Computer-Assisted Dental Implant Placement Following Free Flap Reconstruction: Virtual Planning, CAD/CAM Templates, Dynamic Navigation and Augmented Reality

Multidisciplinary Approach to Mandibular Ameloblastoma: A Case Report on Surgical and Prosthetic Management

BACKGROUND Ameloblastoma is a locally aggressive, benign, odontogenic tumor. Reports suggest that the chances of recurrence of this tumor are high if treated with a conservative approach. Concordantly, surgical removal of the lesion along with the affected adjacent tissues and bone structure is recommended to reduce the chances of recurrence. Post-surgical prosthetic rehabilitation is advised to improve speech, mastication, and aesthetic appearance. This case report highlights the treatment and reconstruction challenges that maxillofacial surgeons and their teams face in managing cases of large ameloblastoma. CASE REPORT A 41-year-old Sudani man was referred for the management of a large ameloblastoma associated with the left border of the mandible. Management consisted of surgical removal of the affected mandible along with prosthetically preserving the mandible with grafts and screws. Histopathological, computed tomography, and incisional biopsy evaluation confirmed the presence of ameloblastoma. Postoperatively, no complications were reported. Six months postoperatively, no sign of recurrence was seen. The patient was referred to a surgeon for placement of an endosseous implant. CONCLUSIONS When dealing with large ameloblastoma, an interdisciplinary dental team is essential for improving the treatment results. This case highlights the importance of precise and timely primary care diagnosis and a collaborative approach to treatment. By embracing advancements in digital technologies, surgeons can enhance functional and aesthetic results, improving long-term quality of life.

The Accuracy of Dental Implant Placement With Different Methods of Computer-Assisted Implant Surgery: A Network Meta-Analysis of Clinical Studies

OBJECTIVE

Computer-assisted implant surgery (CAIS) has been introduced as a tool to aid in reaching a more accurate implant position. The aim of this network meta-analysis was to compare all the available CAIS techniques and obtain collective evidence on the method that offers the highest accuracy compared to freehand implant placement.

MATERIALS AND METHODS

Database search was done in PubMed, Scopus, and Cochrane library in addition to extensive search in the gray literature and related systematic reviews, aiming to find clinical studies that compared any CAIS technique with another, or with freehand implant placement. The outcomes evaluated were angle, platform, and apex deviation. The search process ended on March 18, 2024.

RESULTS

Thirty-three studies were included. All CAIS techniques (static with partial or full guidance, dynamic with partial or full guidance, the combination of static and dynamic CAIS) showed significantly less deviation than freehand implant placement, except for the static CAIS with guidance for the pilot drill only. The combination of static and dynamic CAIS ranked best among all other methods. Based on the GRADE system, the certainty of evidence in the outcomes of the meta-analysis was judged as low or moderate.

CONCLUSIONS

The current study demonstrates that computer-assisted implant surgery provides significantly higher accuracy in implant placement, with the combination of static and dynamic CAIS being the most precise. Nevertheless, future studies are needed, considering the different types, locations, and extents of edentulism in the analyzed investigations, as well as the necessity of obtaining stronger evidence.

TRIAL REGISTRATION

PROSPERIO number: CRD42023482030.

Recent Advances in Digital Technology in Implant Dentistry

Digital technology has emerged as a transformative tool in dental implantation, profoundly enhancing accuracy and effectiveness across multiple facets, such as diagnosis, preoperative treatment planning, surgical procedures, and restoration delivery. The multiple integration of radiographic data and intraoral data, sometimes with facial scan data or electronic facebow through virtual planning software, enables comprehensive 3-dimensional visualization of the hard and soft tissue and the position of future restoration, resulting in heightened diagnostic precision. In virtual surgery design, the incorporation of both prosthetic arrangement and individual anatomical details enables the virtual execution of critical procedures (e.g., implant placement, extended applications, etc.) through analysis of cross-sectional images and the reconstruction of 3-dimensional surface models. After verification, the utilization of digital technology including templates, navigation, combined techniques, and implant robots achieved seamless transfer of the virtual treatment plan to the actual surgical sites, ultimately leading to enhanced surgical outcomes with highly improved accuracy. In restoration delivery, digital techniques for impression, shade matching, and prosthesis fabrication have advanced, enabling seamless digital data conversion and efficient communication among clinicians and technicians. Compared with clinical medicine, artificial intelligence (AI) technology in dental implantology primarily focuses on diagnosis and prediction. AI-supported preoperative planning and surgery remain in developmental phases, impeded by the complexity of clinical cases and ethical considerations, thereby constraining widespread adoption.

Prosthetic rehabilitation in patients with jaw reconstruction by fibula free flap: A systematic review

This systematic review aimed to evaluate the dental prosthetic rehabilitation (DPR) in patients after jaw reconstruction with fibula free flap. Four databases were searched from January 2000 to January 2023. Of the 2507 studies identified, 36 observational studies were included. Cancer was the most common surgical indications for jawbone resection with 58.3 % of cases followed by benign tumours which representing 24 %. The DPR rate was estimated at 51.6 % across the studies (ranging from 38 % to 55 % depending on the benign or malignant nature of the tumors). Implant-supported prostheses represented 58.9 % of cases of which 66.9 % were fixed and 33.1 % were implant-stabilized overdentures. Virtual surgical planning (VSP) was used in 20 % of studies and aimed to improve the position of the grafted fibula, quality, and aesthetics of DPR and to decrease ischemia and the operating time. One in two authors performed DPR 12 months after jaw reconstruction. If implant survival rate reached 93 % in non-irradiated fibula, it fell to 38 %, 55 %, and 77 % if implantation occurred in the 12, 17, and 24 months after radiotherapy, respectively. Various parameters should be better investigated in further studies including the typology of the prostheses (implant-supported vs removable), the use of VSP, and the optimal time for DPR taking into account the characteristics of the tumor, the size of bone defect, and the need for external irradiation therapy.

A novel mixed reality-guided dental implant placement navigation system based on virtual-actual registration

BACKGROUNDS

The key to successful dental implant surgery is to place the implants accurately along the pre-operative planned paths. The application of surgical navigation systems can significantly improve the safety and accuracy of implantation. However, the frequent shift of the views of the surgeon between the surgical site and the computer screen causes troubles, which is expected to be solved by the introduction of mixed-reality technology through the wearing of HoloLens devices by enabling the alignment of the virtual three-dimensional (3D) image with the actual surgical site in the same field of view.

METHODS

This study utilized mixed reality technology to enhance dental implant surgery navigation. Our first step was reconstructing a virtual 3D model from pre-operative cone-beam CT (CBCT) images. We then obtained the relative position between objects using the navigation device and HoloLens camera. Via the algorithms of virtual-actual registration, the transformation matrixes between the HoloLens devices and the navigation tracker were acquired through the HoloLens-tracker registration, and the transformation matrixes between the virtual model and the patient phantom through the image-phantom registration. In addition, the algorithm of surgical drill calibration assisted in acquiring transformation matrixes between the surgical drill and the patient phantom. These algorithms allow real-time tracking of the surgical drill's location and orientation relative to the patient phantom under the navigation device. With the aid of the HoloLens 2, virtual 3D images and actual patient phantoms can be aligned accurately, providing surgeons with a clear visualization of the implant path.

RESULTS

Phantom experiments were conducted using 30 patient phantoms, with a total of 102 dental implants inserted. Comparisons between the actual implant paths and the pre-operatively planned implant paths showed that our system achieved a coronal deviation of 1.507 ± 0.155 mm, an apical deviation of 1.542 ± 0.143 mm, and an angular deviation of 3.468 ± 0.339°. The deviation was not significantly different from that of the navigation-guided dental implant placement but better than the freehand dental implant placement.

CONCLUSION

Our proposed system realizes the integration of the pre-operative planned dental implant paths and the patient phantom, which helps surgeons achieve adequate accuracy in traditional dental implant surgery. Furthermore, this system is expected to be applicable to animal and cadaveric experiments in further studies.

A retrospective study on application of fibula/iliac flap surgical techniques to mandibular defects

This study group consists of a total of 61 patients who underwent fibula flap and iliac flap surgeries to repair mandibular defects. Patients' Quality Of life (QOL) at 6 and 24 months after surgery is investigated and compared by the EORTC-QLQ-H&N and OHIP-14. The base data of the two groups of patients are collected and analysed by the SPSS 20.0 statistical software. Independent sample t test was conducted for EORTC-QLQ-H&N and OHIP-14 scores at two time points in each group. The 61 cases of free flap all survived and the difference in the location of the primary tumor between the two groups is statistically significant. The EORTC-QLQ-H&N showed that the score of speech, diet, social contact, and teeth all went up at 6 months after surgery, but went down dramatically at 24 months after surgery. The OHIP-14 showed that there was significant reduction in functional limitation at 24 months after surgery, with statistical significance (p < 0.05) between the groups of iliac flap (19.16 ± 5.33) and fibula flap (33.77 ± 7.71). Therefore, it is suggested that patients suffering from mandibular defects receive surgery utilizing the iliac flap, while those with a larger range of defects or lesions involving the condyle and chin should receive corrective surgery utilizing the fibular flap.

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.

Learning Curve and Comparison of Dynamic Implant Placement Accuracy Using a Navigation System in Young Professionals

The aim of the current study was to evaluate the learning curve and accuracy of implant placement by young professionals using a dynamic computer-assisted surgical system for dental implant placement. Ten students tried to place eight implants with a dynamic surgical system in predefined positions on two consecutive weekends, resulting in 160 implant placements in total. Postoperatively, the positions of the implants were scanned with an intraoral scanner and compared for deviations at the entry point, the apex, as well as angular deviations to the master model. The mean values of all measurements improved; statistical significance was found for the changes in the angle as well as for the position of the implants to the apex (p < 0.001). Furthermore, the young professionals indicated subjective improvement in handling the dynamic surgery system. Navigated surgical dental implant placement can be learned quickly and can support young professionals in everyday clinical practice, especially in difficult anatomic situations.

Current Trends in the Reconstruction and Rehabilitation of Jaw following Ablative Surgery

Simple Summary

The Maxilla and mandible provide skeletal support for of the middle and lower third of our faces, allowing for the normal functioning of breathing, chewing, swallowing, and speech. The ablative surgery of jaws in the past often led to serious disfigurement and disruption in form and function. However, with recent strides made in computer-assisted surgery and patient-specific implants, the individual functional reconstruction of the jaw is evolving rapidly and the prompt rehabilitation of both the masticatory function and aesthetics after jaw resection has been made possible. In the present review, the recent advancements in jaw reconstruction technology and future perspectives will be discussed.

Abstract

The reconstruction and rehabilitation of jaws following ablative surgery have been transformed in recent years by the development of computer-assisted surgery and virtual surgical planning. In this narrative literature review, we aim to discuss the current state-of-the-art jaw reconstruction, and to preview the potential future developments. The application of patient-specific implants and the “jaw-in-a-day technique” have made the fast restoration of jaws’ function and aesthetics possible. The improved efficiency of primary reconstructive surgery allows for the rehabilitation of neurosensory function following ablative surgery. Currently, a great deal of research has been conducted on augmented/mixed reality, artificial intelligence, virtual surgical planning for soft tissue reconstruction, and the rehabilitation of the stomatognathic system. This will lead to an even more exciting future for the functional reconstruction and rehabilitation of the jaw following ablative surgery.