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Background: Bioactive surface modifications have been proposed to enhance osseointegration and longevity of dental implants. This study aimed to systematically review and perform a meta-analysis on the effectiveness of various bioactive coatings in promoting bone integration and improving implant longevity. Methods: A systematic review was conducted, including studies that investigated bioactive surface modifications on titanium dental implants. Outcomes of interest were bone-to-implant contact (BIC) and implant longevity over a 30-day period. Data were extracted and analyzed using RevMan 5 (version 5.4.1), with forest plots generated to represent the mean difference (MD) and 95% confidence intervals (CI) under a random effects model. Results: The meta-analysis showed a significant improvement in BIC for surface-modified implants, with an overall MD of 7.29 (95% CI [2.94, 11.65]). Heterogeneity analysis indicated moderate heterogeneity (Tau² = 18.57, Chi² = 16.08, df = 8, P = 0.04, I² = 50%). The test for overall effect yielded Z = 3.28 (P = 0.001). For implant longevity, the overall MD was 7.52 (95% CI [3.18, 11.85]), with moderate heterogeneity (Tau² = 17.28, Chi² = 14.95, df = 8, P = 0.06, I² = 47%). The test for overall effect yielded Z = 3.40 (P = 0.0007). Conclusion: Bioactive surface changes significantly improved osseointegration and lifespan of dental implants. Collagen-based coatings consistently encouraged early bone integration, while BMP-2 combinations were effective for osseointegration. Optimizing bioactive agent doses and combinations was critical for achieving desired outcomes. [ABSTRACT FROM AUTHOR]

Purpose: Diminished bone levels or the lack of osseointegration can lead to higher rates of failure of dental implants. The present study is aimed to evaluate the correlation between hypertension, diabetes mellitus and hyperlipidemia, on the marginal bone loss (MBL) surrounding dental implants among patients attending the University of Nevada, Las Vegas dental clinics. Methods: Clinical notes from patients at the University of Nevada, Las Vegas (UNLV) dental clinics were analyzed using AxiUm™ software. The study included patients with dental implants diagnosed with hypertension, diabetes mellitus, and hyperlipidemia who attended the UNLV School of Dental Medicine clinics from 2012 to 2022. Exclusions were made for patients with acquired immune deficiency syndrome and those with a limited number of radiographs. A search was conducted using keywords such as 'systemic disease,' 'marginal bone loss,' 'dental implant,' 'high cholesterol,' 'hypertension,' and 'diabetes' within the system. Results: Out of 1,310 potentially eligible patients, 57 fulfilled the inclusion criteria. The total number of evaluated implants was 165. 18% of the sample patients were 55 to 64 years of age, and 79% were 65 or above. 45.6% of patients reported having more than four systemic diseases and 67% of patients had four or more prescription medications. Patients diagnosed with hypertension (78.95%) or hyperlipidemia (73.68%) had the highest presence of marginal bone loss surrounding the dental implant(s) while those with diabetes (40.35%) had the least amount of MBL. Patients diagnosed with both hypertension and hyperlipidemia (29.82%) experienced the highest incidence of MBL around implants. The medications prescribed to combat these health issues, such as statins and antihypertensive, also showed the same trends and corresponded with a higher prevalence of MBL. Conclusions: Within the limitations of the present investigation, patients diagnosed with hyperlipidemia and hypertension were more likely to exhibit MBL surrounding dental implants. [ABSTRACT FROM AUTHOR]

Purpose: Gap non-union of long bones are challenging problems in orthopaedic patients. Non-vascularized fibular grafting is a simple, cost effective, single stage procedure and is an accepted method of reconstruction for gap non unions in children. However, there is a risk of non-union when a long avascular strut of fibula is used. The periosteum, by itself has high biological activity and is helpful in osteointegration. Harvesting the fibula with the periosteum gives the advantage of mechanical and biological support in a gap non-union. Methods: During 2020 to 2022, 13 patients presented to us with gap nonunion of long bones due to various aetiology. The mean age of the patients was six years with a mean bone gap of 4.2 cm. A modified technique of harvesting the fibula with the periosteum is described. The graft was stabilized with the recipient bone by intra medullary or extra medullary implants. Results: Union occurred in average 12.7 weeks in all except one patient with congenital pseudoarthrosis of tibia. The fibula on the harvest site regenerated completely in all other patients. One patient had a superficial infection. Children were followed were an average of 17.5 months and there was no incidence of graft resorption or fracture. Osteoperiosteal fibula graft is a simple, effective and cost-effective procedure for the treatment of gap non-unions in children. It offers the advantage of both biological and mechanical support, with high union rates and low complication rates. [ABSTRACT FROM AUTHOR]

Introduction: Bone anchored hearing implants (BAHI) are considered for conductive and mixed hearing loss, relying on osseointegration of a titanium implant. Limitations relate to constant skin contact, with resultant percutaneous infections and granulation. This study investigates whether patient characteristics and implant-specifications contribute to BAHIs' skin complications in a cohort with a uniform surgical approach. Methods: A 10 year (2014–2024) retrospective cohort study was conducted on BAHI procedures that were undertaken using a tissue-preserving 'punch' technique. Data on patient demographics, co-morbidities, implant type, surgical approach, and complications were collected. Poisson regression analysis was used to identify predictors of complications. Results: A total of 53 patients undergoing 55 BAHI surgeries by three ENT consultants were included. Factors that greatly increased implant-related percutaneous infections included the Cochlear™ BIA400 implant when compared to the Ponto™ BHX implant (twofold, CI 2.03–2.16), abutment sizes ≤ 10 mm (fourfold, CI 3.99–4.12) and male gender (9%, CI 1.07–1.12). Granulation episodes were affected by cardiovascular disease (CVD) status (1.5-fold, CI 0.26–0.78), BIA400 implant (threefold, CI 8.8.–9.2) and abutment sizes ≤ 10 mm (fourfold, CI 3.6–3.73). Revision surgery episodes increased with diabetic status (1.2-fold, CI 0.06–0.37) and abutment sizes ≤ 10 mm (threefold, 3.303–3.304). Conclusions: Larger cohort studies are required to confirm findings, particularly for implant and abutment size contributions. However, the findings suggest that using a larger abutment size when skin thickness meassuremets are borderline, improved hygiene education in male patients, pre-operative optimisation of CVD and diabetes, and adjusted patient follow-up based on risk stratification of the contributing factors to complication rates could reduce complication rates. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA) has been widely used for coating metal bone implants. However, HA coating may separate from the metal substrates, resulting in poor performance such as inflammatory reactions which may finally lead to implant failure. Dispersing HA into metal substrate may be a viable solution but such a composite may suffer from inferior mechanical strength. Therefore, a functionally graded material (FGM) with HA dispersing in metal substrate in gradients is introduced to increase surface osteogenic capability and simultaneously maintain a good mechanical strength of the bone implant. In this study, Ti6Al4V(Ti64)-HA composite with different component of HA and their corresponding FGMs were fabricated by selective laser melting (SLM). It was demonstrated that compared with the pure Ti64 and Ti64-2.5%HA composite, Ti64-1%HA composite seemed to have a better osteogenic promoting property in vitro. Both the FGMs significantly promoted the osteogenic activities of the pure Ti64 in vivo. Moreover, functionally graded structure improved the anti-compression properties of composites. [ABSTRACT FROM AUTHOR]

Currently, various artificial implants have been devised and applied to the human body. Traditionally, Traditionally, titanium and its alloys are the most well-known implant materials due to their excellent mechanical properties and processability. The biocompatibility of titanium-based implants is also commendable, attributed to the inherent biological inertia of the oxidation layer spontaneously formed on their surface. Additionally, zirconia, a type of biological, has garnered increasing attracted because of its superior mechanical properties and enhanced biocompatibility compared to titanium. Promoting bone healing and integration between host bone and implants remains a significant issue. Rapid and stable osseointegration at the bone-implant interface is essential for the successful integration of orthopedic implants. This review compares the osseointegration properties of titanium-based and zirconia implants and summarizes the factors that affect osseointegration. Furthermore, it proposes outlooks for improving osseointegration. [ABSTRACT FROM AUTHOR]

The current primary treatment approach for malignant pelvic tumors involves hemipelvic prosthesis reconstruction following tumor resection. In cases of Enneking type II + III pelvic tumors, the prosthesis necessitates fixation to the remaining iliac bone. Prevailing methods for prosthesis fixation include the saddle prosthesis, ice cream prosthesis, modular hemipelvic prosthesis, and personalized prosthetics using three-dimensional printing. To prevent failure of hemipelvic arthroplasty protheses, a novel fixation method was designed and finite element analysis was conducted. In clinical cases, the third and fourth sacral screws broke, a phenomenon also observed in the results of finite element analysis. Based on the original surgical model, designs were created for auxiliary dorsal iliac, auxiliary iliac bottom, auxiliary sacral screw, and auxiliary pubic ramus fixation. A nonlinear quasi-static finite element analysis was then performed under the maximum load of the gait cycle, and the results indicated that assisted sacral dorsal fixation significantly reduces stress on the sacral screws and relative micromotion exceeding 28 μm. The fixation of the pubic ramus further increased the initial stability of the prosthesis and its interface osseointegration ability. Therefore, for hemipelvic prostheses, incorporating pubic ramus support and iliac back fixation is advisable, as it provides new options for the application of hemipelvic tumor prostheses. [ABSTRACT FROM AUTHOR]

Purpose: The present study evaluated osteopenia (OPN) and osteoporosis (OP) as risk factors for dental implant failure and repeat failure. Methods: We performed a retrospective study on over 100 randomly selected patients per analysis to determine the effect of health status, smoking status, sex, implant location and operative conditions on first and second (re-implantation) implant survival. Analyses were conducted first using chi-squared test, followed by multiple logistic regression for significant variables. Results: In the cohort examining the effect of myriad risk factors on second implant survival, it was found that OPN and OP greatly impacted implant survival, wherein patients with osteoporosis or osteopenia had significantly more implant failures (p = 0.0353). Sex and operative conditions had no effect on implant survival, while implant location showed a notable effect wherein significantly more failures occurred in the maxilla vs mandible (p = 0.0299). Upon finding that OPN and OP have a significant effect on second implant survival, we conducted an additional study focusing on the impact of health status. Based on the multiple logistical regression analysis, we found that OPN and OP are the most significant factor in first implant survival (p = 0.0065), followed by diabetes (p = 0.0297). Importantly, it was observed that early implant failure is also significantly correlated with osteoporosis (p = 0.0044). Conclusion: We show here a marked relationship in which the risk of first and second implant failure are significantly higher in patients with osteoporosis and osteopenia. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to compare micromotion of two new cementless tibial baseplates to a cementless design with well‐published clinical success. Methods: Three cementless tibial baseplate designs (fixed‐bearing [FB] with keel and cruciform pegs, rotating‐platform with porous central cone and pegs, FB with cruciform keel and scalloped pegs) were evaluated on sawbone models. Loading was applied to the baseplate at a rate of 1 Hz for 10,000 cycles, which represents 6–8 weeks of stair descent. This time frame also represents the approximate time length for the induction of biologic fixation of cementless implants. Compressive and shear micromotion at the sawbone–implant interface were measured. Results: At the end of the loading protocol, the central cone rotating‐platform design exhibited greater micromotion at the anterior (p < 0.001), posterior (p < 0.001) and medial locations (p = 0.049) compared to the other two implants. The central cone design also exhibited greater translational micromotion in the sagittal plane at the medial (p = 0.001) and lateral locations (p = 0.034) and in the coronal plane anteriorly (p = 0.007). Conclusion: The cementless central cone rotating‐platform baseplate demonstrated greater vertical and translational micromotion compared to the two FB baseplates with a keel underloading. This may indicate lower initial mechanical stability in implants without a keel, which possibly affects osseointegration. The implication of this is yet unknown and requires further long‐term clinical follow‐up to correlate these laboratory findings. Level of Evidence: V (biomechanical study). [ABSTRACT FROM AUTHOR]

Published data have substantiated the use of osseointegrative prosthetics technology as an alternative to existing methods. An osseointegrative finger exoprosthetics system has been developed, consisting of an implantable part and a cosmetic part, implanted in a minimally invasive single-stage operation. Design analysis was run using numerical modeling and showed that the system can withstand loads with a safety factor of 7–25 and can be used to perform basic tasks. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the survival rates of dental implants with a hybrid macrostructure and the surface biomimetically coated with nanohydroxyapatite, placed in horizontally atrophic maxillae previously submitted to the guided bone regeneration (GBR) procedure, associated with the use of a deproteinized bovine bone graft (DBB). Methods: Twenty-five patients who received 196 implants were involved in this study. First, these patients were submitted to GBR procedures and maxillary sinus lift, where DBB was used as the grafting material. The dental implants were placed after a minimum period of 6 months of the grafting procedures. The patients were followed up every six months and clinical/radiographic examinations were performed to assess the implants, using the following indicators as a reference: (1) Absence of mobility; (2) Absence of pain. Data about the age, surgery time, smoking status, implant size, and time between the grafting procedure and implant placement were correlated with implant failures. Results: Twelve implants failed, generating a survival rate of 94.23%. None of the variables analysed correlated with the implant failures. Conclusion: Implants with a hybrid macrostructure and surface biomimetically coated with nanohydroxyapatite present good survival rates in horizontally atrophic maxillae grafted with DBB. [ABSTRACT FROM AUTHOR]

Background: To avoid cortical compression, several implant systems have included in the protocol dedicated drills aimed at widening the cortical region of osteotomy. However, the manual execution of this operation does not guarantee the necessary precision. Hence, the present study aimed to determine the optimal size of the recipient site at the level of the alveolar crest in relation to the size of the coronal region of the implant to achieve the best healing result. Materials and methods: Blades of different diameters were incorporated into the coronal part of the implant to prepare the cortical region of the mandibular alveolar bone crest in different dimensions in relation to the collar of the implant. The differences in diameter of the blades in relation to the collar of the implant were as follows: one control group, -175 μm, and three test groups, 0 μm, + 50 μm, or + 200 μm. Results: The marginal bone loss (MBL) at the buccal aspect was 0.7 mm, 0.5 mm, 0.2 mm, and 0.7 mm in the − 175 μm, 0.0 μm, + 50 μm, + 200 μm groups, respectively. The differences were statistically significant between group + 50 μm and control group − 175 μm (p = 0.019), and between + 50 μm and + 200 μm (p < 0.01) groups. The level of osseointegration at the buccal aspect was more coronally located in the test groups than in the control group, whereas the bone-to-implant contact percentage was higher in the + 50 μm and + 200 μm groups. However, these differences were not statistically significant. Conclusions: The lowest bone crest resorption and highest levels of osseointegration were observed in the 0.0 μm and + 50 μm groups. The cortical region where the blades had performed their cutting action showed regular healing with perfect hard and soft tissues sealing in all the groups. Cortical blades gathered bone particles, particularly in the + 200 μm group, which were incorporated into the newly formed bone. The results from the present experiment provide support to the use of blades that produce a marginal gap of 50 μm after implant insertion. [ABSTRACT FROM AUTHOR]

This study aims to answer the question: Which are superior—conventional or short femoral stems?. An Optymis stem was used as a short-femoral stem, and an Accolade II stem was used as a conventional-femoral stem. There were 95 patients in the short femoral stem group (Group 1) and 90 in the conventional stem group (Group 2). The SF-36 Life Quality Score, thigh pain, and the Harris Hip Score were used to evaluate the patients' clinical outcomes. Pre-operative, immediate post-operative, and final follow-up x-rays were used for radiological evaluation. Stem varus/valgus alignment, hip offset changing, acetabular anteversion/inclination changing, femoral migration, acetabular migration, periarticular ossification, and osteointegration evaluation were assessed for both groups. The mean follow-up time was 5.5 years for Group 1 and 5.2 years for Group 2. No significant difference existed between the two groups in terms of clinical scores (Harris Hip Score, SF-36). Thigh pain was significantly higher in Group 2 (p = 0.0001). As for radiological parameters, Group 1 exhibited more varus position-related results. In terms of angular stability, Group 1 was found to be more unstable than Group 2 (p = 0.0001). The power to reconstruct femoral offset was superior in Group 1. Periarticular ossification was more frequent in Group 2. Femoral osteointegration was denser proximally in Group 1 and distally in Group 2. When mid-term radiological and clinical results of both femoral stems are evaluated, they have no superiority over each other. [ABSTRACT FROM AUTHOR]

Considering the biological activity of osteoblasts is crucial when devising new approaches to enhance the osseointegration of implant surfaces, as their behavior profoundly influences clinical outcomes. An established inverse correlation exists between osteoblast proliferation and their functional differentiation, which constrains the rapid generation of a significant amount of bone. Examining the surface morphology of implants reveals that roughened titanium surfaces facilitate rapid but thin bone formation, whereas smooth, machined surfaces promote greater volumes of bone formation albeit at a slower pace. Consequently, osteoblasts differentiate faster on roughened surfaces but at the expense of proliferation speed. Moreover, the attachment and initial spreading behavior of osteoblasts are notably compromised on microrough surfaces. This review delves into our current understanding and recent advances in nanonodular texturing, meso-scale texturing, and UV photofunctionalization as potential strategies to address the "biological dilemma" of osteoblast kinetics, aiming to improve the quality and quantity of osseointegration. We discuss how these topographical and physicochemical strategies effectively mitigate and even overcome the dichotomy of osteoblast behavior and the biological challenges posed by microrough surfaces. Indeed, surfaces modified with these strategies exhibit enhanced recruitment, attachment, spread, and proliferation of osteoblasts compared to smooth surfaces, while maintaining or amplifying the inherent advantage of cell differentiation. These technology platforms suggest promising avenues for the development of future implants. [ABSTRACT FROM AUTHOR]

Given the hierarchical nature of bone and bone interfaces, osseointegration, namely the formation of a direct bone-implant contact, is best evaluated using a multiscale approach. However, a trade-off exists between field of view and spatial resolution, making it challenging to image large volumes with high resolution. In this study, we combine established electron microscopy techniques to probe bone-implant interfaces at the microscale and nanoscale with plasma focused ion beam-scanning electron microscopy (PFIB-SEM) tomography to evaluate osseointegration at the mesoscale. This characterization workflow is demonstrated for bone response to an additively manufactured Ti-6Al-4V implant which combines engineered porosity to facilitate bone ingrowth and surface functionalization via genistein, a phytoestrogen, to counteract bone loss in osteoporosis. SEM demonstrated new bone formation at the implant site, including in the internal implant pores. At the nanoscale, scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the gradual nature of the bone-implant interface. By leveraging mesoscale analysis with PFIB-SEM tomography that captures large volumes of bone-implant interface with nearly nanoscale resolution, the presence of mineral ellipsoids varying in size and orientation was revealed. In addition, a well-developed lacuno-canalicular network and mineralization fronts directed both towards the implant and away from it were highlighted. [ABSTRACT FROM AUTHOR]

Objective: To describe the clinical and radiographic performance and survival rate of a new two-piece ceramic implant system after at least 12 months of follow-up. Materials and methods: Sixty-five implants were placed and followed up for at least 12 months (12.3 ± 1.5), in 50 patients. The implants were installed both in fresh extraction sockets and in healed sites and received provisional restoration when the clinical insertion torque was greater than 35Ncm. The primary results describe the survival rate of these implants. Clinical performance was evaluated through the evaluation of the Pink Esthetic Score (PES) and the degree of satisfaction of the patients. Bone loss was measured through radiographic measurements of the marginal bone loss in the mesial (MBLM) and distal (MBLD) sites. Results: The survival rate was 98.5%. The average MBLM was 0.24 mm (± 0.53) and the MBLD was 0.27 mm (± 0.57). A statistical difference was observed only when comparing immediate implants with delayed ones (MBLM – p = 0.046 and MBLD - p = 0.028) and when they received immediate provisionalization or not (MBLM - p = 0.009 and MBLD - p = 0.040). The PES before the intervention (T0) was 13.4 (± 0.8) and the PES at T2 (12-month follow-up) was 12.9 (± 1.5) (p = 1.14). Conclusion: The new two-piece ceramic implant used in the present study showed predictable and reliable results, similar to those found with titanium implants after one year of follow-up. Clinical relevance: These implants can be used as an alternative to titanium implants in terms of the marginal bone loss and the degree of patient satisfaction. [ABSTRACT FROM AUTHOR]

Objectives: Bioactive surfaces were designed to increase the interaction between the surface and the cells. This may speed up the biological stability and loading protocols. Materials and methods: 36 patients with D3-D4 bone density were recruited and allocated into two groups. 30 bioactive (test group) and 30 traditional (control group) surfaced implants were placed. Insertion torque value (Ncm), insertion torque curve integral (cumulative torque, Ncm), torque density (Ncm/sec), implant stability quotient (ISQ) measured at three timepoints (baseline (T0), 30 (T30) and 45 (T45) days after surgery), and marginal bone loss (MBL) at 6 months of loading were assessed. Results: The mean ISQ and standard deviation at T0, T30, T45 were respectively 74.57 ± 7.85, 74.78 ± 7.31, 74.97 ± 6.34 in test group, and 77.12 ± 5.83, 73.33 ± 6.13, 73.44 ± 7.89 in control group, respectively. Data analysis showed significant differences between groups in ΔISQ at T0-T30 (p = 0.005) and T30-T45 (p = 0.012). Control group showed a significant decrease in ISQ at T30 (p = 0.01) and T45 (p = 0.03) compared to baseline, while no significant change was observed in test group. Due to the stability of the ISQ value ≥ 70, 26 test group and 23 control group implants were functionally loaded after 45 days. Conversely, due to the ISQ < 70 at T45, four test group implants and one control group implant were loaded after 90 days, and 6 control group implants were loaded after 180 days. Neither insertion torque nor ISQ at baseline were correlated with bone density (in Hounsfield units). There was no significant correlation between cumulative torque and ISQ at baseline. There was a significant positive slope in the correlation between torque density and ISQ at baseline, more accentuated in D3 than D4. This correlation remained significant for the test group in D3 bone at day 30 and 45 (p < 0.01 in both time frames), but not in D4 bone, and it was not significant in CG. Conclusions: The bioactive surface showed better behavior in terms of implant stability in D3-D4 bone quality in the early stages of bone healing. Clinical relevance This study demonstrated that the transition from primary to secondary stability is improved using bioactive surface, especially in cases of poor bone environment (D3/D4 bone). [ABSTRACT FROM AUTHOR]

Bone fracture healing is a challenging process, due to insufficient and slow tissue repair. Sufferers from bone fractures struggle with one-third of nonunion, display graft rejection, high-costed implantation, or chronic pain. Novel advances in tissue engineering presented promising options for this strain. Biomaterials for bone repair allow accelerated regeneration, osteoblastic cell activation, and enhanced bone remodeling. There is a wide range of biomaterials that are biocompatible, bioresorbable, and biodegradable and used for bone tissue regeneration, promoting osteoconductive and osteoinductive properties. The main aim of bone tissue engineering is to generate rapid and optimal functional bone regeneration through a combination of biomaterials, growth factors, cells, and various agents. Recently bone tissue engineering has been attracted to the use of bioactive glass scaffolds incorporated with polymers and patient-specific fabrication of the bone healing material by 3D bioprinting. There are promising future outcomes that were reported by several research. The present review provides an outlook for recent most common biomaterials in bone tissue engineering suggesting bone tissue engineering practices should have been proceeded to clinical application. [ABSTRACT FROM AUTHOR]

Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent "dichotomy kinetics" of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field. [ABSTRACT FROM AUTHOR]

The review critically evaluates the current state of studies investigating laser irradiation for modifying titanium surfaces to enhance the biointegration of dental implants. Laser modification is a rapidly evolving physicochemical surface modification process with the potential to revolutionize dental implant technology. A thorough search of electronic databases, including PubMed, Science Direct, MEDLINE, and Web of Knowledge, was conducted to identify relevant articles. The review focuses on the surface features of laser-modified implants, encompassing in vitro cell culture experiments, rare animal experiments, and limited clinical trials. Of the 26 selected sources, 21 describe surface features, while only two involve in vivo human experiments. The review highlights the lack of long-term clinical experience and calls for further research to mature these technologies. Despite the absence of a consensus on optimal laser types and settings, the overall results are promising, with few negative outcomes. As research in laser irradiation of titanium surfaces progresses, significant advancements in dental implant technology and improved patient well-being are anticipated. [ABSTRACT FROM AUTHOR]

Osseointegrated implants have been developed to allow direct skeletal fixation of a prosthesis as an alternative to traditional socket-fitted prostheses for patients who have suffered from a major limb amputation. The implants contribute to improvements in functional outcome and quality of life and radiological evaluation plays a crucial role in pre- and post-operative assessment. This article acts as a guide for radiologists who may be tasked with providing the radiological information required by surgeons and prosthetists. We also look at the radiological appearances of complications that may arise in patients treated with an osseointegrated implant. Plain X-rays are used to screen patients who wish to undergo treatment. Limb-length X-rays are then used to measure the length of any residual bone, and comparisons can be made with the normal side (if present). From this, decisions about the likely size of the implant and the need for further amputation can be made. CT scans enable accurate assessment of the medullary cavity and cortical thickness. Post-operatively, plain X-rays form the mainstay of the routine monitoring of the bone-implant interface. Potential complications include infection, aseptic loosening, mechanical fracture of the implant and periprosthetic fracture. Infection and aseptic loosening can be seen as a lucency at the bone-implant interface which (if left untreated) can lead to loss of the implant. Implant and periprosthetic fractures are radiographically obvious. Radiologists involved in the care of patients undergoing treatment with an osseointegrated implant should become familiar with the imaging requirements so they can contribute to optimal patient outcomes. [ABSTRACT FROM AUTHOR]

Background: Healing of critical-size defects is a well-known problem that has been challenged in several studies. The aim of the experiment was to evaluate bone formation and osseointegration of implants installed in critical defects of the mandibular body simultaneously grafted with Bio-Oss® or Cerabone®. Material and methods: Defects, 10 mm wide and 3 mm deep, were prepared at both lateral aspects of the mandible in 12 rabbits. One implant was installed in the center of the defect, and bovine xenografts produced either at low (Bio-Oss®; Low-T) or high (Cerabone®; High-T) temperatures were used to fill the defects. A collagen membrane was placed to cover the sites. Healing was evaluated 10 weeks after surgery. Results: In both groups, most sites showed optimal healing with closure of the coronal entrance of the defects. However, residual defects occupied by soft tissues and biomaterial particles were observed, even though generally limited to some regions of the defect. Osseointegration of the implant surface in the region of the defect was poor in both groups. Conclusions: Circumferential marginal critical-size defects around implants filled with bovine xenografts presented regions with a complete healing in both groups. However, the healing was not complete at all regions in most defects; therefore, a complete optimal healing of critical-size marginal defects cannot be predicted. [ABSTRACT FROM AUTHOR]

Purpose: Osteoporotic individuals who have dental implants usually require a prolonged healing time for osseointegration due to the shortage of bone mass and the lack of initial stability. Although studies have shown that intermittent teriparatide administration can promote osseointegration, there is little data to support the idea that pre-implantation administration is necessary and beneficial. Methods: Sixty-four titanium implants were placed in the bilateral proximal tibial metaphysis in 32 female SD rats. Bilateral ovariectomy (OVX) was used to induce osteoporosis. Four major groups (n = 8) were created: PRE (OVX + pre-implantation teriparatide administration), POST (OVX + post-implantation administration), OP (OVX + normal saline (NS)) and SHAM (sham rats + NS). Half of rats (n = 4) in each group were euthanized respectively at 4 weeks or 8 weeks after implantation surgery, and four major groups were divided into eight subgroups (PRE4 to SHAM8). Tibiae were collected for micro-CT morphometry, biomechanical test and undecalcified sections analysis. Results: Compared to OP group, rats in PRE and SHAM groups had a higher value of insertion torque (p < 0.05). The micro-CT analysis, biomechanical test, and histological data showed that peri-implant trabecular growth, implants fixation and bone-implant contact (BIC) were increased after 4 or 8 weeks of teriparatide treatment (p < 0.05). There was no statistically difference in those parameters between PRE4 and POST8 subgroups (p > 0.05). Conclusions: In osteoporotic rats, post-implantation administration of teriparatide enhanced peri-implant bone formation and this effect was stronger as the medicine was taken longer. Pre-implantation teriparatide treatment improved primary implant stability and accelerated the osseointegration process. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the effect of nanoparticles (NPs) of a plant extract on implant osseointegration in vivo. NPs of the Cissus quadrangularis (CQ) extract were synthesized. Twenty Wistar rats were included in the study. The test group (n = 5) had NPs-incorporated, the control group (n = 5) had no incorporation of NPs, and the sham group (n = 5) did not have implants placed. The toxicity profile of NPs was carried out by biochemical analysis before and after the implant placement. The rate of integration was assessed using Cone Beam Computed Tomography (CBCT), Digital X-ray, histology, and scanning electron microscopy (SEM) at intervals of 2, 4, and 6 weeks. Statistical significance between the groups was determined by Analysis of Variance (ANOVA) (p < 0.05) and the differences were uncovered with post hoc Tukey's test. Results: Radiographs showed that the bone density around implants with NPs was considerably higher than those without NPs. The osteoid seam along the implant surface was found to be considerably higher in the test group. A noteworthy increase was observed in the bone formation around the implants in bone samples belonging to the test group. Comparing the values at different time intervals, the highest serum Alkaline phosphatase (ALP) activity was noted in the test group after six weeks and the lowest serum Acid phosphatase (ACP) activity was documented in the test group after 6 weeks. Conclusion: The test group samples exhibited an osseointegration rate of less than 2 weeks thus demonstrating CQ NPs to be a potent osteoinductive agent. [ABSTRACT FROM AUTHOR]

Cranial reconstructions are essential for restoring both function and aesthetics in patients with craniofacial deformities or traumatic injuries. Titanium prostheses have gained popularity due to their biocompatibility, strength, and corrosion resistance. The use of Superplastic Forming (SPF) and Single Point Incremental Forming (SPIF) techniques to create titanium prostheses, specifically designed for cranial reconstructions was investigated in an ovine model through microtomographic and histomorphometric analyses. The results obtained from the explanted specimens revealed significant variations in bone volume, trabecular thickness, spacing, and number across different regions of interest (VOIs or ROIs). Those regions next to the center of the cranial defect exhibited the most immature bone, characterized by higher porosity, decreased trabecular thickness, and wider trabecular spacing. Dynamic histomorphometry demonstrated differences in the mineralizing surface to bone surface ratio (MS/BS) and mineral apposition rate (MAR) depending on the timing of fluorochrome administration. A layer of connective tissue separated the prosthesis and the bone tissue. Overall, the study provided validation for the use of cranial prostheses made using SPF and SPIF techniques, offering insights into the processes of bone formation and remodeling in the implanted ovine model. [ABSTRACT FROM AUTHOR]

In order to solve the problems of serious tool wear and poor processing quality in the process of titanium alloy processing, cutting-edge dulling and surface texturing technology are applied to improve the service performance of cutting tools. Designing multiple density micro-textured tool according to the friction form of the tool-chip contact area is an essential factor in ensuring the cutting performance of tool. In this paper, firstly, the influence of laser parameters on the temperature field and stress field of the material is analyzed, and the optimized laser parameters are obtained. Secondly, the experimental milling platform of multiple distribution density micro-texture ball-end milling cutter under the action of cutting edge is built. The influence of micro-texture and cutting-edge parameters on tool milling performance and work-piece quality is analyzed, and the mechanism is revealed. Finally, the parameters are optimized based on the simulated annealing algorithm. The results show that the main parameters affecting the milling force, tool wear, and work-piece surface roughness are the edge radius and the micro-texture diameter of the stickiness area. It has opened up new ideas for the efficient cutting of titanium alloy. [ABSTRACT FROM AUTHOR]

Purpose: In the over-80 s, femoral bone is often osteoporotic and unlikely to be conducive to periprosthetic bone rehabitation. This observation often leads to cemented fixation for hemiarthroplasty in femoral neck fracture. Hydroxyapatite is a bioactive coating that has already demonstrated its osteoinductive properties. Our hypothesis is that hydroxyapatite enables prosthetic osseointegration in patients over 80, as well as periprosthetic cortical thickening. The objective was to evaluate the osseointegration of a hydroxyapatite-coated femoral stem in femoral neck fractures in the over-80 s, and the evaluation of the periprosthetic bone regeneration permitted by hydroxyapatite. Methods: This was a retrospective study. Osseointegration and periprosthetic bone regeneration were assessed on pre-operative, immediate post-operative and last follow-up radiographs with Engh score, O-SS score, cortical index, Canal Bone Ration (CBR) and Canal Fill Ratio (CFR). Results: One hundred and forty-six patients were included. At last follow-up, 99.3% (n = 145) of stems were osseointegrated. The mean Engh score was 19.9 [SD 3.1]. The mean O-SS score was 19.1 [SD 2.4], corresponding to very good osseointegration. The mean CBR at last follow-up was 0.48 [SD 0.07], corresponding to a non-osteoporotic femur. There was a significant difference with pre-operative CBR (p < 0,001). The pre-operative cortical index and the index at the last follow-up were significantly different for all levels of measurement (p < 0,001). The CFR at last follow-up was also significantly different with the post-operative CFR (p < 0,001). Conclusion: This study shows the value of using a hydroxyapatite-coated stem on senile, osteoporotic bone to improve cortical thickness along the entire length of femoral bone. [ABSTRACT FROM AUTHOR]

Understanding and predicting the failure modes of transversely isotropic (TI) rocks is essential for designing stable structures and evaluating rock failure incidents, including ground falls, slope stability, and landslides. Compared to isotropic intact rock, TI intact rock exhibits distinct failure modes. Until now, the failure mode of TI rocks has often been related to layer orientation and confinement pressure, with little consideration given to micro-scale parameters. This study investigates how layer orientation and grain size influence the failure mode of layered sandstone under confined and unconfined conditions. A comprehensive laboratory experiments involved 105 layered sandstone samples, featuring variations in grain sizes (fine, medium, and coarse), application of five distinct confining pressures, and testing at seven different orientations. Through rigorous analyses of the post-failure layered sandstone using a random forest classification method, this study developed a predictive chart capable of determining TI rock failure mode based on layer orientation and confinement pressure. Intriguingly, the study also underscores that grain size exerts an insignificant impact on influencing these failure modes. The resultant predictive chart is expected to significantly enhance our comprehension and interpretation of rock failure in both laboratory and field applications, offering invaluable insights for engineering structures associated with TI rocks. Highlights: Confining pressure and layer orientation significantly influence the failure modes of transversely isotropic rocks, with grain size demonstrating negligible impact. The Random Forest Method constructed a predictive failure mode chart, effectively classifying regions into sliding/non-sliding and tensile/shear boundaries. The classification identifies three primary groups of failure modes: layer failure, matrix failure, and mixed failure. The classification of Type 1 and Type 2 mixed failures between the sliding and non-sliding regions, enhancing the granularity of classification. [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]

Objective: To assess the impact of enhancement filters on the formation of halo artifacts in radiographs of dental implants obtained with a complementary metal oxide semiconductor (CMOS) system. Methods: Digital radiographs of dental implants placed in dry human mandibles were processed with the Noise Reduction smoothing filter, as well as the Sharpen 1, Sharpen 4, and Sharpen UM high-pass filters available in the CLINIVIEW™ software (Instrumentarium Dental, Tuusula, Finland). Subjective analysis involved evaluating the left, right, and apical surfaces of each implant for the presence of much, few, or no halo. The objective analysis involved measurement of the halo area using the Trainable Weka Segmentation plugin (ImageJ, National Institutes of Health, Bethesda, MD, USA). Data were analyzed using Friedman’s test (subjective analysis) and ANOVA (objective analysis) (α = 5%). Results: In the subjective evaluation, the Sharpen 4 filter produced more radiographs with much halo present, and in the objective evaluation, a bigger halo area when compared to the original images and the Noise Reduction filter for all surfaces (p < 0.05). Conclusions: When evaluating dental implants, priority should be given to original images and those enhanced with smoothing filters since they exhibit fewer halo artifacts. Clinical relevance: Post-processing tools, such as enhancement filters, may improve the image quality and assist some diagnostic tasks. However, little is known regarding the impact of enhancement filters in halo formation on CMOS systems, which have been increasingly used in dental offices. [ABSTRACT FROM AUTHOR]

We studied the interaction of human buccal mesenchymal stem cells (MSCs) and osteoblasts differentiated from them with the surface of titanium samples. MSCs were isolated by enzymatic method from buccal fat pads. The obtained cell culture was presented by MSCs, which was confirmed by flow cytometry and differentiation into adipocytes and osteoblasts. Culturing of buccal MSCs on titanium samples was accompanied by an increase in the number of cells for 15 days and the formation of a developed network of F-actin fibers in the cells. The viability of buccal MSCs decreased by 8 days, but was restored by 15 days. Culturing of osteoblasts obtained as a result of buccal MSC differentiation on the surface of titanium samples was accompanied by a decrease in their viability and proliferation. Thus, MSCs from buccal fat pads can be used to coat implants to improve osseointegration during bone reconstruction in craniofacial surgery and dentistry. To improve the integration of osteoblasts, modification of the surface of titanium samples is required. [ABSTRACT FROM AUTHOR]

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Purpose: Ozone is a potent antioxidant agent which presents an important antimicrobial action and many other biological effects. Although ozone therapy has been widely described and summarized in several other Dentistry areas recently, the studies concerning Dental Implantology have not been systematically compiled and evaluated. Thus, the present study aimed to evaluate the effectiveness of ozone therapy in dental implant procedures. Methods: MEDLINE (via PUBMED), Cochrane Central Register of Controlled Trials (CENTRAL), and OpenGrey databases were searched (up to, and including, January 23, 2023) for studies in the English language. In addition, the reference lists of the articles were manually examined. Only interventional studies (controlled clinical trials, randomized or not) were considered eligible for inclusion. The risk of bias in each included study was assessed using the Cochrane tool for assessing risk of bias in randomized trials – version 2. Results: 71 potentially eligible records were retrieved but only 5 articles were evaluated and considered eligible for inclusion. Among the studies, 2 addressed clinical situations related to implant insertion, and 3 involved pathological conditions affecting implants in function. Furthermore, only one randomized clinical trial was categorized as low risk of bias. Conclusion: The adjuvant use of ozone therapy may positively affect some outcomes in Implant Dentistry, both in treating pathological conditions and conducting rehabilitation (implant installation, secondary implant stability). However, as most studies have a high risk of bias and high heterogeneity, a definitive conclusion cannot be drawn. [ABSTRACT FROM AUTHOR]

Purpose: This systematic review aimed to determine whether differences in the macro-geometry of titanium implants promote changes in osseointegration. Material and method: SCOPUS, PubMed/Medline, Web of Science, and EMBASE databases were searched in June 2021. In addition, it was performed a manual search of the reference lists of the included articles. Eligibility criteria were in vivo studies that addressed the effect of titanium implant macro-geometry on osseointegration, studies that evaluated periodontally healthy models, and papers indexed in Journal Citation Reports. Results: The database search resulted in 1037 articles. Of the 19 articles selected for full reading, 16 remained in this systematic review. These had a high heterogeneity making it hard to perform statistical analysis of the data, so a descriptive analysis was performed. Conclusions: Based on the studies included in this systematic review, implant macro-geometry provides influences on osseointegration. In this sense, the various isolated characteristics (thread type, thread pitch, thread depth, face angle) should be studied so that the implant geometry can balance the compressive stress and tensile stress and produce a minimum shear force. [ABSTRACT FROM AUTHOR]

Background: The size of dental implants is a key success factor for appropriate osseointegration. Using shorter implants allows the possibility of avoiding complex surgical procedures and reduces the morbidity of treatment. Shorter implants also enable implant-prosthetic rehabilitation after maxillofacial reconstructions where only limited bone is available. In this study, the success rates of short implants were examined and compared to those of standard-sized implants. Methods: Patients who received dental implants between 2007 and 2016 at the Department of Oro-Maxillofacial Surgery and Stomatology Semmelweis University were enrolled in the study. Several clinical parameters were recorded and supplemented with radiological examinations. The data were statistically analysed. Results: Thirty-four patients with a total of 60 implants were included. The average time after prosthetic loading was 39.33 ± 21.96 months in the group with 8-mm implants and 41.6 ± 27.5 months in the group with > 8-mm implants. No significant differences were observed between the two groups in terms of probing depth (short implants, 2.84 ± 0.09 mm; standard implants, 2.91 ± 0.35 mm) or mean marginal bone loss (short implants, 1.2 ± 1.21-mm mesially and 1.36 ± 1.47-mm distally; standard implants: 0.63 ± 0.80-mm mesially and 0.78 ± 0.70-mm distally). Conclusions: In this study, the success rate of short dental implants was comparable to that of standard-sized implants. Consequently, it can be claimed that the long-term success of short dental implants does not differ significantly from the long-term success of standard implants. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the implant survival rate, mechanical complications, and reported patient outcomes of bone-anchored prostheses for patients with lower limb amputation in France after 1–15 years of follow-up. Methods: This retrospective cohort study included patients who underwent surgery at a single center in France between 2007 and 2021. The primary outcomes were the implant survival rate and functional scores assessed by the Questionnaire for Transfemoral Amputees (Q-TFA). Secondary outcomes were adverse events that occurred during follow-up. Results: The cohort consisted of 20 bone-anchored prostheses in 17 patients. The main level of amputation was transfemoral (82%, n = 14). The main reason for amputation was trauma (n = 15). The mean age at amputation was 32 (range 15–54) years, and the mean age at the first stage of osseointegration was 41 (range 21–58) years. The Kaplan–Meier survival curve showed respective survival rates of 90%, 70%, and 60% at 2, 10, and 15 years. All Q-TFA scores were significantly improved at last the follow-up. Eleven patients (65%) experienced mechanical complications. In total, 37 infectious events occurred in 13 patients (76%), mainly comprising stage 1 infections (68%, n = 25). Only two cases of septic loosening occurred (12%), leading to implant removal. Conclusion: This is the first French cohort of bone-anchored prostheses and among the series with the longest follow-up periods. The findings indicate that bone-anchored prostheses are safe and reliable for amputee patients who have difficulties with classic prostheses. [ABSTRACT FROM AUTHOR]

Purpose: The acquisition of osseointegration during implant therapy is slower and poorer in patients with diabetes compared with healthy persons. The serum concentration of adiponectin in patients with type II diabetes is lower than that of healthy persons via the suppression of AMP-activated protein kinase (AMPK). Therefore, we hypothesized that the AMPK activation enhances bone formation around implants, resulting in the improved acquisition of osseointegration. The purpose of this study was to evaluate the impact of AMPK activation on osteoblast differentiation and its mechanism of downstream signaling on titanium disc (Ti). Methods: Confluent mouse pre-osteoblasts (MC3T3-E1) cells (1 × 105 cells/well) were cultured with BMP-2 for osteoblast differentiation, in the presence or absence AICAR, an AMPK activator. We examined the effects of AMPK activation on osteoblast differentiation and the underlying mechanism on a Ti using a CCK8 assay, a luciferase assay, quantitative RT-PCR, and western blotting. Results: Although the proliferation rate of osteoblasts was not different between a Ti and a tissue culture polystyrene dish, the addition of AICAR, AMPK activator slightly enhanced osteoblast proliferation on the Ti. AICAR enhanced the BMP-2-dependent transcriptional activity on the Ti, leading to upregulation in the expression of osteogenesis-associated molecules. AICAR simultaneously upregulated the expression of autophagy-associated molecules on the Ti, especially LC3-II. AdipoRon, an adiponectin receptor type1/type2 activator activated AMPK, and upregulated osteogenesis-associated molecules on Ti. Conclusions: AMPK activation enhances osteoblast differentiation on a Ti via autophagy, suggesting that it promotes the acquisition of osseointegration during implant therapy. [ABSTRACT FROM AUTHOR]

This study is aimed to evaluate the galvanic corrosion of a newly designed TiMg dental implant. The TiMg composite was tested in two forms: (1) cylinders (TiMg cyl) and (2) dental implants (TiMg DI). Surface roughness was measured using a confocal microscope. The electrochemical behavior was determined in a Hank's balanced salt solution (HBSS) by the open-circuit potential (OCP), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) measurements. Surfaces after corrosion were examined by a scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS). OCP of TiMg cyl and TiMg DI increased in the noble direction, indicating the formation and growth of a base film on their surfaces. After 2-h immersion, TiMg cyl had higher values of iCorr and RCorr compared with those of TiMg DI. After 24-h immersion, a prominent reduction in the values of iCorr and RCorr was observed, and ECorr shifted positively. The Nyquist plots of TiMg cyl and TiMg DI show capacitive loops that tended to close after 2-h exposure. As the time extended, TiMg DI showed higher corrosion resistance compared with that of TiMg cyl, and the linear diffusion response arose from the formation and dissolution of chemically non-stable by-products caused by the hydrogen evolution. In such a case, the involved reaction was controlled by charge transfer and diffusion processes. The formation of a film composed of stable CAp species that attached directly to the surface and chemically non-stable by-products that included (Mg3(PO4)2) and Mg(OH)2 was demonstrated. To conclude, the obtained results revealed that TiMg DI of a complicated threaded design had a more stable passive film and higher corrosion resistance in HBSS compared with those of TiMg cyl of a cylindrical design. These findings have the utmost importance for the fabrication of dental implants. [ABSTRACT FROM AUTHOR]

Porous dental implants are clinically used, but the mechanism of load distribution for stepped implant shaft surrounded by compliance bushings is still not known, especially for different bone conditions. The aim of the study was to assess the impact of the design of a dental implant with compliance bushings (CBs) on the occlusal load distribution during primary and secondary stability using finite element simulation (FEA), with a distinction between low and high quality cervical support under primary stability. The FEA of the oblique occlusal load transfer (250 N; 45°) was carried out for implants under variable bone conditions. The stepped shaft in the intermediate part of the dental implant was surrounded by CBs with an increasing modulus of elasticity of 2, 10 and 50 GPa. With a smaller Young's modulus of the bushings the increase of stress in the trabecular bone indicated that more bone tissue can be protected against disuse. The beneficial effect for the trabecular bone derived from the reduction of the stiffness of the bushings in relation to the loss of the implant's load bearing ability can be assessed using the FEM method. [ABSTRACT FROM AUTHOR]

Dental implants are becoming an increasingly important part of modern dental treatment. Developing an optimal implant surface design can improve osseointegration. Promising to increase the rate of osseointegration is the use of extracorporeal shock wave therapy, which has proven itself for the treatment of fractures, bone defects, and bone tissue regeneration during surgery and arthroplasty. This work aims at a numerical investigation of the effects of low-energy shock wave therapy of various intensities on the mechanical behavior of dental implants and surrounding bone tissues, taking into account the physiological characteristics in the area of dental implant placement. Modeling was carried out using the method of movable cellular automata. The results of computer simulation showed that the conditions for the regeneration of bone tissues at the near-contact zone with the implant of the jaw segment are created by a shock wave with intensity greater than 0.1 mJ/mm2. [ABSTRACT FROM AUTHOR]

Hip implants face a significant challenge due to their limited lifespan, a concern amplified by the rising human life expectancy. Lattice structures have demonstrated the ability to provide precise control over geometry, thereby significantly enhancing implant performance. This paper introduces the development of graded additively manufactured Ti6Al4V lattice structures for orthopaedic implants. The objective focuses on developing a graded lattice unit cell design mirroring human bone properties, emphasising high surface curvature and design versatility to improve mechanical and biomedical properties, specifically osseointegration and stress shielding. The study involves modelling and grading simple cubic (SC) and body-centred cubic (BCC) lattice structures with various geometries and graded conditions and conducting compressive tests to identify the optimal configuration. The results showed that filleting was found to be the mechanical strength. On the other hand, BCC lattice structures demonstrated superior performance compared to SC structures. The optimised structure with a pore size of 400 µm provided an elastic modulus of 15.7 GPa, yield strength of 296 MPa and compressive strength of 530 MPa. This graded lattice design approach provides a promising technique for enhancing hip implant performance, offering potential improvements. [ABSTRACT FROM AUTHOR]

The surface properties of artificial implants are responsible for contact, primary fixation, intermediate bonding and future stability with the host tissue and their suitable alteration can improve functionality of the implants. Here, a picosecond pulsed laser was employed to alter the surface properties of a widely used biomaterial, Ti64. Three types of samples with variation in average surface roughness, wettability and presence of oxide layer were prepared by changing the laser fluence and pulse overlapping factor. The influence of change in surface properties on electrochemical behavior, bio-corrosion and cytocompatibility and ossiointegration of the sample were investigated. Comparative studies showed an improvement in anticorrosive behavior of Ti64 alloy after laser treatment that is confirmed from the open-circuit potential, Tafel analysis and impedance spectroscopy in simulated body fluid. Furthermore, the non-toxic nature of laser-treated surface was established and was confirmed from the cytotoxicity studies on U2OS osteosarcoma cells. Comparable number of cells with no changes in nuclear morphologies were found to be adhered on laser-treated samples. Growth of hydroxayaptite on all samples was monitored 25 days after their immersion in simulated body fluid. Along with improved osseointegration capability, the laser-treated sample at a fluence of 0.12 J/cm2 and 58% laser pulse overlapping factor exhibited superior performance in all other tested aspects. This shows that the chosen experimental parameters suitably modified the surface to enhance its biocompatibility in all tests performed in this study. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the osseointegration of implants with hydrophobic (HFB) and hydrophilic (HFL) surfaces in a murine model of high-dose bisphosphonates (BPs). Materials and methods: Sixty-four rats were randomly allocated into four groups: control group with HFB implants (CG-HFB), control group with HFL implants (CG-HFL), BP group with HFB implants (BP-HFB), and BP group with HFL implants (BP-HFL). Animals were euthanized after 15 and 45 days (n=8). The dependent variables assessed were the removal torque (biomechanical analysis), the bone volume around the implants (%BV/TV) (microtomographic analysis), the bone-implant contact (%BIC), the bone between the threads (%BBT) (histomorphometric analysis), and the expression of bone metabolism markers (immunohistochemistry analysis). Results: The CG-HFL and BP-HFL groups presented higher removal torque than the CG-HFB and BP-HFB implants. The %BIC of the CG-HFL surfaces was slightly higher than that of the CG-HFB implants. The BP-HFB and BP-HFL groups presented a higher %BIC than that of the CG-HFB and CG-HFL groups (p<0.001). BP therapy also increased the %BBT at both implant surfaces. Higher levels of ALP were observed in the matrix region of bone tissue on the HFL surfaces than on the HFB surfaces. Conclusion: Both surfaces enable osseointegration in rats under BP therapy. Clinical relevance: The study demonstrates that hydrophobic (HFB) and hydrophilic (HFL) implant surfaces can promote osseointegration in rats undergoing bisphosphonate therapy. The HFL surfaces exhibited improved biomechanical performance, higher bone-implant contact, and increased bone volume, suggesting their potential clinical relevance for implant success in individuals on bisphosphonate treatment. [ABSTRACT FROM AUTHOR]

The use of titanium implants as fixed supports following fractures in patients with OP can often result in sterile loosening and poor osseointegration. Oxidative stress has been shown to play a particularly important role in this process. While TSA has been reported to facilitate in vivo osteogenesis, the underlying mechanisms remain to be clarified. It also remains unclear whether TSA can improve the osseointegration of titanium implants. This study investigated whether TSA could enhance the osseointegration of titanium rods by activating AKT/Nrf2 pathway signaling, thereby suppressing oxidative stress. MC3T3-E1 cells treated with CCCP to induce oxidative stress served as an in vitro model, while an OVX-induced OP rat model was employed for in vivo analysis of titanium rod implantation. In vitro, TSA treatment of CCCP-treated MC3T3-E1 cells resulted in the upregulation of osteogenic proteins together with increased AKT, total Nrf2, nuclear Nrf2, HO-1, and NQO1 expression, enhanced mitochondrial functionality, and decreased oxidative damage. Notably, the PI3K/AKT inhibitor LY294002 reversed these effects. In vivo, TSA effectively enhanced the microstructural characteristics of distal femur trabecular bone, increased BMSCs mineralization capacity, promoted bone formation, and improved the binding of titanium implants to the surrounding tissue. Finally, our results showed that TSA could reverse oxidative stress-induced cell damage while promoting bone healing and improving titanium rods' osseointegration through AKT/Nrf2 pathway activation. [ABSTRACT FROM AUTHOR]

Aim: The challenge of distal femoral replacement (DFR) longevity remains a priority for orthopaedic oncologists as the overall survival and activity level of young patients with osteosarcoma continues to improve. This study hypothesized that increased extracortical osseointegration at the bone-implant shoulder (i.e., where the metal implant shaft abuts the femur) will improve stress transfer adjacent to the implant, as evidenced by reduced cortical bone loss, radiolucent line progression and implant failure in young patients (< 20 years) following DFR surgery. Methods: Twenty-nine patients of mean age 13.09 ± 0.56 years received a primary DFR. The clinical outcome of 11 CPS®, 10 GMRS®, 5 Stanmore® and 3 Repiphysis® implants was evaluated over a mean follow-up period of 4.25 ± 0.55 years. The osseous response to a bone-implant shoulder composed of either a hydroxyapatite-coated grooved ingrowth collar (Stanmore®), a porous metal coating (GMRS®) or a polished metal surface (Repiphysis®) was quantified radiographically. Results: All (100.0%) of the Stanmore® implants, 90.0% of GMRS®, 81.8% of CPS® and 33.3% of the Repiphysis® implants survived. Significantly increased extracortical bone and osseointegration were measured adjacent to the Stanmore® bone-implant shoulder when compared with the GMRS® and Repiphysis® implants (p < 0.0001 in both cases). Significantly decreased cortical loss was identified in the Stanmore® group (p = 0.005, GMRS® and p < 0.0001, Repiphysis®) and at 3 years, the progression of radiolucent lines adjacent to the intramedullarly stem was reduced when compared with the GMRS® and Repiphysis® implants (p = 0.012 and 0.026, respectively). Conclusions: Implants designed to augment osseointegration at the bone-implant shoulder may be critical in reducing short- (≤ 2 years) to mid- (≤ 5 years) term aseptic loosening in this vulnerable DFR patient group. Further longer-term studies are required to confirm these preliminary findings. [ABSTRACT FROM AUTHOR]

Introduction: In this retrospective study stabilities of 24 implants simultaneously placed at posterior maxillae with sinuses grafted by advanced platelet rich fibrin (A-PRF) and newly formed bone around them were evaluated. Patient and Methods: Fourteen augmented maxillary sinuses of 11 patients with a mean residual alveolar bone height of 4.55 mm were involved in this study. Maxillary sinus lifting via lateral window approach and implant site osteotomy were performed, and prepared A-PRF clots were used as sole graft material. Each of the implants was immediately placed with a good primary stability. Postoperative sixth month tomography images were compared with preoperative ones in order to calculate the gained bone height and implant stability quotient (ISQ) values were recorded. Results: The new vertical mean bone height of 24 implant sites was 12.21 mm with an implant survival rate of 100%. ISQ values of the implants were ranging from 62 to 75 with a mean value of 68. Statistically the diameter of implant did not have any effect on new bone formation and the ISQ values, however the length of them did. Conclusion: A-PRF as a graft material for sinus lifting with simultaneous implant placement is a reliable technique with its low cost and lack of immunogenic reaction risk. [ABSTRACT FROM AUTHOR]

Purpose of Review: This review summarizes current findings regarding limb amputation within the context of cancer, especially in osteosarcomas and other bony malignancies. We seek to answer the question of how amputation is utilized in the contemporary management of cancer as well as explore current advances in limb-sparing techniques. Recent Findings: The latest research on amputation has been sparse given its extensive history and application. However, new research has shown that rotationplasty, osseointegration, targeted muscle reinnervation (TMR), and regenerative peripheral nerve interfaces (RPNI) can provide patients with better functional outcomes than traditional amputation. Summary: While limb-sparing surgeries are the mainstay for managing musculoskeletal malignancies, limb amputation is useful as a palliative technique or as a primary treatment modality for more complex cancers. Currently, rotationplasty and osseointegration have been valuable limb-sparing techniques with osseointegration continuing to develop in recent years. TMR and RPNI have also been of interest in the modern management of patients requiring full or partial amputations, allowing for better control over myoelectric prostheses. [ABSTRACT FROM AUTHOR]

This work researches the synchronous effect of grain refinement, induced by cold caliber rolling (CCR), and surface modification by sandblasting and acid-etching (SLA/SLActive) on the mechanical, surface, biological properties, and osseointegration improvement of commercially pure titanium (CP-Ti grade 2) dental implants. First, high-strength nanostructured CP-Ti was produced by caliber rolling. Then, SLA and SLActive surface modification methods were applied on the surface of both the CP-Ti and the nanostructured one. Surface roughness tests presented the highest value of roughness for the SLActive surface. All the specimens were implanted into the femur of six healthy New Zealand rabbits, and their properties were studied for periods of 1 and 3 months. To investigate the osseointegration, micro-CT images were tracked. Both hematoxylin and eosin (H&E) and Masson's trichrome (TRI) histopathology evaluations were conducted on all the implanted samples. Increases in bone mineral density (BMD), bone mineral content (BMC), and bone volume fraction (BV/TV) were noted. H&E histopathology indicated an increase of osteogenesis for the SLA-nano implants. TRI histopathology showed an increase in collagen secretion and bone-to-implant contact (BIC) of the SLActive implants, which demonstrated their improved osseointegration. All these results proved the effectiveness of caliber rolling and SLActive methods on the osseointegration of titanium dental implants. [ABSTRACT FROM AUTHOR]

The objective of this study is to further investigate the feasibility of Zinc–Titanium implant as a potential implantable material in oral application in aspects of osteoblast biocompatibility, osteogenesis and osseointegration ability. First, we used plasma immersion ion implantation and deposition (PIIID) technology to introduce Zinc ion into pure Titanium surface, then we used X-ray photoelectron spectroscopy to analyze the chemical composition of modified surface layer; next, we used in vitro studies including immunological fluorescence assay and western blotting to determine responses between MG-63 osteoblast-like cell and implant. In vivo studies adopted pig model to check the feasibility of Zn–Ti implant. Results showed that in vitro and in vivo were consistent, showing that Zn ion was successfully introduced into Ti surface by PIIID technique. The chemical and physical change on modified plant resulted in the more active expressions of mRNA and protein of Type I collagen in MG-63 cells compared with non-treated implant, and the better integration ability of bones with modified implant. We confirmed the Zn–Ti implant owns the ability in promoting osteogenesis and osteointegration in early phase of implantation and is a qualified candidate in dentistry. The overview of our study can be depicted as follows. [ABSTRACT FROM AUTHOR]