Search Results (210)

Background and Clinical Significance: Maxillary sinus augmentation is a well-established surgical procedure for dental implant placement in the posterior maxilla when the residual alveolar bone height is insufficient. Traditionally, the lateral approach has been preferred in cases with less than 4 mm of bone; however, the crestal approach has emerged as a less invasive alternative, particularly with the advent of advanced techniques and tools such as hydraulic pressure systems and dedicated osteotomy kits. Case Presentation: This case report presents the clinical management of a 68-year-old female patient requiring rehabilitation of the right maxillary molars, where the residual bone height measured only 3.6 mm (in position 1.6) and 2.5 mm (in position 1.7). Using the CAS kit system with rounded drills and hydraulic pressure, a controlled crestal sinus elevation was performed, followed by simultaneous implant placement. Despite the extremely limited bone height, a final insertion torque of 30 Ncm was achieved for both implants, likely due to favorable sinus floor anatomy, under-preparation of the implant sites, and the use of tapered, macro-textured implants. Postoperative follow-up over three years showed stable bone levels and successful prosthetic rehabilitation with single crowns. Conclusions: This case report highlights the potential of the crestal approach in anatomically challenging scenarios. Proper planning, technique, and implant selection are mandatory to achieve predictable and long-lasting outcomes, even in cases previously considered contraindicated for this method. Further randomized controlled trials are needed to confirm this preliminary result. Full article

Background/Objectives: In reverse shoulder arthroplasty (RSA), precise K-wire positioning of the glenoid component is critical to prevent complications such as glenoid loosening or instability as well as premature implant failure. Optimal component placement must adhere to individualized preoperative plans to account for patient-specific anatomical conditions. Conventional methods often fail to achieve this level of accuracy, undermining the need for personalized medicine. Intraoperative navigation systems are growing in use to improve accuracy in orthopedic surgery. This study aimed to compare the accuracy of K-wire positioning in a 3D-printed model of the scapula using conventional versus navigated methods. Methods: We recruited 20 participants: 10 experienced surgeons and 10 inexperienced medical students. Each participant performed four K-wire drillings—two with conventional instruments and two with an intraoperative navigation system. A novel target system, BoneTrack3D, was used to measure accuracy. We assessed the absolute deviation of the entry and exit points as well as the three-dimensional drilling angle. Results: The navigated method was significantly more accurate for all measured parameters at a family-wise significance level of α = 0.05. The median absolute deviation for the entry point was 1.6 mm with navigation versus 3.0 mm with the conventional method (p < 0.001). Similarly, the exit point deviation was 1.8 mm with navigation versus 6.7 mm conventionally (p < 0.001). The drilling angle deviation also showed significant improvement with navigation, at 2.6° compared to 8.9° conventionally (p < 0.001). However, the navigated method took longer, with a median drilling time of 100.0 s compared to 55.0 s for the conventional method (p < 0.001). The navigated method provided consistent and superior results regardless of a participant’s surgical experience. Conclusions: Navigated techniques for K-wire positioning in RSA demonstrate enhanced accuracy in a 3D-printed model, effectively executing a precise, patient-specific preoperative plan. This could be a direct contribution to personalized medicine, ensuring the final implant alignment is tailored to the individual’s anatomy. Furthermore, intraoperative navigation may contribute to a flatter learning curve, thereby increasing accessibility for surgeons with varying levels of experience. Although navigation introduces additional costs and longer initial procedure times, these drawbacks could be offset by improved technical outcomes and a reduced risk of complications. Future studies, including randomized clinical trials and cost-effectiveness analyses, should seek to validate these results in clinical settings with longer follow-up periods and larger patient cohorts to define long-term value and utility of navigation systems in reverse shoulder arthroplasty. Full article

Background/Objectives: Horizontal alveolar ridge deficiency is a common clinical challenge in dental implant placement. The osseodensification (OD) technique has been proposed as a minimally invasive alternative to conventional osteotomy. This study aimed to compare the outcomes of OD and conventionally performed ridge-split procedures in terms of implant stability and horizontal bone gain. Methods: In this retrospective study, 65 patients (a total of 268 implants) who underwent simultaneous implant placement with ridge-split procedures were evaluated. Cases were divided into two groups: OD burs (n = 133 implants) and the conventional Esset kit (n = 135 implants). Ridge width was measured at coronal and apical levels using cone-beam computed tomography (CBCT) preoperatively and four months postoperatively. Implant stability was assessed at the time of placement (primary stability) and at four months (secondary stability) using resonance frequency analysis (RFA). Results: Both techniques achieved comparable horizontal bone gain (1.1–1.6 mm; p > 0.05). In the maxilla, the OD group demonstrated a tendency toward higher primary and secondary stability values (p < 0.01). A similar trend was observed for secondary stability in the mandibular posterior region (p < 0.01). The mean Implant Stability Quotient (ISQ) values in the OD group generally exceeded the threshold of 65, considered sufficient for prosthetic loading. Conclusions: The findings suggest that the OD technique may have a favorable effect on implant stability, particularly in regions with low-to-moderate bone density, while providing comparable horizontal bone gain to the conventional method. These results indicate that OD could serve as a potentially useful alternative in the management of horizontal ridge deficiencies; however, its long-term efficacy should be further evaluated in larger, prospective clinical studies. Full article

Background: The morphology of implant threads plays a crucial role in achieving primary stability, which is essential for successful osseointegration and immediate loading of dental implants. This study aimed to evaluate how different implant thread pitches and an under-preparation drilling technique impact primary stability using an in vitro model. Methods: The study was conducted on low-density polyurethane bone models with and without cortical layers. The following three different implant thread profiles were tested: CYROTH 0.40 (0.40 mm), CYROTH 0.45 (0.45 mm), and CYROTH T (0.35 mm). Two different drilling procedures were utilized, with diameters of 3.4 mm and 3.7 mm, at a low rotational speed of 30 rpm. Primary stability was assessed by measuring insertion torque (IT), removal torque (RT), and resonance frequency analysis (RFA). Results: The low rotational speed of 30 rpm was found to be effective for achieving favorable fixation parameters in all scenarios. The 0.45 mm thread consistently exhibited higher implant stability quotient (ISQ) values (from two to six points higher) compared to the 0.40 mm and standard 0.35 mm threads, while also requiring lower IT. The highest ISQ values were recorded in the 20 pounds per cubic foot (PCF) block with a cortical layer using the 0.45 mm thread and a 3.4 mm drill. The under-preparation using the 3.4 mm drill resulted in higher IT and RT values than the 3.7 mm drill. Conclusions: This study demonstrated that implant thread pitch and drilling technique are critical factors influencing primary stability. Utilizing a wider thread pitch (0.45 mm) along with an under-preparation drilling protocol can significantly improve implant stability, even in low-density bone, without the need for excessive IT. These findings suggest that selecting the appropriate implant macrogeometry and surgical technique can optimize the primary stability of dental implants. Full article

Bone drilling is a widely encountered process in orthopedic surgeries and keyhole neuro surgeries. We are developing a sensor-integrated smart end-effector for drilling for robotic surgical applications. In manual surgeries, surgeons assess tool wear based on experience and force perception. In this work, we propose a machine-learning (ML)-based tool condition monitoring system based on multi-sensor data to preempt excessive tool wear during drilling in robotic surgery. Real-time data is acquired from the six-component force sensor of a collaborative arm along with the data from the temperature and multi-axis vibration sensor mounted on the bone specimen being drilled upon. Raw data from the sensors may have noises and outliers. Signal processing in the time- and frequency-domain are used for denoising as well as to obtain additional features to be derived from the raw sensory data. This paper addresses the challenging problem of identification of the most suitable ML algorithm and the most suitable features to be used as inputs to the algorithm. While dozens of features and innumerable machine learning and deep learning models are available, this paper addresses the problem of selecting the most relevant features, the most relevant AI models, and the optimal hyperparameters to be used in the AI model to provide accurate prediction on the tool condition. A unique framework is proposed for classifying tool wear that combines machine learning-based modeling with multi-sensor data. From the raw sensory data that contains only a handful of features, a number of additional features are derived using frequency-domain techniques and statistical measures. Using feature engineering, we arrived at a total of 60 features from time-domain, frequency-domain, and interaction-based metrics. Such additional features help in improving its predictive capabilities but make the training and prediction complicated and time-consuming. Using a sequence of techniques such as variance thresholding, correlation filtering, ANOVA F-test, and SHAP analysis, the number of features was reduced from 60 to the 4 features that will be most effective in real-time tool condition prediction. In contrast to previous studies that only examine a small number of machine learning models, our approach systematically evaluates a wide range of machine learning and deep learning architectures. The performances of 47 classical ML models and 6 deep learning (DL) architectures were analyzed using the set of the four features identified as most suitable. The Extra Trees Classifier (an ML model) and the one-dimensional Convolutional Neural Network (1D CNN) exhibited the best prediction accuracy among the models studied. Using real-time data, these models monitored the drilling tool condition in real-time to classify the tool wear into three categories of slight, moderate, and severe. Full article

Suture anchors are widely used for tendon and ligament repair, but their fixation strength is compromised in osteoporotic bone and limited bone volume such as the coracoid process. Existing designs are prone to penetration and insufficient cortical engagement under such conditions. In this study, we developed a novel short expandable-wing (SEW) suture anchor (Ti6Al4V) designed to enhance pull-out resistance through a deployable wing mechanism that locks directly against the cortical bone. Finite element analysis based on CT-derived bone material properties demonstrated reduced intra-bone displacement and improved load transfer with the SEW compared to conventional anchors. Mechanical testing using matched artificial bone surrogates (N = 3 per group) demonstrated significantly higher static pull-out strength in both normal (581 N) and osteoporotic bone (377 N) relative to controls (p < 0.05). Although the sample size was limited, results were consistent and statistically significant. After cyclic loading, SEW anchor fixation strength increased by 25–56%. In a 3D-printed anatomical coracoclavicular ligament reconstruction model, the SEW anchor provided nearly double the fixation strength of the hook plate, underscoring its superior stability under high-demand clinical conditions. This straightforward implantation protocol—requiring only a 5 mm drill hole without tapping, followed by direct insertion and knob-driven wing deployment—facilitates seamless integration into existing surgical workflows. Overall, the SEW anchor addresses key limitations of existing anchor designs in small bone volume and osteoporotic environments, demonstrating strong potential for clinical translation. Full article

Osseodensification (OD) compacts trabecular bone during implant site preparation rather than removing it, potentially enhancing primary stability versus conventional drilling. This review critically appraised clinical and preclinical evidence for OD’s biological and biomechanical efficacy in implant dentistry. We conducted electronic searches in seven databases (PubMed, Scopus, Web of Science, ScienceDirect, SciELO, LILACS, DOAJ) for the period January 2014 to March 2024. Studies comparing osseodensification with conventional drilling in clinical and large-animal models were included. Primary outcomes were insertion torque, implant stability quotient (ISQ), bone-to-implant contact (BIC), bone area fraction occupancy (BAFO), and complications. Of 75 retrieved records, 38 studies (27 clinical, 11 preclinical) provided analysable data. Based on descriptive averages from the narrative synthesis, osseodensification increased mean insertion torque by around 45% (range 32–59%) and initial ISQ by 3–10 units compared with conventional drilling. These gains permitted immediate loading in 78% of cases and shortened operating time (mean reduction 15–20 min). Animal studies demonstrated 12–28% higher BIC and increased peri-implant bone density at 4–12 weeks. No serious adverse events were recorded. Postoperative morbidity was similar between techniques. The collated evidence indicates that osseodensification significantly improves primary stability and may accelerate healing protocols, particularly in low-density (Misch D3–D4) bone. However, the predominance of short-term data and heterogeneity in surgical parameters limit definitive conclusions. Long-term randomised controlled trials with standardised protocols are needed before universal clinical recommendations can be established. Full article

Osseodensification (OD) has emerged as a favorable osteotomy preparation technique that preserves and compacts autogenous bone along the osteotomy walls during site preparation, enhancing primary stability and implant osseointegration. While OD has demonstrated promising results in low-density trabecular bone, especially when used in conjunction with acid-etched (AE) implant surfaces, its efficacy in high-density cortical bone remains unclear—particularly in the context of varying implant surface characteristics. In this study, Grade V titanium alloy implants (Ti-6Al-4V, 4 mm × 10 mm) with deep threads, designated bone chambers and either as-machined (Mach) or AE surfaces were placed in 3.8 mm diameter osteotomies in the submandibular region of 16 adult sheep using either OD or conventional (Reg) drilling protocols. Insertion torque values (N·cm) were measured at the time of implant placement to evaluate primary stability. Mandibles were harvested at 3-, 6-, 12-, or 24-weeks post-implantation (n = 4 sheep/time point), and histologic sections were analyzed to quantify bone-to-implant contact (BIC) and bone area fractional occupancy (BAFO). Qualitative histological analysis confirmed successful osseointegration among all groups at each of the healing time points. No statistically significant differences were observed between OD and conventional drilling techniques in insertion torque (p > 0.628), BIC (p > 0.135), or BAFO (p > 0.060) values, regardless of implant surface type or healing interval. The findings indicate that neither drilling technique nor implant surface treatment significantly influences osseointegration in high density cortical bone. Furthermore, as the osteotomy was not considerably undersized, the use of OD instrumentation showed no signs of necrosis, inflammation, microfractures, or impaired osseointegration in dense cortical bone. Both OD and Reg techniques appear to be suitable for implant placement in dense bone, allowing flexibility based on surgeon preference and clinical circumstances. Full article

The French Bulldog is a breed predisposed to lateral humeral intercondylar fractures. A transcondylar lag screw combined with an epicondylar pin is most commonly used for their repair. However, improper screw and pin placement is common. This study used a 3D-printed plastic bone model, designed from a 5-year-old 19.5 kg French Bulldog’s humerus. Then, a 3D-printed drill guide was designed specifically for a lateral humeral condylar fracture. The bone models were divided into two groups: the first group included the use of the 3D-printed drill guide during the screw and pin placement, and the second group did not. After implantation, we compared the angle deviation of the transcondylar screw and the epicondylar pin, as well as the exit point translation of the transcondylar screw. The results showed differences between the two groups. The first group exhibited a lower angle deviation than the second group. Additionally, the exit point translation of the transcondylar screw was reduced in the drill guide group. The use of a custom-designed 3D-printed drill guide significantly improved the accuracy of the transcondylar screw and epicondylar pin placement. This advancement could reduce the incidence of postoperative complications. Full article

Background. The use of zygomatic implants (ZIs) provides a highly predictable treatment option for rehabilitation in patients with severe atrophic maxillae. However, these long implants can potentially cause a number of more serious complications than those seen with conventional dental implants. The aim of this study is to report a case of peri-zygomatic cutaneous fistula following placement of monolateral double zygomatic implants and to analyse the available literature on this complication. Methods. The 55-year-old patient was treated with placement of 3 ZIs, two on the left side. Left periorbital swelling with pain appeared 10 days after surgery with progressive worsening of symptoms. After antibiotic treatment, she developed a left cutaneous fistula with purulent discharge. CT showed two ZIs on the left side with the apical portions in close contact with a 1 cm-wide portion of resorbed zygomatic external cortex and a layer of granulation tissue. Results: Due to the limited amount of bone involved by the fixation tip, the left ZIs were removed and the skin fistula repaired. The patient healed without complications but required prosthesis replacement. Conclusions. After conducting a literature review, peri-zygomatic fistulas seem to be more common in patients with two ZIs placed on the same zygoma. In this case, the amount of available zygomatic bone is relatively limited; the bone drill holes can often be too close together and cause overheating, leading to inter-implant bone resorption and infection, with further orbito-zygomatic fistula development. The authors identified the lack of distance between ZI fixtures as one of the main causes of extraoral ZI infection. Full article

Background: Primary implant stability is a critical factor for successful osseointegration and long-term implant success. This study investigates the impact of drilling protocol modifications on primary stability, considering different bone qualities and implant macro-designs, lengths, and diameters. Material and Methods: Three implant designs—two parallel-walled and one tapered—were tested with diameters ranging from 3.4 to 5.2 mm and lengths from 7.5 to 14.5 mm. Implants were placed in polyurethane foam blocks simulating different bone densities (10, 15, 25, and 35 PCF). A standard drilling protocol was used in all groups, with modifications based on bone quality: overpreparation in dense bone and underpreparation in softer bone. Primary stability was evaluated using insertion torque (IT). The optimal IT range was defined as 25–50 Ncm, based on clinical guidelines for immediate loading. The influence of drilling protocol adaptations on stability parameters was assessed. Results: Insertion torque was primarily influenced by bone density and implant diameter, with implant length playing a minor role. In dense bone (D1, D2), underpreparation improved torque values, especially in smaller implants, while overpreparation reduced them. The highest torques occurred with 5.2 mm implants, sometimes exceeding 80 Ncm. Standard protocols did not consistently achieve optimal torque across implant types. In soft bone (D3), underpreparation—particularly with tapered implants—was modestly beneficial. In very soft bone (D4), none of the protocols reliably reached the desired torque range. Conclusions: Adapting drilling protocols to bone density improves insertion torque, especially with wider implants and in denser bone. Underpreparation is generally more effective than overpreparation. However, in very soft bone, neither implant geometry nor drilling adaptations reliably achieve optimal primary stability, highlighting the need for additional strategies. Full article

Osteosarcoma is one of the most common primary bone malignancies, typically occurring around the knee. However, the forearm is a rare site, with tumors in the proximal ulna being extremely uncommon. Primary sarcoma in this location presents a surgical challenge due to the complex anatomy and limited reconstructive options. We report a rare case of a 19-year-old female with non-metastatic, high-grade giant cell-rich osteosarcoma involving the right proximal ulna. To our knowledge, this is only the second reported adult case of this histological subtype in this location. The patient was treated at a specialized oncology center with neoadjuvant and adjuvant chemotherapy, along with wide intra-articular resection for local tumor control. Reconstruction was achieved using a novel, customized 3D-printed articulating cement spacer mold with plate osteosynthesis. Artificial elbow ligamentous reconstruction was performed using FiberTape and FiberWire sutures passed through drill holes, and the triceps tendon was reattached to the cement mold using an endobutton. This cost-effective and personalized surgical approach allowed successful joint reconstruction while maintaining elbow stability and function. Our case highlights a feasible reconstructive option for rare and anatomically challenging osteosarcoma presentations, contributing to the limited literature on proximal ulna giant cell-rich osteosarcoma. Full article

Partially guided implant surgery has emerged as a technique that enhances the precision of implant placement while maintaining surgical flexibility. This in vitro experimental study evaluated the influence of the milling cutter drill on the angular and linear deviations of implant placement in synthetic polyurethane bone models using a partially guided surgical protocol. Additionally, the effects of bone density and implant macrogeometry were assessed. A total of 120 Straumann^® implants (BL, BLT, and BLX) were placed in polyurethane blocks simulating four bone densities (D1–D4). Implant positions were virtually planned with coDiagnostiX^® (version 10.9) software and executed with or without the use of the milling cutter drill. Deviations between planned and final implant positions were measured at the neck and apex using the software’s “Treatment Evaluation” tool. The use of the milling cutter drill significantly reduced angular deviation (p = 0.007), while linear deviations showed no statistically significant differences. Bone density and implant macrogeometry did not significantly affect angular deviation but influenced linear and 3D deviations. Given that angular deviation may compromise prosthetic fit and biomechanical function, the observed reduction is of potential clinical relevance. These findings indicate that the milling cutter drill enhances angular accuracy in partially guided implant surgery and may improve outcomes in anatomically challenging cases. However, the results should be interpreted within the limitations of this in vitro model, including the absence of soft tissue simulation, intraoral constraints, and inter-operator variability. Full article

Some additives currently used to enhance drilling mud’s rheological qualities have a substantial economic impact on society. Carboxymethyl cellulose (CMC) and calcium carbonate (CaCO₃) are currently imported. Food crops have influences on food security; hence, this research explored the potential of utilizing cow bone powder (CBP), a bio-waste product and a renewable resource, as an environmentally friendly fluid-loss additive for drilling applications, in comparison with CaCO₃. Both samples (CBP and CaCO₃) were evaluated to determine the most efficient powder sizes (coarse, medium, and fine powder), concentrations (5–15 g), and aging conditions (before or after aging) that would offer improved rheological and fluid-loss control. The results obtained showed that CBP had a significant impact on mud rheology when compared to CaCO₃. Decreasing the particle size (coarse to fine particles) and increasing the concentration from 5 to 15 g positively impacted mud rheology. Among all the conditions analyzed, fine-particle CBP with a 15 g concentration produced the best characteristics, including in the apparent viscosity (37 cP), plastic viscosity (29 cP), and yield point (25.5 lb/100 ft²), and a gel strength of 16 lb/100 ft² (10 s) and 28 lb/100 ft² (10 min). The filtration control ability of CaCO₃ was observed to be better than that of the coarse and medium CBP particle sizes; however, fine-particle-size CBP demonstrated a 6.1% and 34.6% fluid-loss reduction at 10 g and 15 g concentrations when compared to respective amounts of CaCO₃. The thermal behavior of the Mud Samples demonstrated that it positively impacted rheology before aging. In contrast, after aging, it exhibited a negative effect where samples grew more viscous and exceeded the API standard range for mud properties. Therefore, CBP’s excellent rheological and fluid-loss control ability makes it a potential, sustainable, and economically viable alternative to conventional materials. This superior performance enhances the thinning properties of drilling muds in stationary and circulating conditions. Full article

Background/Objectives: Guided implant surgery relies on the use of surgical templates to direct osteotomy drills, but guide design may influence irrigation efficiency, hence bone overheating, a critical factor in preventing thermal necrosis. This ex vivo study compared temperature changes when drilling using two guide designs: a closed-frame (occlusive structure) and an open-frame (non-occlusive design), evaluating their clinical relevance in mitigating overheating. Methods: Sixteen pig ribs were scanned, and implant osteotomies were planned via a guided surgery software. Two 3D-printed resin templates, one with a closed-frame design and one with an open-frame design, were tested (8 ribs per group, 24 implants per group). Drilling was performed sequentially (diameter of 1.9 mm, 3.25 mm, and 4.1 mm) at 800 rpm, while bone temperatures were recorded at depths of 3 mm and 10 mm using K-type thermo§s. Results: Significantly higher temperature rises were observed with the closed-frame guide. Drilling depth had also a significant influence, with higher temperatures at 3 mm than 10 mm (p < 0.001), suggesting that cortical bone density may amplify frictional heat. No significant effect of drill diameter was detected. Conclusions: Within the limitations of this ex vivo model, the open-frame design kept the maximal temperature rise about 0.67 °C lower than the closed-frame guide (1.22 °C vs. 0.55 °C), i.e., a 2.2-fold relative reduction was observed during the most demanding drilling step. This suggests a more efficient cooling capacity, especially in dense cortical bone, which offers a potential benefit for minimizing thermal risk in guided implant procedures. Full article