Accuracy of 3 calibration methods of computer-assisted dynamic navigation for implant placement: An in vitro study

Accuracy of Two Robotic Computer-Aided Implant System Registration Methods for Dental Implantation: A Prospective Study

BACKGROUND

Robot-assisted implant surgery has been shown to achieve high levels of accuracy. However, there is currently a paucity of clinical studies evaluating the accuracy of marker-based intraoral scanner (IOS) registration (IR) methods.

PURPOSE

The purpose of this study was to compare the accuracy of the marker-based cone beam computed tomography (CBCT) registration (CR) method and the IR method in the dental implant in the robotic computer-aided implant system (R-CAIS).

MATERIALS AND METHODS

This retrospective study included 20 participants, with 10 undergoing implant surgery using the CR method within a robotic system, and the remaining 10 receiving implants using the IR method. Preoperative CBCT images used for implant planning were aligned with the postoperative CBCT images to assess and quantify positional deviations in implant placement. The primary outcome measures were FRE, entry deviation, apical deviation, and angular deviation. A Student's t-test was performed to compare differences between the two groups, with a p-value of < 0.05 considered statistically significant.

RESULTS

The mean ± standard deviation values for FRE were 0.027 ± 0.007 mm for the CR group and 0.031 ± 0.006 mm for the IR group (p = 0.149). The mean ± standard deviation values for entry deviation were 0.58 ± 0.11 mm for the CR group and 0.53 ± 0.15 mm for the IR group (p = 0.072). The mean ± standard deviation values for apical deviation were 0.52 ± 0.12 mm for the CR group and 0.50 ± 0.14 mm for the IR group (p = 0.730). The mean ± standard deviation values for apical deviation were 1.10 ± 0.34 mm for the CR group and 1.17 ± 0.23 mm for the IR group (p = 0.730).

CONCLUSIONS

In R-CAIS, the IR method demonstrated accuracy comparable to that of the CR method, with both methods yielding clinically satisfactory outcomes.

Accuracy of bi-coordinate and multi-coordinate handpiece calibration methods for robot-assisted implant placement

STATEMENT OF PROBLEM

To ensure accurate robot-assisted surgery, it is essential to identify the handpiece position at the end effector of the robotic arm. Clinically, the relationship between the optical tracking device and the handpiece has been typically confirmed by using a calibration plate at the end effector of the robotic arm. However, the accuracy of the handpiece calibration methods for robot-assisted implant placement remains unclear.

PURPOSE

The purpose of this in vitro study was to evaluate the accuracy of bi-coordinate and multi-coordinate handpiece calibration methods, as well as the multi-coordinate handpiece plate under partial obstruction, in the context of robot-assisted implant placement.

MATERIAL AND METHODS

In total, 120 implants were divided into 6 groups based on the calibration plate used in the study: bi-coordinate handpiece calibration plate for the maxilla (Bmx), bi-coordinate handpiece calibration plate for the mandible (Bmn), multi-coordinate handpiece calibration plate for the maxilla (Mmx), multi-coordinate handpiece calibration plate for the mandible (Mmn), partially obscured multi-coordinate handpiece calibration plate for the mandible with the primary coordinate unblocked and the auxiliary coordinate covered (MmnPrim), and partially obscured multi-coordinate handpiece calibration plate for the mandible with the auxiliary coordinate unblocked and the primary coordinate covered (MmnAux). Calibration of the robotic arm was conducted separately for each group. Then the robot autonomously performed osteotomies and implant placements at the first and second premolars according to the preoperative plan. Following surgery, the robotic software program calculated the deviation values between the planned and actual implant positions. Differences between the test groups were analyzed using 1-way analysis of variance (ANOVA) and the Bonferroni post hoc test (α=.05).

RESULTS

The ranges of angular deviation and 3-dimensional deviations at the implant platform and apex across the 6 groups were 0.30 degrees to 0.48 degrees, 0.31 to 0.36 mm, and 0.31 to 0.38 mm, respectively. No statistically significant differences were found among the groups (P>.05).

CONCLUSIONS

Both the bi-coordinate and multi-coordinate handpiece calibration methods demonstrated acceptable accuracy for robot-assisted implant placement. The multi-coordinate calibration plate provides a feasible method for robot calibration in scenarios where the mandible is partially obstructed.

Accuracy of a calibration method based on cone beam computed tomography and intraoral scanner data registration for robot-assisted implant placement: An in vitro study

STATEMENT OF PROBLEM

Robotic systems have shown promise for implant placement because of their accuracy in identifying surgical positions. However, research on the accuracy of patient calibration methods based on cone beam computed tomography (CBCT) and intraoral scanner (IOS) data registration is lacking.

PURPOSE

The purpose of this in vitro study was to develop a calibration method based on the registration of CBCT and IOS data of a robot-assisted system for implant placement, evaluate the accuracy of this calibration method, and explore the accuracy of robot-assisted surgery at different implant positions.

MATERIAL AND METHODS

Twenty standardized, polyurethane, partially edentulous maxillary typodonts were divided into 2 groups: one group used a calibration method based solely on CBCT data (CBCT group), and the other used a calibration method based on the registration of CBCT and IOS data (IOS group). Four implants were planned for each typodont in the right second premolar, left central incisor, left first premolar, and left second molar positions. The robot performed the osteotomies and implant placement step by step according to the preoperative plan. The operating software program automatically measured the deviation between the planned and actual implant position. Two-way analysis of variance (ANOVA) and the least significant difference (LSD) post hoc test (α=.05) were used to analyze differences between the test groups.

RESULTS

The angular deviation and 3-dimensional deviations at implant platform and apex between the 2 calibration methods did not significantly differ among the 4 implant positions (P>.05). The horizontal and depth deviations at the implant platform and apex levels between the 2 calibration methods did not significantly differ among the 4 implant positions (P>.05). In the anterior region (left central incisor), the CBCT group showed higher horizontal deviation at both the implant platform and apex compared with the IOS group (P<.05). Conversely, the IOS group had greater depth deviation at both the implant platform and apex than the CBCT group (P<.05). In the posterior region, with or without distal extension (right second premolar, left first premolar, and left second molar), no statistically significant differences were found between the 2 calibration methods (P>.05).

CONCLUSIONS

The calibration method that was based on the registration of CBCT and IOS data demonstrated high accuracy. No significant differences in the accuracy of the calibration methods for robot-assisted implant placement were found between the CBCT group and IOS group.

Accuracy of dental implant surgery with freehand, static computer-aided, dynamic computer-aided, and robotic computer-aided implant systems: An in vitro study

STATEMENT OF PROBLEM

The static computer-aided implant system (S-CAIS), dynamic computer-aided implant system (D-CAIS), and robotic computer-aided implant system (R-CAIS) have been used to improve the accuracy of implant placement. However, the accuracy of freehand (FH),S-CAIS, D-CAIS, and R-CAIS implant placement has not been compared and verified under identical conditions.

PURPOSE

The purpose of this in vitro study was to compare the accuracy of dental implant placement using S-CAIS, D-CAIS, R-CAIS, and FH techniques under identical conditions.

MATERIAL AND METHODS

A total of 60 standardized polyurethane resin models with missing mandibular teeth were prepared and divided into 4 groups: FH, S-CAIS, D-CAIS, and R-CAIS, each consisting of 15 models. Preoperative implant planning was performed using cone beam computed tomography (CBCT), and 2 implants were placed in each model using the FH, S-CAIS, D-CAIS, and R-CAIS techniques, respectively. Postoperatively, CBCT scans were made for analysis of the entry, apical, and angle deviations. The error results among groups were compared using 1-way analysis of variance or a nonparametric test. The Dunnett test was used for post hoc comparison (α=.05).

RESULTS

The mean ±standard deviation values for entry deviation were 1.09 ±0.33 mm for the FH group, 0.72 ±0.33 mm for S-CAIS, 0.69 ±0.29 mm for D-CAIS, and 0.48 ±0.18 mm for R-CAIS (P<.05). The mean (quartiles) apical deviations were 1.01 (0.94 -1.22) for the FH group, and the mean ±standard deviation values were 0.87 ±0.07 mm for the S-CAIS group, 0.64 ±0.05 mm for D-CAIS, and 0.47 ±0.03 mm for R-CAIS (P<.05). The mean ±standard deviation values for angle deviation for the FH group were 2.74 ±0.84 degrees, 1.99 ±0.76 degrees for S-CAIS, 0.85 ±0.46 degrees for D-CAIS, and 0.53 ±0.20 degrees for R-CAIS (P<.05).

CONCLUSIONS

R-CAIS is a reliable implant placement method, demonstrating better implant accuracy compared with the S-CAIS, D-CAIS, and FH techniques.

Accuracy of different registration areas using active and passive dynamic navigation systems in dental implant surgery: An in vitro study

OBJECTIVES

To gauge the relative accuracy of the use of passive and active dynamic navigation systems when placing dental implants, and to determine how registration areas affect the performance of these systems.

MATERIALS AND METHODS

Eighty implants were assigned to be placed into 40 total resin mandible models missing either the left or right first molars using either passive or active dynamic navigation system approaches. U-shaped tube registration devices were fixed in the edentulous site for 20 models each on the left or right side. Planned and actual implant positions were superimposed to assess procedural accuracy, and parameters including 3D entry deviation, angular deviation, and 3D apex deviation were evaluated with Mann-Whitney U tests and Wilcoxon signed-rank tests.

RESULTS

Respective angular, entry, and apex deviation values of 1.563 ± 0.977°, 0.725 ± 0.268 mm, and 0.808 ± 0.284 mm were calculated for all included implants, with corresponding values of 1.388 ± 1.090°, 0.789 ± 0.285 mm, and 0.846 ± 0.301 mm in the active group and 1.739 ± 0.826°, 0.661 ± 0.236 mm, and 0.769 ± 0.264 mm in the passive group. Only angular deviation differed significantly among groups, and the registration area was not associated with any significant differences among groups.

CONCLUSIONS

Passive and active dynamic navigation approaches can achieve comparable in vitro accuracy. Registration on one side of the missing single posterior tooth area in the mandible can complete single-tooth implantation on both sides of the posterior teeth, highlighting the promise of further clinical research focused on this topic.

The impacts of registration-and-fixation device positioning on the performance of implant placement assisted by dynamic computer-aided surgery: A randomized controlled trial

OBJECTIVES

To assess the efficacy of dynamic computer-aided surgery (dCAS) in replacing a single missing posterior tooth, we compare outcomes when using registration-and-fixation devices positioned anterior or posterior to the surgical site. Registration is performed on either the anterior or opposite posterior teeth.

METHODS

Forty individuals needing posterior single-tooth implant placement were randomly assigned to anterior or posterior registration. Nine parameters were analyzed to detect the deviations between planned and actual implant placement, using Mann-Whitney and t-tests for nonnormally and normally distributed data, respectively.

RESULTS

The overall average angular deviation for this study was 2.08 ± 1.12°, with the respective average 3D platform and apex deviations of 0.77 ± 0.32 mm and 0.88 ± 0.32 mm. Angular deviation values for individuals in the anterior and posterior registration groups were 1.58°(IQR: 0.98°-2.38°) and 2.25°(IQR: 1.46°-3.43°), respectively (p = .165), with 3D platform deviations of 0.81 ± 0.29 mm and 0.74 ± 0.36 mm (p = .464), as well as 3D apex deviations of 0.89 ± 0.32 mm and 0.88 ± 0.33 mm (p = .986). No significant variations in absolute buccolingual (platform, p = .659; apex, p = .063), apicocoronal (platform, p = .671; apex, p = .649), or mesiodistal (platform, p = .134; apex, p = .355) deviations were observed at either analyzed levels.

CONCLUSIONS

Both anterior and posterior registration approaches facilitate accurate dCAS-mediated implant placement for single missing posterior teeth. The device's placement (posterior-to or anterior-to the surgical site) did not affect the clinician's ability to achieve the planned implant location.

Placement accuracy and primary stability of implants in the esthetic zone using dynamic and static computer-assisted navigation: A retrospective case-control study

STATEMENT OF PROBLEM

Both the placement accuracy and primary stability of implants are important to implant therapy in the esthetic zone. The effect of dynamic and static computer-assisted navigation on the primary stability of implants in the esthetic zone remains uncertain.

PURPOSE

The purpose of this case-control study was to investigate the effect of dynamic and static computer-assisted navigation on the placement accuracy and primary stability of implants in the esthetic zone.

MATERIAL AND METHODS

Partially edentulous participants who received at least 1 implant in the anterior maxilla using either fully guided static or dynamic computer-assisted implant surgery (s-CAIS, d-CAIS) from January 2020 to February 2022 were screened. Participant demographic information, timing of implant placement, primary stability represented by the insertion torque value (ITV) in Ncm, and implant survival were collected from the treatment record. Bone quality at the implant sites was determined according to the Lekholm and Zarb classification. The accuracy of implant placement represented by the linear (platform: Dpl, mm; apex: Dap, mm) and angular deviations (axis: Dan, degree) between the planned and placed implants was evaluated based on the preoperative surgical plan and postoperative cone beam computed tomography (CBCT) data. A statistical analysis of the data was completed by using the chi-squared, Fisher exact, Student t, and Mann-Whitney U tests (α=.05).

RESULTS

A total of 32 study participants (38 implants) were included. The groups of s-CAIS (16 participants, 18 implants) and d-CAIS (16 participants, 20 implants) were statistically comparable in sex (P=.072), age (P=.548), bone quality (P=.671), and timing of implant placement (P=.719). All implants survived during an average follow-up period of 13 months. The d-CAIS group showed close linear deviations (Dpl 1.07 ±0.57 mm, Dap 1.26 ±0.53 mm) but lower angular deviation (Dan 2.14 ±1.20 degrees) and primary stability (ITV 25.25 ±7.52 Ncm) than the s-CAIS group (Dpl 0.92 ±0.46 mm, Dap 1.31 ±0.43 mm, Dan 3.31 ±1.61 degrees, ITV 30.56 ±11.23 Ncm, PDpl=.613, PDap=.743, PDan=.016, PITV=.028).

CONCLUSIONS

Comparable linear positioning accuracy and higher angular deviation were found for implants placed in the esthetic zone by using s-CAIS than when using d-CAIS. Higher primary stability of implants may be achieved by using s-CAIS, as s-CAIS seemed to have higher osteotomy accuracy than d-CAIS.

Comparison of the accuracy of dental implant placement using dynamic and augmented reality-based dynamic navigation: An in vitro study

Background/purpose

Augmented reality has been gradually applied in dental implant surgery. However, whether the dynamic navigation system integrated with augmented reality technology will further improve the accuracy is still unknown. The purpose of this study is to investigate the accuracy of dental implant placement using dynamic navigation and augmented reality-based dynamic navigation systems.

Materials and methods

Thirty-two cone-beam CT (CBCT) scans from clinical patients were collected and used to generate 64 phantoms that were allocated to the augmented reality-based dynamic navigation (ARDN) group or the conventional dynamic navigation (DN) group. The primary outcomes were global coronal, apical and angular deviations, and they were measured after image fusion. A linear mixed model with a random intercept was used. A P value < 0.05 was considered to indicate statistical significance.

Results

A total of 242 dental implants were placed in two groups. The global coronal, apical and angular deviations of the ARDN and DN groups were 1.31 ± 0.67 mm vs. 1.18 ± 0.59 mm, 1.36 ± 0.67 mm vs. 1.39 ± 0.55 mm, and 3.72 ± 2.13° vs. 3.1 ± 1.56°, respectively. No significant differences were found with regard to coronal and apical deviations (P = 0.16 and 0.6, respectively), but the DN group had a significantly lower angular deviation than the ARDN group (P = 0.02).

Conclusion

The augmented reality-based dynamic navigation system yielded a similar accuracy to the conventional dynamic navigation system for dental implant placement in coronal and apical points, but the augmented reality-based dynamic navigation system yielded a higher angular deviation.

Accuracy and efficiency of a calibration approach in dynamic navigation for implant placement: An in vitro study

Background/purpose

Computer-assisted dynamic navigation surgery could provide accurate implant placement. However, its low efficiency was always criticized by dental surgeons. The purpose of this study was to evaluate the accuracy and efficiency of a calibration approach with reflective wafers in dynamic navigation for implant placement.

Materials and methods

Eighty implants were placed in the standardized polyurethane mandibular models under dynamic navigation and divided into 2 groups according to the calibration methods (n = 40). The U-shaped tube (UT) group used a prefabricated U-shaped tube embedded with radiopaque markers. The reflective wafers (RW) group used a fixation with 3 round reflective wafers as markers. Postoperative cone beam computed tomography images were obtained for implants deviation analyses. The calibration time was used to evaluate the efficiency of the 2 methods.

Results

Significant differences were found in the trueness and efficiency between the 2 groups (P < 0.05). The 3D deviations at the implant platform and apex were smaller in UT group (0.89 ± 0.28 and 0.79 ± 0.30 mm, respectively) than in the RW group (0.99 ± 0.28 and 0.98 ± 0.30 mm, respectively). The angular deviation was larger in the UT group (2.16 ± 1.12°) than in the RW group (1.53 ± 0.88°). The calibration approach of RW group was more efficient than the UT group (2.05 ± 0.55 and 7.50 ± 0.71 min, respectively).

Conclusion

The calibration method of RW improved the efficiency significantly and achieved equivalent trueness with UT for dynamic navigation during implant placement.

Accuracy and Efficiency of Endodontic Microsurgery Assisted by Dynamic Navigation Based on Two Different Registration Methods: An In Vitro Study

INTRODUCTION

This study aimed to compare the accuracy and efficiency of dynamic navigation-assisted endodontic microsurgery (DN-EMS) using two different registration methods.

METHODS

Three-dimensional-printed jaw models, including 40 teeth, were divided into two groups (n = 20). Cone-beam computed tomography images of all teeth were scanned under the same exposing parameters. An endodontic dynamic navigation system (DHC-ENDO1) was used to plan the drilling paths. Dynamic navigation-assisted endodontic microsurgery (DN-EMS) was performed using either U-shaped tube (UT) or tooth cusp (TC) registration method. The accuracy was determined by platform deviation, end deviation, angular deviation, resection angle, and resection length deviation. The registration efficiency was defined as the time required to complete the registration procedure. Osteotomy volume of each resection was calculated by Mimics 21.0. Statistical analyses were performed using IBM SPSS Statistics 24.0. Comparisons between groups were performed using the independent sample t test or Mann-Whitney U test. P < .05 was adopted as significant difference.

RESULTS

The UT group was significantly more accurate in terms of mean platform deviation, end deviation, angular deviation, and resection angle (P < .05). Resection length deviation did not differ significantly between the registration groups. The UT group was significantly more efficient than the TC group (P < .05). No significant differences were found in the osteotomy volumes between the two groups.

CONCLUSIONS

In the model-based surgical simulation comparison, DN-EMS based on UT registration is more accurate and efficient than the TC method but requires an additional registration device. TC technique may be a reasonable alternative to UT registration in certain clinical tasks.

Accuracy of automatic and manual dynamic navigation registration techniques for dental implant surgery in posterior sites missing a single tooth: A retrospective clinical analysis

OBJECTIVES

To assess the relative accuracy of manual (U-shaped tube) and automatic (two-in-one) dynamic navigation registration techniques for implant surgery performed in posterior sites missing one tooth.

MATERIALS AND METHODS

This study included 58 partially edentulous patients with 58 implants, including 31 and 27 in the manual and automatic groups. Deviations between the planned and actual implant placement were assessed.

RESULTS

The angular deviation in the overall study cohort was 2.54 ± 1.21°, while the 3D deviations at the implant platform and apex were 0.90 ± 0.46 mm and 1.04 ± 0.47 mm, respectively. The respective angular deviations in the manual and automatic groups were 2.82 ± 1.17° and 2.21 ± 1.19° (p > .05), while platform deviations were 0.89 ± 0.48 mm and 0.91 ± 0.45 mm (p > .05), and apex deviations were 0.99 ± 0.48 mm and 1.11 ± 0.46 mm (p > .05). No significant differences in absolute buccolingual, mesiodistal, or apicocoronal deviations were detected between these groups at either level (p > .05) nor were did deviation distributions differ in the buccolingual, mesiodistal, or apicocoronal directions at the platform or apex levels (p > .05).

CONCLUSIONS

Manual and automatic dynamic navigation registration techniques can achieve excellent accuracy when placing implants in posterior sites missing a single tooth. The two-in-one automatic registration technique can reduce the amount of time and intraoperative steps necessary to complete the registration process relative to the manual U-shaped tube registration technique. Further follow-up studies are necessary to expand on these results.

Proposal and Validation of a New Nonradiological Method for Postoperative Three-Dimensional Implant Position Analysis Based on the Dynamic Navigation System: An In Vitro Study

PURPOSE

To propose a novel, radiation-free method for postoperative three-dimensional (3D) position analysis of dental implants based on the dynamic navigation system (DNS) and evaluate its accuracy in vitro.

METHODS

A total of 60 implants were digitally planned and then placed in the standardized plastic models with a single-tooth gap and a free-end gap under the guidance of the DNS. Postoperative 3D positions of the inserted implants were evaluated using specially designed navigation-based software, and its datasets were superimposed onto those of cone beam computed tomography (CBCT) for accuracy analyses. Deviations at the coronal, apical, and angular levels were measured and statistically analyzed.

RESULTS

The mean 3D deviation was 0.88 ± 0.37 mm at the entry point and 1.02 ± 0.35 mm at the apex point. The mean angular deviation was 1.83 ± 0.79 degrees. No significant differences were noted in the deviations between implants placed in the single-tooth gap and the free-end situation (p > 0.05) or between different tooth positions at distal extensions (p > 0.05).

CONCLUSIONS

This non-radiographic method provides facile, efficient, and reliable postoperative implant position evaluation and may be a potential substitute for CBCT, particularly for implants placed under the guidance of dynamic navigation.