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 examination of the patient with a labeled clip in the mouth (CBCT, FOV 8 cm x 11 cm, 12 mA, 95 kV).</li>
	<li>Plan the position of the implant according to the prosthetic architecture with the appropriate software.</li>
	<li>Calibrate the device (each step can be activated on display with the Play symbol).
	<ol>
		<li>Register the handpiece.
		<ol>
			<li>Calibrate handpiece chuck.</li>
			<li>Calibrate the rotating marker-disc inserted into the handpiece.</li>
			<li>Assemble the arm between the patient tracker and the labeled clip, and calibrate it.</li>
		</ol>
		</li>
	</ol>
	</li>
	<li>Check calibration by holding the tip of the measured drill to the surface of the labeled clip (Figure 1).
	<ol>
		<li>Fix the labeled clip holding the optical marker (tracker) on the teeth of the upper or lower jaw (on which jaw the implant placement occurs). Ensure to insert the clip in the same position registered on the preoperative CBCT.</li>
		<li>Calibrate the labeled clip by touching the metal spheres of the clip with the pivot of the probe.</li>
	</ol>
	</li>
	<li>Perform the navigated implant placement in local anesthesia, injecting 2 mL of articain (80 mg/2 mL articain/ampoule).
	<ol>
		<li>Measure the drill length (touching the drill to the go plate) (Figure 2).</li>
		<li>Check the real-time visual accuracy before drilling (touching the drill to any tooth surface and checking that it is in the same position on the monitor and the mouth).</li>
		<li>Determine the entry point of drilling. Explore the operation site without the flap.</li>
		<li>Drill the bone with dynamic navigation control (Figure 3, Figure 4, and Figure 5) .</li>
		<li>Measure the implant length (touching the implant to the go plate).</li>
		<li>Place the implant with the handpiece wearing the tracker controlled by the dynamic navigation system.</li>
		<li>Close the wound with 5.0 monofilament, nonabsorbable polypropylene suture, or fix the prefabricated prosthetic work.</li>
	</ol>
	</li>
	<li>Acquire control radiologic imaging (CBCT, FOV 8 cm x 11 cm, 12 mA, 95 kV).</li>
</ol>
2. Steps in the dynamic navigation systems using the tracer calibration method (not labeled method):
<ol>
	<li>Perform CBCT of the patient (without clip in the mouth).</li>
	<li>Plan the position of the implant according to the prosthetic architecture with the appropriate software.</li>
	<li>Calibrate the device as detailed in step 1.4.</li>
	<li>Calibrate the system without a labeled clip&#160;(not labeled method).
	<ol>
		<li>Transfer the plan of the implant surgical placement into the software of the used navigation system. Select the workspace on the 3D CT image of the navigation software.</li>
		<li>Fix the tracker on the teeth (with an unlabelled clip) or in case of an edentulous jaw with a special tracker-holding arm.</li>
		<li>Select the typical anatomical points (teeth or bone surface) on a 3D CT image of the navigation system (minimum three points).</li>
		<li>Identify the selected anatomical points in the mouth by touching them with a probe tool. (Figure 6).</li>
		<li>Perform refinement procedure on three to four areas by drawing on the surface of the anatomical structure with a probe.</li>
	</ol>
	</li>
	<li>Place the implant with navigation in local anesthesia, injecting 2 mL of articain (80 mg/2 mL articain/ampoule).
	<ol>
		<li>Measure the drill length (touching the drill to the go plate).</li>
		<li>Check the real-time visual accuracy before drilling (touching the drill to any tooth surface and checking that it is in the same position on the monitor and in the mouth).</li>
		<li>Determine the drilling point. Explore the operation site without the flap.</li>
		<li>Drill the bone with dynamic navigation control.</li>
		<li>Measure the implant length (touching the implant to the go plate).</li>
		<li>Place the implant with the handpiece wearing the tracker controlled by the dynamic navigation control system.</li>
		<li>Close the wound with 5.0 monofilament, nonabsorbable polypropylene suture or fix the prefabricated prosthetic work.</li>
	</ol>
	</li>
	<li>Make control radiologic imaging (CBCT, FOV 8 cm x 11 cm, 12 mA, 95 kV).</li>
</ol>

<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>

All authors have disclosed any and all conflicts of interest.

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 the teeth with thermoplastic material. In toothless cases, only the tracer method without a clip can be used for calibration. The clip fixed on teeth or a special holding arm fixed on the jawbone holds the optical reference base during the navigated implant surgical placement3 (Table 4).
To ensure accurate registration, the clip should be fixed in exactly the same position relative to the jawbone during implant placement. A loosely or inaccurately fixed clip can lead to navigation errors and irreversible deviation from the planned implant position. The disadvantages of using the clip calibration method are the need for clip preparation itself, adequate training of personnel, inhibited imaging in closed occlusion due to the clip(the bite planning is limited), and difficult dynamic navigation9 as a result the placement of the clip being too close to the surgical site during implant placement, causing overlap between the clip and the optical reference base on the handpiece.
In the case of navigated implant surgical placement performed with unlabeled clip, contrary to the radio-opaque clip, anatomical formations (e.g., tooth, bone) or other structures (e.g., crown) are used for calibration. In contrast to the known shape of a fixed clip, reference structures are made visible for navigation by a surface touch scan with a device called a tracer. The tracer is a pointed, pen-like device with an optical tracking base. The tracer is used to identify three to six points or even entire surfaces, which are clearly visible on the image thanks to the tracker. This provides a registration mapping between the created image and the physical surface of the patient's candidate structure. This surface detecting method is used in case of toothlessness as well.
The accuracy of the dynamic navigation system is similar to the one reported for static navigation systems. We have achieved the same result in the two calibration methods within the dynamic navigation.
With DCAIS, there is less need for exploring large bone surfaces; therefore, incisions can be reduced, and decreased mucosal flap formation can be achieved. In the case of the dynamic method, it is possible to modify the surgical plan or deviate from the plan in real-time. The dynamic implant placement system operates with shorter surgical instrumentation; therefore, it can be used in second molar regions and in the case of patients having a limited opening of the mouth. There is no need for specific drill equipment or surgical instruments for dynamic navigation systems. Monitoring the surgery on display allows for an ergonomic body position of the specialist, so the surgeon is able to achieve ideal posture1,8,10.
By using the tracer calibration of dynamic navigation, we can achieve the same accuracy and avoid the need for clip preparation. The accuracy of the methods depends on the doctor, and adequate training is essential. The method needs very precise planning, and more accurate implant positioning and prosthetic results are expected. 
The method allows for immediate implant loading (in case of strong primary stability), as the prosthesis can be prepared in advance based on the design. If the surgical procedure is accurate, the prosthesis fits the position of the implant. The main obstacles to using DCAIS are its (currently) high cost and time-consuming learning process.

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><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 implant placements.
According to our early data (Table 1, Table 2, Table 3, Figure 7, Figure 8, Figure 9, and Figure 10), when using the two calibration methods, the results showed that there is no significant correlation between the platform and angular deviation in buccolingual (BL) and mesiodistal (MD) directions. Comparing the planned and final position of the implants, the calibration with a clip proved more accurate compared to one made with a tracer, but the difference is not significant (Table 1, Table 2, Table 3, Figure 7, Figure 8, Figure 9, and Figure 10). Based on previously published data by Block et al., implant placement with a dynamic navigation system allows high-precision implant placement1. The accuracy of the intervention can be improved by training8.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/63400/63400fig01.jpg" /> 
Figure 1: Calibration with clip. Calibration by holding the tip of the measured drill to the surface of the labeled clip. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/63400/63400fig02.jpg" /> 
Figure 2: Drill calibration. Measuring the drill length by touching the drill to the go plate. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/63400/63400fig03.jpg" /> 
Figure 3: Drilling process in the mouth. Drilling the bone under dynamic navigation control. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/63400/63400fig04.jpg" /> 
Figure 4: Real-time live view of the drilling process on the monitor. Real-time control view of bone drilling. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/63400/63400fig05.jpg" /> 
Figure 5: Real-time live view of the drilling process on the monitor. Real-time control view of bone drilling. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 6" class="xfigimg" src="/files/ftp_upload/63400/63400fig06.jpg" /> 
Figure 6: Calibration with tracer. Identifying the selected anatomical points in the mouth by touching them with a probe tool. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig06large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 7" class="xfigimg" src="/files/ftp_upload/63400/63400fig07.jpg" /> 
Figure 7: Mean deviation of the measured values (difference between the planned and final position of the implants) using the two different calibration methods. Global Platform deviation (mm): spatial distance between the center of the implant platform of planned and placed implants. Platform B/L deviation (mm): spatial distance between the center of the implant platform of planned and placed implants in buccolingual dimensions. Platform M/D deviation (mm): spatial distance between the center of the implant platform of planned and placed implants in mesiodistal dimensions. Platform depth deviation (mm): spatial distance between the center of the implant platform of planned and placed implants in depth dimensions. Platform non-depth deviation (mm): the resultant of the Platform B/L and M/D deviations. Apical non-depth deviation (mm): the resultant of the apical B/L and M/D deviations. Global Apical deviation (mm): spatial distance between the center of the implant apex of planned and placed implants. Apical B/L deviation (mm): spatial distance between the center of the implant apex of planned and placed implants in buccolingual dimensions. Apical M/D deviation (mm): spatial distance between the center of the implant apex of planned and placed implants in mesiodistal dimensions.Apical depth deviation (mm): spatial distance between the center of the implant apex of planned and placed implants in depth dimensions. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig07large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 8" class="xfigimg" src="/files/ftp_upload/63400/63400fig8v2.jpg" /> 
Figure 8: Standard deviation of the measured values. The difference between the planned and final position of the implants using the two different calibration methods. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig8v2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 9" class="xfigimg" src="/files/ftp_upload/63400/63400fig09.jpg" /> 
Figure 9: Standard error of mean deviation of the measured values. The difference between the planned and final position of the implants using the two different calibration methods. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig09large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 10" class="xfigimg" src="/files/ftp_upload/63400/63400fig10.jpg" /> 
Figure 10: Analysis of the measured values. The difference between the planned and final position of the implants using the two different calibration methods. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/63400/63400fig10large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="11" style="min-width: 880px;">Mean deviation</td>
		</tr>
		<tr>
			<td style="min-width: 80px;"></td>
			<td style="min-width: 80px;">Global Platform (mm)</td>
			<td style="min-width: 80px;">Platform B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Platform M/D deviation (mm)</td>
			<td style="min-width: 80px;">Platform depth deviation (mm)</td>
			<td style="min-width: 80px;">Platform non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Apical non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Global Apical (mm)</td>
			<td style="min-width: 80px;">Apical B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Apical M/D deviation (mm)</td>
			<td style="min-width: 80px;">Apical depth deviation (mm)</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">clip</td>
			<td style="min-width: 80px;">1.68</td>
			<td style="min-width: 80px;">0.14</td>
			<td style="min-width: 80px;">-0.24</td>
			<td style="min-width: 80px;">0.53</td>
			<td style="min-width: 80px;">1.1</td>
			<td style="min-width: 80px;">1.29</td>
			<td style="min-width: 80px;">1.81</td>
			<td style="min-width: 80px;">0.18</td>
			<td style="min-width: 80px;">0,00</td>
			<td style="min-width: 80px;">0.45</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">tracer</td>
			<td style="min-width: 80px;">1.99</td>
			<td style="min-width: 80px;">0.11</td>
			<td style="min-width: 80px;">0.32</td>
			<td style="min-width: 80px;">0.86</td>
			<td style="min-width: 80px;">1.21</td>
			<td style="min-width: 80px;">1.62</td>
			<td style="min-width: 80px;">2.28</td>
			<td style="min-width: 80px;">0.31</td>
			<td style="min-width: 80px;">0.43</td>
			<td style="min-width: 80px;">0.86</td>
		</tr>
	</tbody>
</table>
Table 1: Mean deviation of the measured values. The difference between the planned and final position of the implants using the two different calibration methods.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="11" style="min-width: 880px;">Standard deviation</td>
		</tr>
		<tr>
			<td style="min-width: 80px;"></td>
			<td style="min-width: 80px;">Global Platform (mm)</td>
			<td style="min-width: 80px;">Platform B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Platform M/D deviation (mm)</td>
			<td style="min-width: 80px;">Platform depth deviation (mm)&#160;</td>
			<td style="min-width: 80px;">Platform non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Apical non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Global Apical (mm)</td>
			<td style="min-width: 80px;">Apical B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Apical M/D deviation (mm)</td>
			<td style="min-width: 80px;">Apical depth deviation (mm)</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">clip</td>
			<td style="min-width: 80px;">1.03</td>
			<td style="min-width: 80px;">0.79</td>
			<td style="min-width: 80px;">1.14</td>
			<td style="min-width: 80px;">1.29</td>
			<td style="min-width: 80px;">0.89</td>
			<td style="min-width: 80px;">1.16</td>
			<td style="min-width: 80px;">1.22</td>
			<td style="min-width: 80px;">0.79</td>
			<td style="min-width: 80px;">1.52</td>
			<td style="min-width: 80px;">1.26</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">tracer</td>
			<td style="min-width: 80px;">0.84</td>
			<td style="min-width: 80px;">0.94</td>
			<td style="min-width: 80px;">1.3</td>
			<td style="min-width: 80px;">1.3</td>
			<td style="min-width: 80px;">0.94</td>
			<td style="min-width: 80px;">1.23</td>
			<td style="min-width: 80px;">1.07</td>
			<td style="min-width: 80px;">1.12</td>
			<td style="min-width: 80px;">1.61</td>
			<td style="min-width: 80px;">1.27</td>
		</tr>
	</tbody>
</table>
Table 2: Standard deviation of the measured values. The difference between the planned and final position of the implants using the two different calibration methods.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="11" style="min-width: 880px;">Standard error of the mean deviation</td>
		</tr>
		<tr>
			<td style="min-width: 80px;"></td>
			<td style="min-width: 80px;">Global Platform (mm)</td>
			<td style="min-width: 80px;">Platform B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Platform M/D deviation (mm)</td>
			<td style="min-width: 80px;">Platform depth deviation (mm)&#160;</td>
			<td style="min-width: 80px;">Platform non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Apical non-depth deviation (mm)</td>
			<td style="min-width: 80px;">Global Apical (mm)</td>
			<td style="min-width: 80px;">Apical B/L Deviation (mm)</td>
			<td style="min-width: 80px;">Apical M/D deviation (mm)</td>
			<td style="min-width: 80px;">Apical depth deviation (mm)</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">clip</td>
			<td style="min-width: 80px;">0.16</td>
			<td style="min-width: 80px;">0.12</td>
			<td style="min-width: 80px;">0.18</td>
			<td style="min-width: 80px;">0.2</td>
			<td style="min-width: 80px;">0.14</td>
			<td style="min-width: 80px;">0.18</td>
			<td style="min-width: 80px;">0.19</td>
			<td style="min-width: 80px;">0.12</td>
			<td style="min-width: 80px;">0.24</td>
			<td style="min-width: 80px;">0.2</td>
		</tr>
		<tr>
			<td style="min-width: 80px;">tracer</td>
			<td style="min-width: 80px;">0.2</td>
			<td style="min-width: 80px;">0.23</td>
			<td style="min-width: 80px;">0.32</td>
			<td style="min-width: 80px;">0.32</td>
			<td style="min-width: 80px;">0.23</td>
			<td style="min-width: 80px;">0.3</td>
			<td style="min-width: 80px;">0.26</td>
			<td style="min-width: 80px;">0.27</td>
			<td style="min-width: 80px;">0.39</td>
			<td style="min-width: 80px;">0.31</td>
		</tr>
	</tbody>
</table>
Table 3: Standard error of mean deviation of the measured values. The difference between the planned and final position of the implants using the two different calibration methods.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td colspan="2">Dynamic navigation implantation systems</td>
		</tr>
		<tr>
			<td>advantage (+)</td>
			<td>disadvantage (-)</td>
		</tr>
		<tr>
			<td>&#183; Very precise implant placement&#160;</td>
			<td>&#183; A system failure that interferes with the spatial relationship between the reference points and the patient can lead to errors in implant bed design and implant positioning</td>
		</tr>
		<tr>
			<td>&#183; Less invasive, shorter healing time, fewer complaints</td>
			<td>&#183; Longer training period required to use the system correctly</td>
		</tr>
		<tr>
			<td>&#183; Less risk of complications (e.g. nerve damage)</td>
			<td>&#183; Costly</td>
		</tr>
		<tr>
			<td>&#183; Easy to use in small mouth openings and in the molar region</td>
			<td></td>
		</tr>
		<tr>
			<td>&#183; Does not require a separate surgical instrument set&#160;</td>
			<td></td>
		</tr>
		<tr>
			<td>&#183; Efficient use of time, planning and surgery can be performed on the same day</td>
			<td></td>
		</tr>
		<tr>
			<td>&#183; Possibility to change the position and size of the previously planned implants during surgery</td>
			<td></td>
		</tr>
		<tr>
			<td>&#183; Can also be used in narrow interdental spaces</td>
			<td></td>
		</tr>
	</tbody>
</table>
Table 4: Advantages and disadvantages of dynamic navigated implant systems.

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 ...

dynamic-navigation-for-dental-implant-placement

Nanyang Technological University

Research

JoVE Journal

Medicine

3.6K Views.  Semmelweis University. Digitale geautomatiseerde implantaatsystemen maken real-time geobjectiveerde instrumentbesturing mogelijk binnen een GPS-achtig kader. De positie van het instrument tijdens de operatie kan live worden gevolgd op een driedimensionaal beeld op een monitor. Deze techniek is nauwkeurig, minimaal invasief, heeft geen chirurgische gidssjabloon nodig en is gemakkelijk te gebruiken in een kleine mond.De planning en operatie kunnen op dezelfde dag worden uitgevoerd en aanpassing is mogelijk tij...

Video: Dynamic Navigation for Dental Implant Placement

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 ...

Surgical Placement of Catheters for Long-term Cardiovascular Exercise Testing in Swine

This protocol describes the surgical procedure to chronically instrument swine and the procedure to exercise swine on a motor-driven treadmill. Early cardiopulmonary dysfunction is difficult to diagnose, particularly in animal models, as cardiopulmonary function is often measured invasively, requiring anesthesia. As many anesthetic agents are cardiodepressive, subtle changes in cardiovascular function may be masked. In contrast, chronic instrumentation allows for measurement of cardiopulmonary function in the awake state, so that measurements can be obtained under quiet resting conditions, without the effects of anesthesia and acute surgical trauma. Furthermore, when animals are properly trained, measurements can also be obtained during graded treadmill exercise.
Flow probes are placed around the aorta or pulmonary artery for measurement of cardiac output and around the left anterior descending coronary artery for measurement of coronary blood flow. Fluid-filled catheters are implanted in the aorta, pulmonary artery, left atrium, left ventricle and right ventricle for pressure measurement and blood sampling. In addition, a 20 G&#160;catheter is positioned in the anterior interventricular vein to allow coronary venous blood sampling.
After a week of recovery, swine are placed on a motor-driven treadmill, the catheters are connected to pressure and flow meters, and swine are subjected to a five-stage progressive exercise protocol, with each stage lasting 3 min. Hemodynamic signals are continuously recorded and blood samples are taken during the last 30 sec of each exercise stage.
The major advantage of studying chronically instrumented animals is that it allows serial assessment of cardiopulmonary function, not only at rest but also during physical stress such as exercise. Moreover, cardiopulmonary function can be assessed repeatedly during disease development and during chronic treatment, thereby increasing statistical power and hence limiting the number of animals required for a study.

Here we present a protocol to assess cardiopulmonary function in awake swine, at rest and during graded treadmill exercise. Chronic instrumentation allows for repeated hemodynamic measurements uninfluenced by cardiodepressive anesthetic agents.

This protocol describes the surgical procedure to chronically instrument swine and the procedure to exercise swine on a motor-driven treadmill. Early ...

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children

Oral biofilm and its molecular analysis provide a basis for investigating various dental research and clinical questions. Knowledge of biofilm composition leads to a better understanding of cariogenic and periopathogenic mechanisms. Microbial changes taking place in the oral cavity during childhood are of interest for several reasons. The evolution of the child oral microbiota and shifts in its composition need to be analyzed further to understand and possibly prevent the onset of disease. At the same time, advanced knowledge of the natural composition of oral biofilm is needed. Early stages of caries-free permanent dentition with healthy gums provide a widely unaffected subgingival habitat that can serve as an in situ baseline for studying features of oral health and disease. Analysis of children's oral biofilm during different stages in life is thus an important theme in the field. Modern molecular analysis methods can provide comprehensive information about the bacterial diversity of such biofilms. To enable microbiota data comparison, it is important to standardize each step in the procedure for molecular data generation. This procedure spans from clinical sampling, Next Generation Sequencing (NGS), bioinformatic data processing, to taxonomic interpretation. One of the most critical factors here is biofilm sampling. Sampling in children is even more challenging in particular due to limited space in subgingival areas. We thus focus on the use of paper points for subgingival sampling. This article provides a detailed protocol for oral biofilm sampling of the subgingival sulcus, the mucosa, and saliva in children.

Changes in the oral microbiome throughout childhood are of growing interest. Comparison of different microbiome studies reveals a lack of standardized sampling protocols. Limited space makes sampling the sound subgingival sulcus of children challenging. Paper point sampling is presented here in detail as the method of choice for this area.

Oral biofilm and its molecular analysis provide a basis for investigating various dental research and clinical questions. Knowledge of biofilm composition ...

Three-dimensional Navigation-guided, Prone, Single-position, Lateral Lumbar Interbody Fusion Technique

Lateral interbody fusion provides a significant biomechanical advantage over the traditional transforaminal lumbar interbody fusion due to the large implant size and optimal implant position. However, current methods for lateral interbody cage placement require either a two-staged procedure or a single lateral decubitus position that precludes surgeons from having either full access to the posterior spine for direct decompression or comfortable pedicle screw placement.
Herein is one institution's experience with 10 cases of a prone single-position approach for simultaneous access to the anterior and posterior lumbar spine. This allows both lateral lumbar interbody cage placement, direct posterior decompression, and pedicle screw placement, all in one position. Three-dimensional (3D) navigation is utilized for increased precision in both approaching the lateral spine and interbody cage placement. The traditional blind psoas muscle tubular dilation was also modified. Tubular retractors and lateral vertebral body retractor pins were used to minimize the risks to the lumbar plexus.

The single-position, prone, lateral approach allows for both lateral lumbar interbody placement and direct posterior decompression with pedicle screw placement in one position.

Lateral interbody fusion provides a significant biomechanical advantage over the traditional transforaminal lumbar interbody fusion due to the large ...

Neuroscience

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 ...

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.

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

C-arm-Free Simultaneous OLIF51 and Percutaneous Pedicle Screw Fixation in a Single Lateral Position

Oblique lumbar interbody fusion (OLIF) is an established technique for the indirect decompression of lumbar canal stenosis. However, OLIF at the L5-S1 level (OLIF51) is technically difficult because of the anatomical structures. We present a novel simultaneous technique of OLIF51 with percutaneous pedicle screw fixation without fluoroscopy. The patient is placed in a right lateral decubitus position. A percutaneous reference pin is inserted into the right sacroiliac joint. An O-arm scan is performed, and 3D reconstructed images are transmitted to the spinal navigation system. A 4 cm oblique skin incision is made under navigation guidance along the pelvis. The internal/external and transverse abdominal muscles are divided along the muscle fibers, protecting the iliohypogastric and ilioinguinal nerves. Using a retroperitoneal approach, the left common iliac vessels are identified. Special muscle retractors with illumination are used to expose the L5-S1 intervertebral disc. After disc preparation with navigated instruments, the disc space is distracted with navigated trials. Autogenous bone and demineralized bone material are then inserted into the cage hole. The OLIF51 cage is inserted into the disc space with the help of a mallet. Simultaneously, percutaneous pedicle screws are inserted by another surgeon without changing the lateral decubitus position of the patient.
In conclusion, C-arm-free OLIF51 and simultaneous percutaneous pedicle screw fixation are performed in a lateral position under navigation guidance. This novel technique reduces surgical time and radiation hazards.

C-arm-free oblique lumbar interbody fusion at the L5-S1 level (OLIF51) and simultaneous pedicle screw fixation are performed in a lateral position under navigation guidance. This technique does not expose the surgeon or operating staff to radiation hazards.

Oblique lumbar interbody fusion (OLIF) is an established technique for the indirect decompression of lumbar canal stenosis. However, OLIF at the L5-S1 ...

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 ...

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, ...

A Pilot Study Showing Application of Palatal Bone Harvesting Under Dynamic Navigation Guidance in Oral Implantology

In cases of insufficient bone volume in the implant area, bone augmentation surgery is often required to ensure an adequate amount of bone around the implant. In autologous bone grafting procedures, some patients face insufficient bone volume at conventional intraoral bone harvesting sites. Due to the high difficulty associated with completing palatal osteotomies freehand, fewer palatal lateral osteotomies have been reported, and palatal bone blocks are not routinely used in bone augmentation procedures. With the development of digitally guided implant technology, palatal bone harvesting has become feasible. In this paper, we will present a method of obtaining a circumferential bone block of the palate for implant surgical application through dynamic navigation guidance. A total of three patients had undergone this procedure to obtain circumferential palatal bone blocks and completed bone augmentation surgery. The bone augmentation results in the implanted area have been favorable, and there has been some bone recovery at the harvesting site. This is a safe and effective way to obtain intraoral bone blocks.

The protocol introduces a novel surgical method for palatal ring bone block harvesting using dynamic navigation guidance, addressing the challenge of insufficient bone volume in typical intraoral grafting areas and offering a viable solution for effective bone augmentation in implant dentistry.

In cases of insufficient bone volume in the implant area, bone augmentation surgery is often required to ensure an adequate amount of bone around the ...

Dynamic Navigation for Dental Implant Placement

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