohol during development can result in a constellation of morphological and behavioral abnormalities that are collectively known as Fetal ...

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. Despite the discovery of key regulators of uterine contractility, this process is still not fully understood. Transgenic mice provide an ideal model in which to study parturition. Previously, the only method to study uterine contractility in the mouse was ex vivo isometric tension recordings, which are suboptimal for several reasons. The uterus must be removed from its physiological environment, a limited time course of investigation is possible, and the mice must be sacrificed. The recent development of radiometric telemetry has allowed for longitudinal, real-time measurements of in vivo intrauterine pressure in mice. Here, the implantation of an intrauterine telemeter to measure pressure changes in the mouse uterus from mid-pregnancy until delivery is described. By comparing differences in pressures between wild type and transgenic mice, the physiological impact of a gene of interest can be elucidated. This technique should expedite the development of therapeutics used to treat myometrial disorders during pregnancy, including preterm labor.

Intrauterine Telemetry to Measure Mouse Contractile Pressure In Vivo

This manuscript provides a protocol for implanting telemeters in the mouse for the purpose of measuring intrauterine pressures during pregnancy.

Intrauterine Telemetrie zur Maus Kontraktionsdruck messen<em&gt; In-vivo-</em

A complex integration of molecular and electrical signals is needed to transform a quiescent uterus into a contractile organ at the end of pregnancy. ...

Studying Pancreatic Cancer Stem Cell Characteristics for Developing New Treatment Strategies

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor initiation, metastasis and resistance to radio- and chemotherapy. Here we describe a specific methodology for culturing primary human pancreatic CSCs as tumor spheres in anchorage-independent conditions. Cells are grown in serum-free, non-adherent conditions in order to enrich for CSCs while their more differentiated progenies do not survive and proliferate during the initial phase following seeding of single cells. This assay can be used to estimate the percentage of CSCs present in a population of tumor cells. Both size (which can range from 35 to 250 micrometers) and number of tumor spheres formed represents CSC activity harbored in either bulk populations of cultured cancer cells or freshly harvested and digested tumors 1,2. Using this assay, we recently found that metformin selectively ablates pancreatic CSCs; a finding that was subsequently further corroborated by demonstrating diminished expression of pluripotency-associated genes/surface markers and reduced in vivo tumorigenicity of metformin-treated cells. As the final step for preclinical development we treated mice bearing established tumors with metformin and found significantly prolonged survival. Clinical studies testing the use of metformin in patients with PDAC are currently underway (e.g., NCT01210911, NCT01167738, and NCT01488552). Mechanistically, we found that metformin induces a fatal energy crisis in CSCs by enhancing reactive oxygen species (ROS) production and reducing mitochondrial transmembrane potential. In contrast, non-CSCs were not eliminated by metformin treatment, but rather underwent reversible cell cycle arrest. Therefore, our study serves as a successful example for the potential of in vitro sphere formation as a screening tool to identify compounds that potentially target CSCs, but this technique will require further in vitro and in vivo validation to eliminate false discoveries.

Pancreatic cancer stem cells (CSCs) can be expanded in vitro using the anchorage-independent sphere culture technique, which represents a powerful tool to study CSC biology and can serve as the first step to develop novel CSC-targeting therapies. Here the methodology for expanding, analyzing and targeting of pancreatic CSCs is provided.

Studieren Bauchspeicheldrüsenkrebs Stammzelleigenschaften für die Entwicklung neuer Behandlungsstrategien

Pancreatic ductal adenocarcinoma (PDAC) contains a subset of exclusively tumorigenic cancer stem cells (CSCs) which have been shown to drive tumor ...

Boldness, Aggression, and Shoaling Assays for Zebrafish Behavioral Syndromes

A behavioral syndrome exists when specific behaviors interact under different contexts. Zebrafish have been test subjects in recent studies and it is important to standardize protocols to ensure proper analyses and interpretations. In our previous studies, we have measured boldness by monitoring a series of behaviors (time near surface, latency in transitions, number of transitions, and darts) in a 1.5 L trapezoidal tank. Likewise, we quantified aggression by observing bites, lateral displays, darts, and time near an inclined mirror in a rectangular 19 L tank. By dividing a 76 L tank into thirds, we also examined shoaling preferences. The shoaling assay is a highly customizable assay and can be tailored for specific hypotheses. However, protocols for this assay also must be standardized, yet flexible enough for customization. In previous studies, end chambers were either empty, contained 5 or 10 zebrafish, or 5 pearl danios (D. albolineatus). In the following manuscript, we present a detailed protocol and representative data that accompany successful applications of the protocol, which will allow for replication of behavioral syndrome experiments.

This manuscript describes the setup, implementation, and analysis of boldness, aggression, and shoaling in zebrafish and testing for the presence of a behavioral syndrome. A standardized approach for behavioral quantification will allow for easier comparison across studies. Modifications to this protocol are possible as each assay can be run individually.

Mut, Aggression, und Shoaling Assays für Zebrabärblinge Behavioral Syndromes

A behavioral syndrome exists when specific behaviors interact under different contexts. Zebrafish have been test subjects in recent studies and it is ...

Open Tracheostomy Gastric Acid Aspiration Murine Model of Acute Lung Injury Results in Maximal Acute Nonlethal Lung Injury

Acid pneumonitis is a major cause of sterile acute lung injury (ALI) in humans. Acid pneumonitis spans the clinical spectrum from asymptomatic to acute respiratory distress syndrome (ARDS), characterized by neutrophilic alveolitis, and injury to both alveolar epithelium and vascular endothelium. Clinically, ARDS is defined by acute onset of hypoxemia, bilateral patchy pulmonary infiltrates and non-cardiogenic pulmonary edema. Human studies have provided us with valuable information about the physiological and inflammatory changes in the lung caused by ARDS, which has led to various hypotheses about the underling mechanisms. Unfortunately, difficulties determining the etiology of ARDS, as well as a wide range of pathophysiology have resulted in a lack of critical information that could be useful in developing therapeutic strategies.
Translational animal models are valuable when their pathogenesis and pathophysiology accurately reproduce a concept proven in both in vitro and clinical settings. Although large animal models (e.g., sheep) share characteristics of the anatomy of human trachea-bronchial tree, murine models provide a host of other advantages including: low cost; short reproductive cycle lending itself to greater data acquisition; a well understood immunologic system; and a well characterized genome leading to the availability of a variety of gene deletion and transgenic strains. A robust model of low pH induced ARDS requires a murine ALI that targets mainly the alveolar epithelium, secondarily the vascular endothelium, as well as the small airways leading to the alveoli. Furthermore, a reproducible injury with wide differences between different injurious and non-injurious insults is important.
The murine gastric acid aspiration model presented here using hydrochloric acid employs an open tracheostomy and recreates a pathogenic scenario that reproduces the low pH pneumonitis injury in humans. Additionally, this model can be used to examine interaction of a low pH insult with other pulmonary injurious entities (e.g., food particles, pathogenic bacteria).

This protocol induces acute lung injury in a mouse that has close fidelity to the pathogenesis of acid pneumonitis observed in humans. We generate a maximal acute nonlethal low pH lung injury and account for differences in rodent-human anatomic respiratory structure using an open tracheostomy coupled with circumferential pressure release.

Offene Tracheotomie Magensäure Aspiration Mausmodell der akuten Lungenschädigung Ergebnisse in Maximal Akute nonlethal Lung Injury

Acid pneumonitis is a major cause of sterile acute lung injury (ALI) in humans. Acid pneumonitis spans the clinical spectrum from asymptomatic to acute ...

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic responses to acute exercise are predominantly influenced by the duration and intensity of the exercise regimen. As exercise is increasingly thought of as a therapeutic treatment and/or diagnostic tool, it is important that standardizable methodologies be utilized to understand the variability and to increase the reproducibility of exercise outputs and measurements of responses to such regimens. To that end, we describe two different cycling exercise regimens that yield different physiologic outputs. In a maximal exercise test, exercise intensity is continually increased with a greater workload resulting in an increasing cardiopulmonary and metabolic response (heart rate, stroke volume, ventilation, oxygen consumption and carbon dioxide production). In contrast, during endurance exercise tests, the demand is increased from that at rest, but is raised to a fixed submaximal exercise intensity resulting in a cardiopulmonary and metabolic response that typically plateaus. Along with the protocols, we provide suggestions on measuring physiologic outputs that include, but are not limited to, heart rate, slow and forced vital capacity, gas exchange metrics, and blood pressure to enable the comparison of exercise outputs between studies. Biospecimens can then be sampled to assess cellular, protein, and/or gene expression responses. Overall, this approach can be easily adapted into both short- and long-term effects of two distinct exercise regimens.

To assess the influence of exercise intensity on physiologic and biologic responses, two different exercise testing protocols were utilized. Methods outlining exercise testing on a cycle ergometer as an incremental maximal oxygen consumption test and endurance, steady state submaximal endurance test are described.

Durchführung von Tests zur Messung der physiologischer und biologischen Reaktionen auf akute Übung beim Menschen Submaximalen und maximalen Ausdauerbelastungen

Regular physical activity has a positive effect on human health, but the mechanisms controlling these effects remain unclear. The physiologic and biologic ...

Precision Implementation of Minimal Erythema Dose (MED) Testing to Assess Individual Variation in Human Inflammatory Response

Minimal erythema dose (MED) testing is frequently used in clinical settings for determining the smallest amount of ultraviolet (UV) irradiation necessary to produce erythema (inflammatory reddening) on the surface of the skin. In this context, the MED is regarded as a key factor in determining starting doses for UV phototherapy for common skin conditions such as psoriasis and eczema. In research settings, MED testing also has potential to be a powerful tool for assessing within- and between-persons variation in inflammatory responses. However, MED testing has not been widely adopted for use in research settings, likely owing to a lack of published guidelines, which is a barrier to obtaining reproducible results from this assay. Also, protocols and equipment for establishing MED vary widely, making it difficult to compare results across laboratories. Here, we describe a precise and reproducible method to induce and measure superficial erythema using newly designed protocols and methods that can easily be adapted to other equipment and laboratory environments. The method described here includes detail on procedures that will allow extrapolation of a standardized dosage schedule to other equipment so that this protocol can be adapted to any UV radiation source.

Precision Implementation of Minimal Erythema Dose MED Testing to Assess Individual Variation in Human Inflammatory Response

Minimal erythema dose (MED) testing is used to establish dosage schedules for ultraviolet radiation phototherapy. It can assess individual variation in inflammatory response but lacks methodology for achieving reproducible results. Here, we present a precision implementation of MED and demonstrate its ability to capture individual variation in inflammatory response.

Präzisionsimplementierung von Minimal Erythema Dose (MED)-Tests zur Beurteilung individueller Variationen in der menschlichen Entzündlichen Reaktion

Minimal erythema dose (MED) testing is frequently used in clinical settings for determining the smallest amount of ultraviolet (UV) irradiation necessary ...

Murine Precision-Cut Liver Slices as an Ex Vivo Model of Liver Biology

Understanding the mechanisms of liver injury, hepatic fibrosis, and cirrhosis that underlie chronic liver diseases (i.e., viral hepatitis, non-alcoholic fatty liver disease, metabolic liver disease, and liver cancer) requires experimental manipulation of animal models and in vitro cell cultures. Both techniques have limitations, such as the requirement of large numbers of animals for in vivo manipulation. However, in vitro cell cultures do not reproduce the structure and function of the multicellular hepatic environment. The use of precision-cut liver slices is a technique in which uniform slices of viable mouse liver are maintained in laboratory tissue culture for experimental manipulation. This technique occupies an experimental niche that exists between animal studies and in vitro cell culture methods. The presented protocol describes a straightforward and reliable method to isolate and culture precision-cut liver slices from mice. As an application of this technique, ex vivo liver slices are treated with bile acids to simulate cholestatic liver injury and ultimately assess the mechanisms of hepatic fibrogenesis.

This protocol provides a simple and reliable method for the production of viable precision-cut liver slices from mice. The ex vivo tissue samples can be maintained under laboratory tissue culture conditions for multiple days, providing a flexible model to examine liver pathobiology.

Murine Präzisionsgeschnittene Leberscheiben als Ex-Vivo-Modell der Leberbiologie

Understanding the mechanisms of liver injury, hepatic fibrosis, and cirrhosis that underlie chronic liver diseases (i.e., viral hepatitis, non-alcoholic ...

Intraoperative Assessment of Resection Margins in Oral Cavity Cancer: This is the Way

The goal of head and neck oncological surgery is complete tumor resection with adequate resection margins while preserving acceptable function and appearance. For oral cavity squamous cell carcinoma (OCSCC), different studies showed that only 15%-26% of all resections are adequate. A major reason for the low number of adequate resections is the lack of information during surgery; the margin status is only available after the final histopathologic assessment, days after surgery.
The surgeons and pathologists at the Erasmus MC University Medical Center in Rotterdam started the implementation of specimen-driven intraoperative assessment of resection margins (IOARM) in 2013, which became the standard of care in 2015. This method enables the surgeon to turn an inadequate resection into an adequate resection by performing an additional resection during the initial surgery. Intraoperative assessment is supported by a relocation method procedure that allows accurate identification of inadequate margins (found on the specimen) in the wound bed.
The implementation of this protocol resulted in an improvement of adequate resections from 15%-40%. However, the specimen-driven IOARM is not widely adopted because grossing fresh tissue is counter-intuitive for pathologists. The fear exists that grossing fresh tissue will deteriorate the anatomical orientation, shape, and size of the specimen and therefore will affect the final histopathologic assessment. These possible negative effects are countered by the described protocol. Here, the protocol for specimen-driven IOARM is presented in detail, as performed at the institute.

The goal of this protocol is to provide a clear overview of specimen-driven intraoperative assessment of resection margins. It is encouraged to implement this protocol to improve patient care at other institutes.