Name: dynamic navigation for dental implant placement
Uploaded: 2022-09-13T12:40:00
Description: Watch this Scientific Journal Video about Dynamic Navigation for Dental Implant Placement at JoVE.com

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Informed consent was obtained from every patient before surgery. After the interventions anonymized retrospective data was used in this study.
1. Steps in the traditional workflow of dynamic navigation systems using labeled clip calibration method (only for use on jawbone with teeth):
<ol>
	<li>Attach a radiopaque fixation clip to the teeth of the jawbone where the treatment is to be performed (maxilla/mandible) using a thermoplastic material.</li>
	<li>Make a CBCT examinati...

<ol>
	<li>Block, M. S., Emery, R. W., Cullum, D. R., Sheikh, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Implant+placement+is+more+accurate+using+dynamic+navigation.">Implant placement is more accurate using dynamic navigation.</a> Journal of Oral and Maxillofacial Surgery. 75 (7), 1377-1386 (2017).</li><li>Kaewsiri, D., Panmekiate, S., Subbalekha, K., Mattheos, N., Pimkhaokham, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+accuracy+of+static+vs.+dynamic+computer-assisted+implant+surgery+in+single+tooth+space:+A+randomized+controlled+trial.">The accuracy of static vs. dynamic computer-assisted implant surgery in single tooth space: A randomized controlled trial.</a> Clinical Oral Implants Research. 30 (6), 505-514 (2019).</li><li>Block, M. S., Emery, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Static+or+dynamic+navigation+for+implant+placement-choosing+the+method+of+guidance.">Static or dynamic navigation for implant placement-choosing the method of guidance.</a> Journal of Oral and Maxillofacial Surgery. 74 (2), 269-277 (2016).</li><li>Stefanelli, L. V., 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=Accuracy+of+a+novel+trace-registration+method+for+dynamic+navigation+surgery.">Accuracy of a novel trace-registration method for dynamic navigation surgery.</a> International Journal of Periodontics &amp; Restorative Dentistry. 40 (3), 427-435 (2020).</li><li>Mediavilla Guzman, A., Riad Deglow , E., Zubizarreta-Macho, A., Agustin-Panadero, R., Hernandez Montero, S. <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+computer-aided+dynamic+navigation+compared+to+computer-aided+static+navigation+for+dental+implant+placement:+An+in+vitro+study.">Accuracy of computer-aided dynamic navigation compared to computer-aided static navigation for dental implant placement: An in vitro study.</a> Journal of Clinical Medicine. 8 (12), 2123 (2019).</li><li>Sun, T. M., Lan, T. H., Pan, C. Y., Lee, H. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dental+implant+navigation+system+guide+the+surgery+future.">Dental implant navigation system guide the surgery future.</a> Kaohsiung Journal of Medical Sciences. 34 (1), 56-64 (2018).</li><li>Wu, Y., Wang, F., Fan, S., Chow, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Robotics+in+dental+implantology.">Robotics in dental implantology.</a> Oral and Maxillofacial Surgery Clinics of North America. 31 (3), 513-518 (2019).</li><li>Block, M. S., Emery, R. W., Lank, K., Ryan, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Implant+placement+accuracy+using+dynamic+navigation.">Implant placement accuracy using dynamic navigation.</a> International Journal of Oral &amp; Maxillofacial Implants. 32 (1), 92-99 (2017).</li><li>Panchal, N., Mahmood, L., Retana, A., Emery, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+navigation+for+dental+implant+surgery.">Dynamic navigation for dental implant surgery.</a> Oral and Maxillofacial Surgery Clinics of North America. 31 (4), 539-547 (2019).</li><li>Emery, R. W., Merritt, S. A., Lank, K., Gibbs, J. D. <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+dynamic+navigation+for+dental+implant+placement-model-based+evaluation.">Accuracy of dynamic navigation for dental implant placement-model-based evaluation.</a> Journal of Oral Implantology. 42 (5), 399-405 (2016).</li></ol>

In the labeled clip-used dynamic navigation implant placement system, the traditional workflow is done by clip calibration. There are three radiopaque metal spheres on the surface of the clip, which are clearly visible on the CBCT scan. In the case of the tracer calibration method, these metal spheres containing clips are neither necessary for the CBCT scanning nor system calibration. In cases with existing teeth, both the labeled and unlabelled clips can be used (two different calibration methods). The clip is attached ...

To increase the accuracy of dental implant placement and reduce the complications, a range of navigation techniques based on imaging studies have been developed. Preoperative imaging and special 3D implant planning software can be used to plan the exact position of the dental implant1,2.
The aim of implant surgery navigation is to accomplish a more anatomically precise placement of the dental implant to achieve the most ideal position, to reduce the risk of possible iatrogenic complications (nerve, vascular, bone, and sinus injuries). The navigated surgery decreases the invasiveness of the intervention (flapless surgery), which can lead to fewer complaints and faster recovery. The accurate implant placement is based on prior prosthetic planning (it is possible to perform the operation on the basis of a preoperative tooth installation) and the optimal implant positioning can help avoid bone grafting.
Nowadays, there are two types of computer-assisted implant (CAI) surgical placement navigation systems-static and dynamic navigation systems. Static navigation is a controlled implant placement method using a preplanned and prefabricated surgical template. Dynamic navigation is a preplanned computer-guided implant surgical placement method without a surgical template using optical control. The control procedure uses point cloud-based image registration to merge the virtual images with the real environment by applying 3D image overlay3.
DCAI systems make possible real-time, objectified instrument control within a GPS-like framework. Typically, they use optical tracking to detect and track the position of (optical) reference markers placed over the patient and the surgical instruments, and provide continuous visual feedback on the implant surgical placement process1,2.
The movement and position of the surgical instrument during surgery can be monitored live on a three-dimensional image on a monitor. During the procedure, the camera system allows continuous monitoring and comparison of the position of the patient&#39;s jawbone and the position of the surgical instrument.
There are two types of dynamic navigation systems: one is the passive system, in which case the registration devices (reference bases) reflect light emitted from the light source back to the stereo cameras; the other is the active system, where the registration devices emit light which is followed by stereo cameras4,5.
The next level of dynamic navigation systems uses servo motors to guide the surgeon&#39;s hand with tactile stimuli so that the device with robotic arms can determine the surgeon&#39;s movements or even replace them completely in the distant future4,5,6,7.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>DTX Implant Studio Software</td>
			<td>Nobel Biocare</td>
			<td>106182</td>
			<td>3D surgical planing software</td>
		</tr>
		<tr>
			<td>MeshLab</td>
			<td>ISTI - CNR research center</td>
			<td>2020.12</td>
			<td>3D mesh processing software</td>
		</tr>
		<tr>
			<td>Nobel Replace CC implant</td>
			<td>Nobel Biocare</td>
			<td>37285</td>
			<td>Implant</td>
		</tr>
		<tr>
			<td>X-Guide</td>
			<td>X-Nav - Nobel Biocare</td>
			<td>SN00001310</td>
			<td>dinamic navigation surgery system</td>
		</tr>
		<tr>
			<td>X-Guide - XClip</td>
			<td>X-Nav - Nobel Biocare</td>
			<td>XNVP008381</td>
			<td>3D navigation registration device</td>
		</tr>
		<tr>
			<td>X-Guide planing software</td>
			<td>X-Nav - Nobel Biocare</td>
			<td>XNVP008296</td>
			<td>3D surgical planing and operating software</td>
		</tr>
		<tr>
			<td>X-Mark probe</td>
			<td>X-Nav - Nobel Biocare</td>
			<td>XNVP008886</td>
			<td>3D navigation registration tool</td>
		</tr>
		<tr>
			<td>PaX-i3D Smart</td>
			<td>Vatech</td>
			<td></td>
			<td>CBCT</td>
		</tr>
		<tr>
			<td>Prolene 5.0</td>
			<td></td>
			<td></td>
			<td>5.0 monofilament, nonabsorbable polypropylene suture</td>
		</tr>
	</tbody>
</table>

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.

To use DCAIS correctly, the system must be calibrated. There are several calibration methods that can affect the accuracy of the implant placement. This study aimed to assess the potential impact of different calibration methods on the accuracy of DCAIS.
Based on the interventions performed so far, the use of DCAIS allows a high-precision implant placement. In our early studies, we compared 41 clip calibrated dynamic navigated implant placements with 17 tracer calibrated dynamic navigated impl...

Watch this Scientific Journal Video about Dynamic Navigation for Dental Implant Placement at JoVE.com

Dynamic Navigation for Dental Implant Placement

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.

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

Digital computerized implant systems enable real-time objectified instrument control within a GPS-like framework. The position of the instrument during surgery can be monitored live on a three-dimensional image on a monitor. This technique is precise, minimal invasive, does not need a surgical guide template, and easy to use in a small mouth.The planning and surgery can be performed on the same day, and modification is possible during the surgery. It is recommended to practice the method on a dental image before using it in a live situation. The procedure will be demonstrated by Tamas Huszar, an assistant professor from our department.Begin by attaching a radio pack fixation clip to the teeth of the jawbone at the treatment site with the help of a thermoplastic material. Make a cone beam computed tomography or CBCT examination of the patient with a labeled clip in the mouth. Plan the position of the implant according to the prosthetic architecture with the appropriate software.Register the headpiece by calibrating the handpiece chuck and the rotating marker disc, inserted into the handpiece. Then assemble the arm between the patient tracker and the labeled clip and calibrate it. To check the device calibration, fix the labeled clip holding the optical marker or tracker on the teeth on which jaw the implant placement will occur.Ensure to insert the clip in the same position registered on the preoperative CBCT. Then touch the clip's metal spheres with the pivot of the probe to calibrate the labeled clip. To perform the navigated implant placement and local anesthesia, measure the drill length and check the real-time visual accuracy.Determine the entry point of drilling and explore the operation site without the flap. Next, drill the bone with dynamic navigation control. After measuring the implant length, place the implant with the handpiece wearing the dynamic navigation system controlled tracker.Close the wound with 5/0 monofilament non-absorbable polypropylene suture or fix the prefabricated prosthetic work. Then acquire a control radiologic image. Perform CBCT on the patient without a clip in the mouth.Use appropriate software to plan the position of the implant according to the prosthetic architecture and calibrate the device as described previously. For calibrating the system without a labeled clip, transfer the plan of surgical placement of the implant into the navigation system software. Then select the workspace on the three-dimensional CT image of the navigation software.Fix the tracker on the teeth with an unlabeled clip, or, in the case of an edentulous jaw, fix a special tracker holding arm. Then select a minimum of three typical anatomical points on a 3D CT image of the navigation system. Identify the selected anatomical points in the mouth by touching them with a probe tool.Perform the refinement procedure on three to four areas by drawing on the surface of the anatomical structure with a probe. Under local anesthesia, place the implant with navigation and measure the drill length. Check the real-time visual accuracy of the tooth or at the surface of the bone before determining the drilling point and exploring the operation site without the flap.Drill the bone with dynamic navigation control. Measure the implant length before placing the implant with the handpiece wearing the dynamic navigation controlled tracker. Close the wound with a 5/0 monofilament non-absorbable polypropylene suture, or fix the prefabricated prosthetic work.Then, start control radiologic imaging. The data from the early study showed that there was no significant correlation between the platform and angular deviation in buccolingual and mesiodistal directions. When the planned and final position of the implants was compared, the clip calibration method proved more accurate compared to the tracer calibration method with no significant difference.It is essential to check the continuity of the calibration and the tracking of the procedure. The system will signal any malfunction. The procedure allows for a number of tracked dental treatments, such as root apex amputation, orthognathic surgery, endodontic procedures, or complicated wisdom tooth removal.

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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.

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

Oral Biofilm Formation on Different Materials for Dental Implants

Dental implants and their prosthetic components are prone to bacterial colonization and biofilm formation. The use of materials that provides low microbial adhesion may reduce the prevalence and progression of peri-implant diseases. In view of the oral environment complexity and oral biofilm heterogeneity, microscopy techniques are needed that can enable a biofilm analysis of the surfaces of teeth and dental materials. This article describes a series of protocols implemented for comparing oral biofilm formation on titanium and ceramic materials for prosthetic abutments, as well as the methods involved in oral biofilms analyses at the morphological and cellular levels. The in situ model to evaluate oral biofilm formation on titanium and zirconia materials for dental prosthesis abutments as described in this study provides a satisfactory preservation of the 48 h biofilm, thereby demonstrating methodological adequacy. Multiphoton microscopy allows the analysis of an area representative of the biofilm formed on the test materials. In addition, the use of fluorophores and the processing of the images using multiphoton microscopy allows the analysis of the bacterial viability in a very heterogeneous population of microorganisms. The preparation of biological specimens for electron microscopy promotes the structural preservation of biofilm, images with good resolution, and no artifacts.

Here, we present a protocol to evaluate oral biofilm formation on titanium and zirconia materials for dental prosthesis abutments, including the analysis of bacterial cells viability and morphological characteristics. An in situ model associated with powerful microscopy techniques is used for the oral biofilm analysis.

Dental implants and their prosthetic components are prone to bacterial colonization and biofilm formation. The use of materials that provides low ...

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or excision. Many of these nodules are identified and excised via minimally invasive thoracic surgery; however, subcentimeter and subsolid nodules are frequently difficult to identify intra-operatively. This can be mitigated by the use of electromagnetic transthoracic needle localization. This protocol delineates the step-by-step process of electromagnetic localization from the pre-operative period to the postoperative period and is an adaptation of the electromagnetically guided percutaneous biopsy previously described by Arias et al. Pre-operative steps include obtaining a same day CT followed by the generation of a three-dimensional virtual map of the lung. From this map, the target lesion(s) and an entry site are chosen. In the operating room, the virtual reconstruction of the lung is then calibrated with the patient and the electromagnetic navigation platform. The patient is then sedated, intubated, and placed in the lateral decubitus position. Using a sterile technique and visualization from multiple views, the needle is inserted into the chest wall at the prechosen skin entry site and driven down to the target lesion. Dye is then injected into the lesion and, then, continuously during needle withdrawal, creating a tract for visualization intra-operatively. This method has many potential benefits when compared to the CT-guided localization, including a decreased radiation exposure and decreased time between the dye injection and the surgery. Dye diffusion from the pathway occurs over time, thereby limiting intra-operative nodule identification. By decreasing the time to surgery, there is a decrease in wait time for the patient, and less time for dye diffusion to occur, resulting in an improvement in nodule localization. When compared to electromagnetic bronchoscopy, airway architecture is no longer a limitation as the target nodule is accessed via a transparenchymal approach. Details of this procedure are described in a step-by-step fashion.

Presented here is a protocol for lung nodule localization using dye marking via electromagnetically navigated transthoracic needle access. The technique described here can be accomplished in the peri-operative period to optimize nodule localization and to successful resection when performing minimally invasive thoracic surgery.

The increased use of chest computed tomography (CT) has led to an increased detection of pulmonary nodules requiring diagnostic evaluation and/or ...

In Vivo Mouse Model of Spinal Implant Infection

Spine implant infections portend poor outcomes as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. The purpose of this method is to describe a novel mouse model of spinal implant infection (SII) that was created to provide an inexpensive, rapid, and accurate in vivo tool to test potential therapeutics and treatment strategies for spinal implant infections.
In this method, we present a model of posterior-approach spinal surgery in which a stainless-steel k-wire is transfixed into the L4 spinous process of 12-week old C57BL/6J wild-type mice and inoculated with 1 x 103 CFU of a bioluminescent strain of Staphylococcus aureus Xen36 bacteria. Mice are then longitudinally imaged for bioluminescence in vivo on post-operative days 0, 1, 3, 5, 7, 10, 14, 18, 21, 25, 28, and 35. Bioluminescence imaging (BLI) signals from a standardized field of view are quantified to measure in vivo bacterial burden.
To quantify bacteria adhering to implants and peri-implant tissue, mice are euthanized and the implant and surrounding soft tissue are harvested. Bacteria are detached from the implant by sonication, cultured overnight and then colony forming units (CFUs) are counted. The results acquired from this method include longitudinal bacterial counts as measured by in vivo S. aureus bioluminescence (mean maximum flux) and CFU counts following euthanasia.
While prior animal models of instrumented spine infection have involved invasive, ex vivo tissue analysis, the mouse model of SII presented in this paper leverages noninvasive, real time in vivo optical imaging of bioluminescent bacteria to replace static tissue study. Applications of the model are broad and may include utilizing alternative bioluminescent bacterial strains, incorporating other types of genetically engineered mice to contemporaneously study host immune response, and evaluating current or investigating new diagnostic and therapeutic modalities such as antibiotics or implant coatings.

The protocol describes a novel in vivo mouse model of spinal implant infection where a stainless-steel k-wire implant is infected with bioluminescent Staphylococcus aureus Xen36. Bacterial burden is monitored longitudinally with bioluminescent imaging and confirmed with colony forming unit counts after euthanasia.

Spine implant infections portend poor outcomes as diagnosis is challenging and surgical eradication is at odds with mechanical spinal stability. The ...

Real-Time Dynamic Navigation System for the Precise Quad-Zygomatic Implant Placement in a Patient with a Severely Atrophic Maxilla

Zygomatic implants (ZIs) are an ideal way to address cases of a severely atrophic edentulous maxilla and maxilla defects because they replace extensive bone augmentation and shorten the treatment cycle. However, there are risks associated with the placement of ZIs, such as penetration of the orbital cavity or infra-temporal fossa. Furthermore, the placement of multiple ZIs makes this surgery risky and more difficult to perform. Potential intraoperative complications are extremely dangerous and may cause irreparable losses. Here, we describe a practical, feasible, and reproducible protocol for a real-time surgical navigation system for precisely placing quad-zygomatic implants in the severely atrophic maxilla of patients with residual bone that does not meet the requirements of conventional implants. Hundreds of patients have received ZIs at our department based on this protocol. The clinical outcomes have been satisfactory, the intraoperative and postoperative complications have been low, and the accuracy indicated by infusion of the designed image and postoperative three-dimensional image has been high. This method should be utilized during the entire surgical procedure to ensure ZI placement safety.

Here, we present a protocol to achieve precise quad-zygomatic implant placement in patients with severely atrophic maxilla using a real-time dynamic navigation system.

Zygomatic implants (ZIs) are an ideal way to address cases of a severely atrophic edentulous maxilla and maxilla defects because they replace extensive ...

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.

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 ...

A Retrograde Implantation Approach for Peritoneal Dialysis Catheter Placement in Mice

Murine models are employed to probe various aspects of peritoneal dialysis (PD), such as peritoneal inflammation and fibrosis. These events drive peritoneal membrane failure in humans, which remains an area of intense investigation due to its profound clinical implications in managing patients with end-stage kidney disease (ESKD). Despite the clinical importance of PD and its related complications, current experimental murine models suffer from key technical challenges that compromise the models&#39; performance. These include PD catheter migration and kinking and usually warrant earlier catheter removal. These limitations also drive the need for a greater number of animals to complete a study. Addressing these drawbacks, this study introduces technical improvements and surgical nuances to prevent commonly observed PD catheter complications in a murine model. Moreover, this modified model is validated by inducing peritoneal inflammation and fibrosis using lipopolysaccharide injections. In essence, this paper describes an improved method to create an experimental model of PD.

This article describes modifications of a procedure to implant a peritoneal dialysis catheter in a murine model to avoid major technical issues observed with the conventional techniques.

Murine models are employed to probe various aspects of peritoneal dialysis (PD), such as peritoneal inflammation and fibrosis. These events drive ...

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.

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, ...

Augmented Reality Navigation-Guided Core Decompression for Osteonecrosis of Femoral Head

Osteonecrosis of the femoral head (ONFH) is a common joint disease in young and middle-aged patients, which seriously burdens their lives and work. For early-stage ONFH, core decompression surgery is a classical and effective hip preservation therapy. In traditional procedures of core decompression with Kirschner wire, there are still many problems such as X-ray exposure, repeated puncture verification, and damage to normal bone tissue. The blindness of the puncture process and the inability to provide real-time visualization are crucial reasons for these problems.
To optimize this procedure, our team developed an intraoperative navigation system on the basis of augmented reality (AR) technology. This surgical system can intuitively display the anatomy of the surgical areas and render preoperative images and virtual needles to intraoperative video in real-time. With the guide of the navigation system, surgeons can accurately insert Kirschner wires into the targeted lesion area and minimize the collateral damage. We conducted 10 cases of core decompression surgery with this system. The efficiency of positioning and fluoroscopy is greatly improved compared to the traditional procedures, and the accuracy of puncture is also guaranteed.

Augmented reality technology was applied to core decompression for osteonecrosis of the femoral head to realize real-time visualization of this surgical procedure. This method can effectively improve the safety and precision of core decompression.

Osteonecrosis of the femoral head (ONFH) is a common joint disease in young and middle-aged patients, which seriously burdens their lives and work. For ...

Muscle Function Obtained with Motion Mode Ultrasound and Surface Electromyography during Core Endurance Exercise

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured between fascial borders at a given time point during an exercise. This selected time point produces a one-dimensional image resulting in real-time, live observation of anatomy. Ultrasound used during functional movement can be referred to as dynamic ultrasound; this is feasible and reliable with the use of a linear transducer, elastic belt, and foam block to secure consistent transducer placement. The lateral abdominal wall is commonly investigated using ultrasound due to the overlapping nature of the muscles. Surface electromyography (sEMG) can complement M-mode ultrasound imaging because it measures the electrical representation of muscle activation. There is minimal evidence using M-mode ultrasound and sEMG simultaneously during core exercise. Exercises that challenge the core musculature involve both isometric holds (e.g., side plank), as well as oscillatory extremity movements (e.g., dead bug). In this study, both instruments will be used simultaneously to measure core muscle function during exercise. Ultrasound measurements will be obtained using a linear transducer and ultrasound unit, and sEMG measurements will be acquired from a wireless sEMG system. To make comparisons between participants and exercises, normalization methods using static, exercise starting positions for both instruments will be used. An activation ratio will be used for ultrasound and calculated by dividing the contracted thickness (thickness during a time point of exercise) by the rested (starting position) thickness. Muscle thickness will be measured in centimeters from the superior inferior fascial border to inferior superior fascial border. These methods aim to offer an innovative and practical measurement of muscle function with M-mode ultrasound and sEMG during core endurance exercises.

This protocol uses motion mode ultrasound and surface electromyography simultaneously to measure muscle function of the core. Muscle thickness and activation of the local stabilizers (e.g., transverse abdominis, internal oblique) and global movers (e.g., external oblique) is achievable during specific time points of the side plank and dead bug exercises.

Motion mode (M-mode) ultrasound allows researchers and clinicians to measure the change of muscle thickness across time. Muscle thickness can be measured ...