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Introduction Many low resourced low- and middle-income countries (LMICs) do not have access to (high tech) developments in the medical field. The aim of this study is to research how a contemporary high-tech solution, such as customized medical implants, can be transferred to low resource LMICs. Materials and methods We explored the internet to retrieve data regarding internet coverage, services providing free email accounts, and the availability of connecting devices. Additionally, a computerized search was performed for currently available PSI concepts and other important emerging technologies with potential value in craniomaxillofacial surgery. Lastly, we searched the internet for the availability of CT scan devices and smartphones in the LMICs. Results Internet penetration and access to computers/smartphones is low in the LMICs. Moreover, availability of radiology departments and radiologists is very limited (60 radiologists per 190 million Nigerian inhabitants) and a lack of knowledge concerning import regulations and customs clearance, limits the accessibility/availability for patient-specific implants, since this is crucial in developing and delivering these devices. Lastly, appropriate training and instrumentation are vital (yet, currently difficult) to acquire and foresee, in order to achieve the best post-operative results. Conclusion This research confirms great difficulties achieving our aims but with persistence and adoption of well-constructed programs it should be possible.

Purpose. The objective of this study was to analyse the possibilities of using 4D CT scanning for the tracking of patients’ mandibles. Methods. A clinical 256-slice Revolution CT was used in obtaining 4D CT scans without table movement, with a novel mandibular phantom, mounted on a programmable six degrees-of-freedom Stewart Platform in motion. The phantom was used to simulate mandibular motions which are combinations of rotations with translations (depression, elevation, protrusion, retrusion and laterotrusion). The phantom was scanned five times during identical motion patterns with a dynamic CT acquisition protocol. An image processing workflow consisting of a pairwise rigid registration and semi-automatic segmentation was developed to extract kinematic parameters (cardan angles and point-of-interest displacements) from the dynamic sequences. Reproducibility was investigated by the 95% confidence interval and the absorbed organ dose to organs of interest in the primary beam were also estimated and compared to those of a standard CT scan of the brain Results. The maximum average 95% confidence interval for the displacement across all time points for the five repetitions was 0.61 mm (Y axis). In terms of rotations, the maximum average 95% confidence interval across all time points for the five repetitions was 1.39° (X axis). The effective dose for the dynamic scan was found to be 1.3 mSv, for a CTDIvol of 63.95 mGy and a DLP of 1023.14 mGycm. The absorbed organ doses were similar to organ doses during a clinical head CT scan. Conclusions. A framework is proposed to use 4D CT scanning as a possible methodology to evaluate the motion of the temporomandibular joint. The scanning protocol allows to visualise the motion by applying a semi-automated segmentation and registration. A graphical representation of all displacements in the three spatial dimensions can depict multiple points-of-interest at once during the same acquisition. A novel type of phantom was also introduced which simulates mandibular movement with six degrees-of-freedom (three translations and three rotations).

Introduction Maximizing osteointegration potential of three-dimensionally-printed porous titanium (3DPPT) is an ongoing focus in biomaterial research. Many strategies are proposed and tested but there is no weighted comparison of results. Methods We systematically searched Pubmed and Embase to obtain two pools of 3DPPT studies that performed mechanical implant-removal testing in animal models and whose characteristics were sufficiently similar to compare the outcomes in meta-analyses (MAs). We expanded these MAs to multivariable meta-regressions (moderator analysis) to verify whether statistical models including reported scaffold features (e.g., “pore-size”, “porosity”, “type of unit cell”) or post-printing treatments (e.g., surface treatments, adding agents) could explain the observed differences in treatment effects (expressed as shear strength of bone-titanium interface). Results “Animal type” (species of animal in which the 3DPPT was implanted) and “type of post-treatment” (treatment performed after 3D printing) were moderators providing statistically significant models for differences in mechanical removal strength. An interaction model with covariables “pore-size” and “porosity” in a rabbit subgroup analysis (the most reported animal model) was also significant. Impact of other moderators (including “time” and “location of implant”) was not statistically significant. Discussion/conclusion Our findings suggest a stronger effect from porosity in a rat than in a sheep model. Additionally, adding a calcium-containing layer does not improve removal strength but the other post-treatments do. Our results provide overview and new insights, but little narrowing of existing value ranges. Consequent reporting of 3DPPT characteristics, standardized comparison, and expression of porosity in terms of surface roughness could help tackle these existing dilemmas. Graphical abstract

The aim of this study was to retrospectively assess the osteosynthesis material–related morbidity rates of third-generation (3.0) slotplates, and to compare those with the previously researched second-generation (2.0) slotplates. In the 2.0 slotplate design, there were additional tabs in line with the vertical slotted screw hole; in between these tabs, the additional locking screw was placed. In the 3.0 slotplates, these tabs were replaced by a full screw hole for the locking screw, and the 3.0 slotplates are slightly broader than the 2.0 slotplates. Osteosynthesis material−related morbidity rates after Le Fort I−type, zygoma-valgisation, and chin osteotomies were assessed in a cohort receiving 3.0 slotplates in a tertiary care centre and compared to a previously analysed cohort receiving 2.0 slotplates in the same tertiary care centre. Medical records of 77 patients (101 surgeries) receiving 3.0 slotplates were reviewed. Plate infection and plate removal rates were low in the 3.0 slotplate group (2.6% (p = 0.123) and 3.9% (p = 0.103), respectively). No delayed union or non-union occurred in the 3.0 slotplate group. Comparing the morbidity rates with the 2.0 slotplate cohort did not yield any significant differences. Although there was a tendency towards better outcomes with 3.0 slotplates compared to the 2.0 slotplates, the outcome differences did not reach statistical significance.

Background Various studies have investigated the load-bearing capacity of patient-specific cranial implants. However, little attention has been given to the evaluation of the design of ceramic-titanium (CeTi) implants. Methods A biomechanical evaluation of 3 patient-specific cranial implants was performed using finite element analysis. Results The results of the analyses allowed the identification of the implant regions as well as the magnitudes of the maximum stresses on, and displacements along, these regions after traumatic impact. The analyses also showed that polyether ether ketone cranial implants offer inferior brain and neurocranial protection due to their high flexibility and local peak stresses at the bone-screw interface. In contrast, CeTi implants were able to evenly distribute the stresses along the interface and thus reduced the risk of neurocranial fracture. The scaffold structure at the border of these implants reduced stress shielding and enhanced bone ingrowth. Moreover, brain injuries were less likely to occur, as the CeTi implant exhibits limited deflection. Conclusions From the finite element analyses, CeTi cranial implants appear less likely to induce calvarial fractures with a better potential to protect the brain under impact loads.

Study Design: Technical note. Objective: Computer-aided design and computer-aided manufacturing (CADCAM) is commonly used in craniomaxillofacial (CMF) surgery because of its advantage in customizing medical devices. We used this technology to create individualized, resin-bonded 3-dimensionally printed titanium arch bars. Method: This article describes a patient specific, three-dimensionally (3D) printed, resin-bonded arch bar as an alternative to the classical intermaxillary fixation systems. Results: The ease of application and removal, as well as the protection of the periodontal and cheek tissues, and operator fingers, made this a comfortable technique for both the patient and practitioner. Conclusions: A patient-specific 3D-printed titanium arch bar can be useful in the arsenal of the maxillofacial surgeon.