Search Results (189)

The aim of this study was to evaluate and compare the stress concentration of short dental implants supporting different conical abutments using 3D finite element analysis (3D-FEA). A tridimensional model of single-unit short dental implants (5.2 mm × 5 mm) was designed using the computer-aided design (CAD) software based on the manufacturer’s stereolithography. The short implants were positioned in a bone model to support titanium or ceramic-reinforced PEEK conical abutments considering different bone levels (supra-crestal, crestal or sub-crestal). With the aid of a computer-aided engineering (CAE) software, the finite element model was created and an axial load of 500 N was applied. Observing the mechanical response of the implant, abutment and screw, both evaluated materials resulted in homogeneous stress and could be indicated for implant-supported restorations with short fixtures. However, aiming to decrease the strain in the bone tissue, placing the implant in the sub-crestal position is a preferable option; while the supra-crestal placement decreases the stress at the screw and implant. Full article

This study compares the effect of different handpieces (turbine, high-speed electric handpiece and piezoelectric device) on surface roughness of enamel and dentin when using diamond-coated working tips and burs of the same grit size. The experiment was conducted on 15 extracted first molars from patients aged 45 to 60 years. The occlusal portion was removed using a diamond-coated water wheel and then refined with a 120–130 μm grit bur in order to obtain a flat surface with an adequate exposition of the dentin core. Each surface was divided into three portions and every portion was finished with one of the three tested instruments. The rotary burs and piezoelectric tips had the same grit size (60 μm), and the load on handpiece during preparation never exceeded 150 g. Roughness parameters (Ra, Rsk, Rku) were recorded with a profilometer, and a SEM analysis of treated surfaces and working tips was conducted. Ra and Rsk differed significantly between enamel and dentin only after using turbine (p = 0.004 and p = 0.007, respectively). No significant differences were observed in Ra, Rsk and Rku between enamel and dentin when using a high-speed electric handpiece or piezoelectric device. The turbine produced higher Ra and Rsk values on dentin than the other devices, while no significant differences were found between piezoelectric handpiece and high-speed electric contra-angle on both substrates. Summarizing, the findings of the present study demonstrated that turbine generated rougher surfaces on dentin compared to the other handpieces. Moreover, the turbine produced more asymmetrical surface profiles on both enamel and dentin. However, it should be considered that these differences in roughness (Ra) were within the range of 0.25–0.30 μm: it is still unclear if these variations, although statistically significant, will influence final clinical outcomes. Full article

Background: An effective way to objectively assess intraoperative tissue damage in total hip arthroplasty (THA) is to determine and compare postoperative serum biomarkers (laboratory parameters) such as creatine kinase (CK), C-reactive protein (CRP), and hemoglobin (Hb). This meta-analysis aims to compare the intraoperative tissue damage in THA through minimally invasive (MI) and conventional approaches (CAs) using postoperative serum biomarkers. Methods: We searched databases for randomized controlled trials (RCTs) comparing MI THA and CA THA. We calculated mean differences (MDs) with 95% confidence intervals (CIs) for continuous outcomes, using the Hartung–Knapp–Sidik–Jonkman method and a common effect/random effects model. Results: A total of 13 RCTs, involving 1186 THA patients, were included in our meta-analysis. In two out of eleven examined outcome parameters, MI THA showed better results than CA THA. In nine out of eleven examined outcome parameters, MI THA showed no significant difference compared to CA THA. MI THA had a 16 mg/L lower CRP value 3 days postoperatively than CA THA (I² = 66%, p = 0.03, MD = −15.65, 95% CI −30.10 to −1.21). MI THA had a 3 mg/L lower CRP value 4 days postoperatively than CA THA (I² = 0%, p = 0.98, MD = −3.00, 95% CI −3.27 to −2.74). Conclusions: Overall, there was no significant difference between MI THA and CA THA in terms of postoperative serum biomarkers, with a slight advantage of MI THA in CRP values. These results do not provide sufficient evidence to recommend changing the surgical approach from CA THA to MI THA. Level of evidence I: a systematic review of all relevant randomized controlled trials. Full article

The natural distribution of stress in the femur is altered when total hip arthroplasty (THA) is performed. In fact, when a stem is inserted inside the femur, there is a variation in stress due to the difference in rigidity between the material with which the stem is made and the femur. This generates the phenomenon of stress shielding. The aim of this study is to design an optimized prosthesis that guarantees an excellent rotational stability and a reduced stress shielding. Methods: Through the finite element method (FEM), the mechanical behavior of the stem subjected to the loads described by ISO 7206-4:2010 is studied. Results: Through topological optimization, there is a reduction in stress shielding in the proximal zone of 31.46%. The addition of ridges on the dorsal side of the stem also improves rotational stability by 27.82%. Conclusions: The decrease in stiffness that is recorded with the optimized stem guarantees a greater distribution of stress on the bone. The presence of dorsal ridges also favors the corticalization of the bone as it loads the bone near the dorsal, ensuring further stability. The perforated prosthesis presented in this study shows an increase in primary stability and an improvement in rotational stability as there is also a bone regrowth inside the prosthesis. Full article

Digital dentistry has gained significant attention in recent years due to its potential to improve the accuracy of implant placement and prosthesis fabrication. However, the literature on its effectiveness remains controversial, and a systematic review and meta-analysis are necessary to evaluate the available evidence. A comprehensive search was conducted across multiple online databases using MeSH keywords and Boolean operators. Data extraction was performed, and a bias assessment was conducted based on modified CONSORT guidelines. The pooled odds ratios (OR) and risk ratios (RR) and corresponding 95% confidence intervals (CI) were then calculated. Five studies met the inclusion criteria. The overall analysis showed no statistically significant difference in the accuracy of implant placement and prosthesis fabrication between digital and conventional techniques (OR: 0.95, 95% CI: 0.73 to 1.23 and RR: 0.95, 95% CI: 0.73 to 1.23). Subgroup analysis based on individual studies did not demonstrate consistent results. This review suggests that digital techniques do not significantly impact the accuracy of implant placement and prosthesis fabrication compared to conventional techniques in an in vitro setting. However, the overall evidence is limited by the small number of studies and the heterogeneity observed. Future well-designed studies, including randomized controlled trials and clinical studies, are needed to provide more robust evidence on the effectiveness of digital dentistry in clinical practice. Full article

Prosthetics and orthotics research, studies, and technologies have been evolving through the years. According to World Health Organization (WHO) data, it is estimated that, globally, 35–40 million people require prosthetics and orthotics usage in daily life. Prosthetics and orthotics demand is increasing due to certain factors. One of the factors is vascular-related disease, which leads to amputation. Prosthetic usage can increase an amputee’s quality of life. Therefore, studies of the ergonomic design of prosthetics are important. The ergonomic factor in design delivers prosthetic products that are comfortable for daily use. One way to incorporate the ergonomic design of prosthetics is by studying the human walking gait. This paper presents a multiclassification of human walking gait based on electromyography (EMG) signals using a machine learning method. An EMG sensor was attached to the bicep femoris longus and gastrocnemius lateral head to acquire the EMG signal. The experiment was conducted by volunteers during normal walking activity at various speeds and the movements were segmented as initial contact, which was labeled as initial gait; loading response to the terminal stance, which was labeled as mid-gait; and pre-swing to terminal swing, which was labeled as final gait. The EMG signal was then characterized using an artificial neural network (ANN) and compared to six training accuracy methods, i.e., the Levenberg–Marquardt backpropagation training algorithm, quasi-Newton training method, Bayesian regulation backpropagation training method, gradient descent backpropagation, gradient descent with adaptive learning rate backpropagation, and one-step secant backpropagation. The machine learning study performed well in the classification of three classes of human walking gait with an overall accuracy (training, testing, and validation) of 96% for Levenberg–Marquardt backpropagation. The gait data will be used to explore the design of lower limb prosthetics in future research. Full article

The aim of this systematic scoping review was to provide scientific evidence on the efficacy and methods of application of hyaluronic acid (HA) in the coverage of gingival recessions in terms of recession depth (RD) reduction, clinical attachment level (CAL) gain and probing depth (PD). An electronic search of the literature on the main databases was conducted. Initially, 405 articles were identified. Finally, four studies were included after the review process. It was not possible to perform a meta-analysis of the articles selected because of the differences among the surgical treatments and commercial formulations and compositions of HA. Both randomized controlled trials in this research examined type 1 gingival recessions treated with a coronally advanced flap. In the selected case series, recessions were treated with either a modified coronally advanced tunnel or laterally closed tunnel combined with a subepithelial connective tissue graft and HA. No significant variation was found in terms of PD. Modifications of CAL are connected to variations of RD; however, RD reduction is similar to the control group. HA seems to improve the clinical outcomes of gingival recession coverage in the short term, but the magnitude is limited. Formulations, surgical techniques and application methods are heterogeneous. Full article

Total knee arthroplasty (TKA) is a popular treatment for end-stage knee osteoarthritis. Advances in understanding knee biomechanics have led to the development of medial pivot (MP) prostheses, which aim to replicate natural knee kinematics. While short- and mid-term studies have shown favorable outcomes for MP-TKA, long-term follow-up studies are limited. This systematic review aims to analyze the available evidence on long-term outcomes of MP-TKA, including survivorship, complications, and patient-reported outcome measures (PROMs). A comprehensive search was conducted in PubMed, Embase, and Cochrane Database of Systematic Reviews for English language studies reporting long-term outcomes of primary MP-TKA. Nine studies with an average follow-up of 12.4 years were included. Data on survivorship, complications, and PROMs were collected and analyzed. The overall survivorship of MP-TKA was 98.2% at an average follow-up of 12.4 years. Aseptic loosening and periprosthetic joint infection (PJI) were the most common reasons for revision, with a revision rate of 0.4% for each. The overall complication rate was 6.6%, with secondary anterior knee pain and PJI being the most frequent complications. The reoperation rate was 3.1%, primarily due to PJI and knee instability. PROMs significantly improved postoperatively. MP-TKA demonstrates favorable long-term outcomes with high survivorship, low complication rates, and enhanced PROMs. The procedure provides reliable management for end-stage osteoarthritis, offering patients improved knee function and pain relief. Further research with standardized reporting and larger sample sizes is needed to validate and compare these findings to other implant designs. Full article

Background: Dental implants have become the standard for replacing missing teeth. However, patients’ demands for shorter treatment times and the desire for aesthetics in their results can complicate the rehabilitation process, particularly when poor-quality bone is involved. In order to address these challenges, new methods of treating implant surfaces have been introduced. These methods aim to make the implants superhydrophilic and bioactive, enhancing their functionality and interactions with the surrounding tissues. Aim: The aim of the study was to retrospectively examine the efficacy of a superhydrophilic and bioactive implant for treatment of the edentulous maxillary anterior area. The study also aimed to evaluate whether this improved implant surface, by enhancing the osseointegration processes, could serve as a factor in speeding up the loading protocols. Materials and Methods: For this retrospective study, a total of 13 implants were included: 6 delayed restored implants and 7 immediately loaded implants placed in the anterior maxillary area. Clinical, radiographic, and esthetic outcomes were assessed. Baseline measurements of the insertion torque value (ITV) and stability implant quotient (ISQ) were recorded for all implants. In the early-loaded group, these measurements were also taken 30 days (t30) and 45 days (t45) after the placement of the implant to monitor their changes over time. Marginal bone loss (MBL) was calculated according to the changes in marginal bone level on intraoral X-rays taken at two different time points: at baseline and one year after loading. To evaluate the esthetic results, the pink esthetic score (PES) and the white esthetic score (WES) were assessed. For this evaluation, intraoral photographs were taken one year after implant loading. Results: A total of 7 implants were immediately restored, with a mean ITV of 32.29 ± 9.01 Ncm and a mean ISQ of 72.71 ± 2.81. These implants were placed in a bone environment with a mean density of 410.00 ± 194.42 HU. On the other hand, 6 implants with delayed loading had a mean ITV of 28.50 ± 3.27 Ncm, an ISQ of 67.92 ± 8.43, and a mean bone density of 607.50 ± 140.83 HU. The mean PES and WES after 1 year were, respectively, 8.71 ± 1.89 and 8.57 ± 0.79 for immediate and 8.33 ± 1.36 and 9.17 ± 1.33 for delayed-loaded implants. At 12 months after loading, the immediately loaded group had a MBL of 0.29 ± 0.29 mm, while the delayed-loaded group had a MBL of 0.33 ± 0.25. No statistically significant differences between the two treatment groups were found for any of the evaluated outcomes. Conclusions: Despite the limitations of this study, the obtained results may support the use of a superhydrophilic and bioactive implant surface for implant-prosthetic rehabilitation in critical loading protocols with satisfactory esthetic results. Full article

Background: Training is required to achieve proficiency in airway management. Simulators are of utmost importance not only for the purpose of training novices, but also for evaluating newer airway devices and techniques. Growing evidence supports inadequate anatomic airway reproduction in adult and pediatric manikins. Methods: We conducted an observational study comparing 17 radiological anatomic airway measurements obtained via the computed tomography of three commercially available manikins with the same measurements obtained from a population of newborns/infant (range: 0–3 months) undergoing magnetic resonance imaging for diagnostic purposes. According to the reference (mean and standard deviation (SD) of the pediatric population), each manikin measurement was defined as adequate, partially adequate or inadequate (difference between means: ≤±1, 1.0–1.96 or >1.96 SD, respectively). The primary outcome was the number of measurements with an adequate reproduction of airways. Results: We included 27 pediatric patients (21 ± 19 days, 48% males, 46.6 ± 3.5 cm, 2.7 ± 0.5 Kg and 12.6 ± 2.9 kg/m²). All manikins had n = 11/17 measurements with inadequate airway anatomic reproduction. The three measurements with more adequate reproduction were the height of the soft palate, retropalatal airspace volume and tongue volume (adequate in two manikins, and partially adequate in the remaining one). Conclusions: In three manikins commonly used for training in pediatric airways, static dimensions do not seem anatomically correct in relation to those of pediatric patients. Such inaccuracies may introduce biases in airway device development as well as in training. Full article

The objective of this study was to meticulously examine the diverse vocal rehabilitation techniques that are employed following total laryngectomy, with emphasis on their implications on patients’ quality of life and on the determinants influencing the selection of one technique over another. We embarked on a comprehensive literature review, which concentrated on three primary rehabilitation approaches: tracheoesophageal puncture (TEP) accompanied by a vocal prosthesis, esophageal speech acquisition, and electrolarynx utilization. The outcomes assessed included quality of life, functional performance, communication effectiveness, patient satisfaction, and factors governing the choice of technique, such as patient demographics, disease stage, and treatment history. Our findings demonstrated that TEP with vocal prosthesis yielded the most favorable overall quality of life and patient satisfaction. Individuals who underwent TEP exhibited superior speech intelligibility, voice quality, and communication ease compared with those who employed esophageal speech acquisition or electrolarynx utilization. While esophageal speech learning exhibited inferior speech quality and functional performance, it offered cost-effectiveness and diminished maintenance advantages. Electrolarynx utilization emerged as the least preferred approach due to suboptimal speech intelligibility and voice quality. The determinants influencing the choice of vocal rehabilitation technique included patient age, sex, disease stage, and previous treatment history. Patient preferences also substantially contributed to the selection of a specific technique. It is essential for clinicians to consider individual factors and patient inclinations when deliberating on an appropriate vocal rehabilitation method following total laryngectomy. Our investigation underscores the significance of collaborative decision making between clinicians and patients to pinpoint the most fitting rehabilitation technique. Future research endeavors should be directed towards enhancing existing approaches, devising innovative methods, and probing long-term outcomes and cost-effectiveness to optimize patient care in the aftermath of total laryngectomy. Full article

People with lower limb amputations struggle through difficulties during locomotion in their daily activities. People with transtibial amputations take support from prosthetic legs for systematic movement. During motion, they experience some mobility issues while using general prosthetic limbs regarding gait pattern. The design of a prosthetic-controlled lower limb with gait synchronization for physically disabled persons is the main goal of the present research work, which can provide an improved walking experience. The design and performance analysis of prosthetic lower limbs for people with transtibial amputations is performed in the present paper. The designed rehabilitation system shows synchronization between the normal and the prosthetic limbs achieved with gait coordination. The dynamics of the lower extremities in different postural activities are used for design purpose utilizing Euler–Lagrange motion theory. The artificial motion of the knee and the ankle joints function through the angular movement of the servo motors according to the movements of the rotary encoders placed on the sound limb joints. The range of motion of both the sound and prosthetic limbs are compared for different steps during a gait cycle. The prosthetic electronic system design of the artificial lower limb is able to show the gait style of human being with body kinesics. The nonlinear domain stability analysis of the designed prosthetic limb is presented through the Lyapunov method. A PIDF2 controller tuning process is implemented for the designed limb’s performance improvement. The designed prosthetic system is beneficial for people with unilateral transtibial amputations with a great societal impact. Full article

Vascular-free flaps are the most frequently employed method in cases of jaws reconstruction after large tumor removal. This therapeutic choice is due to its intrinsic blood supply, which speeds up recovery and enables healing apart from the injured recipient site. This method is most commonly used in secondary reconstructions brought on by radiation, infection, or prior surgical intervention. In fact, with the help of 3d technology, guides can be designed to perform the grafting very smoothly. The purpose of this review with meta-analysis is to compare the two methods: the one using 3d and the freehand one. Methods: In accordance with the entered keywords, a literature search was conducted on PubMed, Lilacs, and Web of Science. Articles published between 2000 and 4 January 2023 were taken into consideration. Using the Boolean connective AND, the terms “jaw reconstruction”, “cad-cam”, and “cancer” have been joined. Results: After searching the three search motors, 148 articles were selected, and only 7 were chosen for this review. Conclusions: The pre-operative morphological position looks to be accurately restored using the CAD/CAM reconstructive methodology. Reconstruction using CAD-CAM and 3d technology allows for greater accuracy, less operative time, and improved aesthetics. Full article

The prevalence of individuals with flat feet and high arches is very high (between 15% to 37%), which can often lead to other orthopedic complications. Three-dimensional-printed insoles are being studied and validated for their effects in correcting these highly prevalent foot disorders. Highly customizable parameters while printing the insole allows for precise correction of foot biomechanics. In this study, 200 patients suffering from various foot-related problems and joint pain were given 3d-printed insoles (designed using plantar pressure systems and clinical practitioner’s assessment) to use in their footwear. Tested activities included standing, walking, running, sports, and gym workout. Customization of insoles included custom density, heel cup, heel rise, medial arch height, and lateral wedge. Based on the patient history, additional podiatry elements were provided for patients with diabetes. Each insole was designed as per the insole profile of the shoe with a comfortable fit. These insoles were found to be effective in alleviating pain for more than 90% of the patients and provided a longer life cycle with effective orthotic correction (for >16 months of daily use). This paper presents the post-use effects (6–18 months) of custom 3D-printed insoles. Full article

Background: Effective debris and smear layer removal affects post-cementation and bond strength. Aim: The aim was to compare the effectiveness of debris and smear layer removal using standard irrigation and activated irrigation with heated EDTA. Moreover, an irrigant activation technique was chosen in the current research, employing the ultrasonic activation of an EDTA solution after being heated directly inside the post space preparation. Materials and Methods: 30 single-rooted human mandibular premolar teeth were used in the current study to test the proposed techniques. First, the teeth were cut to have standardised roots 18 mm in length and prepared endodontically, and then the post space was carried out on all the samples. Then the specimens were randomly distributed into three study groups according to the post space irrigation technique. In detail, the groups were group 1, where a 3D cleaning technique was used; group 2, where the traditional irrigation with EDTA was applied; and group 3, where only saline as an irrigant was used. The third group was considered the control group. Next, the teeth were segmented and analysed via scanning electron microscopy (SEM). The magnification was used to evaluate and score the smear layer and debris. Statistical analysis was undertaken using the classic statistical software package (SPSS, version 28.0; SPSS IBM, Armonk, NY, USA). Then, the data were interpreted with a non-parametric analysis of variance (Kruskal–Wallis ANOVA) among the experiment groups. The significance level was decided as p < 0.05. In addition, statistically significant (p < 0.05) lower mean smear layer and debris scores were found in both the examination groups compared to the control group. Results: group 1 demonstrated better results compared to group 2 in terms of cleaning the dentinal walls. Conclusions: The current research concluded that the EDTA 3D cleaning technique is an effective irrigation technique for clearing debris and smear layers in the post space. Future research, such as on push-out bond strength, should be used to verify this research’s conclusions. Key findings: The use of ultrasonically activated heated EDTA improved the smear layer removal. The use of the 3D cleaning technique resulted in better post space cleaning. Full article