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Objectives: to evaluate the morphological and functional characteristics of the peri-implant bone tissue that was formed during the healing process by the placement implants using two different surface treatments: hydrophilic Acqua™ (ACQ) and rough NeoPoros™ (NEO), in spontaneously hypertensive (SHR) and normotensive rats (Wistar) whether or not treated with losartan., Methodology: In total, 96 male rats (48 Wistar and 48 SHR) were divided into eight subgroups: absolute control rough (COA NEO), absolute control hydrophilic (COA ACQ), losartan control rough (COL NEO), losartan control hydrophilic (COL ACQ), SHR absolute rough (SHR NEO), SHR absolute hydrophilic (SHR ACQ), SHR losartan rough (SHRL NEO), and SHR losartan hydrophilic (SHRL ACQ). The rats medicated with losartan received daily doses of the medication. NeoPoros™ and Acqua™ implants were installed in the tibiae of the rats. After 14 and 42 days of the surgery, the fluorochromes calcein and alizarin were injected in the rats. The animals were euthanized 67 days after treatment. The collected samples were analyzed by immunohistochemistry, biomechanics, microcomputerized tomography, and laser confocal scanning microscopy analysis., Results: The osteocalcin (OC) and vascular endothelium growth factor (VEGF) proteins had moderate expression in the SHRL ACQ subgroup. The same subgroup also had the highest implant removal torque. Regarding microarchitectural characteristics, a greater number of trabeculae was noted in the control animals that were treated with losartan. In the bone mineralization activity, it was observed that the Acqua™ surface triggered higher values of MAR (mineral apposition rate) in the COA, COL, and SHRL groups (p<0.05)., Conclusion: the two implant surface types showed similar responses regarding the characteristics of the peri-implant bone tissue, even though the ACQ surface seems to improve the early stages of osseointegration.

We examined the effect of a nanoscale titanium surface topography (D) versus two hybrid micro/nanoscale topographies (B and OS) on adherent mesenchymal stem cells (MSCs) and bone marrow derived macrophages (BMMs) function in cell culture and in vivo. In the in vitro study, compared to OS and B surfaces, D surface induced earlier and greater cell spreading, and earlier and profound mRNA expression of RUNX2, Osterix and BMP2 in MSCs. D surface induced earlier and higher expression of RUNX2 and BMP2 and lower expression of inflammatory genes in implant adherent cells in vivo. Measurement of osteogenesis at implant surfaces showed greater bone-to-implant contact at D versus OS surfaces after 21 days. We explored the cell population on the D and OS implant surfaces 24 h after placement using single-cell RNA sequencing and identified distinct cell clusters including macrophages, neutrophils and B cells. D surface induced lower expression and earlier reduction of inflammatory genes expression in BMMs in vitro. BMMs on D, B and OS surfaces demonstrated a marked increase of BMP2 expression after 1 and 3 days, and this increase was significantly higher on D surface at day 3. Our data implicates a dynamic process that may be influenced by nanotopography at multiple stages of osseointegration including initial immunomodulation, recruitment of MSCs and later osteoblastic differentiation leading to bone matrix production and mineralization. The results suggest that a nanoscale topography (D) favorably modulates adherent macrophage polarization toward anti-inflammatory and regenerative phenotypes and promotes the osteoinductive phenotype of adherent mesenchymal stem cells. STATEMENT OF SIGNIFICANCE: Our manuscript contains original data developed to define effects of a novel nanotopography on the process of osseointegration at the cell and tissue level.  Few studies have compared the effects of a nanoscale surface versus the more typical hybrid micro/nano-scale surfaces used today. We have utilized single-cell RNA sequencing for the first time to identify earliest cell populations on implant surfaces in vivo. We provide data indicating that the nanoscale surface acts upon both osteoprogenitor and immune cell (macrophages) to alter the process of bone formation in a surface-specific manner. This work represents new observations regarding osseointegration and immunomodulation., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: LFC receives research grants and honorarium from Denstply Sirona. Other authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

(1) Background: The objective of this study was to evaluate the morphometry of peri-implant bone tissue in orchiectomized rats, treated with vitamin D isolated or associated with teriparatide. (2) Methods: 24 rats were divided into 4 groups: ORQ-orchiectomy, without drug treatment, ORQ+D-orchiectomy, treated with vitamin D, ORQTERI-orchiectomy, treated with teriparatide and ORQTERI+D-orchiectomy, treated with teriparatide + vitamin D. Each animal received an implant in the tibial metaphysis. Euthanasia occurred 60 days after implant surgery. Computed microtomography (micro-CT) was performed to evaluate the parameters of volume and percentage of bone volume (BV, BV/TV), trabecular thickness (Tb.Th), number and separation of trabeculae (Tb.N, Tb.Sp) and percentage of total porosity (Po-tot). Data were subjected to 1-way ANOVA and Tukey post-test, with a significance level of 5%. (3) Results: For the parameters BV, BV/TV, Tb.Th, the ORQTERI+D group showed the highest values in relation to the other groups and for Po-tot, the lowest values were for ORQTERI+D. For Tb.Sp and Tb.N, there was no statistically significant difference when comparing intragroup results ( p > 0.05). (4) Conclusions: It was possible to conclude that treatment with vitamin D associated with teriparatide increases bone volume and improves bone quality.

The objective of this work was to investigate the use of Biogran® functionalized with parathyroid hormone (PTH) 1-34 by sonochemistry for the local delivery of this anabolic agent to the implant site. The effects of Biogran® and topical administration of PTH 1-34 on peri-implant bone regeneration were evaluated from the microscale to ultrastructural levels in healthy (SHAM) and orchiectomized (ORQ). While some animals only received a titanium implant in their tibial metaphyses (CLOT group), in others the peri-implant defect was first filled with Biogran® either without or with PTH 1-34 functionalization (BG and BGPTH groups, respectively) prior to implant installation. Osseointegration was characterized from a biomechanical perspective by measuring the removal torque with the counter-torque technique. Micro-CT was used to evaluate the percentage of bone volume, trabecular thickness, number and separation, and bone-implant contact (BIC). Dynamics of new bone formation were assessed by measuring fluorochrome area, daily mineral apposition rate, and neoformed bone area using confocal laser microscopy. RT-PCR was performed to evaluate ALP and osteocalcin expression. The interface between newly formed bone and Biogran® was examined using scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) at the micro-and nanoscale, respectively, while elemental analyses were completed in SEM with energy-dispersive X-ray spectroscopy (EDS). STEM imaging demonstrated the intimate attachment of bone to Biogran® (nanoscale level). Overall, the results suggest that the effectiveness of the topical administration of PTH 1-34 at the implant site seems enhanced in osteoporotic bone, promoting peri-implant bone regeneration to comparable levels in healthy conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

(1) Background: There are many therapies for osteoporosis control and bone maintenance; anabolic drugs such as teriparatide and bone grafts help in the repair process and stimulate bone formation. Thus, the aim of the present study was to evaluate the behavior of repaired bone in the presence of PTH (teriparatide) associated with Biogran ® (biomaterial) through a sonochemical procedure after extraction in rats. (2) Methods: The insertion of Biogran ® with PTH in the alveolus was performed 30 days after incisor extraction. Euthanasia occurred after 60 days. (3) Results: The use of local treatment of PTH loaded with Biogran® in healthy rats promoted good results for micro-CT, with an increase in percentage and bone volume, number and trabecular separation and less total porosity. Greater immunostaining for Wnt, β-Catenin and osteocalcin proteins and lower expression for Thrombospondin-Related Adhesive Protein (TRAP), which shows an increase in the number of osteoblasts and inhibition of osteoclast action. However, the treated orchiectomized groups did not obtain such expressive results. (4) Conclusion: The use of Biogran ® with PTH improved alveolar repair in rats. However, new researches with more efficient doses must be studied to collaborate effectively with the formation of a quality bone after the orchiectomy.

The success of biomaterials for bone regeneration relies on many factors, among which osseointegration plays a key role. Biogran (BG) is a bioactive glass commonly employed as a bone graft in dental procedures. Despite its use in clinical practice, the capability of BG to promote osseointegration has never been resolved at the nanoscale. In this paper, we present the workflow for characterizing the interface between newly formed bone and BG in a preclinical rat model. Areas of bone-BG contact were first identified by backscattered electron imaging in a scanning electron microscope. A focused ion beam in situ lift-out protocol was employed to prepare ultrathin samples for transmission electron microscopy analysis. The bone-BG gradual interface, i.e. the biointerphase, was visualized at the nanoscale with unprecedented resolution thanks to scanning transmission electron microscopy. Finally, we present a method to view the bone-BG interface in three dimensions using electron tomography.

The aim of this study was to analyze the stages of the alveolar bone repair in type 2 diabetic rats evaluating the mechanism of mineralization and bone remodeling processes after dental extraction. Forty-eight rats were divided into normoglycemic (NG) and type 2 diabetes (T2D) groups. The upper right incisor was extracted and after 3, 7, 14 and 42 days the animals were euthanized. The following analyses were performed: immunolabeling against antibodies TNFα, TGFβ, IL6, WNT, OCN and TRAP, collagen fibers maturation, microtomography and confocal microscopy. Data were submitted to statistical analysis. The immunolabeling analysis showed that the T2D presented a more pronounced alveolar inflammation than NG. Labeling of proteins responsible for bone formation and mineralization was higher in NG than T2D, which presented greater resorptive activity characterized by TRAP labeling. Also, T2D group showed a decrease in the amount of collagen fibers. Micro-CT analysis showed that T2D causes a decrease in bone volume percentage due to deficient trabecular parameters and higher porosity. The T2D bone dynamics show a loss in bone remodeling process. T2D prolongs the local inflammatory process, which impairs the organization and maturation of collagen fibers, delaying bone formation that generates impact on mineralization and bone turnover.

This study evaluated the peri-implant bone repair in orchiectomized rats receiving intermittently PTH 1-34. The treatment returned the bone quality and quantity of the animals to normal in the computerized microtomography, laser confocal microscopy, and histological analysis. The PTH 1-34 promoted marked bone formation with increased volume, improved quality, and greater bone turnover., Introduction: Osteoporosis can be a problem in implant osseointegration. So this study aimed to evaluate the quantity and quality of peri-implant bone repair in orchiectomized Wistar rats receiving intermittently administered PTH 1-34., Methods: Animals (n = 24) were divided into 3 groups: healthy control (SHAM), orchiectomized (ORQ), and orchiectomized and treated with 0.5 μg/kg/day PTH 1-34 (TERI), and each received an implant in the right and left tibial metaphysis, which was allowed to repair for 60 days. The resultant bone formation was evaluated through computerized microtomography (micro-CT) to compare the percent bone volume (BV/TV), trabecular thickness (Tb.Th), trabecular number and separation (Tb.N, Tb.Sp), and bone implant contact (BIC) through the intersection surface (i.S) between groups. Laser confocal microscopy was used to evaluate fluorochrome areas for mineral apposition rate (MAR) and neoformed bone area (NBA). In addition, histological evaluation of calcified tissues with Stevenel blue and alizarin red staining was performed., Results: Treatment with PTH 1-34 returned the bone quality and quantity of the osteoporotic animal to normal, as the TERI group presented statistically significant higher values for BV/TV, Tb.Th, and BIC parameters compared with ORQ (p < 0.05), but when compared with SHAM (p > 0.05), no statistical difference was noted. In addition, in the bone turnover analysis (MAR, NBA) for TERI, the highest results are presented, followed by SHAM, and then ORQ (TERI × ORQ: p < 0.05)., Conclusions: Intermittent treatment with PTH 1-34 on orchiectomized animals promoted marked bone formation with increased volume, improved quality, and greater bone turnover in the peri-implant space, returning the bone quality and quantity to the present standard in healthy animals.

The aim of this study was determinate the best sonochemical time in order to obtain better bone characteristics when a bioactive material (Biogran) is used in the filling periimplantar defects. In this study, 32 rats were submitted to surgical proceedings to create a periimplantar defect that was filled with Biogran receiving different sonochemical times: 15 (G1), 30 (G2), 45 (G3) or 90 min (G4). The biomaterial was characterized through X-ray diffraction and scanning electron microscopy (SEM). In vivo analysis was performed through micro CT, laser confocal microscopy, immunohistochemistry and evaluation of bone cytoarchitecture through hematoxylin and eosin (HE) staining. The data were submitted to statistical testing, considering a significance level of p < 0.05. Rx diffraction of pure bioglass showed that it is predominantly amorphous; otherwise, there are small peaks at 23° and 31°. SEM shows that the longer the sonochemical time, the less edges the biomaterial will present. Within the groups, G1 and G2 showed the best quantity and quality by micro CT (p > 0.05). The best bone turnover result was found in G1 and G2, otherwise the better results were related to neoformed bone area, bone mineral apposition rate and bone implant contact to G1 (p < 0.05). G1 had the best results in terms of bone cytoarchitectural evaluation and immunohistochemistry. It is possible to conclude that Biogran that received 15 min of sonochemical treatment (G1) presented periimplantar bone repair with the best extracellular matrix properties, including the best quality and quantity of vital bone., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Objective: This study proposes to evaluate, by means of microtomographic analysis, the topical potential of raloxifene combined with BioGran® through the sonochemical method in the repair of critical bone defects in the calvaria of rats. The hypothesis was that the homogenization of Raloxifene to Biogran at the 20% concentration would improve the bone repair at the grafted site., Materials and Methods: A 5-mm calvaria bone defect was induced in three groups: CTR (100% BioGran®); RAL10 (90% BioGran® and 10% raloxifene), and RAL20 (80% BioGran® and 20% raloxifene). The animals were euthanized after 30 days and the microCT analysis was then performed to evaluate the parameters bone volume (BV), bone volume percentage (BV/TV), trabecular bone thickness (Tb.Th), and the separation and number of trabeculae (Tb.Sp and Tb.N). The obtained results were compared using ANOVA and Tukey test (p < 0.05)., Results: The best results were found for the CTR and RAL20 groups, in which the BV, BV/TV, Tb.Sp, and Tb.N parameters were statistically significant in comparison with RAL10 (p < 0.05)., Conclusions: In view of the results obtained in this experiment, we can conclude that BioGran® alone or in an 80/20 mass concentration with raloxifene can lead to favorable bone formation.

Introduction: The hypothesis of this study was that the peri-implant bone healing of the group of pinealectomized rats would differ from the control group. The samples were subjected to immunohistochemical, microtomographic (total porosity and connectivity density), and fluorochrome (mineralized surface) analyses., Objectives: The goal of this study was to investigate the cellular changes and bone remodeling dynamics along the bone/implant interface in pinealectomized rats., Material and Methods: The total of 18 adult male rats (Rattus norvegicus albinus, Wistar) was divided into three groups (n=6): control (CO), pinealectomized without melatonin (PNX) and pinealectomized with melatonin (PNXm). All animals were submitted to the first surgery (pinealectomy), except the CO group. Thirty days after the pinealectomy without melatonin, the second surgery was conducted, in which all animals received an implant in each tibia (36 titanium implants with surface treatment were installed - Implalife® São Paulo, SP, Brazil). By gavage, the rats of the PNX group received the vehicle solution, and the procedure., Results: Immunohistochemical analysis for runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteopontin (OP) and osteocalcin (OC) showed that the bone repair process in the PNXm group was similar to that of the CO group, whereas the PNX group showed a delay. The microtomographic parameters of total porosity [Po(tot)] and bone surface (BS) showed no statistically significant differences, whereas for the connective density (Conn.Dn) a statistical difference was found between the CO and PNXm groups. Fluorochrome analysis of the active mineralized surface showed statistically significant difference between the CO and PNX and between the CO and PNXm groups., Conclusion: The absence of the pineal gland impaired the bone repair process during osseointegration, however the daily melatonin replacement was able to restore this response.

Objective: The aim of this study was to evaluate the osteoconductive potential of BoneCeramic™ on bone healing in rat calvaria 5-mm defects., Material and Methods: A 5-mm calvaria bone defect was induced in three groups and the defect was not filled with biomaterial [Clot Group (CG)], autogenous bone (AG), or Bone Ceramic Group (BCG). Animals were euthanized after 14 or 28 days and the bone tissue within the central area of the bone defect was evaluated. Results were compared using ANOVA and Tukey test (p<0.05). Immunohistochemistry was performed using primary antibodies against osteocalcin, RUNX-2, TRAP, VEGF proteins, and 3-dimensional images of the defects in μCT were obtained to calculate bone mineral density (BMD)., Results: In BCG, the defect was completely filled with biomaterial and new bone formation, which was statistically superior to that in the GC group, at both time-points (p<0.001 for 14 days; p=0.002 for 28 days). TRAP protein showed weak, RUNX-2 showed a greater immunolabeling when compared with other groups, VEGF showed moderate immunostaining, while osteocalcin was present at all time-points analyzed. The μCT images showed filling defect by BCG (BMD= 1337 HU at 28 days)., Conclusion: Therefore, the biomaterial tested was found to be favorable to fill bone defects for the reporting period analyzed.

Infections of the maxillofacial complex caused by caries disease are common in dental practice. The professionals have to have technical knowledge to treat it at the onset of the condition and avoid the spread to deep anatomical spaces of face and neck, which can implicate in a risk of patients' life.In Brazil, current dental professionals usually denied oral surgical treatments in patients with some clinical conditions, not because of fear to resolve it but for lack of knowledge to treat it. An example of these conditionals is pregnancy. It is well known that during the pregnancy period, the patient can be treated in the correct period of gestation. Early diagnosis is crucial for effective therapy in serious infections. The treatment has to be crucial during pregnancy because of the potentially fatal situation that the disease can create to the pregnant woman and the fetus.The aim of this article is to demonstrate a case of dental caries in a pregnant patient, which was evaluated by other professionals and had the treatment denied, evolving to a serious maxillofacial infection.

This study aimed to assess the biological response of BMP-2 (bone morphogenetic protein-2) in supplementation with β-tricalcium phosphate (TCP) as a carrier in the bone healing of surgical defects in rats' calvaria. A critical-size defect (5mm in diameter) was filled with β-TCP alone or added with that plus 5mg of BMP-2 at 5, 15, and 30 postoperative days. Histomorphometric and immunohistochemical (osteocalcin, collagen type I, and metalloproteinase-9) analysis was performed to assess the features of bone healing. Histological behavior and collagen type I labeling showed increased formation of the collagen matrix, leading to a higher percentage of newly formed bone and biomaterial for tissue and more total mineralization of pure TCP when compared to the other groups. The supplementation with BMP-2 promoted faster TCP remodeling; however, there was no statistically significant difference for the bone formed in both groups (P>0.05). Collagen-matrix formation and new bone formation reached maximum levels when the defects were filled with pure TCP, even exceeding the levels from BMP-2 supplementation., (Copyright © 2017 Elsevier GmbH. All rights reserved.)