Is minimally invasive approach to genioplasty predictable for mentolabial soft tissue? A retrospective cohort study.

INTRODUCTION: The aim of this study was to conduct a three-dimensional analysis of the effects on mentolabial soft tissues of three different orthognathic surgery protocols: bimaxillary surgery without genioplasty, bimaxillary surgery with conventional or minimally invasive genioplasty (MIS). MATERIALS AND METHODS: Pre-operative and post-operative CBCT were superimposed to quantify and ascertain the direction of mandibular movements, and soft tissue were analyzed to evaluate the hard to soft tissue ratio. Data from 97 consecutive patients were evaluated: 30 conventional genioplasty, 36 MIS and 31 no genioplasty. RESULTS: The impact of the surgical movements on the overlying soft tissues can be consider with stronger correlation in the group No Genioplasty in the whole mentolabial region, stronger correlation in labial and pogonion region in the MIS group and no stronger correlation in the conventional group. CONCLUSIONS: Sutures in the mentolabial region directly interfere with the postoperative impact of orthognathic surgery on soft tissues in mentolabial area, in both the vertical and horizontal directions. A smaller incision - consequently involving less detachment of soft tissues in the region - may promote a lower risk of chin ptosis, in addition to greater suspension of the musculature.

A simple and free software-based inferior alveolar nerve protector surgical guide in bilateral sagittal split osteotomy.

OBJECTIVES: This technical note introduces a novel concept of a alveolar inferior nerve protector guide during orthognathic surgery based on a free-software creation and printing. TECHNICAL NOTE: Orthognathic surgery using Virtual Surgical Planning software like Dolphin Imaging ® v 11.9 facilitated a bimaxillary procedure with mandible advancement and occlusal plane correction, later followed by 3D printing of splints. The process involved importing a composite skull with osteotomies into Blender ® software, where solids were added and edited to match Dolphin's osteotomies, ensuring bone contact without distortion. The guide creation was performed adhering to bilateral sagittal split osteotomy principles, maintaining precision, resulting in preserved inferior alveolar nerve and faster operation times compared to non-guided procedures, as demonstrated by postoperative CT scans. CONCLUSIONS: Integrating advanced tools like Blender software into maxillofacial surgery represents a significant advancement. Despite challenges like the absence of specific manuals for this purpose in Blender, using such software offers innovative and cost-effective solutions. Developing user-friendly resources tailored to surgical applications such as a protector guide within Blender can enhance its usability and improve surgical outcomes and patient care, leading to groundbreaking advancements in maxillofacial surgery.

Pre-operative virtual three-dimensional planning for proximal humerus fractures: A proof-of-concept study.

Purpose: To (1) evaluate surgeon agreement on plating features (position and screw length) in virtual 3D planning software, (2) describe outcomes (fracture reduction, plate position, malpositioning of calcar screws and screw lengths) of plate fixations planned with routine pre-operative assessment (2D- and 3D CT imaging) and those planned with dedicated virtual 3D software of the same proximal humerus fracture. Methods: Fourteen proximal humerus fractures were retrospectively reduced and fixed with virtual planning software by eight attending orthopaedic surgeons and compared to the true surgical fixation with post-operative computed tomography (CT) scans. Reduction differences were quantified using CT micromotion analysis. Results: Intraclass correlation for screw lengths was 0.97 (95% CI: 0.96-0.98) and 0.90 (95% CI: 0.79-0.96) for plate position. Mean difference in total fracture rotation of the head between the virtual and conventional group was 22.0°. Plate position in the virtual planning group was 3.2 mm more proximal. There were no differences in inferomedial quadrant calcar screw positioning and, apart from the superior posterior converging screw, no significant differences in screw lengths. Conclusion: Reproducibility on plate position and screw length with virtual planning software is adequate. Apart from fracture reduction, virtual planning yielded similar plate positions, screw malpositioning rates and lengths compared to routine pre-operative assessment.

Retrospective analysis of ideal needle puncture angles and depths for temporomandibular joint arthrocentesis using CBCT data.

BACKGROUND: This study aimed to investigate the range of angles and depths necessary for effective entry into the TMJ using CBCT images, focusing on classical Holmlund Hellsing points and a two-needle approach. METHODS: A retrospective cohort of CBCT images from January 2020 to November 2023 was analysed using 3D analysis to determine the variance in the required angles and depths. RESULTS: The average age of the 68 participants included in the study was 29.5 ± 11.1, 58.8% of the participants were female and 41.2% were male. The anterior needle measurements showed a relatively low standard deviation(SD) in depth(SD:3.6) with a low variance coefficient(12.5%), whereas the axial and coronal angles exhibited greater variability(SD:9.1 and 7.6, respectively). For the posterior needles, moderate SDs in depth(SD:3.5) and greater variabilities in axial and coronal angles(SD:9.6 and 5.3, respectively) were observed. A weak negative correlation was observed between the axial angle of the posterior needle and age(p: 0.028, Pearson r: -0.29) Anterior needle depth (p:0.037) and posterior needle axial angle(p:0.014) were greater in males than females. The anterior needle depth in patients with temporamandibular disease was greater than in those without(p:0,03). CONCLUSION: There were significant differences in the angle measurements for both anterior and posterior needles, but lower variance in depth. The depths and angles of the needles did not correlate with age.

Surgical Navigation and CAD-CAM-Designed PEEK Prosthesis for the Surgical Treatment of Facial Intraosseous Vascular Anomalies.

Background: Intraosseous vascular anomalies in the facial skeleton present significant diagnostic and therapeutic challenges due to complex anatomy. These anomalies represent about 0.5-1% of bony neoplastic and tumor-like lesions, usually presenting as a firm, painless mass. Most described intraosseous vascular malformations are venous malformations (VMs) and, more rarely, arteriovenous malformations. Objectives: The objectives of this work are to show our experience, protocol and the applications of computer planning, virtual surgery, CAD-CAM design, surgical navigation, and computer-assisted navigated piezoelectric surgery in the treatment of facial intraosseous vascular anomalies and to evaluate the advantages and disadvantages. Methods: Three females and one male with periorbital intraosseous vascular anomalies were treated using en-block resection and immediate reconstruction with a custom-made PEEK prosthesis. One lesion was in the supraorbital rim and orbital roof, one in the frontal bone and orbital roof, and two in the zygomatic region. We accomplished the resection and reconstruction of the lesion using virtual planning, CAD-CAM design, surgical navigation and piezoelectric device navigation. Results: There were no complications related to the surgery assisted with navigation. With an accuracy of less than 1 mm, the procedure may be carried out in accordance with the surgical plan. The surgeon's degree of uncertainty during deep osteotomies and in locations with low visibility was decreased by the use of the navigated piezoelectric device. Conclusions: Resection and reconstruction of facial intraosseous vascular anomalies benefit from this new surgical strategy using CAD-CAM technologies, computer-assisted navigated piezoelectric surgery, and surgical navigation.

From medical imaging to 3D printed anatomical models: a low-cost, affordable 3D printing approach.

OBJECTIVE: To share our experience in creating precise anatomical models using available open-source software. METHODS: An affordable method is presented, where from a DICOM format of a computed tomography, a segmentation of the region of interest is achieved. The image is then processed for surface improvement and the DICOM format is converted to STL. Error correction is achieved and the model is optimized to be printed by stereolithography with a desktop 3D printer. RESULTS: Precise measurements of the dimensions of the DICOM file (CT), the STL file, and the printed model (3D) were carried out. For the C6 vertebra, the dimensions of the horizontal axis were 55.3 mm (CT), 55.337 mm (STL), and 55.3183 mm (3D). The dimensions of the vertebral body were 14.2 mm (CT), 14.551 mm (STL), and 14.8159 mm (3D). The length of the spinous process was 18.2 mm (CT), 18.283 mm (STL), and 18.2266 mm (3D), while its width was 8.5 mm (CT), 8.3644 mm (STL), and 8.3226 mm (3D). For the C7 vertebra, the dimensions of the horizontal axis were 58.6 mm (CT), 58.739 mm (STL), and 58.7144 mm (3D). The dimensions of the vertebral body were 14 mm (CT), 14.0255 mm (STL), and 14.2312 mm (3D). The length of the spinous process was 18.7 mm (CT), 18.79 mm (STL), and 18.6458 mm (3D), and its width was 8.9 mm (CT), 8.988 mm (STL), and 8.9760 mm (3D). CONCLUSION: The printing of a 3D model of bone tissue using this algorithm is a viable, useful option with high precision.

OBJETIVO: Compartir nuestra experiencia para crear modelos anatómicos precisos utilizando software con licencia abierta disponibles. MÉTODOS: Se presenta un método asequible, en donde a partir de un formato DICOM de una tomografía computarizada se logra una segmentación de la región de interés. Posteriormente se procesa la imagen para una mejora de superficie y se realiza la conversión de formato DICOM a STL. Se logra la corrección de errores y se optimiza el modelo para luego ser impreso por medio de estereolitografía con una impresora 3D de escritorio. RESULTADOS: Se efectuaron mediciones precisas de las dimensiones del archivo DICOM (TC), del archivo STL y del modelo impreso (3D). Para la vértebra C6, las dimensiones del eje horizontal fueron 55.3 mm (TC), 55.337 mm (STL) y 55.3183 mm (3D). Las dimensiones del cuerpo vertebral fueron 14.2 mm (TC), 14.551 mm (STL) y 14.8159 mm (3D). La longitud de la apófisis espinosa fue de 18.2 mm (TC), 18.283 mm (STL) y 18.2266 mm (3D), mientras que su ancho fue de 8.5 mm (TC), 8.3644 mm (STL) y 8.3226 mm (3D). Para la vértebra C7, las dimensiones del eje horizontal fueron 58.6 mm (TC), 58.739 mm (STL) y 58.7144 mm (3D). Las dimensiones del cuerpo vertebral fueron 14 mm (TC), 14.0255 mm (STL) y 14.2312 mm (3D). La longitud de la apófisis espinosa fue de 18.7 mm (TC), 18.79 mm (STL) y 18.6458 mm (3D), y su ancho fue de 8.9 mm (TC), 8.988 mm (STL) y 8.9760 mm (3D). CONCLUSIÓN: La impresión de un modelo en 3D de tejido óseo mediante este algoritmo resulta una opción viable, útil y con una alta precisión.

Digital Implant-Supported Restoration Planning Placed in Autologous Graft Using Titanium Implants Produced by Additive Manufacturing.

This clinical report presents a technique to reconstruct extensively resected mandibles using a combination of autologous bone grafts and additive manufacturing techniques. Mandibular defects, often arising from trauma, tumors, or congenital anomalies, can severely impact both function and aesthetics. Conventional reconstruction methods have their limitations, often resulting in suboptimal outcomes. In these reports, we detail clinical cases where patients with different mandibular defects underwent reconstructive surgery. In each instance, autologous grafts were harvested to ensure the restoration of native bone tissue, while advanced virtual planning techniques were employed for precise graft design and dental implant placement. The patients experienced substantial improvements in masticatory function, speech, and facial aesthetics. Utilizing autologous grafts minimized the risk of rejection and complications associated with foreign materials. The integration of virtual planning precision allowed customized solutions, reducing surgical duration and optimizing implant positioning. These 2 cases underscores the potential of combining autologous grafts with virtual planning precision and dental implants produced by additive manufacturing for mandible reconstruction.

Advanced outcomes of mixed reality usage in orthognathic surgery: a systematic review.

INTRODUCTION: Orthognathic surgery (OGS) is a highly sophisticated surgical technique that aims to repair a variety of skeletal and dental abnormalities, including misaligned jaws and teeth. It requires precise preoperative preparation and advanced surgical skills, which are typically learned through years of practical experience in operating rooms or laboratory-based surgical training facilities utilizing cadavers or models. The traditional physical hands-on method of surgical training is still used at OGS. However, this method requires a longer time of preparation. Currently, mixed reality (MR)-a combination of virtual reality and augmented reality technology-is an innovation of OGS. The present study aimed to present a comprehensive review of studies that assessed the advantages of utilizing mixed reality technology in OGS. METHODS: A modified Population, Intervention, Comparison, Outcome strategy was performed using a combination of electronic (PubMed, Cochrane, Embase) and manual searches between 2013 and 2023 exploring mixed reality (MR) technology in OGS in the last 10 years. The inclusion criteria were limited to the patient and study model focusing on the clinical application of MR and the associated field of OGS. RESULT: The initial search indicated 1731 studies, of which 17 studies were included for analysis. The main results indicated that the use of MR technology in OGS led to high accuracy and time reduction as primary outcomes and cost-effectiveness and skill improvement as secondary outcomes. The review firmly concluded that MR technology exhibited a positive impact on students, trainees, and oromaxillofacial surgeons. However, due to the heterogeneity of the included studies, meta-analyses could not be performed. Collectively, these findings provide strong evidence for the advantages of MR technology in orthognathic surgery. CONCLUSION: MR technology significantly improves OGS planning efficiency by providing pre-surgical information and serving as an intraoperative navigation tool, reducing surgical time without compromising outcomes. Virtual training using MR technology exerts a positive impact on knowledge and skill improvement for OGS. This innovative technology will revolutionize the healthcare system and enhance patient care.

Computer-assisted open exposure of palatally impacted canines for orthodontic eruption: A randomized clinical trial.

OBJECTIVE: This randomized clinical trial aimed to assess the feasibility of computer-assisted open exposure of palatally impacted canines. MATERIALS AND METHODS: Patients aged 11-30 years who required orthodontic eruption for the full palatal impaction of their canines were included in this study. Exclusion criteria were psychosocial and dental contraindications of orthodontic treatment, congenital craniofacial disorders, and trauma in the patient's history in the vicinity of the surgical site. Virtual planning software was used to register the intraoral scans and cone-beam computed tomography data and to design a surgical template. In the test group, exposure of the canines was guided by a surgical template, whereas in the control group, the surgeon relied on the surgical plan to localize the impacted canine. The success of the intervention, duration of surgery, and complications, including excessive hemorrhage, damage to the canine or neighboring anatomical landmarks, and postoperative inflammation of the surgical site were assessed. Postoperative pain was reported by the patients using the visual analog pain scale (VAS). RESULTS: Surgery was deemed successful in all patients in both groups. During healing, no complications were observed. The duration of surgery decreased significantly in the test group (4 min 45.1 s ± 1 min 8.4 s) compared to that in the control group (7 min 22.3 s ± 56.02 s). No statistically significant differences were observed between the VAS scores of the two study groups. CONCLUSIONS: The application of virtual planning and static navigation is a viable approach for the open exposure of palatally impacted canines. CLINICAL TRIAL REGISTRATION NUMBER: NCT05909254. CLINICAL SIGNIFICANCE: Computer-assisted surgery is a feasible method for open exposure of palatally impacted canines, which decreases the duration of surgery compared to the freehand method.

Digital resources for surgical and restorative treatment of excessive gingival display in one session.

OBJECTIVE: This article aims to showcase the implementation of a digital workflow in addressing a case of multifactorial excessive gingival display in a patient with high esthetic demands, incorporating both surgical and restorative interventions in a single session. CLINICAL CONSIDERATIONS: A 28-year-old female patient presented with excessive gingival display, attributed to a combination of short teeth due to altered passive eruption, lip hyperactivity, and a sub-nasal depression that lodged the upper lip during spontaneous smiling. The multidisciplinary treatment strategy encompassed surgical crown lengthening, the placement of a biovolume in the maxillary concavity, and the rehabilitation of the six anterior teeth with direct composite resin, all done in a single session. Smilecloud Biometrics was used to digitally plan the smile, and the final wax-up/mock-up was approved by the patient prior to any irreversible procedure. A digital planning center (GuiderLab) enabled the materialization of the virtual planning and the printing of the periodontal surgical guide, the biovolume, and the resin layering guides for the restorative technique. CONCLUSIONS: Adopting a digital workflow in multidisciplinary cases with excessive gingival display leads to predictable and more expedited outcomes, ensuring a favorable result between soft and hard tissues. CLINICAL SIGNIFICANCE: Excessive gingival display is a condition with multifactorial etiologies, including dentoalveolar, periodontal, skeletal, or muscular origins, or a combination of these factors. The diagnoses of altered passive eruption and a hypermobile upper lip are common in daily clinical practice and can be successfully managed through surgical crown lengthening and filling of the maxillary concavity, respectively. To achieve the desired outcome, restorative procedures often complement these surgical interventions.

Symmetry of the left and right tibial plafond; a comparison of 75 distal tibia pairs.

PURPOSE: Tibia plafond or pilon fractures present a high level of complexity, making their surgical management challenging. Three-Dimensional Virtual Planning (3DVP) can assist in preoperative planning to achieve optimal fracture reduction. This study aimed to assess the symmetry of the left and right tibial plafond and whether left-right mirroring can reliably be used. METHODS: Bilateral CT scans of the lower limbs of 75 patients without ankle problems or prior fractures of the lower limb were included. The CT images were segmented to create 3D surface models of the tibia. Subsequently, the left tibial models were mirrored and superimposed onto the right tibia models using a Coherent Point Drift surface matching algorithm. The tibias were then cut to create bone models of the distal tibia with a height of 30 mm, and correspondence points were established. The Euclidean distance was calculated between correspondence points and visualized in a boxplot and heatmaps. The articulating surface was selected as a region of interest. RESULTS: The median left-right difference was 0.57 mm (IQR, 0.38 - 0.85 mm) of the entire tibial plafond and 0.53 mm (IQR, 0.37 - 0.76 mm) of the articulating surface. The area with the greatest left-right differences were the medial malleoli and the anterior tubercle of the tibial plafond. CONCLUSION: The tibial plafond exhibits a high degree of bilateral symmetry. Therefore, the mirrored unfractured tibial plafond may be used as a template to optimize preoperative surgical reduction using 3DVP techniques in patients with pilon fractures.

Avoiding Sinus Floor Elevation by Placing a Palatally Angled Implant: A Morphological Study Using Cross-Sectional Analysis Determined by CBCT.

BACKGROUNDS: Tooth loss in the posterior maxilla often necessitates dental implant placement, but the maxillary sinus anatomy poses challenges, especially during sinus floor elevation. Mesially angled implants are an alternative for total edentulism, but for single tooth deficiencies, palatally angled implants may offer a solution. This study evaluates the prevalence of avoiding sinus floor elevation by placing palatally angled implants in cases with a single missing tooth. METHODS: A retrospective study at Ahmet Kelesoglu Faculty of Dentistry involved 100 participants with a single missing tooth and prior CBCT scans. Virtual implants were placed using OnDemand3D (version 1.0.7462) software. On CBCT sections, implants were angled palatally to avoid sinus or nasal cavity perforation. Statistical analysis was conducted using R and MedCalc (version 4.3.2) software. RESULTS: Of the participants (60% female, average age 50.45), 76 edentulous regions required sinus elevation. The implant placeability rates varied across zones (second molar: 39.3%, first molar: 63.1%, second premolar: 78.5%). Implant placement at a palatal angle was significantly higher in the second premolar and first molar regions. Statistically significant differences were observed in the implant placeability between regions. CONCLUSIONS: This study supports the feasibility of avoiding sinus floor elevation through palatally angled implants in specific cases, reducing the associated complications.

Advancements in computer-assisted orthognathic surgery: A comprehensive review and clinical application in South Korea.

OBJECTIVES: Orthognathic surgery (OS) has evolved with technological advancements, notably through the implementation of computer-assisted orthognathic surgery (CAOS). This article aims to elucidate various types of CAOS and their efficiency and accuracy, supplemented by a thorough literature review focusing on their clinical applications in South Korea. STUDY SELECTION, DATA, AND SOURCES: A comprehensive search strategy was employed, including systematic reviews, meta-analyses, randomized controlled trials, and observational studies published until December 2023 in the PubMed, MEDLINE, and Google Scholar databases. The literature search was limited to articles written in English. RESULTS: Static CAOS demonstrated high precision, reduced operative time, and high accuracy, suggesting its potential reliability in orthognathic procedures. Dynamic CAOS presented a promising avenue for exploration, showing an accuracy comparable to that of traditional methods. The critical considerations for CAOS include accuracy, time efficiency, and cost-effectiveness. Recent studies have indicated advancements in the time efficiency of static CAOS. Static CAOS requires less equipment and is more cost-effective than dynamic CAOS. CONCLUSIONS: CAOS offers clear advantages over conventional OS in terms of surgical convenience and accuracy in implementing the surgical plan. To achieve recognition as the gold standard method for maxillofacial deformity treatment, CAOS must overcome its limitations and undergo continuous verification via well-designed studies. CLINICAL SIGNIFICANCE: The introduction of CAOS, mainly static CAOS with high precision and reduced surgical time, signifies a notable advancement in OS. However, rigorous studies are warranted to validate CAOS as the gold standard for treating maxillofacial deformities.

Shaping the 4D frontier in maxillofacial surgery with faceMesh evolution.

OBJECTIVES: This work aims to introduce a Python-based algorithm and delve into the recent paradigm shift in Maxillofacial Surgery propelled by technological advancement. The provided code exemplifies the utilization of the MediaPipe library, created by Google in C++, with an additional Python interface available as a binding. TECHNICAL NOTE: The advent of FaceMesh coupled with artificial intelligence (AI), has brought about a transformative wave in contemporary maxillofacial surgery. This cutting-edge deep neural network, seamlessly integrated with Virtual Surgical Planning (VSP), offers surgeons precise 4D facial mapping capabilities. It accurately identifies facial landmarks, tailoring surgical interventions to individual patients, and streamlining the overall surgical procedure. CONCLUSION: FaceMesh emerges as a revolutionary tool in modern maxillofacial surgery. This deep neural network empowers surgeons with detailed insights into facial morphology, aiding in personalized interventions and optimizing surgical outcomes. The real-time assessment of facial dynamics contributes to improved aesthetic and functional results, particularly in complex cases like facial asymmetries or reconstructions. Additionally, FaceMesh has the potential for early detection of medical conditions and disease prediction, further enhancing patient care. Ongoing refinement and validation are essential to address limitations and ensure the reliability and effectiveness of FaceMesh in clinical settings.

[Virtual preoperative planning and 3D-printed templates for pre-contoured plates in treatment of acetabular posterior wall fractures].

OBJECTIVE: To evaluate the feasibility and accuracy of virtual preoperative planning and 3D-printed templates for pre-contoured plates for the treatment of posterior wall fractures of the acetabulum. METHODS: A retrospective analysis of 29 patients with posterior acetabular wall fractures treated between August 2017 and March 2021 were divided into 2 groups based on whether to use preoperative virtual planning and 3D printed template. In 3D-printing group, there were 14 patients, including 10 males and 4 females； aged from 21 to 53 years old；CT-based virtual surgical planning was done using Mimics and 3-Matic software and 3D-printed templates for pre-contoured plates were adopted. In conventional group, there were 15 patients, including 10 males and 5 females；aged from 19 to 55 years old；conventional method of intra-operative contouring to adapt the plate to the fracture region was adopted. Blood loss, surgical time, radiographic quality of reduction, and hip function were compared between groups. RESULTS: The difference in operation time and intraoperative blood loss was significant（P<0.05）. Twenty-three patients were followed up from 12 to 30 months, and the fractures in both groups healed with a healing time of 3 to 6 months. At the last follow-up, the Merle d'Aubign-Postel score of the 3D printed group was lower than that of the conventional group（P<0.05）, with no significant differences in walking ability, hip mobility and total score（P>0.05）. In 3D printing group, 6 cases were excellent, 5 cases were good, 3 cases were fair；in conventional group, 5 cases were excellent, 5 cases were good, 4 cases were fair, 1 case was worse；no significant difference between two groups（P>0.05）. CONCLUSION: Virtual preoperative planning and 3D-printed templates for pre-contoured plates can reduce operative time and the blood loss of surgery, improve the quality of reduction. This method is efficient, accurate and reliable to treat acetabular posterior wall fractures.

Immediate implant placement in the anterior mandible: a cone beam computed tomography study.

BACKGROUND: The placement of implants into the alveolar socket right after tooth extraction is called immediate implant placement (IIP). This approach has its particularities depending on which region of the jaws is involved. The anterior mandible region is peculiar due to the presence of mandibular incisors, which have the shortest roots among all permanent teeth. PURPOSE: This study aimed to investigate the factors that could be associated with the risk of either cortical bone wall perforation or invasion of the 2 mm secure distance from the surrounding anatomical structures (defined as unsafe implant placement), with IIP in the maxillary aesthetic zone, in a cone-beam computed tomography (CBCT) virtual study. MATERIALS AND METHODS: CBCT exams from 239 eligible subjects were investigated. Implants were virtually placed in two distinct positions: prosthetically-driven (along the long axis of the existing tooth) and bone-driven position (according to the available bone and with regard to nearby anatomical structures). Correlation between several variables was tested, and binary logistic regression analysis in order to assess of the possible associations between covariates and unsafe placement was performed. RESULTS: Safe placing implants was significantly higher for the bone-driven in comparison to the prosthetically-driven position (22.2% vs. 3.3%, respectively), and the 2-mm secure distance from anatomical structures was not possible to respect in the majority of cases (77.6% vs. 82.9%, respectively). Covariates associated with a higher risk of unsafe placement were tooth region (CI in relation to IL and CA), decrease of labial concavity angle (LCA), decrease of mandible basal bone height (MBBH), and decrease in mandibular bone thickness at the tooth apex level (MBT0). CONCLUSION: The possibility of safely placing immediate implants in the anterior mandible is significantly higher for bone-driven than in prosthetically driven position. Presurgical virtual planning with CBCT is a great tool for minimizing the risk of implant unsafe placement with regards to the anatomical conditions in the mandible.

The Accuracy of Guided Implant Surgery With Different Fields of View of Cone-Beam Computerized Tomography.

Although a smaller size field of view (FOV) of cone-beam computerized tomography (CBCT) reduces radiation exposure, its effect on the accuracy of static computer-aided implant surgery (s-CAIS) remains unknown. This study aimed to evaluate the impact of the size of FOV on the accuracy of s-CAIS and to investigate if the arch affects this effect. A total of 32 implant sites on 8 identical scannable models (maxillae and mandibles) were randomly allocated to 2 FOV sizes: test (5 × 5 cm) and control (10 × 10 cm). All models were scanned with an intraoral scanner (IOS). With the registration of the surface scan and CBCT image, a prosthetic-driven implant position was planned. Following the fabrication of surgical templates, a single-blinded surgeon placed all implants with the fully guided s-CAIS protocol. IOS captured the implant positions with the scan body attached. Implant-planning software measured the angular deviation, 3-dimensional (3D) deviation at the crest, and 3D deviation at the apex between preplanned and actual implant positions. Two-way analysis of variance was used to analyze the effect of FOV and arch on the deviations. The size of FOV did not show a significant effect (P > .198) on angular deviation, 3D deviation at the crest, or 3D deviation at the apex. No significant difference was found when comparing the effect of the size of FOV between the maxillary and mandibular implants. In conclusion, the use of small FOV CBCT demonstrated comparable accuracy of s-CAIS to the use of medium FOV CBCT.

Virtual planning, guided surgery, and digital prosthodontics in the treatment of extended mandible chondrosarcoma.

Chondrosarcoma is among the most common primary bone tumors in adults. In the mandible, chondrosarcoma is a very uncommon malignant cartilage-producing tumor. This case report shows how virtual planning combined with other digital technologies may improve masticatory function rehabilitation in patients with enlarged mandibular chondrosarcoma. The present study reports a case of a 52-year-old male patient who was initially diagnosed with a mandible chondroma, which was successfully excised with no evidence of malignant transformation. Nevertheless, the patient's symptoms recurred after 10 years, and a subsequent diagnosis of mandible chondrosarcoma was established, prompting the need for subtotal mandible resection and reconstruction with a fibula-free flap. Following a healing period, the patient underwent dental implant surgery to restore the mandibular dental arch, which was performed utilizing computer-aided design and computer-aided manufacturing technology, with fully guided implant placement facilitated by virtual planning. In this case report, the implant position data merging process is described from the digital impression and control model to ensure optimal passive fit of the full-arch zirconia prosthesis and discuss the importance of occlusal adjustments to avoid technical and biological complications. Virtual planning and digital technologies are crucial for the effective management of mandibular defects, allowing for accurate treatment and complete restoration of mandibular function. Their use leads to improved patient outcomes and quality of life. As technology advances, their importance in treating complex medical conditions is only expected to grow.

Optimizing Orthognathic Surgery: Leveraging the Average Skull as a Dynamic Template for Surgical Simulation and Planning in 30 Patient Cases.

Virtual planning has revolutionized orthognathic surgery (OGS), marking a significant advancement in the field. This study aims to showcase the practical application of our established 3D average skull template as a guiding framework for surgical planning, and to share valuable insights from our clinical experience. We enrolled 30 consecutive Taiwanese patients (18 females and 12 males) who underwent two-jaw orthognathic surgery with surgical simulation, utilizing the average skull template for planning. Results indicate the method's applicability and precision. By adhering to the surgical plan, post-operative outcomes closely aligned with the average skull template, showing negligible deviations of less than 2 mm. Moreover, patients expressed high satisfaction with post-surgery facial changes, with the chin appearance receiving the highest satisfaction scores, while the lowest scores were attributed to nose appearance. Notably, the substantial change in lower jaw position post-mandibular setback surgery contributed to increased satisfaction with the chin position. In conclusion, this study does not seek to replace established surgical planning methods, but underscores that utilizing an average skull as a surgical design template provides a viable, accurate, and efficient option for OGS patients.

Assessment of CAD/CAM Customized V Pattern Plate Versus Standard Miniplates Fixation in Mandibular Angle Fracture (Randomized Clinical Trial).

Background: Mandibular angle is the most common site for fractures, accounting for 23-42% of all cases of mandibular fractures. A customized fixation system is designed directly for a specific patient, which reduces the time spent bending and fixing the plate during the operation. This study was designed to assess the effect of CAD/CAM customized V pattern plate versus standard miniplates fixation in mandibular angle fracture. Materials and Methods: This prospective randomized clinical trial included 26 patients suffering from mandibular angle fracture. Patients were selected from Oral and Maxillofacial Surgery Department, Faculty of Dentistry, Cairo University and Ahmed Maher Teaching Hospital. Study group (13) needed open reduction and internal fixation by using CAD/CAM V plate with surgical guide, while control group (13) needed open reduction and internal fixation by using standard superior-inferior miniplate fixation. The patients were then followed up for one year postoperatively. Results: It showed that there was a statistical difference between the study group and the control group regarding postoperative pain, occlusion, and maximal interincisal opening (p value < 0.05%). There was no statistical difference (p value > 0.05%) in the postoperative panoramic radiograph that was taken within the postoperative 1st week in both groups, while the increase in mean bone density was statistically significant (p value < 0.05%) from 6 months to one year postoperatively. Conclusion: CAD/CAM customized V pattern plate is a suitable plate design because it offers sufficient stability for normal bone healing, the creation of an ideal occlusion, an early return to function, and adequate postoperative radiographic outcomes. Trial Registration: It was registered at ClinicalTrials.gov. Registration number: NCT03761524. Registration date: 03.12.2018.