Influence of fabrication method on the marginal fit of temporary restorations.

Computer-aided manufacturing (CAM) technology allows the use of different manufacturing techniques. This in vitro study aimed to evaluate the marginal fit of temporary restorations manufactured using conventional chairside methods, milling, and three-dimensional printing. Fifteen 3-element temporary restorations specimens were produced and categorized into three groups: non-digital, obtained using the conventional chairside method (GC); milled (GM); and three-dimensionally printed (GP). Marginal fit was assessed using scanning electron microscopy (SEM) performed under two conditions: one with only the central screw tightened, and the other with all three screws tightened. Horizontal misfit values were categorized as over-, equal-, and under-extended and qualitatively analyzed. Statistical analysis was performed using the Tukey-Kramer test (α=0.05). In the vertical assessment, three-dimensionally printed restorations demonstrated greater misfit than restorations obtained by milling and the conventional chairside method (P<0.05). In the horizontal assessment, the misfit in the GP group was significantly higher than that in the GM and GC groups. Restorations obtained using the conventional chairside method and milled provisional restorations showed more favorable results than three-dimensionally printed restorations.

Periodontitis and non-communicable diseases in a Brazilian population, a cross-sectional study, Vila Velha-ES, Brazil.

BACKGROUND: The objective of this study was to examine the hypothesis that periodontal disease is associated with chronic non-communicable diseases. METHODS: In this cross-sectional study, we evaluated the periodontal health condition of the population, based on the community periodontal index, as well as the number of missing teeth and the presence of systemic health conditions. We quantified the association between oral health and the presence of chronic diseases using simple logistic regression, adjusting for confounding factors including age, smoking, and overweight. RESULTS: The study population consisted of 334 volunteers, aged between 19 and 81 years. In patients over 45 years old, periodontal disease was found to be significantly associated with hypertension and diabetes. Furthermore, in female patients, periodontal disease was significantly associated with hypertension, diabetes, and cancer. CONCLUSION: Our findings indicate that periodontal disease is positively and significantly associated with both arterial hypertension and diabetes, independent of potential confounding factors.

The Scalloped Surgical Guide as an Alternative to Flat Bone Reduction Guide in Full-Arch Implant Restoration.

The goal of this clinical report was to present an alternative to traditional flat bone reduction guides, using a custom-designed 3-dimensional (3D)-printed guide according to the future gingival margin of the planned dentition. A 61-year-old woman with concerns regarding her smile appearance was presented. The initial examination revealed excessive gingival show accompanied by excessive overjet. The dentition was in a failing situation. The proposed treatment plan, relying on the sufficient amount of bone and keratinized tissue, consisted of recontouring of the alveolar ridge and gingiva and placement of 6 implants and an FP-1 prosthesis after extraction of all remaining maxillary teeth. Digital smile design was completed, and a fully digitally guided surgery was planned. This consisted of using 3 surgical guides, starting with the fixation pin guide, continuing with the scalloped hard- and soft-tissue reduction guide, and finally the implant placement template. Following the surgery, the patient received a temporary restoration, and on the 4-month follow-up, a new polymethyl meta-acrylate temporary prosthesis was delivered. The patient's 7-month follow-up is presented in the article. The report of this triple-template guided surgery indicated that digital 3D planning is a considerably predictable tool to properly establish and evaluate future occlusal plane, smile line, and lip support. Scalloped guides seem to be an excellent alternative to conventional bone reduction guides since they require less bone removal and improve patient comfort during surgery.

Influence of fabrication method on the marginal fit of temporary restorations

Abstract Computer-aided manufacturing (CAM) technology allows the use of different manufacturing techniques. This in vitro study aimed to evaluate the marginal fit of temporary restorations manufactured using conventional chairside methods, milling, and three-dimensional printing. Fifteen 3-element temporary restorations specimens were produced and categorized into three groups: non-digital, obtained using the conventional chairside method (GC); milled (GM); and three-dimensionally printed (GP). Marginal fit was assessed using scanning electron microscopy (SEM) performed under two conditions: one with only the central screw tightened, and the other with all three screws tightened. Horizontal misfit values were categorized as over-, equal-, and under-extended and qualitatively analyzed. Statistical analysis was performed using the Tukey-Kramer test (α=0.05). In the vertical assessment, three-dimensionally printed restorations demonstrated greater misfit than restorations obtained by milling and the conventional chairside method (P<0.05). In the horizontal assessment, the misfit in the GP group was significantly higher than that in the GM and GC groups. Restorations obtained using the conventional chairside method and milled provisional restorations showed more favorable results than three-dimensionally printed restorations.

Influence of scanbody design and intraoral scanner on the trueness of complete arch implant digital impressions: An in vitro study.

This study aimed to compare the accuracy of full-arch digital implant impressions using seven different scanbodies and four intraoral scanners. A 3D-printed maxillary model with six implants and their respective multi-unit abutments was used for this study. Seven scanbodies (SB1, SB2, SB3, SB4, SB5, SB6, and SB7) and four intraoral scanners (Primescan®, Omnican®, Trios 3®, and Trios 4®) were assessed. Each combination group was scanned ten times and a dental lab scanner (D2000, 3Shape) was used as a reference. All scans were exported as STL files, imported into Convince software (3Shape) for alignment, and later into Blender software, where their 3D positions were analyzed using a Python script. The 3D deviation, angular deviation, and linear distance between implants #3 and #14 were also measured. Accuracy was measured in terms of "trueness" (scanbody 3D deviation between intraoral scan and desktop scan). Kruskal-Wallis followed by the Bonferroni correction was used to analyze the data (⍺ = .05). The study found statistically significant differences in digital impression accuracy among the scanners and scanbodies (p<0.001). When comparing different intraoral scanners, the Primescan system showed the smallest 3D deviation (median 110.59 µm) and differed statistically from the others, while Trios 4 (median 122.35 µm) and Trios 3 (median 130.62 µm) did not differ from each other (p = .284). No differences were found in the linear distance between implants #3 and #14 between Trios 4, Primescan, and Trios 3 systems. When comparing different scanbodies, the lowest median values for 3D deviation were obtained by SB2 (72.27µm) and SB7 (93.31µm), and they did not differ from each other (p = .116). The implant scanbody and intraoral scanner influenced the accuracy of digital impressions on completely edentulous arches.

Digitally Guided Lateral Sinus Floor Elevation With Simultaneous Implant Placement: 3 Case Reports With Technical Considerations.

A sinus floor elevation via lateral window (LSFE) is one of the most widely used bone augmentation procedures for implant therapy in the posterior area of the maxilla. Locating and preparing a correct opening window on the lateral sinus wall is a key step of this procedure. Conventionally, the surgeon designs and locates the window after the flap is reflected based on the information obtained from cone-beam computed tomography (CBCT) images or other diagnostic aids. Nevertheless, in spite of the advancements in CBCT imaging, clinicians may still experience hardships in situating and procuring meticulous access to the maxillary sinus by using CBCT alone. Therefore, in cases requiring an LSFE simultaneous to implant placement, a maxillary sinus surgical guide has been tested and reported to be the amiable method to be utilized as a conjunct to prevent unpredictable consequences according to its application in implying both the direction for the implant and the location of the lateral window. This article presents 3 clinical cases with a fully digital approach to guide the opening of the lateral wall of the maxillary sinus as well as the simultaneous placement of a single implant in an ideal 3D position. Based on the CBCT images and intraoral scan, a surgical guide was fabricated based on 3D software. During surgery, this teeth-supported template can be placed intraorally, guiding sinus window opening preparation. This technique makes the sinus window opening procedure simple and predictable, reduces surgical time and the risk of complications, and allows the placement of the implant in the ideal 3D position.

Cost and effectiveness of 3-dimensionally printed model using three different printing layer parameters and two resins.

STATEMENT OF PROBLEM: When 3-dimensional printing casts, the operator can change the type of resin and the printing layer thickness, reducing the fabrication time. However, how these parameters affect the accuracy of 3-dimensionally printed casts is unknown. PURPOSE: The purpose of this in vitro study was to evaluate the accuracy of 3-dimensionally printed casts by using a stereolithography (SLA) 3-dimensional printer (Forms2) with 3 different layer thickness (25, 50, and 100 µm) and 2 different resins (Gray and Cast) and by comparing the time to obtain each cast. MATERIAL AND METHODS: One master cast was scanned, and a single file was printed several times. The printed casts were then scanned by using a laboratory scanner. The standard tessellation language (STL) files provided by the laboratory scanner were superimposed and compared by using a software program (Geomagic Control; 3D Systems). The 2-way ANOVA test was used for the trueness evaluation, followed by the Tukey test to identify differences among the groups (α=.05). RESULTS: No statistically significant differences in accuracy were found among the 3 different layers for either resin (P>.05). Printing time doubled as layer thickness decreased. CONCLUSIONS: This study showed that when printing casts, the fastest printing settings can be used without losing accuracy and that the laboratory digital workflow can be accelerated with selection of the resin and cast layer, as the type of resin and layer thickness did not influence the quality of the casts.

Assessment of Deviations of Implants Installed with Prototyped Surgical Guide and Conventional Guide: In Vitro Study.

OBJECTIVE: The study aimed to assess the angular and linear deviations of implants installed in mannequins aided by surgical guides produced with the techniques of dual tomography (DT), model-based tomography (MT), and nonprototyped guide. MATERIALS AND METHODS: Implants were installed in mannequins of a partially edentulous maxilla and divided into three groups: Group C (n = 20), implants installed using the conventional technique with flap opening and conventional guide; Group DT (n = 20), implants installed using guided surgery with the dual tomography technique; and Group MT (n = 20), implants installed using the model-based tomography technique. After implant installation, the mannequin was subjected to a computed tomography (CT) to measure the linear and angular deviations of implant positioning relative to the initial planning on both sides. RESULTS: There was a higher mean angular deviation in group C (4.61 ± 1.21, p ≤ 0.001) than in groups DT (2.13 ± 0.62) and MT (1.87 ± 0.94), which were statistically similar between each other. Similarly, the linear deviations showed group C with the greatest discrepancy in relation to the other groups in the crown (2.17 ± 0.82, p = 0.007), central (2.2 ± 0.77, p = 0.004), and apical (2.34 ± 0.8, p = 0.001) regions. CONCLUSION: The techniques of DT and MT presented smaller angular and linear deviations than the conventional technique with the nonprototyped guide. There was no difference between the two-guided surgery techniques.

Accuracy of partially and fully guided surgical techniques for immediate implant placement: An in vitro assessment.

STATEMENT OF PROBLEM: Optimal implant positioning is essential to achieving predictable results. Computer-guided surgery has been reported to be an accurate technique for implant placement in healed sites, but the accuracy of guided techniques for immediate implant placement into fresh sockets is still unclear. PURPOSE: The purpose of this experimental randomized split-mouth study in pig jaws was to determine the accuracy of partially and fully guided surgical techniques for immediate implant placement into fresh sockets and to compare 2 different methods of implant position deviations analysis. MATERIAL AND METHODS: Twenty implants were installed in 10 pig jaws using 2 different techniques: partially guided (n=10) and fully guided (n=10). Cone beam computed tomography and digital scanning were performed before and after the surgical procedure to plan the virtual implant position and fabricate the surgical guide, as well as to determine implant position deviations. Two methods were used to evaluate implant deviations: tomographic and digital scanning. The Shapiro-Wilk test of normality was used. Deviation comparisons were carried out by using paired t tests (α=.05), and intraclass correlation coefficient (ICC) was computed to assess the agreement between the 2 methods of implant deviation analysis. RESULTS: In the tomographic analysis, the partially guided technique resulted in significantly higher global apical and lateral coronal deviations (2.25 ±0.59 mm; 0.96 ±0.55 mm) than fully guided (1.52 ±0.89 mm; 0.75 ±0.52 mm) (P<.01 and P<.05, respectively). The analysis performed using digital scanning showed significantly higher angular, global apical, and lateral apical deviations in the partially guided (6 ±3.28 degrees; 2.49 ±1.03 mm; 2.16 ±1.07 mm) technique than in the fully guided (3.32 ±1.84 degrees; 1.5 ±0.58 mm; 0.98 ±0.67 mm) (P<.05). An ICC of 0.522 between the 2 methods of implant deviation analysis was obtained. CONCLUSIONS: The partially guided technique was less accurate than the fully guided technique for immediate implant placement into fresh sockets. A moderate concordance was observed between cone beam computed tomography and digital scanning analyses, suggesting that more studies are required to validate and to define the most reliable method of measuring implant deviation.

Presence and predominance of histological grade 3 define cT1HG bladder cancer prognostic groups.

PURPOSE: Current World Health Organization/International Society of Urological Pathology (2004 WHO/ISUP) grading of bladder urothelial carcinoma relies on the highest pathologic grade of the specimen and does not reflect the inherent qualitative and quantitative heterogeneity of disease. MATERIALS AND METHODS: We retrospectively studied consecutive urothelial high-grade cT1 (cT1HG) carcinomas submitted to adjuvant bacille Calmette-Guérin between 2008 and 2015 to evaluate the prognostic potential of grade 3 (presence or predominance) according to the 1973 WHO system concerning disease progression and cancer-specific death. RESULTS: Among 253 patients, grading distribution was 34.4% 1+2, 7.5% 2+1, 20.2% 2+2, 19.0% 2+3, 5.1% 3+2, and 13.8% 3+3. Recurrence was diagnosed in 115 (45.5%), progression in 83 (32.8%), and cancer-specific death in 50 patients (19.8%). Mean time to recurrence, progression, and death from disease were 35.9±31.7, 47.6±44.5, and 51.2±50.4 months, respectively. Grade 3 presence (2+3, 3+2, or 3+3) occurred in 96 (37.9%) and independently predicted time to progression (p<0.001; hazard ratio [HR], 3.11; 95% confidence interval [CI], 1.88-5.14). Grade 3 predominance (3+2 or 3+3) occurred in 48 (18.9%) and independently predicted time to disease-specific death. CONCLUSIONS: Grade 3 presence and predominance are independent predictors of progression and disease-specific death and occur in about 40% and 20% of cT1HG, respectively. Describing qualitative and quantitative heterogeneity in urothelial carcinoma grading might improve the stratification of patients. This gives three prognostic high-grade groups based on WHO/ISUP 1973: prognostic grade group I (grade 3 absence), prognostic grade group II (grade 3 presence), and prognostic grade group III (grade 3 predominance).

The Impact of Surgical Guide Fixation and Implant Location on Accuracy of Static Computer-Assisted Implant Surgery.

PURPOSE: To evaluate the accuracy of static computer-assisted implant surgery (sCAIS) for tooth-supported free-end dental implantation with the aid/and without the aid of fixation pins to secure the surgical template through comparison between planned, 3D printed guide position and placement implant position. MATERIALS AND METHODS: Thirty-two duplicated maxillary resin models were used in the present in vitro study. Digital planning was performed and fabrication of a surgical template that allowed implant placement on the distal extension edentulous site of the model (maxillary left side). A first optical scan was performed after fitting the surgical template on the model to assess the deviation at the surgical guide level. After placing implants in the model using the surgical guide, scan bodies were attached to the implants, and a second scan was performed to record the position of placed implants. The digital representations were later superimposed to the pre-operative scan and measurements of implant deviations were performed. Global (coronal and apical), horizontal (coronal and apical), depth and angular deviations were recorded between planned implant position, guide position, and placement implant position. Three-way ANOVA was used to compare implant location (#13, 14, and 15), fixation pin (with or without pin), and guide comparison (planned, guided, and placement). RESULTS: Final implant placement based on the digital plan and based on the 3D printed guide were very similar except for depth deviation. Use of fixation pin had a statistically significant effect on the depth and angular deviation. Overall, without fixation pins and based on guide versus placement, mean global coronal (0.88 ± 0.36 mm), horizontal coronal (0.55 ± 0.32 mm), and apical (1.44 ± 0.75 mm), and angular deviations (4.28 ± 2.01°) were similar to deviations with fixation pins: mean global coronal (0.88 ± 0.36 mm); horizontal coronal (0.67 ± 0.22 mm) and apical (1.60 ± 0.69 mm); and angular deviations (4.53 ± 2.04°). Horizontal apical without pins (1.63 ± 0.69 mm) and with fixation pins (1.72 ± 0.70 mm) was statistically significant (p = 0.044). Depth deviation without pins (-0.5 ± 0.5 mm) and with fixation pins (-0.16 ± 0.62 mm) was also statistically significant (p = 0.005). Further analysis demonstrated that the final sleeve position on the 3D printed guide was on average 0.5 mm more coronal than the digital plan. CONCLUSIONS: The use of surgical guides with or without fixation pins can provide clinically acceptable outcomes in terms of accuracy in implant position. There was a statistically significant difference in the accuracy of implant position when utilizing fixation pins only for horizontal apical and depth deviation. Additionally, a statistically significant difference between the planned and the 3D printed surgical guide when considering the sleeve position was detected.

Nanoscale hybrid implant surfaces and Osterix-mediated osseointegration.

Endosseous implant surface topography directly affects adherent cell responses following implantation. The aim of this study was to examine the impact of nanoscale topographic modification of titanium implants on Osterix gene expression since this gene has been reported as key factor for bone formation. Titanium implants with smooth and nanoscale topographies were implanted in the femurs of Osterix-Cherry mice for 1-21 days. Implant integration was evaluated using scanning electron microscopy (SEM) to evaluate cell adhesion on implant surfaces, histology, and nanotomography (NanoCT) to observe and quantify the formed bone-to-implant interface, flow cytometry to quantify of Osterix expressing cells in adjacent tissues, and real-time PCR (qPCR) to quantify the osteoinductive and osteogenic gene expression of the implant-adherent cells. SEM revealed topography-dependent adhesion of cells at early timepoints. NanoCT demonstrated greater bone formation at nanoscale implants and interfacial osteogenesis was confirmed histologically at 7 and 14 days for both smooth and nanosurface implants. Flow cytometry revealed greater numbers of Osterix positive cells in femurs implanted with nanoscale versus smooth implants. Compared to smooth surface implants, nanoscale surface adherent cells expressed higher levels of Osterix (Osx), Alkaline phosphatase (Alp), Paired related homeobox (Prx1), Dentin matrix protein 1 (Dmp1), Bone sialoprotein (Bsp), and Osteocalcin (Ocn). In conclusion, nanoscale surface implants demonstrated greater bone formation associated with higher levels of Osterix expression over the 21-day healing period with direct evidence of surface-associated gene regulation involving a nanoscale-mediated osteoinductive pathway that utilizes Osterix to direct adherent cell osteoinduction.

Influence of operator experience, scanner type, and scan size on 3D scans.

STATEMENT OF PROBLEM: Intraoral scanners (IOSs) have some inherent distortions caused by optical and/or software imperfections. However, how other factors such as operator experience, scan time, scanner type, and scan size influence scan accuracy is not clear. PURPOSE: The purpose of this in vitro study was to evaluate the trueness and precision of scans performed by 3 professionals with different levels of experience by using 2 IOSs. MATERIAL AND METHODS: Three operators with low, medium, and high levels of experience scanned a master model 10 times by using 2 IOSs (CEREC Omnicam; Dentsply Sirona and TRIOS 3; 3Shape), resulting in 10 standard tessellation language files for each group (N=60). Each standard tessellation language file was divided into 2 areas (prepared teeth and complete arch). Precision was evaluated by comparing the 10 scans from each examiner for each system. Trueness was evaluated by comparing each scan file with a reference scan obtained from a laboratory scanner (D2000; 3Shape). A 3D analysis software program (Geomagic Control; 3D Systems) was used to perform all the comparisons and superimpositions. The 3-way ANOVA test followed by the Tukey HSD test were used to assess precision and trueness. The 2-way ANOVA followed by the Tukey HSD test was used to assess scan time. The Pearson correlation test was performed between scan time and trueness for both scanners. An additional correlation was performed between scan time and number of images, as well as between number of images and trueness for the TRIOS 3. RESULTS: Statistically significant influences of operator (P<.001), scanner (P<.001), scan size (P<.001), operator and scan size (P<.001), and scanner and scan size (P<.001) were observed. The TRIOS 3 group reported higher precision than the CEREC Omnicam group for complete-arch scans (P<.001), although no difference was observed for scans of the prepared tooth. Medium- (P=.002) and low-experience operators (P<.001) reported lower precision for complete-arch scans performed with CEREC Omnicam when compared with TRIOS 3. The low-experience operator reported significantly worse results for complete-arch scans in comparison with the medium- (P=.008 and P<.001) and high-experience operators (P<.001 and P=.001), by using TRIOS 3 and CEREC Omnicam, respectively. Medium- and high-experience operators reported similar results among themselves. The CEREC Omnicam scanner reported lower trueness for complete-arch scans when compared with the prepared tooth (P<.001); for TRIOS 3, a difference was only observed for the low-experience operator when compared with the high-experience operator (P<.001). The CEREC Omnicam reported lower trueness than the TRIOS 3, except for the medium-experience operator with the prepared tooth scan. Comparing the trueness between operators and considering the same scanner and scan size, all groups were similar. The low-experience operator had a longer scanning time than the medium- and high-experience operators. For TRIOS 3, the low-experience operator obtained the highest number of images during each scan. CONCLUSIONS: The accuracy of intraoral scans was influenced by operator experience, type of IOSs, and scan size. More experienced operators and smaller scan sizes made for more accurate scans. In addition, more experienced operators made faster scans, and the TRIOS 3 was more accurate than the CEREC Omnicam for complete-arch scans.

Denture scanning technique for computer-guided implant-supported restoration treatment of edentulous patients.

The traditional protocol for guided surgery in a completely edentulous patient is time-consuming, requiring the fabrication of a radiographic guide and a dual cone beam computed tomography (CBCT) scan. Using intraoral scanners to scan the edentulous ridge and the existing denture has been advocated to simplify the process. This technique offers a versatile, precise, and predictable method for the digital planning workflow in edentulous patients for either a fixed or removable restoration. In addition, this approach can help improve the quality of the guide produced by reducing CBCT artifacts associated with the existing denture, as well as capture the soft-tissue contour to further improve the fit of the surgical guide.

Electrical stimulation enhances early palatal wound healing in mice.

BACKGROUND/OBJECTIVE: Electrical stimulation (ES) has been used to treat chronic wound and other clinical applications, showing favorable results in wound closure. It was hypothesized that ES can present a positive effect on oral mucosa healing. The aim of this study was to investigate the effects of ES during the palatal mucosa early healing process in Swiss mice. METHODS: Ninety animals were divided into two groups: Control (C; n = 45), which received Sham ES applications, and Test (ES; n = 45), which received ES (100 µA; 9 kHz; 660 mVpp) once a day for 3 days. A full thickness wound was performed with a 1.5 mm diameter biopsy punch in the hard palate. Histologically, the following parameters were evaluated: palatal wound closure and epithelial and connective wound edge distance (EED and CED). Furthermore, IL-1ß, IL-6, IL-10 TNF-α, and VEGF cytokine levels were evaluated by multiplex assay. The percentage of collagen fibers was assessed using the polarization method and the Smad proteins using the immunofluorescence method. RESULTS: Palatal wound closure presented a significant reduction on day 5 in the ES group (p = 0.01). Additionally, both EED and CED were shorter for all time points in the ES group (p < 0.05), and the inflammatory markers IL-6, IL-10, TNF-α, and VEGF were reduced (p < 0.05). There were no differences in collagen fibers and phospho-Smad2 between the groups. CONCLUSION: ES had a positive effect on early palatal wound closure outcomes, as well as on inflammatory markers.

Influence of Titanium Alloy Scaffolds on Enzymatic Defense against Oxidative Stress and Bone Marrow Cell Differentiation.

Studies have been directed towards the production of new titanium alloys, aiming for the replacement of Ti-6 Aluminium-4 Vanadium (TiAlV) alloy in the future. Many mechanisms related to biocompatibility and chemical characteristics have been studied in the field of implantology, but enzymatic defenses against oxidative stress remain underexplored. Bone marrow stromal cells have been explored as source of cells, which have the potential to differentiate into osteoblasts and therefore could be used as cells-based therapy. The objective of this study was to evaluate the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in porous scaffolds of Ti-6 Aluminium-4 Vanadium (TiAlV), Ti-35 Niobium (TiNb), and Ti-35 Niobium-7 Zirconium-5 Tantalum (TiNbZrTa) on mouse bone marrow stromal cells. Porous titanium alloy scaffolds were prepared by powder metallurgy. After 24 hours, cells plated on the scaffolds were analyzed by scanning electron microscopy (SEM). The antioxidant enzyme activity was measured 72 hours after cell plating. Quantitative real time PCR (qRT-PCR) was performed after 3, 7, and 14 days, and Runx2 (Runt-related transcription factor2) expression was evaluated. The SEM images showed the presence of interconnected pores and growth, adhesion, and cell spreading in the 3 scaffolds. Although differences were noted for SOD and CAT activity for all scaffolds analyzed, no statistical differences were observed (p > 0.05). The osteogenic gene Runx2 presented high expression levels for TiNbZrTa at day 7, compared to the control group (TiAlV day 3). At day 14, all scaffolds had more than 2-fold induction for Runx2 mRNA levels, with statistically significant differences compared to the control group. Even though we were not able to confirm statistically significant differences to justify the replacement of TiAlV regarding antioxidant enzymes, TiNbZrTa was able to induce faster bone formation at early time points, making it a good choice for biomedical and tissue bioengineering applications.

In vitro osteogenesis process induced by hybrid nanohydroxyapatite/graphene nanoribbons composites.

Carbon nanotubes combine high bend and mechanical strength, which is advantageous for many structural and biomedical purposes. Recently, some biomaterials, based on carbon nanostructures and nanohydroxyapatite (nHAp), have been investigated as bone substitutes in order to improve regeneration. The aim of this study was to access the expression of some RNA transcripts (involved in the process of osteoblast differentiation) by mesenchymal stem cells cultured over different nanocomposite surfaces. A multi-walled carbon nanotube (MWCNT) was firstly grown using chemical vapor deposition and then exfoliated using chemical and oxygen plasma treatments to obtain graphene nanoribbons (GNR). The hybrid composites nHAp/GNR were prepared using the wet method assisted by ultrasound irradiation with different amounts of GNR (1.0, 2.0 and 3.0 wt %). Five groups were tested in cell cultures. Group 1: synthesized nHAp; Group 2: synthesized GNR; Group 3: nHAp and 1.0% of GNR; Group 4: nHAp and 2.0% of GNR and group 5: nHAp and 3.0% of GNR. Real time reverse transcription polymerase chain reactions were performed, and all data was submitted to Kruskal Wallis and Dunn tests, at a significance level of 5%. As a result, three nanocomposites with different proportions of GNR were successfully produced. After cell culture, the expression of osteogenic genes demonstrated no significant differences among the groups and periods. However, bone morphogenetic protein II (BMP II), integrin binding sialoprotein (IBSP), and Osterix highest expressions were observed in the group containing 3.0% of GNR. In conclusion, our hybrid composites may be useful in bone interventions requiring mesenchymal stem cell differentiation into osteoblasts for healing.

Evaluation of lettuce chloroplast and soybean cotyledon as platforms for production of functional bone morphogenetic protein 2.

The bone morphogenetic protein BMP2 plays a crucial role in the formation and regeneration of bone and cartilage, which is critical for maintaining skeletal integrity and bone fracture repair. Because of its important role in osteogenic properties it has been commercially produced for clinical use. Here we report attempts to express human BMP2 using two plant systems (lettuce chloroplast and soybean seeds). The rhBMP2 gene (coding for the 13 kDa active polypeptide) was introduced in two regions of the lettuce chloroplast genome. Two homoplasmic events were achieved and RT-PCR demonstrated that the BMP2 gene was transcribed. However, it was not possible to detect accumulation of rhBMP2 in leaves. Two soybean events were achieved to express a full-length hBMP2 gene (coding for the 45 kDa pro-BMP2) fused with the α-coixin signal peptide, under control of the ß-conglycinin promoter. Pro-BMP2 was expressed in the transgenic seeds at levels of up to 9.28% of the total soluble seed protein as determined by ELISA. It was demonstrated that this recombinant form was biologically active upon administration to C2C12 cell cultures, because it was able to induce an osteogenic cascade, as observed by the enhanced expression of SP7 (osterix) and ALPI (alkaline phosphatase) genes. Collectively, these results corroborated our previous observation that soybean seeds provide an effective strategy for achieving stable accumulation of functional therapeutic proteins, such as BMP2.

Prognostic impact of non-adherence to follow-up cystoscopy in non-muscle-invasive bladder cancer (NMIBC).

PURPOSE: To evaluate the underexplored context of cystoscopy adherent versus non-adherent patients in the follow-up of urothelial high-risk non-muscle-invasive bladder cancer (NMIBC). METHODS: We performed a retrospective study (2005-2016) that evaluated patients´ demographical characteristics, histopathological data, recurrence, progression and cancer-specific mortality between adherent and non-adherents patients in the first 3 years of a proposed cystoscopy protocol. RESULTS: Among the 198 included patients, comparing cystoscopy non-adherent (n = 36, 18%) and adherent patients (n = 162, 82%), there was no demographic or histopathological differences; the rates of disease recurrence, progression and cancer-specific mortality were 15 (41.7%) versus 68 (42.2%), p = 0.58; 12 (33.3%) versus 28 (17.9%), p = 0.014 and 4 (11.1%) versus 19 (11.7%), p = 0.98, respectively. Cystoscopy non-adherence was associated with an inferior number of urinary cytology (p < 0.001) and 2.33 HR for cancer progression, p = 0.014, (95% CI 1.18-4.59). CONCLUSIONS: Non-adherence to follow-up cystoscopy in NMIBC is associated with more than twice progression risk. Future studies are needed to confirm our results and correlate cystoscopy non-adherence to other covariates.

Shrinkage stress and elastic modulus assessment of bulk-fill composites.

Bulk-fill composites were introduced in dentistry to accelerate clinical procedures while providing adequate outcomes. Concerns regarding the use of bigger composite increments rely on the polymerization shrinkage and shrinkage stress, which may generate gaps on the adhesive interface and result in a reduced success rate. OBJECTIVE: To evaluate the polymerization shrinkage stress of different bulk-fill resin composites and their elastic modulus. MATERIALS AND METHODS: Fourteen specimens were made for each of the nine different resin composites (seven with 12 mm3 and seven with 24 mm3): Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF), Filtek Z350XT Flow (Z3F); Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Xtra Fusion (ADM) and Filtek Z350 XT (Z3XT). Linear shrinkage stress was evaluated for 300 s with the aid of a linear shrinkage device adapted to a Universal Testing Machine. For each composite group, seven additional specimens (2x2x25 mm) were made and Young's modulus was evaluated with a 3-point bending device adapted in a Universal Testing Machine with 0.5 mm/min crosshead speed and 50 KgF loading cell. RESULTS: For 12 mm3 specimens, three-way ANOVA showed that only SDR and TBF generated lower stress after 20 s. Considering 300 s, TBF, SDR, and XF generated the lowest stress, followed by ADM, FBP, XB, and FBF, which were similar to Z3XT. Z3F generated the highest stress values for all time points. Considering 24 mm3 specimens after 20 s, all bulk fill composites generated lower stress than Z3XT, except XB. After 300 s, SDR, FBP, and ADM generated the lowest stress, followed by TBF and XF. For elastic modulus, one-way ANOVA showed that FBF, SDR, Z3F, and ADM presented the lowest values, followed by XB and TBF. FBP, Z3XT, and XF presented the highest elastic modulus among the evaluated composites. CONCLUSIONS: Bulk-fill resin composites presented equal to lower shrinkage stress generation when compared to conventional composites, especially when bigger increments were evaluated. Bulk-fill composites showed a wide range of elastic modulus values, but usually similar to "regular" composites.