OBJECTIVE: To investigate the influence of material and printing orientation on wear resistance and flexural properties of one low force SLA- and two DLP-printed splint materials and to compare these 3D-printed splints to a subtractively manufactured splint material.
METHODS: Two DLP-printed (V-Print splint, LuxaPrint Ortho Plus) and one low force SLA-printed (Dental LT Clear) material, where specimens were printed in three printing orientations (0°, 45°, 90°), were investigated. In addition, one milled splint material (Zirlux Splint Transparent) was examined. A total of 160 specimens were produced for both test series. The two-body wear test was performed in a chewing simulator (80\'000 cycles at 50 N with 5-55 °C thermocycling). Steatite balls were used as antagonists. The wear pattern was analyzed with a 3D digital microscope in terms of maximum vertical intrusion depth (mm) and total volume loss (mm³). The flexural properties were investigated by three-point bending in accordance with ISO 20795-1: 2013 (denture base polymers). The flexural strength (MPa) and the flexural modulus (MPa) were measured. Two-way ANOVA was performed to investigate the effects of the two independent variables material and printing orientation for the three 3D-printed materials. The comparison of the printing orientations within one material was carried out with one-way ANOVA with post-hoc Tukey tests.
RESULTS: Two-way ANOVA revealed that wear and flexural properties are highly dependent on the 3D-printed material (p < 0.001). Across groups, a significant effect was observed for wear depth (p = 0.031) and wear volume (p = 0.044) with regard to printing orientation but this was not found for flexural strength (p = 0.080) and flexural modulus (p = 0.136). One-way ANOVA showed that both DLP-printed groups showed no significant differences within the printing orientations in terms of wear and flexural properties. Dental LT Clear showed that 90° oriented specimens had higher flexural strength than 0° oriented ones (p < 0.001) and 45° oriented specimens also showed higher values than 0° ones (p = 0.038). No significant differences were observed within the printing orientations for flexural modulus and wear behaviour within this group. T-tests showed that the milled splints exhibited statistically higher wear resistance and flexural properties compared to all three 3D-printed splint materials (p < 0.001) and that highly significant differences were found between the 3D-printed splint materials for both test series.
CONCLUSIONS: Within the limitations of this in vitro study, it can be stated that wear behaviour and flexural properties are highly dependent on the 3D-printed material itself. Currently, milled splints exhibit higher wear resistance and flexural properties compared to 3D-printed splint materials. The printing orientation has a minor influence on the properties investigated. Nevertheless, two-way ANOVA also showed a significant influence of printing orientation in the wear test across groups and one-way ANOVA detected significant effects for SLA material in terms of flexural strength, with printing in 90° showing the highest flexural strength. Therefore, anisotropy was found in SLA material, but it can be limited with the employed printing parameters. Both DLP-printed materials showed no significant difference within the printing orientation.

To investigate the impact of a Ti-Sr-O technology, applied to either a turned surface or an SLA surface, on the mechanical robustness of osseointegration, benchmarked against the SLActive surface.
Ti discs (6.25-mm-diameter and 2-mm-thick) with three different surfaces were inserted on the proximal-anterior part of the tibial plateau of adult Swedish loop rabbits: (I) turned surface modified with Ti-Sr-O (turned + Ti-Sr-O), (II) SLA surface modified with Ti-Sr-O (SLA + Ti-Sr-O), and (III) SLActive surface (SLActive). Following a healing period of 2 weeks and 4 weeks, the pull-out (PO) force needed to detach the discs from the bone was assessed, as a surrogate of osseointegration.
The SLActive surface exhibited statistically significant higher median PO forces, compared with the SLA + Ti-Sr-O surfaces at both 2- and 4 weeks post-op (p > .05). In this study, no single turned + Ti-Sr-O surface disk was integrated.
The tested Ti-Sr-O technology failed to enhance osseointegration; however, this finding may be related to the inappropriateness of the rabbit tibia plateau model for assessing third-generation implant surface technologies, due to the limited diffusion and clearance at the disk-bone interface.

OBJECTIVE: Laser interstitial thermal therapy (LITT) is increasingly being used in the treatment of brain tumors, whereas high-quality evidence of its effectiveness is lacking. This pilot examined the feasibility of conducting a randomized controlled trial (RCT) in patients with irresectable newly diagnosed glioblastoma (nGBM), and generated data on technical feasibility and safety.
METHODS: We included patients with irresectable nGBM with KPS ≥ 70 and feasible trajectories to ablate ≥ 70% of the tumor volume. Patients were initially randomized to receive either biopsy combined with LITT or biopsy alone, followed by chemoradiation (CRT). Randomization was stopped after 9 patients as the feasibility endpoint with respect to willingness to be randomized was met. Main endpoints were feasibility of performing an RCT, technical feasibility of LITT and safety. Follow-up was 3 months.
RESULTS: A total of 15 patients were included, of which 10 patients received a biopsy followed by LITT and 5 patients a biopsy. Most patients were able to complete the follow-up procedures (93% clinical, 86% questionnaires, 78% MRI). Patients were planned within 3 weeks after consultation (median 12 days, range 8-16) and no delay was observed in referring patients for CRT (median 37 days, range 28-61). Two CD ≥ 3 complications occurred in the LITT arm and none in the biopsy arm.
CONCLUSIONS: An RCT to study the effectiveness of LITT in patients with an irresectable nGBM seems feasible with acceptable initial safety data. The findings from this pilot study helped to further refine the design of a larger full-scale multicenter RCT in the Netherlands. Protocol and study identifier: The current study is registered at clinicaltrials.gov (EMITT pilot study, NTR: NCT04596930).

UNASSIGNED: This study aims to evaluate the efficacy and safety of two types of sandblasted with large-grit and acid-etched (SLA) surface implants with different surface roughness. Patients and.
UNASSIGNED: This study was conducted based on a clinical record review of 55 patients (mean age, 53.00 years). A total of 80 SLA surface implants was placed. Among the 80 implants, 38 implants placed in 29 subjects had surface roughness (Ra) of 3.09 μm (test group, TG), while the other 42 implants placed in 31 subjects had a surface roughness (Ra) of 2.50 μm (control group, CG). A comparison was made of implant primary/ secondary stability; success and survival rates; marginal bone loss; and soft tissue assessment including probing pocket depth (PPD), plaque index (PI), gingival index (GI), and bleeding on probing (BOP) between the groups at 1 year after implant placement.
UNASSIGNED: Among the implants that were initially registered, 1 from the TG and 4 from the CG dropped out, leaving 37 implants in the TG and 38 implants in the CG to be traced and analyzed. Although 1 TG case showed unstable primary stability, all cases showed stable secondary stability. Success and survival rates at 1 year after implant placement were 100% in both groups. Marginal bone loss was 0.07 mm and 0.00 mm for the TG and CG, respectively, but the difference was not significant. Among the several parameters for evaluation of soft tissue, the TG showed lower PI at 1 year after implant placement (TG=0.00, CG=0.29; P=0.0004), while the remaining categories showed no significant difference between the groups.
UNASSIGNED: This study shows that the two types of SLA implants with different surface roughness have no difference in efficacy or safety. Therefore, both of the implants can be used safely and with promising outcomes.

Recent burgeoning development in material science has introduced a 3D-printable, nanohybrid composite resin restorative material. However, its performance has not yet been investigated. This study evaluates the stain susceptibility and efficacy of different stain removal techniques. A total of 120 labial veneers were fabricated using milling (n = 60) and SLA 3D-printing (n = 60). Based on the immersion media: coffee, tea and artificial saliva, each group was divided into three sub-groups (n = 20). Stain susceptibility was evaluated by calculating color difference (∆E00) at 12 and 24 days using a spectrophotometer against black and white backgrounds. Collected data were analyzed with ANOVA and Tukey\'s post hoc test (p < 0.05). A significant interaction effect was found between the staining mediums and fabrication methods in both black and white backgrounds (p < 0.001). 3D-printed restorations showed significantly higher stain susceptibility than milled restorations (p < 0.001). Prolonged immersion time increased the color difference in both groups. In-office bleaching was more effective in stain removal in both 3D-printed and milled restoration groups. The susceptibility of the presented novel 3D-printed restorative material to color changes in different immersion mediums was clinically not-acceptable. The clinicians might expect the need to replace the restoration after 1-2 years and thus, recommendation for the use of such a material as a permanent restoration cannot be made but rather as a long-term temporary restoration.

Different approaches for digital workflows have already been presented for their use in palatal plates for newborns and infants. However, there is no evidence on the accuracy of CAD/CAM manufactured orthodontic appliances for this kind of application. This study evaluates trueness and precision provided by different CAM technologies and materials for these appliances. Samples of a standard palatal stimulation plate were manufactured using stereolithography (SLA), direct light processing (DLP) and subtractive manufacturing (SM). The effect of material (for SM) and layer thickness (for DLP) were also investigated. Specimens were digitized with a laboratory scanner (D2000, 3Shape) and analyzed with a 3D inspection software (Geomagic Control X, 3D systems). For quantitative analysis, differences between 3D datasets were measured using root mean square (RMS) error values for trueness and precision. For qualitative analysis, color maps were generated to detect locations of deviations within each sample. SM showed higher trueness and precision than AM technologies. Reducing layer thickness in DLP did not significantly increase accuracy, but prolonged manufacturing time. All materials and technologies met the clinically acceptable range and are appropriate for their use. DLP with 100 µm layer thickness showed the highest efficiency, obtaining high trueness and precision within the lowest manufacturing time.

The treatment of peri-implantitis implies the decontamination of the surface of the fixture. This study aims to analyze the effect of the erbium-doped yttrium aluminum garnet laser (Er: YAG) on sandblasted and acid-etched (SLA) titanium. 30 titanium SLA disks were divided into three groups. In Group 1, the disks were left intact; on the contrary, both Groups 2 and 3 were irradiated with the Er: YAG laser at different settings, with a pulse duration of 300 μs and a period of 30 s. Group 2 was irradiated at 1 W and 100 mJ/pulse and Group 3 at 4 W and 400 mJ/pulse. The superficial changes at chemical, nano, and microscopical levels were detected through the use of Fourier-transform infrared spectroscopy, atomic force microscopy, and scanning electron microscope. The Kruskal-Wallis test, followed by the Dunn-Bonferroni Post Hoc analysis, detected the presence of statistically significant differences among the groups. The level of significance was p ≤ 0.05. Results showed that Er: YAG irradiation promoted a significant (p < 0.05) increase of oxides and a decrease of microscopical roughness and porosity on SLA disks. However, the protocol tested on group 3 seemed to be too aggressive for the titanium surface, as shown by the presence of micro-cracks and signs of coagulation, melting, and microfractures. In conclusion, Group 2 showed significantly minor surface alterations with respect to Group 3, and the increase of superficial oxide level, the decrease of porosity, and micro-roughness represent a positive alteration that could protect the materials against bacterial adhesion.

This study aimed to assess the safety and efficacy of MR-guided stereotactic laser ablation (SLA) therapy in the treatment of pediatric brain tumors.
Data from 17 North American centers were retrospectively reviewed. Clinical, technical, and radiographic data for pediatric patients treated with SLA for a diagnosis of brain tumor from 2008 to 2016 were collected and analyzed.
A total of 86 patients (mean age 12.2 ± 4.5 years) with 76 low-grade (I or II) and 10 high-grade (III or IV) tumors were included. Tumor location included lobar (38.4%), deep (45.3%), and cerebellar (16.3%) compartments. The mean follow-up time was 24 months (median 18 months, range 3-72 months). At the last follow-up, the volume of SLA-treated tumors had decreased in 80.6% of patients with follow-up data. Patients with high-grade tumors were more likely to have an unchanged or larger tumor size after SLA treatment than those with low-grade tumors (OR 7.49, p = 0.0364). Subsequent surgery and adjuvant treatment were not required after SLA treatment in 90.4% and 86.7% of patients, respectively. Patients with high-grade tumors were more likely to receive subsequent surgery (OR 2.25, p = 0.4957) and adjuvant treatment (OR 3.77, p = 0.1711) after SLA therapy, without reaching significance. A total of 29 acute complications in 23 patients were reported and included malpositioned catheters (n = 3), intracranial hemorrhages (n = 2), transient neurological deficits (n = 11), permanent neurological deficits (n = 5), symptomatic perilesional edema (n = 2), hydrocephalus (n = 4), and death (n = 2). On long-term follow-up, 3 patients were reported to have worsened neuropsychological test results. Pre-SLA tumor volume, tumor location, number of laser trajectories, and number of lesions created did not result in a significantly increased risk of complications; however, the odds of complications increased by 14% (OR 1.14, p = 0.0159) with every 1-cm3 increase in the volume of the lesion created.
SLA is an effective, minimally invasive treatment option for pediatric brain tumors, although it is not without risks. Limiting the volume of the generated thermal lesion may help decrease the incidence of complications.

Three-dimensional (3D) printed titanium and its alloys have broad application prospect in the field of biomedical implant materials, although the biological performance of the original surface should be improved. Learning from the development experience of conventional titanium implants, to construct a hierarchical hybrid topological surface is the future direction of efforts. Since the original 3D-printed (3D hereafter) Ti6Al4V surface inherently has micron-scale features, in the present study, we introduced submicron-scale pits on the original surface by acid etching to obtain a hierarchical micro/submicro-textured surface. The characteristic and biological performance of the 3D-printed and acid-etched (3DA hereafter) surface were evaluated in vitro and in vivo, compared with the conventional sandblasted, large-grit, acid-etched (SLA hereafter) surface. Our results suggested the adhesion, proliferation and osteogenic differentiation of bone marrow derived mesenchymal stromal cells (BMSCs), as well as the in vivo osseointegration on 3DA surfaces were significantly improved. However, the overall osteogenic performance of the 3DA surface was not as good as the conventional SLA surface.

Stomata formed at high relative air humidity (RH) close less as leaf dries; an effect that varies depending on the genotype. We here quantified the contribution of each stomatal response characteristic to the higher water loss of high RH-grown plants, and assessed the relationship between response characteristics and intraspecific variation in stomatal size. Stomatal size (length multiplied by width), density and responsiveness to desiccation, as well as pore dimensions were analyzed in ten rose cultivars grown at moderate (60%) or high (85%) RH. Leaf morphological components and transpiration at growth conditions were also assessed. High growth RH resulted in thinner (11%) leaves with larger area. A strong positive genetic correlation of daytime and nighttime transpiration at either RH was observed. Stomatal size determined pore area (r=0.7) and varied by a factor of two, as a result of proportional changes in length and width. Size and density of stomata were not related. Following desiccation, high RH resulted in a significantly lower (6-19%) decline of transpiration in three cultivars, whereas the relative water content (RWC) of high RH-expanded leaflets was lower (29-297%) in seven cultivars. The lower RWC of these leaflets was caused by (a) higher (33-72%) stable transpiration and/or (b) lower (12-143%) RWC at which this stable transpiration occurred, depending on the cultivar. Stomatal size was significantly correlated with both characteristics (r=0.5 and -0.7, respectively). These results indicate that stomatal size explains much of the intraspecific variation in the regulation of transpiration upon water deprivation on rose.