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AimMethodsResultsConclusionsWe aimed to investigate whether α-ketoglutarate (AKG) can promote autophagic activity under a peri-implant condition to enhance the osseointegration of dental implant in rats with osteoporosis (OP).Con, Model and AKG groups were established for the random allocation of thirty rats (n = 10). Their bone metabolism indicators were measured. The peri-implant bone morphology was detected by toluidine blue staining, the peri-implant bone tissue healing was detected, and the implant torque was measured.In comparison to the Con group, the bone metabolism indicators [bone volume/tissue volume ratio (BV/TV), trabecular number (Tb.N), and osseointegration index (OI)], bone-implant contact (BIC) rate, bone mass in the cancellous area, dislocation torque, protein and mRNA expressions of bone morphogenetic protein-2 (BMP-2), RUNX2 and Beclin1, and LC3II/LC3I ratio in bone tissues decreased significantly in the Model group, with a significant enlargement of trabecular space (Tb.Sp) (p < 0.05). In comparison with the Model group, the AKG group had significant increases in Tb.N, BV/TV, OI, BIC rate, bone mass in the cancellous area, dislocation torque, mRNA plus protein expressions of BMP-2, Runt-related transcription factor 2 and Beclin1, and LC3II/light chain 3I ratio in bone tissues, in addition to a significant reduction of Tb.Sp (p < 0.05).AKG may relieve the bone metabolism disorders and enhance the osteogenic differentiation and osseointegration of implants in OP rats by promoting peri-implant autophagy. [ABSTRACT FROM AUTHOR]

Objective: To assess the effect of topically applied hyaluronic acid (HA) on the stability of immediately loaded implants in the posterior maxilla. Materials and Methods: For the clinical study, a total of 20 implants were placed in 14 patients seeking the replacement of missing single or multiple posterior maxillary teeth. The patients were randomly divided into two groups. In the clinical control group (CC group), 10 implants were placed and immediately loaded, while in the clinical study group (CS group), 10 implants were coated with HA immediately before placement and immediately loaded. All patients had implant stability clinically evaluated at implant placement time (T0) and 1 (T1), 3 (T3), and 6 (T6) months after loading. Peri-implant pocket depth and modified sulcus bleeding index were evaluated clinically at 6 months in all patients. Bone density was evaluated radiographically after 3 months. All the clinical and radiographic data were subjected to statistical analysis. For the animal study, a total of 12 implants were placed in the tibiae of six rabbits. For each rabbit, 1 implant without any applied HA was placed in the left tibia (AC group), and 1 implant coated with HA was placed in the right tibia (AS group). The rabbits were euthanized at 21 and 45 days after implant insertion. Results: There were no significant statistical differences between the two groups regarding implant stability, peri-implant pocket depth, modified sulcus bleeding index, or bone density from the palatal and apical aspects. However, there was a significant statistical difference in the bone density from the buccal aspect in favor of the study group. The animal study showed that the newly formed bone in the right tibiae showed improved quantity and quality of bone, as it had denser bone trabeculae and smaller marrow spaces compared to the left tibiae. Conclusion: In the clinical study, the application of hyaluronic acid had a superior effect on the buccal bone density around immediately loaded implants. In the animal study, hyaluronic acid had a synergistic effect on the quality and quantity of bone formation around dental implants. [ABSTRACT FROM AUTHOR]

Orthopedic and dental implantations under bacterial infection microenvironment face significant challenges in achieving high-quality bone-implant integration. Designing implant coatings that incorporate both immune defense and anti-inflammation is difficult in conventional single-functional coatings. We introduce a multifunctional nanointerface using a zinc finger-inspired peptide-metal-phenolic nanocoating, designed to enhance implant osseointegration under such conditions. Abaloparatide (ABL), a second-generation anabolic drug for treating osteoporosis, can be integrated into the design of a zinc-phenolic network constructed on the implant surface (ABL@ZnTA). Importantly, the phenolic-coordinated Zn2+ ions in ABL@ZnTA can act as zinc finger motif to co-stabilize the configuration of ABL through multiple molecular interactions, enabling high bioactivity, high loading capacity (1.36 times), and long-term release (>7 days) of ABL. Our results showed that ABL@ZnTA can modulate macrophage polarization from the pro-inflammatory M1 towards the anti-inflammatory M2 phenotype, promoting immune osteogenesis with increased OCN, ALP, and SOD 1 expression. Furthermore, the ABL@ZnTA significantly reduces inflammatory fibrous tissue encapsulation and enhances the long-term stability of the implants, indicated by enhanced binding strength (6 times) and functional connectivity (1.5−3 times) in the rat bone defect model infected by S. aureus. Overall, our research offers a nano-enabled synergistic strategy that balances infection defense and osteogenesis promotion in orthopedic and dental implantations.

Introduction: Percutaneous Osseointegrated Implants (POIs) influence the load transfer path to the host bone. In turn, mechano-regulatory processes (strain adaptive bone remodeling) drive periprosthetic bone changes that influence implant stability and fixation outcome. These bone changes have not yet been reported for the Intraosseous Transcutaneous Amputation Prosthesis (ITAP) clinical trial. Objectives: This study will first standardize the zoning and reporting of periprosthetic bone change in POI radiographs. Second, it will retrospectively measure periprosthetic bone change from radiographs of 12 participants with an ITAP up to 11 years. Finally, the results will be qualitatively compared with those from participants with different POI designs. Materials and Methods: Twenty participants with unilateral transfemoral amputations received an ITAP in a 2-center UK clinical trial in either 2008/09 or 2013/14. Participant radiographs from one center were available (n = 12) over 11 years and have been collated and processed in a repeatable way. Transverse plane periprosthetic bone change measurements at 3 equidistant points along the implant stem were measured in AP and ML. Results: Total median bone growth in AP was double that in ML (57.6 mm and 31.12 mm, respectively). Median lateral and posterior bone change (1.44 mm and 1.09 mm) was greater than median medial and anterior (0.83 mm and −0.005 mm) bone changes, respectively. The greatest change in radial bone growth was observed distally and the least proximally. Conclusions: Bone changes were similar to other collared pressfit POIs in the literature. We demonstrate the influence of stem design and mechano-regulatory remodeling in stable fixation; however, additional influences on periprosthetic bone change were inferred from the results and further investigations are necessary. Clinical Relevance: To identify ITAP design features and fixations that minimize endosteal resorption, thus promoting implant stability and contributing to clinical guidelines for rehabilitation and future design and fixation choices. [ABSTRACT FROM AUTHOR]

At present, a lack of consensus exists regarding the clinical impact of osteoporosis on alveolar bone metabolism during implant osseointegration. While limited preclinical and clinical evidence demonstrates a negative influence of osteoporosis on dental extraction socket healing, no preclinical studies offer data on the results of implant placement in 6-mo-old, ovariectomized (OVX) Sprague–Dawley rats. This study aimed to investigate the outcomes of dental tooth extraction socket healing and implant placement in a rodent model of osteoporosis following daily vehicle (VEH) or abaloparatide (ABL) administration. Micro-CT and histologic analysis demonstrated signs of delayed wound healing, consistent with alveolar osteitis in extraction sockets following 42 d of healing in both the VEH and ABL groups. In a semiquantitative histological analysis, the OVX-ABL group demonstrated a tendency for improved socket regeneration with a 3-fold greater rate for moderate socket healing when compared to the OVX-VEH group (43% vs 14%), however, this finding was not statistically significant (p=.11). No significant differences were observed between vehicle and test groups in terms of implant outcomes (BMD and bone volume/total volume) at 14- and 21-d post-implant placement. Abaloparatide (ABL) significantly increased BMD of the femoral shaft and intact maxillary alveolar bone sites in OVX animals, demonstrating the therapeutic potential for oral hard tissue regeneration. The present model involving estrogen-deficiency-induced bone loss demonstrated an impaired healing response to dental extraction and implant installation. Lay Summary: Osteoporosis is a systemic disease that may negatively impact bone healing in the jaws. This study assesses extraction socket healing and dental implant placement in estrogen-deficient animals treated with a bone building drug, abaloparatide, compared to control. Graphical Abstract [ABSTRACT FROM AUTHOR]

Background: Rehabilitation of the edentulous maxilla with dental implants is challenging. The transcrestal sinus elevation procedure has become an important preprosthetic surgical procedure for bone creation in the posterior maxilla with implant placement. Purpose: This study was planned to evaluate the success of transcrestal sinus elevation using a simple lift kit with simultaneous grafting and placement of implant. Patients and methods: A randomized clinical trial was conducted on ten patients with bone height below the floor of the maxillary sinus ranged from 5 to 8 mm, which was indicated for sinus membrane elevation using the simple lift kit. After preparation of the implant site and osteotomy, sinus membrane elevation using the simple lift kit and augmentation using bovine bone with the implant placement using surgical guide were done simultaneously. Osseointegration and bone height were measured using cone beam computed tomography after 6 months. Results: Successful sinus membrane grafting using simple lift kit procedures was performed in 10 cases without sinus membrane perforation. A total of 10 implants were placed. The radiographic examination showed the bone height before and after sinus membrane lift was statistically significant, as there the increase in bone height ranged from 2.4 to 4.8 mm. Conclusion: The simple lift kit is a minimally invasive technique, associated with very little discomfort and complications, which allows greater control and safety when performing the elevation of the sinus membrane. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the optimization of computer-aided design/computer-aided manufacturing (CAD/CAM) patient-specific implants for mandibular facial bone defects and compare the biocompatibility and osseointegration of machined titanium (Ma), Sandblasted/Large-grit/Acid-etched (SLA) titanium, and polyetherketoneketone (PEKK) facial implants. We hypothesized that the facial implants made of SLA titanium had superior osseointegration when applied to the gonial angle defect and prevented the senile atrophy of the bone. Histologic findings of the soft-tissue reaction, hard-tissue reaction, and bone–implant contact (BIC (%) of 24 Ma, SLA, and PEKK facial implants at 8 and 12 weeks were investigated. There was no statistical difference in the soft tissue reaction. Bone was formed below the periosteum in all facial implants at 12 weeks and the BIC values were significantly different at both 8 and 12 weeks (p < 0.05). Ma, SLA, and PEKK facial implants are biocompatible with osseointegration properties. SLA can enhance osseointegration and provoke minimal soft tissue reactions, making them the most suitable choice. They provide an excellent environment for bone regeneration and, over the long term, may prevent atrophy caused by an aging mandible. The bone formation between the lateral surface of the facial implant and periosteum may assist in osseointegration and stabilization. [ABSTRACT FROM AUTHOR]

Currently available focal knee resurfacing implants (FKRIs) are fully or partially composed of metals, which show a large disparity in elastic modulus relative to bone and cartilage tissue. Although titanium is known for its excellent osseointegration, the application in FKRIs can lead to potential stress‐shielding and metal implants can cause degeneration of the opposing articulating cartilage due to the high resulting contact stresses. Furthermore, metal implants do not allow for follow‐up using magnetic resonance imaging (MRI).To overcome the drawbacks of using metal based FKRIs, a biomimetic and MRI compatible bi‐layered non‐resorbable thermoplastic polycarbonate‐urethane (PCU)‐based FKRI was developed. The objective of this preclinical study was to evaluate the mechanical properties, biocompatibility and osteoconduction of a novel Bionate® 75D ‐ zirconium oxide (B75D‐ZrO2) composite material in vitro and the osseointegration of a B75D‐ZrO2 composite stem PCU implant in a caprine animal model. The tensile strength and elastic modulus of the B75D‐ZrO2 composite were characterized through in vitro mechanical tests under ambient and physiological conditions. In vitro biocompatibility and osteoconductivity were evaluated by exposing human mesenchymal stem cells to the B75D‐ZrO2 composite and culturing the cells under osteogenic conditions. Cell activity and mineralization were assessed and compared to Bionate® 75D (B75D) and titanium disks. The in vivo osseointegration of implants containing a B75D‐ZrO2 stem was compared to implants with a B75D stem and titanium stem in a caprine large animal model. After a follow‐up of 6 months, bone histomorphometry was performed to assess the bone‐to‐implant contact area (BIC). Mechanical testing showed that the B75D‐ZrO2 composite material possesses an elastic modulus in the range of the elastic modulus reported for trabecular bone. The B75D‐ZrO2 composite material facilitated cell mediated mineralization to a comparable extent as titanium. A significantly higher bone‐to‐implant contact (BIC) score was observed in the B75D‐ZrO2 implants compared to the B75D implants. The BIC of B75D‐ZrO2 implants was not significantly different compared to titanium implants. A biocompatible B75D‐ZrO2 composite approximating the elastic modulus of trabecular bone was developed by compounding B75D with zirconium oxide. In vivo evaluation showed an significant increase of osseointegration for B75D‐ZrO2 composite stem implants compared to B75D polymer stem PCU implants. The osseointegration of B75D‐ZrO2 composite stem PCU implants was not significantly different in comparison to analogous titanium stem metal implants. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the effect of collagen cross-link deficiency on collagen fiber formation around an implant and its effect on the osseointegration process. Methods: Wistar rats were fed 0.1% beta-aminopropionitrile (BAPN) dissolved in water to induce collagen cross-link deficiency. Custom-made mini-implants with machined surfaces were placed proximal to the tibia. At 1, 2, and 4 weeks postoperatively, the bone area around the implant, bone-implant contact ratio, osteoclast/osteocyte activity, and osseointegration strength were evaluated using histological and immunohistochemical analyses and biomechanical tests. Results: Long-term disturbance of collagen cross-link formation in the BAPN group resulted in faster collagen fiber maturation than that in controls, with a defective collagen structure, low bone formation quantity, and low bone-implant contact values. Deficiency of collagen cross-links resulted in increased bone resorption and decreased osteocyte activity. Conclusions: Collagen cross-linking is important for the formation of the collagen matrix, and their deficiency may impair bone activity around implants, affecting the osseointegration process. [ABSTRACT FROM AUTHOR]

Objec&ve: One of the unique tooth or tooth replacement prosthesis in the dental implant. To encourage bone forma&on where it is applied, our approach uses a biomaterial system that is easily obtainable, and able to induce osteoinduc&ve growth factor. Selenium nanopar&cles are Methods: Thirty-two implants consis7ng of commercially pure 7tanium rod were given to sixteen New Zealand rabbits. One implant was placed in each 7bia of each rabbit. AAer implanta7on, eight rabbits were sacrificed every one to six weeks. For each animal, the leA 7bia implant was treated with selenium nanopar7cles, whereas the right 7bia implant was leA uncoated. AAer staining each sec7on with hematoxylin and eosin, the sec7ons were examined histologically and assessed for histomorphometric analysis, which counted the number of bone par7cles that were formed. Results: Selenium nanopar7cle-coated 7tanium implants showed earlier bone growth, mineraliza7on, and matura7on than control comparisons. AAer all the bone parameters were examined histomorphometrically for the study, the healing dura7ons of the two types of implants differed significantly. Conclusion: Selenium nanopar7cle-coated 7tanium implants had improved healing and osseointegra7on. [ABSTRACT FROM AUTHOR]

In recent years, implant treatment has become a popular option and is frequently preferred by patients and doctors. Initial implant stabilization is a vital element for implant-osseointegration and long-term implant success. Salah Huwais conceptualized the osseodensification technique for dental implant placement. Compared to conventional implant osteotomy practices, osseodensification allows a nonsubtractive osteotomy preparation. Specially designed burs are used in a noncutting counterclockwise direction to preserve and condense bone. The present case series aims to explain the implementation of osseodensification for dental implant insertion in the thin bony alveolar process, internal closed sinus elevation with implant placement, and immediate implant insertion in the extraction socket. Three different case reports have been discussed in detail where the osseodensification technique was used with specially designed Densah™ Bur to prepare the osteotomy and simultaneous implant placement. The study also focuses on the technique's advantages, disadvantages, and indications, as existing in the relevant literature, along with evidence. Osseodensification is a unique procedure that prepares implant sites while conserving the alveolar bone. In the present report of three cases, satisfactory primary stability of implants with conservation of alveolus integrity was accomplished, which resulted in a shorter restoration interval for prosthetic rehabilitation. [ABSTRACT FROM AUTHOR]

Objective: One of the unique tooth or tooth replacement prosthesis in the dental implant. To encourage bone formation where it is applied, our approach uses a biomaterial system that is easily obtainable, and able to induce osteoinductive growth factor. Selenium nanoparticles are Methods: Thirty-two implants consisting of commercially pure titanium rod were given to sixteen New Zealand rabbits. One implant was placed in each tibia of each rabbit. After implantation, eight rabbits were sacrificed every one to six weeks. For each animal, the left tibia implant was treated with selenium nanoparticles, whereas the right tibia implant was left uncoated. After staining each section with hematoxylin and eosin, the sections were examined histologically and assessed for histomorphometric analysis, which counted the number of bone particles that were formed. Results: Selenium nanoparticle-coated titanium implants showed earlier bone growth, mineralization, and maturation than control comparisons. After all the bone parameters were examined histomorphometrically for the study, the healing durations of the two types of implants differed significantly. Conclusion: Selenium nanoparticle-coated titanium implants had improved healing and osseointegration.

Vertical bone augmentation to create host bone prior to implant placement is one of the most challenging regenerative procedures. The objective of this study is to evaluate the capacity of a UV-photofunctionalized titanium microfiber scaffold to recruit osteoblasts, generate intra-scaffold bone, and integrate with host bone in a vertical augmentation model with unidirectional, limited blood supply. Scaffolds were fabricated by molding and sintering grade 1 commercially pure titanium microfibers (20 μm diameter) and treated with UVC light (200-280 nm wavelength) emitted from a low-pressure mercury lamp for 20 min immediately before experiments. The scaffolds had an even and dense fiber network with 87% porosity and 20-50 mm inter-fiber distance. Surface carbon reduced from 30% on untreated scaffold to 10% after UV treatment, which corresponded to hydro-repellent to superhydrophilic conversion. Vertical infiltration testing revealed that UV-treated scaffolds absorbed 4-, 14-, and 15-times more blood, water, and glycerol than untreated scaffolds, respectively. In vitro, four-times more osteoblasts attached to UV-treated scaffolds than untreated scaffolds three hours after seeding. On day 2, there were 70% more osteoblasts on UV-treated scaffolds. Fluorescent microscopy visualized confluent osteoblasts on UV-treated microfibers two days after seeding but sparse and separated cells on untreated microfibers. Alkaline phosphatase activity and osteocalcin gene expression were significantly greater in osteoblasts grown on UV-treated microfiber scaffolds. In an in vivo model of vertical augmentation on rat femoral cortical bone, the interfacial strength between innate cortical bone and UV-treated microfiber scaffold after two weeks of healing was double that observed between bone and untreated scaffold. Morphological and chemical analysis confirmed seamless integration of the innate cortical and regenerated bone within microfiber networks for UV-treated scaffolds. These results indicate synergy between titanium microfiber scaffolds and UV photofunctionalization to provide a novel and effective strategy for vertical bone augmentation.

Objective: This study aimed to synthesize zinc‐incorporated nanowires structure modified titanium implant surface (Zn‐NW‐Ti) and explore its superior osteogenic and antibacterial properties in vitro and in vivo. Materials and methods: Zn‐NW‐Ti was synthesized via displacement reactions between zinc sulfate solutions and the titanium (Ti) surface, which was pretreated by hydrofluoric acid etching and hyperthermal alkalinization. The physicochemical properties of the Zn‐NW‐Ti surface were examined. Moreover, the biological effects of Zn‐NW‐Ti on MC3T3‐E1 cells and its antibacterial property against oral pathogenic bacteria (Staphylococcus aureus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) compared with sandblasted and acid‐etched Ti (SLA‐Ti) and nanowires modified Ti (NW‐Ti) surface were assessed. Zn‐NW‐Ti and SLA‐Ti modified implants were inserted into the anterior extraction socket of the rabbit mandible with or without exposure to the mixed bacterial solution (S. aureus, P. gingivalis, and A. actinomycetemcomitans) to investigate the osteointegration and antibacterial performance via radiographic and histomorphometric analysis. Results: The Zn‐NW‐Ti surface was successfully prepared. The resultant titanium surface appeared as a nanowires structure with hydrophilicity, from which zinc ions were released in an effective concentration range. The Zn‐NW‐Ti surface performed better in facilitating the adhesion, proliferation, and differentiation of MC3T3‐E1 cells while inhibiting the colonization of bacteria compared with SLA‐Ti and NW‐Ti surface. The Zn‐NW‐Ti implant exhibited enhanced osseointegration in vivo, which was attributed to increased osteogenic activity and reduced bacterial‐induced inflammation compared with the SLA‐Ti implant. Conclusions: The Zn‐incorporated nanowires structure modified titanium implant surface exhibited improvements in osteogenic and antibacterial properties, which optimized osteointegration in comparison with SLA titanium implant surface. [ABSTRACT FROM AUTHOR]

Accurate quantification of the jawbone-implant interface plays a pivotal role in assessing the mechanical stability of dental implant structures. This study proposes a methodology integrating the electro-mechanical impedance (EMI)-based technique with a deep learning algorithm to autonomously monitor the bone-implant interface during the osseointegration process. We develop a 1D convolutional neural network (1D CNN) model, which automatically processes raw EMI data and extracts optimal features for predicting osseointegration ratios. To validate our approach, we conduct predictive 3D numerical modelling of the PZT-implant-bone system. This model simulates the implant's EMI response under varying degrees of osseointegration. Next, we employ traditional statistical metrics to monitor osseointegration and discuss their limitations. Finally, we apply the proposed 1D CNN model to predict bone-implant osseointegration rate. We train and test the network using the simulated EMI data with added noise to account for real-world conditions. The results show that the trained model achieves a minimal testing error of just 2.4%. Even when 60% of testing cases are not trained, the model maintains a prediction accuracy exceeding 94%. [ABSTRACT FROM AUTHOR]

This study presents a mechanical model of a novel medical device designed to optimize the osseointegration process in upper and lower limb amputees, leading to the promotion of optimal rehabilitation. The medical device is developed to reduce the risk of implant failure, leading to re-amputation above the implant. The proposed model serves several purposes: 1) to guide the osseointegration process by providing electrical endo-stimulation directly to the bone-implant contact site, using an invasive electrical stimulation system, which is implanted in the bone permanently, 2) to locally transmit stem cells after implantation, without the need for opening the skin or perforating the bone, which is particularly useful for regenerative medicine after partial healing of the implant, 3) to transmit necessary nutrients from the bone, also without opening the skin or puncturing the bone, and 4) to combat infections by locally administering drugs after implantation. [ABSTRACT FROM AUTHOR]

Introduction: Electrical stimulation has been used as a promising approach in bone repair for several decades. However, the therapeutic use is hampered by inconsistent results due to a lack of standardized application protocols. Recently, electrical stimulation has been considered for the improvement of the osseointegration of dental and endoprosthetic implants.Methods: In a pilot study, the suitability of a specifically developed device for electrical stimulation in situ was assessed. Here, the impact of alternating electric fields on implant osseointegration was tested in a gap model using New Zealand White Rabbits. Stimulation parameters were transmitted to the device via a radio transceiver, thus allowing for real-time monitoring and, if required, variations of stimulation parameters. The effect of electrical stimulation on implant osseointegration was quantified by the bone-implant contact (BIC) assessed by histomorphometric (2D) and µCT (3D) analysis.Results: Direct stimulation with an alternating electric potential of 150 mV and 20 Hz for three times a day (45 min per unit) resulted in improved osseointegration of the triangular titanium implants in the tibiae of the rabbits. The ratio of bone area in histomorphometry (2D analysis) and bone volume (3D analysis) around the implant were significantly increased after stimulation compared to the untreated controls at sacrifice 84 days after implantation.Conclusion: The developed experimental design of an electrical stimulation system, which was directly located in the defect zone of rabbit tibiae, provided feedback regarding the integrity of the stimulation device throughout an experiment and would allow variations in the stimulation parameters in future studies. Within this study, electrical stimulation resulted in enhanced implant osseointegration. However, direct electrical stimulation of bone tissue requires the definition of dose-response curves and optimal duration of treatment, which should be the subject of subsequent studies.

Introduction: Titanium-based implants can be used to fill voids in bone reconstruction surgery. Through additive manufacturing (AM), it is possible to produce titanium implants with osteoconductive properties such as high porosity and low stiffness. AM facilitates a level of design flexibility and personalization that is not feasible with traditional techniques.Methods: In this study, osseointegration into titanium alloy (Ti-6Al-4V) lattices was investigated for 12 weeks post-implantation using a novel bicortical load-bearing ovine model. The objective was to assess the safety and efficacy of AM-fabricated implants using two lattice structures of contrasting stiffness spanning the full width of the femoral condyle.Results: This was achieved by evaluating implant osseointegration and bone–implant contact properties by histomorphometry, scoring local implant tissue responses via histopathology, and micro-computed tomography reconstruction.Discussion: We found that Ti-6Al-4V implants facilitated widespread and extensive osseointegration, with bone maturation ongoing at the conclusion of the trial period. Following the implantation period, no adverse clinical indications that could be directly ascribed to the presence of the implanted device were identified, as determined by macroscopic and microscopic observation.

Titanium (Ti) and its alloys are commonly used implant materials in orthopedics due to their good corrosion resistance, mechanical properties, and biocompatibility. However, the inherent biological inertness of the Ti surface leads to insufficient osseointegration and antibacterial ability, which may result in implant failure. Hydroxyapatite (HA) is currently the most widely used material in the biomedical field. It is one of the bioactive coating materials because of its chemical and structural similarity to natural bone. At present, many techniques are used to deposit HA as a coating material on Ti implants. The stability of the HA coating is the most important factor in determining the success of the implant. In addition, biofunctional ions have been introduced into HA coatings to enhance functional performance. This article aims to present the crystal structure and characteristics of HA and the principle of doping ions into HA. The preparation methods for the deposition of HA functional coatings on Ti and its alloys are introduced and discuss its advantages and limitations. In addition, the coating of doped HA on the surface of Ti and its alloys to improve their surface properties for bone integration is also reviewed.

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. 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. [Display omitted] [ABSTRACT FROM AUTHOR]

Objective: To compare efficiency and clinical efficacy of posterior single implant crowns (PSIC) fabricated using four digital workflows. Materials and Methods: Twenty‐two patients with one missing first molar were included. Each patient received four screw‐retained implant crowns fabricated through four different workflows including a fully digital workflow with immediate digital impression (Group i‐IOS), a fully digital workflow with digital impression after implant osseointegration (Group d‐IOS), a model‐based hybrid workflow using immediate analogue impression (Group i‐AI), and a model‐based hybrid workflow with conventional analogue impression after implant osseointegration (Group d‐AI). The crown delivery sequence was randomized and blinded. The efficiency for each workflow and clinical outcome of each crown were recorded. Results: The average clinical working time in fully digital workflows (i‐IOS 46.90 min, d‐IOS 45.66 min) was significantly lower than that in the hybrid workflows (i‐AI 54.59 min, d‐AI 55.96 min; p <.001). Significantly more laboratory time was spent in hybrid workflows (i‐AI 839.60 min, d‐AI 811.73 min) as compared to fully digital workflows (i‐IOS 606.25 min, d‐IOS 607.83 min, p <.01). No significant differences in the chairside time at delivery were found. More crowns in Group i‐AI (15%) needed additional laboratory interventions than in the other groups (p =.029). Conclusion: Digital impression and model‐free fully digital workflow improved prosthetic efficiency in the fabrication of PSIC. With the limitation that the results were only applicable to the implant system used and the digital technologies applied, findings suggested that workflows integrating immediate impression with implant surgery procedure was clinically applicable for restoration of PSIC. [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of biomimetic bone trabecular with the same porosity and pore size and regular porous structure on the adhesion, proliferation, and differentiation of osteoblasts, so as to provide theoretical basis for the improvement of osseointegration performance of titanium alloy implants. MethodsThe biomimetic bone trabecular and regular porous structures with the same porosity and pore size were generated by computer-aided software, and then processed into disc-shaped Ti6Al4V scaffolds with a diameter of 10 mm and a height of 3 mm by selective laser melting technology. MC3T3-E1 cells, the precursor cells of mouse osteoblasts in the logarithmic growth phase, were seeded on two kinds of scaffolds and divided into biomimetic bone trabecular group and regular porous structure group. After 3 hours of culture, acridine orange staining and phalloidin /DAPI staining were used to evaluate the number of cell adhesion. After 3 days of culture, the scaffolds were examined by scanning electron microscopy to evaluate the adhesion state of cells. After 1, 3, and 5 days of culture, the scaffolds were taken for CCK8 detection to observe the proliferation of cells. After 7 and 14 days of differentiation, alkaline phosphatase(ALP)activity was detected. After 14 days of differentiation, the expressions of osteogenesis-related genes(ALP, OCN, RUNX2)were detected by RT-PCR. After 30 days of differentiation, the scaffolds were stained with alizarin red and 100 g/L cetylpyridinium chloride was used to dissolve mineralized nodules. Calcium salt deposition was qualitatively and quantitatively detected to evaluate cell differentiation. Results The results of acridine orange and phalloidin /DAPI staining showed that the biomimetic trabecular Ti6Al4V scaffold adhered to more MC3T3-E1 cells than the regular porous structure, and the cytoskeleton of the former scaffold was more densely distributed. The results of scanning electron microscopy showed that the pseudopodia of MC3T3-E1 cells on the biomimetic bone trabecular Ti6Al4V scaffold were longer and the extension state was better than that of the regular porous structure. CCK8 test showed that the proliferation of MC3T3-E1 cells on the biomimetic trabecular bone titanium alloy scaffold was significantly higher than that on the regular porous structure on the 3rd and 5th day, and the difference gradually increased with the increase of time, with statistical significance(P<0.05). The results of cell differentiation test showed that ALP activity on the bionic trabecular scaffold was higher than that on the regular porous structure(P<0.05). The expressions of osteogenic genes(ALP, OCN, RUNX2)in MC3T3-E1 cells on the biomimetic bone trabecular titanium alloy scaffold were significantly higher than those on the regular porous structure(P<0.05). After 30 days of induction, the amount of calcium salt deposited in the bionic trabecular titanium alloy scaffold was significantly larger than that in the regular porous structure(P<0.05). Conclusion The biomimetic bone trabecular with a porosity of 65% and an equivalent pore size of 600 μm is more conducive to the adhesion, proliferation and differentiation of mouse osteoblast precursor cells MC3T3-E1 on the titanium alloy scaffold than the regular porous structure with the same porosity and pore size. It is theoretically more conducive to improving the osseointegration performance of titanium alloy implants. [ABSTRACT FROM AUTHOR]

Dental implant is an effective method in the treatment of missing teeth. The process of osseointegration of implant teeth involves the coordinated operation of immune system and bone system. The interaction between cells is closely related to bone formation and repair. Exosomes are important intercellular communication molecules. They were originally found in the supernatant of sheep erythrocytes cultured in vitro. They are micro vesicles with a diameter of 40~150 nm. They exist in a variety of cells and body fluids. They enter the target cells by endocytosis and transport, affecting the expression of cell genes and changing the fate of cells. It has an important regulatory function in the microenvironment of implant bone binding. It plays a role in bone remodeling through small molecular RNA, specific proteins and other growth factors secreted by different cells. This article reviews the role of bone derived cellderived exosomes in bone remodeling and their function in implant osseointegration. [ABSTRACT FROM AUTHOR]

In this manuscript, the authors propose a new technique for inserting implants immediately into the sockets corresponding to the lower first molars and, in any case, in the sockets in which the alveolar septum is still present. Immediate post-extraction implants are a widely discussed topic in the literature. Most authors currently consider the insertion of implants immediately after extraction less useful in terms of the procedure's questionable benefits in maintaining the height of the alveolar bone and more useful in terms of lessening patients' discomfort. Due to the anatomy of the post-extraction socket and its traditionally cylindrical geometry, this procedure is not always possible.: Next-generation REX-type blade implants were used via their insertion into the septum accompanied by a cortical lamina for periosteal inhibition without filling any of the alveoli.: In the 20 patients treated, the REX implant proved to be stable and surrounded by newly formed bone at the 18-month follow-up. This simple, easily employable technique allows an implant to be inserted immediately after extraction and in the same surgical session, with good patient compliance and good preservation of the alveolus due to the facilitation of periosteal inhibition. The excellent clinical results obtained with the use of a blade implant in the posterior sectors suggest that it is possible to reduce surgical sessions even in conditions of post-extraction sockets whose septum alone can ensure the primary stability essential for osseointegration. The use of a larger number of patients will also provide us with significant statistical results in support of this preliminary clinical work. New clinical studies are needed to understand the true potential of this method for application in daily clinical practice. [ABSTRACT FROM AUTHOR]

Background: osseointegration is a prerequisite for success of dental implants. Various biological and physical methods have been shown to enhance osseointegration. The aim of this study was to evaluate the effect of laser photobiomodulation on bone formation around dental implants. Material and Methods: Six adult male sheep served as the sample for this study. On either side of the lower border of mandible, four implants were inserted. To accommodate an implant that was 8 mm long and 4 mm wide, the implant bed was made to measure 10 mm long and 4.8 mm wide. Photobiomodulation with a 940-nm diode laser was applied daily for the next seven days, targeting the periimplant area. The animals were sacrificed at 4, 8, and 12 weeks (two animals at each time point). The dissected specimens were radiographed by micro-CT scan to evaluate the amount of bone formation. Results: At the three time points, the laser group should a statistically significant higher values of bone implant contact, bone volume, intersection surface, bone surface density trabecular number, and trabecular thickness (P<0.05). However, trabecular separation in the laser group was statistically significantly less than the control group (p<0.05). Conclusion: Laser therapy enhance bone-implant contact and increase osteointegration. A randomized clinical trial is recommended to reach a solid evidence-based conclusion. [ABSTRACT FROM AUTHOR]

The improvement of biodegradable metals is currently an active and promising research area for their capabilities in implant manufacturing. However, controlling their degradation rate once their surface is in contact with the physiological media is a challenge. Surface treatments are in the way of addressing the improvement of this control. Zinc is a biocompatible metal present in the human body as well as a metal widely used in coatings to prevent corrosion, due to its well-known metal protective action. These two outstanding characteristics make zinc coating worthy of consideration to improve the degradation behaviour of implants. Electrodeposition is one of the most practical and common technologies to create protective zinc coatings on metals. This article aims to review the effect of the different parameters involved in the electrochemical process on the topography and corrosion characteristics of the zinc coating. However, certainly, it also provides an actual and comprehensive description of the state-of-the-art of the use of electrodeposited zinc for biomedical applications, focusing on their capacity to protect against bacterial colonization and to allow cell adhesion and proliferation. [ABSTRACT FROM AUTHOR]

Abstract Background The biomaterial integration depends on its interaction with the host immune system. Monocyte-macrophage lineage cells are immediately recruited to the implant site, polarized into different phenotypes, and fused into multinucleated cells, thus playing roles in tissue regeneration. IL-1R-associated kinase 4 (IRAK4) inhibition was reported to antagonize inflammatory osteolysis and regulate osteoclasts and foreign body giant cells (FBGCs), which may be a potential target in implant osseointegration. Methods In in-vitro experiments, we established simulated physiological and inflammatory circumstances in which bone-marrow-derived macrophages were cultured on sand-blasted and acid-etched (SLA) titanium surfaces to evaluate the induced macrophage polarization, multinucleated cells formation, and biological behaviors in the presence or absence of IRAK4i. Then, bone marrow stromal stem cells (BMSCs) were cultured in the conditioned media collected from the aforementioned induced osteoclasts or FBGCs cultures to clarify the indirect coupling effect of multinucleated cells on BMSCs. We further established a rat implantation model, which integrates IRAK4i treatment with implant placement, to verify the positive effect of IRAK4 inhibition on the macrophage polarization, osteoclast differentiation, and ultimately the early peri-implant osseointegration in vivo. Results Under inflammatory conditions, by transforming the monocyte-macrophage lineage cells from M1 to M2, IRAK4i treatment could down-regulate the formation and activity of osteoclast and relieve the inhibition of FBGC generation, thus promoting osteogenic differentiation in BMSCs and improve the osseointegration. Conclusion This study may improve our understanding of the function of multinucleated cells and offer IRAK4i as a therapeutic strategy to improve early implant osseointegration and help to eliminate the initial implant failure.

Osseointegration seems to be a foreign body reaction equilibrium due to the complicated interactions between the immune and skeletal systems. The heterogeneity of the osteoimmune microenvironment in the osseointegration of implant materials remains elusive. Here, a single-cell study involving 40043 cells is conducted, and a total of 10 distinct cell clusters are identified from five different groups. A preliminary description of the osteoimmune microenvironment revealed the diverse cellular heterogeneity and dynamic changes modulated by implant properties. The increased immature neutrophils, Ly6C + CCR2hi monocytes, and S100a8hi macrophages induce an aggressive inflammatory response and eventually lead to the formation of fibrous capsule around the stainless steel implant. The enrichment of mature neutrophils, FcgR1hi and differentiated immunomodulatory macrophages around the titanium implant indicates favorable osseointegration under moderate immune response. Neutrophil-depletion mice are conducted to explore the role of neutrophils in osseointegration. Neutrophils may improve bone formation by enhancing the recruitment of BMSCs via the CXCL12/CXCR3 signal axis. These findings contribute to a better knowledge of osteoimmunology and are valuable for the design and modification of ‘osteoimmune-smart’ biomaterials in the bone regeneration field.

Posterior mandibular edentations with a reduced alveolar ridge require a complex treatment plan. Treatment concepts involving two to four implants supporting an overdenture have been proposed. In this article, we present a clinical case of implanto-prosthetic rehabilitation of the posterior mandibular area with bone addition using the synthetic biomaterial “Kolapol KP – 3LM”.

Background: Peri-implantitis additional treatment generally aims to repair damaged tissue through a regenerative approach. Human umbilical cord mesenchymal stem cells (hUCMSCs) produce a high osteogenic effect and are capable of modulating the immune system by suppressing inflammatory response, modulating bone resorption, and inducing endogenous osteogenesis. Aim: This study was intended to discover the effect of hUCMSCs on an implant osseointegration process in peri-implantitis rat subjects as assessed by several markers including interleukin-10 (IL-10), transforming growth factor-β (TGF-β), receptor activator of nuclear factor kappa- β ligand (RANKL), bone morphogenic protein (BMP-2), osterix (Osx), and osteoprotegerin (OPG). Material and methods: The research design implemented during this study represented a true experimental design incorporating the use of Rattus norvegicus (Wistar strain) as subjects. Results: Data analysed by means of a Brown Forsythe test indicated differences between the increase in BMP-2 expression (p

Metallodrugs have a potent application in various medical fields. In the current study, we used a novel Palladium(II) thiazolinyl picolinamide complex that was directly fabricated over the titanium implant to examine its potency in inhibiting dual-species biofilms and exopolysaccharides. Additionally, inhibition of mono- and dual-species biofilms by coated titanium plates in an in vitro joint microcosm was performed. The study was carried out for 7 days by cultivating mono- and dual-species biofilms on titanium plates placed in both growth media and artificial synovial fluid (ASF). By qPCR analysis, the interaction of co-cultured biofilms in ASF and the alteration in gene expression of co-cultured biofilms were studied. Remarkable alleviation of biofilm accumulation and EPS secretion was observed on the coated titanium plates. The effective impairment of biofilms and EPS matrix of biofilms on Pd(II)-E-coated titanium plates were visualized by Scanning Electron Microscopy. Moreover, coated titanium plates improved the adhesion of osteoblast cells, which is crucial for a bone biomaterial. The potential bioactivity of coated plates was also confirmed at the molecular level using qPCR analysis. The stability of coated plates in ASF for 7 days was examined with FESEM-EDAX analysis. Collectively, the present study provided an excellent anti-infective effect on Pd(II)-E-coated titanium plates without affecting their biocompatibility with bone cells. [ABSTRACT FROM AUTHOR]

Functional tooth replacement and bone regeneration are areas of interest in modern dentistry and dental implant research involves increased attention to osteointegration. The aim of the study was to develop a small, inexpensive and reproducible animal model for testing dental implants. Fifteen male Wistar rats, 20 weeks old, average weight of 400 grams were included in the study. They were subjected to a rigorous bone support preparation protocol so that the maxillary first premolar was extracted from the left half arch. After a period of 30 days, necessary for the bone refilling of the dental alveolus, the radiological examination was performed. Then a surgical intervention was performed to mount the titanium implants of an adapted size. Clinically, the evolution was favorable, with no signs of discomfort or oral infection. At the radiological evaluation, optimal bone regeneration could be observed. necessary to ensure a suitable place for implant mounting. The implantation procedure was laborious due to the limited working area. However, rats are proving to be suitable animal models for implant-related studies or innovative treatments administered under pathological conditions. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to review the literature on current surface modification strategies used to improve the binding efficiency of an emerging biological material, polyetheretherketone (PEEK), with bone and soft tissues. Study selection: This review was based on articles retrieved from PubMed, Google Scholar, Web of Science, and ScienceDirect databases. The main keywords used during the search were "polyetheretherketone (PEEK)," "implant," "surface modification," "biomaterials," "bone," "osseointegration," and "soft tissue.". Results: The suitability of PEEK surface modification strategies has been critically analyzed and summarized here. Many cell and in vivo experiments in small animals have shown that the use of advanced modification technologies with appropriate surface modification strategies can effectively improve the surface inertness of PEEK, thereby improving its binding efficiency with bone and soft tissues. Conclusions: Surface modifications of PEEK have revealed new possibilities for implant treatment; however, most results are based on in vitro or short-term in vivo evaluations in small animals. To achieve a broad application of PEEK in the field of oral implantology, more in vivo experiments and long-term clinical evaluations are needed to investigate the effects of various surface modifications on the tissue integration ability of PEEK to develop an ideal implant material. [ABSTRACT FROM AUTHOR]

Aim: To evaluate and compare the crestal bone loss and implant stability with and without hyaluronic acid gel delivery at osteotomy site. Materials and Methods: This is a Prospective randomized controlled clinical trial. Eleven patients with 30 edentulous sites were randomly divided into two groups. Test (15 sites with hyaluronic acid gel injection) and Control (15 sites without hyaluronic acid gel injection). Peri-implant crestal bone loss around the implant and stability were measured at baseline and three months. Statistical analysis was done using Mann-Whitney U test and Wilcoxson Signed-Rank test. Results: Primary stability scores for the test and control groups were 70.45 ± 1.49 and 69.53 ± 1.69, respectively and was not statistically significant. Secondary stability scores for the test and control group were 72.37 ± 1.42and 70.63 ± 1.61 respectively and was statistically significant, mean crestal bone loss for the test and control groups was 0.83 ± 0.31 and 1.27 ± 0.32, respectively. which was statistically significant (p-value < 0.05). Conclusion: Within the study's limitations, the results showed that the local injection of osteotomy sites with hyaluronic acid showed a significant increase in stability and reduction in crestal bone loss. [ABSTRACT FROM AUTHOR]

Purpose: Good cell adhesion is an important prerequisite for soft tissue attachment on implant abutment or crown surfaces. The aim of this study was to evaluate the adhesion and proliferation of human epithelial cells on sol-gel--derived TiO2-coated and noncoated zirconia. Materials and Methods: Altogether, 56 zirconia disks (Z-CAD, Metoxit) were fabricated for this study. Half of the disks were coated with a sol-gel--derived TiO2 coating (MetAlive, ID Creations). The rest of the disks were noncoated and formed the control group. Surface properties of the disks were characterized by contact angle measurements and surface free energy (SFE) calculation. The cell adhesion was tested by cultivating epithelial cells (20,000 cells/cm²) on the experimental disks for 1, 3, 6, and 24 hours, after which the fluorescence of the samples was measured (BioTek synergy HT). The amount of cells was detected by comparing the fluorescence value to the standard curve. In addition, the proliferation was studied by growing epithelial cells (25,000 cells/cm²) for 1, 3, and 7 days. The number of cells was calculated by defining the absorbance of the samples (Multiskan EX, Thermo Labsystems), followed by a comparison with the standard curve. Finally, the samples were processed for light microscopy. Results: TiO2-coated disks were significantly more hydrophilic with higher total SFE than noncoated disks (P < .05). The amount of epithelial cells was greater on TiO2-coated disks than on controls after 24 hours (P < .05). Regarding cell proliferation, the difference was statistically significant (P < .05) on days 3 and 7. Light microscope evaluation confirmed viable cells, which were in immediate close contact with both substrate surfaces. The cell layers on the coated disks appeared to be more uniform and cell rich than the layers on noncoated disks. Conclusion: This study indicated that TiO2 coating improves epithelial cell attachment and proliferation on zirconia surfaces. This has good potential to enhance formation of the epithelial junction to the coated zirconia surfaces. [ABSTRACT FROM AUTHOR]

This case report describes removal of anterior bridge, followed by immediate placement of a dental implant in the prepared socket and temporization by a bonded restoration. The socket was prepared to the required depth and two NobleBiocare Implants were inserted followed by temporization by a bonded restoration. An impression was made 3 months after implant insertion, and a definitive restoration was placed. The atraumatic operating technique and the immediate insertion of the Implant resulted in the preservation of the hard and soft tissues at the extraction site. The dental implant and provisional restoration provided the patient with immediate aesthetics, function, comfort, and most importantly preservation of tissues. [ABSTRACT FROM AUTHOR]

Background: The biomaterial integration depends on its interaction with the host immune system. Monocyte-macrophage lineage cells are immediately recruited to the implant site, polarized into different phenotypes, and fused into multinucleated cells, thus playing roles in tissue regeneration. IL-1R-associated kinase 4 (IRAK4) inhibition was reported to antagonize inflammatory osteolysis and regulate osteoclasts and foreign body giant cells (FBGCs), which may be a potential target in implant osseointegration. Methods: In in-vitro experiments, we established simulated physiological and inflammatory circumstances in which bone-marrow-derived macrophages were cultured on sand-blasted and acid-etched (SLA) titanium surfaces to evaluate the induced macrophage polarization, multinucleated cells formation, and biological behaviors in the presence or absence of IRAK4i. Then, bone marrow stromal stem cells (BMSCs) were cultured in the conditioned media collected from the aforementioned induced osteoclasts or FBGCs cultures to clarify the indirect coupling effect of multinucleated cells on BMSCs. We further established a rat implantation model, which integrates IRAK4i treatment with implant placement, to verify the positive effect of IRAK4 inhibition on the macrophage polarization, osteoclast differentiation, and ultimately the early peri-implant osseointegration in vivo. Results: Under inflammatory conditions, by transforming the monocyte-macrophage lineage cells from M1 to M2, IRAK4i treatment could down-regulate the formation and activity of osteoclast and relieve the inhibition of FBGC generation, thus promoting osteogenic differentiation in BMSCs and improve the osseointegration. Conclusion: This study may improve our understanding of the function of multinucleated cells and offer IRAK4i as a therapeutic strategy to improve early implant osseointegration and help to eliminate the initial implant failure. [ABSTRACT FROM AUTHOR]

BACKGROUND: Preliminary studies have shown that micro-grooved patterns of porous hydroxyapatite have good osteoinductivity, biocompatibility, and osteoconductivity, which provides a new idea for clinical repair of jaw defects and expansion of implantation. OBJECTIVE: To observe the osseointegration of the micro-grooved patterns of porous hydroxyapatite with the dental implant after repairing large-area defect of the canine mandible. METHODS: Micro-grooved patterns of porous hydroxyapatite were made. Eight beagle dogs were randomly divided into experimental group and control group (n=4 per group). Bilateral mandibular premolars of the dogs were extracted. Three months later, two cylindrical bone defects of 8 mm×10 mm were fabricated. The experimental group was implanted with micro-grooved patterns of porous hydroxyapatite and the control group was implanted with autologous bone. Three months later, a 4 mm × 10 mm Dentium implant was implanted in the bone defect repair area. Samples were taken at 4 and 12 weeks after implantation. Cone beam CT examination, Micro-CT scan, histological examination, and implant resonance frequency analysis were performed. RESULTS AND CONCLUSION: (1) Cone beam CT showed that there were some low-density shadows at the implant-osseointegration interface between the experimental group and the control group 4 weeks after the operation. At 12 weeks after the operation, the area of the implant-osseointegration surface increased in the experimental group and the control group. The implant was closely combined with the implant material, and there was no obvious shadow. (2) Micro-CT data analysis showed that the amount of bone covered on the implant surface in the experimental group was less than that in the control group 4 weeks after operation (P < 0.05). There was no significant difference in the amount of bone covered on the implant surface between the two groups at 12 weeks (P > 0.05). (3) Histological morphology: Hematoxylin-eosin, Masson and methylene blue-acid fuchsin staining showed that new bone formation was seen in both groups at 4 weeks. The bone contact rate in the experimental group was less than that in the control group (P < 0.05). At 12 weeks, the amount of bone around the implants in the two groups increased significantly. There was no significant difference in bone contact rate between the two groups (P > 0.05). (4) The resonance frequency analysis of the implants showed that the implant stability quotient of the experimental group was lower than that of the control group at 4 and 12 weeks after implantation (P < 0.05), but the implants of the two groups were stable in each period. (5) It is concluded that micro-grooved patterns of porous hydroxyapatite can repair large-area defects of canine jaws and induce the new bone formation, showing perfect osseointegration with implants. [ABSTRACT FROM AUTHOR]

Prosthesis implantation and bone integration under bacterial infection are arduous challenges in clinical practice. It is well known that the reactive oxygen species (ROS) produced by bacterial infection around the bone defects will further hinder bone healing. To solve this problem, we prepared a ROS-scavenging hydrogel by cross-linking polyvinyl alcohol and a ROS-responsive linker, N1-(4-boronobenzyl)-N3-(4-boronophenyl)-N1, N1, N3, N3-tetramethylpropane-1, 3-diaminium, to modify the microporous titanium alloy implant. The prepared hydrogel was used as an advanced ROS-scavenging tool to promote bone healing by inhibiting the ROS levels around the implant. Bifunctional hydrogel serving as a drug delivery system can release therapeutic molecules, including vancomycin, to kill bacteria and bone morphogenetic protein-2 to induce bone regeneration and integration. This multifunctional implant system that combines mechanical support and disease microenvironment targeting provides a novel strategy for bone regeneration and integration of implants in infected bone defects. [ABSTRACT FROM AUTHOR]

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Background. Infection of percutaneous implants in patients with limb amputation is the most common complication. This study aimed to evaluate the microbiological contamination of the implantation zone depending on the implant mechanical compression under the conditions of the additional external fixation. Methods. The study was performed on 36 male rabbits. The tibia of all the rabbits was sawn at the border of the upper and middle parts. The medullary canal was reamed and a percutaneous implant was placed in the tibial stump. The segment and the implant were fixed with an Ilizarov apparatus. An additional compression device was installed in 30 animals. We used 5 compression modes, accordingly, 6 experimental groups were formed, 6 animals in each: group 1 without compression, group 2 compression on the implant with force of 0.053 N/mm2, group 3 compression on the implant with force of 0.105 N/mm2, group 4 compression on the implant with force of 0.158 N/mm2, group 5 compression on the implant with force of 0.211 N/mm2, group 6 compression on the implant with force of 0.263 N/mm2. The restraint was removed 6 weeks after implantation for a total follow-up of 26 weeks. The microflora of the place where the implant enters the skin (the implant / skin interface) was investigated, the level of blood leukocytes and the level of C-reactive protein in blood serum were determined. Results. On days 9-10 after implantation, significant differences in the microbial landscape were found at the site of the exit of the metal implant in animals of different groups. The largest number of strains was found in animals of groups 1, 5 and 6, the smallest in groups 2 and 3. The most frequently detected strains: S. saprophyticus and Enterococcus spp. It was found that the greatest statistically significant increase in the level of CRP in the blood serum was observed in animals of group 6. The level of leukocytes in animals of all groups did not change statistically significantly relative to preoperative values. Animals with better osseointegration (groups 2 and 3 no cases of implant loss) showed a minimal number of growing strains. Conclusions. The microbiological profile of the implantation zone of percutaneous implants changes depending on the amount of mechanical compression. The optimal mode is 0.053-0.105 N/mm2.

Purpose: The possibility that the sympathetic nervous system (SNS) controls bone remodeling has been raised; however, the actual function of the SNS in osseointegration is still unknown. This study aimed to investigate the effect of chemical sympathectomy on peri-implant osseointegration in adult mice. Materials and Methods: Forty C57BL/6J mice (8-week-old) were divided into two groups: a sympathectomy group and a control group, which were administered 6-hydroxydopamine and saline, respectively, by intraperitoneal injection for 5 days. Then, the mice were exposed to implant surgery. Analyses of serum chemistry, microcomputed tomography, biomechanical test, and bone histomorphometry were employed at 2 and 4 weeks. Results: Compared with the control, the chemical sympathectomy group had a higher serum level of C-terminal collagen I cross-links but lower serum osteocalcin. After 4 weeks, peri-implant trabecular microstructure, including trabecular volume, trabecular thickness, the percentage of osseointegration, and bone-to-implant contact, was lower; however, the trabecular separation was higher in the sympathectomy group mice in comparison with the control group. In addition, the strength of bone-titanium integration measured by the biomechanical resistance test was lower. Furthermore, histomorphologic evidence revealed that the osteoclast counts were higher in the sympathectomy group, while the mineral apposition rate and the bone formation rate per bone surface were significantly lower. Conclusion: Within the limitations of this experimental study, the data showed that chemical sympathectomy has a negative effect in peri-implant osseointegration, suggesting that the SNS may need to be taken into consideration in terms of peri-implant bone healing. [ABSTRACT FROM AUTHOR]

Guided bone regeneration (GBR) is a well-documented and widely-used dental surgical procedure for the treatment of various types of alveolar bone defects. The aim of the study was to evaluate the long-term effectiveness of the GBR procedure in correcting small peri-implant bone dehiscence using the xenogeneic deproteinized bovine bone mineral material and a xenogeneic native bilayer collagen membrane. The present study was designed as a retrospective study. Seventy-five bone-level tapered two-piece dental implants Conelog®, Camlog (Biotechnologies AG, Switzerland) were divided into two groups G1—no bone augmentation (no GBR)—44 implants and G2—bone augmentation (GBR)—31 implants. For both groups, the closed healing protocol with a primary wound closure was used. The incidence of peri-implantits was evaluated, the quantitative assessment of soft tissue thickness was performed using the ultrasound (USG) device, quantitative assessment of marginal bone loss (MBL) was done. The prevalence of peri-implantitis was 5.3%, with a three-fold increase in peri-implantitis comparing the groups without and with bone augmentation (G1 = 2.27%, G2 = 9.7%). The average keratinized gingiva thickness was 1.87 mm and did not differ significantly between groups. No statistically significant differences in MBL between G1 and G2 were found. When dividing patients by gender, no statistically significant differences were observed. When dividing patients by age groups, statistically significant differences were observed between the youngest and oldest groups of patients. Within the limitations of this study, it can be concluded that the use of xenogeneic bone and a xenogeneic collagen membrane in a GBR procedure can be recommended to correct small peri-implant bone dehiscence. [ABSTRACT FROM AUTHOR]

When creating titanium-containing bone implants, the bioactive coatings that promote their rapid engraftment are important. The engraftment rate of titanium implants with bone tissue depends significantly on the modification of the implant surface. It is achieved by changing either the relief or the chemical composition of the surface layer, as well as a combination of these two factors. In this work, we studied the creation of composite coatings with a two-level (the micro- and nanolevel) hierarchy of the surface relief, which have bioactive and bactericidal properties, which are promising for bone implantation. Using the developed non-lithographic template electrochemical synthesis, a composite coating on titanium with a controlled surface structure was created based on an island-type TiO2 film, silver and hydroxyapatite (HAp). This TiO2/Ag/HAp composite coating has a developed surface relief at the micro- and nanolevels and has a significant cytological response and the ability to accelerate osteosynthesis, and also has an antibacterial effect. Thus, the developed biomaterial is suitable for production of dental and orthopedic implants with improved biomedical properties. [ABSTRACT FROM AUTHOR]

Peri -implantitis additional treatment generally aims to repair damaged tissue through a regenerative approach. Human umbilical cord mesenchymal stem cells (hUCMSCs) produce a high osteogenic effect and are capable of modulating the immune system by suppressing inflammatory response, modulating bone resorption, and inducing endogenous osteogenesis. Aim: This study was intended to discover the effect of hUCMSCs on an implant osseointegration process in peri -implantitis rat subjects as assessed by several markers including interleukin-10 (IL-10), transforming growth factor-β (TGF-β), receptor activator of nuclear factor kappa- β ligand (RANKL), bone morphogenic protein (BMP-2), osterix (Osx), and osteoprotegerin (OPG). Material and methods: The research design implemented during this study represented a true experimental design incorporating the use of Rattus norvegicus (Wistar strain) as subjects. Results: Data analysed by means of a Brown Forsythe test indicated differences between the increase in BMP-2 expression (p < 0.000) and Osx expression (p < 0.001) and between RANKL expression (p < 0.001, Tukey HSD) and OPG expression (p < 0.000, Games Howell). Conclusion: According to the findings of this research, hUCMSCs induction is successful in accelerating and enhancing osteogenic activity and implant osseointegration in peri -implantitis rat subjects. [ABSTRACT FROM AUTHOR]

Introduction: Early development of infection in periimplant tissues is often a cause of implant failure, as clinically assessed by checking bleeding on probing, redness, swelling and presence of pain. Radiographically, bone loss can be seen early in such cases. This can occur due to several possible host-related factors, such as periodontal disease or surgery related to a poor sterilisation protocol. Aim: To assess the peri-implant health among the implants placed in a private dental hospital in Chennai, India. Materials and methods. A retrospective cross-sectional study was conducted using 712 samples from the Department of Implantology after reviewing and analysing the data of 86,000 patients between June 2019 and March 2021. Microsoft Excel® was used to tabulate the collected data. The variables assessed were age, gender, presence of infection and site of implant placement. Chi square analysis was done with the level of significance set at p<0.05. Appropriate graphs, tables and charts were constructed using SPSS for a clear representation of the results obtained. Results and discussion: The sample had a gender distribution of 57.81% males and 42.19% females, 16.97% among 20-30-year-olds, 22.9% in 31-40-years-olds, 23.72% in 41-50-year-olds, 22.62% in 51-60-year-olds and 13.79% in 61+ year-olds. The most (27.29%) common site of implant placement was sextant 4, specifically in relation to the first molar. 99.58% of implant sites showed no signs of infection, and 0.43% of them showed poor peri-implant health post recovery period. Conclusions: Within the limits of the study, it can be concluded that post recovery peri implant health was good in 99.58% of implant sites, poor values being noticed in only 0.43% of implant cases. [ABSTRACT FROM AUTHOR]

Explantation of fully or partially osseointegrated titanium implants is a complex procedure for myriad reasons and often results in major bone loss and pronounced defects of the hard and soft tissues. This may require more elaborate surgical interventions in cases of re-implantation. In this patient case, an osseointegrated titanium implant with some visible bone loss, missing attached mucosa at the buccal aspect, and a nonideal three-dimensional (3D) position had to be explanted. For this, the implant’s inner connection was heated using a CO2 laser, which resulted in localized laser-induced thermo-necrosis at the bone-to-implant contact. One week following laser application, explantation could be performed easily with a torque slightly more than 35 Ncm. No complications occurred during the healing period. The result was a very easily performed explantation while preserving a maximum of the surrounding bony structure. Healing was uneventful, and no further visible bone loss could be observed during the healing time. [ABSTRACT FROM AUTHOR]