Clinical application of automated virtual orbital reconstruction for orbital fracture management with patient-specific implants: A prospective comparative study.

The aim of the study was to compare automated and manually conducted (slice-by-slice) virtual orbital wall reconstruction in terms of PSI design, manufacture, and clinical application for orbital fracture management. Patients with orbital wall fractures were evaluated for the potential for treatment with PSI, based on automated virtual wall reconstruction; these formed the main group. The surgical outcomes of these main-group patients' treatments were compared with those of the control group, which comprised patients randomly selected for this study, each of whom had the same orbital trauma patterns and were also managed with PSI. However, the control group patients were treated using 'slice-by-slice' virtual orbital reconstruction. Mean volume differences between the intact and reconstructed orbit were 0.65 ± 0.26 cm3 in the main group (n = 23) and 0.57 ± 0.23 cm3 in the control (n = 27; p = 0.837). In both groups, no cases of implant malposition or enophthalmos were detected after surgery. Orbital shape difference was similar for the main group and the control, at -3.3 ± 3.5% and 3.25 ± 2.5%, respectively (p = 0.929). Diplopia was diagnosed at the 3-month follow-up in 13.0% of the main group and in 11.1% of the control (p = 0.651). The average times spent on computer-aided design (CAD) procedures, including segmentation, virtual orbital reconstruction, and PSI design, were 36.7 ± 6.9 min in the main group and 72.9 ± 7.7 min in the control group (p < 0.001). Within the limitations of the study it seems that PSI based on automated virtual reconstruction is a relevant alternative treatment option for orbital fractures because of its clinical efficacy that is similar to PSI based on a 'slice-by-slice' CAD protocol.

TOTAL MANDIBULAR DEFECT RECONSTRUCTION BY TOTAL TITANIUM PATIENT-SPECIFIC IMPLANT: CLINICAL EFFICACY AND LONG TERM FOLLOW UP. CLINICAL CASE.

The aim of this clinical case in demonstrating the possibility of replacing total defect of the mandible with a patient specific implant and the result of long-term follow up. Literature data on the replacement of total mandibular defects are extremely limited and they are presented by only several clinical cases where various surgical approaches were used. In the available literature, there are two approaches to solving this problem, including the replacement of the jaw with vascularised bone grafts, of which the fibula flap is the most promising, and the implantation of endoprostheses of the jaws, of which patient-specific anatomical endoprostheses made using additive technologies are the most advanced. The concept of using patient-specific endoprostheses of the whole mandible is considered revolutionary because it has a number of significant benefits, including the greatest accuracy in restoring the anatomical shape of the mandible. One of the unresolved problems associated with the installation of total mandibular endoprostheses is the prosthetic rehabilitation of patients using fixed structures. The analysis of the presented case can be a good tool for the clinician and bioengineer while making the final decision on the treatment method and modality in patients who need an identical option for the repair of a mandibular defect. Based on CT data, we can conclude that the employed approach, methodology of design and manufacture of patient-specific titanium mandibular endoprosthesis for the total defect demonstrated the sufficient efficacy, which suggest the need for further systematic studies to address this issue.

Automatic evaluation of the orbital shape after application of conventional and patient-specific implants: Correlation of initial trauma patterns and outcome.

PURPOSE: To evaluate the precision of orbital shape reconstructions using either conventional plates (CPs) or patient-specific implants (PSIs) to treat different types of orbital fractures, and to evaluate their clinical outcomes. METHODS: A total of 92 orbital-reconstruction patients were included. Forty-seven patients, treated with PSIs, formed the main group. The remainder, treated with CPs, were the control group. All patients were examined pre- and postoperatively using computerized tomography (CT) and evaluated for enophthalmos and diplopia. Evaluation of differences in orbital shape between damaged and intact orbits after surgery was performed by commercial orbital analysis software. RESULTS: In the main group, mean orbital shape difference between damaged and intact orbits after surgery was 0.137 ± 0.8 cm3 (range -1.7-2.3 cm3). In the control group, the mean shape difference was 1.05 ± 1.9 cm3 (range -1.8-8.3 cm3), significantly higher (p = 0.007). Diplopia occurred in seven PSI patients three months after surgery (14.9%) and in thirteen CP patients (28.9%) (p = 0.181). Enophthalmos occurred in five PSI patients (10.6%) and in sixteen CP patients (35.6%) (p = 0.001). CONCLUSION: Precise orbital reconstruction prevents the development of enophthalmos after trauma in patients with orbital wall fractures. In patients with preserved infraorbital buttresses and posterior orbital ledges, there were no significant clinical differences between PSIs and CPs. For cases requiring cantilevered reconstruction, including those with zigomatic or maxillary fragment repositioning, preference should be given to the PSI procedure for both effectiveness and predictability.

Reliability of orbital volume measurements based on computed tomography segmentation: Validation of different algorithms in orbital trauma patients.

PURPOSE: To compare the most common methods of segmentation for evaluation of the bony orbit in orbital trauma patients. MATERIALS AND METHODS: Computed tomography scans (before and after treatment) from 15 patients with unilateral blowout fractures and who underwent orbital reconstructions were randomly selected for this study. Orbital volume measurements, volume difference measurements, prolapsed soft tissue volumes, and bony defect areas were made using manual, semi-automated, and automated segmentation methods. RESULTS: Volume difference values between intact and damaged orbits after surgery using the manual mode were 0.5 ± 0.3 cm3, 0.5 ± 0.4 cm3 applying semi-automated method, and 0.76 ± 0.5 cm3, determined by automated segmentation (р = 0.216); the mean volumes (MVs) for prolapsed tissues were 3.0 ± 1.9 cm3, 3.0 ± 2.3 cm3, and 2.8 ± 3.9 cm3 (p = 0.152); and orbital wall defect areas were 4.7 ± 2.8 cm2, 4.75 ± 3.1 cm2, and 4.9 ± 3.3 cm2 (p = 0.674), respectively. CONCLUSIONS: The analyzed segmentation methods had the same accuracy in evaluation of volume differences between two orbits of the same patient, defect areas, and prolapsed soft tissue volumes but not in absolute values of the orbital volume due to the existing diversity in determination of anterior closing. The automated method is recommended for common clinical cases, as it is less time-consuming with high precision and reproducibility.

Analysis of regular dental checkups of kyivites in stomatological establishments of various property forms.

OBJECTIVE: The aim: carry out analysis of regular dental checkups in Kyiv in state and private dental establishments. PATIENTS AND METHODS: Materials and methods: The analysis was conducted using the statistical reports (approved standard №20) which have been obtained in Kyiv and Ukraine from 2008 till 2017. The method of copying data with using statistical estimation methods was applied. RESULTS: Results: The authors have established significant dental preventive measures decline in Kyiv state dental establishments from 2008 till 2017. A tendency toward increased private dental sector within the dental prevention has been noted. CONCLUSION: Conclusions: The obtained results will be used to substantiate concepts of municipal stomatological dental care improvement as well as to introduce the university clinic model.