Comparison of feasibility, time consumption and costs of three virtual planning systems for surgical correction of midfacial deficiency

Do Cone Beam CT Picture Archiving and Communication Systems Viewer Interfaces Meet the Expectations of Dental Professionals From a Usability Perspective?

Background Cone beam computed tomography (CBCT) has revolutionized dental and maxillofacial imaging by providing high-resolution 3D visualizations, essential for accurate diagnosis and treatment planning. Despite its clinical advancements, the usability of CBCT viewer interfaces, which play a crucial role in the effective interpretation of imaging data, remains a critical concern. Objective This study aims to evaluate the usability of a CBCT viewer interface in clinical settings, focusing on the effectiveness, efficiency, and satisfaction perspectives, to identify potential areas for improvement. Methods Twenty-two participants (N=22) were assigned the task of locating the mental foramen in a mandible dataset, selected randomly, using the multiplanar reconstruction (MPR) mode of a CBCT viewer interface on a local network. The task's effectiveness was gauged by the completion rate, while efficiency was measured through the duration of the task, the number of mouse clicks, and the cursor's path in both pixels and meters. Satisfaction or perceived usability was evaluated using the system usability scale (SUS-TR), and computer system usability questionnaire (T-CSUQ), among other scales, with participants also providing open-ended feedback. Demographic characteristics served as classification variables. Results All participants completed the given task. No demography-related differences in efficiency were observed. Perceived usability (SUS-TR: 60.68±19.58, T-CSUQ: 43.63±16.34) was below the industry standards, categorizing the system as a detractor. Commonly reported issues included accessing the MPR window, cursor behavior, and unclear error messages. The mean SUS-TR score negatively correlated with efficiency-related variables (p<0.05 for each). Conclusions The study's findings indicate that the CBCT viewer interface does not fully meet dental professionals' usability expectations, as evidenced by the task's completion rate, efficiency metrics, and below-average usability scores. Despite the successful task completion by all participants, the identified issues in interface design, such as difficulties in accessing the MPR window and unclear error messages, highlight significant areas for improvement. To enhance user satisfaction and efficiency, future developments of CBCT viewer interfaces should incorporate feedback from end-users and prioritize user-friendly design principles.

Virtual surgical planning in craniomaxillofacial surgery: a structured review

Craniomaxillofacial (CMF) surgery is a challenging and very demanding field that involves the treatment of congenital and acquired conditions of the face and head. Due to the complexity of the head and facial region, various tools and techniques were developed and utilized to aid surgical procedures and optimize results. Virtual Surgical Planning (VSP) has revolutionized the way craniomaxillofacial surgeries are planned and executed. It uses 3D imaging computer software to visualize and simulate a surgical procedure. Numerous studies were published on the usage of VSP in craniomaxillofacial surgery. However, the researchers found inconsistency in the previous literature which prompted the development of this review. This paper aims to provide a comprehensive review of the findings of the studies by conducting an integrated approach to synthesize the literature related to the use of VSP in craniomaxillofacial surgery. Twenty-nine related articles were selected as a sample and synthesized thoroughly. These papers were grouped assigning to the four subdisciplines of craniomaxillofacial surgery: orthognathic surgery, reconstructive surgery, trauma surgery and implant surgery. The following variables - treatment time, the accuracy of VSP, clinical outcome, cost, and cost-effectiveness - were also examined. Results revealed that VSP offers advantages in craniomaxillofacial surgery over the traditional method in terms of duration, predictability and clinical outcomes. However, the cost aspect was not discussed in most papers. This structured literature review will thus provide current findings and trends and recommendations for future research on the usage of VSP in craniomaxillofacial surgery.

Surgical Margins in 3D Planned Mandibular Resections for Squamous Cell Carcinomas of the Oral Cavity

PURPOSE

Three-dimensional (3D) planned mandibular resections using cutting guides and preplanned plates are now widely used in oncological surgery. The main advantages are the gain of time, precision, and esthetic outcomes. The drawbacks include costs, time for planning, and printing the surgical tools. This time between the radiological data and the surgery may allow tumor progression, rendering the custom-made guides useless. There is no consensus regarding surgical margins that should be planned to ensure a safe oncologic outcome. The purpose of this retrospective study is to evaluate if the planned bony margins are adequate.

MATERIALS AND METHODS

Inclusion criteria were: Squamous cell carcinomas of the anterior and lateral floor of mouth with mandibular invasion (T4); mandibular resection using 3D planning and cutting guides. Between June 2015 to December 2019, 16 patients met the criteria. The time between the planning and the surgery was recorded. The authors decided to use a margin of at least 1 cm on the preoperative computerized tomography scans on each side of the tumors in our planning for all patients. The authors then measured the distance of the bone resection on the pathological specimen.

RESULTS

All 16 patients had safe bone surgical margins (R0). The average time from the scanners used for the planning to the surgery was 33 days.

DISCUSSION

All the cutting guides could be used. The pathology examination showed safe oncological margins and no patients required further resection. A 1 cm margin during 3D planning for mandibular resections with 3D printed cutting guides, in patients with T4 Squamous Cell Carcinomas can therefore be considered safe.

Use of non-surgical aesthetic refinement after orthognathic surgery: Case studies

Orthognathic surgery has an undeniable functional effect, but the aesthetic result must not be disregarded, especially since many patients visit the surgeon precisely because of an aesthetic complaint and ignore the practical benefits. The aim of this paper is to discuss about an ideal treatment that combines this functional improvement with facial aesthetics and improves it after the operation. In order to predict which aesthetic deficits may occur, a facial analysis is essential. As precise as the virtual planning may be, there is still no exact predictability of soft tissue behavior. Some non-surgical procedures can help the surgeon achieve a result that better meets the patients' expectations. Imaging exams, photographs, facial analyzes, and patient complaints are essential to assess the possibility of any postoperative refinement. The entire surgical planning is discussed with the patient; the possibility of refinement must be part of the treatment plan. The surgeon's focus is on the functional correction of the dentofacial deformity, but the aesthetic outcome is essential for the patient. The results of this study suggest that refinement should be part of the treatment plan.

Accuracy of 3 Soft Tissue Prediction Methods After Double-Jaw Orthognathic Surgery in Class III Patients

PURPOSE

We aimed to evaluate the accuracy and validity of conventional manual prediction method (CM) and 2-dimensional and 3-dimensional (3D) soft tissue prediction methods for Class III bimaxillary orthognathic surgery patients.

METHODS

Twenty skeletal Class III patients were included in this study. Soft tissue prediction was achieved with a traditional manual technique, 2-dimensional software (Dolphin Imaging, version 11.5), and 3-dimensional software (SimPlant Master, version 16.0) on preoperative lateral cephalometric radiographs and cone beam computurized tomography (CBCT) images and then compared with postoperative lateral cephalometric radiographs obtained at least 6 months after surgery (mean, 11.5 ± 6.77 months). Forty-eight measurements were done to determine the reliability of the methods.

RESULTS

All prediction methods have limited postsurgery prediction accuracy for the subnasal upper lip area. Most of the differences were not more than 3 mm for all study groups, except the 3D software, which predicted the upper lip area to be, on average, 3.08 ± 1.38 mm further back (P < 0.001). Although the conventional method predicted 20 of 48 measurements similar to the final results, the poorest predictions were found at the nasal and labiomental areas (P < 0.001). Two-dimensional software predicted 23 of 48 measurements very close to the final results but made significantly different predictions for the nasolabial and labiomental angles, labrale superius point, and the chin area.

CONCLUSIONS

The 3D method predicted, especially the upper lip area, to be significantly and clinically incorrect, and its soft tissue prediction was insufficient compared with the other 2 methods. The 3D software needs to be updated, especially in evaluating soft tissue A point and upper lip changes after surgery.