The authors thank the dental technician Nicola Lanfranconi for producing the master reference model and the Alicona Company for their ongoing support with improving the scan software.

1. عينة إعداد / قاعدة <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> تطبيق قاعدة مسطحة حول العينة. وضع العينة على الطاولة المسح. توجيه سطح الإطباق على المستوى الأفقي (الشكل 1). </li></ol> 2. تحليل البرمجيات <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> بدء تشغيل البرنامج ثم مختبر وحدة القياس (الشكل 2) </li><li style=";text-align:right;direction:rtl"> وضع العينة في وسط الجدول المسح. </li><li style=";text-align:right;direction:rtl"> اختيار العدسة التكبير الصحيح. للالأجسام الكبيرة، مثل بالاشعة قوس كامل، استخدم الهدف 5X. </li><li style=";text-align:right;direction:rtl"> نقل البصرية المسح الضوئي باستخدام الماوس 3D حتى يتم عرض سطح العينة على نافذة عرض لايف (الشكل 3). </li><li style=";text-align:right;direction:rtl"> استخدام جهاز التحكم استشعار لضبط التعرض والتباين لتحقيق المعلمات المسح الضوئي الأمثل. للأسطح المعادن، استخدم التعرض ما بين 400 و 800 μsec والتناقض بين 0.3 و 0.8 (الشكل 4). </li><li style=";text-align:right;direction:rtl"> والتحقق من جودة الصورة عن طريق التحقق من زر&quot;مشاهدة جودة الصورة في المعاينة المباشرة&quot;. </li><li style=";text-align:right;direction:rtl"> تعيين المعلمات الصحيحة في قسم &quot;تحكم القياس&quot;. نوع القياس هو &quot;مجموعة بيانات 3D&quot;؛ ImageField النوع هو &quot;العام ImageField&quot; (الشكل 5). </li><li style=";text-align:right;direction:rtl"> انقر على &quot;ImageField جديد&quot;. </li><li style=";text-align:right;direction:rtl"> تحديد حجم المسح الضوئي. البرنامج يحتاج الإحداثيات إحاطة من حجم التدبير. <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> نقل العينة إلى مستوى أعلى وأدنى المسح والنقر على &quot;أضف الموقع&quot; في كل نقطة. يظهر &quot;Z المدى&quot; قيمة الارتفاع الفعلي لحجم المسح الضوئي (الشكل 6). </li><li style=";text-align:right;direction:rtl"> نقل العينة إلى boundings XY من حجم المسح الضوئي. انقر على &quot;أضف الموقع&quot; لتحديد X-المحور وأطوال Y-المحور. ويظهر البعد من حجم المسح الضوئي في &quot;المعلومات&quot; التبويب ويجب أن تتجاوز أبعاد العينة بمقدار 1 سم في المحور السيني والمحور Y. </li></ol></li><li style=";text-align:right;direction:rtl"> التحقق من &quot;النقاط&quot; الرقم. البرنامج قادر على مسح 100 مليون نقطة السطح في واحد &quot;ImageField&quot; المسح الضوئي. العدد الفعليمن نقطة تتجاوز هذا الحد. &quot;تهلك&quot; رقم نقطة قياس لمن قبل &quot;الاختزال الجانبي&quot; من حجم النقطة. <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> انقر على &quot;إعدادات متقدمة&quot; (الشكل 7). </li><li style=";text-align:right;direction:rtl"> نقل &quot;الجانبي الاختزال&quot; المنزلق إلى اليمين حتى يتم تقليل &quot;النقاط&quot; عدد أقل من 100 م (الشكل 7). الاختزال يقلل من قرار الجانبي للنقطة السطح، مما أدى إلى أكبر حجم بكسل الكائن الممسوحة ضوئيا. لضمان نتائج مسح الأمثل، يتم زيادة الدقة العمودية. </li></ol></li><li style=";text-align:right;direction:rtl"> انقر على &quot;ابدأ القياس&quot;. سيبدأ هذا &quot;وضع المعاينة&quot;. البرنامج ينفذ prescan مع أبعاد X و Y-المحور المحدد. </li><li style=";text-align:right;direction:rtl"> بعد الانتهاء من prescan، حدد المنطقة من الفائدة. وهذا يساعد على تقليل حجم الملف ووقت المسح (الشكل 8). </li><li style=";text-align:right;direction:rtl"> تحديد كافة أجزاء من prescan باستثناء عينة وحقلين حول قياس العينة، الذي يحتوي على قاعدة مسطحة (الشكل 9). </li><li style=";text-align:right;direction:rtl"> انقر على &quot;ابدأ&quot; لبدء المسح الضوئي. </li><li style=";text-align:right;direction:rtl"> السيطرة على المسح الضوئي في &quot;ImageViewer&quot; باستخدام الماوس واضغط على زر الماوس الأيسر (الشكل 10). </li><li style=";text-align:right;direction:rtl"> إغلاق النافذة وانقر على &quot;عرض الزائفة اللون فقط&quot;. </li><li style=";text-align:right;direction:rtl"> انقر على &quot;إعدادات&quot; و &quot;الزائفة تلوين&quot;، واختيار &quot;التكرار&quot;. </li><li style=";text-align:right;direction:rtl"> تعيين &quot;ماكس&quot;. نقدر لل0.2 وانقر على &quot;تطبيق النطاق&quot;. </li><li style=";text-align:right;direction:rtl"> السيطرة على التكرار، يجب أن يكون مساويا للمناطق مع نفس المنحدر والمادية. على وجه الخصوص، ينبغي للقاعدة حول العينة عرض التكرار متجانسة (الشكل 11). </li><li style=";text-align:right;direction:rtl"> انقر على &quot;قاعدة بيانات&quot; وحفظ المسح إلى المجلد المناسب. </li><li style=";text-align:right;direction:rtl"> تصدير المسح الضوئي لتنسيقات الملفات المختلفة، إذا لزم الأمر. انقر على &quot;File/Export/3D بيانات باسم / ....&quot; يمكن أن يكون مؤقتا البروتوكول في تلك المرحلة واصلت في وقت لاحق. </li></ol> 3. تحليل الفرق <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> استخدام &quot;3D-محرر&quot; لخفض بعيدا القاعدة. لن يتم استخدام هذا المجال للفرقالتحليل. </li><li style=";text-align:right;direction:rtl"> لمقارنة وتحليل بالاشعة اثنين، بدء تشغيل &quot;قياس الفرق&quot; البرمجيات (الشكل 12). </li><li style=";text-align:right;direction:rtl"> اختيار النموذج الثاني للمقارنة. </li><li style=";text-align:right;direction:rtl"> انقر على &quot;تلقائي الخام محاذاة&quot; لأداء المباراة الأولى من النماذج. </li><li style=";text-align:right;direction:rtl"> انقر على &quot;تعديل يدوي&quot; ومحاذاة النماذج مع الدورية وتتحرك حتى تكون في نفس الاتجاه (الشكل 13). </li><li style=";text-align:right;direction:rtl"> انقر على &quot;محاذاة تلقائي&quot; و &quot;تطبيق&quot; لبدء خوارزمية أفضل لائقا للنموذج مطابقة الأمثل. </li><li style=";text-align:right;direction:rtl"> انقر على &quot;الاختلافات&quot; لعرض خريطة اختلاف النموذجين المتطابقة. </li><li style=";text-align:right;direction:rtl"> تحديد نطاق اللون المناسب لعرض الانحرافات (الشكل 14). حفظ نمط الانحراف البصرية كما لقطة لتحليلها. </li></ol> انقر على &quot;الاحصائيات&quot; لعرض القيم الإحصائية للفروق. اختيار حجم الطبقة 1 ميكرون وحفظ بيانات الرسم البياني إلى ملف نصي للمقارنة إحصائية (الشكل 15).

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The authors declare that they have no competing financial interests or other conflicts of interest.

Accuracy is a basic demand in dental medicine. The reference scanner is capable of scanning small and large objects with high trueness and precision. With the optimal scanning method, even individual morphological detailed dental surfaces can be scanned with a high resolution and repeatability. With the different magnification levels of the scanner, macro and micro morphological structures can be acquired. It is possible to scan a variety of model materials.
The evaluation of the reference sca...

دقة هو مصلحة كبرى في العديد من المجالات في مجال طب الأسنان. استبدال الأنسجة الصلبة الأسنان يحتاج إلى بدلة المناسب بالضبط لضمان وظيفة مناسبة ومنع المزيد من تدمير ما تبقى من بنية الأسنان 1،2. أطقم الأسنان الجزئية الثابتة ومجموع بدلة حاسمة خاصة بالنسبة للتركيب الدقيق إلى دعم هياكل مثل الأسنان مستعدة أو يزرع 3. هذا هو السبب في أن هناك حاجة إلى استنساخ دقيق للغاية، وخاصة في مجال طب الأسنان والانطباعات سير العمل مختبر الأسنان. ومع ذلك، غيرها من مجالات علاج الأسنان أيضا الاستفادة من نتائج متري صحيح ودقيق، للتحقق من نجاح العلاج وتقييم استراتيجيات جديدة العلاج، مثل المادية وغير المادية تكبير الأنسجة، والتعرية والتآكل والرصد، وعلاجات اللثة، تقويم الأسنان والعلاجات 4،5. في العديد من هذه المجالات، وإجراءات التحقق من صحة القياسات الحالية هي المسافة الخطية مع الفرجار أو المجاهر 6،7. هذه المنهجياتالمواد المستنفدة للأوزون تقتصر على عدد قليل فقط نقاط القياس والمعلومات محدودة ثلاثي الأبعاد (3D) التغيرات في منطقة الاختبار. وتشمل أساليب قياس أحدث واسر البصرية أو التصوير الشعاعي لكامل سطح الاختبار 8،9 الكائن. هنا، يتم قياس السطح بأكمله أو وحدة التخزين وعرض ككائن 3D على شاشة الكمبيوتر. القياسات الخطية ممكنة، فضلا عن superimpositions نماذج من العصور مسح مختلفة. مع هذا التراكب، تقييم التغيرات السطحية في كل نقطة المسح هو ممكن. وهذا يتيح إمكانية رصد منطقة معينة أو عرض تشوهات في كل ثلاثة محاور تنسيق. أيضا، تغييرات الحجمي يمكن قياس 10. نقطة تحد مع هذه الأساليب الجديدة هو دقة الماسح الضوئي، وتستخدم لالتقاط الكائن الاختبار. ويمكن تقسيم أي من التغييرات داخل دقة الماسح الضوئي إشارة إلى التغييرات الكائن اختبار أو أخطاء المسح الضوئي. دقة المسح الضوئي وغالبا ما يكون قيمة معينة من قبل مانوالمستمدة من مسح facturer الصغيرة، والكائنات معايرة 11. هذا الحد الأدنى من الخطأ مسح يختلف عند مسح الأجسام الكبيرة مثل قوس الأسنان. يتكون دقة الصدق والدقة. الصدق هو انحراف للكائن الممسوحة ضوئيا من الهندسة الحقيقية. الدقة هي الانحراف بين بمسح المتكررة (ISO 5725-1). في هذه الدراسة، ماسح ضوئي الإشارة الضوئية الجديدة، استنادا إلى التركيز الاختلاف تقنية المسح الضوئي، وقدم لفحص عينات من الأسنان واحدة تصل إلى نماذج القوس الكامل مع أعلى دقة. وقد استخدم هذا الماسح الضوئي إشارة كقاعدة لعدة دراسات، مقارنة دقة الانطباع الأسنان من التقنيات التقليدية والرقمية 12-14 والفعلية للمشاريع المتعلقة إطباق الأسنان وتآكل مواد طب الأسنان. كان الهدف من هذه الدراسة هو توفير معلومات أساسية للدقة الماسح الضوئي المرجعية وبعض الإمكانيات لاستخدام هذا الجهاز في مجال أبحاث طب الأسنان.

<table><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&amp;auml;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&amp;auml;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&amp;nbsp;</td></tr></tbody></table>

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

وتستخدم الماسحات الضوئية الإشارة في طب الأسنان للتحقق الكثير من الإجراءات. الاهتمام الرئيسي هو للتحقق من أساليب الانطباع أنها بمثابة قاعدة لترميم الأسنان. الحد الحالي من العديد من الماسحات الضوئية المرجعية هو عدم وجود دقة المسح الضوئي الأجسام الكبيرة مثل الأقواس الأسنان الكاملة، أو إمكانية محدودة لتقييم أسطح الأسنان تفصيلا. والماسحة الضوئية مرجعية جديدة، تقوم على التركيز الاختلاف تقنية المسح الضوئي، وقد تم تقييم فيما يتعلق بأعلى دقة المحلية والعامة. تم اختبار بروتوكول المسح محددة لمسح سطح الأسنان الأصلية من الانطباعات الأسنان. أيضا، تم التحقق من المواد نموذج مختلف. أظهرت النتائج دقة المسح الضوئي عالية من الماسح الضوئي المرجعية مع انحراف متوسط ​​5.3 ± 1.1 ميكرومتر لالصدق و 1.6 ± 0.6 ميكرومتر من أجل الدقة في حالة بالاشعة القوس الكامل. أظهرت الأساليب الحالية الانطباع الأسنان أعلى من ذلك بكثير الانحرافات (الصدق: 20.4 ± 2.2 ميكرومتر، والدقة: 12.5 ± 2.5 ميكرومتر) رهان دقة المسح الضوئي الداخلية من الماسح الضوئي المرجعية. أصغر الكائنات مثل سطح الأسنان واحد يمكن مسحها مع دقة أعلى من ذلك، تمكين النظام من تقييم التآكل وجلخ فقدان سطح الأسنان. الماسح الضوئي مرجعية يمكن استخدامها لقياس الاختلافات لكثير من المجالات البحثية الأسنان. مستويات التكبير المختلفة جنبا إلى جنب مع دقة المحلية والعامة عالية يمكن استخدامها لتقييم التغيرات الأسنان واحد أو الترميم تصل إلى تغييرات القوس الكامل.

Figure 16A shows the scan of a gypsum specimen. To verify optimal scan parameters, control the repeatability for the material. A section of the specimen is scanned with different contrast and brightness settings and the repeatability is checked after each scan to find the optimal scan settings. Metal surfaces show the best results with a contrast lower 1.0 and gypsum or resin materials with a higher contrast. Figure 16B shows the repeatability without optimal scanning parameters after th...

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

Accuracy is a major demand in dental medicine. To verify accuracy, reference scanners are needed. This article presents a new reference scanner with an adjusted scanning method to acquire a broad variety of dental morphologies with high trueness and precision.

الدقة في طب الأسنان، طريقة جديدة لقياس الصدق والدقة

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 Views.  University of Zürich. Accuracy is a major demand in dental medicine. To verify accuracy, reference scanners are needed. This article presents a new reference scanner with an adjusted scanning method to acquire a broad variety of dental morphologies with high trueness and precision.

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

Shrinkage of Dental Composite in Simulated Cavity Measured with Digital Image Correlation

Polymerization shrinkage of dental resin composites can lead to restoration debonding or cracked tooth tissues in composite-restored teeth. In order to understand where and how shrinkage strain and stress develop in such restored teeth, Digital Image Correlation (DIC) was used to provide a comprehensive view of the displacement and strain distributions within model restorations that had undergone polymerization shrinkage.
Specimens with model cavities were made of cylindrical glass rods with both diameter and length being 10 mm. The dimensions of the mesial-occlusal-distal (MOD) cavity prepared in each specimen measured 3 mm and 2 mm in width and depth, respectively. After filling the cavity with resin composite, the surface under observation was sprayed with first a thin layer of white paint and then fine black charcoal powder to create high-contrast speckles. Pictures of that surface were then taken before curing and 5 min after. Finally, the two pictures were correlated using DIC software to calculate the displacement and strain distributions.
The resin composite shrunk vertically towards the bottom of the cavity, with the top center portion of the restoration having the largest downward displacement. At the same time, it shrunk horizontally towards its vertical midline. Shrinkage of the composite stretched the material in the vicinity of the &#8220;tooth-restoration&#8221; interface, resulting in cuspal deflections and high tensile strains around the restoration. Material close to the cavity walls or floor had direct strains mostly in the directions perpendicular to the interfaces. Summation of the two direct strain components showed a relatively uniform distribution around the restoration and its magnitude equaled approximately to the volumetric shrinkage strain of the material.

In order to understand the spatial development of polymerization shrinkage stress in dental resin-composite restorations, Digital Image Correlation was used to provide full-field displacement/strain measurement of restored model glass cavities by correlating images of the restoration taken before and after polymerization.

انكماش الأسنان مركب في تجويف مقلد قياس مع الارتباط الصور الرقمية

Polymerization shrinkage of dental resin composites can lead to restoration debonding or cracked tooth tissues in composite-restored teeth. In order to ...

Measuring the Complete-arch Distortion of an Optical Dental Impression

Digital workflows have actively been used to produce dental restorations or oral appliances since dentists started to make digital impressions by acquiring 3D images with an intraoral scanner. Because of the nature of scanning the oral cavity in the patient&#39;s mouth, the intraoral scanner is a handheld device with a small optical window, stitching together small data to complete the entire image. During the complete-arch impression procedure, a deformation of the impression body can occur and affect the fit of the restoration or appliance. In order to measure these distortions, a master specimen was designed and produced with a metal 3D printer. Designed reference geometries allow setting independent coordinate systems for each impression and measure x, y, and z displacements of the cylinder top circle center where the distortion of the impression can be evaluated. In order to evaluate the reliability of this method, the coordinate values of the cylinder are calculated and compared between the original computer-aided design (CAD) data and the reference data acquired with the industrial scanner. The coordinate differences between the two groups were mostly less than 50 &#181;m, but the deviations were high due to the tolerance of 3D printing in the z coordinates of the obliquely designed cylinder on the molar. However, since the printed model sets a new standard, it does not affect the results of the test evaluation. The reproducibility of the reference scanner is 11.0 &#177; 1.8 &#181;m. This test method can be used to identify and improve upon the intrinsic problems of an intraoral scanner or to establish a scanning strategy by measuring the degree of distortion at each part of the complete-arch digital impression.

Here, we present a protocol to measure the degree of distortion at each part of the compete-arch digital impression acquired from an intraoral scanner with 3D-printed metal phantom with standard geometries.

قياس تشويه القوس الكامل لمطباع الأسنان البصري

Digital workflows have actively been used to produce dental restorations or oral appliances since dentists started to make digital impressions by ...

Engineering

Digital Hybrid Model Preparation for Virtual Planning of Reconstructive Dentoalveolar Surgical Procedures

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial registration, and free-form surface modeling. Firstly cone-beam computed tomography datasets were reconstructed with a semi-automatic segmentation method. Alveolar bone and teeth are separated into different segments, allowing 3D morphology, and localization of periodontal intrabony defects to be assessed. The severity, extent, and morphology of acute and chronic alveolar ridge defects are validated concerning adjacent teeth. On virtual complex tissue models, positions of dental implants can be planned in 3D. Utilizing spatial registration of IOS and CBCT data and subsequent free-form surface modeling, realistic 3D hybrid models can be acquired, visualizing alveolar bone, teeth, and soft tissues. With the superimposition of IOS and CBCT soft tissue, thickness above the edentulous ridge can be assessed about the underlying bone dimensions; therefore, flap design and surgical flap management can be determined, and occasional complications may be avoided.

A workflow for creating three-dimensional (3D) virtual hybrid models has been designed based on cone-beam computed tomography dataset and intraoral optical scans utilizing radiographic image segmentation methods and free-form surface modeling. Digital models are used for the virtual planning of reconstructive dentoalveolar surgical procedures.

إعداد نموذج رقمي هجين للتخطيط الافتراضي للإجراءات الجراحية السنخية الترميمية

Virtual, hybrid three-dimensional (3D) model acquisition is presented in this article, utilizing the sequence of radiographic image segmentation, spatial ...

Dynamic Navigation for Dental Implant Placement

In modern implantology, the application of surgical navigation systems is becoming increasingly important. In addition to static surgical navigation methods, a guide-independent dynamic navigation implant placement procedure is becoming more widespread. The procedure is based on computer-guided dental implant placement utilizing optical control. This work aims to demonstrate the technical steps of a new dynamic computer-aided implant surgery (DCAIS)&#160;system (design, calibration, surgery) and check the accuracy of the results. Based on cone-beam computed tomography (CBCT) scans, the exact positions of implants are determined with dedicated software. The first step of the operation is the calibration of the navigation system, which can be performed in two ways: 1) based on CBCT images taken with a marker or 2) based on CBCT images without markers. Implants are inserted with the aid of real-time navigation according to the preoperative plans. The accuracy of the interventions can be evaluated based on postoperative CBCT images. The preoperative images containing the planned positions of the implants and postoperative CBCT images were compared based on the angulation (degree), platform, and apical deviation (mm) of the implants. To evaluate the data, we calculated the standard deviation (SD), mean, and standard error of the mean (SEM) of deviations within planned and performed implant positions. Differences between the two calibration methods were compared based on this data. Based on the interventions performed so far, the use of DCAIS allows for high-precision implant placement. A calibration system that does not require labeled CBCT recording allows for surgical intervention with similar accuracy as a system that uses labeling. The accuracy of the intervention can be improved by training.

Dynamic computer-aided implant surgery (DCAIS) is a controlled implant surgical placement method performed without a surgical template using optical control. The real-time intraoperative control of movement and position of the surgical device simplifies the procedure and gives more freedom to the surgeon, providing similar precision as static navigation methods.

التنقل الديناميكي لوضع زراعة الأسنان

In modern implantology, the application of surgical navigation systems is becoming increasingly important. In addition to static surgical navigation ...

A Standardized Approach to Extra-Oral and Intra-Oral Digital Photography

Contemporary dentistry mandates a more comprehensive and personalized analysis of each patient. Technological advances in digital photography have played vital roles in diagnostic accuracy, treatment planning, execution of therapies, and outcome evaluations, including esthetic enhancement. Digital photography also provides an excellent platform for patient education, communication, and co-management of cases with other healthcare providers. However, intra-oral photography often faces challenges such as inaccessibility of areas to be captured, different moveable vs. fixed tissues involved, contamination with saliva or blood, and differing illumination needs on various locations. Thus, a more standardized and systematic approach is proposed for intra- and extra-oral documentation via digital photography to overcome the existing technical challenges. The current work will outline the appropriate equipment specifications (camera bodies, macro lens, and flashes), positions and postures of the operator and patients, proper techniques of tissue retraction, the use of appropriate intra-oral mirrors, and the essential elements such as aperture settings (F-stop), ISO, shutter speed, and white balance. This article aims to provide all dental professionals with an approachable linear array of guidelines to produce simplified and standardized visual tools for more efficient and effective documentation.

The present protocol describes a method to capture intra- and extra-oral photographs for digital documentation in the clinical practice of dentistry. The protocol highlights all the critical components involved and the commonly utilized settings to capture dental photographs for clinical documentation.

نهج موحد للتصوير الرقمي خارج الفم وداخل الفم

Contemporary dentistry mandates a more comprehensive and personalized analysis of each patient. Technological advances in digital photography have played ...

Precision of In Vivo Quantitative Tooth Wear Measurement Using Intra-Oral Scans

Quantitative wear measurement is of increasing interest for measuring tooth wear progression. However, most research on quantitative wear measurement has focused on simulated wear or scanned gypsum casts. A 3D Wear Analysis (3DWA) protocol has been developed that analyzes tooth wear in vivo through intra-oral scanners available to dental clinicians. This study investigated the precision of the 3DWA protocol for measuring wear through maximum height loss (mm) and volume change (mm3). Observational prospective wear data from 55 patients were analyzed after 0-1-, 0-3-, and 0-5-year intervals to determine rates of wear, and convenience samples were chosen to test the protocol&#39;s precision on dentitions scanned twice in one sitting and its intra- and inter-rater precision on scans with 0-3- and 0-5-year intervals. Scans were made using intra-oral scanners (IOS) and superimposed using 3D measurement software. T-tests were performed to determine the structural and random error, and trimmed ranges were calculated to interpret the error. For protocol precision, the mean difference was 0.015 mm (-0.002; 0.032, p = 0.076) for height and -0.111 mm3 (-0.250; 0.023, p = 0.101) for volume. The duplicate measurement error was 0.062 mm for height and 0.268 mm3 for volume. The height measurements were precise enough to measure wear after intervals of 0-3 or 0-5 years; however, volume measurements were susceptible to procedural error and operator sensitivity. The 3DWA protocol is precise enough to adequately measure tooth height loss after intervals of a minimum of 3 years or in patients with severe wear progression, but it is not suited to measuring volumetric changes.

Precision of In Vivo Quantitative Tooth Wear Measurement Using Intra-Oral Scans

Quantitative wear measurement is a method of increasing importance in measuring tooth wear progression. We here describe a protocol, its precision, and its intra/inter-rater precision for the acquisition and superimposition of repeated in vivo scanned dentitions in patients with moderate to severe wear, reporting on both height and volume measurements.

دقة قياس تآكل الأسنان الكمي في الجسم الحي باستخدام المسح داخل الفم

Quantitative wear measurement is of increasing interest for measuring tooth wear progression. However, most research on quantitative wear measurement has ...

Dynamic Navigation in Endodontics: Guided Access Cavity Preparation by Means of a Miniaturized Navigation System

In the case of teeth with pulp canal calcification (PCC) and apical pathology or pulpitis, root canal treatment can be very challenging. PCC are common sequelae of dental trauma but can also occur with stimuli such as caries, bruxism, or after placing a restoration. In order to access the root canal as minimally invasive as possible in case of a necessary root canal treatment, dynamic navigation has recently been introduced in endodontics in addition to static navigation. The use of a dynamic navigation system (DNS) requires pre-operative cone-beam computed tomography (CBCT) imaging and a digital surface scan. If necessary, reference markers must be placed on the teeth before the CBCT scan; with some systems, these can also be planned and created digitally afterward. By means of a stereo camera connected to the planning software, the drill can now be coordinated with the help of reference markers and virtual planning. As a result, the position of the drill can be displayed on the monitor in real-time during preparation in different planes. In addition, the spatial displacement, the angular deviation, and the depth position are also displayed separately. The few commercially available DNS mostly consist of relatively large camera-marker-systems. Here, the DNS contains miniaturized components: a low-weight camera (97 g) mounted on the micromotor of the electric handpiece utilizing a manufacturer-specific connecting mechanism and a small marker (10 mm x 15 mm), which can be easily attached to an individually manufactured intraoral tray. For research purposes, a post-operative CBCT scan can be matched with the pre-operative one, and the volume of tooth structure removed can be calculated by the software. This work aims to present the technique of guided access cavity preparation by means of a miniaturized navigation system from imaging to clinical implementation.

Dynamic navigation systems (DNS) provide real-time visualization and guidance to the operator during endodontic access cavities preparation. The planning of the procedure requires three-dimensional imaging utilizing cone beam computed tomography and surface scans. After the export of the planning data to the DNS, access cavities can be prepared with minimal invasion.

الملاحة الديناميكية في علاج جذور الأسنان: إعداد تجويف الوصول الموجه عن طريق نظام ملاحة مصغر

In the case of teeth with pulp canal calcification (PCC) and apical pathology or pulpitis, root canal treatment can be very challenging. PCC are common ...

Guided Endodontics: Three-Dimensional Planning and Template-Aided Preparation of Endodontic Access Cavities

Pulp canal obliterations (PCO) are often a consequence of dental trauma, such as luxation injuries. Even though dentin apposition is a sign of vital pulp, pulpitis or apical periodontitis may develop in the long term. Root canal treatment of teeth with severe PCO and pulpal or periapical pathosis is challenging for general practitioners and even for well-equipped endodontic specialists. To ensure detection of the calcified root canal and avoid excessive loss of tooth structure or root perforation, static navigation using templates ("Guided Endodontics") was introduced a few years ago. The general workflow includes three-dimensional imaging using cone-beam computed tomography (CBCT), a digital surface scan, and superimposition of both in a planning software. This is followed by virtual planning of the access cavity and the design of a template that will guide the drill to the desired target point. To do this, a true-to-scale virtual image of the drill must be placed in a way that the tip of the drill reaches the orifice of the calcified root canal. Once the template has been fabricated using computer-aided design and computer-aided manufacturing (CAD/CAM) or a 3D printer, guided preparation of the access cavity can be performed clinically. For research purposes, a postoperative CBCT image can be used to quantify the accuracy of the access cavity performed. This work aims to present the technique of static guided endodontics from imaging to clinical implementation.

Guided endodontics describes a template-aided approach for access cavity preparation. The procedure requires cone-beam computed tomography and a surface scan to produce a template. An incorporated sleeve guides the drill to the target point. This allows the preparation of minimally invasive endodontic access cavities in calcified teeth.

علاج جذور الأسنان الموجه: التخطيط ثلاثي الأبعاد والتحضير بمساعدة القالب لتجاويف الوصول اللبية

Pulp canal obliterations (PCO) are often a consequence of dental trauma, such as luxation injuries. Even though dentin apposition is a sign of vital pulp, ...

تقييم حركة الأسنان الخلفية الفكية باستخدام التراكب الرقمي

Measuring Maxillary Posterior Tooth Movement: A Model Assessment using Palatal and Dental Superimposition

Since the introduction of Invisalign by Align Technology, Inc. in 1999, questions and debates have persisted regarding the precision of Invisalign (clear aligner) therapy, particularly when compared to the use of traditional fixed appliances. This becomes particularly significant in cases involving anteroposterior, vertical, and transverse corrections, where precise comparisons are of paramount importance. To address these inquiries, this study introduces a meticulously devised protocol, placing a primary emphasis on digitally superimposing the movement of maxillary posterior teeth to facilitate accurate analysis. The sample included 25 patients who had completed their first series of Invisalign (clear) aligners. Four maxillary digital models (pre-treatment, post-treatment, ClinCheck-initial, and final models) were digitally superimposed using the palate rugae and dentitions as stable references. A software combination was used for model superimposition and tooth segmentation. Transformation matrices then expressed the differences between the achieved and predicted tooth positions. Thresholds for clinically relevant differences were at &plusmn;0.25 mm for linear displacement and &plusmn;2&#176; for rotation. Differences were assessed using Hotelling's T-squared tests with Bonferroni correction. The mean differences in rotation (2.036&#176; &plusmn; 4.217&#176;) and torque (-2.913&#176; &plusmn; 3.263&#176;) were significant statistically and clinically, with p-values of 0.023 and 0.0003 respectively. De-rotation of premolars and torque control for all posterior teeth were less predictable. All mean differences for the linear measurements were statistically and clinically insignificant, except that the first molars seemed slightly (0.256 mm) more intruded than their predicted position. The clear aligner system appears to meet its prediction for most translational tooth movements and mesial-distal tipping in maxillary posterior teeth for non-extraction cases with mild to moderate malocclusions.

تسليط الضوء على المؤلف: تقييم حركة 3D للأسنان الخلفية الفكية في علاج التقويم الشفاف

This manuscript presents a comprehensive protocol to evaluate the three-dimensional (3D) movement of maxillary posterior teeth with clear aligners using digital model superimposition, an invaluable tool in orthodontics and dentofacial orthopedics.

قياس حركة الأسنان الخلفية الفكية: تقييم نموذجي باستخدام تراكب الحنك والأسنان

Since the introduction of Invisalign by Align Technology, Inc. in 1999, questions and debates have persisted regarding the precision of Invisalign (clear ...

الدقة في طب الأسنان، طريقة جديدة لقياس الصدق والدقة

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انكماش الأسنان مركب في تجويف مقلد قياس مع الارتباط الصور الرقمية

قياس تشويه القوس الكامل لمطباع الأسنان البصري

إعداد نموذج رقمي هجين للتخطيط الافتراضي للإجراءات الجراحية السنخية الترميمية

التنقل الديناميكي لوضع زراعة الأسنان

نهج موحد للتصوير الرقمي خارج الفم وداخل الفم

دقة قياس تآكل الأسنان الكمي في الجسم الحي باستخدام المسح داخل الفم

الملاحة الديناميكية في علاج جذور الأسنان: إعداد تجويف الوصول الموجه عن طريق نظام ملاحة مصغر

علاج جذور الأسنان الموجه: التخطيط ثلاثي الأبعاد والتحضير بمساعدة القالب لتجاويف الوصول اللبية

قياس حركة الأسنان الخلفية الفكية: تقييم نموذجي باستخدام تراكب الحنك والأسنان

قياس حركة الأسنان الخلفية الفكية: تقييم نموذجي باستخدام تراكب الحنك والأسنان