Guided and Prosthetically Driven Bone Augmentation Using the Shell Technique and Allogeneic Cortical Plate: A Prospective Case Series

PURPOSE

To describe the use of digital technology to surgically guide the shell technique using allogenic cortical plates for a fully guided bone augmentation procedure.

MATERIALS AND METHODS

A total of 10 patients who required bone augmentation for implant placement were included in this study. Allogenic cortical plates were planned using CAD/CAM to have identical thickness to the original cortical plates, then were digitally positioned and shaped to outline the bone defect according to the existing anatomical details. A cutting pattern and a surgical template were manufactured according to the digitally preplanned bone graft and the intraoral setting.

RESULTS

A total of 12 horizontal bone grafting procedures were performed using the shell technique with allogenic cortical plates. All grafting procedures were deemed successful and allowed for ideal 3D implant positioning. Of the 12 bone grafting procedures, which used a surgical template to position the cortical plate, 3 required an adjustment to reposition the plate to a more ideal position.

CONCLUSIONS

Digital technology was used to create a surgical template to guide the shell bone grafting technique with allogenic cortical plates. All surgical templates offered a fixed support to hold the cortical allogenic plate in the preplanned position, offering a predictable, simplified, and accurate guided bone grafting procedure. Further studies on a larger population of patients are necessary to assess those results and to verify the treatment approach described in this study.

Effect of prefabricated immediate interim prosthesis design and insertion workflow on seating accuracy on implants placed via static computer-assisted implant surgery: A cross-sectional in vitro study

BACKGROUND

Immediate implant restoration by prefabricated prosthesis has multiple benefits. However, the design and insertion workflow of the prosthesis may influence the seating.

PURPOSE

Evaluation of seating accuracy of prefabricated interim prosthesis of different designs and insertion workflows for immediate restoration of implants placed via static computer-assisted implant surgery (sCAIS).

MATERIALS AND METHODS

A maxillary model without incisors was used to plan for two implants at the lateral incisor locations. According to the planned implants, sCAIS surgical template and a four-unit interim prosthesis were designed. Four prostheses were fabricated based on the design and insertion workflow. The first prosthesis involved complete fabrication (CF) of the interim prosthesis, where the interim prosthesis is fabricated for laboratory attachment to abutments. The other three prostheses were produced by partial fabrication (PF), where the interim prosthesis shell was produced with internal spacing between the fitting surface and the abutments. The PF prostheses were cemented on abutments attached to the inserted implants. Three different PF prosthesis designs were included with different levels of internal spacing: 100 μm (PF.1), 200 μm (PF.2), and 300 μm (PF.3). A total of 15 surgical models received implants on which each prosthesis was seated and scanned by a laboratory scanner. The vertical, horizontal, and proximal contact errors were measured.

RESULTS

Although all prostheses were seated on every model, the CF prostheses had greater vertical error, followed by PF.1, PF.2, and PF.3 prostheses, respectively. A similar pattern was observed for proximal contact error, where PF.3 was most superior. PF.3 prostheses had the least horizontal error than the other prostheses.

CONCLUSIONS

All interim prostheses experienced errors at the vertical, horizontal, and proximal surfaces, which can be attributed to deviations of the inserted implants. The PF of interim prosthesis with increased internal spacing for intraoral insertion appeared to reduce seating errors.

Computer-guided miniscrew insertion in the paramedian and parapalatal area of the palatal vault: low failure rate and no learning curve required to obtain predictable results?

AIM

To evaluate the failure rate of palatal computer-guided miniscrews, placed in paramedian and parapalatal regions for orthodontic purposes. In addition, to investigate the presence of a learning curve using computer guided miniscrew insertion, and to evaluate the peri-implant soft tissues response at 2-, 6- and 12- month follow-ups.

MATERIALS AND METHODS

202 palatal computer-guided miniscrews were inserted in 78 subjects for orthodontic purposes. A surgical guide was designed after planning the appropriate insertion sites on three-dimensional images created by the fusion of cone-beam computed tomography (CBCT) and digital dental model images. The devices were disassembled monthly to perform the percussion test and to evaluate the mobility of each miniscrew. To determine the presence of a learning curve, the time of miniscrew failures and the number of surgeries were evaluated. Bleeding on probing (BOP) and probing pocket depth (PPD) were recorded for each miniscrew, at 2- (T0), 6- (T1), and 12-month follow ups (T2).

RESULTS

An immediate failure rate of 4.95%, due to lack of primary stability immediately following miniscrew insertion, was recorded, with statistically significant higher failure rate of parapalatal miniscrews (P= 0.00). Miniscrew failure occurred at random time, with an absence of a learning curve. The BOP (mean: 3.13%) and PPD (mean: 1.68mm) measurements remained stable over time.

CONCLUSIONS

Computer-guided miniscrew insertion in the palatal vault showed a low failure rate without a determined learning curve to obtain predictable results and with long-term stability of peri-implant soft tissues indexes.

Immediate vs. Delayed Placement of Immediately Provisionalized Self-Tapping Implants: A Non-Randomized Controlled Clinical Trial with 1 Year of Follow-Up

This study aimed to examine the clinical and esthetic outcomes of immediately provisionalized self-tapping implants placed in extraction sockets or healed edentulous ridges one year after treatment. Sixty patients in need of a single implant-supported restoration were treated with self-tapping implants (Straumann BLX) and immediate provisionalization. The implant stability quotient (ISQ) and insertion torque were recorded intraoperatively. After one year in function, the implant and prosthesis survival rate, pink esthetic score (PES), white esthetic score (WES), and marginal bone levels (MBL) were assessed. Sixty patients received 60 self-tapping implants. A total of 37 implants were placed in extraction sockets and 23 in edentulous ridges, and then all implants were immediately provisionalized. All implants achieved a high implant stability with a mean insertion torque and ISQ value of 58.1 ± 14.1 Ncm and 73.6 ± 8.1 Ncm, respectively. No significant differences were found between healed vs. post-extractive sockets (p = 0.716 and p = 0.875), or between flap vs. flapless approaches (p = 0.862 and p = 0.228) with regards to the insertion torque and ISQ value. Nonetheless, higher insertion torque values and ISQs were recorded for mandibular implants (maxilla vs. mandible, insertion torque: 55.30 + 11.25 Ncm vs. 62.41 + 17.01 Ncm, p = 0.057; ISQ: 72.05 + 8.27 vs. 76.08 + 7.37, p = 0.058). One implant did not osseointegrate, resulting in an implant survival rate of 98.3%. All implants achieved PES and WES scores higher than 12 at the 1-year follow-up. The clinical use of newly designed self-tapping implants with immediate temporization was safe and predictable. The implants achieved a good primary stability, high implant survival rate, and favorable radiographic and esthetic outcomes, regardless of the immediate or delayed placement protocols.

Accuracy of Augmented Reality-Assisted Navigation in Dental Implant Surgery: Systematic Review and Meta-analysis

BACKGROUND

The novel concept of immersive 3D augmented reality (AR) surgical navigation has recently been introduced in the medical field. This method allows surgeons to directly focus on the surgical objective without having to look at a separate monitor. In the dental field, the recently developed AR-assisted dental implant navigation system (AR navigation), which uses innovative image technology to directly visualize and track a presurgical plan over an actual surgical site, has attracted great interest.

OBJECTIVE

This study is the first systematic review and meta-analysis study that aimed to assess the accuracy of dental implants placed by AR navigation and compare it with that of the widely used implant placement methods, including the freehand method (FH), template-based static guidance (TG), and conventional navigation (CN).

METHODS

Individual search strategies were used in PubMed (MEDLINE), Scopus, ScienceDirect, Cochrane Library, and Google Scholar to search for articles published until March 21, 2022. This study was performed in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and registered in the International Prospective Register of Systematic Reviews (PROSPERO) database. Peer-reviewed journal articles evaluating the positional deviations of dental implants placed using AR-assisted implant navigation systems were included. Cohen d statistical power analysis was used to investigate the effect size estimate and CIs of standardized mean differences (SMDs) between data sets.

RESULTS

Among the 425 articles retrieved, 15 articles were considered eligible for narrative review, 8 articles were considered for single-arm meta-analysis, and 4 were included in a 2-arm meta-analysis. The mean lateral, global, depth, and angular deviations of the dental implant placed using AR navigation were 0.90 (95% CI 0.78-1.02) mm, 1.18 (95% CI 0.95-1.41) mm, 0.78 (95% CI 0.48-1.08) mm, and 3.96° (95% CI 3.45°-4.48°), respectively. The accuracy of AR navigation was significantly higher than that of the FH method (SMD=-1.01; 95% CI -1.47 to -0.55; P<.001) and CN method (SMD=-0.46; 95% CI -0.64 to -0.29; P<.001). However, the accuracies of the AR navigation and TG methods were similar (SMD=0.06; 95% CI -0.62 to 0.74; P=.73).

CONCLUSIONS

The positional deviations of AR-navigated implant placements were within the safety zone, suggesting clinically acceptable accuracy of the AR navigation method. Moreover, the accuracy of AR implant navigation was comparable with that of the highly recommended dental implant-guided surgery method, TG, and superior to that of the conventional FH and CN methods. This review highlights the possibility of using AR navigation as an effective and accurate immersive surgical guide for dental implant placement.

Accuracy of dynamic implant navigation surgery performed by a novice operator

AIM

The main objective was to evaluate the accuracy of dynamic navigation-guided surgery (DNGS) for implant positioning performed by a novice operator. The secondary objectives were to analyze the operator's learning curve and identify possible complications deriving from the technique.

MATERIALS AND METHODS

Twenty-five implants were placed in eight partially edentulous human heads. Preoperative CBCT scans were imported to planning software to determine the implant positions. Implants were placed using a dynamic navigation system. Postoperative CBCTs were superimposed onto the implant planning images. Discrepancies between the virtually planned implant positions and the postoperative positions were evaluated by measuring horizontal platform deviation, apex deviation, apicocoronal (vertical) deviation, and angular deviation.

RESULTS

Mean platform, apex, vertical, and angle deviations were 1.55 ± 0.81 mm, 2.45 ± 0.84 mm, 1.59 ± 0.70 mm, and 5.56 ± 4.03 degrees, respectively. No significant differences were found between the maxilla and mandible or between anterior and posterior sites. A flat learning curve was observed, with the exception of the implant platform, where a tendency toward improvement in accuracy was observed between the 8th and the 17th implant placed. No complications were reported.

CONCLUSIONS

Based on the results of a study performed by a novice operator on a cadaveric model, DNGS allows accurate implant placement within a 2-mm safety margin in terms of implant platform and vertical positions, and a 3-mm margin in apical vicinities. The technique requires practice to learn the required eye-hand coordination. (Int J Comput Dent 2022;25(4):377-0; doi: 10.3290/j.ijcd.b2588207).

Comparison of Different Types of Static Computer-Guided Implant Surgery in Varying Bone Inclinations

This research aimed to compare the accuracy of dental implant placement among three types of surgical guide: metal sleeve with key handle (Nobel guide, Nobel Biocare, Göteborg, Sweden), metal sleeve without key handle, and non-sleeve without key handle (Dentium full guide kit, Dentium Co., Seoul, Korea) when placing the implant in different bone inclinations. A total of 72 polyurethane bone models were fabricated in different inclinations (0°, 45°, and 60°). The dental implants were placed in bone models following the company’s recommendations. After dental implants were installed, the digital scans were done by an extraoral scanner. The deviations of the dental implant position were evaluated by superimposition between post-implant placement and reference model by using GOM inspect software. The deviation measurement was shown in 5 parameters: angular deviation, 3D deviation at the crest, 3D deviation at the apex, lateral linear deviation, and vertical linear deviation. The data were analyzed using One-way ANOVA and post-hoc tests at a significance level of 0.05. The accuracy of the dental implant position was not significantly influenced by the difference in the surgical guide system (p > 0.05). There were significant differences between placed and planned implant positions in the different inclinations of the bone. A significant difference was found in all parameters of 0° and 60° bone inclinations (p < 0.05). At 0° and 45°, angulated bone showed significant differences except in 3D deviation at the apex. Between 45° and 60° were significant differences only in angular deviation. Within the limitations of this study, the accuracy of implant placement among three types of surgical guides (Non-sleeve without key handle, Metal sleeve without key handle, and Metal sleeve with key handle) from two companies (Dentium and Nobel Biocare) was similar. Hence, the operators can choose the surgical guide system according to their preference. The inclination of bone can influence the angulation of dental implants.

Novel endodontic microsurgery treatment for maxillary premolar vertical root fracture based on 3D technology

3D technology has been applied in both surgery simulation and guidance in endodontic microsurgery. Treatment options are still limited for vertical root fracture (VRF) in inaccessible areas that require accurate resection, especially in single-rooted teeth. This case illustrates successful treatment based on 3D technology. The literature on endodontic microsurgery of VRF is summarized. A 27-year-old woman presented with periapical lesions and apical root resorption of a maxillary premolar. After endodontic microsurgery was arranged, unexpected VRF was discovered through CBCT. Using a 3D-printed template, the root fracture was precisely removed with minimal damage. A literature review revealed a total of 12 articles published since 1946 on this topic. The 3D-printed template facilitated endodontic microsurgery, indicating reliable location of the root fracture and reduction in iatrogenic injury.

Factors Influencing the Accuracy of Freehand Implant Placement: A Prospective Clinical Study

(1) Background: The objective of implant prosthetic restoration is to ensure the best possible rehabilitation of function and esthetics. Optimal positioning of the implant with regard to the bone availability, surrounding soft tissue, and prosthetic sustainability should be strived for during implant placement. The factors influencing freehand implant placement and the accuracy achieved with this procedure are investigated in this prospective clinical study. (2) Methods: Implants were placed in the single-tooth edentulous sites of the premolar and molar areas in 52 patients. Three-dimensional (3D)-planning was performed virtually prior to the freehand implant operation, and the desired position of the implant was provided to the surgeon. (3) Results: The deviations between the planned and the actually achieved position with freehand implant placement showed the following mean values and standard deviations: angle 8.7 ± 4.8°, 3D deviation at the implant shoulder 1.62 ± 0.87 mm, mesiodistal deviation 0.87 ± 0.75 mm, buccolingual deviation 0.70 ± 0.66 mm, and apiocoronal deviation 0.95 ± 0.61 mm. The type of jaw had a significant influence on accuracy. Major deviations were observed in the lower jaw. Furthermore, the timing of implant placement influenced the mesiodistal deviation and angular deviation; (4) Conclusions: Freehand implant placement demonstrated a higher level of deviation between the planned and actually achieved implant positions. In particular, the ranges showed a large spread. From a prosthetic point of view, there may be complications during the restoration of the prosthetic crown if the implant exit point is not optimally located or if the implants show a high angular deviation.

Accuracy of static computer-assisted implant placement in long span edentulous area by novice implant clinicians: A cross-sectional in vitro study comparing fully-guided, pilot-guided, and freehand implant placement protocols

BACKGROUND

To ensure accurate implant placement, surgical guides are used to control the steps of implant placement surgery.

PURPOSE

Evaluation of the accuracy of implant placement in long span edentulous area by novice implant clinicians according to fully-guided (FG), pilot-guided (PG), and freehand (FH) placement protocols.

MATERIALS AND METHODS

Maxillary surgical models with four missing teeth from the right first canine to the first molar were produced by 3-dimensional printing. Fourteen clinicians new to implant dentistry participated in the study, and each one of them inserted one canine and one molar implant for every implant placement protocol. All implant placement steps were completed in phantom heads to simulate the clinical situation. To evaluate the accuracy, the implant vertical, horizontal platform, horizontal apex, angle, and interimplant distance deviations from the planned positions were calculated.

RESULTS

With the exception of vertical deviation, the FG placement was clearly more accurate than the PG and FH placements for all the variables for canine and molar implants. The PG placement was significantly more accurate than the FH placement for the horizontal platform and apex deviations, and interimplant distance deviation. The FG placement did not show a significant impact of the location of the implant, or the horizontal deviations of the platform or the apex. The PG and FH placements showed increased deviation at the canine implant than the molar implant, and at the apex of the implants than the platform of the implants.

CONCLUSIONS

Within the limitations of this in vitro study, novice clinicians achieved a significantly more accurate implant position with FG placement, followed by PG and FH placements respectively. Therefore, a form of guided surgery is beneficial for novice clinicians.

Accuracy of Computer-Assisted Dynamic Navigation as a Function of Different Intraoral Reference Systems: An In Vitro Study

The aim of this in vitro study was to determine whether the process chain influences the accuracy of a computer-assisted dynamic navigation procedure. Four different data integration workflows using cone-beam computed tomography (CBCT), conventional impressions, and intraoral digitization with and without reference markers were analyzed. Digital implant planning was conducted using data from the CBCT scans and 3D data of the oral models. The restoration of the free end of the lower jaw was simulated. Fifteen models were each implanted with two new teeth for each process chain. The models were then scanned with scan bodies screwed onto the implants. The deviations between the planned and achieved implant positions were determined. The evaluation of all 120 implants resulted in a mean angular deviation of 2.88 ± 2.03°. The mean 3D deviation at the implant shoulder was 1.53 ± 0.70 mm. No significant differences were found between the implant regions. In contrast, the workflow showed significant differences in various parameters. The position of the reference marker affected the accuracy of the implant position. The in vitro examination showed that precise implantation is possible with the dynamic navigation system used in this study. The results are of the same order of magnitude that can be achieved using static navigation methods. Clinical studies are yet to confirm the results of this study.

Guided-welded approach planning using digital scanning technology for combined screw- and conometric-retained implant-supported maxillary prosthesis

AIM

The goal of this case series was to evaluate the clinical outcome at the 2-year follow-up of immediately loaded combined screw- and conometric-retained implant-supported full-arch restorations virtually planned using digital scanning technology.

MATERIALS AND METHODS

This series included 12 patients presenting hopeless teeth in the maxilla treated with computer-guided flapless implant placement. A total of 72 implants were inserted. All implants were immediately loaded with a complete-arch restoration supported by an intraorally welded framework. Digital scanning technology was used to virtually plan a combined screw and conometric retention of the frameworks. Clinical parameters were assessed at 1 week and at 1, 3, 6, 12, and 24 months follow-up.

RESULTS

The survival rate after 2 years was 98.6%, as one implant failed during the osseointegration period. No major prosthetic complications were observed such as issues with mobility, unscrewed abutments, disconnected conometric copings, and prosthetic fracture. Only one patient registered the chipping of a prosthesis.

CONCLUSION

Based on the results of the present study, the use of combined screw and conometric retention for fixed immediate restorations properly planned using digital scanning technology seems to be a viable treatment alternative to screw or conometric retention alone for immediately loaded rehabilitations.

Methods Used to Assess the 3D Accuracy of Dental Implant Positions in Computer-Guided Implant Placement: A Review

The purpose of this review is to examine various assessment methods in order to compare the accuracy between the virtually planned and clinically achieved implant positions. In this review, comparison methods using pre- and post-operative computed topography (CT) data and digital impressions for definitive prosthesis will be described. The method for the displacement and strain for quantification of the error will also be explored. The difference between the planned and the actual implant placement position in guided implant surgery is expressed as an error. Assessing the accuracy of implant-guided surgery can play an important role as positive feedback in order to reduce errors. All of the assessment methods have their own inevitable errors and require careful interpretation in evaluation.

Immediately restored full arch-fixed prosthesis on implants placed in both healed and fresh extraction sockets after computer-planned flapless guided surgery. A 3-year follow-up study

BACKGROUND

The treatment of patients by the use of immediate implant placement in post-extractive site is a challenging procedure.

PURPOSE

A 3-year clinical and radiological study of post-extractive implants placed using flapless guided surgery and immediately functioning.

MATERIALS AND METHODS

Thirty-two patients (23 females and 9 males), aged between 44 and 73 years (a mean age of 59.5) were treated with immediate full arch restorations and flapless implant surgery in fresh extraction and healed sites. A double-guide technique stent in conjunction with the NobelGuide system (Nobel Biocare AB, Göteborg, Sweden) was used.

RESULTS

A total of 285 implants over 32 patients were assessed. The patients were clinically and radiologically followed for 3 years. One hundred and ninety-five implants were placed in the maxilla and 90 in the mandible. Eight patients received implants in both arches. One hundred and ninety-seven implants were placed in extraction sites (137 maxilla, 60 mandible) and 88 in healed sites (58 maxilla and 30 mandible). The overall cumulative implant survival rate (CISR) was 97.54%. Two implants failed in maxillary healed sites (CISR 96.55%), three in maxillary extraction sites (CISR 97.81%), and two in mandibular extraction sites (CISR 96.66%). No implant failed in healed mandibular sites (CSR 100%). All fixed prostheses maintained stability and good functionality during the follow-up, accounting for a cumulative prosthesis survival rate (CPSR) of 100%. The overall marginal bone level (MBL) was -0.52 mm (SD -0.18) after 6 months, -0.88 mm (SD -0.20) after 12 months, -1.05 mm (SD -0.21) after 24 months, and -1.32 mm (SD -0.41) after 36 months.

CONCLUSIONS

Computer-guided surgery using double-template technique (DTT) shows a predictable outcome in the medium term, decreasing treatment timing and patient discomfort.

Computer-assisted surgery and intraoral welding technique for immediate implant-supported rehabilitation of the edentulous maxilla: case report and technical description

BACKGROUND

Complications are frequently reported when combining computer assisted flapless surgery with an immediate loaded prefabricated prosthesis. The authors have combined computer-assisted surgery with the intraoral welding technique to obtain a precise passive fit of the immediate loading prosthesis.

METHODS

An edentulous maxilla was rehabilitated with four computer assisted implants welded together intraorally and immediately loaded with a provisional restoration.

RESULTS

A perfect passive fit of the metal framework was obtained that enabled proper osseointegration of implants. Computer assisted preoperative planning has been shown to be effective in reducing the intraoperative time of the intraoral welding technique. No complications were observed at 1 year follow-up.

CONCLUSIONS

This guided-welded approach is useful to achieve a passive fit of the provisional prosthesis on the inserted implants the same day as the surgery, reducing intraoperative time with respect to the traditional intraoral welding technique. Copyright © 2015 John Wiley & Sons, Ltd.

Augmented reality-based navigation system for wrist arthroscopy: feasibility

PURPOSE

In video surgery, and more specifically in arthroscopy, one of the major problems is positioning the camera and instruments within the anatomic environment. The concept of computer-guided video surgery has already been used in ear, nose, and throat (ENT), gynecology, and even in hip arthroscopy. These systems, however, rely on optical or mechanical sensors, which turn out to be restricting and cumbersome. The aim of our study was to develop and evaluate the accuracy of a navigation system based on electromagnetic sensors in video surgery.

METHODS

We used an electromagnetic localization device (Aurora, Northern Digital Inc., Ontario, Canada) to track the movements in space of both the camera and the instruments. We have developed a dedicated application in the Python language, using the VTK library for the graphic display and the OpenCV library for camera calibration.

RESULTS

A prototype has been designed and evaluated for wrist arthroscopy. It allows display of the theoretical position of instruments onto the arthroscopic view with useful accuracy.

DISCUSSION

The augmented reality view represents valuable assistance when surgeons want to position the arthroscope or locate their instruments. It makes the maneuver more intuitive, increases comfort, saves time, and enhances concentration.